WorldWideScience

Sample records for magnitude

  1. Teleseismic magnitude relations

    Directory of Open Access Journals (Sweden)

    Markus Båth

    2010-02-01

    Full Text Available Using available sets of magnitude determinations, primarily from Uppsala seismological bulletin, various extensions are made of the Zurich magnitude recommendations of 1967. Thus, body-wave magnitude (m and surface-wave magnitudes (M are related to each other for 12 different earthquake regions as well as world-wide. Depth corrections for M are derived for all focal depths. Formulas are developed which permit calculation of M also from vertical component long-period seismographs. Body-wave magnitudes from broad-band and narrow-band short-period seismographs are compared and relations deduced. Applications are made both to underground nuclear explosions and to earthquakes. The possibilities of explosion-earthquake discrimination on the basis of magnitudes are examined, as well as the determination of explosive yield from magnitudes. For earthquakes, relations between magnitudes of main earthquakes and largest aftershocks are investigated. A world-wide station network for more homogeneous magnitude determinations is suggested in order to provide the necessary reference system.

  2. Moment magnitude scale

    Energy Technology Data Exchange (ETDEWEB)

    Hanks, T.C.; Kanamori, H.

    1979-05-10

    The nearly conincident forms of the relations between seismic moment M/sub o/ and the magnitudes M/sub L/, M/sub s/, and M/sub w/ imply a moment magnitude scale M=2/3 log M/sub o/-10.7 which is uniformly valid for 3< or approx. =M/sub L/< or approx. = 7, 5 < or approx. =M/sub s/< or approx. =7 1/2 and M/sub w/> or approx. = 7 1/2.

  3. Right idea, wrong magnitude system.

    Science.gov (United States)

    Lourenco, Stella F; Aulet, Lauren S; Ayzenberg, Vladislav; Cheung, Chi-Ngai; Holmes, Kevin J

    2017-01-01

    Leibovich et al. claim that number representations are non-existent early in life and that the associations between number and continuous magnitudes reside in stimulus confounds. We challenge both claims - positing, instead, that number is represented independently of continuous magnitudes already in infancy, but is nonetheless more deeply connected to other magnitudes through adulthood than acknowledged by the "sense of magnitude" theory.

  4. Moment Magnitude discussion in Austria

    Science.gov (United States)

    Weginger, Stefan; Jia, Yan; Hausmann, Helmut; Lenhardt, Wolfgang

    2017-04-01

    We implemented and tested the Moment Magnitude estimation „dbmw" from the University of Trieste in our Antelope near real-time System. It is used to get a fast Moment Magnitude solutions and Ground Motion Parameter (PGA, PGV, PSA 0.3, PSA 1.0 and PSA 3.0) to calculate Shake and Interactive maps. A Moment Magnitude Catalogue was generated and compared with the Austrian Earthquake Catalogue and all available Magnitude solution of the neighbouring agencies. Relations of Mw to Ml and Ground Motion to Intensity are presented.

  5. Integrated Circuit Stellar Magnitude Simulator

    Science.gov (United States)

    Blackburn, James A.

    1978-01-01

    Describes an electronic circuit which can be used to demonstrate the stellar magnitude scale. Six rectangular light-emitting diodes with independently adjustable duty cycles represent stars of magnitudes 1 through 6. Experimentally verifies the logarithmic response of the eye. (Author/GA)

  6. Scaling relations of moment magnitude, local magnitude, and duration magnitude for earthquakes originated in northeast India

    Science.gov (United States)

    Bora, Dipok K.

    2016-06-01

    In this study, we aim to improve the scaling between the moment magnitude ( M W), local magnitude ( M L), and the duration magnitude ( M D) for 162 earthquakes in Shillong-Mikir plateau and its adjoining region of northeast India by extending the M W estimates to lower magnitude earthquakes using spectral analysis of P-waves from vertical component seismograms. The M W- M L and M W- M D relationships are determined by linear regression analysis. It is found that, M W values can be considered consistent with M L and M D, within 0.1 and 0.2 magnitude units respectively, in 90 % of the cases. The scaling relationships investigated comply well with similar relationships in other regions in the world and in other seismogenic areas in the northeast India region.

  7. EOP Current Magnitude and Direction

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data contain shipboard current magnitudes and directions collected in the Pacific, both pelagic and near shore environments. Data is collected using an RD...

  8. Magnitude conversion to unified moment magnitude using orthogonal regression relation

    Science.gov (United States)

    Das, Ranjit; Wason, H. R.; Sharma, M. L.

    2012-05-01

    Homogenization of earthquake catalog being a pre-requisite for seismic hazard assessment requires region based magnitude conversion relationships. Linear Standard Regression (SR) relations fail when both the magnitudes have measurement errors. To accomplish homogenization, techniques like Orthogonal Standard Regression (OSR) are thus used. In this paper a technique is proposed for using such OSR for preparation of homogenized earthquake catalog in moment magnitude Mw. For derivation of orthogonal regression relation between mb and Mw, a data set consisting of 171 events with observed body wave magnitudes (mb,obs) and moment magnitude (Mw,obs) values has been taken from ISC and GCMT databases for Northeast India and adjoining region for the period 1978-2006. Firstly, an OSR relation given below has been developed using mb,obs and Mw,obs values corresponding to 150 events from this data set. M=1.3(±0.004)m-1.4(±0.130), where mb,proxy are body wave magnitude values of the points on the OSR line given by the orthogonality criterion, for observed (mb,obs, Mw,obs) points. A linear relation is then developed between these 150 mb,obs values and corresponding mb,proxy values given by the OSR line using orthogonality criterion. The relation obtained is m=0.878(±0.03)m+0.653(±0.15). The accuracy of the above procedure has been checked with the rest of the data i.e., 21 events values. The improvement in the correlation coefficient value between mb,obs and Mw estimated using the proposed procedure compared to the correlation coefficient value between mb,obs and Mw,obs shows the advantage of OSR relationship for homogenization. The OSR procedure developed in this study can be used to homogenize any catalog containing various magnitudes (e.g., ML, mb, MS) with measurement errors, by their conversion to unified moment magnitude Mw. The proposed procedure also remains valid in case the magnitudes have measurement errors of different orders, i.e. the error variance ratio is

  9. Absolute magnitudes by statistical parallaxes

    International Nuclear Information System (INIS)

    Heck, A.

    1978-01-01

    The author describes an algorithm for stellar luminosity calibrations (based on the principle of maximum likelihood) which allows the calibration of relations of the type: Msub(i)=sup(N)sub(j=1)Σqsub(j)Csub(ij), i=1,...,n, where n is the size of the sample at hand, Msub(i) are the individual absolute magnitudes, Csub(ij) are observational quantities (j=1,...,N), and qsub(j) are the coefficients to be determined. If one puts N=1 and Csub(iN)=1, one has q 1 =M(mean), the mean absolute magnitude of the sample. As additional output, the algorithm provides one also with the dispersion in magnitude of the sample sigmasub(M), the mean solar motion (U,V,W) and the corresponding velocity ellipsoid (sigmasub(u), sigmasub(v), sigmasub(w). The use of this algorithm is illustrated. (Auth.)

  10. Understanding Magnitudes to Understand Fractions

    Science.gov (United States)

    Gabriel, Florence

    2016-01-01

    Fractions are known to be difficult to learn and difficult to teach, yet they are vital for students to have access to further mathematical concepts. This article uses evidence to support teachers employing teaching methods that focus on the conceptual understanding of the magnitude of fractions.

  11. The language of magnitude comparison

    OpenAIRE

    Matthews, William John; Dylman, Alexandra S

    2014-01-01

    When two objects differ in magnitude, their relation can be described with a "smaller" comparative (e.g., "less", "shorter", "lower") or a "larger" comparative (e.g., "more", "taller", "higher"). We show that, across multiple dimensions and tasks, English speakers preferentially use the latter. In sentence-completion tasks, this higher use of larger comparatives (HULC) effect is more pronounced when the larger item is presented on the left (for simultaneous presentation) or second (for sequen...

  12. Radiation doses - maps and magnitudes

    International Nuclear Information System (INIS)

    1989-01-01

    A NRPB leaflet in the 'At-a-Glance' Series presents information on the numerous sources and magnitude of exposure of man to radiation. These include the medical use of radiation, radioactive discharges to the environment, cosmic rays, gamma rays from the ground and buildings, radon gas and food and drink. A Pie chart represents the percentage contribution of each of those sources. Finally, the terms becquerel, microsievert and millisievert are explained. (U.K.)

  13. Solar Variability Magnitudes and Timescales

    Science.gov (United States)

    Kopp, Greg

    2015-08-01

    The Sun’s net radiative output varies on timescales of minutes to many millennia. The former are directly observed as part of the on-going 37-year long total solar irradiance climate data record, while the latter are inferred from solar proxy and stellar evolution models. Since the Sun provides nearly all the energy driving the Earth’s climate system, changes in the sunlight reaching our planet can have - and have had - significant impacts on life and civilizations.Total solar irradiance has been measured from space since 1978 by a series of overlapping instruments. These have shown changes in the spatially- and spectrally-integrated radiant energy at the top of the Earth’s atmosphere from timescales as short as minutes to as long as a solar cycle. The Sun’s ~0.01% variations over a few minutes are caused by the superposition of convection and oscillations, and even occasionally by a large flare. Over days to weeks, changing surface activity affects solar brightness at the ~0.1% level. The 11-year solar cycle has comparable irradiance variations with peaks near solar maxima.Secular variations are harder to discern, being limited by instrument stability and the relatively short duration of the space-borne record. Proxy models of the Sun based on cosmogenic isotope records and inferred from Earth climate signatures indicate solar brightness changes over decades to millennia, although the magnitude of these variations depends on many assumptions. Stellar evolution affects yet longer timescales and is responsible for the greatest solar variabilities.In this talk I will summarize the Sun’s variability magnitudes over different temporal ranges, showing examples relevant for climate studies as well as detections of exo-solar planets transiting Sun-like stars.

  14. Scaling Relations of Local Magnitude versus Moment Magnitude for Sequences of Similar Earthquakes in Switzerland

    KAUST Repository

    Bethmann, F.; Deichmann, N.; Mai, Paul Martin

    2011-01-01

    Theoretical considerations and empirical regressions show that, in the magnitude range between 3 and 5, local magnitude, ML, and moment magnitude, Mw, scale 1:1. Previous studies suggest that for smaller magnitudes this 1:1 scaling breaks down

  15. Magnitude determination for large underground nuclear explosions

    Energy Technology Data Exchange (ETDEWEB)

    Porter, Lawrence D [Lawrence Radiation Laboratory, University of California, Livermore, CA (United States)

    1970-05-15

    A method is presented for determining the local magnitudes for large underground nuclear explosions. The Gutenberg-Richter nomograph is applied to the peak amplitudes for 24 large underground nuclear explosions that took place in Nevada. The amplitudes were measured at 18 California Wood-Anderson stations located 150-810 km from the explosion epicenter. The variation of the individual station magnitudes and magnitude corrections and the variation of the average and rms error estimates in the magnitude determinations are examined with respect to distance, azimuth, and event location. The magnitude prediction capability of the Gutenberg-Richter nomograph is examined on the basis of these two criteria, and certain corrections are suggested. The azimuthal dependence of the individual station magnitudes is investigated, and corrections for the California stations are calculated. Statistical weighting schemes for two-component data are employed, and the assumptions and limitations in the use of peak amplitudes are discussed. (author)

  16. Extreme value distribution of earthquake magnitude

    Science.gov (United States)

    Zi, Jun Gan; Tung, C. C.

    1983-07-01

    Probability distribution of maximum earthquake magnitude is first derived for an unspecified probability distribution of earthquake magnitude. A model for energy release of large earthquakes, similar to that of Adler-Lomnitz and Lomnitz, is introduced from which the probability distribution of earthquake magnitude is obtained. An extensive set of world data for shallow earthquakes, covering the period from 1904 to 1980, is used to determine the parameters of the probability distribution of maximum earthquake magnitude. Because of the special form of probability distribution of earthquake magnitude, a simple iterative scheme is devised to facilitate the estimation of these parameters by the method of least-squares. The agreement between the empirical and derived probability distributions of maximum earthquake magnitude is excellent.

  17. Numerical Magnitude Representations Influence Arithmetic Learning

    Science.gov (United States)

    Booth, Julie L.; Siegler, Robert S.

    2008-01-01

    This study examined whether the quality of first graders' (mean age = 7.2 years) numerical magnitude representations is correlated with, predictive of, and causally related to their arithmetic learning. The children's pretest numerical magnitude representations were found to be correlated with their pretest arithmetic knowledge and to be…

  18. Representations of the Magnitudes of Fractions

    Science.gov (United States)

    Schneider, Michael; Siegler, Robert S.

    2010-01-01

    We tested whether adults can use integrated, analog, magnitude representations to compare the values of fractions. The only previous study on this question concluded that even college students cannot form such representations and instead compare fraction magnitudes by representing numerators and denominators as separate whole numbers. However,…

  19. Magnitude of localized magnetic moments in metals

    International Nuclear Information System (INIS)

    Kiwi, M.; Pestana, E.; Ramirez, R.

    1979-01-01

    The magnitude of the localized magnetic moment of a transition or rare earth element impurity in a metal is evaluated within the framework of the Anderson model. Rotational invariance is preserved throughout. Graphs of the magnitude of the magnetization as a function of the relevant parameters of the model are provided and discussed. (author)

  20. Local magnitudes of small contained explosions.

    Energy Technology Data Exchange (ETDEWEB)

    Chael, Eric Paul

    2009-12-01

    The relationship between explosive yield and seismic magnitude has been extensively studied for underground nuclear tests larger than about 1 kt. For monitoring smaller tests over local ranges (within 200 km), we need to know whether the available formulas can be extrapolated to much lower yields. Here, we review published information on amplitude decay with distance, and on the seismic magnitudes of industrial blasts and refraction explosions in the western U. S. Next we measure the magnitudes of some similar shots in the northeast. We find that local magnitudes ML of small, contained explosions are reasonably consistent with the magnitude-yield formulas developed for nuclear tests. These results are useful for estimating the detection performance of proposed local seismic networks.

  1. Discounting Behaviour and the Magnitude Effect

    DEFF Research Database (Denmark)

    Andersen, Steffen; Harrison, Glenn W.; Lau, Morten Igel

    2013-01-01

    We evaluate the claim that individuals exhibit a magnitude effect in their discounting behaviour, where higher discount rates are inferred from choices made with lower principals, all else being equal. If the magnitude effect is quantitatively significant, it is not appropriate to use one discount...... rate that is independent of the scale of the project for cost–benefit analysis and capital budgeting. Using data from a field experiment in Denmark, we find statistically significant evidence of a magnitude effect that is much smaller than is claimed. This evidence surfaces only if one controls...

  2. Determination of the Meteor Limiting Magnitude

    Science.gov (United States)

    Kingery, A.; Blaauw, R.; Cooke, W. J.

    2016-01-01

    The limiting meteor magnitude of a meteor camera system will depend on the camera hardware and software, sky conditions, and the location of the meteor radiant. Some of these factors are constants for a given meteor camera system, but many change between meteor shower or sporadic source and on both long and short timescales. Since the limiting meteor magnitude ultimately gets used to calculate the limiting meteor mass for a given data set, it is important to have an understanding of these factors and to monitor how they change throughout the night, as a 0.5 magnitude uncertainty in limiting magnitude translates to a uncertainty in limiting mass by a factor of two.

  3. The Magnitude of Atherogenic Dyslipidaemia among Geriatric ...

    African Journals Online (AJOL)

    The Magnitude of Atherogenic Dyslipidaemia among Geriatric Nigerians with ... June 2011 on 122 consecutive geriatric patients with systemic hypertension ... of dyslipidaemia and a marker of dyslipidaemic cardiometabolic risk among them.

  4. Measuring radon source magnitude in residential buildings

    International Nuclear Information System (INIS)

    Nazaroff, W.W.; Boegel, M.L.; Nero, A.V.

    1981-08-01

    A description is given of procedures used in residences for rapid grab-sample and time-dependent measurements of the air-exchange rate and radon concentration. The radon source magnitude is calculated from the results of simultaneous measurements of these parameters. Grab-sample measurements in three survey groups comprising 101 US houses showed the radon source magnitude to vary approximately log-normally with a geometric mean of 0.37 and a range of 0.01 to 6.0 pCi 1 -1 h -1 . Successive measurements in six houses in the northeastern United States showed considerable variability in source magnitude within a given house. In two of these houses the source magnitude showed a strong correlation with the air-exchange rate, suggesting that soil gas influx can be an important transport process for indoor radon

  5. Asymmetry in power-law magnitude correlations.

    Science.gov (United States)

    Podobnik, Boris; Horvatić, Davor; Tenenbaum, Joel N; Stanley, H Eugene

    2009-07-01

    Time series of increments can be created in a number of different ways from a variety of physical phenomena. For example, in the phenomenon of volatility clustering-well-known in finance-magnitudes of adjacent increments are correlated. Moreover, in some time series, magnitude correlations display asymmetry with respect to an increment's sign: the magnitude of |x_{i}| depends on the sign of the previous increment x_{i-1} . Here we define a model-independent test to measure the statistical significance of any observed asymmetry. We propose a simple stochastic process characterized by a an asymmetry parameter lambda and a method for estimating lambda . We illustrate both the test and process by analyzing physiological data.

  6. Local magnitude, duration magnitude and seismic moment of Dahshour 1992 earthquakes

    Directory of Open Access Journals (Sweden)

    M. F. Abdelwahed

    2000-06-01

    Full Text Available Local magnitudes ML have been calculated for 56 earthquakes of the Dahshour 1992 sequence using simulated records of the KEG broadband station and the estimated calibration function of the Dahshour area. These were compared with their corresponding values of duration magnitudes obtained from the analog short period seismograms of the HLW station. The local magnitudes M L and the duration magnitudes M D for this region imply a linear relation as follows: M L = 1.2988 (± 0.04 M D – 0.9032 (± 0.14. Seismic moment has also been estimated for these events using simple measurements from the time domain records. These measurements based on the simulated Wood Anderson seismograms are used for the local magnitude (ML estimation. The derived relationship between seismic moment (M 0 and magnitude (M L is: log (M 0 = 0.954 (± 0.019 M L + 17.258 (± 0.075.

  7. The moment magnitude Mw and the energy magnitude Me: common roots and differences

    OpenAIRE

    2010-01-01

    Abstract Starting from the classical empirical magnitude-energy relationships, in this article, the derivation of the modern scales for moment magnitude Mw and energy magnitude Me is outlined and critically discussed. The formulas for Mw and Me calculation are presented in a way that reveals, besides the contributions of the physically defined measurement parameters seismic moment M0 and radiated seismic energy ES, the role of the constants in the classical Gutenberg?Richter magnit...

  8. Colour-magnitude diagram of NGC 5053

    Energy Technology Data Exchange (ETDEWEB)

    Walker, M F; Pike, C D [California Univ., Santa Cruz (USA). Lick Observatory; McGee, J D

    1976-06-01

    The colour-magnitude diagram of NGC 5053 has been derived to V = 21.1 from photographic and electronographic observations. The electronographic observations were obtained with an experimental Spectracon image-converter, having photocathode and exit window dimensions of 20 x 30 mm, mounted at the prime-focus of the 120-in. Lick reflector. The photographic observations were obtained with the 20-in. Carnegie astrograph and the 36-in. Crossley reflector. The colour-magnitude diagram resembles that of M92, with the difference that a red horizontal branch is more pronounced than the asymptotic branch in NGC 5053. The topology of the horizontal branch is that of clusters with an intermediate metal content and is thus at variance with the mean period of the RR Lyr stars and the unreddened colour of the subgiant branch read at the magnitude level of the horizontal branch, both of which would indicate an extremely low metal content. If comparison of the colour-magnitude diagrams of NGC 5053 and M92 is valid, then the reddening of NGC 5053 is Esub(B-V) = 0.02 and the apparent distance modulus is m-M = 16.08 +- 0.08.

  9. Historical revision of the exposure magnitude and the dosimetric magnitudes used in radiological protection; Revision historica de la magnitud exposicion y las magnitudes dosimetricas empleadas en proteccion radiologica

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez J, F. [UNAM, Facultad de Ciencias, Ciudad Universitaria, 04510 Mexico D. F. (Mexico); Alvarez R, J. T., E-mail: trinidad.alvarez@inin.gob.mx [ININ, Departamento de Metrologia de Radiaciones Ionizantes, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2014-10-15

    In this work a historical revision of the exposure magnitude development and their roentgen unit (1905 - 2011) is made, noting that it had their origin in the electric methods for the detection of the ionizing radiation in the period of 1895 at 1937. However, the ionization is not who better characterizes the physical, chemical and biological effects of the ionizing radiations, but is the energy deposited by this radiation in the interest bodies, which led historically to the development of dosimetric magnitudes in energy terms like they are: the absorbed dose D (1950), the kerma K (1958) and the equivalent dose H (1962). These dosimetric magnitudes culminated with the definition of the effective equivalent dose or effective dose which is not measurable and should be considered with the operative magnitudes ICRU: H environmental equivalent dose and/or H directional equivalent dose, which can be determined by means of a conversion coefficient that is applied to the exposure, kerma in air, fluence, etc. (Author)

  10. Interaction of Number Magnitude and Auditory Localization.

    Science.gov (United States)

    Golob, Edward J; Lewald, Jörg; Jungilligens, Johannes; Getzmann, Stephan

    2016-01-01

    The interplay of perception and memory is very evident when we perceive and then recognize familiar stimuli. Conversely, information in long-term memory may also influence how a stimulus is perceived. Prior work on number cognition in the visual modality has shown that in Western number systems long-term memory for the magnitude of smaller numbers can influence performance involving the left side of space, while larger numbers have an influence toward the right. Here, we investigated in the auditory modality whether a related effect may bias the perception of sound location. Subjects (n = 28) used a swivel pointer to localize noise bursts presented from various azimuth positions. The noise bursts were preceded by a spoken number (1-9) or, as a nonsemantic control condition, numbers that were played in reverse. The relative constant error in noise localization (forward minus reversed speech) indicated a systematic shift in localization toward more central locations when the number was smaller and toward more peripheral positions when the preceding number magnitude was larger. These findings do not support the traditional left-right number mapping. Instead, the results may reflect an overlap between codes for number magnitude and codes for sound location as implemented by two channel models of sound localization, or possibly a categorical mapping stage of small versus large magnitudes. © The Author(s) 2015.

  11. Incentive theory: IV. Magnitude of reward

    OpenAIRE

    Killeen, Peter R.

    1985-01-01

    Incentive theory is successfully applied to data from experiments in which the amount of food reward is varied. This is accomplished by assuming that incentive value is a negatively accelerated function of reward duration. The interaction of the magnitude of a reward with its delay is confirmed, and the causes and implications of this interaction are discussed.

  12. Local magnitude, duration magnitude and seismic moment of Dahshour 1992 earthquakes

    OpenAIRE

    M. F. Abdelwahed; E. M. Abdelrahman; H. M. Hussein; M. M. Dessokey

    2000-01-01

    Local magnitudes ML have been calculated for 56 earthquakes of the Dahshour 1992 sequence using simulated records of the KEG broadband station and the estimated calibration function of the Dahshour area. These were compared with their corresponding values of duration magnitudes obtained from the analog short period seismograms of the HLW station. The local magnitudes M L and the duration magnitudes M D for this region imply a linear relation as follows: M L = 1.2988 (± 0.04) M D – 0.9032 (± 0...

  13. Absolute-magnitude distributions of supernovae

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, Dean; Wright, John [Department of Physics, Xavier University of Louisiana, New Orleans, LA 70125 (United States); Jenkins III, Robert L. [Applied Physics Department, Richard Stockton College, Galloway, NJ 08205 (United States); Maddox, Larry, E-mail: drichar7@xula.edu [Department of Chemistry and Physics, Southeastern Louisiana University, Hammond, LA 70402 (United States)

    2014-05-01

    The absolute-magnitude distributions of seven supernova (SN) types are presented. The data used here were primarily taken from the Asiago Supernova Catalogue, but were supplemented with additional data. We accounted for both foreground and host-galaxy extinction. A bootstrap method is used to correct the samples for Malmquist bias. Separately, we generate volume-limited samples, restricted to events within 100 Mpc. We find that the superluminous events (M{sub B} < –21) make up only about 0.1% of all SNe in the bias-corrected sample. The subluminous events (M{sub B} > –15) make up about 3%. The normal Ia distribution was the brightest with a mean absolute blue magnitude of –19.25. The IIP distribution was the dimmest at –16.75.

  14. Magnitudes and units in radiation protection

    International Nuclear Information System (INIS)

    2005-01-01

    This sheet provides definition and information on the ionizing radiations, the measurement of a ionizing radiation magnitude by a radioactive source (the becquerel), the measurement of the ionizing radiation energy absorbed by the organism (the gray), the biological impact evaluation of ionizing radiations in function of their nature (the sievert) and the evaluation and comparison of biological risks bond to little doses (dose efficiency). (A.L.B.)

  15. Improving Children's Knowledge of Fraction Magnitudes.

    Directory of Open Access Journals (Sweden)

    Lisa K Fazio

    Full Text Available We examined whether playing a computerized fraction game, based on the integrated theory of numerical development and on the Common Core State Standards' suggestions for teaching fractions, would improve children's fraction magnitude understanding. Fourth and fifth-graders were given brief instruction about unit fractions and played Catch the Monster with Fractions, a game in which they estimated fraction locations on a number line and received feedback on the accuracy of their estimates. The intervention lasted less than 15 minutes. In our initial study, children showed large gains from pretest to posttest in their fraction number line estimates, magnitude comparisons, and recall accuracy. In a more rigorous second study, the experimental group showed similarly large improvements, whereas a control group showed no improvement from practicing fraction number line estimates without feedback. The results provide evidence for the effectiveness of interventions emphasizing fraction magnitudes and indicate how psychological theories and research can be used to evaluate specific recommendations of the Common Core State Standards.

  16. Scaling Relations of Local Magnitude versus Moment Magnitude for Sequences of Similar Earthquakes in Switzerland

    KAUST Repository

    Bethmann, F.

    2011-03-22

    Theoretical considerations and empirical regressions show that, in the magnitude range between 3 and 5, local magnitude, ML, and moment magnitude, Mw, scale 1:1. Previous studies suggest that for smaller magnitudes this 1:1 scaling breaks down. However, the scatter between ML and Mw at small magnitudes is usually large and the resulting scaling relations are therefore uncertain. In an attempt to reduce these uncertainties, we first analyze the ML versus Mw relation based on 195 events, induced by the stimulation of a geothermal reservoir below the city of Basel, Switzerland. Values of ML range from 0.7 to 3.4. From these data we derive a scaling of ML ~ 1:5Mw over the given magnitude range. We then compare peak Wood-Anderson amplitudes to the low-frequency plateau of the displacement spectra for six sequences of similar earthquakes in Switzerland in the range of 0:5 ≤ ML ≤ 4:1. Because effects due to the radiation pattern and to the propagation path between source and receiver are nearly identical at a particular station for all events in a given sequence, the scatter in the data is substantially reduced. Again we obtain a scaling equivalent to ML ~ 1:5Mw. Based on simulations using synthetic source time functions for different magnitudes and Q values estimated from spectral ratios between downhole and surface recordings, we conclude that the observed scaling can be explained by attenuation and scattering along the path. Other effects that could explain the observed magnitude scaling, such as a possible systematic increase of stress drop or rupture velocity with moment magnitude, are masked by attenuation along the path.

  17. Strong motion duration and earthquake magnitude relationships

    International Nuclear Information System (INIS)

    Salmon, M.W.; Short, S.A.; Kennedy, R.P.

    1992-06-01

    Earthquake duration is the total time of ground shaking from the arrival of seismic waves until the return to ambient conditions. Much of this time is at relatively low shaking levels which have little effect on seismic structural response and on earthquake damage potential. As a result, a parameter termed ''strong motion duration'' has been defined by a number of investigators to be used for the purpose of evaluating seismic response and assessing the potential for structural damage due to earthquakes. This report presents methods for determining strong motion duration and a time history envelope function appropriate for various evaluation purposes, for earthquake magnitude and distance, and for site soil properties. There are numerous definitions of strong motion duration. For most of these definitions, empirical studies have been completed which relate duration to earthquake magnitude and distance and to site soil properties. Each of these definitions recognizes that only the portion of an earthquake record which has sufficiently high acceleration amplitude, energy content, or some other parameters significantly affects seismic response. Studies have been performed which indicate that the portion of an earthquake record in which the power (average rate of energy input) is maximum correlates most closely with potential damage to stiff nuclear power plant structures. Hence, this report will concentrate on energy based strong motion duration definitions

  18. Sequential dependencies in magnitude scaling of loudness

    DEFF Research Database (Denmark)

    Joshi, Suyash Narendra; Jesteadt, Walt

    2013-01-01

    Ten normally hearing listeners used a programmable sone-potentiometer knob to adjust the level of a 1000-Hz sinusoid to match the loudness of numbers presented to them in a magnitude production task. Three different power-law exponents (0.15, 0.30, and 0.60) and a log-law with equal steps in d......B were used to program the sone-potentiometer. The knob settings systematically influenced the form of the loudness function. Time series analysis was used to assess the sequential dependencies in the data, which increased with increasing exponent and were greatest for the log-law. It would be possible......, therefore, to choose knob properties that minimized these dependencies. When the sequential dependencies were removed from the data, the slope of the loudness functions did not change, but the variability decreased. Sequential dependencies were only present when the level of the tone on the previous trial...

  19. Erratum: Sloan Magnitudes for the Brightest Stars

    Science.gov (United States)

    Mallama, A.

    2018-06-01

    In the article "Sloan Magnitudes for the Brightest Stars" (JAAVSO, 2014, 42, 443), Equation 3 in section A.1. of the Appendix is incorrect; the coefficient of ((R-I) - C1) should be 0.935, rather than 0.953. The mean differences between the new and old results are 0.00 in all cases, and the standard deviations are all 0.00 or 0.01, which is less than the photometric uncertainties of the Johnson or Sloan values. A revised version of the catalog has been published at https://arxiv.org/abs/1805.09324. The revision is proposed as a bright star extension to the APASS database.

  20. Violence against women: global scope and magnitude.

    Science.gov (United States)

    Watts, Charlotte; Zimmerman, Cathy

    2002-04-06

    An increasing amount of research is beginning to offer a global overview of the extent of violence against women. In this paper we discuss the magnitude of some of the most common and most severe forms of violence against women: intimate partner violence; sexual abuse by non-intimate partners; trafficking, forced prostitution, exploitation of labour, and debt bondage of women and girls; physical and sexual violence against prostitutes; sex selective abortion, female infanticide, and the deliberate neglect of girls; and rape in war. There are many potential perpetrators, including spouses and partners, parents, other family members, neighbours, and men in positions of power or influence. Most forms of violence are not unique incidents but are ongoing, and can even continue for decades. Because of the sensitivity of the subject, violence is almost universally under-reported. Nevertheless, the prevalence of such violence suggests that globally, millions of women are experiencing violence or living with its consequences.

  1. Evidence accumulation in the magnitude system.

    Directory of Open Access Journals (Sweden)

    Anna Lambrechts

    Full Text Available Perceptual interferences in the estimation of quantities (time, space and numbers have been interpreted as evidence for a common magnitude system. However, if duration estimation has appears sensitive to spatial and numerical interferences, space and number estimation tend to be resilient to temporal manipulations. These observations question the relative contribution of each quantity in the elaboration of a representation in a common mental metric. Here, we elaborated a task in which perceptual evidence accumulated over time for all tested quantities (space, time and number in order to match the natural requirement for building a duration percept. For this, we used a bisection task. Experimental trials consisted of dynamic dots of different sizes appearing progressively on the screen. Participants were asked to judge the duration, the cumulative surface or the number of dots in the display while the two non-target dimensions varied independently. In a prospective experiment, participants were informed before the trial which dimension was the target; in a retrospective experiment, participants had to attend to all dimensions and were informed only after a given trial which dimension was the target. Surprisingly, we found that duration was resilient to spatial and numerical interferences whereas space and number estimation were affected by time. Specifically, and counter-intuitively, results revealed that longer durations lead to smaller number and space estimates whether participants knew before (prospectively or after (retrospectively a given trial which quantity they had to estimate. Altogether, our results support a magnitude system in which perceptual evidence for time, space and numbers integrate following Bayesian cue-combination rules.

  2. Child prostitution: magnitude and related problems.

    Science.gov (United States)

    Ayalew, T; Berhane, Y

    2000-07-01

    In Ethiopia, very little is known about prostitution in general and about child prostitution in particular. The objective of this study was to determine the magnitude of child prostitution and to identify problems associated with it. A cross-sectional study design was utilized. Data were collected using structured questionnaire. A total of 650 commercial sex workers were interviewed. Eighty eight (13.5%) were below the age of 18 years at the time of data collection. At the time of joining prostitution 268 (41.2%) were under 18 years of age. Poverty, disagreement with family, and peer influence were the major reasons leading to prostitution. Child prostitutes were likely to be victim of physical violence [OR = (95% C.I.) = 1.93(1.18,3.15)] and sexual violence [OR = (95% C.I.) = 2.20(1.36,3.35)] compared to adult prostitutes. Child prostitutes were about five times more likely to desire rejoining their family than the adult prostitutes [OR = (95% C.I) = 5.47(3.01;9.93)]. Strategies need to be developed to rescue child prostitutes from on-job violence, and to establish a rehabilitation program for those interested to discontinue prostitution along with efforts to minimize entry into prostitution.

  3. Childhood Cataract: Magnitude, Management, Economics and Impact

    Directory of Open Access Journals (Sweden)

    BR Shamanna

    2004-01-01

    Full Text Available The prevalence of blindness among children in different regions varies from 0.2/1000 children to over 1.5/1000 children with a global figure estimated at 0.7/1000. This means that there are an estimated 1.4 million blind children worldwide.1 The proportion of blindness in children due to cataract varies considerably between regions from 10%-30% with a global average estimated at 14%, giving 190,000 children blind from cataract. 2 While the magnitude of childhood cataracts varies from place to place, it is a priority within all blindness control programmes for children. Children who are blind have to overcome a lifetime of emotional, social and economic difficulties which affect the child, the family and society.3 Loss of vision in children influences their education, employment and social life. The numbers blind with cataract do not reflect the years of disability and lost quality of life. Childhood blindness is second only to adult cataract as a cause of blind-person years. Approximately 70 million blind-person years are caused by childhood blindness of which about 10 million blind-person years (14% is due to childhood cataract. Timely recognition and intervention can eliminate blind-years due to childhood cataract, as the condition is treatable.

  4. How fault geometry controls earthquake magnitude

    Science.gov (United States)

    Bletery, Q.; Thomas, A.; Karlstrom, L.; Rempel, A. W.; Sladen, A.; De Barros, L.

    2016-12-01

    Recent large megathrust earthquakes, such as the Mw9.3 Sumatra-Andaman earthquake in 2004 and the Mw9.0 Tohoku-Oki earthquake in 2011, astonished the scientific community. The first event occurred in a relatively low-convergence-rate subduction zone where events of its size were unexpected. The second event involved 60 m of shallow slip in a region thought to be aseismicaly creeping and hence incapable of hosting very large magnitude earthquakes. These earthquakes highlight gaps in our understanding of mega-earthquake rupture processes and the factors controlling their global distribution. Here we show that gradients in dip angle exert a primary control on mega-earthquake occurrence. We calculate the curvature along the major subduction zones of the world and show that past mega-earthquakes occurred on flat (low-curvature) interfaces. A simplified analytic model demonstrates that shear strength heterogeneity increases with curvature. Stress loading on flat megathrusts is more homogeneous and hence more likely to be released simultaneously over large areas than on highly-curved faults. Therefore, the absence of asperities on large faults might counter-intuitively be a source of higher hazard.

  5. Local magnitude, duration magnitude and seismic moment of Dahshour 1992 earthquakes

    Energy Technology Data Exchange (ETDEWEB)

    Dessokey, M.M.; Abdelwahed, M.F. [National research Institute of Astronomy and Geophysics, Cairo (Egypt). Dept. of Seismology; Hussein, H.M.; Abdelrahman, El. M. [Cairo Univ., Cairo (Egypt). Dept. of Geophysics

    2000-02-01

    Local magnitude M{sub L} have been calculated for 56 earthquakes of the Dahshour 1992 sequence using simulated records of the KEG broadband station and estimated calibration function of the area. The measurements, derived by the simulated Wood Anderson seismograms, are analysed and discussed.

  6. Historical revision of the exposure magnitude and the dosimetric magnitudes used in radiological protection

    International Nuclear Information System (INIS)

    Gonzalez J, F.; Alvarez R, J. T.

    2014-10-01

    In this work a historical revision of the exposure magnitude development and their roentgen unit (1905 - 2011) is made, noting that it had their origin in the electric methods for the detection of the ionizing radiation in the period of 1895 at 1937. However, the ionization is not who better characterizes the physical, chemical and biological effects of the ionizing radiations, but is the energy deposited by this radiation in the interest bodies, which led historically to the development of dosimetric magnitudes in energy terms like they are: the absorbed dose D (1950), the kerma K (1958) and the equivalent dose H (1962). These dosimetric magnitudes culminated with the definition of the effective equivalent dose or effective dose which is not measurable and should be considered with the operative magnitudes ICRU: H environmental equivalent dose and/or H directional equivalent dose, which can be determined by means of a conversion coefficient that is applied to the exposure, kerma in air, fluence, etc. (Author)

  7. The moment magnitude M w and the energy magnitude M e: common roots and differences

    Science.gov (United States)

    Bormann, Peter; di Giacomo, Domenico

    2011-04-01

    Starting from the classical empirical magnitude-energy relationships, in this article, the derivation of the modern scales for moment magnitude M w and energy magnitude M e is outlined and critically discussed. The formulas for M w and M e calculation are presented in a way that reveals, besides the contributions of the physically defined measurement parameters seismic moment M 0 and radiated seismic energy E S, the role of the constants in the classical Gutenberg-Richter magnitude-energy relationship. Further, it is shown that M w and M e are linked via the parameter Θ = log( E S/ M 0), and the formula for M e can be written as M e = M w + (Θ + 4.7)/1.5. This relationship directly links M e with M w via their common scaling to classical magnitudes and, at the same time, highlights the reason why M w and M e can significantly differ. In fact, Θ is assumed to be constant when calculating M w. However, variations over three to four orders of magnitude in stress drop Δ σ (as well as related variations in rupture velocity V R and seismic wave radiation efficiency η R) are responsible for the large variability of actual Θ values of earthquakes. As a result, for the same earthquake, M e may sometimes differ by more than one magnitude unit from M w. Such a difference is highly relevant when assessing the actual damage potential associated with a given earthquake, because it expresses rather different static and dynamic source properties. While M w is most appropriate for estimating the earthquake size (i.e., the product of rupture area times average displacement) and thus the potential tsunami hazard posed by strong and great earthquakes in marine environs, M e is more suitable than M w for assessing the potential hazard of damage due to strong ground shaking, i.e., the earthquake strength. Therefore, whenever possible, these two magnitudes should be both independently determined and jointly considered. Usually, only M w is taken as a unified magnitude in many

  8. Automatic computation of moment magnitudes for small earthquakes and the scaling of local to moment magnitude

    Science.gov (United States)

    Edwards, Benjamin; Allmann, Bettina; Fäh, Donat; Clinton, John

    2010-10-01

    Moment magnitudes (MW) are computed for small and moderate earthquakes using a spectral fitting method. 40 of the resulting values are compared with those from broadband moment tensor solutions and found to match with negligible offset and scatter for available MW values of between 2.8 and 5.0. Using the presented method, MW are computed for 679 earthquakes in Switzerland with a minimum ML = 1.3. A combined bootstrap and orthogonal L1 minimization is then used to produce a scaling relation between ML and MW. The scaling relation has a polynomial form and is shown to reduce the dependence of the predicted MW residual on magnitude relative to an existing linear scaling relation. The computation of MW using the presented spectral technique is fully automated at the Swiss Seismological Service, providing real-time solutions within 10 minutes of an event through a web-based XML database. The scaling between ML and MW is explored using synthetic data computed with a stochastic simulation method. It is shown that the scaling relation can be explained by the interaction of attenuation, the stress-drop and the Wood-Anderson filter. For instance, it is shown that the stress-drop controls the saturation of the ML scale, with low-stress drops (e.g. 0.1-1.0 MPa) leading to saturation at magnitudes as low as ML = 4.

  9. Moment Magnitude ( M W) and Local Magnitude ( M L) Relationship for Earthquakes in Northeast India

    Science.gov (United States)

    Baruah, Santanu; Baruah, Saurabh; Bora, P. K.; Duarah, R.; Kalita, Aditya; Biswas, Rajib; Gogoi, N.; Kayal, J. R.

    2012-11-01

    An attempt has been made to examine an empirical relationship between moment magnitude ( M W) and local magnitude ( M L) for the earthquakes in the northeast Indian region. Some 364 earthquakes that were recorded during 1950-2009 are used in this study. Focal mechanism solutions of these earthquakes include 189 Harvard-CMT solutions ( M W ≥ 4.0) for the period 1976-2009, 61 published solutions and 114 solutions obtained for the local earthquakes (2.0 ≤ M L ≤ 5.0) recorded by a 27-station permanent broadband network during 2001-2009 in the region. The M W- M L relationships in seven selected zones of the region are determined by linear regression analysis. A significant variation in the M W- M L relationship and its zone specific dependence are reported here. It is found that M W is equivalent to M L with an average uncertainty of about 0.13 magnitude units. A single relationship is, however, not adequate to scale the entire northeast Indian region because of heterogeneous geologic and geotectonic environments where earthquakes occur due to collisions, subduction and complex intra-plate tectonics.

  10. Temporal and spatial variations in the magnitude of completeness ...

    Indian Academy of Sciences (India)

    Temporal and spatial variations in the magnitude of completeness for homogenized moment magnitude catalogue for northeast India. Ranjit Das H R ... Orthogonal regression relations for conversion of body and surface wave magnitudes to w,HRVD based on events data for the period 1978–2006 have been derived.

  11. Automatic computation of moment magnitudes for small earthquakes and the scaling of local to moment magnitude

    OpenAIRE

    Edwards, Benjamin; Allmann, Bettina; Fäh, Donat; Clinton, John

    2017-01-01

    Moment magnitudes (MW) are computed for small and moderate earthquakes using a spectral fitting method. 40 of the resulting values are compared with those from broadband moment tensor solutions and found to match with negligible offset and scatter for available MW values of between 2.8 and 5.0. Using the presented method, MW are computed for 679 earthquakes in Switzerland with a minimum ML= 1.3. A combined bootstrap and orthogonal L1 minimization is then used to produce a scaling relation bet...

  12. Magnitudes and frequencies of earthquakes in relation to seismic risk

    International Nuclear Information System (INIS)

    Sharma, R.D.

    1989-01-01

    Estimating the frequencies of occurrence of earthquakes of different magnitudes on a regional basis is an important task in estimating seismic risk at a construction site. Analysis of global earthquake data provides an insight into the magnitudes frequency relationship in a statistical manner. It turns out that, whereas a linear relationship between the logarithm of earthquake occurrence rates and the corresponding earthquake magnitudes fits well in the magnitude range between 5 and 7, a second degree polynomial in M, the earthquake magnitude provides a better description of the frequencies of earthquakes in a much wider range of magnitudes. It may be possible to adopt magnitude frequency relation for regions, for which adequate earthquake data are not available, to carry out seismic risk calculations. (author). 32 refs., 8 tabs., 7 figs

  13. Magnitude Estimation for Large Earthquakes from Borehole Recordings

    Science.gov (United States)

    Eshaghi, A.; Tiampo, K. F.; Ghofrani, H.; Atkinson, G.

    2012-12-01

    We present a simple and fast method for magnitude determination technique for earthquake and tsunami early warning systems based on strong ground motion prediction equations (GMPEs) in Japan. This method incorporates borehole strong motion records provided by the Kiban Kyoshin network (KiK-net) stations. We analyzed strong ground motion data from large magnitude earthquakes (5.0 ≤ M ≤ 8.1) with focal depths < 50 km and epicentral distances of up to 400 km from 1996 to 2010. Using both peak ground acceleration (PGA) and peak ground velocity (PGV) we derived GMPEs in Japan. These GMPEs are used as the basis for regional magnitude determination. Predicted magnitudes from PGA values (Mpga) and predicted magnitudes from PGV values (Mpgv) were defined. Mpga and Mpgv strongly correlate with the moment magnitude of the event, provided sufficient records for each event are available. The results show that Mpgv has a smaller standard deviation in comparison to Mpga when compared with the estimated magnitudes and provides a more accurate early assessment of earthquake magnitude. We test this new method to estimate the magnitude of the 2011 Tohoku earthquake and we present the results of this estimation. PGA and PGV from borehole recordings allow us to estimate the magnitude of this event 156 s and 105 s after the earthquake onset, respectively. We demonstrate that the incorporation of borehole strong ground-motion records immediately available after the occurrence of large earthquakes significantly increases the accuracy of earthquake magnitude estimation and the associated improvement in earthquake and tsunami early warning systems performance. Moment magnitude versus predicted magnitude (Mpga and Mpgv).

  14. Developmental Dyscalculia in Adults: Beyond Numerical Magnitude Impairment.

    Science.gov (United States)

    De Visscher, Alice; Noël, Marie-Pascale; Pesenti, Mauro; Dormal, Valérie

    2017-09-01

    Numerous studies have tried to identify the core deficit of developmental dyscalculia (DD), mainly by assessing a possible deficit of the mental representation of numerical magnitude. Research in healthy adults has shown that numerosity, duration, and space share a partly common system of magnitude processing and representation. However, in DD, numerosity processing has until now received much more attention than the processing of other non-numerical magnitudes. To assess whether or not the processing of non-numerical magnitudes is impaired in DD, the performance of 15 adults with DD and 15 control participants was compared in four categorization tasks using numerosities, lengths, durations, and faces (as non-magnitude-based control stimuli). Results showed that adults with DD were impaired in processing numerosity and duration, while their performance in length and face categorization did not differ from controls' performance. Our findings support the idea of a nonsymbolic magnitude deficit in DD, affecting numerosity and duration processing but not length processing.

  15. Reinforcement Magnitude: An Evaluation of Preference and Reinforcer Efficacy

    OpenAIRE

    Trosclair-Lasserre, Nicole M; Lerman, Dorothea C; Call, Nathan A; Addison, Laura R; Kodak, Tiffany

    2008-01-01

    Consideration of reinforcer magnitude may be important for maximizing the efficacy of treatment for problem behavior. Nonetheless, relatively little is known about children's preferences for different magnitudes of social reinforcement or the extent to which preference is related to differences in reinforcer efficacy. The purpose of the current study was to evaluate the relations among reinforcer magnitude, preference, and efficacy by drawing on the procedures and results of basic experimenta...

  16. Integration and magnitude homogenization of the Egyptian earthquake catalogue

    International Nuclear Information System (INIS)

    Hussein, H.M.; Abou Elenean, K.A.; Marzouk, I.A.; Abu El-Nader, E.; Peresan, A.; Korrat, I.M.; Panza, G.F.; El-Gabry, M.N.

    2008-03-01

    The aim of the present work is to compile and update a catalogue of the instrumentally recorded earthquakes in Egypt, with uniform and homogeneous source parameters as required for the analysis of seismicity and seismic hazard assessment. This in turn requires a detailed analysis and comparison of the properties of different available sources, including the distribution of events with time, the magnitude completeness and the scaling relations between different kinds of magnitude reported by different agencies. The observational data cover the time interval 1900- 2004 and an area between 22--33.5 deg N and 25--3 6 deg. E. The linear regressions between various magnitude types have been evaluated for different magnitude ranges. Using the best linear relationship determined for each available pair of magnitudes, as well as those identified between the magnitudes and the seismic moment, we convert the different magnitude types into moment magnitudes M W , through a multi-step conversion process. Analysis of the catalogue completeness, based on the MW thus estimated, allows us to identify two different time intervals with homogeneous properties. The first one (1900- 1984) appears to be complete for M W ≥ 4.5, while the second one (1985-2004) can be considered complete for magnitudes M W ≥ 3. (author)

  17. Moment Magnitudes and Local Magnitudes for Small Earthquakes: Implications for Ground-Motion Prediction and b-values

    Science.gov (United States)

    Baltay, A.; Hanks, T. C.; Vernon, F.

    2016-12-01

    We illustrate two essential consequences of the systematic difference between moment magnitude and local magnitude for small earthquakes, illuminating the underlying earthquake physics. Moment magnitude, M 2/3 log M0, is uniformly valid for all earthquake sizes [Hanks and Kanamori, 1979]. However, the relationship between local magnitude ML and moment is itself magnitude dependent. For moderate events, 3> fmax. Just as importantly, if this relation is overlooked, prediction of large-magnitude ground motion from small earthquakes will be misguided. We also consider the effect of this magnitude scale difference on b-value. The oft-cited b-value of 1 should hold for small magnitudes, given M. Use of ML necessitates b=2/3 for the same data set; use of mixed, or unknown, magnitudes complicates the matter further. This is of particular import when estimating the rate of large earthquakes when one has limited data on their recurrence, as is the case for induced earthquakes in the central US.

  18. Magnitude Knowledge: The Common Core of Numerical Development

    Science.gov (United States)

    Siegler, Robert S.

    2016-01-01

    The integrated theory of numerical development posits that a central theme of numerical development from infancy to adulthood is progressive broadening of the types and ranges of numbers whose magnitudes are accurately represented. The process includes four overlapping trends: (1) representing increasingly precisely the magnitudes of non-symbolic…

  19. Linear Numerical-Magnitude Representations Aid Children's Memory for Numbers

    Science.gov (United States)

    Thompson, Clarissa A.; Siegler, Robert S.

    2010-01-01

    We investigated the relation between children's numerical-magnitude representations and their memory for numbers. Results of three experiments indicated that the more linear children's magnitude representations were, the more closely their memory of the numbers approximated the numbers presented. This relation was present for preschoolers and…

  20. Non extensivity and frequency magnitude distribution of earthquakes

    International Nuclear Information System (INIS)

    Sotolongo-Costa, Oscar; Posadas, Antonio

    2003-01-01

    Starting from first principles (in this case a non-extensive formulation of the maximum entropy principle) and a phenomenological approach, an explicit formula for the magnitude distribution of earthquakes is derived, which describes earthquakes in the whole range of magnitudes. The Gutenberg-Richter law appears as a particular case of the obtained formula. Comparison with geophysical data gives a very good agreement

  1. Reinforcement Magnitude: An Evaluation of Preference and Reinforcer Efficacy

    Science.gov (United States)

    Trosclair-Lasserre, Nicole M.; Lerman, Dorothea C.; Call, Nathan A.; Addison, Laura R.; Kodak, Tiffany

    2008-01-01

    Consideration of reinforcer magnitude may be important for maximizing the efficacy of treatment for problem behavior. Nonetheless, relatively little is known about children's preferences for different magnitudes of social reinforcement or the extent to which preference is related to differences in reinforcer efficacy. The purpose of the current…

  2. Adolescents with Developmental Dyscalculia Do Not Have a Generalized Magnitude Deficit – Processing of Discrete and Continuous Magnitudes

    Science.gov (United States)

    McCaskey, Ursina; von Aster, Michael; O’Gorman Tuura, Ruth; Kucian, Karin

    2017-01-01

    The link between number and space has been discussed in the literature for some time, resulting in the theory that number, space and time might be part of a generalized magnitude system. To date, several behavioral and neuroimaging findings support the notion of a generalized magnitude system, although contradictory results showing a partial overlap or separate magnitude systems are also found. The possible existence of a generalized magnitude processing area leads to the question how individuals with developmental dyscalculia (DD), known for deficits in numerical-arithmetical abilities, process magnitudes. By means of neuropsychological tests and functional magnetic resonance imaging (fMRI) we aimed to examine the relationship between number and space in typical and atypical development. Participants were 16 adolescents with DD (14.1 years) and 14 typically developing (TD) peers (13.8 years). In the fMRI paradigm participants had to perform discrete (arrays of dots) and continuous magnitude (angles) comparisons as well as a mental rotation task. In the neuropsychological tests, adolescents with dyscalculia performed significantly worse in numerical and complex visuo-spatial tasks. However, they showed similar results to TD peers when making discrete and continuous magnitude decisions during the neuropsychological tests and the fMRI paradigm. A conjunction analysis of the fMRI data revealed commonly activated higher order visual (inferior and middle occipital gyrus) and parietal (inferior and superior parietal lobe) magnitude areas for the discrete and continuous magnitude tasks. Moreover, no differences were found when contrasting both magnitude processing conditions, favoring the possibility of a generalized magnitude system. Group comparisons further revealed that dyscalculic subjects showed increased activation in domain general regions, whilst TD peers activate domain specific areas to a greater extent. In conclusion, our results point to the existence of a

  3. Adolescents with Developmental Dyscalculia Do Not Have a Generalized Magnitude Deficit - Processing of Discrete and Continuous Magnitudes.

    Science.gov (United States)

    McCaskey, Ursina; von Aster, Michael; O'Gorman Tuura, Ruth; Kucian, Karin

    2017-01-01

    The link between number and space has been discussed in the literature for some time, resulting in the theory that number, space and time might be part of a generalized magnitude system. To date, several behavioral and neuroimaging findings support the notion of a generalized magnitude system, although contradictory results showing a partial overlap or separate magnitude systems are also found. The possible existence of a generalized magnitude processing area leads to the question how individuals with developmental dyscalculia (DD), known for deficits in numerical-arithmetical abilities, process magnitudes. By means of neuropsychological tests and functional magnetic resonance imaging (fMRI) we aimed to examine the relationship between number and space in typical and atypical development. Participants were 16 adolescents with DD (14.1 years) and 14 typically developing (TD) peers (13.8 years). In the fMRI paradigm participants had to perform discrete (arrays of dots) and continuous magnitude (angles) comparisons as well as a mental rotation task. In the neuropsychological tests, adolescents with dyscalculia performed significantly worse in numerical and complex visuo-spatial tasks. However, they showed similar results to TD peers when making discrete and continuous magnitude decisions during the neuropsychological tests and the fMRI paradigm. A conjunction analysis of the fMRI data revealed commonly activated higher order visual (inferior and middle occipital gyrus) and parietal (inferior and superior parietal lobe) magnitude areas for the discrete and continuous magnitude tasks. Moreover, no differences were found when contrasting both magnitude processing conditions, favoring the possibility of a generalized magnitude system. Group comparisons further revealed that dyscalculic subjects showed increased activation in domain general regions, whilst TD peers activate domain specific areas to a greater extent. In conclusion, our results point to the existence of a

  4. Conversion of Local and Surface-Wave Magnitudes to Moment Magnitude for Earthquakes in the Chinese Mainland

    Science.gov (United States)

    Li, X.; Gao, M.

    2017-12-01

    The magnitude of an earthquake is one of its basic parameters and is a measure of its scale. It plays a significant role in seismology and earthquake engineering research, particularly in the calculations of the seismic rate and b value in earthquake prediction and seismic hazard analysis. However, several current types of magnitudes used in seismology research, such as local magnitude (ML), surface wave magnitude (MS), and body-wave magnitude (MB), have a common limitation, which is the magnitude saturation phenomenon. Fortunately, the problem of magnitude saturation was solved by a formula for calculating the seismic moment magnitude (MW) based on the seismic moment, which describes the seismic source strength. Now the moment magnitude is very commonly used in seismology research. However, in China, the earthquake scale is primarily based on local and surface-wave magnitudes. In the present work, we studied the empirical relationships between moment magnitude (MW) and local magnitude (ML) as well as surface wave magnitude (MS) in the Chinese Mainland. The China Earthquake Networks Center (CENC) ML catalog, China Seismograph Network (CSN) MS catalog, ANSS Comprehensive Earthquake Catalog (ComCat), and Global Centroid Moment Tensor (GCMT) are adopted to regress the relationships using the orthogonal regression method. The obtained relationships are as follows: MW=0.64+0.87MS; MW=1.16+0.75ML. Therefore, in China, if the moment magnitude of an earthquake is not reported by any agency in the world, we can use the equations mentioned above for converting ML to MW and MS to MW. These relationships are very important, because they will allow the China earthquake catalogs to be used more effectively for seismic hazard analysis, earthquake prediction, and other seismology research. We also computed the relationships of and (where Mo is the seismic moment) by linear regression using the Global Centroid Moment Tensor. The obtained relationships are as follows: logMo=18

  5. Defining Tsunami Magnitude as Measure of Potential Impact

    Science.gov (United States)

    Titov, V. V.; Tang, L.

    2016-12-01

    The goal of tsunami forecast, as a system for predicting potential impact of a tsunami at coastlines, requires quick estimate of a tsunami magnitude. This goal has been recognized since the beginning of tsunami research. The work of Kajiura, Soloviev, Abe, Murty, and many others discussed several scales for tsunami magnitude based on estimates of tsunami energy. However, difficulties of estimating tsunami energy based on available tsunami measurements at coastal sea-level stations has carried significant uncertainties and has been virtually impossible in real time, before tsunami impacts coastlines. The slow process of tsunami magnitude estimates, including collection of vast amount of available coastal sea-level data from affected coastlines, made it impractical to use any tsunami magnitude scales in tsunami warning operations. Uncertainties of estimates made tsunami magnitudes difficult to use as universal scale for tsunami analysis. Historically, the earthquake magnitude has been used as a proxy of tsunami impact estimates, since real-time seismic data is available of real-time processing and ample amount of seismic data is available for an elaborate post event analysis. This measure of tsunami impact carries significant uncertainties in quantitative tsunami impact estimates, since the relation between the earthquake and generated tsunami energy varies from case to case. In this work, we argue that current tsunami measurement capabilities and real-time modeling tools allow for establishing robust tsunami magnitude that will be useful for tsunami warning as a quick estimate for tsunami impact and for post-event analysis as a universal scale for tsunamis inter-comparison. We present a method for estimating the tsunami magnitude based on tsunami energy and present application of the magnitude analysis for several historical events for inter-comparison with existing methods.

  6. New moment magnitude scale, evidence of stress drop magnitude scaling and stochastic ground motion model for the French West Indies

    Science.gov (United States)

    Drouet, Stéphane; Bouin, Marie-Paule; Cotton, Fabrice

    2011-12-01

    In this study we analyse records from the 'Les Saintes' seismic sequence following the Mw= 6.3 earthquake of 2004 November 11, which occurred close to Guadeloupe (French West Indies). 485 earthquakes with magnitudes from 2 to 6, recorded at distances between 5 and 150 km are used. S-waves Fourier spectra are analysed to simultaneously determine source, path and site terms. The results show that the duration magnitude routinely estimated for the events that occurred in the region underestimate moment magnitude by 0.5 magnitude units over the whole magnitude range. From the inverted seismic moments and corner frequencies, we compute Brune's stress drops. We show that stress drops increase with increasing magnitude. The same pattern is observed on apparent stresses (i.e. the seismic energy-to-moment ratio). However, the rate of increase diminishes at high magnitudes, which is consistent with a constant stress drop model for large events. Using the results of the inversions, we perform ground motion simulations for the entire data set using the SMSIM stochastic simulation tool. The results show that a good fit (σ= 0.25) with observed data is achieved when the source is properly described by its moment magnitude and stress drop, and when site effects are taken into account. Although the magnitude-dependent stress drop model is giving better results than the constant stress drop model, the interevent variability remains high, which could suggest that stress drop depends on other parameters such as the depth of the hypocentre. In any case, the overall variability is of the same order of magnitude as usually observed in empirical ground motion prediction equations.

  7. Characteristics of North Korea nuclear test and KMA magnitude scale

    Science.gov (United States)

    Jeon, Y. S.; Lee, D.; Min, K.; Hwang, E. H.; Lee, J.; Park, E.; Jo, E.; Lee, M. S.

    2017-12-01

    Democratic People's Republic of Korea(DPRK) carried out 6th nuclear test on 3 Sep. 2017 at 03:30 UTC. Korea Meteorological Administration(KMA) announced to the public that the event took place in the DPRK's test site, Punggye-ri with the magnitude 5.7. This event is larger than previous one in terms of magnitude and showed that measured magnitude strongly depends on the frequency band of data. After we applied several magnitude scales such as Everdon(1967), Nuttli(1967), and Hong & Lee(2012) to this event, we found that magnitude ranges from 5.3 to 6.7 which depends on frequency band and epicentral distance of signal. 6th DPRK test experiment indicated that spectral amplitude ratio of 6th/5th near 2.37 Hz shows similar amplification compatible to relative spectral magnitude 5.7, while spectral amplitude ratio of 6th/5th near 1.0 Hz marks relative spectral magnitude about 6.1. Relative spectral magnitude varies with frequencies and decreases as frequency increase. We found that systematic non-linearity exists for spectral amplitude ratio of 6th/5th from 1.0 to 10.0 Hz, while it's characteristic is not found at 5th/4th and 4th/3th. A methodology is presented for determining mb(Pn) magnitude of underground nuclear explosions from local Pn phase. 582 waveforms from vertical component of broadband and acceleration seismographs at 120 stations in the epicenter distance from 340 to 800 km are used to calibrate mb(Pn) magnitude scaling for DPRK's nuclear tests. The mb(Pn) estimates of regional events for Korean Peninsula are determined to be mb(Pn) ? = log10(A) + 2.1164×log10(d) - 0.2721, where A is the peak-to-peak Pn amplitude in μm and d is the epicentral distance in km. Systematic non-linearity does not observed at frequency band from 0.1 to 1.0 Hz. The magnitude of 6th event is mb(Pn) 6.08 and mb(Pn) 4.52, 4.92, 4.84 and 5.03 for 2nd, 3rd, 4th and 5th respectively. Further research of applicable mb(Pn) magnitude scaling is required for all frequency band and

  8. The bolometric, infrared and visual absolute magnitudes of Mira variables

    International Nuclear Information System (INIS)

    Robertson, B.S.C.; Feast, M.W.

    1981-01-01

    Statistical parallaxes, as well as stars with individually known distances are used to derive bolometric and infrared absolute magnitudes of Mira (Me) variables. The derived bolometric magnitudes are in the mean about 0.75 mag fainter than recent estimates. The problem of determining the pulsation constant is discussed. Miras with periods greater than 150 days probably pulsate in the first overtone. Those of shorter periods are anomalous and may be fundamental pulsators. It is shown that the absolute visual magnitudes at mean light of Miras with individually determined distances are consistent with values derived by Clayton and Feast from statistical parallaxes. (author)

  9. On the magnitude and recurence of Vrancea earthquakes

    International Nuclear Information System (INIS)

    Oncescu, M.C.

    1987-07-01

    The moment-magnitude scale Msub(W) is proposed for the quantification of Vrancea earthquakes. The asperity model is found adequate to explain the observed quasi-cycles and super-cycles in the occurrence of large events. (auhtor)

  10. Disparities in the Magnitude of Human Immunodeficiency Virus ...

    African Journals Online (AJOL)

    and low/middle‑income countries (LMICs) in the magnitude of HIV‑related OIs in pre‑highly ... HICs while tuberculosis, candidiasis, chronic diarrhea, and cryptococcosis were predominant ...... Mohar A. Transfusion associated AIDS in Mexico.

  11. Magnitude and factors associated with post-cesarean surgical site ...

    African Journals Online (AJOL)

    Magnitude and factors associated with post-cesarean surgical site infection at Hawassa University Teaching and referral hospital, southern Ethiopia: a ... the hospital. Thus, it should be averted by implementing infection prevention techniques.

  12. Rapid earthquake magnitude determination for Vrancea early warning system

    International Nuclear Information System (INIS)

    Marmureanu, Alexandru

    2009-01-01

    Due to the huge amount of recorded data, an automatic procedure was developed and used to test different methods to rapidly evaluate earthquake magnitude from the first seconds of the P wave. In order to test all the algorithms involved in detection and rapid earthquake magnitude estimation, several tests were performed, in order to avoid false alarms. A special detection algorithm was developed, that is based on the classical STA/LTA algorithm and tuned for early warning purpose. A method to rapidly estimate magnitude in 4 seconds from detection of P wave in the epicenter is proposed. The method was tested on al recorded data, and the magnitude error determination is acceptable taking into account that it is computed from only 3 stations in a very short time interval. (author)

  13. Impact of magnitude uncertainties on seismic catalogue properties

    Science.gov (United States)

    Leptokaropoulos, K. M.; Adamaki, A. K.; Roberts, R. G.; Gkarlaouni, C. G.; Paradisopoulou, P. M.

    2018-05-01

    Catalogue-based studies are of central importance in seismological research, to investigate the temporal, spatial and size distribution of earthquakes in specified study areas. Methods for estimating the fundamental catalogue parameters like the Gutenberg-Richter (G-R) b-value and the completeness magnitude (Mc) are well established and routinely applied. However, the magnitudes reported in seismicity catalogues contain measurement uncertainties which may significantly distort the estimation of the derived parameters. In this study, we use numerical simulations of synthetic data sets to assess the reliability of different methods for determining b-value and Mc, assuming the G-R law validity. After contaminating the synthetic catalogues with Gaussian noise (with selected standard deviations), the analysis is performed for numerous data sets of different sample size (N). The noise introduced to the data generally leads to a systematic overestimation of magnitudes close to and above Mc. This fact causes an increase of the average number of events above Mc, which in turn leads to an apparent decrease of the b-value. This may result to a significant overestimation of seismicity rate even well above the actual completeness level. The b-value can in general be reliably estimated even for relatively small data sets (N < 1000) when only magnitudes higher than the actual completeness level are used. Nevertheless, a correction of the total number of events belonging in each magnitude class (i.e. 0.1 unit) should be considered, to deal with the magnitude uncertainty effect. Because magnitude uncertainties (here with the form of Gaussian noise) are inevitable in all instrumental catalogues, this finding is fundamental for seismicity rate and seismic hazard assessment analyses. Also important is that for some data analyses significant bias cannot necessarily be avoided by choosing a high Mc value for analysis. In such cases, there may be a risk of severe miscalculation of

  14. Rapid Moment Magnitude Estimation Using Strong Motion Derived Static Displacements

    OpenAIRE

    Muzli, Muzli; Asch, Guenter; Saul, Joachim; Murjaya, Jaya

    2015-01-01

    The static surface deformation can be recovered from strong motion records. Compared to satellite-based measurements such as GPS or InSAR, the advantage of strong motion records is that they have the potential to provide real-time coseismic static displacements. The use of these valuable data was optimized for the moment magnitude estimation. A centroid grid search method was introduced to calculate the moment magnitude by using1 model. The method to data sets was applied of the 2011...

  15. The magnitude of innovation and its evolution in social animals.

    Science.gov (United States)

    Arbilly, Michal; Laland, Kevin N

    2017-02-08

    Innovative behaviour in animals, ranging from invertebrates to humans, is increasingly recognized as an important topic for investigation by behavioural researchers. However, what constitutes an innovation remains controversial, and difficult to quantify. Drawing on a broad definition whereby any behaviour with a new component to it is an innovation, we propose a quantitative measure, which we call the magnitude of innovation , to describe the extent to which an innovative behaviour is novel. This allows us to distinguish between innovations that are a slight change to existing behaviours (low magnitude), and innovations that are substantially different (high magnitude). Using mathematical modelling and evolutionary computer simulations, we explored how aspects of social interaction, cognition and natural selection affect the frequency and magnitude of innovation. We show that high-magnitude innovations are likely to arise regularly even if the frequency of innovation is low, as long as this frequency is relatively constant, and that the selectivity of social learning and the existence of social rewards, such as prestige and royalties, are crucial for innovative behaviour to evolve. We suggest that consideration of the magnitude of innovation may prove a useful tool in the study of the evolution of cognition and of culture. © 2017 The Author(s).

  16. Iranian earthquakes, a uniform catalog with moment magnitudes

    Science.gov (United States)

    Karimiparidari, Sepideh; Zaré, Mehdi; Memarian, Hossein; Kijko, Andrzej

    2013-07-01

    A uniform earthquake catalog is an essential tool in any seismic hazard analysis. In this study, an earthquake catalog of Iran and adjacent areas was compiled, using international and national databanks. The following priorities were applied in selecting magnitude and earthquake location: (a) local catalogs were given higher priority for establishing the location of an earthquake and (b) global catalogs were preferred for determining earthquake magnitudes. Earthquakes that have occurred within the bounds between 23-42° N and 42-65° E, with a magnitude range of M W 3.5-7.9, from the third millennium BC until April 2010 were included. In an effort to avoid the "boundary effect," since the newly compiled catalog will be mainly used for seismic hazard assessment, the study area includes the areas adjacent to Iran. The standardization of the catalog in terms of magnitude was achieved by the conversion of all types of magnitude into moment magnitude, M W, by using the orthogonal regression technique. In the newly compiled catalog, all aftershocks were detected, based on the procedure described by Gardner and Knopoff (Bull Seismol Soc Am 64:1363-1367, 1974). The seismicity parameters were calculated for the six main tectonic seismic zones of Iran, i.e., the Zagros Mountain Range, the Alborz Mountain Range, Central Iran, Kope Dagh, Azerbaijan, and Makran.

  17. Changes in the timing and magnitude of floods in Canada

    International Nuclear Information System (INIS)

    Cunderlik, J.M.; Ouarda, T.B.M.J.

    2008-01-01

    It is expected that the global climate change will have significant impacts on the regime of hydrologic extremes. An increase in both the frequency and magnitude of hydrologic extremes is anticipated in the near future. As a consequence, the design and operation of water resource systems will have to adapt to the changing regime of hydrologic extremes. This study explores trends in the timing and magnitude of floods in natural streamflow gauging stations in Canada. The seasonality of floods is analyzed and the selected streamflow stations grouped into five flood seasonality regions. A common 30-year long observation period from 1974 to 2003 is used in the analysis to eliminate the effect of hydro-climatic variability in the timing and magnitude of floods resulting from different observation periods. The timing of floods is described in terms of directional statistics. A method is developed for analyzing trends in directional dates of flood occurrence that is not affected by the choice of zero direction. The magnitude of floods is analyzed by the annual maximum and peak-over-threshold methods. Trends in the timing and magnitude of floods are identified in each flood seasonality region using the Mann-Kendall nonparametric test, with a modification for auto-correlated data. The results show a good correspondence between the identified flood seasonality regions and the main terrestrial zones in Canada. Significant changes in the timing and magnitude of floods are found in the flood seasonality regions. (author)

  18. Estimation of the Magnitude of Excavation Damaged Zone at KURT

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Won Jin; Kim, Jin Sub; Lee, Changsoo; Cho, Heui Joo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    In the EDZ, the permeability of the rock increases. The annular EDZ surrounding the tunnel may act as a continuous and high-permeable pathway for the groundwater flow, which accelerates the intrusion of groundwater into the repository and increases the release of radionuclide into the biosphere from the repository. Therefore an investigation on the magnitude of the EDZ has been important from the viewpoint of mechanical stability and radiological safety for a geological repository. In this study, two in-situ measurements were performed at the KURT (KAERI Underground Research Tunnel) to investigate the magnitude of the EDZ. The magnitude of EDZ was estimated to be 0.6 to 1.8 m from the tunnel wall on the basis of the deformation modulus, and the value of deformation modulus in the EDZ is about 40% of those in undisturbed zone. The magnitude of EDZ can be estimated to be about 2 m from the viewpoint of permeability, and the permeabilities in the EDZ seem to be increased at up to 2 orders of magnitude compared with those in the intact rock. The magnitude of EDZ estimated based on the permeability is larger than that from the Goodman jack test.

  19. Probable Maximum Earthquake Magnitudes for the Cascadia Subduction

    Science.gov (United States)

    Rong, Y.; Jackson, D. D.; Magistrale, H.; Goldfinger, C.

    2013-12-01

    The concept of maximum earthquake magnitude (mx) is widely used in seismic hazard and risk analysis. However, absolute mx lacks a precise definition and cannot be determined from a finite earthquake history. The surprising magnitudes of the 2004 Sumatra and the 2011 Tohoku earthquakes showed that most methods for estimating mx underestimate the true maximum if it exists. Thus, we introduced the alternate concept of mp(T), probable maximum magnitude within a time interval T. The mp(T) can be solved using theoretical magnitude-frequency distributions such as Tapered Gutenberg-Richter (TGR) distribution. The two TGR parameters, β-value (which equals 2/3 b-value in the GR distribution) and corner magnitude (mc), can be obtained by applying maximum likelihood method to earthquake catalogs with additional constraint from tectonic moment rate. Here, we integrate the paleoseismic data in the Cascadia subduction zone to estimate mp. The Cascadia subduction zone has been seismically quiescent since at least 1900. Fortunately, turbidite studies have unearthed a 10,000 year record of great earthquakes along the subduction zone. We thoroughly investigate the earthquake magnitude-frequency distribution of the region by combining instrumental and paleoseismic data, and using the tectonic moment rate information. To use the paleoseismic data, we first estimate event magnitudes, which we achieve by using the time interval between events, rupture extent of the events, and turbidite thickness. We estimate three sets of TGR parameters: for the first two sets, we consider a geographically large Cascadia region that includes the subduction zone, and the Explorer, Juan de Fuca, and Gorda plates; for the third set, we consider a narrow geographic region straddling the subduction zone. In the first set, the β-value is derived using the GCMT catalog. In the second and third sets, the β-value is derived using both the GCMT and paleoseismic data. Next, we calculate the corresponding mc

  20. What controls the maximum magnitude of injection-induced earthquakes?

    Science.gov (United States)

    Eaton, D. W. S.

    2017-12-01

    Three different approaches for estimation of maximum magnitude are considered here, along with their implications for managing risk. The first approach is based on a deterministic limit for seismic moment proposed by McGarr (1976), which was originally designed for application to mining-induced seismicity. This approach has since been reformulated for earthquakes induced by fluid injection (McGarr, 2014). In essence, this method assumes that the upper limit for seismic moment release is constrained by the pressure-induced stress change. A deterministic limit is given by the product of shear modulus and the net injected fluid volume. This method is based on the assumptions that the medium is fully saturated and in a state of incipient failure. An alternative geometrical approach was proposed by Shapiro et al. (2011), who postulated that the rupture area for an induced earthquake falls entirely within the stimulated volume. This assumption reduces the maximum-magnitude problem to one of estimating the largest potential slip surface area within a given stimulated volume. Finally, van der Elst et al. (2016) proposed that the maximum observed magnitude, statistically speaking, is the expected maximum value for a finite sample drawn from an unbounded Gutenberg-Richter distribution. These three models imply different approaches for risk management. The deterministic method proposed by McGarr (2014) implies that a ceiling on the maximum magnitude can be imposed by limiting the net injected volume, whereas the approach developed by Shapiro et al. (2011) implies that the time-dependent maximum magnitude is governed by the spatial size of the microseismic event cloud. Finally, the sample-size hypothesis of Van der Elst et al. (2016) implies that the best available estimate of the maximum magnitude is based upon observed seismicity rate. The latter two approaches suggest that real-time monitoring is essential for effective management of risk. A reliable estimate of maximum

  1. The Strain Energy, Seismic Moment and Magnitudes of Large Earthquakes

    Science.gov (United States)

    Purcaru, G.

    2004-12-01

    The strain energy Est, as potential energy, released by an earthquake and the seismic moment Mo are two fundamental physical earthquake parameters. The earthquake rupture process ``represents'' the release of the accumulated Est. The moment Mo, first obtained in 1966 by Aki, revolutioned the quantification of earthquake size and led to the elimination of the limitations of the conventional magnitudes (originally ML, Richter, 1930) mb, Ms, m, MGR. Both Mo and Est, not in a 1-to-1 correspondence, are uniform measures of the size, although Est is presently less accurate than Mo. Est is partitioned in seismic- (Es), fracture- (Eg) and frictional-energy Ef, and Ef is lost as frictional heat energy. The available Est = Es + Eg (Aki and Richards (1980), Kostrov and Das, (1988) for fundamentals on Mo and Est). Related to Mo, Est and Es, several modern magnitudes were defined under various assumptions: the moment magnitude Mw (Kanamori, 1977), strain energy magnitude ME (Purcaru and Berckhemer, 1978), tsunami magnitude Mt (Abe, 1979), mantle magnitude Mm (Okal and Talandier, 1987), seismic energy magnitude Me (Choy and Boatright, 1995, Yanovskaya et al, 1996), body-wave magnitude Mpw (Tsuboi et al, 1998). The available Est = (1/2μ )Δ σ Mo, Δ σ ~=~average stress drop, and ME is % \\[M_E = 2/3(\\log M_o + \\log(\\Delta\\sigma/\\mu)-12.1) ,\\] % and log Est = 11.8 + 1.5 ME. The estimation of Est was modified to include Mo, Δ and μ of predominant high slip zones (asperities) to account for multiple events (Purcaru, 1997): % \\[E_{st} = \\frac{1}{2} \\sum_i {\\frac{1}{\\mu_i} M_{o,i} \\Delta\\sigma_i} , \\sum_i M_{o,i} = M_o \\] % We derived the energy balance of Est, Es and Eg as: % \\[ E_{st}/M_o = (1+e(g,s)) E_s/M_o , e(g,s) = E_g/E_s \\] % We analyzed a set of about 90 large earthquakes and found that, depending on the goal these magnitudes quantify differently the rupture process, thus providing complementary means of earthquake characterization. Results for some

  2. Magnitude corrections for attenuation in the upper mantle

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    Since 1969, a consistent discrepancy in seismic magnitudes of nuclear detonations at NTS compared with magnitudes of detonations elsewhere in the world has been observed. This discrepancy can be explained in terms of a relatively high seismic attenuation for compressional waves in the upper mantle beneath the NTS and in certain other locations. A correction has been developed for this attenuation based on a relationship between the velocity of compressional waves at the top of the earth's mantle (just beneath the Mohorovicic discontinuity) and the seismic attenuation further down in the upper mantle. Our new definition of body-wave magnitude includes corrections for attenuation in the upper mantle at both ends of the teleseismic body-wave path. These corrections bring the NTS oservations into line with measurements of foreign events, and enable one to make more reliable estimates of yields of underground nuclear explosions, wherever the explosion occurs

  3. Magnitude and duration of stretch modulate fibroblast remodeling.

    Science.gov (United States)

    Balestrini, Jenna L; Billiar, Kristen L

    2009-05-01

    Mechanical cues modulate fibroblast tractional forces and remodeling of extracellular matrix in healthy tissue, healing wounds, and engineered matrices. The goal of the present study is to establish dose-response relationships between stretch parameters (magnitude and duration per day) and matrix remodeling metrics (compaction, strength, extensibility, collagen content, contraction, and cellularity). Cyclic equibiaxial stretch of 2-16% was applied to fibroblast-populated fibrin gels for either 6 h or 24 h/day for 8 days. Trends in matrix remodeling metrics as a function of stretch magnitude and duration were analyzed using regression analysis. The compaction and ultimate tensile strength of the tissues increased in a dose-dependent manner with increasing stretch magnitude, yet remained unaffected by the duration in which they were cycled (6 h/day versus 24 h/day). Collagen density increased exponentially as a function of both the magnitude and duration of stretch, with samples stretched for the reduced duration per day having the highest levels of collagen accumulation. Cell number and failure tension were also dependent on both the magnitude and duration of stretch, although stretch-induced increases in these metrics were only present in the samples loaded for 6 h/day. Our results indicate that both the magnitude and the duration per day of stretch are critical parameters in modulating fibroblast remodeling of the extracellular matrix, and that these two factors regulate different aspects of this remodeling. These findings move us one step closer to fully characterizing culture conditions for tissue equivalents, developing improved wound healing treatments and understanding tissue responses to changes in mechanical environments during growth, repair, and disease states.

  4. Color-magnitude relations in nearby galaxy clusters

    Science.gov (United States)

    Rasheed, Mariwan A.; Mohammad, Khalid K.

    2018-06-01

    The rest-frame (g-r) /Mr color-magnitude relations of 12 Abell-type clusters are analyzed in the redshift range (0.02≲ z ≲ 0.10) and within a projected radius of 0.75 Mpc using photometric data from SDSS-DR9. We show that the color-magnitude relation parameters (slope, zero-point, and scatter) do not exhibit significant evolution within this low-redshift range. Thus, we can say that during the look-back time of z ˜ 0.1 all red sequence galaxies evolve passively, without any star formation activity.

  5. High-magnitude head impact exposure in youth football

    Science.gov (United States)

    Campolettano, Eamon T.; Gellner, Ryan A.; Rowson, Steven

    2018-01-01

    OBJECTIVE Even in the absence of a clinically diagnosed concussion, research suggests that neurocognitive changes may develop in football players as a result of frequent head impacts that occur during football games and practices. The objectives of this study were to determine the specific situations in which high-magnitude impacts (accelerations exceeding 40g) occur in youth football games and practices and to assess how representative practice activities are of games with regard to high-magnitude head impact exposure. METHODS A total of 45 players (mean age 10.7 ± 1.1 years) on 2 youth teams (Juniors [mean age 9.9 ± 0.6 years; mean body mass 38.9 ± 9.9 kg] and Seniors [mean age 11.9 ± 0.6 years; mean body mass 51.4 ± 11.8 kg]) wore helmets instrumented with accelerometer arrays to record head impact accelerations for all practices and games. Video recordings from practices and games were used to verify all high-magnitude head impacts, identify specific impact characteristics, and determine the amount of time spent in each activity. RESULTS A total of 7590 impacts were recorded, of which 571 resulted in high-magnitude head impact accelerations exceeding 40g (8%). Impacts were characterized based on the position played by the team member who received the impact, the part of the field where the impact occurred, whether the impact occurred during a game or practice play, and the cause of the impact. High-magnitude impacts occurred most frequently in the open field in both games (59.4%) and practices (67.5%). “Back” position players experienced a greater proportion of high-magnitude head impacts than players at other positions. The 2 teams in this study structured their practice sessions similarly with respect to time spent in each drill, but impact rates differed for each drill between the teams. CONCLUSIONS High-magnitude head impact exposure in games and practice drills was quantified and used as the basis for comparison of exposure in the 2 settings. In

  6. Image reconstruction from pairs of Fourier-transform magnitude

    International Nuclear Information System (INIS)

    Hunt, B.R.; Overman, T.L.; Gough, P.

    1998-01-01

    The retrieval of phase information from only the magnitude of the Fourier transform of a signal remains an important problem for many applications. We present an algorithm for phase retrieval when there exist two related sets of Fourier-transform magnitude data. The data are assumed to come from a single object observed in two different polarizations through a distorting medium, so the phase component of the Fourier transform of the object is corrupted. Phase retrieval is accomplished by minimization of a suitable criterion function, which can take three different forms. copyright 1998 Optical Society of America

  7. Improving Children's Knowledge of Fraction Magnitudes

    Science.gov (United States)

    Fazio, Lisa K.; Kennedy, Casey A.; Siegler, Robert S.

    2016-01-01

    We examined whether playing a computerized fraction game, based on the integrated theory of numerical development and on the Common Core State Standards' suggestions for teaching fractions, would improve children's fraction magnitude understanding. Fourth and fifth-graders were given brief instruction about unit fractions and played "Catch…

  8. Lower bound earthquake magnitude for probabilistic seismic hazard evaluation

    International Nuclear Information System (INIS)

    McCann, M.W. Jr.; Reed, J.W.

    1990-01-01

    This paper presents the results of a study that develops an engineering and seismological basis for selecting a lower-bound magnitude (LBM) for use in seismic hazard assessment. As part of a seismic hazard analysis the range of earthquake magnitudes that are included in the assessment of the probability of exceedance of ground motion must be defined. The upper-bound magnitude is established by earth science experts based on their interpretation of the maximum size of earthquakes that can be generated by a seismic source. The lower-bound or smallest earthquake that is considered in the analysis must also be specified. The LBM limits the earthquakes that are considered in assessing the probability that specified ground motion levels are exceeded. In the past there has not been a direct consideration of the appropriate LBM value that should be used in a seismic hazard assessment. This study specifically looks at the selection of a LBM for use in seismic hazard analyses that are input to the evaluation/design of nuclear power plants (NPPs). Topics addressed in the evaluation of a LBM are earthquake experience data at heavy industrial facilities, engineering characteristics of ground motions associated with small-magnitude earthquakes, probabilistic seismic risk assessments (seismic PRAs), and seismic margin evaluations. The results of this study and the recommendations concerning a LBM for use in seismic hazard assessments are discussed. (orig.)

  9. Magnitude of stress and academic achievement of female students ...

    African Journals Online (AJOL)

    Stress is a universal phenomenon which no human being is free from. This paper examined the magnitude of stress and academic achievement of female students of the University of Ilorin. It was a description survey type. The target population comprised the 400 level female students from the four randomly selected ...

  10. Sequential sampling, magnitude estimation, and the wisdom of crowds

    DEFF Research Database (Denmark)

    Nash, Ulrik W.

    2017-01-01

    in the wisdom of crowds indicated by judgment distribution skewness. The present study reports findings from an experiment on magnitude estimation and supports these predictions. The study moreover demonstrates that systematic errors by groups of people can be corrected using information about the judgment...

  11. A catalog of observed nuclear magnitudes of Jupiter family comets

    Science.gov (United States)

    Tancredi, G.; Fernández, J. A.; Rickman, H.; Licandro, J.

    2000-10-01

    A catalog of a sample of 105 Jupiter family (JF) comets (defined as those with Tisserand constants T > 2 and orbital periods P International Comet Quarterly Archive of Cometary Photometric Data, the Minor Planet Center (MPC) data base, IAU Circulars, International Comet Quarterly, and a few papers devoted to some particular comets, together with our own observations. Photometric data previous to 1990 have mainly been taken from the Comet Light Curve Catalogue (CLICC) compiled by Kamél (\\cite{kamel}). We discuss the reliability of the reported nuclear magnitudes in relation to the inherent sources of errors and uncertainties, in particular the coma contamination often present even at large heliocentric distances. A large fraction of the JF comets of our sample indeed shows various degrees of activity at large heliocentric distances, which is correlated with recent downward jumps in their perihelion distances. The reliability of coma subtraction methods to compute the nuclear magnitude is also discussed. Most absolute nuclear magnitudes are found in the range 15 - 18, with no magnitudes fainter than H_N ~ 19.5. The catalog can be found at: http://www.fisica.edu.uy/ ~ gonzalo/catalog/. Table 2 and Appendix B are only available in electronic form at http://www.edpsciences.org Table 5 is also available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html

  12. Magnitude and predictors of excessive alcohol use in Ethiopia ...

    African Journals Online (AJOL)

    user

    11Harvard T.H. Chan School of Public Health, Harvard University, E-mail: ST: solomon.teferra@gmail.com USA. Magnitude ..... cigarettes while drinking (34). ... Addiction. 2011;106(10):. 1718–24. 3. Alcohol an Obstacle to Development in East.

  13. The Magnitude of Obesity and its Relationship to Blood Pressure ...

    African Journals Online (AJOL)

    Background: Obesity in developing nations is no longer as uncommon as it was thought to be decades ago however paucity of data on the burden of obesity from urban communities was observed by previous workers. Aim: To determine the magnitude of obesity and its relationship to blood pressure among urban adult ...

  14. Magnitude and gender distribution of obesity and abdominal ...

    African Journals Online (AJOL)

    Background: Obesity and abdominal adiposity are associated with increased cardiovascular morbidity in diabetes. This study evaluated their magnitude and gender distribution in Nigerians with Type 2 DM attending a tertiary care clinic. Patients and Methods: 258 consecutive patients with type 2 DM were evaluated.

  15. Extremal Regions Detection Guided by Maxima of Gradient Magnitude

    DEFF Research Database (Denmark)

    Faraji, Mehdi; Shambezadeh, Jamshid; Nasrollahi, Kamal

    2015-01-01

    boundaries we introduce Maxima of Gradient Magnitudes (MGMs) which are shown to be points that are mostly around the boundaries of the regions. Having found the MGMs, the method obtains a Global Criterion (GC) for each level of the input image which is used to find Extremum Levels (ELs). The found ELs...

  16. Magnitude and correlates of moderate to severe anemia among ...

    African Journals Online (AJOL)

    Introduction: Moderate to severe anemia is an important clinical problem in HIV patients on Highly Active Antiretroviral Therapy. The rate of progression and mortality in this sub group of patients is high compared to non anemic patients. In sub Saharan Africa with scale up of Anti retroviral therapy, the magnitude of this ...

  17. The magnitude-redshift relation in a perturbed Friedmann universe

    International Nuclear Information System (INIS)

    Sasaki, Misao.

    1987-02-01

    A general formula for the magnitude-redshift relation in a linearly perturbed Friedmann universe is derived. The formula does not assume any specific gauge condition, but the gauge-invariance of it is explicitly shown. Then the application of the formula to the spatially flat background model is considered and the implications are discussed. (author)

  18. Determining on-fault earthquake magnitude distributions from integer programming

    Science.gov (United States)

    Geist, Eric L.; Parsons, Thomas E.

    2018-01-01

    Earthquake magnitude distributions among faults within a fault system are determined from regional seismicity and fault slip rates using binary integer programming. A synthetic earthquake catalog (i.e., list of randomly sampled magnitudes) that spans millennia is first formed, assuming that regional seismicity follows a Gutenberg-Richter relation. Each earthquake in the synthetic catalog can occur on any fault and at any location. The objective is to minimize misfits in the target slip rate for each fault, where slip for each earthquake is scaled from its magnitude. The decision vector consists of binary variables indicating which locations are optimal among all possibilities. Uncertainty estimates in fault slip rates provide explicit upper and lower bounding constraints to the problem. An implicit constraint is that an earthquake can only be located on a fault if it is long enough to contain that earthquake. A general mixed-integer programming solver, consisting of a number of different algorithms, is used to determine the optimal decision vector. A case study is presented for the State of California, where a 4 kyr synthetic earthquake catalog is created and faults with slip ≥3 mm/yr are considered, resulting in >106  variables. The optimal magnitude distributions for each of the faults in the system span a rich diversity of shapes, ranging from characteristic to power-law distributions. 

  19. Working Memory Strategies during Rational Number Magnitude Processing

    Science.gov (United States)

    Hurst, Michelle; Cordes, Sara

    2017-01-01

    Rational number understanding is a critical building block for success in more advanced mathematics; however, how rational number magnitudes are conceptualized is not fully understood. In the current study, we used a dual-task working memory (WM) interference paradigm to investigate the dominant type of strategy (i.e., requiring verbal WM…

  20. Estimating the magnitude of food waste generated in South Africa

    CSIR Research Space (South Africa)

    Oelofse, Suzanna HH

    2012-08-01

    Full Text Available Throughout the developed world, food is treated as a disposable commodity. Between one third and half of all food produced for human consumption globally is estimated to be wasted. However, attempts to quantify the actual magnitude of food wasted...

  1. Temporal Order Judgment Reveals How Number Magnitude Affects Visuospatial Attention

    Science.gov (United States)

    Casarotti, Marco; Michielin, Marika; Zorzi, Marco; Umilta, Carlo

    2007-01-01

    The existence of spatial components in the mental representation of number magnitude has raised the question regarding the relation between numbers and spatial attention. We present six experiments in which this relation was examined using a temporal order judgment task to index attentional allocation. Results demonstrate that one important…

  2. Analytical review of the magnitude and causes maternal death at ...

    African Journals Online (AJOL)

    Background: Tanzania is one of the countries with the highest maternal mortalities in the word and sub Saharan Africa. However, recently there have been reports of a downward trend of this tragedy in Tanzania. Objectives: This study was done to determine the magnitude and the causes of maternal deaths at Dodoma ...

  3. Representation of numerical magnitude in math-anxious individuals.

    Science.gov (United States)

    Colomé, Àngels

    2018-01-01

    Larger distance effects in high math-anxious individuals (HMA) performing comparison tasks have previously been interpreted as indicating less precise magnitude representation in this population. A recent study by Dietrich, Huber, Moeller, and Klein limited the effects of math anxiety to symbolic comparison, in which they found larger distance effects for HMA, despite equivalent size effects. However, the question of whether distance effects in symbolic comparison reflect the properties of the magnitude representation or decisional processes is currently under debate. This study was designed to further explore the relation between math anxiety and magnitude representation through three different tasks. HMA and low math-anxious individuals (LMA) performed a non-symbolic comparison, in which no group differences were found. Furthermore, we did not replicate previous findings in an Arabic digit comparison, in which HMA individuals showed equivalent distance effects to their LMA peers. Lastly, there were no group differences in a counting Stroop task. Altogether, an explanation of math anxiety differences in terms of less precise magnitude representation is not supported.

  4. Strategy Use and Strategy Choice in Fraction Magnitude Comparison

    Science.gov (United States)

    Fazio, Lisa K.; DeWolf, Melissa; Siegler, Robert S.

    2016-01-01

    We examined, on a trial-by-trial basis, fraction magnitude comparison strategies of adults with more and less mathematical knowledge. College students with high mathematical proficiency used a large variety of strategies that were well tailored to the characteristics of the problems and that were guaranteed to yield correct performance if executed…

  5. Passive seismic monitoring at the ketzin CCS site -Magnitude estimation

    NARCIS (Netherlands)

    Paap, B.F.; Steeghs, T.P.H.

    2014-01-01

    In order to allow quantification of the strength of local micro-seismic events recorded at the CCS pilot site in Ketzin in terms of local magnitude, earthquake data recorded by standardized seismometers were used. Earthquakes were selected that occurred in Poland and Czech Republic and that were

  6. The colour-magnitude diagram of NGC 5053

    International Nuclear Information System (INIS)

    Walker, M.F.; Pike, C.D.; McGee, J.D.

    1976-01-01

    The colour-magnitude diagram of NGC 5053 has been derived to V = 21.1 from photographic and electronographic observations. The electronographic observations were obtained with an experimental Spectracon image-converter, having photocathode and exit window dimensions of 20 x 30 mm, mounted at the prime-focus of the 120-in. Lick reflector. The photographic observations were obtained with the 20-in. Carnegie astrograph and the 36-in. Crossley reflector. The colour-magnitude diagram resembles that of M92, with the difference that a red horizontal branch is more pronounced than the asymptotic branch in NGC 5053. The topology of the horizontal branch is that of clusters with an intermediate metal content and is thus at variance with the mean period of the RR Lyr stars and the unreddened colour of the subgiant branch read at the magnitude level of the horizontal branch, both of which would indicate an extremely low metal content. If comparison of the colour-magnitude diagrams of NGC 5053 and M92 is valid, then the reddening of NGC 5053 is Esub(B-V) = 0.02 and the apparent distance modulus is m-M = 16.08 +- 0.08. (author)

  7. Magnitude, precision, and realism of depth perception in stereoscopic vision.

    Science.gov (United States)

    Hibbard, Paul B; Haines, Alice E; Hornsey, Rebecca L

    2017-01-01

    Our perception of depth is substantially enhanced by the fact that we have binocular vision. This provides us with more precise and accurate estimates of depth and an improved qualitative appreciation of the three-dimensional (3D) shapes and positions of objects. We assessed the link between these quantitative and qualitative aspects of 3D vision. Specifically, we wished to determine whether the realism of apparent depth from binocular cues is associated with the magnitude or precision of perceived depth and the degree of binocular fusion. We presented participants with stereograms containing randomly positioned circles and measured how the magnitude, realism, and precision of depth perception varied with the size of the disparities presented. We found that as the size of the disparity increased, the magnitude of perceived depth increased, while the precision with which observers could make depth discrimination judgments decreased. Beyond an initial increase, depth realism decreased with increasing disparity magnitude. This decrease occurred well below the disparity limit required to ensure comfortable viewing.

  8. Magnitude and predictors of excessive alcohol use in Ethiopia ...

    African Journals Online (AJOL)

    Magnitude and predictors of excessive alcohol use in Ethiopia: Findings from the 2015 national non-communicable diseases STEPS survey. ... overall prevalence of lifetime alcohol consumption was 49.3%, and 40.7% of the study participants reported consumption of alcohol in the past 30 days, defined as current drinkers.

  9. Individual Movement Variability Magnitudes Are Explained by Cortical Neural Variability.

    Science.gov (United States)

    Haar, Shlomi; Donchin, Opher; Dinstein, Ilan

    2017-09-13

    Humans exhibit considerable motor variability even across trivial reaching movements. This variability can be separated into specific kinematic components such as extent and direction that are thought to be governed by distinct neural processes. Here, we report that individual subjects (males and females) exhibit different magnitudes of kinematic variability, which are consistent (within individual) across movements to different targets and regardless of which arm (right or left) was used to perform the movements. Simultaneous fMRI recordings revealed that the same subjects also exhibited different magnitudes of fMRI variability across movements in a variety of motor system areas. These fMRI variability magnitudes were also consistent across movements to different targets when performed with either arm. Cortical fMRI variability in the posterior-parietal cortex of individual subjects explained their movement-extent variability. This relationship was apparent only in posterior-parietal cortex and not in other motor system areas, thereby suggesting that individuals with more variable movement preparation exhibit larger kinematic variability. We therefore propose that neural and kinematic variability are reliable and interrelated individual characteristics that may predispose individual subjects to exhibit distinct motor capabilities. SIGNIFICANCE STATEMENT Neural activity and movement kinematics are remarkably variable. Although intertrial variability is rarely studied, here, we demonstrate that individual human subjects exhibit distinct magnitudes of neural and kinematic variability that are reproducible across movements to different targets and when performing these movements with either arm. Furthermore, when examining the relationship between cortical variability and movement variability, we find that cortical fMRI variability in parietal cortex of individual subjects explained their movement extent variability. This enabled us to explain why some subjects

  10. On the internal representation of numerical magnitude and physical size.

    Science.gov (United States)

    Fitousi, Daniel

    2014-01-01

    A nascent idea in the numerical cognition literature--the analogical hypothesis (Pinel, Piazza, Bihan, & Dehaene, 2004)--assumes a common noisy code for the representation of symbolic (e.g., numerals) and nonsymbolic (e.g., numerosity, physical size, luminance) magnitudes. The present work subjected this assumption to various tests from the perspective of General Recognition Theory (GRT; Ashby &Townsend, 1986)--a multidimensional extension of Signal Detection Theory (Green & Swets, 1966). The GRT was applied to the dimensions of numerical magnitude and physical size with the following goals: (a) characterizing the internal representation of these dimensions in the psychological space, and (b) assessing various types of (in)dependence and separability governing the perception of these dimensions. The results revealed various violations of independence and separability with Stroop incongruent, but not with Stroop congruent stimuli. The outcome suggests that there are deep differences in architecture between Stroop congruent and incongruent stimuli that reach well beyond the semantic relationship involved.

  11. On the frequency-magnitude law for fractal seismicity

    International Nuclear Information System (INIS)

    Molchan, G.; Kronrod, T.

    2004-09-01

    Scaling analysis of seismicity in the space-time-magnitude domain very often starts from the relation λ(m, L = a L 10 -bm L c for the rate of seismic events of magnitude M > m in an area of size L. There are some evidences in favor of multifractal property of seismic process. In this case the choice of the scale exponent 'c' is not unique. It is shown how different 'c's are related to different types of spatial averaging applied to λ (m, L) and what are the 'c's for which the distributions of a L best agree for small L. Theoretical analysis is supplemented with an analysis of California data for which the above issues were recently discussed on an empirical level. (author)

  12. EARTHQUAKE-INDUCED DEFORMATION STRUCTURES AND RELATED TO EARTHQUAKE MAGNITUDES

    Directory of Open Access Journals (Sweden)

    Savaş TOPAL

    2003-02-01

    Full Text Available Earthquake-induced deformation structures which are called seismites may helpful to clasify the paleoseismic history of a location and to estimate the magnitudes of the potention earthquakes in the future. In this paper, seismites were investigated according to the types formed in deep and shallow lake sediments. Seismites are observed forms of sand dikes, introduced and fractured gravels and pillow structures in shallow lakes and pseudonodules, mushroom-like silts protruding laminites, mixed layers, disturbed varved lamination and loop bedding in deep lake sediments. Earthquake-induced deformation structures, by benefiting from previous studies, were ordered according to their formations and earthquake magnitudes. In this order, the lowest eartquake's record is loop bedding and the highest one is introduced and fractured gravels in lacustrine deposits.

  13. THE ABSOLUTE MAGNITUDES OF TYPE Ia SUPERNOVAE IN THE ULTRAVIOLET

    International Nuclear Information System (INIS)

    Brown, Peter J.; Roming, Peter W. A.; Ciardullo, Robin; Gronwall, Caryl; Hoversten, Erik A.; Pritchard, Tyler; Milne, Peter; Bufano, Filomena; Mazzali, Paolo; Elias-Rosa, Nancy; Filippenko, Alexei V.; Li Weidong; Foley, Ryan J.; Hicken, Malcolm; Kirshner, Robert P.; Gehrels, Neil; Holland, Stephen T.; Immler, Stefan; Phillips, Mark M.; Still, Martin

    2010-01-01

    We examine the absolute magnitudes and light-curve shapes of 14 nearby (redshift z = 0.004-0.027) Type Ia supernovae (SNe Ia) observed in the ultraviolet (UV) with the Swift Ultraviolet/Optical Telescope. Colors and absolute magnitudes are calculated using both a standard Milky Way extinction law and one for the Large Magellanic Cloud that has been modified by circumstellar scattering. We find very different behavior in the near-UV filters (uvw1 rc covering ∼2600-3300 A after removing optical light, and u ∼ 3000-4000 A) compared to a mid-UV filter (uvm2 ∼2000-2400 A). The uvw1 rc - b colors show a scatter of ∼0.3 mag while uvm2-b scatters by nearly 0.9 mag. Similarly, while the scatter in colors between neighboring filters is small in the optical and somewhat larger in the near-UV, the large scatter in the uvm2 - uvw1 colors implies significantly larger spectral variability below 2600 A. We find that in the near-UV the absolute magnitudes at peak brightness of normal SNe Ia in our sample are correlated with the optical decay rate with a scatter of 0.4 mag, comparable to that found for the optical in our sample. However, in the mid-UV the scatter is larger, ∼1 mag, possibly indicating differences in metallicity. We find no strong correlation between either the UV light-curve shapes or the UV colors and the UV absolute magnitudes. With larger samples, the UV luminosity might be useful as an additional constraint to help determine distance, extinction, and metallicity in order to improve the utility of SNe Ia as standardized candles.

  14. METHOD FOR SOLVING FUZZY ASSIGNMENT PROBLEM USING MAGNITUDE RANKING TECHNIQUE

    OpenAIRE

    D. Selvi; R. Queen Mary; G. Velammal

    2017-01-01

    Assignment problems have various applications in the real world because of their wide applicability in industry, commerce, management science, etc. Traditional classical assignment problems cannot be successfully used for real life problem, hence the use of fuzzy assignment problems is more appropriate. In this paper, the fuzzy assignment problem is formulated to crisp assignment problem using Magnitude Ranking technique and Hungarian method has been applied to find an optimal solution. The N...

  15. Improving Children’s Knowledge of Fraction Magnitudes

    Science.gov (United States)

    Fazio, Lisa K.; Kennedy, Casey A.; Siegler, Robert S.

    2016-01-01

    We examined whether playing a computerized fraction game, based on the integrated theory of numerical development and on the Common Core State Standards’ suggestions for teaching fractions, would improve children’s fraction magnitude understanding. Fourth and fifth-graders were given brief instruction about unit fractions and played Catch the Monster with Fractions, a game in which they estimated fraction locations on a number line and received feedback on the accuracy of their estimates. The intervention lasted less than 15 minutes. In our initial study, children showed large gains from pretest to posttest in their fraction number line estimates, magnitude comparisons, and recall accuracy. In a more rigorous second study, the experimental group showed similarly large improvements, whereas a control group showed no improvement from practicing fraction number line estimates without feedback. The results provide evidence for the effectiveness of interventions emphasizing fraction magnitudes and indicate how psychological theories and research can be used to evaluate specific recommendations of the Common Core State Standards. PMID:27768756

  16. Correlating precursory declines in groundwater radon with earthquake magnitude.

    Science.gov (United States)

    Kuo, T

    2014-01-01

    Both studies at the Antung hot spring in eastern Taiwan and at the Paihe spring in southern Taiwan confirm that groundwater radon can be a consistent tracer for strain changes in the crust preceding an earthquake when observed in a low-porosity fractured aquifer surrounded by a ductile formation. Recurrent anomalous declines in groundwater radon were observed at the Antung D1 monitoring well in eastern Taiwan prior to the five earthquakes of magnitude (Mw ): 6.8, 6.1, 5.9, 5.4, and 5.0 that occurred on December 10, 2003; April 1, 2006; April 15, 2006; February 17, 2008; and July 12, 2011, respectively. For earthquakes occurring on the longitudinal valley fault in eastern Taiwan, the observed radon minima decrease as the earthquake magnitude increases. The above correlation has been proven to be useful for early warning local large earthquakes. In southern Taiwan, radon anomalous declines prior to the 2010 Mw 6.3 Jiasian, 2012 Mw 5.9 Wutai, and 2012 ML 5.4 Kaohsiung earthquakes were also recorded at the Paihe spring. For earthquakes occurring on different faults in southern Taiwan, the correlation between the observed radon minima and the earthquake magnitude is not yet possible. © 2013, National Ground Water Association.

  17. Regional moment: Magnitude relations for earthquakes and explosions

    Energy Technology Data Exchange (ETDEWEB)

    Patton, H.J.; Walter, W.R. (Lawrence Livermore National Lab., CA (United States))

    1993-02-19

    The authors present M[sub o]:m[sub b] relations using m[sub b](P[sub n]) and m[sub b](L[sub g]) for earthquakes and explosions occurring in tectonic and stable areas. The observations for m[sub b](P[sub n]) range from about 3 to 6 and show excellent separation between earthquakes and explosions on M[sub o]:m[sub b] plots, independent of the magnitude. The scatter in M[sub o]:M[sub b] observations for NTS explosions is small compared to the earthquake data. The M[sub o]:m[sub b](L[sub g]) data for Soviet explosions overlay the observations for US explosions. These results, and the small scatter for NTS explosions, suggest weak dependence of M[sub o]:m[sub b] relations on emplacement media. A simple theoretical model is developed which matches all these observations. The model uses scaling similarity and conservation of energy to provide a physical link between seismic moment and a broadband seismic magnitude. Three factors, radiation pattern, material property, and apparent stress, contribute to the separation between earthquakes and explosions. This theoretical separation is independent of broadband magnitude. For US explosions in different media, the material property and apparent stress contributions are shown to compensate for one another, supporting the observations that M[sub o]:M[sub b] is nearly independent of source geology. 19 refs., 2 figs., 1 tab.

  18. Number magnitude to finger mapping is disembodied and topological.

    Science.gov (United States)

    Plaisier, Myrthe A; Smeets, Jeroen B J

    2011-03-01

    It has been shown that humans associate fingers with numbers because finger counting strategies interact with numerical judgements. At the same time, there is evidence that there is a relation between number magnitude and space as small to large numbers seem to be represented from left to right. In the present study, we investigated whether number magnitude to finger mapping is embodied (related to the order of fingers on the hand) or disembodied (spatial). We let healthy human volunteers name random numbers between 1 and 30, while simultaneously tapping a random finger. Either the hands were placed directly next to each other, 30 cm apart, or the hands were crossed such that the left hand was on the right side of the body mid-line. The results show that naming a smaller number than the previous one was associated with tapping a finger to the left of the previously tapped finger. This shows that there is a spatial (disembodied) mapping between number magnitude and fingers. Furthermore, we show that this mapping is topological rather than metrically scaled.

  19. Automated Determination of Magnitude and Source Length of Large Earthquakes

    Science.gov (United States)

    Wang, D.; Kawakatsu, H.; Zhuang, J.; Mori, J. J.; Maeda, T.; Tsuruoka, H.; Zhao, X.

    2017-12-01

    Rapid determination of earthquake magnitude is of importance for estimating shaking damages, and tsunami hazards. However, due to the complexity of source process, accurately estimating magnitude for great earthquakes in minutes after origin time is still a challenge. Mw is an accurate estimate for large earthquakes. However, calculating Mw requires the whole wave trains including P, S, and surface phases, which takes tens of minutes to reach stations at tele-seismic distances. To speed up the calculation, methods using W phase and body wave are developed for fast estimating earthquake sizes. Besides these methods that involve Green's Functions and inversions, there are other approaches that use empirically simulated relations to estimate earthquake magnitudes, usually for large earthquakes. The nature of simple implementation and straightforward calculation made these approaches widely applied at many institutions such as the Pacific Tsunami Warning Center, the Japan Meteorological Agency, and the USGS. Here we developed an approach that was originated from Hara [2007], estimating magnitude by considering P-wave displacement and source duration. We introduced a back-projection technique [Wang et al., 2016] instead to estimate source duration using array data from a high-sensitive seismograph network (Hi-net). The introduction of back-projection improves the method in two ways. Firstly, the source duration could be accurately determined by seismic array. Secondly, the results can be more rapidly calculated, and data derived from farther stations are not required. We purpose to develop an automated system for determining fast and reliable source information of large shallow seismic events based on real time data of a dense regional array and global data, for earthquakes that occur at distance of roughly 30°- 85° from the array center. This system can offer fast and robust estimates of magnitudes and rupture extensions of large earthquakes in 6 to 13 min (plus

  20. Estuarine abandoned channel sedimentation rates record peak fluvial discharge magnitudes

    Science.gov (United States)

    Gray, A. B.; Pasternack, G. B.; Watson, E. B.

    2018-04-01

    Fluvial sediment deposits can provide useful records of integrated watershed expressions including flood event magnitudes. However, floodplain and estuarine sediment deposits evolve through the interaction of watershed/marine sediment supply and transport characteristics with the local depositional environment. Thus extraction of watershed scale signals depends upon accounting for local scale effects on sediment deposition rates and character. This study presents an examination of the balance of fluvial sediment dynamics and local scale hydro-geomorphic controls on alluviation of an abandoned channel in the Salinas River Lagoon, CA. A set of three sediment cores contained discrete flood deposits that corresponded to the largest flood events over the period of accretion from 1969 to 2007. Sedimentation rates scaled with peak flood discharge and event scale sediment flux, but were not influenced by longer scale hydro-meteorological activities such as annual precipitation and water yield. Furthermore, the particle size distributions of flood deposits showed no relationship to event magnitudes. Both the responsiveness of sedimentation and unresponsiveness of particle size distributions to hydro-sedimentological event magnitudes appear to be controlled by aspects of local geomorphology that influence the connectivity of the abandoned channel to the Salinas River mainstem. Well-developed upstream plug bar formation precluded the entrainment of coarser bedload into the abandoned channel, while Salinas River mouth conditions (open/closed) in conjunction with tidal and storm surge conditions may play a role in influencing the delivery of coarser suspended load fractions. Channel adjacent sediment deposition can be valuable records of hydro-meteorological and sedimentological regimes, but local depositional settings may dominate the character of short term (interdecadal) signatures.

  1. Evaluation of the magnitude of EBT Gafchromic film polarization effects.

    Science.gov (United States)

    Butson, M J; Cheung, T; Yu, P K N

    2009-03-01

    Gafchromic EBT film, has become a main dosimetric tools for quantitative evaluation of radiation doses in radiation therapy application. One aspect of variability using EBT Gafchromic film is the magnitude of the orientation effect when analysing the film in landscape or portrait mode. This work has utilized a > 99% plane polarized light source and a non-polarized diffuse light source to investigate the absolute magnitude of EBT Gafchromic films polarization or orientation effects. Results have shown that using a non-polarized light source produces a negligible orientation effect for EBT Gafchromic film and thus the angle of orientation is not important. However, the film exhibits a significant variation in transmitted optical density with angle of orientation to polarized light producing more than 100% increase, or over a doubling of measured OD for films irradiated with x-rays up to dose levels of 5 Gy. The maximum optical density was found to be in a plane at an angle of 14 degrees +/- 7 degrees (2 SD) when the polarizing sheet is turned clockwise with respect to the film. As the magnitude of the orientation effect follows a sinusoidal shape it becomes more critical for alignment accuracy of the film with respect to the polarizing direction in the anticlockwise direction as this will place the alignment of the polarizing axes on the steeper gradient section of the sinusoidal pattern. An average change of 4.5% per 5 degrees is seen for an anticlockwise polarizer rotation where as the effect is 1.2% per 5 degrees for an clockwise polarizer rotation. This may have consequences to the positional accuracy of placement of the EBT Gafchromic film on a scanner as even a 1 degree alignment error can cause an approximate 1% error in analysis. The magnitude of the orientation effect is therefore dependant on the degree of polarization of the scanning light source and can range from negligible (diffuse LED light source) through to more than 100% or doubling of OD variation

  2. Evaluation of the magnitude of EBT Gafchromic film polarization effects

    International Nuclear Information System (INIS)

    Cheung, T.; Yu, P.K.N.; Butson, M.J.

    2009-01-01

    Gafchromic EBT film, has become a main dosimetric tools for quantitative evaluation of radiation doses in radiation therapy application. One aspect of variability using EBT Gafchromic film is the magnitude of the orientation effect when analysing the film in landscape or portrait mode. This work has utilized a >99% plane polarized light source a non-polarized diffuse light source to investigate the absolute magnitude of EBT Gafchromic films polarization or orientation effects. Results have shown that using a non-polarized light source produces a negligible orientation effect for EBT Gafchromic film and thus the angle of orientation is not important. However, the film exhibits a significant variation in transmitted optical density with angle of orientation to polarized light producing more than 100% increase, or over a doubling of measured O D for films irradiated with x-rays up to dose levels of 5 Gy. The maximum optical density was found to be in a plane at an angle of 14 0 ± 7 0 (2 S D) when the polarizing sheet is turned clockwise with respect to the film. As the magnitude of the orientation effects follows a sinusoidal shape it becomes more critical for alignment accuracy of the film with respect to the polarizing direction in the anticlockwise direction as this will place the alignment of the polarizing axes on the steeper gradient section of the sinusoidal pattern. An average change of 4.5 % per 5 0 is seen for an anticlockwise polarizer rotation where as the effect is 1.2 % per 5 0 for an clockwise polarizer rotation. This may have consequences to the positional accuracy of placement of the EBT Gafchromic film on a scanner as even a 1 0 alignment error can cause an approximate 1 % error in analysis. The magnitude of the orientation effect is therefore dependant on the degree of polarization of the scanning light source and can range from negligible (diffuse LED light source) through to more than 100% or doubling of O D variation with a fully linear

  3. Magnitude of bacteraemia predicts one-year mortality

    DEFF Research Database (Denmark)

    Gradel, Kim Oren; Schønheyder, Henrik Carl; Søgaard, Mette

    Objectives: All hospitals in our region use the BacT/Alert® blood culture (BC) system with a 3-bottle BC set for adults. We hypothesized that the magnitude of bacteremia (i.e., number of positive bottles in the initial BC set) predicted one-year mortality. Methods In a population-based study we...... with a BC index of 1 (i.e., one positive bottle) were chosen as the reference group. We computed Kaplan-Meier curves and performed Cox regression analyses to estimate mortality rate ratios (MRRs) with 95 % confidence intervals [CIs] 30 and 365 days after the initial BC sampling date, first in crude analyses...... mortality....

  4. Color Magnitude Diagrams of Old, Massive GCs in M31

    Science.gov (United States)

    Caldwell, Nelson; Williams, B.; Dolphin, A. E.; Johnson, L. C.; Weisz, D. R.

    2013-01-01

    Multicolor stellar photometry of HST data of M31 collected as part of the PHAT project has been performed using the DOLPHOT suite of programs. We present results of color-magnitude diagrams created in F475W and F814W (BI) of more than 50 massive, old clusters. These are clusters in or projected on the disk. We compare the metallicities derived from the color of the giant branch stars with that derived from integrated light spectroscopy. As well, we compare the ages of massive, young clusters with those found from spectra.

  5. Large magnitude earthquakes on the Awatere Fault, Marlborough

    International Nuclear Information System (INIS)

    Mason, D.P.M.; Little, T.A.; Van Dissen, R.J.

    2006-01-01

    The Awatere Fault is a principal active strike-slip fault within the Marlborough fault system, and last ruptured in October 1848, in the M w ∼7.5 Marlborough earthquake. The coseismic slip distribution and maximum traceable length of this rupture are calculated from the magnitude and distribution of small, metre-scale geomorphic displacements attributable to this earthquake. These data suggest this event ruptured ∼110 km of the fault, with mean horizontal surface displacement of 5.3 ± 1.6m. Based on these parameters, the moment magnitude of this earthquake would be M w ∼7.4-7.7. Paeloseismic trenching investigations along the eastern section reveal evidence for at least eight, and possibly ten, surface-rupturing paleoearthquakes in the last 8600 years, including the 1848 rupture. The coseismic slip distribution and rupture length of the 1848 earthquake, in combination with the paleoearthquake age data, suggest the eastern section of the Awatere Fault ruptures in M w ∼7.5 earthquakes, with over 5 m of surface displacement, every 860-1080 years. (author). 21 refs., 10 figs., 7 tabs

  6. On the Real Magnitude of Psychological Sex Differences

    Directory of Open Access Journals (Sweden)

    Marco Del Giudice

    2009-04-01

    Full Text Available A comprehensive evolutionary theory of sex differences will benefit from an accurate assessment of their magnitude across different psychological domains. This article shows that mainstream research has severely underestimated the magnitude of psychological sex differences; the reason lies in the common practice of measuring multidimensional differences one dimension at a time, without integrating them into a proper multivariate effect size (ES. Employing the Mahalanobis distance D (the multivariate generalization of Cohen's d results in more accurate, and predictably larger, estimates of overall sex differences in multidimensional constructs. Two real-world examples are presented: (1 In a published dataset on Big Five personality traits, sex differences on individual scales averaged d = .27, a typical ES conventionally regarded as “small.” However, the overall difference was D = .84 (disattenuated D = .98, implying considerable statistical separation between male and female distributions. (2 In a recent meta-analytic summary of sex differences in aggression, the individual ESs averaged d = .34. However, the overall difference was estimated at D = .75 – .80 (disattenuated D = .89–1.01. In many psychological domains, sex differences may be substantially larger than previously acknowledged.

  7. Local magnitude scale for Valle Medio del Magdalena region, Colombia

    Science.gov (United States)

    Londoño, John Makario; Romero, Jaime A.

    2017-12-01

    A local Magnitude (ML) scale for Valle Medio del Magdalena (VMM) region was defined by using 514 high quality earthquakes located at VMM area and inversion of 2797 amplitude values of horizontal components of 17 stations seismic broad band stations, simulated in a Wood-Anderson seismograph. The derived local magnitude scale for VMM region was: ML =log(A) + 1.3744 ∗ log(r) + 0.0014776 ∗ r - 2.397 + S Where A is the zero-to-peak amplitude in nm in horizontal components, r is the hypocentral distance in km, and S is the station correction. Higher values of ML were obtained for VMM region compared with those obtained with the current formula used for ML determination, and with California formula. With this new scale ML values are adjusted to local conditions beneath VMM region leading to more realistic ML values. Moreover, with this new ML scale the seismicity caused by tectonic or fracking activity at VMM region can be monitored more accurately.

  8. Optimal updating magnitude in adaptive flat-distribution sampling.

    Science.gov (United States)

    Zhang, Cheng; Drake, Justin A; Ma, Jianpeng; Pettitt, B Montgomery

    2017-11-07

    We present a study on the optimization of the updating magnitude for a class of free energy methods based on flat-distribution sampling, including the Wang-Landau (WL) algorithm and metadynamics. These methods rely on adaptive construction of a bias potential that offsets the potential of mean force by histogram-based updates. The convergence of the bias potential can be improved by decreasing the updating magnitude with an optimal schedule. We show that while the asymptotically optimal schedule for the single-bin updating scheme (commonly used in the WL algorithm) is given by the known inverse-time formula, that for the Gaussian updating scheme (commonly used in metadynamics) is often more complex. We further show that the single-bin updating scheme is optimal for very long simulations, and it can be generalized to a class of bandpass updating schemes that are similarly optimal. These bandpass updating schemes target only a few long-range distribution modes and their optimal schedule is also given by the inverse-time formula. Constructed from orthogonal polynomials, the bandpass updating schemes generalize the WL and Langfeld-Lucini-Rago algorithms as an automatic parameter tuning scheme for umbrella sampling.

  9. The absolute magnitude distribution of Kuiper Belt objects

    Energy Technology Data Exchange (ETDEWEB)

    Fraser, Wesley C. [Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Brown, Michael E. [Division of Geological and Planetary Sciences, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Morbidelli, Alessandro [Laboratoire Lagrange, UMR7293, Université de Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d' Azur, BP 4229, F-06304 Nice (France); Parker, Alex [Department of Astronomy, University of California at Berkeley, Berkeley, CA 94720 (United States); Batygin, Konstantin, E-mail: wesley.fraser@nrc.ca [Institute for Theory and Computation, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS 51, Cambridge, MA 02138 (United States)

    2014-02-20

    Here we measure the absolute magnitude distributions (H-distribution) of the dynamically excited and quiescent (hot and cold) Kuiper Belt objects (KBOs), and test if they share the same H-distribution as the Jupiter Trojans. From a compilation of all useable ecliptic surveys, we find that the KBO H-distributions are well described by broken power laws. The cold population has a bright-end slope, α{sub 1}=1.5{sub −0.2}{sup +0.4}, and break magnitude, H{sub B}=6.9{sub −0.2}{sup +0.1} (r'-band). The hot population has a shallower bright-end slope of, α{sub 1}=0.87{sub −0.2}{sup +0.07}, and break magnitude H{sub B}=7.7{sub −0.5}{sup +1.0}. Both populations share similar faint-end slopes of α{sub 2} ∼ 0.2. We estimate the masses of the hot and cold populations are ∼0.01 and ∼3 × 10{sup –4} M {sub ⊕}. The broken power-law fit to the Trojan H-distribution has α{sub 1} = 1.0 ± 0.2, α{sub 2} = 0.36 ± 0.01, and H {sub B} = 8.3. The Kolmogorov-Smirnov test reveals that the probability that the Trojans and cold KBOs share the same parent H-distribution is less than 1 in 1000. When the bimodal albedo distribution of the hot objects is accounted for, there is no evidence that the H-distributions of the Trojans and hot KBOs differ. Our findings are in agreement with the predictions of the Nice model in terms of both mass and H-distribution of the hot and Trojan populations. Wide-field survey data suggest that the brightest few hot objects, with H{sub r{sup ′}}≲3, do not fall on the steep power-law slope of fainter hot objects. Under the standard hierarchical model of planetesimal formation, it is difficult to account for the similar break diameters of the hot and cold populations given the low mass of the cold belt.

  10. The absolute magnitude distribution of Kuiper Belt objects

    International Nuclear Information System (INIS)

    Fraser, Wesley C.; Brown, Michael E.; Morbidelli, Alessandro; Parker, Alex; Batygin, Konstantin

    2014-01-01

    Here we measure the absolute magnitude distributions (H-distribution) of the dynamically excited and quiescent (hot and cold) Kuiper Belt objects (KBOs), and test if they share the same H-distribution as the Jupiter Trojans. From a compilation of all useable ecliptic surveys, we find that the KBO H-distributions are well described by broken power laws. The cold population has a bright-end slope, α 1 =1.5 −0.2 +0.4 , and break magnitude, H B =6.9 −0.2 +0.1 (r'-band). The hot population has a shallower bright-end slope of, α 1 =0.87 −0.2 +0.07 , and break magnitude H B =7.7 −0.5 +1.0 . Both populations share similar faint-end slopes of α 2 ∼ 0.2. We estimate the masses of the hot and cold populations are ∼0.01 and ∼3 × 10 –4 M ⊕ . The broken power-law fit to the Trojan H-distribution has α 1 = 1.0 ± 0.2, α 2 = 0.36 ± 0.01, and H B = 8.3. The Kolmogorov-Smirnov test reveals that the probability that the Trojans and cold KBOs share the same parent H-distribution is less than 1 in 1000. When the bimodal albedo distribution of the hot objects is accounted for, there is no evidence that the H-distributions of the Trojans and hot KBOs differ. Our findings are in agreement with the predictions of the Nice model in terms of both mass and H-distribution of the hot and Trojan populations. Wide-field survey data suggest that the brightest few hot objects, with H r ′ ≲3, do not fall on the steep power-law slope of fainter hot objects. Under the standard hierarchical model of planetesimal formation, it is difficult to account for the similar break diameters of the hot and cold populations given the low mass of the cold belt.

  11. Temporal and spatial variations in the magnitude of completeness for homogenized moment magnitude catalogue for northeast India

    Science.gov (United States)

    Das, Ranjit; Wason, H. R.; Sharma, M. L.

    2012-02-01

    Northeast India region is one of the most seismically active areas in the world. Events data for the period 1897-2010, used in this study has been largely compiled from global ISC, NEIC and GCMT databases. Historical seismicity catalogue of Gupta et al (1986) and some events data from the bulletins of India Meteorological Department are also used. Orthogonal regression relations for conversion of body and surface wave magnitudes to M w,HRVD based on events data for the period 1978-2006 have been derived. An Orthogonal Standard Regression (OSR) relationship has also been obtained for scaling of intensity estimates to M w,NEIC using 126 global intensity events with intensity VI or greater during the period 1975-2010. Magnitude of completeness and Gutenberg-Richter (GR) recurrence parameter values have been determined for the declustered homogenized catalogue pertaining to four different time periods namely, 1897-1963, 1964-1990, 1964-2000 and 1964-2010. The M c and ` b' values are observed to decrease and increase, respectively, with addition of newer data with time. The study region has been subdivided into nine seismogenic zones keeping in view the spatial variations in earthquake occurrence and prevalent tectonics. M c, ` b' and ` a' values have been estimated with respect to each zone, and the variations in the values of these parameters have been analysed.

  12. Aerogel Antennas Communications Study Using Error Vector Magnitude Measurements

    Science.gov (United States)

    Miranda, Felix A.; Mueller, Carl H.; Meador, Mary Ann B.

    2014-01-01

    This presentation discusses an aerogel antennas communication study using error vector magnitude (EVM) measurements. The study was performed using 2x4 element polyimide (PI) aerogel-based phased arrays designed for operation at 5 GHz as transmit (Tx) and receive (Rx) antennas separated by a line of sight (LOS) distance of 8.5 meters. The results of the EVM measurements demonstrate that polyimide aerogel antennas work appropriately to support digital communication links with typically used modulation schemes such as QPSK and 4 DQPSK. As such, PI aerogel antennas with higher gain, larger bandwidth and lower mass than typically used microwave laminates could be suitable to enable aerospace-to- ground communication links with enough channel capacity to support voice, data and video links from CubeSats, unmanned air vehicles (UAV), and commercial aircraft.

  13. Magnitude and Distribution of Flows into Northeastern Florida Bay

    Science.gov (United States)

    Patino, Eduardo; Hittle, Clinton D.

    2000-01-01

    Changes in water-management practices have been made to accommodate a large and rapidly growing urban population along the Atlantic Coast and to meet the demand for intensive agricultural activities. These changes have resulted in a highly managed hydrologic system consisting of numerous canals, levees, control structures, and pumping stations that have altered the hydrology of the Everglades and Florida Bay ecosystems. Over the past decade, Florida Bay has experienced sea-grass die-off and algal blooms, which are indicators of ecological change attributed primarily to the increase in salinity and nutrient content of bay waters. Because plans are to restore sheetflow in the Everglades wetlands to its natural state, water managers anticipate a change in the magnitude and timing of freshwater exiting the mainland through the creeks that cut through the embankment or as sheetflow into Florida Bay.

  14. Real time monitoring of moment magnitude by waveform inversion

    Science.gov (United States)

    Lee, J.; Friederich, W.; Meier, T.

    2012-01-01

    An instantaneous measure of the moment magnitude (Mw) of an ongoing earthquake is estimated from the moment rate function (MRF) determined in real-time from available seismic data using waveform inversion. Integration of the MRF gives the moment function from which an instantaneous Mw is derived. By repeating the inversion procedure at regular intervals while seismic data are coming in we can monitor the evolution of seismic moment and Mw with time. The final size and duration of a strong earthquake can be obtained within 12 to 15 minutes after the origin time. We show examples of Mw monitoring for three large earthquakes at regional distances. The estimated Mw is only weakly sensitive to changes in the assumed source parameters. Depending on the availability of seismic stations close to the epicenter, a rapid estimation of the Mw as a prerequisite for the assessment of earthquake damage potential appears to be feasible.

  15. Aerogel Antennas Communications Study Using Error Vector Magnitude Measurements

    Science.gov (United States)

    Miranda, Felix A.; Mueller, Carl H.; Meador, Mary Ann B.

    2014-01-01

    This paper discusses an aerogel antennas communication study using error vector magnitude (EVM) measurements. The study was performed using 4x2 element polyimide (PI) aerogel-based phased arrays designed for operation at 5 GHz as transmit (Tx) and receive (Rx) antennas separated by a line of sight (LOS) distance of 8.5 meters. The results of the EVM measurements demonstrate that polyimide aerogel antennas work appropriately to support digital communication links with typically used modulation schemes such as QPSK and pi/4 DQPSK. As such, PI aerogel antennas with higher gain, larger bandwidth and lower mass than typically used microwave laminates could be suitable to enable aerospace-to-ground communication links with enough channel capacity to support voice, data and video links from cubesats, unmanned air vehicles (UAV), and commercial aircraft.

  16. Breach Risk Magnitude: A Quantitative Measure of Database Security.

    Science.gov (United States)

    Yasnoff, William A

    2016-01-01

    A quantitative methodology is described that provides objective evaluation of the potential for health record system breaches. It assumes that breach risk increases with the number of potential records that could be exposed, while it decreases when more authentication steps are required for access. The breach risk magnitude (BRM) is the maximum value for any system user of the common logarithm of the number of accessible database records divided by the number of authentication steps needed to achieve such access. For a one million record relational database, the BRM varies from 5.52 to 6 depending on authentication protocols. For an alternative data architecture designed specifically to increase security by separately storing and encrypting each patient record, the BRM ranges from 1.3 to 2.6. While the BRM only provides a limited quantitative assessment of breach risk, it may be useful to objectively evaluate the security implications of alternative database organization approaches.

  17. Magnitude of the current in 2D interlayer tunneling devices.

    Science.gov (United States)

    Feenstra, Randall M; de la Barrera, Sergio C; Li, Jun; Nie, Yifan; Cho, Kyeongjae

    2018-01-15

    Using the Bardeen tunneling method with first-principles wave functions, computations are made of the tunneling current in graphene/hexagonal-boron-nitride/graphene (G/h-BN/G) vertical structures. Detailed comparison with prior experimental results is made, focusing on the magnitude of the achievable tunnel current. With inclusion of the effects of translational and rotational misalignment of the graphene and the h-BN, predicted currents are found to be about 15×  larger than experimental values. A reduction in this discrepancy, to a factor of 2.5×, is achieved by utilizing a realistic size for the band gap of the h-BN, hence affecting the exponential decay constant for the tunneling.

  18. THE ABSOLUTE MAGNITUDE OF RRc VARIABLES FROM STATISTICAL PARALLAX

    International Nuclear Information System (INIS)

    Kollmeier, Juna A.; Burns, Christopher R.; Thompson, Ian B.; Preston, George W.; Crane, Jeffrey D.; Madore, Barry F.; Morrell, Nidia; Prieto, José L.; Shectman, Stephen; Simon, Joshua D.; Villanueva, Edward; Szczygieł, Dorota M.; Gould, Andrew; Sneden, Christopher; Dong, Subo

    2013-01-01

    We present the first definitive measurement of the absolute magnitude of RR Lyrae c-type variable stars (RRc) determined purely from statistical parallax. We use a sample of 242 RRc variables selected from the All Sky Automated Survey for which high-quality light curves, photometry, and proper motions are available. We obtain high-resolution echelle spectra for these objects to determine radial velocities and abundances as part of the Carnegie RR Lyrae Survey. We find that M V,RRc = 0.59 ± 0.10 at a mean metallicity of [Fe/H] = –1.59. This is to be compared with previous estimates for RRab stars (M V,RRab = 0.76 ± 0.12) and the only direct measurement of an RRc absolute magnitude (RZ Cephei, M V,RRc = 0.27 ± 0.17). We find the bulk velocity of the halo relative to the Sun to be (W π , W θ , W z ) = (12.0, –209.9, 3.0) km s –1 in the radial, rotational, and vertical directions with dispersions (σ W π ,σ W θ ,σ W z ) = (150.4, 106.1, 96.0) km s -1 . For the disk, we find (W π , W θ , W z ) = (13.0, –42.0, –27.3) km s –1 relative to the Sun with dispersions (σ W π ,σ W θ ,σ W z ) = (67.7,59.2,54.9) km s -1 . Finally, as a byproduct of our statistical framework, we are able to demonstrate that UCAC2 proper-motion errors are significantly overestimated as verified by UCAC4

  19. Refractive error magnitude and variability: Relation to age.

    Science.gov (United States)

    Irving, Elizabeth L; Machan, Carolyn M; Lam, Sharon; Hrynchak, Patricia K; Lillakas, Linda

    2018-03-19

    To investigate mean ocular refraction (MOR) and astigmatism, over the human age range and compare severity of refractive error to earlier studies from clinical populations having large age ranges. For this descriptive study patient age, refractive error and history of surgery affecting refraction were abstracted from the Waterloo Eye Study database (WatES). Average MOR, standard deviation of MOR and astigmatism were assessed in relation to age. Refractive distributions for developmental age groups were determined. MOR standard deviation relative to average MOR was evaluated. Data from earlier clinically based studies with similar age ranges were compared to WatES. Right eye refractive errors were available for 5933 patients with no history of surgery affecting refraction. Average MOR varied with age. Children <1 yr of age were the most hyperopic (+1.79D) and the highest magnitude of myopia was found at 27yrs (-2.86D). MOR distributions were leptokurtic, and negatively skewed. The mode varied with age group. MOR variability increased with increasing myopia. Average astigmatism increased gradually to age 60 after which it increased at a faster rate. By 85+ years it was 1.25D. J 0 power vector became increasingly negative with age. J 45 power vector values remained close to zero but variability increased at approximately 70 years. In relation to comparable earlier studies, WatES data were most myopic. Mean ocular refraction and refractive error distribution vary with age. The highest magnitude of myopia is found in young adults. Similar to prevalence, the severity of myopia also appears to have increased since 1931. Copyright © 2018 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

  20. Large Contrast Between the Moment Magnitude of Tremor and the Moment Magnitude of Slip in ETS Events

    Science.gov (United States)

    Kao, H.; Wang, K.; Dragert, H.; Rogers, G. C.; Kao, J. Y.

    2009-12-01

    We have developed an algorithm to estimate the moment magnitudes (Mw) of seismic tremors that are recorded during episodic tremor and slip (ETS) events beneath the northern Cascadia margin. The tremor “cloud” during an ETS episode consists of numerous individual tremor bursts. For each tremor burst, the hypocenter is first determined by the Source-Scanning Algorithm [Kao and Shan, 2004]. From the derived source location, we calculate a set of synthetic seismograms for each station based on a fixed seismic moment but different focal mechanisms. The maximum tremor amplitude observed at each station is then compared to that of the synthetics to give an estimate of the corresponding seismic moment of the tremor burst. The seismic moment averaged over all stations is used to calculate the final tremor burst Mw. We have applied this method to local earthquakes for calibration and the results are very consistent with the magnitudes listed in the catalogue. For each of the 8 northern Cascadia ETS episodes whose GPS coverage is sufficient for slip distribution inversion, the cumulative tremor Mw for the entire tremor cloud, determined from the combined moments of all individual tremor bursts in the ETS episode, is ~3 orders less than the corresponding slip Mw in the same episode (e.g., 3.7 vs. 6.7). This result suggests that aseismic slip is the predominant mode of deformation during ETS. The majority of individual tremor bursts in northern Cascadia have Mw ranging between 1.0 and 1.7 with the mean of 1.34. Only 5% of all tremors are larger than 2.0 with the largest being ~2.5.

  1. THE ABSOLUTE MAGNITUDE OF RRc VARIABLES FROM STATISTICAL PARALLAX

    Energy Technology Data Exchange (ETDEWEB)

    Kollmeier, Juna A.; Burns, Christopher R.; Thompson, Ian B.; Preston, George W.; Crane, Jeffrey D.; Madore, Barry F.; Morrell, Nidia; Prieto, José L.; Shectman, Stephen; Simon, Joshua D.; Villanueva, Edward [Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Szczygieł, Dorota M.; Gould, Andrew [Department of Astronomy, The Ohio State University, 4051 McPherson Laboratory, Columbus, OH 43210 (United States); Sneden, Christopher [Department of Astronomy, University of Texas at Austin, TX 78712 (United States); Dong, Subo [Institute for Advanced Study, 500 Einstein Drive, Princeton, NJ 08540 (United States)

    2013-09-20

    We present the first definitive measurement of the absolute magnitude of RR Lyrae c-type variable stars (RRc) determined purely from statistical parallax. We use a sample of 242 RRc variables selected from the All Sky Automated Survey for which high-quality light curves, photometry, and proper motions are available. We obtain high-resolution echelle spectra for these objects to determine radial velocities and abundances as part of the Carnegie RR Lyrae Survey. We find that M{sub V,RRc} = 0.59 ± 0.10 at a mean metallicity of [Fe/H] = –1.59. This is to be compared with previous estimates for RRab stars (M{sub V,RRab} = 0.76 ± 0.12) and the only direct measurement of an RRc absolute magnitude (RZ Cephei, M{sub V,RRc} = 0.27 ± 0.17). We find the bulk velocity of the halo relative to the Sun to be (W{sub π}, W{sub θ}, W{sub z} ) = (12.0, –209.9, 3.0) km s{sup –1} in the radial, rotational, and vertical directions with dispersions (σ{sub W{sub π}},σ{sub W{sub θ}},σ{sub W{sub z}}) = (150.4, 106.1, 96.0) km s{sup -1}. For the disk, we find (W{sub π}, W{sub θ}, W{sub z} ) = (13.0, –42.0, –27.3) km s{sup –1} relative to the Sun with dispersions (σ{sub W{sub π}},σ{sub W{sub θ}},σ{sub W{sub z}}) = (67.7,59.2,54.9) km s{sup -1}. Finally, as a byproduct of our statistical framework, we are able to demonstrate that UCAC2 proper-motion errors are significantly overestimated as verified by UCAC4.

  2. Is Fish Response related to Velocity and Turbulence Magnitudes? (Invited)

    Science.gov (United States)

    Wilson, C. A.; Hockley, F. A.; Cable, J.

    2013-12-01

    Riverine fish are subject to heterogeneous velocities and turbulence, and may use this to their advantage by selecting regions which balance energy expenditure for station holding whilst maximising energy gain through feeding opportunities. This study investigated microhabitat selection by guppies (Poecilia reticulata) in terms of the three-dimensional velocity structure generated by idealised boulders in an experimental flume. Velocity and turbulence influenced intra-species variation in swimming behaviour with respect to size, sex and parasite intensity. With increasing body length, fish swam further and more frequently between boulder regions. Larger guppies spent more time in the high velocity and low turbulence region, whereas smaller guppies preferred the low velocity and high shear stress region directly behind the boulders. Male guppies selected the region of low velocity, indicating a possible reduced swimming ability due to hydrodynamic drag imposed by their fins. With increasing parasite (Gyrodactylus turnbulli) burden, fish preferentially selected the region of moderate velocity which had the lowest bulk measure of turbulence of all regions and was also the most spatially homogeneous velocity and turbulence region. Overall the least amount of time was spent in the recirculation zone which had the highest magnitude of shear stresses and mean vertical turbulent length scale to fish length ratio. Shear stresses were a factor of two greater than in the most frequented moderate velocity region, while mean vertical turbulent length scale to fish length ratio were six times greater. Indeed the mean longitudinal turbulent scale was 2-6 times greater than the fish length in all regions. While it is impossible to discriminate between these two turbulence parameters (shear stress and turbulent length to fish length ratio) in influencing the fish preference, our study infers that there is a bias towards fish spending more time in a region where both the bulk

  3. First measurement of σ8 using supernova magnitudes only

    Science.gov (United States)

    Castro, Tiago; Quartin, Miguel

    2014-09-01

    A method was recently proposed which allows the conversion of the weak-lensing effects in the Type Ia supernova (SNeIa) Hubble diagram from noise into signal. Such signal is sensitive to the growth of structure in the universe, and in particular can be used as a measurement of σ8 independently from more traditional methods such as those based on the cosmic microwave background, cosmic shear or cluster abundance. We extend here that analysis to allow for intrinsic non-Gaussianities in the supernova probability distribution function, and discuss how this can be best modelled using the Bayes factor. Although it was shown that a precise measurement of σ8 requires ˜105 SNeIa, current data already allow an important proof of principle. In particular, we make use of the 706 supernovae with z ≤ 0.9 of the recent Joint Lightcurve Analysis catalogue and show that a simple treatment of intrinsic non-Gaussianities with a couple of nuisance parameters is enough for our method to yield the values σ _8 = 0.84^{+0.28}_{-0.65} or σ8 < 1.45 at a 2σ confidence level. This result is consistent with mock simulations and it is also in agreement with independent measurements and presents the first ever measurement of σ8 using SNeIa magnitudes alone.

  4. THE AGE OF ELLIPTICALS AND THE COLOR-MAGNITUDE RELATION

    International Nuclear Information System (INIS)

    Schombert, James; Rakos, Karl

    2009-01-01

    Using new narrowband color observations of early-type galaxies in clusters, we reconstruct the color-magnitude relation (CMR) with a higher degree of accuracy than previous work. We then use the spectroscopically determined ages and metallicities from three samples, combined with multimetallicity spectral energy distribution models, to compare predicted colors for galaxies with young ages (less than 8 Gyr) with the known CMR. We find that the CMR cannot by reproduced by the spectroscopically determined ages and metallicities in any of the samples despite the high internal accuracies to the spectroscopic indices. In contrast, using only the (Fe) index to determine [Fe/H], and assuming a mean age of 12 Gyr for a galaxy's stellar population, we derive colors that exactly match not only the color zero point of the CMR but also its slope. We consider the source of young age estimates, the Hβ index, and examine the conflict between red continuum colors and large Hβ values in galaxy spectra. We conclude that our current understanding of stellar populations is insufficient to correctly interpret Hβ values.

  5. Magnitude Squared of Coherence to Detect Imaginary Movement

    Directory of Open Access Journals (Sweden)

    Sady Antônio Santos Filho

    2009-01-01

    Full Text Available This work investigates the Magnitude Squared of Coherence (MSC for detection of Event Related Potentials (ERPs related to left-hand index finger movement. Initially, ERP presence was examined in different brain areas. To accomplish that, 20 EEG channels were used, positioned according to the 10–20 international system. The grand average, resulting from 10 normal subjects showed, as expected, responses at frontal, central, and parietal areas, particularly evident at the central area (C3, C4, Cz. The MSC, applied to movement imagination related EEG signals, detected a consistent response in frequencies around 0.3–1 Hz (delta band, mainly at central area (C3, Cz, and C4. Ability differences in control imagination among subjects produced different detection performance. Some subjects needed up to 45 events for a detectable response, while for some others only 10 events proved sufficient. Some subjects also required two or three experimental sessions in order to achieve detectable responses. For one subject, response detection was not possible at all. However, due to brain plasticity, it is plausible to expect that training sessions (to practice movement imagination improve signal-noise ratio and lead to better detection using MSC. Results are sufficiently encouraging as to suggest further exploration of MSC for future BCI application.

  6. Size matters: Perceived depth magnitude varies with stimulus height.

    Science.gov (United States)

    Tsirlin, Inna; Wilcox, Laurie M; Allison, Robert S

    2016-06-01

    Both the upper and lower disparity limits for stereopsis vary with the size of the targets. Recently, Tsirlin, Wilcox, and Allison (2012) suggested that perceived depth magnitude from stereopsis might also depend on the vertical extent of a stimulus. To test this hypothesis we compared apparent depth in small discs to depth in long bars with equivalent width and disparity. We used three estimation techniques: a virtual ruler, a touch-sensor (for haptic estimates) and a disparity probe. We found that depth estimates were significantly larger for the bar stimuli than for the disc stimuli for all methods of estimation and different configurations. In a second experiment, we measured perceived depth as a function of the height of the bar and the radius of the disc. Perceived depth increased with increasing bar height and disc radius suggesting that disparity is integrated along the vertical edges. We discuss size-disparity correlation and inter-neural excitatory connections as potential mechanisms that could account for these results. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Properties of the Magnitude Terms of Orthogonal Scaling Functions.

    Science.gov (United States)

    Tay, Peter C; Havlicek, Joseph P; Acton, Scott T; Hossack, John A

    2010-09-01

    The spectrum of the convolution of two continuous functions can be determined as the continuous Fourier transform of the cross-correlation function. The same can be said about the spectrum of the convolution of two infinite discrete sequences, which can be determined as the discrete time Fourier transform of the cross-correlation function of the two sequences. In current digital signal processing, the spectrum of the contiuous Fourier transform and the discrete time Fourier transform are approximately determined by numerical integration or by densely taking the discrete Fourier transform. It has been shown that all three transforms share many analogous properties. In this paper we will show another useful property of determining the spectrum terms of the convolution of two finite length sequences by determining the discrete Fourier transform of the modified cross-correlation function. In addition, two properties of the magnitude terms of orthogonal wavelet scaling functions are developed. These properties are used as constraints for an exhaustive search to determine an robust lower bound on conjoint localization of orthogonal scaling functions.

  8. Effects of magnitude, depth, and time on cellular seismology forecasts

    Science.gov (United States)

    Fisher, Steven Wolf

    This study finds that, in most cases analyzed to date, past seismicity tends to delineate zones where future earthquakes are likely to occur. Network seismicity catalogs for the New Madrid Seismic Zone (NMSZ), Australia (AUS), California (CA), and Alaska (AK) are analyzed using modified versions of the Cellular Seismology (CS) method of Kafka (2002, 2007). The percentage of later occurring earthquakes located near earlier occurring earthquakes typically exceeds the expected percentage for randomly distributed later occurring earthquakes, and the specific percentage is influenced by several variables, including magnitude, depth, time, and tectonic setting. At 33% map area coverage, hit percents are typically 85-95% in the NMSZ, 50-60% in AUS, 75-85% in CA, and 75-85% in AK. Statistical significance testing is performed on trials analyzing the same variables so that the overall regions can be compared, although some tests are inconclusive due to the small number of earthquake sample sizes. These results offer useful insights into understanding the capabilities and limits of CS studies, which can provide guidance for improving the seismicity-based components of seismic hazard assessments.

  9. [Early hypophosphataemia in at risk newborns. Frequency and magnitude].

    Science.gov (United States)

    Bustos Lozano, Gerardo; Hidalgo Romero, Álvaro; Melgar Bonis, Ana; Ureta Velasco, Noelia; Orbea Gallardo, Carlos; Pallás Alonso, Carmen

    2018-04-01

    To determine the frequency and magnitude of neonatal hypophosphataemia (32 weeks with weight

  10. Ultrasound Evaluation of the Magnitude of Pneumothorax: A New Concept

    Science.gov (United States)

    Sargsyan, Ashot E.; Nicolaou, S.; Kirkpatrick, A. W.; Hamilton, D. R.; Campbell, M. R,; Billica, R. D.; Dawson, D. L.; Williams, D. R.; Dulchavsky, S. A.

    2000-01-01

    Pneumothorax is commonly seen in trauma patients; the diagnosis is usually confirmed by radiography. Use of ultrasound for this purpose, in environments such as space flight and remote terrestrial areas where radiographic capabilities are absent, is being investigated by NASA. In this study, the ability of ultrasound to assess the magnitude of pneumothorax in a porcine model was evaluated. Sonography was performed on anesthetized pigs (avg. wt. 50 kg) in both ground-based laboratory (n = 5) and micro gravity conditions (0 g) aboard the KC-135 aircraft during parabolic flight (n = 4). Aliquots of air (50-1 OOcc) were introduced into the chest through a catheter to simulate pneumothorax. Results were video-recorded and digitized for later interpretation by radiologists. Several distinct sonographic patterns of partial lung sliding were noted, including the combination of a sliding zone with a still zone, and a "segmented" sliding zone. These "partial lung sliding" patterns exclude massive pneumothorax manifested by a complete separation of the lung from the parietal pleura. In 0 g, the sonographic picture was more diverse; 1 g differences between posterior and anterior aspects were diminished. CONCLUSIONS: Modest pneumothorax can be inferred by the ultrasound sign of "partial lung sliding". This finding, which increases the negative predictive value of thoracic ultrasound, may be attributed to intermittent pleural contact, small air spaces, or alterations in pleural lubricant. Further studies of these phenomena are warranted.

  11. Magnitude of income-related disparities in adverse perinatal outcomes.

    Science.gov (United States)

    Shankardass, Ketan; O'Campo, Patricia; Dodds, Linda; Fahey, John; Joseph, Ks; Morinis, Julia; Allen, Victoria M

    2014-03-04

    To assess and compare multiple measurements of socioeconomic position (SEP) in order to determine the relationship with adverse perinatal outcomes across various contexts. A birth registry, the Nova Scotia Atlee Perinatal Database, was confidentially linked to income tax and related information for the year in which delivery occurred. Multiple logistic regression was used to examine odds ratios between multiple indicators of SEP and multiple adverse perinatal outcomes in 117734 singleton births between 1988 and 2003. Models for after tax family income were also adjusted for neighborhood deprivation to gauge the relative magnitude of effects related to SEP at both levels. Effects of SEP were stratified by single- versus multiple-parent family composition, and by urban versus rural location of residence. The risk of small for gestational age and spontaneous preterm birth was higher across all the indicators of lower SEP, while risk for large for gestational age was lower across indicators of lower SEP. Higher risk of postneonatal death was demonstrated for several measures of lower SEP. Higher material deprivation in the neighborhood of residence was associated with increased risk for perinatal death, small for gestational age birth, and iatrogenic and spontaneous preterm birth. Family composition and urbanicity were shown to modify the association between income and some perinatal outcomes. This study highlights the importance of understanding the definitions of SEP and the mechanisms that lead to the association between income and poor perinatal outcomes, and broadening the types of SEP measures used in some cases.

  12. Floods in the United States: Magnitude and frequency

    Science.gov (United States)

    Jarvis, Clarence S.; ,

    1936-01-01

    From time immemorial floods have transformed beneficent river waters into a menace to humanity. Man's progress toward economic stability has been repeatedly halted or even thrown backward by the interruption of his efforts to make effective use of rivers and of valley lands. This handicap is not imposed by the destructiveness of large rivers alone, or of rivers in widely separated areas, for there are few if any streams, brooks, or rivulets that are not subject to flows beyond their channel capacities. Yet, though man for ages has suffered seriously from recurring floods, he has not been deterred from continuing to extend his activities in areas that are virtually foredoomed to flood damage.Today in the United States serious floods may occur in any section in any year, and even, in some regions, several times a year. Many of these floods leave behind them the tragedy of death and disease and of property irreparably damaged. The aggregate direct property damage caused by floods in this country has been estimated roughly to average $35,000,000 a year. In addition there are serious indirect and intangible losses of great but not precisely calculable magnitude.

  13. Low Magnitude Occupational Radiation Exposures Are They Safe or Unsafe

    International Nuclear Information System (INIS)

    Ravichandran, R.

    2013-01-01

    Man has always been exposed to ionizing radiation from natural sources and background exposure varies with the locations. No deleterious effects have been uniquely correlated, either they are not produced at low levels of exposure or their frequency is too low to be statistically observable. Direct source of information on radiation hazards in man is obviously based on follow up of population groups exposed to certain levels of radiation. Harmful effects of ionizing radiations are traced to documented exposures; for radiologists during 1920 s and 30 s, miners exposed to airborne radioactivity, workers in the radium industry, follow-up data of Japanese nuclear bomb survivors of Hiroshima and Nagasaki, the Marshallese accident in 1954, and the victims of the limited number of accidents at nuclear installations including Chernobyl. Mostly these information are from situations involving higher doses and dose rates. Ionizing radiations have been used extensively on the peaceful applications of atomic energy in general and medical applications in particular have shown to outweigh benefits over the risks. Personnel, low magnitude of exposures are encountered during routine work in handling radiation sources. In the light of present knowledge there is need to reassess the quantum of actual risk instead of projected risk based on long time models. The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) described models for dose-response relationships and micro-dosimetric arguments for defining low doses. The definition of low doses could also be based on direct observations in experimental or epidemiological studies. Through measurement of cell damage or death using human lymphocytes, linear and quadratic terms have been fitted the response and low doses have been judged to be 20-40 mSv. Data derived from epidemiological studies, mainly the atomic bomb survivors, suggests that for solid tumours and leukaemia, 200 mSv could be considered the

  14. Magnitude of Interfractional Vaginal Cuff Movement: Implications for External Irradiation

    International Nuclear Information System (INIS)

    Ma, Daniel J.; Michaletz-Lorenz, Martha; Goddu, S. Murty; Grigsby, Perry W.

    2012-01-01

    Purpose: To quantify the extent of interfractional vaginal cuff movement in patients receiving postoperative irradiation for cervical or endometrial cancer in the absence of bowel/bladder instruction. Methods and Materials: Eleven consecutive patients with cervical or endometrial cancer underwent placement of three gold seed fiducial markers in the vaginal cuff apex as part of standard of care before simulation. Patients subsequently underwent external irradiation and brachytherapy treatment based on institutional guidelines. Daily megavoltage CT imaging was performed during each external radiation treatment fraction. The daily positions of the vaginal apex fiducial markers were subsequently compared with the original position of the fiducial markers on the simulation CT. Composite dose–volume histograms were also created by summing daily target positions. Results: The average (± standard deviation) vaginal cuff movement throughout daily pelvic external radiotherapy when referenced to the simulation position was 16.2 ± 8.3 mm. The maximum vaginal cuff movement for any patient during treatment was 34.5 mm. In the axial plane the mean vaginal cuff movement was 12.9 ± 6.7 mm. The maximum vaginal cuff axial movement was 30.7 mm. In the craniocaudal axis the mean movement was 10.3 ± 7.6 mm, with a maximum movement of 27.0 mm. Probability of cuff excursion outside of the clinical target volume steadily dropped as margin size increased (53%, 26%, 4.2%, and 1.4% for 1.0, 1.5, 2.0, and 2.5 cm, respectively.) However, rectal and bladder doses steadily increased with larger margin sizes. Conclusions: The magnitude of vaginal cuff movement is highly patient specific and can impact target coverage in patients without bowel/bladder instructions at simulation. The use of vaginal cuff fiducials can help identify patients at risk for target volume excursion.

  15. Landslide scaling and magnitude-frequency distribution (Invited)

    Science.gov (United States)

    Stark, C. P.; Guzzetti, F.

    2009-12-01

    Landslide-driven erosion is controlled by the scale and frequency of slope failures and by the consequent fluxes of debris off the hillslopes. Here I focus on the magnitude-frequency part of the process and develop a theory of initial slope failure and debris mobilization that reproduces the heavy-tailed distributions (PDFs) observed for landslide source areas and volumes. Landslide rupture propagation is treated as a quasi-static, non-inertial process of simplified elastoplastic deformation with strain weakening; debris runout is not considered. The model tracks the stochastically evolving imbalance of frictional, cohesive, and body forces across a failing slope, and uses safety-factor concepts to convert the evolving imbalance into a series of incremental rupture growth or arrest probabilities. A single rupture is simulated with a sequence of weighted ``coin tosses'' with weights set by the growth probabilities. Slope failure treated in this stochastic way is a survival process that generates asymptotically power-law-tail PDFs of area and volume for rock and debris slides; predicted scaling exponents are consistent with analyses of landslide inventories. The primary control on the shape of the model PDFs is the relative importance of cohesion over friction in setting slope stability: the scaling of smaller, shallower failures, and the size of the most common landslide volumes, are the result of the low cohesion of soil and regolith, whereas the negative power-law tail scaling for larger failures is tied to the greater cohesion of bedrock. The debris budget may be dominated by small or large landslides depending on the scaling of both the PDF and of the depth-length relation. I will present new model results that confirm the hypothesis that depth-length scaling is linear. Model PDF of landslide volumes.

  16. Magnitude of Anemia at Discharge Increases 30-Day Hospital Readmissions.

    Science.gov (United States)

    Koch, Colleen G; Li, Liang; Sun, Zhiyuan; Hixson, Eric D; Tang, Anne; Chagin, Kevin; Kattan, Michael; Phillips, Shannon C; Blackstone, Eugene H; Henderson, J Michael

    2017-12-01

    Anemia during hospitalization is associated with poor health outcomes. Does anemia at discharge place patients at risk for hospital readmission within 30 days of discharge? Our objectives were to examine the prevalence and magnitude of anemia at hospital discharge and determine whether anemia at discharge was associated with 30-day readmissions among a cohort of hospitalizations in a single health care system. From January 1, 2009, to August 31, 2011, there were 152,757 eligible hospitalizations within a single health care system. The endpoint was any hospitalization within 30 days of discharge. The University HealthSystem Consortium's clinical database was used for demographics and comorbidities; hemoglobin values are from the hospitals' electronic medical records, and readmission status was obtained from the University HealthSystem Consortium administrative data systems. Mild anemia was defined as hemoglobin of greater than 11 to less than 12 g/dl in women and greater than 11 to less than 13 g/dl in men; moderate, greater than 9 to less than or equal to 11 g/dl; and severe, less than or equal to 9 g/dl. Logistic regression was used to assess the association of anemia and 30-day readmissions adjusted for demographics, comorbidity, and hospitalization type. Among 152,757 hospitalizations, 72% of patients were discharged with anemia: 31,903 (21%), mild; 52,971 (35%), moderate; and 25,522 (17%), severe. Discharge anemia was associated with severity-dependent increased odds for 30-day hospital readmission compared with those without anemia: for mild anemia, 1.74 (1.65-1.82); moderate anemia, 2.76 (2.64-2.89); and severe anemia, 3.47 (3.30-3.65), P < 0.001. Anemia at discharge is associated with a severity-dependent increased risk for 30-day readmission. A strategy focusing on anemia treatment care paths during index hospitalization offers an opportunity to influence subsequent readmissions.

  17. The magnitude of syphilis: from prevalence to vertical transmission

    Directory of Open Access Journals (Sweden)

    Luciane Rodrigues Pedreira de Cerqueira

    2017-12-01

    Full Text Available ABSTRACT Introduction: In 2013, the World Health Organization (WHO reported that 1.9 million pregnant women were infected with syphilis worldwide, of which 66.5% had adverse fetal effects in cases of untreated syphilis. Congenital syphilis contributes significantly to infant mortality, accounting for 305,000 perinatal deaths worldwide annually. Aim: To estimate the prevalence of syphilis in parturients, the incidence of congenital syphilis and the vertical transmission rate. Material and methods: a cross-sectional study with data collected from 2041 parturients who had undergone treatment between 2012 and 2014 in the maternity section of the Pedro Ernesto Hospital of the State University of Rio de Janeiro, in the metropolitan area of Rio de Janeiro. The inclusion criterion was positive VDRL and treponemal test in a hospital environment. Results: the prevalence of syphilis in pregnant women was 4.1% in 2012, 3.1% in 2013 and 5% in 2014, with official reporting of 15.6%, 25.0% and 48.1%, respectively. The incidence of congenital syphilis (CS was 22/1,000 in live births (LB in 2012; 17/1,000 LB in 2013 and 44.8/1,000 LB in 2014. CS underreporting during the period was 6.7%. Vertical transmission occurred in 65.8% of infants from infected mothers. It was concluded that, in 34.6% of the CS cases, maternal VDRL titers were = 1/4. Conclusion: Results demonstrate the magnitude of the disease, fragility of the reporting system in the assessment of the actual prevalence, impact on perinatal outcomes, and they are a warning about the real situation of syphilis, which is still underestimated in the State.

  18. The magnitude of syphilis: from prevalence to vertical transmission.

    Science.gov (United States)

    Cerqueira, Luciane Rodrigues Pedreira de; Monteiro, Denise L M; Taquette, Stella R; Rodrigues, Nádia C P; Trajano, Alexandre J B; Souza, Flavio Monteiro de; Araújo, Bianca De Melo

    2017-12-21

    In 2013, the World Health Organization (WHO) reported that 1.9 million pregnant women were infected with syphilis worldwide, of which 66.5% had adverse fetal effects in cases of untreated syphilis. Congenital syphilis contributes significantly to infant mortality, accounting for 305,000 perinatal deaths worldwide annually. To estimate the prevalence of syphilis in parturients, the incidence of congenital syphilis and the vertical transmission rate. a cross-sectional study with data collected from 2041 parturients who had undergone treatment between 2012 and 2014 in the maternity section of the Pedro Ernesto Hospital of the State University of Rio de Janeiro, in the metropolitan area of Rio de Janeiro. The inclusion criterion was positive VDRL and treponemal test in a hospital environment. the prevalence of syphilis in pregnant women was 4.1% in 2012, 3.1% in 2013 and 5% in 2014, with official reporting of 15.6%, 25.0% and 48.1%, respectively. The incidence of congenital syphilis (CS) was 22/1,000 in live births (LB) in 2012; 17/1,000 LB in 2013 and 44.8/1,000 LB in 2014. CS underreporting during the period was 6.7%. Vertical transmission occurred in 65.8% of infants from infected mothers. It was concluded that, in 34.6% of the CS cases, maternal VDRL titers were = 1/4. Results demonstrate the magnitude of the disease, fragility of the reporting system in the assessment of the actual prevalence, impact on perinatal outcomes, and they are a warning about the real situation of syphilis, which is still underestimated in the State.

  19. The relationship between local and moment magnitude in Greece during the period 2008-2016

    Science.gov (United States)

    Konstantinou, K. I.; Melis, N. S.

    2018-03-01

    We perform a systematic comparison between local and moment magnitudes in Greece for the period 2008-2016 when both magnitudes have been determined using waveform data recorded by the Hellenic Unified Seismic Network (HUSN). Differences between the two magnitudes scales on average do not exceed ± 0.2 units as has been found in other regions worldwide. A recalculation of local magnitude using magnitude residuals for each HUSN station shows that station site conditions have very little influence on the difference between local and moment magnitude. It is therefore more likely that wave propagation effects and in rare cases, anomalous source properties are dominant factors in shaping this difference. General orthogonal regression is applied to the whole dataset and also to subsets covering different areas of Greece or different time period to calibrate the one magnitude scale against the other using a linear model. The resulting relationships differ very little, suggesting that there is no significant regional/temporal variation between local and moment magnitudes. While these relationships predict that local magnitude is very close to moment magnitude if both are determined using HUSN data, the comparison with Global CMT moment magnitude (with M w in the range 4.5-6.2) shows that it is larger than local magnitude by 0.18 units. These results are particularly important for converting local magnitudes to equivalent moment magnitudes and thus homogenize the Greek earthquake catalog.

  20. The cause of larger local magnitude (Mj) in western Japan

    Science.gov (United States)

    Kawamoto, H.; Furumura, T.

    2017-12-01

    The local magnitude of the Japan Meteorological Agency (JMA) scale (Mj) in Japan sometimes show a significant discrepancy between Mw. The Mj is calculated using the amplitude of the horizontal component of ground displacement recorded by seismometers with the natural period of T0=5 s using Katsumata et al. (2004). A typical example of such a discrepancy in estimating Mj was an overestimation of the 2000 Western Tottori earthquake (Mj=7.3, Mw=6.7; hereafter referred to as event T). In this study, we examined the discrepancy between Mj and Mw for recent large earthquakes occurring in Japan.We found that the most earthquakes with larger Mj (>Mw) occur in western Japan while the earthquakes in northern Japan show reasonable Mj (=Mw). To understand the cause of such larger Mj for western Japan earthquakes we examined the strong motion record from the K-NET and KiK-net network for the event T and other earthquakes for reference. The observed ground displacement record from the event T shows a distinctive Love wave packet in tangential motion with a dominant period of about T=5 s which propagates long distances without showing strong dispersions. On the other hand, the ground motions from the earthquakes in northeastern Japan do not have such surface wave packet, and attenuation of ground motion is significant. Therefore, the overestimation of the Mj for earthquakes in western Japan may be attributed to efficient generation and propagation properties of Love wave probably relating to the crustal structure of western Japan. To explain this, we then conducted a numerical simulation of seismic wave propagation using 3D sedimentary layer model (JIVSM; Koketsu et al., 2012) and the source model of the event T. The result demonstrated the efficient generation of Love wave from the shallow strike-slip source which propagates long distances in western Japan without significant dispersions. On the other hand, the generation of surface wave was not so efficient when using a

  1. Empirical Global Relations Converting M S and m b to Moment Magnitude

    Science.gov (United States)

    Scordilis, E. M.

    2006-04-01

    The existence of several magnitude scales used by seismological centers all over the world and the compilation of earthquake catalogs by many authors have rendered globally valid relations connecting magnitude scales a necessity. This would allow the creation of a homogeneous global earthquake catalog, a useful tool for earthquake research. Of special interest is the definition of global relations converting different magnitude scales to the most reliable and useful scale of magnitude, the moment magnitude, M W. In order to accomplish this, a very large sample of data from international seismological sources (ISC, NEIC, HRVD, etc.) has been collected and processed. The magnitude scales tested against M W are the surface wave magnitude, M S, the body wave magnitude, m b, and the local magnitude, M L. The moment magnitudes adopted have been taken from the CMT solutions of HRVD and USGS. The data set used in this study contains 20,407 earthquakes, which occurred all over the world during the time period 1.1.1976-31.5.2003, for which moment magnitudes are available. It is shown that well-defined relations hold between M W and m b and M S and that these relations can be reliably used for compiling homogeneous, with respect to magnitude, earthquake catalogs.

  2. The Effects of Numerical Magnitude, Size, and Color Saturation on Perceived Interval Duration

    Science.gov (United States)

    Alards-Tomalin, Doug; Leboe-McGowan, Jason P.; Shaw, Joshua D. M.; Leboe-McGowan, Launa C.

    2014-01-01

    The relative magnitude (or intensity) of an event can have direct implications on timing estimation. Previous studies have found that greater magnitude stimuli are often reported as longer in duration than lesser magnitudes, including Arabic digits (Xuan, Zhang, He, & Chen, 2007). One explanation for these findings is that different…

  3. Fourier Magnitude-Based Privacy-Preserving Clustering on Time-Series Data

    Science.gov (United States)

    Kim, Hea-Suk; Moon, Yang-Sae

    Privacy-preserving clustering (PPC in short) is important in publishing sensitive time-series data. Previous PPC solutions, however, have a problem of not preserving distance orders or incurring privacy breach. To solve this problem, we propose a new PPC approach that exploits Fourier magnitudes of time-series. Our magnitude-based method does not cause privacy breach even though its techniques or related parameters are publicly revealed. Using magnitudes only, however, incurs the distance order problem, and we thus present magnitude selection strategies to preserve as many Euclidean distance orders as possible. Through extensive experiments, we showcase the superiority of our magnitude-based approach.

  4. Reinforcer magnitude and rate dependency: evaluation of resistance-to-change mechanisms.

    Science.gov (United States)

    Pinkston, Jonathan W; Ginsburg, Brett C; Lamb, Richard J

    2014-10-01

    Under many circumstances, reinforcer magnitude appears to modulate the rate-dependent effects of drugs such that when schedules arrange for relatively larger reinforcer magnitudes rate dependency is attenuated compared with behavior maintained by smaller magnitudes. The current literature on resistance to change suggests that increased reinforcer density strengthens operant behavior, and such strengthening effects appear to extend to the temporal control of behavior. As rate dependency may be understood as a loss of temporal control, the effects of reinforcer magnitude on rate dependency may be due to increased resistance to disruption of temporally controlled behavior. In the present experiments, pigeons earned different magnitudes of grain during signaled components of a multiple FI schedule. Three drugs, clonidine, haloperidol, and morphine, were examined. All three decreased overall rates of key pecking; however, only the effects of clonidine were attenuated as reinforcer magnitude increased. An analysis of within-interval performance found rate-dependent effects for clonidine and morphine; however, these effects were not modulated by reinforcer magnitude. In addition, we included prefeeding and extinction conditions, standard tests used to measure resistance to change. In general, rate-decreasing effects of prefeeding and extinction were attenuated by increasing reinforcer magnitudes. Rate-dependent analyses of prefeeding showed rate-dependency following those tests, but in no case were these effects modulated by reinforcer magnitude. The results suggest that a resistance-to-change interpretation of the effects of reinforcer magnitude on rate dependency is not viable.

  5. Self-stimulating rats combine subjective reward magnitude and subjective reward rate multiplicatively.

    Science.gov (United States)

    Leon, M I; Gallistel, C R

    1998-07-01

    For rats that bar pressed for intracranial electrical stimulation in a 2-lever matching paradigm with concurrent variable interval schedules of reward, the authors found that the time allocation ratio is based on a multiplicative combination of the ratio of subjective reward magnitudes and the ratio of the rates of reward. Multiplicative combining was observed in a range covering approximately 2 orders of magnitude in the ratio of the rates of reward from about 1:10 to 10:1) and an order of magnitude change in the size of rewards. After determining the relation between the pulse frequency of stimulation and subjective reward magnitude, the authors were able to predict from knowledge of the subjective magnitudes of the rewards and the obtained relative rates of reward the subject's time allocation ratio over a range in which it varied by more than 3 orders of magnitude.

  6. A design of calibration single star simulator with adjustable magnitude and optical spectrum output system

    Science.gov (United States)

    Hu, Guansheng; Zhang, Tao; Zhang, Xuan; Shi, Gentai; Bai, Haojie

    2018-03-01

    In order to achieve multi-color temperature and multi-magnitude output, magnitude and temperature can real-time adjust, a new type of calibration single star simulator was designed with adjustable magnitude and optical spectrum output in this article. xenon lamp and halogen tungsten lamp were used as light source. The control of spectrum band and temperature of star was realized with different multi-beam narrow band spectrum with light of varying intensity. When light source with different spectral characteristics and color temperature go into the magnitude regulator, the light energy attenuation were under control by adjusting the light luminosity. This method can completely satisfy the requirements of calibration single star simulator with adjustable magnitude and optical spectrum output in order to achieve the adjustable purpose of magnitude and spectrum.

  7. Quasi real-time estimation of the moment magnitude of large earthquake from static strain changes

    Science.gov (United States)

    Itaba, S.

    2016-12-01

    The 2011 Tohoku-Oki (off the Pacific coast of Tohoku) earthquake, of moment magnitude 9.0, was accompanied by large static strain changes (10-7), as measured by borehole strainmeters operated by the Geological Survey of Japan in the Tokai, Kii Peninsula, and Shikoku regions. A fault model for the earthquake on the boundary between the Pacific and North American plates, based on these borehole strainmeter data, yielded a moment magnitude of 8.7. On the other hand, based on the seismic wave, the prompt report of the magnitude which the Japan Meteorological Agency (JMA) announced just after earthquake occurrence was 7.9. Such geodetic moment magnitudes, derived from static strain changes, can be estimated almost as rapidly as determinations using seismic waves. I have to verify the validity of this method in some cases. In the case of this earthquake's largest aftershock, which occurred 29 minutes after the mainshock. The prompt report issued by JMA assigned this aftershock a magnitude of 7.3, whereas the moment magnitude derived from borehole strain data is 7.6, which is much closer to the actual moment magnitude of 7.7. In order to grasp the magnitude of a great earthquake earlier, several methods are now being suggested to reduce the earthquake disasters including tsunami. Our simple method of using static strain changes is one of the strong methods for rapid estimation of the magnitude of large earthquakes, and useful to improve the accuracy of Earthquake Early Warning.

  8. Fast Moment Magnitude Determination from P-wave Trains for Bucharest Rapid Early Warning System (BREWS)

    Science.gov (United States)

    Lizurek, Grzegorz; Marmureanu, Alexandru; Wiszniowski, Jan

    2017-03-01

    Bucharest, with a population of approximately 2 million people, has suffered damage from earthquakes in the Vrancea seismic zone, which is located about 170 km from Bucharest, at a depth of 80-200 km. Consequently, an earthquake early warning system (Bucharest Rapid earthquake Early Warning System or BREWS) was constructed to provide some warning about impending shaking from large earthquakes in the Vrancea zone. In order to provide quick estimates of magnitude, seismic moment was first determined from P-waves and then a moment magnitude was determined from the moment. However, this magnitude may not be consistent with previous estimates of magnitude from the Romanian Seismic Network. This paper introduces the algorithm using P-wave spectral levels and compares them with catalog estimates. The testing procedure used waveforms from about 90 events with catalog magnitudes from 3.5 to 5.4. Corrections to the P-wave determined magnitudes according to dominant intermediate depth events mechanism were tested for November 22, 2014, M5.6 and October 17, M6 events. The corrections worked well, but unveiled overestimation of the average magnitude result of about 0.2 magnitude unit in the case of shallow depth event ( H < 60 km). The P-wave spectral approach allows for the relatively fast estimates of magnitude for use in BREWS. The average correction taking into account the most common focal mechanism for radiation pattern coefficient may lead to overestimation of the magnitude for shallow events of about 0.2 magnitude unit. However, in case of events of intermediate depth of M6 the resulting M w is underestimated at about 0.1-0.2. We conclude that our P-wave spectral approach is sufficiently robust for the needs of BREWS for both shallow and intermediate depth events.

  9. Involvement of Working Memory in Longitudinal Development of Number-Magnitude Skills

    Science.gov (United States)

    Kolkman, Meijke E.; Kroesbergen, Evelyn H.; Leseman, Paul P. M.

    2014-01-01

    The ability to connect numbers and magnitudes is an important prerequisite for math learning, here referred to as number-magnitude skills. It has been proposed that working memory plays an important role in constructing these connections. The aim of the current study was to examine if working memory accounts for constructing these connections by…

  10. Relations of Different Types of Numerical Magnitude Representations to Each Other and to Mathematics Achievement

    Science.gov (United States)

    Fazio, Lisa K.; Bailey, Drew H.; Thompson, Clarissa A.; Siegler, Robert S.

    2014-01-01

    We examined relations between symbolic and non-symbolic numerical magnitude representations, between whole number and fraction representations, and between these representations and overall mathematics achievement in fifth graders. Fraction and whole number symbolic and non-symbolic numerical magnitude understandings were measured using both…

  11. Developing Deaf Students Fraction Skills Requires Understanding Magnitude and Whole Number Division

    Science.gov (United States)

    Mousley, Keith; Kelly, Ronald R.

    2018-01-01

    Research has shown that fraction magnitude and whole number division are important precursors to learning and understanding fractions. Deaf and hard-of-hearing (DHH) students are consistently challenged with learning fractions from K-12 through college. Sixty DHH college students were tested for both their understanding of magnitude between two…

  12. Nonsymbolic and symbolic magnitude comparison skills as longitudinal predictors of mathematical achievement

    NARCIS (Netherlands)

    Xenidou-Dervou, I.; Molenaar, D.; Ansari, D.; van der Schoot, M.; van Lieshout, E.C.D.M.

    What developmental roles do nonsymbolic (e.g., dot arrays) and symbolic (i.e., Arabic numerals) magnitude comparison skills play in children's mathematics? We assessed a large sample in kindergarten, grade 1 and 2 on two well-known nonsymbolic and symbolic magnitude comparison measures. We also

  13. Representations of Numerical and Non-Numerical Magnitude Both Contribute to Mathematical Competence in Children

    Science.gov (United States)

    Lourenco, Stella F.; Bonny, Justin W.

    2017-01-01

    A growing body of evidence suggests that non-symbolic representations of number, which humans share with nonhuman animals, are functionally related to uniquely human mathematical thought. Other research suggesting that numerical and non-numerical magnitudes not only share analog format but also form part of a general magnitude system raises…

  14. ESMO-Magnitude of Clinical Benefit Scale version 1.1

    NARCIS (Netherlands)

    Cherny, N. I.; Dafni, U.; Bogaerts, J.; Latino, N. J.; Pentheroudakis, G.; Douillard, J. -Y.; Tabernero, J.; Zielinski, C.; Piccart, M. J.; de Vries, E. G. E.

    2017-01-01

    Background: The ESMO Magnitude of Clinical Benefit Scale (ESMO-MCBS) version 1.0 (v1.0) was published in May 2015 and was the first version of a validated and reproducible tool to assess the magnitude of clinical benefit from new cancer therapies. The ESMO-MCBS was designed to be a dynamic tool with

  15. Constraining the magnitude of the largest event in a foreshock-main shock-aftershock sequence

    Science.gov (United States)

    Shcherbakov, Robert; Zhuang, Jiancang; Ogata, Yosihiko

    2018-01-01

    Extreme value statistics and Bayesian methods are used to constrain the magnitudes of the largest expected earthquakes in a sequence governed by the parametric time-dependent occurrence rate and frequency-magnitude statistics. The Bayesian predictive distribution for the magnitude of the largest event in a sequence is derived. Two types of sequences are considered, that is, the classical aftershock sequences generated by large main shocks and the aftershocks generated by large foreshocks preceding a main shock. For the former sequences, the early aftershocks during a training time interval are used to constrain the magnitude of the future extreme event during the forecasting time interval. For the latter sequences, the earthquakes preceding the main shock are used to constrain the magnitudes of the subsequent extreme events including the main shock. The analysis is applied retrospectively to past prominent earthquake sequences.

  16. Spatiotemporal evolution of the completeness magnitude of the Icelandic earthquake catalogue from 1991 to 2013

    Science.gov (United States)

    Panzera, Francesco; Mignan, Arnaud; Vogfjörð, Kristin S.

    2017-07-01

    In 1991, a digital seismic monitoring network was installed in Iceland with a digital seismic system and automatic operation. After 20 years of operation, we explore for the first time its nationwide performance by analysing the spatiotemporal variations of the completeness magnitude. We use the Bayesian magnitude of completeness (BMC) method that combines local completeness magnitude observations with prior information based on the density of seismic stations. Additionally, we test the impact of earthquake location uncertainties on the BMC results, by filtering the catalogue using a multivariate analysis that identifies outliers in the hypocentre error distribution. We find that the entire North-to-South active rift zone shows a relatively low magnitude of completeness Mc in the range 0.5-1.0, highlighting the ability of the Icelandic network to detect small earthquakes. This work also demonstrates the influence of earthquake location uncertainties on the spatiotemporal magnitude of completeness analysis.

  17. Missing texture reconstruction method based on error reduction algorithm using Fourier transform magnitude estimation scheme.

    Science.gov (United States)

    Ogawa, Takahiro; Haseyama, Miki

    2013-03-01

    A missing texture reconstruction method based on an error reduction (ER) algorithm, including a novel estimation scheme of Fourier transform magnitudes is presented in this brief. In our method, Fourier transform magnitude is estimated for a target patch including missing areas, and the missing intensities are estimated by retrieving its phase based on the ER algorithm. Specifically, by monitoring errors converged in the ER algorithm, known patches whose Fourier transform magnitudes are similar to that of the target patch are selected from the target image. In the second approach, the Fourier transform magnitude of the target patch is estimated from those of the selected known patches and their corresponding errors. Consequently, by using the ER algorithm, we can estimate both the Fourier transform magnitudes and phases to reconstruct the missing areas.

  18. Joint maximum-likelihood magnitudes of presumed underground nuclear test explosions

    Science.gov (United States)

    Peacock, Sheila; Douglas, Alan; Bowers, David

    2017-08-01

    Body-wave magnitudes (mb) of 606 seismic disturbances caused by presumed underground nuclear test explosions at specific test sites between 1964 and 1996 have been derived from station amplitudes collected by the International Seismological Centre (ISC), by a joint inversion for mb and station-specific magnitude corrections. A maximum-likelihood method was used to reduce the upward bias of network mean magnitudes caused by data censoring, where arrivals at stations that do not report arrivals are assumed to be hidden by the ambient noise at the time. Threshold noise levels at each station were derived from the ISC amplitudes using the method of Kelly and Lacoss, which fits to the observed magnitude-frequency distribution a Gutenberg-Richter exponential decay truncated at low magnitudes by an error function representing the low-magnitude threshold of the station. The joint maximum-likelihood inversion is applied to arrivals from the sites: Semipalatinsk (Kazakhstan) and Novaya Zemlya, former Soviet Union; Singer (Lop Nor), China; Mururoa and Fangataufa, French Polynesia; and Nevada, USA. At sites where eight or more arrivals could be used to derive magnitudes and station terms for 25 or more explosions (Nevada, Semipalatinsk and Mururoa), the resulting magnitudes and station terms were fixed and a second inversion carried out to derive magnitudes for additional explosions with three or more arrivals. 93 more magnitudes were thus derived. During processing for station thresholds, many stations were rejected for sparsity of data, obvious errors in reported amplitude, or great departure of the reported amplitude-frequency distribution from the expected left-truncated exponential decay. Abrupt changes in monthly mean amplitude at a station apparently coincide with changes in recording equipment and/or analysis method at the station.

  19. Earthquake of Saint-Hilaire-de-Voust (Vendee) from February 12, 2018 (3h08 TU), Magnitude = 4,8 (Local Magnitude - CEA)

    International Nuclear Information System (INIS)

    Cushing, Edward; Provost, Ludmila

    2018-01-01

    A 3.9-4.0 magnitude superficial earthquake occurred at Saint-Hilaire-de-Voust (Vendee, France) on February 12, 2018 (3h08 TU). This brief note reviews, first, the historical and present day seismicity of the Armorican region, and then analyses the earthquake impact on the closest nuclear facilities (Pouzauges industrial irradiation facility, Chinon and Civaux NPPs)

  20. Seismic experience in power and industrial facilities as it relates to small magnitude earthquakes

    International Nuclear Information System (INIS)

    Swan, S.W.; Horstman, N.G.

    1987-01-01

    The data base on the performance of power and industrial facilities in small magnitude earthquakes (M = 4.0 - 5.5) is potentially very large. In California alone many earthquakes in this magnitude range occur every year, often near industrial areas. In 1986 for example, in northern California alone, there were 76 earthquakes between Richter magnitude 4.0 and 5.5. Experience has shown that the effects of small magnitude earthquakes are seldom significant to well-engineered facilities. (The term well-engineered is here defined to include most modern industrial installations, as well as power plants and substations.) Therefore detailed investigations of small magnitude earthquakes are normally not considered worthwhile. The purpose of this paper is to review the tendency toward seismic damage of equipment installations representative of nuclear power plant safety systems. Estimates are made of the thresholds of seismic damage to certain types of equipment in terms of conventional means of measuring the damage potential of an earthquake. The objective is to define thresholds of damage that can be correlated with Richter magnitude. In this manner an earthquake magnitude might be chosen below which damage to nuclear plant safety systems is not considered credible

  1. An evolutionary approach to real-time moment magnitude estimation via inversion of displacement spectra

    Science.gov (United States)

    Caprio, M.; Lancieri, M.; Cua, G. B.; Zollo, A.; Wiemer, S.

    2011-01-01

    We present an evolutionary approach for magnitude estimation for earthquake early warning based on real-time inversion of displacement spectra. The Spectrum Inversion (SI) method estimates magnitude and its uncertainty by inferring the shape of the entire displacement spectral curve based on the part of the spectra constrained by available data. The method consists of two components: 1) estimating seismic moment by finding the low frequency plateau Ω0, the corner frequency fc and attenuation factor (Q) that best fit the observed displacement spectra assuming a Brune ω2 model, and 2) estimating magnitude and its uncertainty based on the estimate of seismic moment. A novel characteristic of this method is that is does not rely on empirically derived relationships, but rather involves direct estimation of quantities related to the moment magnitude. SI magnitude and uncertainty estimates are updated each second following the initial P detection. We tested the SI approach on broadband and strong motion waveforms data from 158 Southern California events, and 25 Japanese events for a combined magnitude range of 3 ≤ M ≤ 7. Based on the performance evaluated on this dataset, the SI approach can potentially provide stable estimates of magnitude within 10 seconds from the initial earthquake detection.

  2. Development of magnitude processing in children with developmental dyscalculia: Space, time and number

    Directory of Open Access Journals (Sweden)

    Kenny eSkagerlund

    2014-06-01

    Full Text Available Developmental dyscalculia (DD is a learning disorder associated with impairments in a preverbal non-symbolic approximate number system (ANS pertaining to areas in and around the intraparietal sulcus (IPS. The current study sought to enhance our understanding of the developmental trajectory of the ANS and symbolic number processing skills, thereby getting insight into whether a deficit in the ANS precedes or is preceded by impaired symbolic and exact number processing. Recent work has also suggested that humans are endowed with a shared magnitude system (beyond the number domain in the brain. We therefore investigated whether children with DD demonstrated a general magnitude deficit, stemming from the proposed magnitude system, rather than a specific one limited to numerical quantity. Fourth graders with DD were compared to age-matched controls and a group of ability-matched second graders, on a range of magnitude processing tasks pertaining to space, time, and number. Children with DD displayed difficulties across all magnitude dimensions compared to age-matched peers and showed impaired ANS acuity compared to the younger, ability-matched control group, while exhibiting intact symbolic number processing. We conclude that (1 children with DD suffer from a general magnitude-processing deficit, (2 a shared magnitude system likely exists, and (3 a symbolic number-processing deficit in DD tends to be preceded by an ANS deficit.

  3. Development of magnitude processing in children with developmental dyscalculia: space, time, and number.

    Science.gov (United States)

    Skagerlund, Kenny; Träff, Ulf

    2014-01-01

    Developmental dyscalculia (DD) is a learning disorder associated with impairments in a preverbal non-symbolic approximate number system (ANS) pertaining to areas in and around the intraparietal sulcus (IPS). The current study sought to enhance our understanding of the developmental trajectory of the ANS and symbolic number processing skills, thereby getting insight into whether a deficit in the ANS precedes or is preceded by impaired symbolic and exact number processing. Recent work has also suggested that humans are endowed with a shared magnitude system (beyond the number domain) in the brain. We therefore investigated whether children with DD demonstrated a general magnitude deficit, stemming from the proposed magnitude system, rather than a specific one limited to numerical quantity. Fourth graders with DD were compared to age-matched controls and a group of ability-matched second graders, on a range of magnitude processing tasks pertaining to space, time, and number. Children with DD displayed difficulties across all magnitude dimensions compared to age-matched peers and showed impaired ANS acuity compared to the younger, ability-matched control group, while exhibiting intact symbolic number processing. We conclude that (1) children with DD suffer from a general magnitude-processing deficit, (2) a shared magnitude system likely exists, and (3) a symbolic number-processing deficit in DD tends to be preceded by an ANS deficit.

  4. Understanding the magnitude dependence of PGA and PGV in NGA-West 2 data

    Science.gov (United States)

    Baltay, Annemarie S.; Hanks, Thomas C.

    2014-01-01

    The Next Generation Attenuation‐West 2 (NGA‐West 2) 2014 ground‐motion prediction equations (GMPEs) model ground motions as a function of magnitude and distance, using empirically derived coefficients (e.g., Bozorgniaet al., 2014); as such, these GMPEs do not clearly employ earthquake source parameters beyond moment magnitude (M) and focal mechanism. To better understand the magnitude‐dependent trends in the GMPEs, we build a comprehensive earthquake source‐based model to explain the magnitude dependence of peak ground acceleration and peak ground velocity in the NGA‐West 2 ground‐motion databases and GMPEs. Our model employs existing models (Hanks and McGuire, 1981; Boore, 1983, 1986; Anderson and Hough, 1984) that incorporate a point‐source Brune model, including a constant stress drop and the high‐frequency attenuation parameter κ0, random vibration theory, and a finite‐fault assumption at the large magnitudes to describe the data from magnitudes 3 to 8. We partition this range into four different magnitude regions, each of which has different functional dependences on M. Use of the four magnitude partitions separately allows greater understanding of what happens in any one subrange, as well as the limiting conditions between the subranges. This model provides a remarkably good fit to the NGA data for magnitudes from 3magnitude data, for which the corner frequency is masked by the attenuation of high frequencies. That this simple, source‐based model matches the NGA‐West 2 GMPEs and data so well suggests that considerable simplicity underlies the parametrically complex NGA GMPEs.

  5. The Near-IR TRGB Magnitude and Distance Modulus to NGC 185

    Directory of Open Access Journals (Sweden)

    Y.-J. Sohn

    2008-09-01

    Full Text Available We determined values of distance modulus to nearby dwarf galaxy NGC 185 from the Tip of Red-Giant Branch (TRGB method. Apparent magnitudes of the TRGB are estimated from the near-infrared JHK luminosity functions (LFs of the resolved giant branch stars. Theoretical absolute magnitudes of the TRGB in near-infrared bands have been extracted from the Yonsei-Yale isochrones. The observed apparent and theoretical absolute magnitudes of the TRGB provide values of distance modulus to NGC 185 as (m - M.

  6. Magnitude, direction and location of the resultant dipole moment of the pig heart.

    Science.gov (United States)

    Hodgkin, B C; Nelson, C V; Angelakos, E T

    1976-04-01

    Vectorcardiograms were obtained from 50 young domestic pigs using the Nelson lead system. Compensation for body size and shape is achieved and the resultant dipole moment magnitude reflects heart size. A strong relationship was found between heart size and maximum magnitude. Dipole moment magnitude increased as four pigs increased from five to ten weeks of age. The dipole moment during QRS is considered in light of known pig heart excitation pattern. Dipole locations during QRS, calculated by computer solution of the Gabor-Nelson equations, were in agreement with heart location and excitation data.

  7. Empirical conversion between teleseismic magnitudes (mb and Ms) and moment magnitude (Mw) at the Global, Euro-Mediterranean and Italian scale

    Science.gov (United States)

    Lolli, B.; Gasperini, P.; Vannucci, G.

    2014-11-01

    We analysed the conversion problem between teleseismic magnitudes (Ms and mb) provided by the Seismological Bulletin of the International Seismological Centre and moment magnitudes (Mw) provided by online moment tensor (MT) catalogues using the chi-square general orthogonal regression method (CSQ) that, differently from the ordinary least-square regression method (OLS), accounts for the measurement errors of both the predictor and response variables. To account for the non-linearity of the relationships, we used two types of curvilinear models: (i) the exponential model (EXP), recently proposed by the authors of the Global Catalogue sponsored by the Global Earthquake Model (GEM) Foundation and (ii) a connected bilinear (CBL) model, similar to that proposed by Ekström & Dziewonski, where two different linear trends at low and high magnitudes are connected by an arc of circle that preserves the continuity of the function and of its first derivative at the connecting points. For Ms, we found that the regression curves computed for a global data set (GBL) are likely to be biased by the incompleteness of global MT catalogues for Mw <5.0-5.5. In fact, the GBL curves deviate significantly from a similar regression curve computed for a Euro-Mediterranean data set (MED) integrated with the data provided by two regional MT catalogues including many more events with Mw < 5.0-5.5. The GLB regression curves overestimate the Mw proxies computed from Ms up to 0.5 magnitude units. Hence for computing Mw proxies at the global scale of Ms ≤ 5.5, we suggest to adopt the coefficients obtained from the MED regression. The analysis of the frequency-magnitude relationship of the resulting Mw proxy catalogues confirms the validity of this choice as the behaviour of b­-value as a function of cut-off magnitude of the GBL data set is much more stable using such approach. The incompleteness of Mw's provided from MT global catalogues also affects the mb GBL data set but in this case the

  8. Moment magnitude, local magnitude and corner frequency of small earthquakes nucleating along a low angle normal fault in the Upper Tiber valley (Italy)

    Science.gov (United States)

    Munafo, I.; Malagnini, L.; Chiaraluce, L.; Valoroso, L.

    2015-12-01

    The relation between moment magnitude (MW) and local magnitude (ML) is still a debated issue (Bath, 1966, 1981; Ristau et al., 2003, 2005). Theoretical considerations and empirical observations show that, in the magnitude range between 3 and 5, MW and ML scale 1∶1. Whilst for smaller magnitudes this 1∶1 scaling breaks down (Bethmann et al. 2011). For accomplishing this task we analyzed the source parameters of about 1500 (30.000 waveforms) well-located small earthquakes occurred in the Upper Tiber Valley (Northern Apennines) in the range of -1.5≤ML≤3.8. In between these earthquakes there are 300 events repeatedly rupturing the same fault patch generally twice within a short time interval (less than 24 hours; Chiaraluce et al., 2007). We use high-resolution short period and broadband recordings acquired between 2010 and 2014 by 50 permanent seismic stations deployed to monitor the activity of a regional low angle normal fault (named Alto Tiberina fault, ATF) in the framework of The Alto Tiberina Near Fault Observatory project (TABOO; Chiaraluce et al., 2014). For this study the direct determination of MW for small earthquakes is essential but unfortunately the computation of MW for small earthquakes (MW < 3) is not a routine procedure in seismology. We apply the contributions of source, site, and crustal attenuation computed for this area in order to obtain precise spectral corrections to be used in the calculation of small earthquakes spectral plateaus. The aim of this analysis is to achieve moment magnitudes of small events through a procedure that uses our previously calibrated crustal attenuation parameters (geometrical spreading g(r), quality factor Q(f), and the residual parameter k) to correct for path effects. We determine the MW-ML relationships in two selected fault zones (on-fault and fault-hanging-wall) of the ATF by an orthogonal regression analysis providing a semi-automatic and robust procedure for moment magnitude determination within a

  9. Maximum credible earthquake (MCE) magnitude of structures affecting the Ujung Lemahabang site

    International Nuclear Information System (INIS)

    Soerjodibroto, M.

    1997-01-01

    This report analyse the geological structures in/around Muria Peninsula that might originating potential earthquake hazard toward the selected site for NPP, Ujung Lemahabang (ULA). Analysis was focused on the Lasem fault and AF-1/AF-4 offshore faults that are considered as the determinant structures affecting the seismicity of ULA (Nira, 1979, Newjec, 1994). Methods for estimating the MCE of the structures include maximum historical earthquake, and relationship between the length of the fault and the magnitude of earthquake originating from the known structure (Tocher, Iida, Matsuda, Wells and Coopersmith). The MCE magnitude estimating by these method for earthquake originating along the Lasem and AF-1/AF-4 faults vary from 2,1M to 7,0M. Comparison between the result of historical data and fault-magnitude relationship, however, suggest a MCE magnitude of Ms=7,0M for both fault zones. (author)

  10. Understanding volatility correlation behavior with a magnitude cross-correlation function

    Science.gov (United States)

    Jun, Woo Cheol; Oh, Gabjin; Kim, Seunghwan

    2006-06-01

    We propose an approach for analyzing the basic relation between correlation properties of the original signal and its magnitude fluctuations by decomposing the original signal into its positive and negative fluctuation components. We use this relation to understand the following phenomenon found in many naturally occurring time series: the magnitude of the signal exhibits long-range correlation, whereas the original signal is short-range correlated. The applications of our approach to heart rate variability signals and high-frequency foreign exchange rates reveal that the difference between the correlation properties of the original signal and its magnitude fluctuations is induced by the time organization structure of the correlation function between the magnitude fluctuations of positive and negative components. We show that this correlation function can be described well by a stretched-exponential function and is related to the nonlinearity and the multifractal structure of the signals.

  11. Magnitude and sign correlations in conductance fluctuations of horizontal oil water two-phase flow

    International Nuclear Information System (INIS)

    Zhu, L; Jin, N D; Gao, Z K; Zong, Y B; Zhai, L S; Wang, Z Y

    2012-01-01

    In experiment we firstly define five typical horizontal oil-water flow patterns. Then we introduce an approach for analyzing signals by decomposing the original signals increment into magnitude and sign series and exploring their scaling properties. We characterize the nonlinear and linear properties of horizontal oil-water two-phase flow, which relate to magnitude and sign series respectively. We find that the joint distribution of different scaling exponents can effectively identify flow patterns, and the detrended fluctuation analysis (DFA) on magnitude and sign series can represent typical horizontal oil-water two-phase flow dynamics characteristics. The results indicate that the magnitude and sign decomposition method can be a helpful tool for characterizing complex dynamics of horizontal oil-water two-phase flow.

  12. Methods and Magnitudes of Rapid Weight Loss in Judo Athletes Over Pre-Competition Periods

    Directory of Open Access Journals (Sweden)

    Kons Rafael Lima

    2017-06-01

    Full Text Available Purpose. The study aimed to analyse the methods and magnitudes of rapid weight loss (RWL in judo team members in distinct periods before the biggest state competition in Southern Brazil.

  13. The Development of the Mental Representations of the Magnitude of Fractions

    Science.gov (United States)

    Gabriel, Florence C.; Szucs, Denes; Content, Alain

    2013-01-01

    We investigated the development of the mental representation of the magnitude of fractions during the initial stages of fraction learning in grade 5, 6 and 7 children as well as in adults. We examined the activation of global fraction magnitude in a numerical comparison task and a matching task. There were global distance effects in the comparison task, but not in the matching task. This suggests that the activation of the global magnitude representation of fractions is not automatic in all tasks involving magnitude judgments. The slope of the global distance effect increased during early fraction learning and declined by adulthood, demonstrating that the development of the fraction global distance effect differs from that of the integer distance effect. PMID:24236169

  14. Has the magnitude of floods across the USA changed with global CO2 levels?

    Science.gov (United States)

    Hirsch, Robert M.; Ryberg, Karen R.

    2012-01-01

    Statistical relationships between annual floods at 200 long-term (85–127 years of record) streamgauges in the coterminous United States and the global mean carbon dioxide concentration (GMCO2) record are explored. The streamgauge locations are limited to those with little or no regulation or urban development. The coterminous US is divided into four large regions and stationary bootstrapping is used to evaluate if the patterns of these statistical associations are significantly different from what would be expected under the null hypothesis that flood magnitudes are independent of GMCO2. In none of the four regions defined in this study is there strong statistical evidence for flood magnitudes increasing with increasing GMCO2. One region, the southwest, showed a statistically significant negative relationship between GMCO2 and flood magnitudes. The statistical methods applied compensate both for the inter-site correlation of flood magnitudes and the shorter-term (up to a few decades) serial correlation of floods.

  15. The global magnitude-frequency relationship for large explosive volcanic eruptions

    Science.gov (United States)

    Rougier, Jonathan; Sparks, R. Stephen J.; Cashman, Katharine V.; Brown, Sarah K.

    2018-01-01

    For volcanoes, as for other natural hazards, the frequency of large events diminishes with their magnitude, as captured by the magnitude-frequency relationship. Assessing this relationship is valuable both for the insights it provides about volcanism, and for the practical challenge of risk management. We derive a global magnitude-frequency relationship for explosive volcanic eruptions of at least 300Mt of erupted mass (or M4.5). Our approach is essentially empirical, based on the eruptions recorded in the LaMEVE database. It differs from previous approaches mainly in our conservative treatment of magnitude-rounding and under-recording. Our estimate for the return period of 'super-eruptions' (1000Gt, or M8) is 17ka (95% CI: 5.2ka, 48ka), which is substantially shorter than previous estimates, indicating that volcanoes pose a larger risk to human civilisation than previously thought.

  16. Moment magnitude determination of local seismic events recorded at selected Polish seismic stations

    Science.gov (United States)

    Wiejacz, Paweł; Wiszniowski, Jan

    2006-03-01

    The paper presents the method of local magnitude determination used at Polish seismic stations to report events originating in one of the four regions of induced seismicity in Poland or its immediate vicinity. The method is based on recalculation of the seismic moment into magnitude, whereas the seismic moment is obtained from spectral analysis. The method has been introduced at Polish seismic stations in the late 1990s but as of yet had not been described in full because magnitude discrepancies have been found between the results of the individual stations. The authors have performed statistics of these differences, provide their explanation and calculate station corrections for each station and each event source region. The limitations of the method are also discussed. The method is found to be a good and reliable method of local magnitude determination provided the limitations are observed and station correction applied.

  17. Rapid estimation of the moment magnitude of large earthquake from static strain changes

    Science.gov (United States)

    Itaba, S.

    2014-12-01

    The 2011 off the Pacific coast of Tohoku earthquake, of moment magnitude (Mw) 9.0, occurred on March 11, 2011. Based on the seismic wave, the prompt report of the magnitude which the Japan Meteorological Agency announced just after earthquake occurrence was 7.9, and it was considerably smaller than an actual value. On the other hand, using nine borehole strainmeters of Geological Survey of Japan, AIST, we estimated a fault model with Mw 8.7 for the earthquake on the boundary between the Pacific and North American plates. This model can be estimated about seven minutes after the origin time, and five minute after wave arrival. In order to grasp the magnitude of a great earthquake earlier, several methods are now being suggested to reduce the earthquake disasters including tsunami (e.g., Ohta et al., 2012). Our simple method of using strain steps is one of the strong methods for rapid estimation of the magnitude of great earthquakes.

  18. Maximum credible earthquake (MCE) magnitude of structures affecting the Ujung Lemahabang site

    Energy Technology Data Exchange (ETDEWEB)

    Soerjodibroto, M [National Atomic Energy Agency, Jakarta (Indonesia)

    1997-03-01

    This report analyse the geological structures in/around Muria Peninsula that might originating potential earthquake hazard toward the selected site for NPP, Ujung Lemahabang (ULA). Analysis was focused on the Lasem fault and AF-1/AF-4 offshore faults that are considered as the determinant structures affecting the seismicity of ULA (Nira, 1979, Newjec, 1994). Methods for estimating the MCE of the structures include maximum historical earthquake, and relationship between the length of the fault and the magnitude of earthquake originating from the known structure (Tocher, Iida, Matsuda, Wells and Coopersmith). The MCE magnitude estimating by these method for earthquake originating along the Lasem and AF-1/AF-4 faults vary from 2,1M to 7,0M. Comparison between the result of historical data and fault-magnitude relationship, however, suggest a MCE magnitude of Ms=7,0M for both fault zones. (author)

  19. Mole Pi: Using New Technology to Teach the Magnitude of a Mole

    Science.gov (United States)

    Geyer, Michael J.

    2014-01-01

    A modified technique for demonstrating the magnitude of Avogadro's number using a new Raspberry Pi computer and the Python language is described. The technique also provides students the opportunity to review dimensional analysis.

  20. Differential item functioning magnitude and impact measures from item response theory models.

    Science.gov (United States)

    Kleinman, Marjorie; Teresi, Jeanne A

    2016-01-01

    Measures of magnitude and impact of differential item functioning (DIF) at the item and scale level, respectively are presented and reviewed in this paper. Most measures are based on item response theory models. Magnitude refers to item level effect sizes, whereas impact refers to differences between groups at the scale score level. Reviewed are magnitude measures based on group differences in the expected item scores and impact measures based on differences in the expected scale scores. The similarities among these indices are demonstrated. Various software packages are described that provide magnitude and impact measures, and new software presented that computes all of the available statistics conveniently in one program with explanations of their relationships to one another.

  1. Symbolic and non-symbolic number magnitude processing in children with developmental dyscalculia.

    Science.gov (United States)

    Castro Cañizares, Danilka; Reigosa Crespo, Vivian; González Alemañy, Eduardo

    2012-11-01

    The aim of this study was to evaluate if children with Developmental Dyscalculia (DD) exhibit a general deficit in magnitude representations or a specific deficit in the connection of symbolic representations with the corresponding analogous magnitudes. DD was diagnosed using a timed arithmetic task. The experimental magnitude comparison tasks were presented in non-symbolic and symbolic formats. DD and typically developing (TD) children showed similar numerical distance and size congruity effects. However, DD children performed significantly slower in the symbolic task. These results are consistent with the access deficit hypothesis, according to which DD children's deficits are caused by difficulties accessing magnitude information from numerical symbols rather than in processing numerosities per se.

  2. Understanding volatility correlation behavior with a magnitude cross-correlation function.

    Science.gov (United States)

    Jun, Woo Cheol; Oh, Gabjin; Kim, Seunghwan

    2006-06-01

    We propose an approach for analyzing the basic relation between correlation properties of the original signal and its magnitude fluctuations by decomposing the original signal into its positive and negative fluctuation components. We use this relation to understand the following phenomenon found in many naturally occurring time series: the magnitude of the signal exhibits long-range correlation, whereas the original signal is short-range correlated. The applications of our approach to heart rate variability signals and high-frequency foreign exchange rates reveal that the difference between the correlation properties of the original signal and its magnitude fluctuations is induced by the time organization structure of the correlation function between the magnitude fluctuations of positive and negative components. We show that this correlation function can be described well by a stretched-exponential function and is related to the nonlinearity and the multifractal structure of the signals.

  3. A local earthquake coda magnitude and its relation to duration, moment M sub O, and local Richter magnitude M sub L

    Science.gov (United States)

    Suteau, A. M.; Whitcomb, J. H.

    1977-01-01

    A relationship was found between the seismic moment, M sub O, of shallow local earthquakes and the total duration of the signal, t, in seconds, measured from the earthquakes origin time, assuming that the end of the coda is composed of backscattering surface waves due to lateral heterogenity in the shallow crust following Aki. Using the linear relationship between the logarithm of M sub O and the local Richter magnitude M sub L, a relationship between M sub L and t, was found. This relationship was used to calculate a coda magnitude M sub C which was compared to M sub L for Southern California earthquakes which occurred during the period from 1972 to 1975.

  4. The Great Recession: a comparison of recession magnitudes in Europe, USA and Japan

    OpenAIRE

    Mazurek, Jiří

    2013-01-01

    In this article recession magnitudes in Europe, the USA and Japan during the Great Recession are compared. The strongest recessions (of severe category) occurred in Latvia, Lithuania and Estonia, while recessions in Japan and the USA were significantly weaker. Even the strongest recession (in Latvia) was found smaller in its magnitude than the Great Depression 1929-1933 in the USA. Hence, comparisons of the Great Recession to the Great Depression in the literature are somewhat exaggerated.

  5. Do Indonesian Children's Experiences with Large Currency Units Facilitate Magnitude Estimation of Long Temporal Periods?

    Science.gov (United States)

    Cheek, Kim A.

    2017-08-01

    Ideas about temporal (and spatial) scale impact students' understanding across science disciplines. Learners have difficulty comprehending the long time periods associated with natural processes because they have no referent for the magnitudes involved. When people have a good "feel" for quantity, they estimate cardinal number magnitude linearly. Magnitude estimation errors can be explained by confusion about the structure of the decimal number system, particularly in terms of how powers of ten are related to one another. Indonesian children regularly use large currency units. This study investigated if they estimate long time periods accurately and if they estimate those time periods the same way they estimate analogous currency units. Thirty-nine children from a private International Baccalaureate school estimated temporal magnitudes up to 10,000,000,000 years in a two-part study. Artifacts children created were compared to theoretical model predictions previously used in number magnitude estimation studies as reported by Landy et al. (Cognitive Science 37:775-799, 2013). Over one third estimated the magnitude of time periods up to 10,000,000,000 years linearly, exceeding what would be expected based upon prior research with children this age who lack daily experience with large quantities. About half treated successive powers of ten as a count sequence instead of multiplicatively related when estimating magnitudes of time periods. Children generally estimated the magnitudes of long time periods and familiar, analogous currency units the same way. Implications for ways to improve the teaching and learning of this crosscutting concept/overarching idea are discussed.

  6. Reinforcement magnitude modulation of rate dependent effects in pigeons and rats.

    Science.gov (United States)

    Ginsburg, Brett C; Pinkston, Jonathan W; Lamb, R J

    2011-08-01

    Response rate can influence the behavioral effects of many drugs. Reinforcement magnitude may also influence drug effects. Further, reinforcement magnitude can influence rate-dependent effects. For example, in an earlier report, we showed that rate-dependent effects of two antidepressants depended on reinforcement magnitude. The ability of reinforcement magnitude to interact with rate-dependency has not been well characterized. It is not known whether our previous results are specific to antidepressants or generalize to other drug classes. Here, we further examine rate-magnitude interactions by studying effects of two stimulants (d-amphetamine [0.32-5.6 mg/kg] and cocaine [0.32-10 mg/kg]) and two sedatives (chlordiazepoxide [1.78-32 mg/kg] and pentobarbital [1.0-17.8 mg/kg]) in pigeons responding under a 3-component multiple fixed-interval (FI) 300-s schedule maintained by 2-, 4-, or 8-s of food access. We also examine the effects of d-amphetamine [0.32-3.2 mg/kg] and pentobarbital [1.8-10 mg/kg] in rats responding under a similar multiple FI300-s schedule maintained by 2- or 10- food pellet (45 mg) delivery. In pigeons, cocaine and, to a lesser extent, chlordiazepoxide exerted rate-dependent effects that were diminished by increasing durations of food access. The relationship was less apparent for pentobarbital, and not present for d-amphetamine. In rats, rate-dependent effects of pentobarbital and d-amphetamine were not modulated by reinforcement magnitude. In conclusion, some drugs appear to exert rate-dependent effect which are diminished when reinforcement magnitude is relatively high. Subsequent analysis of the rate-dependency data suggest the effects of reinforcement magnitude may be due to a diminution of drug-induced increases in low-rate behavior that occurs early in the fixed-interval. (c) 2011 APA, all rights reserved.

  7. Application of the extreme value approaches to the apparent magnitude distribution of the earthquakes

    Science.gov (United States)

    Tinti, S.; Mulargia, F.

    1985-03-01

    The apparent magnitude of an earthquake y is defined as the observed magnitude value and differs from the true magnitude m because of the experimental noise n. If f(m) is the density distribution of the magnitude m, and if g(n) is the density distribution of the error n, then the density distribution of y is simply computed by convolving f and g, i.e. h(y)=f*g. If the distinction between y and m is not realized, any statistical analysis based on the frequency-magnitude relation of the earthquake is bound to produce questionable results. In this paper we investigate the impact of the apparent magnitude idea on the statistical methods that study the earthquake distribution by taking into account only the largest (or extremal) earthquakes. We use two approaches: the Gumbel method based on Gumbel theory ( Gumbel, 1958), and the Poisson method introduced by Epstein and Lomnitz (1966). Both methods are concerned with the asymptotic properties of the magnitude distributions. Therefore, we study and compare the asymptotic behaviour of the distributions h(y) and f(m) under suitable hypotheses on the nature of the experimental noise. We investigate in detail two dinstinct cases: first, the two-side limited symmetrical noise, i.e. the noise that is bound to assume values inside a limited region, and second, the normal noise, i.e. the noise that is distributed according to a normal symmetric distribution. We further show that disregarding the noise generally leads to biased results and that, in the framework of the apparent magnitude, the Poisson approach preserves its usefulness, while the Gumbel method gives rise to a curious paradox.

  8. Examining pitch and numerical magnitude processing in congenital amusia: A quasi-experimental pilot study.

    Science.gov (United States)

    Nunes-Silva, Marilia; Moura, Ricardo; Lopes-Silva, Júlia Beatriz; Haase, Vitor Geraldi

    2016-08-01

    Congenital amusia is a developmental disorder associated with deficits in pitch height discrimination or in integrating pitch sequences into melodies. This quasi-experimental pilot study investigated whether there is an association between pitch and numerical processing deficits in congenital amusia. Since pitch height discrimination is considered a form of magnitude processing, we investigated whether individuals with amusia present an impairment in numerical magnitude processing, which would reflect damage to a generalized magnitude system. Alternatively, we investigated whether the numerical processing deficit would reflect a disconnection between nonsymbolic and symbolic number representations. This study was conducted with 11 adult individuals with congenital amusia and a control comparison group of 6 typically developing individuals. Participants performed nonsymbolic and symbolic magnitude comparisons and number line tasks. Results were available from previous testing using the Montreal Battery of Evaluation of Amusia (MBEA) and a pitch change detection task (PCD). Compared to the controls, individuals with amusia exhibited no significant differences in their performance on both the number line and the nonsymbolic magnitude tasks. Nevertheless, they showed significantly worse performance on the symbolic magnitude task. Moreover, individuals with congenital amusia, who presented worse performance in the Meter subtest, also presented less precise nonsymbolic numerical representation. The relationship between meter and nonsymbolic numerical discrimination could indicate a general ratio processing deficit. The finding of preserved nonsymbolic numerical magnitude discrimination and mental number line representations, with impaired symbolic number processing, in individuals with congenital amusia indicates that (a) pitch height and numerical magnitude processing may not share common neural representations, and (b) in addition to pitch processing, individuals with

  9. Developmental Dyscalculia and Automatic Magnitudes Processing: Investigating Interference Effects between Area and Perimeter

    Directory of Open Access Journals (Sweden)

    Hili Eidlin-Levy

    2017-12-01

    Full Text Available The relationship between numbers and other magnitudes has been extensively investigated in the scientific literature. Here, the objectives were to examine whether two continuous magnitudes, area and perimeter, are automatically processed and whether adults with developmental dyscalculia (DD are deficient in their ability to automatically process one or both of these magnitudes. Fifty-seven students (30 with DD and 27 with typical development performed a novel Stroop-like task requiring estimation of one aspect (area or perimeter while ignoring the other. In order to track possible changes in automaticity due to practice, we measured performance after initial and continuous exposure to stimuli. Similar to previous findings, current results show a significant group × congruency interaction, evident beyond exposure level or magnitude type. That is, the DD group systematically showed larger Stroop effects. However, analysis of each exposure period showed that during initial exposure to stimuli the DD group showed larger Stroop effects in the perimeter and not in the area task. In contrast, during continuous exposure to stimuli no triple interaction was evident. It is concluded that both magnitudes are automatically processed. Nevertheless, individuals with DD are deficient in inhibiting irrelevant magnitude information in general and, specifically, struggle to inhibit salient area information after initial exposure to a perimeter comparison task. Accordingly, the findings support the assumption that DD involves a deficiency in multiple cognitive components, which include domain-specific and domain-general cognitive functions.

  10. Selective interference of grasp and space representations with number magnitude and serial order processing.

    Science.gov (United States)

    van Dijck, Jean-Philippe; Fias, Wim; Andres, Michael

    2015-10-01

    It has been proposed that the metrics of space, time and other magnitudes relevant for action are coupled through a generalized magnitude system that also contribute to number representation. Several studies capitalized on stimulus-response compatibility effects to show that numbers map onto left-right representations and grasp representations as a function of their magnitude. However, the tasks typically used do not allow disentangling magnitude from serial order processing. Here, we devised a working memory (WM) task where participants had to remember random sequences of numbers and perform a precision/whole-hand grip (Experiment 1) or a uni-manual left/right button press (Experiment 2) in response to numbers presented during the retention interval. This task does allow differentiating the interference of number magnitude and serial order with each set of responses. Experiment 1 showed that precision grips were initiated faster than whole-hand grips in response to small numbers, irrespective of their serial position in WM. In contrast, Experiment 2 revealed an advantage of right over left button presses as serial position increased, without any influence of number magnitude. These findings demonstrate that grasping and left-right movements overlap with distinct dimensions of number processing. These findings are discussed in the light of different theories explaining the interactions between numbers, space and action.

  11. Developmental Dyscalculia and Automatic Magnitudes Processing: Investigating Interference Effects between Area and Perimeter.

    Science.gov (United States)

    Eidlin-Levy, Hili; Rubinsten, Orly

    2017-01-01

    The relationship between numbers and other magnitudes has been extensively investigated in the scientific literature. Here, the objectives were to examine whether two continuous magnitudes, area and perimeter, are automatically processed and whether adults with developmental dyscalculia (DD) are deficient in their ability to automatically process one or both of these magnitudes. Fifty-seven students (30 with DD and 27 with typical development) performed a novel Stroop-like task requiring estimation of one aspect (area or perimeter) while ignoring the other. In order to track possible changes in automaticity due to practice, we measured performance after initial and continuous exposure to stimuli. Similar to previous findings, current results show a significant group × congruency interaction, evident beyond exposure level or magnitude type. That is, the DD group systematically showed larger Stroop effects. However, analysis of each exposure period showed that during initial exposure to stimuli the DD group showed larger Stroop effects in the perimeter and not in the area task. In contrast, during continuous exposure to stimuli no triple interaction was evident. It is concluded that both magnitudes are automatically processed. Nevertheless, individuals with DD are deficient in inhibiting irrelevant magnitude information in general and, specifically, struggle to inhibit salient area information after initial exposure to a perimeter comparison task. Accordingly, the findings support the assumption that DD involves a deficiency in multiple cognitive components, which include domain-specific and domain-general cognitive functions.

  12. Moment Magnitude Calibration for the Eastern Mediterranean Region from Broadband Regional Coda Envelopes

    Energy Technology Data Exchange (ETDEWEB)

    Mayeda, K; Eken, T; Hofstetter, A; Turkelli, N; O' Boyle, J; Orgulu, G; Gok, R

    2003-07-17

    The following is an overview of results from ROA01-32 that focuses on an empirical method of calibrating stable seismic source moment-rate spectra derived from regional coda envelopes using broadband stations. The main goal was to develop a regional magnitude methodology that had the following properties: (1) it is tied to an absolute scale and is thus unbiased and transportable; (2) it can be tied seamlessly to the well-established teleseismic and regional catalogs; (3) it is applicable to small events using a sparse network of regional stations; (4) it is flexible enough to utilize S{sub n}-coda, L{sub g}-coda, or P-coda, whichever phase has the best signal-to-noise ratio. The results of this calibration yield source spectra and derived magnitudes that were more stable than any other direct-phase measure to date. Our empirical procedure accounted for all propagation, site, and S-to-coda transfer function effects. The resultant coda-derived moment-rate spectra were used to provide traditional band-limited magnitude (e.g., M{sub L}, m{sub b} etc.) as well as an unbiased, unsaturated magnitude (moment magnitude, M{sub w}) that is tied to a physical measure of earthquake size (i.e., seismic moment). We validated our results by comparing our coda-derived moment estimates with those obtained from long-period waveform modeling. We first tested and validated the method using events distributed along the Dead Sea Rift (e.g., Mayeda et al., 2003). Next, we tested the transportability of the method to earthquakes distributed across the entire country of Turkey and validated our results using seismic moments of over 50 events that had been previously waveform modeled using the method of Dreger and Helmberger, (1993). In both regions we demonstrated that the interstation magnitude scatter was significantly reduced when using the coda-based magnitudes (i.e., M{sub w}(coda) and m{sub b}(coda)). Once calibrated, the coda-derived source spectra provided stable, unbiased magnitude

  13. Technique for detecting a small magnitude loss of special nuclear material

    International Nuclear Information System (INIS)

    Pike, D.H.; Chernick, M.R.; Downing, D.J.

    The detection of losses of special nuclear materials has been the subject of much research in recent years. The standard industry practice using ID/LEID will detect large magnitude losses. Time series techniques such as the Kalman Filter or CUSUM methods will detect small magnitude losses if they occur regularly over a sustained period of time. To date no technique has been proposed which adequately addresses the problem of detecting a small magnitude loss occurring in a single period. This paper proposes a method for detecting a small magnitude loss. The approach makes use of the influence function of Hempel. The influence function measures the effect of a single inventory difference on a group of statistics. An inventory difference for a period in which a loss occurs can be expected to produce an abnormality in the calculated statistics. This abnormality is measurable by the influence function. It is shown that a one period loss smaller in magnitude than the LEID can be detected using this approach

  14. Earthquake magnitudes based on Coda-Derived Moment-Rate Spectra in Taiwan

    Science.gov (United States)

    Tu, F.; Gung, Y.; Yoo, S.; Rhie, J.

    2010-12-01

    We use the coda-derived moment-rate spectra method to estimate earthquake magnitudes in Taiwan. We extract coda-envelope at several frequency bands ranging from 0.03 to 8.0 hz using the horizontal component of broad-band waveform data recorded by BATS (Broadband Array in Taiwan for Siemology). We derived synthetic coda-envelope using various empirical frequency-dependent corrections mainly based upon Mayeda et al. (2003), which may account for all propagation, site and S-to-coda transfer function effects. After proper calibration and distance-corrections, the dimensionless coda amplitudes are used to determine the earthquake magnitude and source spectra. Selected events with magnitudes between 4 and 6 that occurred in 2009 are used to derive the empirical corrections and calibrations. We present detailed results of each procedure. Moreover, with the empirical corrections, we apply this measurement to an expanded data set and compare the derived coda-magnitude with other magnitude scales derived from conventional methods.

  15. A General Method to Estimate Earthquake Moment and Magnitude using Regional Phase Amplitudes

    Energy Technology Data Exchange (ETDEWEB)

    Pasyanos, M E

    2009-11-19

    This paper presents a general method of estimating earthquake magnitude using regional phase amplitudes, called regional M{sub o} or regional M{sub w}. Conceptually, this method uses an earthquake source model along with an attenuation model and geometrical spreading which accounts for the propagation to utilize regional phase amplitudes of any phase and frequency. Amplitudes are corrected to yield a source term from which one can estimate the seismic moment. Moment magnitudes can then be reliably determined with sets of observed phase amplitudes rather than predetermined ones, and afterwards averaged to robustly determine this parameter. We first examine in detail several events to demonstrate the methodology. We then look at various ensembles of phases and frequencies, and compare results to existing regional methods. We find regional M{sub o} to be a stable estimator of earthquake size that has several advantages over other methods. Because of its versatility, it is applicable to many more events, particularly smaller events. We make moment estimates for earthquakes ranging from magnitude 2 to as large as 7. Even with diverse input amplitude sources, we find magnitude estimates to be more robust than typical magnitudes and existing regional methods and might be tuned further to improve upon them. The method yields a more meaningful quantity of seismic moment, which can be recast as M{sub w}. Lastly, it is applied here to the Middle East region using an existing calibration model, but it would be easy to transport to any region with suitable attenuation calibration.

  16. Numerical experiments to investigate the accuracy of broad-band moment magnitude, Mwp

    Science.gov (United States)

    Hara, Tatsuhiko; Nishimura, Naoki

    2011-12-01

    We perform numerical experiments to investigate the accuracy of broad-band moment magnitude, Mwp. We conduct these experiments by measuring Mwp from synthetic seismograms and comparing the resulting values to the moment magnitudes used in the calculation of synthetic seismograms. In the numerical experiments using point sources, we have found that there is a significant dependence of Mwp on focal mechanisms, and that depths phases have a large impact on Mwp estimates, especially for large shallow earthquakes. Numerical experiments using line sources suggest that the effects of source finiteness and rupture propagation on Mwp estimates are on the order of 0.2 magnitude units for vertical fault planes with pure dip-slip mechanisms and 45° dipping fault planes with pure dip-slip (thrust) mechanisms, but that the dependence is small for strike-slip events on a vertical fault plane. Numerical experiments for huge thrust faulting earthquakes on a fault plane with a shallow dip angle suggest that the Mwp estimates do not saturate in the moment magnitude range between 8 and 9, although they are underestimates. Our results are consistent with previous studies that compared Mwp estimates to moment magnitudes calculated from seismic moment tensors obtained by analyses of observed data.

  17. Relationships between moment magnitude and fault parameters: theoretical and semi-empirical relationships

    Science.gov (United States)

    Wang, Haiyun; Tao, Xiaxin

    2003-12-01

    Fault parameters are important in earthquake hazard analysis. In this paper, theoretical relationships between moment magnitude and fault parameters including subsurface rupture length, downdip rupture width, rupture area, and average slip over the fault surface are deduced based on seismological theory. These theoretical relationships are further simplified by applying similarity conditions and an unique form is established. Then, combining the simplified theoretical relationships between moment magnitude and fault parameters with seismic source data selected in this study, a practical semi-empirical relationship is established. The seismic source data selected is also to used to derive empirical relationships between moment magnitude and fault parameters by the ordinary least square regression method. Comparisons between semi-empirical relationships and empirical relationships show that the former depict distribution trends of data better than the latter. It is also observed that downdip rupture widths of strike slip faults are saturated when moment magnitude is more than 7.0, but downdip rupture widths of dip slip faults are not saturated in the moment magnitude ranges of this study.

  18. Per unit representation of electrical magnitudes in batteries: A tool for comparison and design

    International Nuclear Information System (INIS)

    Gauchia, Lucia; Sanz, Javier

    2009-01-01

    When a comparison between the performance of batteries with different characteristics, or sizing of a particular battery system in a power system (electrical grid, etc.) is carried out, the usual expression of electrical variables in terms of absolute magnitudes (Volts, etc.) has some important disadvantages derived from the wide range of values these variables can assume, as they are dependant on the 'size' of the system, defined by its rated capacity, voltage or current. This makes impossible any direct comparison between different alternatives. Furthermore, it collides with the usual way power engineers use to represent and analyze the electrical power system. This paper proposes the application of a per unit system to batteries to overcome these problems. In this per unit system, all magnitudes are represented as non-dimensional values, with reference to a set of base magnitudes. Therefore, absolute values are converted into relative ones, which allow a direct comparison between different batteries. To apply a per unit system, a set of base magnitudes is studied and defined taking into account the special characteristics of a battery. The conclusion is that with a per unit system the information extracted is more accessible, direct and representative than using absolute magnitudes

  19. Symbolic Numerical Magnitude Processing Is as Important to Arithmetic as Phonological Awareness Is to Reading.

    Directory of Open Access Journals (Sweden)

    Kiran Vanbinst

    Full Text Available In this article, we tested, using a 1-year longitudinal design, whether symbolic numerical magnitude processing or children's numerical representation of Arabic digits, is as important to arithmetic as phonological awareness is to reading. Children completed measures of symbolic comparison, phonological awareness, arithmetic, reading at the start of third grade and the latter two were retested at the start of fourth grade. Cross-sectional and longitudinal correlations indicated that symbolic comparison was a powerful domain-specific predictor of arithmetic and that phonological awareness was a unique predictor of reading. Crucially, the strength of these independent associations was not significantly different. This indicates that symbolic numerical magnitude processing is as important to arithmetic development as phonological awareness is to reading and suggests that symbolic numerical magnitude processing is a good candidate for screening children at risk for developing mathematical difficulties.

  20. Multi-objective control of nonlinear boiler-turbine dynamics with actuator magnitude and rate constraints.

    Science.gov (United States)

    Chen, Pang-Chia

    2013-01-01

    This paper investigates multi-objective controller design approaches for nonlinear boiler-turbine dynamics subject to actuator magnitude and rate constraints. System nonlinearity is handled by a suitable linear parameter varying system representation with drum pressure as the system varying parameter. Variation of the drum pressure is represented by suitable norm-bounded uncertainty and affine dependence on system matrices. Based on linear matrix inequality algorithms, the magnitude and rate constraints on the actuator and the deviations of fluid density and water level are formulated while the tracking abilities on the drum pressure and power output are optimized. Variation ranges of drum pressure and magnitude tracking commands are used as controller design parameters, determined according to the boiler-turbine's operation range. Copyright © 2012 ISA. Published by Elsevier Ltd. All rights reserved.

  1. Color-magnitude diagrams for six metal-rich, low-latitude globular clusters

    Science.gov (United States)

    Armandroff, Taft E.

    1988-01-01

    Colors and magnitudes for stars on CCD frames for six metal-rich, low-latitude, previously unstudied globular clusters and one well-studied, metal-rich cluster (47 Tuc) have been derived and color-magnitude diagrams have been constructed. The photometry for stars in 47 Tuc are in good agreement with previous studies, while the V magnitudes of the horizontal-branch stars in the six program clusters do not agree with estimates based on secondary methods. The distances to these clusters are different from prior estimates. Redding values are derived for each program cluster. The horizontal branches of the program clusters all appear to lie entirely redwards of the red edge of the instability strip, as is normal for their metallicities.

  2. Noise measurement from magnitude MRI using local estimates of variance and skewness

    International Nuclear Information System (INIS)

    Rajan, Jeny; Poot, Dirk; Juntu, Jaber; Sijbers, Jan

    2010-01-01

    In this note, we address the estimation of the noise level in magnitude magnetic resonance (MR) images in the absence of background data. Most of the methods proposed earlier exploit the Rayleigh distributed background region in MR images to estimate the noise level. These methods, however, cannot be used for images where no background information is available. In this note, we propose two different approaches for noise level estimation in the absence of the image background. The first method is based on the local estimation of the noise variance using maximum likelihood estimation and the second method is based on the local estimation of the skewness of the magnitude data distribution. Experimental results on synthetic and real MR image datasets show that the proposed estimators accurately estimate the noise level in a magnitude MR image, even without background data. (note)

  3. Transformation of Pan-STARRS1 gri to Stetson BVRI magnitudes. Photometry of small bodies observations.

    Science.gov (United States)

    Kostov, A.; Bonev, T.

    2018-02-01

    The UBVRI broad band photometric system is widely used in CCD astronomy. There are a lot of sets of standard stars for this photometric system, the Landolt's and Stetson's catalogues being the most precise and reliable. Another photometric system, recently considerably spread in CCD observations is ugriz, which originates from the Sloan Digital Sky Survey (SDSS) and has now many variations based on its 5 broad-band filters. One of the photometric systems based on it is The Panoramic Survey Telescope and Rapid Response System (Pan-STARRS). In this paper we compare the BVRI magnitudes in the Stetson catalogue of standard stars with the magnitudes of the corresponding stars in the Pan-STARRS1 (PS1) grizyw catalogue. Transformations between these two systems are presented and discussed. An algorithm for data reduction and calibration is developed and its functionality is demonstrated in the magnitude determination of an asteroid.

  4. Frequency sensitive moment tensor inversion for light to moderate magnitude earthquakes in eastern Africa

    Science.gov (United States)

    Barth, A.; Wenzel, F.; Giardini, D.

    2007-08-01

    We provide a procedure for the routine determination of moment tensors from earthquakes with magnitudes as low as M W 4.4 using data recorded by only a few permanent seismic stations at regional to teleseismic distances. Waveforms are inverted for automatically determined frequency pass-bands that depend on source-receiver locations as well as the earthquake magnitude. Inversion results are stable against small variations in the frequency band and provide low data variances, i.e., a good fit between observed and modelled waveform traces. The total frequency band used for our procedure ranges from 10 mHz to 29 mHz (periods of 35 s to 100 s). This enables us to determine focal mechanisms for earthquakes that were not derived previously by routine procedures of CMT or other agencies. As a case study, we determine focal mechanism solutions of 38 light to moderate magnitude earthquakes in eastern Africa between 1995 and 2002.

  5. Seismicity Controlled by a Frictional Afterslip During a Small-Magnitude Seismic Sequence (ML Taiwan

    Science.gov (United States)

    Canitano, Alexandre; Godano, Maxime; Hsu, Ya-Ju; Lee, Hsin-Ming; Linde, Alan T.; Sacks, Selwyn

    2018-02-01

    We report evidence for frictional afterslip at shallow depths (about 5 to 7 km) during a small-magnitude seismic sequence (with MLTaiwan. The afterslip, which was recorded by a nearby borehole dilatometer, lasted about a month with a cumulative geodetic moment magnitude of 4.8 ± 0.2. The afterslip comprised two stages and controlled the aftershock sequence. The first postseismic stage, which followed a ML 4.6 earthquake, lasted about 6 h and mostly controlled the ruptures of neighboring asperities (e.g., multiplets) near the hypocenter. Then, a 4 week duration large afterslip event following a ML 4.9 earthquake controlled the rate of aftershocks during its first 2 days through brittle creep. The study presents a rare case of simultaneous seismological and geodetic observations for afterslip following earthquakes with magnitude lower than 5. Furthermore, the geodetic moment of the postseismic phase is at least equivalent to the coseismic moment of the sequence.

  6. Deformation mechanisms of bent Si nanowires governed by the sign and magnitude of strain

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lihua, E-mail: wlh@bjut.edu.cn, E-mail: xdhan@bjut.edu.cn, E-mail: j.zou@uq.edu.au [Beijing Key Lab of Microstructure and Property of Advanced Material, Institute of Microstructure and Properties of Advanced Materials, Beijing University of Technology, Beijing 100124 (China); Materials Engineering, The University of Queensland, Brisbane, QLD 4072 (Australia); Kong, Deli; Xin, Tianjiao; Shu, Xinyu; Zheng, Kun; Xiao, Lirong; Sha, Xuechao; Lu, Yan; Han, Xiaodong, E-mail: wlh@bjut.edu.cn, E-mail: xdhan@bjut.edu.cn, E-mail: j.zou@uq.edu.au [Beijing Key Lab of Microstructure and Property of Advanced Material, Institute of Microstructure and Properties of Advanced Materials, Beijing University of Technology, Beijing 100124 (China); Zhang, Ze [Department of Materials Science, Zhejiang University, Hangzhou 310008 (China); Zou, Jin, E-mail: wlh@bjut.edu.cn, E-mail: xdhan@bjut.edu.cn, E-mail: j.zou@uq.edu.au [Materials Engineering, The University of Queensland, Brisbane, QLD 4072 (Australia); Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, QLD 4072 (Australia)

    2016-04-11

    In this study, the deformation mechanisms of bent Si nanowires are investigated at the atomic scale with bending strain up to 12.8%. The sign and magnitude of the applied strain are found to govern their deformation mechanisms, in which the dislocation types (full or partial dislocations) can be affected by the sign (tensile or compressive) and magnitude of the applied strain. In the early stages of bending, plastic deformation is controlled by 60° full dislocations. As the bending increases, Lomer dislocations can be frequently observed. When the strain increases to a significant level, 90° partial dislocations induced from the tensile surfaces of the bent nanowires are observed. This study provides a deeper understanding of the effect of the sign and magnitude of the bending strain on the deformation mechanisms in bent Si nanowires.

  7. How Deep Is Your SNARC? Interactions Between Numerical Magnitude, Response Hands, and Reachability in Peripersonal Space

    Directory of Open Access Journals (Sweden)

    Johannes Lohmann

    2018-05-01

    Full Text Available Spatial, physical, and semantic magnitude dimensions can influence action decisions in human cognitive processing and interact with each other. For example, in the spatial-numerical associations of response code (SNARC effect, semantic numerical magnitude facilitates left-hand or right-hand responding dependent on the small or large magnitude of number symbols. SNARC-like interactions of numerical magnitudes with the radial spatial dimension (depth were postulated from early on. Usually, the SNARC effect in any direction is investigated using fronto-parallel computer monitors for presentation of stimuli. In such 2D setups, however, the metaphorical and literal interpretation of the radial depth axis with seemingly close/far stimuli or responses are not distinct. Hence, it is difficult to draw clear conclusions with respect to the contribution of different spatial mappings to the SNARC effect. In order to disentangle the different mappings in a natural way, we studied parametrical interactions between semantic numerical magnitude, horizontal directional responses, and perceptual distance by means of stereoscopic depth in an immersive virtual reality (VR. Two VR experiments show horizontal SNARC effects across all spatial displacements in traditional latency measures and kinematic response parameters. No indications of a SNARC effect along the depth axis, as it would be predicted by a direct mapping account, were observed, but the results show a non-linear relationship between horizontal SNARC slopes and physical distance. Steepest SNARC slopes were observed for digits presented close to the hands. We conclude that spatial-numerical processing is susceptible to effector-based processes but relatively resilient to task-irrelevant variations of radial-spatial magnitudes.

  8. How Deep Is Your SNARC? Interactions Between Numerical Magnitude, Response Hands, and Reachability in Peripersonal Space.

    Science.gov (United States)

    Lohmann, Johannes; Schroeder, Philipp A; Nuerk, Hans-Christoph; Plewnia, Christian; Butz, Martin V

    2018-01-01

    Spatial, physical, and semantic magnitude dimensions can influence action decisions in human cognitive processing and interact with each other. For example, in the spatial-numerical associations of response code (SNARC) effect, semantic numerical magnitude facilitates left-hand or right-hand responding dependent on the small or large magnitude of number symbols. SNARC-like interactions of numerical magnitudes with the radial spatial dimension (depth) were postulated from early on. Usually, the SNARC effect in any direction is investigated using fronto-parallel computer monitors for presentation of stimuli. In such 2D setups, however, the metaphorical and literal interpretation of the radial depth axis with seemingly close/far stimuli or responses are not distinct. Hence, it is difficult to draw clear conclusions with respect to the contribution of different spatial mappings to the SNARC effect. In order to disentangle the different mappings in a natural way, we studied parametrical interactions between semantic numerical magnitude, horizontal directional responses, and perceptual distance by means of stereoscopic depth in an immersive virtual reality (VR). Two VR experiments show horizontal SNARC effects across all spatial displacements in traditional latency measures and kinematic response parameters. No indications of a SNARC effect along the depth axis, as it would be predicted by a direct mapping account, were observed, but the results show a non-linear relationship between horizontal SNARC slopes and physical distance. Steepest SNARC slopes were observed for digits presented close to the hands. We conclude that spatial-numerical processing is susceptible to effector-based processes but relatively resilient to task-irrelevant variations of radial-spatial magnitudes.

  9. PROBLEMAS DE ESTIMACIÓN DE MAGNITUDES NO ALCANZABLES: ESTRATEGIAS Y ÉXITO EN LA RESOLUCIÓN (Unreachable Magnitude Estimation Problems: Strategies and Solving Success

    Directory of Open Access Journals (Sweden)

    Núria Gorgorió

    2013-03-01

    Full Text Available Llamamos problemas de Fermi a aquellos problemas que, siendo de difícil resolución, admiten una aproximación a su solución a base de romper el problema en partes más pequeñas y resolverlas por separado. En este artículo presentamos los problemas de estimación de magnitudes no alcanzables (PEMNA como un subconjunto de los problemas de Fermi. A partir de los datos recopilados en un estudio hecho con alumnos de 12 a 16 años, caracterizamos las distintas estrategias de resolución propuestas por estos y discutimos sobre la potencialidad de estas estrategias para resolver los problemas con éxito. Fermi problems are problems that, being difficult to solve, can be satisfactorily solved if they are broken down into smaller pieces that are solved separately. In this article, we present inconceivable magnitude estimation problems as a subset of Fermi problems. Based on data collected from a study carried out with 12 to 16 years old students, we describe the different strategies for solving the problems that were proposed by the students, and discuss the potential of these strategies to successfully solve the problems.

  10. Kant and the magnitude of sensation: a neglected prologue to modern psychophysics.

    Science.gov (United States)

    Baumann, Christian

    2008-01-01

    Quantitative relations between the sensations and the stimuli that produce them are the domain of psychophysics, a branch of natural science not yet known at the time of Immanuel Kant (1724-1804). But Kant's philosophical doctrines of perception imply that sensations can be quantified. Accordingly, he proposed not only to consider the magnitude of both sensations and stimuli but also to work out an appropriate mathematics that would relate these magnitudes to each other. This part of Kant's work received almost no attention up to the present time although it contains some essential elements of modern psychophysics.

  11. Life on the Number Line: Routes to Understanding Fraction Magnitude for Students With Difficulties Learning Mathematics.

    Science.gov (United States)

    Gersten, Russell; Schumacher, Robin F; Jordan, Nancy C

    Magnitude understanding is critical for students to develop a deep understanding of fractions and more advanced mathematics curriculum. The research reports in this special issue underscore magnitude understanding for fractions and emphasize number lines as both an assessment and an instructional tool. In this commentary, we discuss how number lines broaden the concept of fractions for students who are tied to the more general part-whole representations of area models. We also discuss how number lines, compared to other representations, are a superior and more mathematically correct way to explain fraction concepts.

  12. Moment Magnitude Determination for Marmara Region-Turkey Using Displacement Spectra

    Science.gov (United States)

    Köseoǧlu Küsmezer, Ayşegül; Meral Özel, Nurcan; Barış, Å.žErif; Üçer, S. Balamir; Ottemöller, Lars

    2010-05-01

    The main purpose of the study is to determine moment magnitude Mω using displacement source spectra of earthquakes occurred in Marmara Region. The region is the most densely populated and fast-developing part of Turkey, bounded by 39.0°N to 42.0°N and 26.0°E to 32.0°E, and have experienced major earthquake disasters during the last four centuries with destructive earthquakes and probabilistic seismic hazard studies shows that the region have significant probability of producing M>7 earthquake within the next years. Seismic moment is a direct measurement of earthquake size (rupture area and static displacement) and does not saturate, spectral analysis at local distances is a very useful method which allows the reliable determination of seismic moment and moment magnitude. We have used converging grid search method developed by L. Ottemöller, and J. Havskov, 2008 for the automatic determination of moment magnitude for local distances. For data preperation; the time domain signal of S waves were extracted from the vertical component seismograms.Data was transformed from time to frequency domain by applying the standart fast fourier transform (fft). Source parameters and moment magnitudes of earthquakes are determined by applying spectral fitting procedure to classical Brune's model. The method is first manually and then automatically performed on the source spectrum of S waves within 20 sec. Mo and fc (Aki;1967, and Brune;1970) were determined by using the method which the model space is divided into a grid and the error function detected for all grid points. A smaller grid with denser spacing around the best solution is generated with an iterative procedure. The moment magnitudes of the earthquakes have been calculated according to the scale of Kanamori (1977) and Hanks and Kanamori (1979). A data set of 279 events recorded on broadband velocity seismograms extracted from KOERI (Kandilli Observatory and Earthquake Research Institute) seismic network were

  13. Influence of biases in numerical magnitude allocation on human prosocial decision making.

    Science.gov (United States)

    Arshad, Qadeer; Nigmatullina, Yuliya; Siddiqui, Shuaib; Franka, Mustafa; Mediratta, Saniya; Ramachandaran, Sanjeev; Lobo, Rhannon; Malhotra, Paresh A; Roberts, R E; Bronstein, Adolfo M

    2017-12-01

    Over the past decade neuroscientific research has attempted to probe the neurobiological underpinnings of human prosocial decision making. Such research has almost ubiquitously employed tasks such as the dictator game or similar variations (i.e., ultimatum game). Considering the explicit numerical nature of such tasks, it is surprising that the influence of numerical cognition on decision making during task performance remains unknown. While performing these tasks, participants typically tend to anchor on a 50:50 split that necessitates an explicit numerical judgement (i.e., number-pair bisection). Accordingly, we hypothesize that the decision-making process during the dictator game recruits overlapping cognitive processes to those known to be engaged during number-pair bisection. We observed that biases in numerical magnitude allocation correlated with the formulation of decisions during the dictator game. That is, intrinsic biases toward smaller numerical magnitudes were associated with the formulation of less favorable decisions, whereas biases toward larger magnitudes were associated with more favorable choices. We proceeded to corroborate this relationship by subliminally and systematically inducing biases in numerical magnitude toward either higher or lower numbers using a visuo-vestibular stimulation paradigm. Such subliminal alterations in numerical magnitude allocation led to proportional and corresponding changes to an individual's decision making during the dictator game. Critically, no relationship was observed between neither intrinsic nor induced biases in numerical magnitude on decision making when assessed using a nonnumerical-based prosocial questionnaire. Our findings demonstrate numerical influences on decisions formulated during the dictator game and highlight the necessity to control for confounds associated with numerical cognition in human decision-making paradigms. NEW & NOTEWORTHY We demonstrate that intrinsic biases in numerical magnitude

  14. Perspectives on the Salience and Magnitude of Dam Impacts for Hydro Development Scenarios in China

    Directory of Open Access Journals (Sweden)

    Desiree Tullos

    2010-06-01

    Survey results indicate differences in the perceived salience and magnitude of impacts across both expert groups and dam scenarios. Furthermore, surveys indicate that stakeholder perceptions changed as the information provided regarding dam impacts became more specific, suggesting that stakeholder evaluation may be influenced by quality of information. Finally, qualitative comments from the survey reflect some of the challenges of interdisciplinary dam assessment, including cross-disciplinary cooperation, data standardisation and weighting, and the distribution and potential mitigation of impacts. Given the complexity of data and perceptions around dam impacts, decision-support tools that integrate the objective magnitude and perceived salience of impacts are required urgently.

  15. How Sequential Changes in Reward Magnitude Modulate Cognitive Flexibility: Evidence from Voluntary Task Switching

    Science.gov (United States)

    Fröber, Kerstin; Dreisbach, Gesine

    2016-01-01

    There is much evidence that the prospect of reward modulates cognitive control in terms of more stable behavior. Increases in expected reward magnitude, however, have been suggested to increase flexible behavior as evidenced by reduced switch costs. In a series of experiments, the authors provide evidence that this increased cognitive flexibility…

  16. Listening to the 2011 magnitude 9.0 Tohoku-Oki, Japan, earthquake

    Science.gov (United States)

    Peng, Zhigang; Aiken, Chastity; Kilb, Debi; Shelly, David R.; Enescu, Bogdan

    2012-01-01

    The magnitude 9.0 Tohoku-Oki, Japan, earthquake on 11 March 2011 is the largest earthquake to date in Japan’s modern history and is ranked as the fourth largest earthquake in the world since 1900. This earthquake occurred within the northeast Japan subduction zone (Figure 1), where the Pacific plate is subducting beneath the Okhotsk plate at rate of ∼8–9 cm/yr (DeMets et al. 2010). This type of extremely large earthquake within a subduction zone is generally termed a “megathrust” earthquake. Strong shaking from this magnitude 9 earthquake engulfed the entire Japanese Islands, reaching a maximum acceleration ∼3 times that of gravity (3 g). Two days prior to the main event, a foreshock sequence occurred, including one earthquake of magnitude 7.2. Following the main event, numerous aftershocks occurred around the main slip region; the largest of these was magnitude 7.9. The entire foreshocks-mainshock-aftershocks sequence was well recorded by thousands of sensitive seismometers and geodetic instruments across Japan, resulting in the best-recorded megathrust earthquake in history. This devastating earthquake resulted in significant damage and high death tolls caused primarily by the associated large tsunami. This tsunami reached heights of more than 30 m, and inundation propagated inland more than 5 km from the Pacific coast, which also caused a nuclear crisis that is still affecting people’s lives in certain regions of Japan.

  17. Monetary reward magnitude effects on behavior and brain function during goal-directed behavior.

    Science.gov (United States)

    Rosell-Negre, P; Bustamante, J C; Fuentes-Claramonte, P; Costumero, V; Benabarre, S; Barrós-Loscertales, A

    2017-08-01

    Reward may modulate the cognitive processes required for goal achievement, while individual differences in personality may affect reward modulation. Our aim was to test how different monetary reward magnitudes modulate brain activation and performance during goal-directed behavior, and whether individual differences in reward sensitivity affect this modulation. For this purpose, we scanned 37 subjects with a parametric design in which we varied the magnitude of monetary rewards (€0, €0.01, €0.5, €1 or €1.5) in a blocked fashion while participants performed an interference counting-Stroop condition. The results showed that the brain activity of left dorsolateral prefrontal cortex (DLPFC) and the striatum were modulated by increasing and decreasing reward magnitudes, respectively. Behavioral performance improved as the magnitude of monetary reward increased while comparing the non reward (€0) condition to any other reward condition, or the lower €0.01 to any other reward condition, and this improvement was related with individual differences in reward sensitivity. In conclusion, the locus of influence of monetary incentives overlaps the activity of the regions commonly involved in cognitive control.

  18. The Relationship between Spatial and Temporal Magnitude Estimation of Scientific Concepts at Extreme Scales

    Science.gov (United States)

    Price, Aaron; Lee, H.

    2010-01-01

    Many astronomical objects, processes, and events exist and occur at extreme scales of spatial and temporal magnitudes. Our research draws upon the psychological literature, replete with evidence of linguistic and metaphorical links between the spatial and temporal domains, to compare how students estimate spatial and temporal magnitudes associated with objects and processes typically taught in science class.. We administered spatial and temporal scale estimation tests, with many astronomical items, to 417 students enrolled in 12 undergraduate science courses. Results show that while the temporal test was more difficult, students’ overall performance patterns between the two tests were mostly similar. However, asymmetrical correlations between the two tests indicate that students think of the extreme ranges of spatial and temporal scales in different ways, which is likely influenced by their classroom experience. When making incorrect estimations, students tended to underestimate the difference between the everyday scale and the extreme scales on both tests. This suggests the use of a common logarithmic mental number line for both spatial and temporal magnitude estimation. However, there are differences between the two tests in the errors student make in the everyday range. Among the implications discussed is the use of spatio-temporal reference frames, instead of smooth bootstrapping, to help students maneuver between scales of magnitude and the use of logarithmic transformations between reference frames. Implications for astronomy range from learning about spectra to large scale galaxy structure.

  19. The main sequence of NGC 6231 and the calibration of absolute magnitudes

    International Nuclear Information System (INIS)

    Garrison, R.F.

    1978-01-01

    The author presents a discussion of a new approach to the calibration of absolute magnitudes for MK spectral types. With the addition of the NGC 6231 main sequence down to A0, the material for the cluster fitting method using very carefully determined MK types is complete. (Auth.)

  20. Earthquakes clustering based on the magnitude and the depths in Molluca Province

    Energy Technology Data Exchange (ETDEWEB)

    Wattimanela, H. J., E-mail: hwattimaela@yahoo.com [Pattimura University, Ambon (Indonesia); Institute of Technology Bandung, Bandung (Indonesia); Pasaribu, U. S.; Indratno, S. W.; Puspito, A. N. T. [Institute of Technology Bandung, Bandung (Indonesia)

    2015-12-22

    In this paper, we present a model to classify the earthquakes occurred in Molluca Province. We use K-Means clustering method to classify the earthquake based on the magnitude and the depth of the earthquake. The result can be used for disaster mitigation and for designing evacuation route in Molluca Province.

  1. Earthquakes clustering based on the magnitude and the depths in Molluca Province

    International Nuclear Information System (INIS)

    Wattimanela, H. J.; Pasaribu, U. S.; Indratno, S. W.; Puspito, A. N. T.

    2015-01-01

    In this paper, we present a model to classify the earthquakes occurred in Molluca Province. We use K-Means clustering method to classify the earthquake based on the magnitude and the depth of the earthquake. The result can be used for disaster mitigation and for designing evacuation route in Molluca Province

  2. Transmission of low-magnitude seismic excitation into Hanford Site structures

    International Nuclear Information System (INIS)

    Weiner, E.O.

    1989-01-01

    Several Hanford Site buildings were analyzed using simplified models to gain insight as to what extent the free field motion of a small-magnitude earthquake is transmitted into building structures as a result of soil-structure interaction effects. Building selection included the Plutonium Processing Plant, B-Plant and the Fast Flux Test Facility containment which represented a variety of stiffnesses, weights, and embedments. An artificial time history for the free field has a peak response at 13 Hz. This motion represents a median for magnitude 4 and 4.5 earthquakes, respectively. Floor response spectra were compared with results from analyses to design basis ground motions using the same structural models. Considerable attenuation of the small-magnitude free-field motion was found in the case of stiff, deeply embedded structures. This attenuation is attributed to kinematic interaction in addition to attenuation with depth in the free field. Even with such attenuation, there are exceptions where small magnitude responses exceed design basis responses. They are generally associated with 10 to 20 Hz modes with vertical motion

  3. Reliability and Magnitude of Laterality Effects in Dichotic Listening with Exogenous Cueing

    Science.gov (United States)

    Voyer, Daniel

    2004-01-01

    The purpose of the present study was to replicate and extend to word recognition previous findings of reduced magnitude and reliability of laterality effects when exogenous cueing was used in a dichotic listening task with syllable pairs. Twenty right-handed undergraduate students with normal hearing (10 females, 10 males) completed a dichotic…

  4. Detrital carbon pools in temperate forests: magnitude and potential for landscape-scale assessment

    Science.gov (United States)

    John Bradford; Peter Weishampel; Marie-Louise Smith; Randall Kolka; Richard A. Birdsey; Scott V. Ollinger; Michael G. Ryan

    2009-01-01

    Reliably estimating carbon storage and cycling in detrital biomass is an obstacle to carbon accounting. We examined carbon pools and fluxes in three small temperate forest landscapes to assess the magnitude of carbon stored in detrital biomass and determine whether detrital carbon storage is related to stand structural properties (leaf area, aboveground biomass,...

  5. The Concept of Magnitude and What It Tells Us about How Struggling Students Learn Fractions

    Science.gov (United States)

    Woodward, John

    2017-01-01

    This commentary summarizes emerging research into fractions instruction for students who are at risk for failure. Each of the three articles emphasizes a measure conception of fractions. Teaching fractions as measurement helps students learn the magnitude of rational numbers. However, measurement is only part of the way that students should…

  6. Typical whole body vibration exposure magnitudes encountered in the open pit mining industry.

    Science.gov (United States)

    Howard, Bryan; Sesek, Richard; Bloswick, Don

    2009-01-01

    According to recent research, a causal link has been established between occupational exposure to whole body vibration and an increased occurrence of low back pain. To aid in the further development of an in-house health and safety program for a large open pit mining facility interested in reducing back pain among its operators, whole body vibration magnitudes were characterized for a range of jobs. Specifically, thirty-five individual jobs from five different areas across the facility were evaluated for tri-axial acceleration levels during normal operating conditions. Tri-axial acceleration magnitudes were categorized into thirteen job groups. Job groups were ranked according to exposure and compared to the ISO 2631-1 standard for health risk assessment. Three of the thirteen job groups produced tri-axial acceleration magnitudes below the ISO 2631-1 low/moderate health caution limit for a twelve hour exposure. Six of the thirteen job groups produced exposures within the moderate health risk range. Four job groups were found to subject operators to WBV acceleration magnitudes above the moderate/high health caution limit.

  7. Magnitude scaling relationship from the first P-wave arrivals on Canada's west coast

    Science.gov (United States)

    Eshaghi, A.; Tiampo, K. F.

    2011-12-01

    The empirical magnitude scaling relationship from ground-motion period parameter τc is derived using vertical waveforms recorded in the Cascadia Subduction Zone (CSZ) along Canada's west coast. A high-pass filtered displacement amplitude parameter, Pd, is calculated from the initial 3 s of the P waveforms and the empirical relationship between Pd and peak ground velocity, PGV, is derived using the same data set. We selected earthquakes of M >3.0 recorded during 1996-2009 by the seismic network stations in the region operated by National Resources Canada (NRCan). In total, 90 events were selected and the vertical components of the earthquakes signals were converted to ground velocity and displacement. The displacements were filtered with a one-way Butterworth high-pass filter with a cut-off frequency of 0.075 Hz. Pd and τc are computed from the vertical seismogram components. While the average magnitude error was approximately 0.70 magnitude units when using the individual record, the error dropped to approximately 0.5 magnitude units when using the average τc for each event. In case of PGV, the average error is approximately 0.3. These relationships may be used for initial steps in establishing an earthquake early warning system for the CSZ.

  8. Research on temperature characteristics of laser energy meter absorber irradiated by ms magnitude long pulse laser

    Science.gov (United States)

    Li, Nan; Qiao, Chunhong; Fan, Chengyu; Zhang, Jinghui; Yang, Gaochao

    2017-10-01

    The research on temperature characteristics for large-energy laser energy meter absorber is about continuous wave (CW) laser before. For the measuring requirements of millisecond magnitude long pulse laser energy, the temperature characteristics for absorber are numerically calculated and analyzed. In calculation, the temperature field distributions are described by heat conduction equations, and the metal cylinder cavity is used for absorber model. The results show that, the temperature of absorber inwall appears periodic oscillation with pulse structure, the oscillation period and amplitude respectively relate to the pulse repetition frequency and single pulse energy. With the wall deep increasing, the oscillation amplitude decreases rapidly. The temperature of absorber outerwall is without periodism, and rises gradually with time. The factors to affect the temperature rise of absorber are single pulse energy, pulse width and repetition frequency. When the laser irradiation stops, the temperature between absorber inwall and outerwall will reach agreement rapidly. After special technology processing to enhance the capacity of resisting laser damage for absorber inwall, the ms magnitude long pulse laser energy can be obtained with the method of measuring the temperature of absorber outerwall. Meanwhile, by optimization design of absorber structure, when the repetition frequency of ms magnitude pulse laser is less than 10Hz, the energy of every pulse for low repetition frequency pulse sequence can be measured. The work offers valuable references for the design of ms magnitude large-energy pulse laser energy meter.

  9. Magnitude and meaningfulness of change in SF-36 scores in four types of orthopedic surgery

    DEFF Research Database (Denmark)

    Busija, Lucy; Osborne, Richard H; Nilsdotter, Anna

    2008-01-01

    BACKGROUND: The Medical Outcomes General Health Survey (SF-36) is a widely used health status measure; however, limited evidence is available for its performance in orthopedic settings. The aim of this study was to examine the magnitude and meaningfulness of change and sensitivity of SF-36...

  10. Earthquake magnitude estimation using the τ c and P d method for earthquake early warning systems

    Science.gov (United States)

    Jin, Xing; Zhang, Hongcai; Li, Jun; Wei, Yongxiang; Ma, Qiang

    2013-10-01

    Earthquake early warning (EEW) systems are one of the most effective ways to reduce earthquake disaster. Earthquake magnitude estimation is one of the most important and also the most difficult parts of the entire EEW system. In this paper, based on 142 earthquake events and 253 seismic records that were recorded by the KiK-net in Japan, and aftershocks of the large Wenchuan earthquake in Sichuan, we obtained earthquake magnitude estimation relationships using the τ c and P d methods. The standard variances of magnitude calculation of these two formulas are ±0.65 and ±0.56, respectively. The P d value can also be used to estimate the peak ground motion of velocity, then warning information can be released to the public rapidly, according to the estimation results. In order to insure the stability and reliability of magnitude estimation results, we propose a compatibility test according to the natures of these two parameters. The reliability of the early warning information is significantly improved though this test.

  11. Characteristics of Gyeongju earthquake, moment magnitude 5.5 and relative relocations of aftershocks

    Science.gov (United States)

    Cho, ChangSoo; Son, Minkyung

    2017-04-01

    There is low seismicity in the korea peninsula. According historical record in the historic book, There were several strong earthquake in the korea peninsula. Especially in Gyeongju of capital city of the Silla dynasty, few strong earthquakes caused the fatalities of several hundreds people 1,300 years ago and damaged the houses and make the wall of castles collapsed. Moderate strong earthquake of moment magnitude 5.5 hit the city in September 12, 2016. Over 1000 aftershocks were detected. The numbers of occurrences of aftershock over time follows omori's law well. The distribution of relative locations of 561 events using clustering aftershocks by cross-correlation between P and S waveform of the events showed the strike NNE 25 30 o and dip 68 74o of fault plane to cause the earthquake matched with the fault plane solution of moment tensor inversion well. The depth of range of the events is from 11km to 16km. The width of distribution of event locations is about 5km length. The direction of maximum horizontal stress by inversion of stress for the moment solutions of main event and large aftershocks is similar to the known maximum horizontal stress direction of the korea peninsula. The relation curves between moment magnitude and local magnitude of aftershocks shows that the moment magnitude increases slightly more for events of size less than 2.0

  12. Moment Magnitudes of Small to Moderate Size Regional Events from Coda in the Middle East

    Science.gov (United States)

    Gok, R.; Pasyanos, M. E.; Matzel, E.; Mayeda, K. M.; Walter, W. R.

    2010-12-01

    The uneven distribution of stations and heterogeneous structure of the Middle East makes it difficult to calculate reliable moment magnitudes in the region. Such magnitudes are important for event characterization, and for yield estimation applications. The complex structure of the lithosphere in the region causes significant variation in the recorded amplitude of body and surface waves that travel along different paths. These 2-D effects are most significant for small and moderate magnitude events, which are most observable at periods 4.5) at low frequencies ( < 0.5 Hz). But even using coda waves, high frequency spectra show considerable scatter. Next, we applied tomographic inversion to the geometrical spreading corrected coda amplitudes to calculate 2-D coda Q. Coda Q results agree well with direct Lg and tectonics of the region. We observe low Q in Anatolian and Iranian plateaus and high Q in Arabian Plate. Applying the 2-D correction reduced the inter-station scatter of the higher frequency spectra, allowing us to obtain reliable moment magnitude estimates for smaller events (Mw < 4.5).

  13. Detection capability of seismic network based on noise analysis and magnitude of completeness

    Czech Academy of Sciences Publication Activity Database

    Fischer, Tomáš; Bachura, M.

    2014-01-01

    Roč. 18, č. 1 (2014), s. 137-150 ISSN 1383-4649 R&D Projects: GA MŠk LM2010008 Institutional support: RVO:67985530 Keywords : seismic monitoring * magnitude of completeness * detection capability Subject RIV: DC - Siesmology, Volcanology, Earth Structure OBOR OECD: Volcanology Impact factor: 1.386, year: 2014

  14. Preliminary Magnitude of Completeness Quantification of Improved BMKG Catalog (2008-2016) in Indonesian Region

    Science.gov (United States)

    Diantari, H. C.; Suryanto, W.; Anggraini, A.; Irnaka, T. M.; Susilanto, P.; Ngadmanto, D.

    2018-03-01

    We present a magnitude of completeness (Mc) quantification based on BMKG improved earthquake catalog which generated from Ina-TEWS seismograph network. The Mc quantification can help us determine the lowest magnitude which can be recorded perfectly as a function of space and time. We use the BMKG improved earthquake catalog from 2008 to 2016 which has been converted to moment magnitude (Mw) and declustered. The value of Mc is computed by determining the initial point of deviation patterns in Frequency Magnitude Distribution (FMD) chart following the Gutenberg-Richter equations. In the next step, we calculate the temporal variation of Mc and b-value using maximum likelihood method annually. We found that the Mc value is decreasing and produced a varying b-value. It indicates that the development of seismograph network from 2008 to 2016 can affect the value of Mc although it is not significant. We analyze temporal variation of Mc value, and correlate it with the spatial distribution of seismograph in Indonesia. The spatial distribution of seismograph installation shows that the western part of Indonesia has more dense seismograph compared to the eastern region. However, the eastern part of Indonesia has a high level of seismicity compared to the western region. Based upon the results, additional seismograph installation in the eastern part of Indonesia should be taken into consideration.

  15. The Magnitude and Time Course of Muscle Cross-section Decrease in Intensive Care Unit Patients

    NARCIS (Netherlands)

    Haaf, D. Ten; Hemmen, B.; Meent, H. van de; Bovend'Eerdt, T.J.H.

    2017-01-01

    OBJECTIVE: Bedriddenness and immobilization of patients at an intensive care unit may result in muscle atrophy and devaluation in quality of life. The exact effect of immobilization on intensive care unit patients is not known. The aim of this study was to investigate the magnitude and time course

  16. A Method for Designing FIR Filters with Arbitrary Magnitude Characteristic Used for Modeling Human Audiogram

    Directory of Open Access Journals (Sweden)

    SZOPOS, E.

    2012-05-01

    Full Text Available This paper presents an iterative method for designing FIR filters that implement arbitrary magnitude characteristics, defined by the user through a set of frequency-magnitude points (frequency samples. The proposed method is based on the non-uniform frequency sampling algorithm. For each iteration a new set of frequency samples is generated, by processing the set used in the previous run; this implies changing the samples location around the previous frequency values and adjusting their magnitude through interpolation. If necessary, additional samples can be introduced, as well. After each iteration the magnitude characteristic of the resulting filter is determined by using the non-uniform DFT and compared with the required one; if the errors are larger than the acceptable levels (set by the user a new iteration is run; the length of the resulting filter and the values of its coefficients are also taken into consideration when deciding a re-run. To demonstrate the efficiency of the proposed method a tool for designing FIR filters that match human audiograms was implemented in LabVIEW. It was shown that the resulting filters have smaller coefficients than the standard one, and can also have lower order, while the errors remain relatively small.

  17. Discounting of Delayed Food Rewards in Pigeons and Rats: Is There a Magnitude Effect

    Science.gov (United States)

    Green, Leonard; Myerson, Joel; Holt, Daniel D.; Slavin, John R.; Estle, Sara J.

    2004-01-01

    Temporal discounting refers to the decrease in the present, subjective value of a reward as the time to its receipt increases. Results from humans have shown that a hyperbola-like function describes the form of the discounting function when choices involve hypothetical monetary rewards. In addition, magnitude effects have been reported in which…

  18. Multi-dimensional self-esteem and magnitude of change in the treatment of anorexia nervosa.

    Science.gov (United States)

    Collin, Paula; Karatzias, Thanos; Power, Kevin; Howard, Ruth; Grierson, David; Yellowlees, Alex

    2016-03-30

    Self-esteem improvement is one of the main targets of inpatient eating disorder programmes. The present study sought to examine multi-dimensional self-esteem and magnitude of change in eating psychopathology among adults participating in a specialist inpatient treatment programme for anorexia nervosa. A standardised assessment battery, including multi-dimensional measures of eating psychopathology and self-esteem, was completed pre- and post-treatment for 60 participants (all white Scottish female, mean age=25.63 years). Statistical analyses indicated that self-esteem improved with eating psychopathology and weight over the course of treatment, but that improvements were domain-specific and small in size. Global self-esteem was not predictive of treatment outcome. Dimensions of self-esteem at baseline (Lovability and Moral Self-approval), however, were predictive of magnitude of change in dimensions of eating psychopathology (Shape and Weight Concern). Magnitude of change in Self-Control and Lovability dimensions were predictive of magnitude of change in eating psychopathology (Global, Dietary Restraint, and Shape Concern). The results of this study demonstrate that the relationship between self-esteem and eating disorder is far from straightforward, and suggest that future research and interventions should focus less exclusively on self-esteem as a uni-dimensional psychological construct. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. Phase retrieval from the magnitude of the Fourier transforms of nonperiodic objects

    International Nuclear Information System (INIS)

    Miao, J.; Sayre, D.; Chapman, H.N.

    1998-01-01

    It is suggested that, given the magnitude of Fourier transforms sampled at the Bragg density, the phase problem is underdetermined by a factor of 2 for 1D, 2D, and 3D objects. It is therefore unnecessary to oversample the magnitude of Fourier transforms by 2x in each dimension (i.e., oversampling by 4x for 2D and 8x for 3D) in retrieving the phase of 2D and 3D objects. Our computer phasing experiments accurately retrieved the phase from the magnitude of the Fourier transforms of 2D and 3D complex-valued objects by using positivity constraints on the imaginary part of the objects and loose supports, with the oversampling factor much less than 4 for 2D and 8 for 3D objects. Under the same conditions we also obtained reasonably good reconstructions of 2D and 3D complex-valued objects from the magnitude of their Fourier transforms with added noise and a central stop. copyright 1998 Optical Society of America

  20. (Non-)symbolic magnitude processing in children with mathematical difficulties: A meta-analysis.

    Science.gov (United States)

    Schwenk, Christin; Sasanguie, Delphine; Kuhn, Jörg-Tobias; Kempe, Sophia; Doebler, Philipp; Holling, Heinz

    2017-05-01

    Symbolic and non-symbolic magnitude representations, measured by digit or dot comparison tasks, are assumed to underlie the development of arithmetic skills. The comparison distance effect (CDE) has been suggested as a hallmark of the preciseness of mental magnitude representations. It implies that two magnitudes are harder to discriminate when the numerical distance between them is small, and may therefore differ in children with mathematical difficulties (MD), i.e. low mathematical achievement or dyscalculia. However, empirical findings on the CDE in children with MD are heterogeneous, and only few studies assess both symbolic and non-symbolic skills. This meta-analysis therefore integrates 44 symbolic and 48 non-symbolic response time (RT) outcomes reported in nineteen studies (N=1630 subjects, aged 6-14 years). Independent of age, children with MD show significantly longer mean RTs than typically achieving controls, particularly on symbolic (Hedges' g=0.75; 95% CI [0.51; 0.99]), but to a significantly lower extent also on non-symbolic (g=0.24; 95% CI [0.13; 0.36]) tasks. However, no group differences were found for the CDE. Extending recent work, these meta-analytical findings on children with MD corroborate the diagnostic importance of magnitude comparison speed in symbolic tasks. By contrast, the validity of CDE measures in assessing MD is questioned. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Beyond Valence and Magnitude: a Flexible Evaluative Coding System in the Brain

    Science.gov (United States)

    Gu, Ruolei; Lei, Zhihui; Broster, Lucas; Wu, Tingting; Jiang, Yang; Luo, Yue-jia

    2013-01-01

    Outcome evaluation is a cognitive process that plays an important role in our daily lives. In most paradigms utilized in the field of experimental psychology, outcome valence and outcome magnitude are the two major features investigated. The classical “independent coding model” suggest that outcome valence and outcome magnitude are evaluated by separate neural mechanisms that may be mapped onto discrete event-related potential (ERP) components: feedback-related negativity (FRN) and the P3, respectively. To examine this model, we presented outcome valence and magnitude sequentially rather than simultaneously. The results reveal that when only outcome valence or magnitude is known, both the FRN and the P3 encode that outcome feature; when both aspects of outcome are known, the cognitive functions of the two components dissociate: the FRN responds to the information available in the current context, while the P3 pattern depends on outcome presentation sequence. The current study indicates that the human evaluative system, indexed in part by the FRN and the P3, is more flexible than previous theories suggested. PMID:22019775

  2. Effects of different magnitudes of mechanical strain on Osteoblasts in vitro

    International Nuclear Information System (INIS)

    Tang Lin; Lin Zhu; Li Yongming

    2006-01-01

    In addition to systemic and local factors, mechanical strain plays a crucial role in bone remodeling during growth, development, and fracture healing, and especially in orthodontic tooth movement. Although many papers have been published on the effects of mechanical stress on osteoblasts or osteoblastic cells, little is known about the effects of different magnitudes of mechanical strain on such cells. In the present study, we investigated how different magnitudes of cyclic tensile strain affected osteoblasts. MC3T3-E1 osteoblastic cells were subjected to 0%, 6%, 12% or 18% elongation for 24 h using a Flexercell Strain Unit, and then the mRNA and protein expressions of osteoprotegerin (OPG) and receptor activator of nuclear factor-κB ligand (RANKL) were examined. The results showed that cyclic tensile strain induced a magnitude-dependent increase (0%, 6%, 12%, and 18%) in OPG synthesis and a concomitant decrease in RANKL mRNA expression and sRANKL release from the osteoblasts. Furthermore, the induction of OPG mRNA expression by stretching was inhibited by indomethacin or genistein, and the stretch-induced reduction of RANKL mRNA was inhibited by PD098059. These results indicate that different magnitudes of cyclic tensile strain influence the biological behavior of osteoblasts, which profoundly affects bone remodeling

  3. Determination of Love- and Rayleigh-Wave Magnitudes for Earthquakes and Explosions and Other Studies

    Science.gov (United States)

    2012-12-30

    09-C-0012 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 62601F 6. AUTHOR(S) Jessie L. Bonner, Anastasia Stroujkova, Dale Anderson, Jonathan...AND RAYLEIGH-WAVE MAGNITUDES FOR EARTHQUAKES AND EXPLOSIONS Jessie L. Bonner, Anastasia Stroujkova, and Dale Anderson INTRODUCTION Since...MAXIMUM LIKELIHOOD ESTIMATION: APPLICATION TO MIDDLE EAST EARTHQUAKE DATA Anastasia Stroujkova and Jessie Bonner Weston Geophysical Corporation

  4. The influence of resin flexural modulus on the magnitude of ceramic strengthening.

    LENUS (Irish Health Repository)

    Fleming, Garry J P

    2012-07-01

    The aim was to determine the magnitude of ceramic resin-strengthening with resin-based materials with varying flexural moduli using a regression technique to assess the theoretical strengthening at a \\'zero\\' resin-coating thickness. The hypothesis tested was that experimentally, increasing resin flexural modulus results in increased resin-strengthening observed at a theoretical \\'zero\\' resin-coating thickness.

  5. An Equivalent Moment Magnitude Earthquake Catalogue for Western Turkey and its Quantitative Properties

    Science.gov (United States)

    Leptokaropoulos, Konstantinos; Vasilios, Karakostas; Eleftheria, Papadimitriou; Aggeliki, Adamaki; Onur, Tan; Zumer, Pabuçcu

    2013-04-01

    Earthquake catalogues consist a basic product of seismology, resulting from complex procedures and suffering from natural and man-made errors. The accumulation of these problems over space and time lead to inhomogeneous catalogues which in turn lead to significant uncertainties in many kinds of analyses, such as seismicity rate evaluation and seismic hazard assessment. A major source of catalogue inhomogeneity is the variety of magnitude scales (i.e. Mw, mb, MS, ML, Md), reported from different institutions and sources. Therefore an effort is made in this study to compile a catalogue as homogenous as possible regarding the magnitude scale for the region of Western Turkey (26oE - 32oE longitude, 35oN - 43oN latitude), one of the most rapidly deforming regions worldwide with intense seismic activity, complex fault systems and frequent strong earthquakes. For this purpose we established new relationships to transform as many as possible available magnitudes into equivalent moment magnitude scale, M*w. These relations yielded by the application of the General Orthogonal Regression method and the statistical significance of the results was quantified. The final equivalent moment magnitude was evaluated by taking into consideration all the available magnitudes for which a relation was obtained and also a weight inversely proportional to their standard deviation. Once the catalogue was compiled the magnitude of completeness, Mc, was investigated in both space and time regime. The b-values and their accuracy were also calculated by the maximum likelihood estimate. The spatial and temporal constraints were selected in respect to seismicity recording level, since the state and evolution of the local and regional seismic networks are unknown. We modified and applied the Goodness of Fit test of Wiemer and Wyss (2000) in order to be more effective in datasets that are characterized by smaller sample size and higher Mcthresholds. The compiled catalogue and the Mcevaluation

  6. The relation between postural sway magnitude and metabolic energy cost during upright standing on a compliant surface.

    NARCIS (Netherlands)

    Houdijk, J.H.P.; Brown, S.; van Dieen, J.H.

    2015-01-01

    Postural control performance is often described in terms of postural sway magnitude, assuming that lower sway magnitude reflects better performance. However, people do not typically minimize sway magnitude when performing a postural control task. Possibly, other criteria are satisfied when people

  7. N-Cadherin Maintains the Healthy Biology of Nucleus Pulposus Cells under High-Magnitude Compression.

    Science.gov (United States)

    Wang, Zhenyu; Leng, Jiali; Zhao, Yuguang; Yu, Dehai; Xu, Feng; Song, Qingxu; Qu, Zhigang; Zhuang, Xinming; Liu, Yi

    2017-01-01

    Mechanical load can regulate disc nucleus pulposus (NP) biology in terms of cell viability, matrix homeostasis and cell phenotype. N-cadherin (N-CDH) is a molecular marker of NP cells. This study investigated the role of N-CDH in maintaining NP cell phenotype, NP matrix synthesis and NP cell viability under high-magnitude compression. Rat NP cells seeded on scaffolds were perfusion-cultured using a self-developed perfusion bioreactor for 5 days. NP cell biology in terms of cell apoptosis, matrix biosynthesis and cell phenotype was studied after the cells were subjected to different compressive magnitudes (low- and high-magnitudes: 2% and 20% compressive deformation, respectively). Non-loaded NP cells were used as controls. Lentivirus-mediated N-CDH overexpression was used to further investigate the role of N-CDH under high-magnitude compression. The 20% deformation compression condition significantly decreased N-CDH expression compared with the 2% deformation compression and control conditions. Meanwhile, 20% deformation compression increased the number of apoptotic NP cells, up-regulated the expression of Bax and cleaved-caspase-3 and down-regulated the expression of Bcl-2, matrix macromolecules (aggrecan and collagen II) and NP cell markers (glypican-3, CAXII and keratin-19) compared with 2% deformation compression. Additionally, N-CDH overexpression attenuated the effects of 20% deformation compression on NP cell biology in relation to the designated parameters. N-CDH helps to restore the cell viability, matrix biosynthesis and cellular phenotype of NP cells under high-magnitude compression. © 2017 The Author(s). Published by S. Karger AG, Basel.

  8. The A Theory Of Magnitude (ATOM) model in temporal perception and reproduction tasks.

    Science.gov (United States)

    Fabbri, Marco; Cancellieri, Jennifer; Natale, Vincenzo

    2012-01-01

    According to the A Theory of Magnitude (ATOM) model, time, numbers and space are processed by a common analog magnitude system. The model proposes that time, numbers and space are influenced by each other. Indeed, spatial-temporal (STEARC effect), spatial-numerical (SNARC effect) and temporal-numerical (TiNARC effect) interactions have been observed. However, the processing of time, numbers and space has not yet been studied within the same experimental procedure. The goal of this study is to test the ATOM model using a procedure in which time, numbers and space are all present. The participants were asked to perform temporal estimation (Experiment 1) and reproduction (Experiment 2) tasks in two different conditions, with either numbers or letters as stimuli. In Experiment 1, significant STEARC, SNARC and TiNARC effects were found in general and when numbers were presented. Moreover, a significant triple interaction between space, time and magnitude was observed, indicating associations between the left key, short duration and small magnitudes, as well as between the right key, long duration and large magnitudes. These results were similar in reaction times and accuracy. In Experiment 2, the results of reproduction times mirrored the previous data but the triple interaction was not found on reproduction times. Considering the temporal accuracy, the STEARC, SNARC and TiNARC effects as well as triple interaction were found. The results seem to partially confirm the ATOM model, even if differences between temporal tasks should be posited. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Availability of high-magnitude streamflow for groundwater banking in the Central Valley, California

    Science.gov (United States)

    Kocis, Tiffany N.; Dahlke, Helen E.

    2017-08-01

    California’s climate is characterized by the largest precipitation and streamflow variability observed within the conterminous US This, combined with chronic groundwater overdraft of 0.6-3.5 km3 yr-1, creates the need to identify additional surface water sources available for groundwater recharge using methods such as agricultural groundwater banking, aquifer storage and recovery, and spreading basins. High-magnitude streamflow, i.e. flow above the 90th percentile, that exceeds environmental flow requirements and current surface water allocations under California water rights, could be a viable source of surface water for groundwater banking. Here, we present a comprehensive analysis of the magnitude, frequency, duration and timing of high-magnitude streamflow (HMF) for 93 stream gauges covering the Sacramento, San Joaquin and Tulare basins in California. The results show that in an average year with HMF approximately 3.2 km3 of high-magnitude flow is exported from the entire Central Valley to the Sacramento-San Joaquin Delta often at times when environmental flow requirements of the Delta and major rivers are exceeded. High-magnitude flow occurs, on average, during 7 and 4.7 out of 10 years in the Sacramento River and the San Joaquin-Tulare Basins, respectively, from just a few storm events (5-7 1-day peak events) lasting for 25-30 days between November and April. The results suggest that there is sufficient unmanaged surface water physically available to mitigate long-term groundwater overdraft in the Central Valley.

  10. A comprehensive analysis of high-magnitude streamflow and trends in the Central Valley, California

    Science.gov (United States)

    Kocis, T. N.; Dahlke, H. E.

    2017-12-01

    California's climate is characterized by the largest precipitation and streamflow variability observed within the conterminous US. This, combined with chronic groundwater overdraft of 0.6-3.5 km3 yr-1, creates the need to identify additional surface water sources available for groundwater recharge using methods such as agricultural groundwater banking, aquifer storage and recovery, and spreading basins. High-magnitude streamflow, i.e. flow above the 90th percentile, that exceeds environmental flow requirements and current surface water allocations under California water rights, could be a viable source of surface water for groundwater banking. Here, we present a comprehensive analysis of the magnitude, frequency, duration and timing of high-magnitude streamflow (HMF "metrics") over multiple time periods for 93 stream gauges covering the Sacramento, San Joaquin and Tulare basins in California. In addition, we present trend analyses conducted on the same dataset and all HMF metrics using generalized additive models, the Mann-Kendall trend test, and the Signal to Noise Ratio test. The results of the comprehensive analysis show, in short, that in an average year with HMF approximately 3.2 km3 of high-magnitude flow is exported from the entire Central Valley to the Sacramento-San Joaquin Delta, often at times when environmental flow requirements of the Delta and major rivers are exceeded. High-magnitude flow occurs, on average, during 7 and 4.7 out of 10 years in the Sacramento River and the San Joaquin-Tulare Basins, respectively, from just a few storm events (5-7 1-day peak events) lasting for a total of 25-30 days between November and April. Preliminary trend tests suggest that all HMF metrics show limited change over the last 50 years. As a whole, the results suggest that there is sufficient unmanaged surface water physically available to mitigate long-term groundwater overdraft in the Central Valley.

  11. A Bayesian framework for estimating moment magnitude and its uncertainty from macroseismic intensity measures

    Science.gov (United States)

    Kawabata, E.; Main, I. G.; Naylor, M.; Chandler, R. E.

    2016-12-01

    In moderate to low seismicity areas such as the UK, earthquakes represent a small but not negligible risk to sensitive structures such as nuclear power plants. As a part of the safety case in the planning and regulation of such structures, seismic activity must first be monitored and quantified to form a catalogue of past events. In a low or moderate seismicity zone, most of our knowledge of the most significant events comes from macroseismic intensity measures from the pre-instrumental period (before 1900). These historical records must then be combined and calibrated with modern analogue and digitally-recorded instrumental data on a common source magnitude scale, the most useful of which is the moment magnitude. The result is a unified catalogue that can be used for probabilistic seismic hazard analysis. An isoseismal map involves a set of contours that enclose the areas at which the event was felt at particular intensity values or higher, called felt areas. It has been common practice to draw these contours by hand with varying degrees of subjectivity. Here, we demonstrate a Bayesian method for constructing such maps objectively from macroseismic intensity measures and their observed locations. It involves using mathematical expressions to represent concentric ellipses and estimating their optimal parameters and uncertainties in a Bayesian framework. Inferred fault orientations in the UK are predominantly vertical, so the elliptical assumption is reasonable at least to first order or as a null hypothesis. Relevant physical constraints are used as priors where available. The resulting posterior distributions are used to calculate felt area at a given intensity, as well as a probability density function for the inferred epicentre. We then describe another Bayesian approach for deriving moment magnitude from felt areas based on their relationship and known constraints such as the frequency-magnitude distribution. The use of Bayesian inference allows us to quantify

  12. Weber's law, the magnitude effect and discrimination of sugar concentrations in nectar-feeding animals.

    Science.gov (United States)

    Nachev, Vladislav; Stich, Kai Petra; Winter, York

    2013-01-01

    Weber's law quantifies the perception of difference between stimuli. For instance, it can explain why we are less likely to detect the removal of three nuts from a bowl if the bowl is full than if it is nearly empty. This is an example of the magnitude effect - the phenomenon that the subjective perception of a linear difference between a pair of stimuli progressively diminishes when the average magnitude of the stimuli increases. Although discrimination performances of both human and animal subjects in various sensory modalities exhibit the magnitude effect, results sometimes systematically deviate from the quantitative predictions based on Weber's law. An attempt to reformulate the law to better fit data from acoustic discrimination tasks has been dubbed the "near-miss to Weber's law". Here, we tested the gustatory discrimination performance of nectar-feeding bats (Glossophaga soricina), in order to investigate whether the original version of Weber's law accurately predicts choice behavior in a two-alternative forced choice task. As expected, bats either preferred the sweeter of the two options or showed no preference. In 4 out of 6 bats the near-miss to Weber's law provided a better fit and Weber's law underestimated the magnitude effect. In order to test the generality of this observation in nectar-feeders, we reviewed previously published data on bats, hummingbirds, honeybees, and bumblebees. In all groups of animals the near-miss to Weber's law provided better fits than Weber's law. Furthermore, whereas the magnitude effect was stronger than predicted by Weber's law in vertebrates, it was weaker than predicted in insects. Thus nectar-feeding vertebrates and insects seem to differ in how their choice behavior changes as sugar concentration is increased. We discuss the ecological and evolutionary implications of the observed patterns of sugar concentration discrimination.

  13. Weber's law, the magnitude effect and discrimination of sugar concentrations in nectar-feeding animals.

    Directory of Open Access Journals (Sweden)

    Vladislav Nachev

    Full Text Available Weber's law quantifies the perception of difference between stimuli. For instance, it can explain why we are less likely to detect the removal of three nuts from a bowl if the bowl is full than if it is nearly empty. This is an example of the magnitude effect - the phenomenon that the subjective perception of a linear difference between a pair of stimuli progressively diminishes when the average magnitude of the stimuli increases. Although discrimination performances of both human and animal subjects in various sensory modalities exhibit the magnitude effect, results sometimes systematically deviate from the quantitative predictions based on Weber's law. An attempt to reformulate the law to better fit data from acoustic discrimination tasks has been dubbed the "near-miss to Weber's law". Here, we tested the gustatory discrimination performance of nectar-feeding bats (Glossophaga soricina, in order to investigate whether the original version of Weber's law accurately predicts choice behavior in a two-alternative forced choice task. As expected, bats either preferred the sweeter of the two options or showed no preference. In 4 out of 6 bats the near-miss to Weber's law provided a better fit and Weber's law underestimated the magnitude effect. In order to test the generality of this observation in nectar-feeders, we reviewed previously published data on bats, hummingbirds, honeybees, and bumblebees. In all groups of animals the near-miss to Weber's law provided better fits than Weber's law. Furthermore, whereas the magnitude effect was stronger than predicted by Weber's law in vertebrates, it was weaker than predicted in insects. Thus nectar-feeding vertebrates and insects seem to differ in how their choice behavior changes as sugar concentration is increased. We discuss the ecological and evolutionary implications of the observed patterns of sugar concentration discrimination.

  14. Magnitude and Rupture Area Scaling Relationships of Seismicity at The Northwest Geysers EGS Demonstration Project

    Science.gov (United States)

    Dreger, D. S.; Boyd, O. S.; Taira, T.; Gritto, R.

    2017-12-01

    Enhanced Geothermal System (EGS) resource development requires knowledge of subsurface physical parameters to quantify the evolution of fracture networks. Spatio-temporal source properties, including source dimension, rupture area, slip, rupture speed, and slip velocity of induced seismicity are of interest at The Geysers geothermal field, northern California to map the coseismic facture density of the EGS swarm. In this investigation we extend our previous finite-source analysis of selected M>4 earthquakes to examine source properties of smaller magnitude seismicity located in the Northwest Geysers Enhanced Geothermal System (EGS) demonstration project. Moment rate time histories of the source are found using empirical Green's function (eGf) deconvolution using the method of Mori (1993) as implemented by Dreger et al. (2007). The moment rate functions (MRFs) from data recorded using the Lawrence Berkeley National Laboratory (LBNL) short-period geophone network are inverted for finite-source parameters including the spatial distribution of fault slip, rupture velocity, and the orientation of the causative fault plane. The results show complexity in the MRF for the studied earthquakes. Thus far the estimated rupture area and the magnitude-area trend of the smaller magnitude Geysers seismicity is found to agree with the empirical relationships of Wells and Coppersmith (1994) and Leonard (2010), which were developed for much larger M>5.5 earthquakes worldwide indicating self-similar behavior extending to M2 earthquakes. We will present finite-source inversion results of the micro-earthquakes, attempting to extend the analysis to sub Mw, and demonstrate their magnitude-area scaling. The extension of the scaling laws will then enable the mapping of coseismic fracture density of the EGS swarm in the Northwest Geysers based on catalog moment magnitude estimates.

  15. Magnitude and Correlates of Low Birth Weight at Term in Rural Wardha, Central India

    Directory of Open Access Journals (Sweden)

    Kumar V

    2016-05-01

    Full Text Available Introduction: Birth weight is one of the most important determinant of the neonatal and infant survival. The goal of reducing low birth weight incidence by at least one third between 2000 and 2010 was one of the major goals in ‘A World Fit for Children’. The prevention of low birth weight is a public health priority, particularly in developing countries with high magnitude. Knowledge regarding magnitude and correlates help prevent the condition. Hence, the present study was carried out to study the magnitude and the correlates of low birth weight. Methodology: Two hundred and six newborn babies were recruited on a birth cohort from two Primary Health Centres (PHC of Wardha district to study growth in first year of life. Here, we present the baseline analysis of 172 children who were born full term to study the correlates of low birth weight babies born full term. The children were recruited within first week of their birth. Data was collected on socio-demographic profile, birth history, and maternal characteristics. Proportion of low birth weight was expressed in percentage along with 95% confidence interval. Univariate and multivariate logistic regression was used to study the correlates. Findings are expressed in odds ratios with their 95% confidence intervals. Results: The magnitude of low birth weight at term was found to be 33.1% (95% CI: 26.4%-40.4%. On univariate analysis, significant correlates of low birth weight were consumption of less than 50 iron-folic acid tables and being born to than mother. On multivariate analysis, the significant correlates were female sex of child (OR=2.856, being born to thin mother (OR=5.320, consumption of less than 50 tablets (OR=4.648, and complications of pregnancy (OR=2.917. Conclusions: The magnitude of low birth weight is very high and modifiable correlates of low birth weight are nutritional status of mother, lower consumption of IFA tablets and complications of pregnancy.

  16. Causality between expansion of seismic cloud and maximum magnitude of induced seismicity in geothermal field

    Science.gov (United States)

    Mukuhira, Yusuke; Asanuma, Hiroshi; Ito, Takatoshi; Häring, Markus

    2016-04-01

    Occurrence of induced seismicity with large magnitude is critical environmental issues associated with fluid injection for shale gas/oil extraction, waste water disposal, carbon capture and storage, and engineered geothermal systems (EGS). Studies for prediction of the hazardous seismicity and risk assessment of induced seismicity has been activated recently. Many of these studies are based on the seismological statistics and these models use the information of the occurrence time and event magnitude. We have originally developed physics based model named "possible seismic moment model" to evaluate seismic activity and assess seismic moment which can be ready to release. This model is totally based on microseismic information of occurrence time, hypocenter location and magnitude (seismic moment). This model assumes existence of representative parameter having physical meaning that release-able seismic moment per rock volume (seismic moment density) at given field. Seismic moment density is to be estimated from microseismic distribution and their seismic moment. In addition to this, stimulated rock volume is also inferred by progress of microseismic cloud at given time and this quantity can be interpreted as the rock volume which can release seismic energy due to weakening effect of normal stress by injected fluid. Product of these two parameters (equation (1)) provide possible seismic moment which can be released from current stimulated zone as a model output. Difference between output of this model and observed cumulative seismic moment corresponds the seismic moment which will be released in future, based on current stimulation conditions. This value can be translated into possible maximum magnitude of induced seismicity in future. As this way, possible seismic moment can be used to have feedback to hydraulic stimulation operation in real time as an index which can be interpreted easily and intuitively. Possible seismic moment is defined as equation (1), where D

  17. Optimising 4-D surface change detection: an approach for capturing rockfall magnitude-frequency

    Science.gov (United States)

    Williams, Jack G.; Rosser, Nick J.; Hardy, Richard J.; Brain, Matthew J.; Afana, Ashraf A.

    2018-02-01

    We present a monitoring technique tailored to analysing change from near-continuously collected, high-resolution 3-D data. Our aim is to fully characterise geomorphological change typified by an event magnitude-frequency relationship that adheres to an inverse power law or similar. While recent advances in monitoring have enabled changes in volume across more than 7 orders of magnitude to be captured, event frequency is commonly assumed to be interchangeable with the time-averaged event numbers between successive surveys. Where events coincide, or coalesce, or where the mechanisms driving change are not spatially independent, apparent event frequency must be partially determined by survey interval.The data reported have been obtained from a permanently installed terrestrial laser scanner, which permits an increased frequency of surveys. Surveying from a single position raises challenges, given the single viewpoint onto a complex surface and the need for computational efficiency associated with handling a large time series of 3-D data. A workflow is presented that optimises the detection of change by filtering and aligning scans to improve repeatability. An adaptation of the M3C2 algorithm is used to detect 3-D change to overcome data inconsistencies between scans. Individual rockfall geometries are then extracted and the associated volumetric errors modelled. The utility of this approach is demonstrated using a dataset of ˜ 9 × 103 surveys acquired at ˜ 1 h intervals over 10 months. The magnitude-frequency distribution of rockfall volumes generated is shown to be sensitive to monitoring frequency. Using a 1 h interval between surveys, rather than 30 days, the volume contribution from small (< 0.1 m3) rockfalls increases from 67 to 98 % of the total, and the number of individual rockfalls observed increases by over 3 orders of magnitude. High-frequency monitoring therefore holds considerable implications for magnitude-frequency derivatives, such as hazard return

  18. Quantifying in situ stress magnitudes and orientations for Forsmark. Forsmark stage 2.2

    International Nuclear Information System (INIS)

    Martin, C. Derek

    2007-11-01

    Stephansson et al. concluded that in the Fennoscandia shield: (1) there is a large horizontal stress component in the uppermost 1,000 m of bedrock, and (2) the maximum and minimum horizontal stresses exceed the vertical stress assuming the vertical stress is estimated from the weight of the overburden. Several stress campaigns involving both overcoring and hydraulic fracturing, including the hydraulic testing of pre-existing fractures (HTPF), have been carried out at Forsmark to establish the in situ stress state. The results from the initial campaigns were summarised by Sjoeberg et al. which formed the bases for the stresses provided in the Site Descriptive Model version 1.2. Since then additional stress measurement campaigns have been completed. The results from these stress measurement campaigns support the conclusions from Stephansson et al. In addition to these in situ stress measurements the following additional studies were undertaken to aid in assessing the stress state at Forsmark. 1. A detailed televiewer survey of approximately 6,900 m of borehole walls to depths of 1,000 m was carried out to assess borehole wall damage, i.e. borehole breakouts. 2. Evaluation of nonlinear strains in laboratory samples to depths of approximately 800 m to assess if stress magnitudes were sufficient to create stress-induced microcracking. 3. Assessment of the magnitudes required to cause core disking and survey of core disking observed at Forsmark. The magnitudes and orientations from the stress measurement campaigns were analysed to establish the most likely stress magnitudes and orientations for Design Step D2 within the Target Area of the Complete Site Investigations. The maximum and minimum horizontal stress components are essentially the same as the maximum and intermediate principal stresses, σ1 and σ2, respectively. The minimum principal stress (σ3) is synonymous with the vertical stress. The most likely range in values to be used in the design is also shown. The

  19. Quantifying in situ stress magnitudes and orientations for Forsmark. Forsmark stage 2.2

    Energy Technology Data Exchange (ETDEWEB)

    Martin, C. Derek (Univ. of Alberta (Canada))

    2007-11-15

    Stephansson et al. concluded that in the Fennoscandia shield: (1) there is a large horizontal stress component in the uppermost 1,000 m of bedrock, and (2) the maximum and minimum horizontal stresses exceed the vertical stress assuming the vertical stress is estimated from the weight of the overburden. Several stress campaigns involving both overcoring and hydraulic fracturing, including the hydraulic testing of pre-existing fractures (HTPF), have been carried out at Forsmark to establish the in situ stress state. The results from the initial campaigns were summarised by Sjoeberg et al. which formed the bases for the stresses provided in the Site Descriptive Model version 1.2. Since then additional stress measurement campaigns have been completed. The results from these stress measurement campaigns support the conclusions from Stephansson et al. In addition to these in situ stress measurements the following additional studies were undertaken to aid in assessing the stress state at Forsmark. 1. A detailed televiewer survey of approximately 6,900 m of borehole walls to depths of 1,000 m was carried out to assess borehole wall damage, i.e. borehole breakouts. 2. Evaluation of nonlinear strains in laboratory samples to depths of approximately 800 m to assess if stress magnitudes were sufficient to create stress-induced microcracking. 3. Assessment of the magnitudes required to cause core disking and survey of core disking observed at Forsmark. The magnitudes and orientations from the stress measurement campaigns were analysed to establish the most likely stress magnitudes and orientations for Design Step D2 within the Target Area of the Complete Site Investigations. The maximum and minimum horizontal stress components are essentially the same as the maximum and intermediate principal stresses, sigma1 and sigma2, respectively. The minimum principal stress (sigma3) is synonymous with the vertical stress. The most likely range in values to be used in the design is also

  20. A new dataset of Wood Anderson magnitude from the Trieste (Italy) seismic station

    Science.gov (United States)

    Sandron, Denis; Gentile, G. Francesco; Gentili, Stefania; Rebez, Alessandro; Santulin, Marco; Slejko, Dario

    2014-05-01

    The standard torsion Wood Anderson (WA) seismograph owes its fame to the fact that historically it has been used for the definition of the magnitude of an earthquake (Richter, 1935). With the progress of the technology, digital broadband (BB) seismographs replaced it. However, for historical consistency and homogeneity with the old seismic catalogues, it is still important continuing to compute the so called Wood Anderson magnitude. In order to evaluate WA magnitude, the synthetic seismograms WA equivalent are simulated convolving the waveforms recorded by a BB instrument with a suitable transfer function. The value of static magnification that should be applied in order to simulate correctly the WA instrument is debated. The original WA instrument in Trieste operated from 1971 to 1992 and the WA magnitude (MAW) estimates were regularly reported in the seismic station bulletins. The calculation of the local magnitude was performed following the Richter's formula (Richter, 1935), using the table of corrections factor unmodified from those calibrated for California and without station correction applied (Finetti, 1972). However, the WA amplitudes were computed as vector sum rather than arithmetic average of the horizontal components, resulting in a systematic overestimation of approximately 0.25, depending on the azimuth. In this work, we have retrieved the E-W and N-S components of the original recordings and re-computed MAW according to the original Richter (1935) formula. In 1992, the WA recording were stopped, due to the long time required for the daily development of the photographic paper, the costs of the photographic paper and the progress of the technology. After a decade of interruption, the WA was recovered and modernized by replacing the recording on photographic paper with an electronic device and it continues presently to record earthquakes. The E-W and N-S components records were memorized, but not published till now. Since 2004, next to the WA (few

  1. Scaling A Moment-Rate Function For Small To Large Magnitude Events

    Science.gov (United States)

    Archuleta, Ralph; Ji, Chen

    2017-04-01

    Since the 1980's seismologists have recognized that peak ground acceleration (PGA) and peak ground velocity (PGV) scale differently with magnitude for large and moderate earthquakes. In a recent paper (Archuleta and Ji, GRL 2016) we introduced an apparent moment-rate function (aMRF) that accurately predicts the scaling with magnitude of PGA, PGV, PWA (Wood-Anderson Displacement) and the ratio PGA/2πPGV (dominant frequency) for earthquakes 3.3 ≤ M ≤ 5.3. This apparent moment-rate function is controlled by two temporal parameters, tp and td, which are related to the time for the moment-rate function to reach its peak amplitude and the total duration of the earthquake, respectively. These two temporal parameters lead to a Fourier amplitude spectrum (FAS) of displacement that has two corners in between which the spectral amplitudes decay as 1/f, f denotes frequency. At higher or lower frequencies, the FAS of the aMRF looks like a single-corner Aki-Brune omega squared spectrum. However, in the presence of attenuation the higher corner is almost certainly masked. Attempting to correct the spectrum to an Aki-Brune omega-squared spectrum will produce an "apparent" corner frequency that falls between the double corner frequency of the aMRF. We reason that the two corners of the aMRF are the reason that seismologists deduce a stress drop (e.g., Allmann and Shearer, JGR 2009) that is generally much smaller than the stress parameter used to produce ground motions from stochastic simulations (e.g., Boore, 2003 Pageoph.). The presence of two corners for the smaller magnitude earthquakes leads to several questions. Can deconvolution be successfully used to determine scaling from small to large earthquakes? Equivalently will large earthquakes have a double corner? If large earthquakes are the sum of many smaller magnitude earthquakes, what should the displacement FAS look like for a large magnitude earthquake? Can a combination of such a double-corner spectrum and random

  2. Magnitudes and Moment-Duration Scaling of Low-Frequency Earthquakes Beneath Southern Vancouver Island

    Science.gov (United States)

    Bostock, M. G.; Thomas, A.; Rubin, A. M.; Savard, G.; Chuang, L. Y.

    2015-12-01

    We employ 130 low-frequency-earthquake (LFE) templates representing tremor sources on the plate boundary below southern Vancouver Island to examine LFE magnitudes. Each template is assembled from 100's to 1000's of individual LFEs, representing over 300,000 independent detections from major episodic-tremor-and- slip (ETS) events between 2003 and 2013. Template displacement waveforms for direct P- and S-waves at near epicentral distances are remarkably simple at many stations, approaching the zero-phase, single pulse expected for a point dislocation source in a homogeneous medium. High spatio-temporal precision of template match-filtered detections facilitates precise alignment of individual LFE detections and analysis of waveforms. Upon correction for 1-D geometrical spreading, attenuation, free-surface magnification and radiation pattern, we solve a large, sparse linear system for 3-D path corrections and LFE magnitudes for all detections corresponding to a single ETS template. The spatio-temporal distribution of magnitudes indicates that typically half the total moment release occurs within the first 12-24 hours of LFE activity during an ETS episode when tidal sensitity is low. The remainder is released in bursts over several days, particularly as spatially extensive RTRs, during which tidal sensitivity is high. RTR's are characterized by large magnitude LFEs, and are most strongly expressed in the updip portions of the ETS transition zone and less organized at downdip levels. LFE magnitude-frequency relations are better described by power-law than exponential distributions although they exhibit very high b-values ≥ 6. We examine LFE moment-duration scaling by generating templates using detections for limiting magnitude ranges MW<1.5, MW≥ 2.0. LFE duration displays a weaker dependence upon moment than expected for self-similarity, suggesting that LFE asperities are limited in dimension and that moment variation is dominated by slip. This behaviour implies

  3. Determining on-fault magnitude distributions for a connected, multi-fault system

    Science.gov (United States)

    Geist, E. L.; Parsons, T.

    2017-12-01

    A new method is developed to determine on-fault magnitude distributions within a complex and connected multi-fault system. A binary integer programming (BIP) method is used to distribute earthquakes from a 10 kyr synthetic regional catalog, with a minimum magnitude threshold of 6.0 and Gutenberg-Richter (G-R) parameters (a- and b-values) estimated from historical data. Each earthquake in the synthetic catalog can occur on any fault and at any location. In the multi-fault system, earthquake ruptures are allowed to branch or jump from one fault to another. The objective is to minimize the slip-rate misfit relative to target slip rates for each of the faults in the system. Maximum and minimum slip-rate estimates around the target slip rate are used as explicit constraints. An implicit constraint is that an earthquake can only be located on a fault (or series of connected faults) if it is long enough to contain that earthquake. The method is demonstrated in the San Francisco Bay area, using UCERF3 faults and slip-rates. We also invoke the same assumptions regarding background seismicity, coupling, and fault connectivity as in UCERF3. Using the preferred regional G-R a-value, which may be suppressed by the 1906 earthquake, the BIP problem is deemed infeasible when faults are not connected. Using connected faults, however, a solution is found in which there is a surprising diversity of magnitude distributions among faults. In particular, the optimal magnitude distribution for earthquakes that participate along the Peninsula section of the San Andreas fault indicates a deficit of magnitudes in the M6.0- 7.0 range. For the Rodgers Creek-Hayward fault combination, there is a deficit in the M6.0- 6.6 range. Rather than solving this as an optimization problem, we can set the objective function to zero and solve this as a constraint problem. Among the solutions to the constraint problem is one that admits many more earthquakes in the deficit magnitude ranges for both faults

  4. Far-field tsunami magnitude determined from ocean-bottom pressure gauge data around Japan

    Science.gov (United States)

    Baba, T.; Hirata, K.; Kaneda, Y.

    2003-12-01

    \\hspace*{3mm}Tsunami magnitude is the most fundamental parameter to scale tsunamigenic earthquakes. According to Abe (1979), the tsunami magnitude, Mt, is empirically related to the crest to trough amplitude, H, of the far-field tsunami wave in meters (Mt = logH + 9.1). Here we investigate the far-field tsunami magnitude using ocean-bottom pressure gauge data. The recent ocean-bottom pressure measurements provide more precise tsunami data with a high signal-to-noise ratio. \\hspace*{3mm}Japan Marine Science and Technology Center is monitoring ocean bottom pressure fluctuations using two submarine cables of depths of 1500 - 2400 m. These geophysical observatory systems are located off Cape Muroto, Southwest Japan, and off Hokkaido, Northern Japan. The ocean-bottom pressure data recorded with the Muroto and Hokkaido systems have been collected continuously since March, 1997 and October, 1999, respectively. \\hspace*{3mm}Over the period from March 1997 to June 2003, we have observed four far-field tsunami signals, generated by earthquakes, on ocean-bottom pressure records. These far-field tsunamis were generated by the 1998 Papua New Guinea eq. (Mw 7.0), 1999 Vanuatu eq. (Mw 7.2), 2001 Peru eq. (Mw 8.4) and 2002 Papua New Guinea eq. (Mw 7.6). Maximum amplitude of about 30 mm was recorded by the tsunami from the 2001 Peru earthquake. \\hspace*{3mm}Direct application of the Abe's empirical relation to ocean-bottom pressure gauge data underestimates tsunami magnitudes by about an order of magnitude. This is because the Abe's empirical relation was derived only from tsunami amplitudes with coastal tide gauges where tsunami is amplified by the shoaling of topography and the reflection at the coastline. However, these effects do not work for offshore tsunami in deep oceans. In general, amplification due to shoaling near the coastline is governed by the Green's Law, in which the tsunami amplitude is proportional to h-1/4, where h is the water depth. Wave amplitude also is

  5. Relationships between magnitude representation, counting and memory in 4- to 7-year-old children: A developmental study

    Directory of Open Access Journals (Sweden)

    Szűcs Dénes

    2010-02-01

    Full Text Available Abstract Background The development of an evolutionarily grounded analogue magnitude representation linked to the parietal lobes is frequently thought to be a major factor in the arithmetic development of humans. We investigated the relationship between counting and the development of magnitude representation in children, assessing also children's knowledge of number symbols, their arithmetic fact retrieval, their verbal skills, and their numerical and verbal short-term memory. Methods The magnitude representation was tested by a non-symbolic magnitude comparison task. We have perfected previous experimental designs measuring magnitude discrimination skills in 65 children kindergarten (4-7-year-olds by controlling for several variables which were not controlled for in previous similar research. We also used a large number of trials which allowed for running a full factorial ANOVA including all relevant factors. Tests of verbal counting, of short term memory, of number knowledge, of problem solving abilities and of verbal fluency were administered and correlated with performance in the magnitude comparison task. Results and discussion Verbal counting knowledge and performance on simple arithmetic tests did not correlate with non-symbolic magnitude comparison at any age. Older children performed successfully on the number comparison task, showing behavioural patterns consistent with an analogue magnitude representation. In contrast, 4-year-olds were unable to discriminate number independently of task-irrelevant perceptual variables. Sensitivity to irrelevant perceptual features of the magnitude discrimination task was also affected by age, and correlated with memory, suggesting that more general cognitive abilities may play a role in performance in magnitude comparison tasks. Conclusion We conclude that young children are not able to discriminate numerical magnitudes when co-varying physical magnitudes are methodically pitted against number. We

  6. On the use of Gaia magnitudes and new tables of bolometric corrections

    Science.gov (United States)

    Casagrande, L.; VandenBerg, Don A.

    2018-06-01

    The availability of reliable bolometric corrections and reddening estimates, rather than the quality of parallaxes will be one of the main limiting factors in determining the luminosities of a large fraction of Gaia stars. With this goal in mind, we provide Gaia GBP, G, and GRP synthetic photometry for the entire MARCS grid, and test the performance of our synthetic colours and bolometric corrections against space-borne absolute spectrophotometry. We find indication of a magnitude-dependent offset in Gaia DR2 G magnitudes, which must be taken into account in high accuracy investigations. Our interpolation routines are easily used to derive bolometric corrections at desired stellar parameters, and to explore the dependence of Gaia photometry on Teff, log g, {[Fe/H]}, [α /{Fe}] and E(B - V). Gaia colours for the Sun and Vega, and Teff-dependent extinction coefficients, are also provided.

  7. Spectrophotometry of Wolf-Rayet stars - Intrinsic colors and absolute magnitudes

    Science.gov (United States)

    Torres-Dodgen, Ana V.; Massey, Philip

    1988-01-01

    Absolute spectrophotometry of about 10-A resolution in the range 3400-7300 A have been obtained for southern Wolf-Rayet stars, and line-free magnitudes and colors have been constructed. The emission-line contamination in the narrow-band ubvr systems of Westerlund (1966) and Smith (1968) is shown to be small for most WN stars, but to be quite significant for WC stars. It is suggested that the more severe differences in intrinsic color from star to star of the same spectral subtype noted at shorter wavelengths are due to differences in atmospheric extent. True continuum absolute visual magnitudes and intrinsic colors are obtained for the LMC WR stars. The most visually luminous WN6-WN7 stars are found to be located in the core of the 30 Doradus region.

  8. The impact of fraction magnitude knowledge on algebra performance and learning.

    Science.gov (United States)

    Booth, Julie L; Newton, Kristie J; Twiss-Garrity, Laura K

    2014-02-01

    Knowledge of fractions is thought to be crucial for success with algebra, but empirical evidence supporting this conjecture is just beginning to emerge. In the current study, Algebra 1 students completed magnitude estimation tasks on three scales (0-1 [fractions], 0-1,000,000, and 0-62,571) just before beginning their unit on equation solving. Results indicated that fraction magnitude knowledge, and not whole number knowledge, was especially related to students' pretest knowledge of equation solving and encoding of equation features. Pretest fraction knowledge was also predictive of students' improvement in equation solving and equation encoding skills. Students' placement of unit fractions (e.g., those with a numerator of 1) was not especially useful for predicting algebra performance and learning in this population. Placement of non-unit fractions was more predictive, suggesting that proportional reasoning skills might be an important link between fraction knowledge and learning algebra. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Analyses of surface motions caused by the magnitude 9.0 2004 Sumatra earthquake

    DEFF Research Database (Denmark)

    Khan, Shfaqat Abbas; Gudmundsson, Ó.

    The Sumatra, Indonesia, earthquake on December 26th was one of the most devastating earthquakes in history. With a magnitude of Mw = 9.0 it is the forth largest earthquake recorded since 1900. It occurred about one hundred kilometers off the west coast of northern Sumatra, where the relatively thin...... of years. The result was a devastating tsunami hitting coastlines across the Indian Ocean killing more than 225,000 people in Sri Lanka, India, Indonesia, Thailand and Malaysia. An earthquake of this magnitude is expected to involve a displacement on the fault on the order of 10 meters. But, what...... was the actual amplitude of the surface motions that triggered the tsunami? This can be constrained using the amplitudes of elastic waves radiated from the earthquake, or by direct measurements of deformation. Here we present estimates of the deformation based on continuous Global Positioning System (GPS...

  10. Further details on the applicability of Thellier paleointensity method: The effect of magnitude of laboratory field

    Science.gov (United States)

    Morales, Juan; Goguitchaichvili, Avto; Alva-Valdivia, Luis M.; Urrutia-Fucugauchi, Jaime

    2006-06-01

    Twenty years after Tanaka and Kono's pioneering contribution (Tanaka and Kono, 1984), we give some new details on the effect of applied field strength during Thellier paleointensity experiments. Special attention is paid to the relation of magnitude of laboratory field and Coe's quality factors (Coe et al., 1978). Full thermoremanent magnetizations were imparted on natural samples containing low-Ti titanomagnetites of pseudo-single domain structure in a 40-μT magnetic field from 600 °C to room temperature. The samples were subjected to the routine Thellier procedure using a wide range of applied laboratory fields. Results indicate that values of laboratory fields may be accurately reproduced within 2% of standard error. The quality factors, however, decrease when the magnitude of 'ancient' field does not match to applied laboratory fields. To cite this article: J. Morales et al., C. R. Geoscience 338 (2006).

  11. The Effects of Control of Resources on Magnitudes of Sex Differences in Human Mate Preferences

    Directory of Open Access Journals (Sweden)

    Fhionna Moore

    2010-10-01

    Full Text Available We tested the hypothesis that magnitudes of sex differences in human mate preferences would be inversely related to control of resources. Specifically, we predicted that the ideal partner age, maximum and minimum partner ages tolerated and preferences for “physical attractiveness” over “good financial prospects” of female participants would approach parity with that of men with increasing control of resources. In a sample of 3770 participants recruited via an online survey, the magnitudes of sex differences in age preferences increased with resource control whereas the sex difference in preferences for “physical attractiveness” over “good financial prospects” disappeared when resource control was high. Results are inconsistent, and are discussed in the context of adaptive tradeoff and biosocial models of sex differences in human mate preferences.

  12. Structural response of full-scale concrete bridges subjected to high load magnitudes

    DEFF Research Database (Denmark)

    Halding, Philip Skov; Schmidt, Jacob Wittrup; Jensen, Thomas Westergaard

    -shaped concrete elements. The test method is outlined in the paper, which includes a description of a novel test-rig used to apply a high magnitude loading. It was shown that the test rig could perform controlled testing in only one day, which is an important aspect, since available time (due to traffic...... disturbance) often is an issue when testing on site. Also, different types of measuring equipment such as lasers, LVDT’s and DIC-cameras was investigated, in order to evaluate the deformations during loading of one of the OT-beam bridges. The monitoring equipment was studied to verify if such equipment...... efficiently could be used for in-situ measurements. The load was applied semi-deformation controlled by a combination of dead load and hydraulic jacks. The novel high magnitude loading-rig worked well. It was also possible to achieve good readings from the monitoring equipment in combination with the applied...

  13. An Application of the Coherent Noise Model for the Prediction of Aftershock Magnitude Time Series

    Directory of Open Access Journals (Sweden)

    Stavros-Richard G. Christopoulos

    2017-01-01

    Full Text Available Recently, the study of the coherent noise model has led to a simple (binary prediction algorithm for the forthcoming earthquake magnitude in aftershock sequences. This algorithm is based on the concept of natural time and exploits the complexity exhibited by the coherent noise model. Here, using the relocated catalogue from Southern California Seismic Network for 1981 to June 2011, we evaluate the application of this algorithm for the aftershocks of strong earthquakes of magnitude M≥6. The study is also extended by using the Global Centroid Moment Tensor Project catalogue to the case of the six strongest earthquakes in the Earth during the last almost forty years. The predictor time series exhibits the ubiquitous 1/f noise behavior.

  14. Magnitude of flood flows for selected annual exceedance probabilities in Rhode Island through 2010

    Science.gov (United States)

    Zarriello, Phillip J.; Ahearn, Elizabeth A.; Levin, Sara B.

    2012-01-01

    Heavy persistent rains from late February through March 2010 caused severe widespread flooding in Rhode Island that set or nearly set record flows and water levels at many long-term streamgages in the State. In response, the U.S. Geological Survey, in partnership with the Federal Emergency Management Agency, conducted a study to update estimates of flood magnitudes at streamgages and regional equations for estimating flood flows at ungaged locations. This report provides information needed for flood plain management, transportation infrastructure design, flood insurance studies, and other purposes that can help minimize future flood damages and risks. The magnitudes of floods were determined from the annual peak flows at 43 streamgages in Rhode Island (20 sites), Connecticut (14 sites), and Massachusetts (9 sites) using the standard Bulletin 17B log-Pearson type III method and a modification of this method called the expected moments algorithm (EMA) for 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probability (AEP) floods. Annual-peak flows were analyzed for the period of record through the 2010 water year; however, records were extended at 23 streamgages using the maintenance of variance extension (MOVE) procedure to best represent the longest period possible for determining the generalized skew and flood magnitudes. Generalized least square regression equations were developed from the flood quantiles computed at 41 streamgages (2 streamgages in Rhode Island with reported flood quantiles were not used in the regional regression because of regulation or redundancy) and their respective basin characteristics to estimate magnitude of floods at ungaged sites. Of 55 basin characteristics evaluated as potential explanatory variables, 3 were statistically significant—drainage area, stream density, and basin storage. The pseudo-coefficient of determination (pseudo-R2) indicates these three explanatory variables explain 95 to 96 percent of the variance

  15. Apparent luminosity function of galaxies to the twenty-first magnitude

    International Nuclear Information System (INIS)

    Brown, G.S.

    1979-01-01

    Galaxy counts to limiting magnitudes B=17.7 to 21.0 in 13 selected areas in the north galactic polar cap are presented. The photographs were taken with a reducing camera at the Cassegrain focus of the 91 cm and 205 cm reflectors of McDonald Observatory. Both galaxy and star images were counted and recorded. On each plate a few stars and galaxies were marked as representative of the plate limit. Selected brighter galaxies and stars were measured photoelectrically to fix the zero points. The B magnitude limits of each plate for stars and galaxies are obtained by a combination of photoelectric and photographic photometry. The resulting apparent luminosity functions of galaxies and stars are compared with earlier data. Sources of error in the counts are discussed in detail

  16. Floods on small streams in North Carolina, probable magnitude and frequency

    Science.gov (United States)

    Hinson, Herbert G.

    1965-01-01

    The magnitude and frequency of floods are defined regionally for small streams (drainage area, 1 to 150 sq mi) in North Carolina. Composite frequency curves for each of two regions relate the magnitude of the annual flood, in ratio to the mean annual flood, to recurrence intervals of 1.1 to 50 years. In North Carolina, the mean annual flood (Q2.33) is related to drainage area (A) by the following equation: Q2. 33 = GA0.66, where G, the geographic factor, is the product of a statewide coefficient (US) times a correction which reflects differences in basin characteristics. Isograms of the G factor covering the State are presented.

  17. Type Ia Supernova Intrinsic Magnitude Dispersion and the Fitting of Cosmological Parameters

    Science.gov (United States)

    Kim, A. G.

    2011-02-01

    I present an analysis for fitting cosmological parameters from a Hubble diagram of a standard candle with unknown intrinsic magnitude dispersion. The dispersion is determined from the data, simultaneously with the cosmological parameters. This contrasts with the strategies used to date. The advantages of the presented analysis are that it is done in a single fit (it is not iterative), it provides a statistically founded and unbiased estimate of the intrinsic dispersion, and its cosmological-parameter uncertainties account for the intrinsic-dispersion uncertainty. Applied to Type Ia supernovae, my strategy provides a statistical measure to test for subtypes and assess the significance of any magnitude corrections applied to the calibrated candle. Parameter bias and differences between likelihood distributions produced by the presented and currently used fitters are negligibly small for existing and projected supernova data sets.

  18. Numerical magnitude processing in abacus-trained children with superior mathematical ability: an EEG study.

    Science.gov (United States)

    Huang, Jian; Du, Feng-lei; Yao, Yuan; Wan, Qun; Wang, Xiao-Song; Chen, Fei-Yan

    2015-08-01

    Distance effect has been regarded as the best established marker of basic numerical magnitude processes and is related to individual mathematical abilities. A larger behavioral distance effect is suggested to be concomitant with lower mathematical achievement in children. However, the relationship between distance effect and superior mathematical abilities is unclear. One could get superior mathematical abilities by acquiring the skill of abacus-based mental calculation (AMC), which can be used to solve calculation problems with exceptional speed and high accuracy. In the current study, we explore the relationship between distance effect and superior mathematical abilities by examining whether and how the AMC training modifies numerical magnitude processing. Thus, mathematical competencies were tested in 18 abacus-trained children (who accepted the AMC training) and 18 non-trained children. Electroencephalography (EEG) waveforms were recorded when these children executed numerical comparison tasks in both Arabic digit and dot array forms. We found that: (a) the abacus-trained group had superior mathematical abilities than their peers; (b) distance effects were found both in behavioral results and on EEG waveforms; (c) the distance effect size of the average amplitude on the late negative-going component was different between groups in the digit task, with a larger effect size for abacus-trained children; (d) both the behavioral and EEG distance effects were modulated by the notation. These results revealed that the neural substrates of magnitude processing were modified by AMC training, and suggested that the mechanism of the representation of numerical magnitude for children with superior mathematical abilities was different from their peers. In addition, the results provide evidence for a view of non-abstract numerical representation.

  19. Present-day stress magnitude at depth from leak-off tests in Italy

    Science.gov (United States)

    Mariucci, M. T.; Montone, P.; Pierdominici, S.

    2012-04-01

    We present new results from the analysis of leak-off tests, performed in deep oil wells in Italy, to characterize the present-day stress magnitude and regime in the crust. In the last years we have collected a large number of data (more than 500) from different stress indicators, mainly borehole breakouts, earthquake focal mechanisms and fault data, which provided information on the present-day stress orientations. In some areas the tectonic regime has been inferred either from fault plane solutions of M≥4 earthquakes or from stress inversions of smaller earthquakes. Where seismicity lacks, the regime is not well constrained and little or no information on the magnitude of the crustal stresses is available. In order to improve our knowledge in stress regime and its magnitude in Italy, in this work we use the leak-off test technique. Each test is performed at the bottom of an open hole by sealing off a section and then slowly pressurizing with a fluid until hydraulic tensile fractures develop. The minimum horizontal stress is inferred by leak-off pressure record, the vertical stress is computed by rock density data and the maximum horizontal stress is estimated applying a specific formula from the literature. Thanks to ENI S.p.A. (Italian oil company), that kindly provided new well data, we have been able to perform a critical review of our preliminary calculations and to enhance our previous results concerning stress magnitudes. Totally, we have analyzed 192 leak-off tests at depth between 200 and 5400m (average 1800m). In particular, wells are located along the Italian peninsula and in Sicily: most of them are in the Po Plain and along the Apenninic foredeep; few are in southern Apenninic belt and a few tens are in Sicily. After an accurate selection of the most robust results, we better characterize the Italian stress regime at depth.

  20. Climate variability and increase in intensity and magnitude of dengue incidence in Singapore

    OpenAIRE

    Hii, Yien Ling; Rocklöv, Joacim; Ng, Nawi; Tang, Choon Siang; Pang, Fung Yin; Sauerborn, Rainer

    2009-01-01

    Introduction: Dengue is currently a major public health burden in Asia Pacific Region. This study aims to establish an association between dengue incidence, mean temperature and precipitation and further discuss how weather predictors influence the increase in intensity and magnitude of dengue in Singapore during the period 2000-2007. Materials and methods: Weekly dengue incidence data, daily mean temperature and precipitation and the midyear population data in Singapore during 2000-2007 were...

  1. Analysis of color-magnitude diagrams from three large Magellanic Cloud clusters

    International Nuclear Information System (INIS)

    Jones, J.H.

    1985-01-01

    The color-magnitude diagrams of three LMC clusters and a field were derived from photographic and CCD data provided by Dr. P.J. Flower of Clemson University and Dr. R. Schommer of Rutgers University. The photographic data were scanned and converted to intensity images at KPNO. The stellar photometry program RICHFLD was used to measure the raw magnitudes from these images. Problems with the standard sequence on the plate kept the color terms for the photographic data from being well determined. A version of DAOPHOT was installed on the VAX 11/280s at Clemson and was used to measure the magnitudes from the CCD images of NGC 2249. These magnitudes were used to define another photoelectric sequence for the photographic data which were used to determine a well defined transformation into the standard BV system. The CMDs derived from both the photographic and CCD images of NGC 2249 showed a gap near the tip of the MS. This gap was taken to be the period of rapid evolution just after core hydrogen exhaustion. Using a true distance modulus of 18.3 for the LMC and a reddening taken from the literature, an age of 600 +/- 75 million years was found for NGC 2249. Comparing the CMD of SL 889 to that of NGC 2249 gives a similar age for this small LMC cluster. A subgiant branch was identified in the CMD of NGC 2241. Comparison to old metal poor galactic clusters gave an age near 4 billion years, favoring the short distance scale to the LMC

  2. Spatial Variation of Magnitude Scaling Factors During the 2010 Darfield and 2011 Christchurch, New Zealand, Earthquakes

    OpenAIRE

    Carter, William Lake

    2016-01-01

    Magnitude Scaling Factors (MSF) account for the durational effects of strong ground shaking on the inducement of liquefaction within the simplified liquefaction evaluation procedure which is the most commonly used approach for assessing liquefaction potential worldwide. Within the context of the simplified procedure, the spatial variation in the seismic demand imposed on the soil traditionally has been assumed to be solely a function of the spatial variation of the peak amplitude of the groun...

  3. Origin of how steam rockets can reduce space transport cost by orders of magnitude

    International Nuclear Information System (INIS)

    Zuppero, A.; Larson, T.K.; Schnitzler, B.G.; Rice, J.W.; Hill, T.J.; Richins, W.D.; Parlier, L.; Werner, J.E.

    1999-01-01

    A brief sketch shows the origin of why and how thermal rocket propulsion has the unique potential to dramatically reduce the cost of space transportation for most inner solar system missions of interest. Orders of magnitude reduction in cost are apparently possible when compared to all processes requiring electrolysis for the production of rocket fuels or propellants and to all electric propulsion systems. An order of magnitude advantage can be attributed to rocket propellant tank factors associated with storing water propellant, compared to cryogenic liquids. An order of magnitude can also be attributed to the simplicity of the extraction and processing of ice on the lunar surface, into an easily stored, non-cryogenic rocket propellant (water). A nuclear heated thermal rocket can deliver thousands of times its mass to Low Earth Orbit from the Lunar surface, providing the equivalent to orders of magnitude drop in launch cost for mass in Earth orbit. Mass includes water ice. These cost reductions depend (exponentially) on the mission delta-v requirements being less than about 6 km/s, or about 3 times the specific velocity of steam rockets (2 km/s, from Isp 200 sec). Such missions include: from the lunar surface to Low Lunar Orbit, (LLO), from LLO to lunar escape, from Low Earth Orbit (LEO) to Geosynchronous Orbit (GEO), from LEO to Earth Escape, from LEO to Mars Transfer Orbit, from LLO to GEO, missions returning payloads from about 10% of the periodic comets using propulsive capture to orbits around Earth itself, and fast, 100 day missions from Lunar Escape to Mars. All the assertions depend entirely and completely on the existence of abundant, nearly pure ice at the permanently dark North and South Poles of the Moon. copyright 1999 American Institute of Physics

  4. Masses and K-line absolute magnitudes of γ Leonis and 35 Comae

    International Nuclear Information System (INIS)

    Deming, D.; Dykton, M.

    1979-01-01

    The visual binary system γ Leonis consists of two K giants whose total mass was found by Wilson to be less than 0.6M/sub sun/ when a distance was obtained from K-line absolute magnitudes of both components. Since the orbital period of the system is of order 600 years, the orbital solution has usually been regarded as the most likely explanation of the anomalous mass. We have investigated the uniqueness of the orbital solution. We find that the individual orbital elements are only poorly determined, but that a 3 /P 2 is known to within +- 10%. The anomalous mass of this binary system implies either extensive mass-loss or the need for revisions in the K-line absolute magnitudes. We also investigate the binary system 35 Comae. Wilson has noted that in this system the K-line absolute magnitude of the G8 III primary component implies a total mass of 8 M/sub sun/. However the A component of 35 Comae is not sufficiently luminous to justify such a large total mass. The system has a period of order 700 years, and the uniqueness of the orbital solution is therefore suspect. However, in this case also we have investigated the uniqueness of the orbital solution and find that individual orbital elements are poorly determined, but that a 3 /P 2 is known to within +- 17%. We point out that 35 Comae is known to be very metal rich, in contrast to γ Leonis which is metal poor. We conclude that a composition-dependent correction to the K-line absolute magnitudes provides the simplest explanation of these mass anomalies. Such a correction would also give better agreement with the trigonometric parallaxes of these binary systems

  5. Predicting the Maximum Earthquake Magnitude from Seismic Data in Israel and Its Neighboring Countries.

    Science.gov (United States)

    Last, Mark; Rabinowitz, Nitzan; Leonard, Gideon

    2016-01-01

    This paper explores several data mining and time series analysis methods for predicting the magnitude of the largest seismic event in the next year based on the previously recorded seismic events in the same region. The methods are evaluated on a catalog of 9,042 earthquake events, which took place between 01/01/1983 and 31/12/2010 in the area of Israel and its neighboring countries. The data was obtained from the Geophysical Institute of Israel. Each earthquake record in the catalog is associated with one of 33 seismic regions. The data was cleaned by removing foreshocks and aftershocks. In our study, we have focused on ten most active regions, which account for more than 80% of the total number of earthquakes in the area. The goal is to predict whether the maximum earthquake magnitude in the following year will exceed the median of maximum yearly magnitudes in the same region. Since the analyzed catalog includes only 28 years of complete data, the last five annual records of each region (referring to the years 2006-2010) are kept for testing while using the previous annual records for training. The predictive features are based on the Gutenberg-Richter Ratio as well as on some new seismic indicators based on the moving averages of the number of earthquakes in each area. The new predictive features prove to be much more useful than the indicators traditionally used in the earthquake prediction literature. The most accurate result (AUC = 0.698) is reached by the Multi-Objective Info-Fuzzy Network (M-IFN) algorithm, which takes into account the association between two target variables: the number of earthquakes and the maximum earthquake magnitude during the same year.

  6. Spatializing Emotion: No Evidence for a Domain-General Magnitude System.

    Science.gov (United States)

    Pitt, Benjamin; Casasanto, Daniel

    2017-11-22

    People implicitly associate different emotions with different locations in left-right space. Which aspects of emotion do they spatialize, and why? Across many studies people spatialize emotional valence, mapping positive emotions onto their dominant side of space and negative emotions onto their non-dominant side, consistent with theories of metaphorical mental representation. Yet other results suggest a conflicting mapping of emotional intensity (a.k.a., emotional magnitude), according to which people associate more intense emotions with the right and less intense emotions with the left - regardless of their valence; this pattern has been interpreted as support for a domain-general system for representing magnitudes. To resolve the apparent contradiction between these mappings, we first tested whether people implicitly map either valence or intensity onto left-right space, depending on which dimension of emotion they attend to (Experiments 1a, b). When asked to judge emotional valence, participants showed the predicted valence mapping. However, when asked to judge emotional intensity, participants showed no systematic intensity mapping. We then tested an alternative explanation of findings previously interpreted as evidence for an intensity mapping (Experiments 2a, b). These results suggest that previous findings may reflect a left-right mapping of spatial magnitude (i.e., the size of a salient feature of the stimuli) rather than emotion. People implicitly spatialize emotional valence, but, at present, there is no clear evidence for an implicit lateral mapping of emotional intensity. These findings support metaphor theory and challenge the proposal that mental magnitudes are represented by a domain-general metric that extends to the domain of emotion. Copyright © 2017 Cognitive Science Society, Inc.

  7. Building an Ensemble Seismic Hazard Model for the Magnitude Distribution by Using Alternative Bayesian Implementations

    Science.gov (United States)

    Taroni, M.; Selva, J.

    2017-12-01

    In this work we show how we built an ensemble seismic hazard model for the magnitude distribution for the TSUMAPS-NEAM EU project (http://www.tsumaps-neam.eu/). The considered source area includes the whole NEAM region (North East Atlantic, Mediterranean and connected seas). We build our models by using the catalogs (EMEC and ISC), their completeness and the regionalization provided by the project. We developed four alternative implementations of a Bayesian model, considering tapered or truncated Gutenberg-Richter distributions, and fixed or variable b-value. The frequency size distribution is based on the Weichert formulation. This allows for simultaneously assessing all the frequency-size distribution parameters (a-value, b-value, and corner magnitude), using multiple completeness periods for the different magnitudes. With respect to previous studies, we introduce the tapered Pareto distribution (in addition to the classical truncated Pareto), and we build a novel approach to quantify the prior distribution. For each alternative implementation, we set the prior distributions using the global seismic data grouped according to the different types of tectonic setting, and assigned them to the related regions. The estimation is based on the complete (not declustered) local catalog in each region. Using the complete catalog also allows us to consider foreshocks and aftershocks in the seismic rate computation: the Poissonicity of the tsunami events (and similarly the exceedances of the PGA) will be insured by the Le Cam's theorem. This Bayesian approach provides robust estimations also in the zones where few events are available, but also leaves us the possibility to explore the uncertainty associated with the estimation of the magnitude distribution parameters (e.g. with the classical Metropolis-Hastings Monte Carlo method). Finally we merge all the models with their uncertainty to create the ensemble model that represents our knowledge of the seismicity in the

  8. Historical estimates of national accounts magnitudes in Greece: 1830-1939

    OpenAIRE

    Κωστελένος, Γεώργιος Κ.

    2007-01-01

    The study of long run economic development is facilitated immensely by the existence of relevant data. In this context, long run national accounts magnitudes are probably the most important. This has been realized since the early 1950s by economists of the stature of Kuznets, Friedman and North and relevant time series have been estimated, originally for countries like the U.S.A. and Great Britain and subsequently for other developed and less developed countries. In Greece, how...

  9. Magnitude and Surface Rupture Length of Prehistoric Upper Crustal Earthquakes in the Puget Lowland, Washington State

    Science.gov (United States)

    Sherrod, B. L.; Styron, R. H.

    2016-12-01

    Paleoseismic studies documented prehistoric earthquakes after the last glaciation ended 15 ka on 13 upper-crustal fault zones in the Cascadia fore arc. These fault zones are a consequence of north-directed fore arc block migration manifesting as a series of bedrock uplifts and intervening structural basins in the southern Salish Sea lowland between Vancouver, B.C. to the north and Olympia, WA to the south, and bounded on the east and west by the Cascade Mountains and Olympic Mountains, respectively. Our dataset uses published information and includes 27 earthquakes tabulated from observations of postglacial deformation at 63 sites. Stratigraphic offsets along faults consist of two types of measurements: 1) vertical separation of strata along faults observed in fault scarp excavations, and 2) estimates from coastal uplift and subsidence. We used probabilistic methods to estimate past rupture magnitudes and surface rupture length (SRL), applying empirical observations from modern earthquakes and point measurements from paleoseismic sites (Biasi and Weldon, 2006). Estimates of paleoearthquake magnitude ranged between M 6.5 and M 7.5. SRL estimates varied between 20 and 90 km. Paleoearthquakes on the Seattle fault zone and Saddle Mountain West fault about 1100 years ago were outliers in our analysis. Large offsets observed for these two earthquakes implies a M 7.8 and 200 km SRL, given the average observed ratio of slip/SRL in modern earthquakes. The actual mapped traces of these faults are less than 200km, implying these earthquakes had an unusually high static stress drop or, in the case of the Seattle fault, splay faults may have accentuated uplift in the hanging wall. Refined calculations incorporating fault area may change these magnitude and SRL estimates. Biasi, G.P., and Weldon, R.J., 2006, Estimating Surface Rupture Length and Magnitude of Paleoearthquakes from Point Measurements of Rupture Displacement: B. Seismol. Soc. Am., 96, 1612-1623.

  10. Force Maintenance Accuracy Using a Tool: Effects of Magnitude and Feedback.

    Science.gov (United States)

    Wang, Dangxiao; Jiao, Jian; Yang, Gaofeng; Zhang, Yuru

    2016-01-01

    The ability to precisely produce a force via a hand-held tool is crucial in fine manipulations. In this paper, we study the error in maintaining a target force ranging from 0.5 to 5 N under two concurrent feedback conditions: pure haptic feedback (H), and visual plus haptic feedback (V + H). The results show that absolute error (AE) increases along with the increasing force magnitudes under both feedback conditions. For target forces ranging from 1.5 to 5 N, the relative error (RE) is approximately constant under both feedback conditions, while the RE significantly increases for the small target forces of 0.5 and 1 N. The effect of force magnitude on the coefficient of variation (CoV) is not significant for target forces ranging from 1.5 to 5 N. For both the RE and the CoV, the values under the H condition are significantly larger than those under the V + H condition. The effect of manipulation mode (i.e., a hand-held tool or a fingertip) on force maintenance accuracy is complex, i.e., its effect on RE is not significant while its effect on CoV is significant. Only for the magnitude of 0.5 N, the RE of using the tool was significantly greater than that of using the fingertip under both feedback conditions. For both the RE and the CoV, no interaction effect exists between manipulation mode, force magnitude and feedback condition.

  11. Distance to M33 determined from magnitude corrections to Hubble's original cepheid photometry

    International Nuclear Information System (INIS)

    Sandage, A.

    1983-01-01

    New photoelectric photometry in Selected Area 45, and transfers from a faint photoelectric sequence adjacent to the south-preceding arm in M33 have been made to the comparison stars for Hubble's Cepheids in M33. Progressive magnitude corrections are required to Hubble's M33 scales, reaching 2.8 mag at the limit of the Mount Wilson 2.5-m Hooker reflector. Hubble's Cepheid light curves have been corrected to the B photoelectric system, and new photometric parameters are given for 35 of his variables. The P-L relation agrees in zero point to within 0.2 mag of the P-L relation from independent data by Sandage and Carlson for 12 new Cepheids in an outlying region of M33. Application of an adopted absolute P-L relation, calibrated by Martin, Warren, and Feast, to these data gives an apparent blue modulus of (m-M)/sup AB//sub M33/ = 25.35, which is 0.67 mag fainter than a previously adopted value, and represents a factor of 4.2 increase of Hubble's earliest distance. Three consequences of this larger apparent distance modulus are (1) the mean absolute magnitude of the first three brightest red supergiants is M/sup max//sub left-angle-bracketV/(3)> = -8.7 rather than approx.-8.0 in M33, complicating but not destroying use of red supergiants as distance indicators, (2) the mean absolute magnitude of the two brightest blue irregular supergiant variables is M/sub left-angle-bracketB/(2)> = -9.95, which is close to the value for the brightest known supergiants in the galaxy, and (3) the absolute magnitude of M33 itself is brighter than heretofore assumed

  12. Magnitudes and units in radiation protection; Grandeurs et unites en radioprotection

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This sheet provides definition and information on the ionizing radiations, the measurement of a ionizing radiation magnitude by a radioactive source (the becquerel), the measurement of the ionizing radiation energy absorbed by the organism (the gray), the biological impact evaluation of ionizing radiations in function of their nature (the sievert) and the evaluation and comparison of biological risks bond to little doses (dose efficiency). (A.L.B.)

  13. Increased rates of large‐magnitude explosive eruptions in Japan in the late Neogene and Quaternary

    Science.gov (United States)

    Sparks, R. S. J.; Wallace, L. M.; Engwell, S. L.; Scourse, E. M.; Barnard, N. H.; Kandlbauer, J.; Brown, S. K.

    2016-01-01

    Abstract Tephra layers in marine sediment cores from scientific ocean drilling largely record high‐magnitude silicic explosive eruptions in the Japan arc for up to the last 20 million years. Analysis of the thickness variation with distance of 180 tephra layers from a global data set suggests that the majority of the visible tephra layers used in this study are the products of caldera‐forming eruptions with magnitude (M) > 6, considering their distances at the respective drilling sites to their likely volcanic sources. Frequency of visible tephra layers in cores indicates a marked increase in rates of large magnitude explosive eruptions at ∼8 Ma, 6–4 Ma, and further increase after ∼2 Ma. These changes are attributed to major changes in tectonic plate interactions. Lower rates of large magnitude explosive volcanism in the Miocene are related to a strike‐slip‐dominated boundary (and temporary cessation or deceleration of subduction) between the Philippine Sea Plate and southwest Japan, combined with the possibility that much of the arc in northern Japan was submerged beneath sea level partly due to previous tectonic extension of northern Honshu related to formation of the Sea of Japan. Changes in plate motions and subduction dynamics during the ∼8 Ma to present period led to (1) increased arc‐normal subduction in southwest Japan (and resumption of arc volcanism) and (2) shift from extension to compression of the upper plate in northeast Japan, leading to uplift, crustal thickening and favorable conditions for accumulation of the large volumes of silicic magma needed for explosive caldera‐forming eruptions. PMID:27656115

  14. Magnitude and duration of cue-induced craving for marijuana in volunteers with cannabis use disorder.

    Science.gov (United States)

    Lundahl, Leslie H; Greenwald, Mark K

    2016-09-01

    Evaluate magnitude and duration of subjective and physiologic responses to neutral and marijuana (MJ)-related cues in cannabis dependent volunteers. 33 volunteers (17 male) who met DSM-IV criteria for Cannabis Abuse or Dependence were exposed to neutral (first) then MJ-related visual, auditory, olfactory and tactile cues. Mood, drug craving and physiology were assessed at baseline, post-neutral, post-MJ and 15-min post MJ cue exposure to determine magnitude of cue- responses. For a subset of participants (n=15; 9 male), measures of craving and physiology were collected also at 30-, 90-, and 150-min post-MJ cue to examine duration of cue-effects. In cue-response magnitude analyses, visual analog scale (VAS) items craving for, urge to use, and desire to smoke MJ, Total and Compulsivity subscale scores of the Marijuana Craving Questionnaire, anxiety ratings, and diastolic blood pressure (BP) were significantly elevated following MJ vs. neutral cue exposure. In cue-response duration analyses, desire and urge to use MJ remained significantly elevated at 30-, 90- and 150-min post MJ-cue exposure, relative to baseline and neutral cues. Presentation of polysensory MJ cues increased MJ craving, anxiety and diastolic BP relative to baseline and neutral cues. MJ craving remained elevated up to 150-min after MJ cue presentation. This finding confirms that carry-over effects from drug cue presentation must be considered in cue reactivity studies. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  15. Rapid estimation of earthquake magnitude from the arrival time of the peak high‐frequency amplitude

    Science.gov (United States)

    Noda, Shunta; Yamamoto, Shunroku; Ellsworth, William L.

    2016-01-01

    We propose a simple approach to measure earthquake magnitude M using the time difference (Top) between the body‐wave onset and the arrival time of the peak high‐frequency amplitude in an accelerogram. Measured in this manner, we find that Mw is proportional to 2logTop for earthquakes 5≤Mw≤7, which is the theoretical proportionality if Top is proportional to source dimension and stress drop is scale invariant. Using high‐frequency (>2  Hz) data, the root mean square (rms) residual between Mw and MTop(M estimated from Top) is approximately 0.5 magnitude units. The rms residuals of the high‐frequency data in passbands between 2 and 16 Hz are uniformly smaller than those obtained from the lower‐frequency data. Top depends weakly on epicentral distance, and this dependence can be ignored for distances earthquake produces a final magnitude estimate of M 9.0 at 120 s after the origin time. We conclude that Top of high‐frequency (>2  Hz) accelerograms has value in the context of earthquake early warning for extremely large events.

  16. Star/galaxy separation at faint magnitudes: Application to a simulated Dark Energy Survey

    Energy Technology Data Exchange (ETDEWEB)

    Soumagnac, M.T.; et al.

    2013-06-21

    We address the problem of separating stars from galaxies in future large photometric surveys. We focus our analysis on simulations of the Dark Energy Survey (DES). In the first part of the paper, we derive the science requirements on star/galaxy separation, for measurement of the cosmological parameters with the Gravitational Weak Lensing and Large Scale Structure probes. These requirements are dictated by the need to control both the statistical and systematic errors on the cosmological parameters, and by Point Spread Function calibration. We formulate the requirements in terms of the completeness and purity provided by a given star/galaxy classifier. In order to achieve these requirements at faint magnitudes, we propose a new method for star/galaxy separation in the second part of the paper. We first use Principal Component Analysis to outline the correlations between the objects parameters and extract from it the most relevant information. We then use the reduced set of parameters as input to an Artificial Neural Network. This multi-parameter approach improves upon purely morphometric classifiers (such as the classifier implemented in SExtractor), especially at faint magnitudes: it increases the purity by up to 20% for stars and by up to 12% for galaxies, at i-magnitude fainter than 23.

  17. Star/galaxy separation at faint magnitudes: application to a simulated Dark Energy Survey

    Energy Technology Data Exchange (ETDEWEB)

    Soumagnac, M. T.; Abdalla, F. B.; Lahav, O.; Kirk, D.; Sevilla, I.; Bertin, E.; Rowe, B. T. P.; Annis, J.; Busha, M. T.; Da Costa, L. N.; Frieman, J. A.; Gaztanaga, E.; Jarvis, M.; Lin, H.; Percival, W. J.; Santiago, B. X.; Sabiu, C. G.; Wechsler, R. H.; Wolz, L.; Yanny, B.

    2015-04-14

    We address the problem of separating stars from galaxies in future large photometric surveys. We focus our analysis on simulations of the Dark Energy Survey (DES). In the first part of the paper, we derive the science requirements on star/galaxy separation, for measurement of the cosmological parameters with the gravitational weak lensing and large-scale structure probes. These requirements are dictated by the need to control both the statistical and systematic errors on the cosmological parameters, and by point spread function calibration. We formulate the requirements in terms of the completeness and purity provided by a given star/galaxy classifier. In order to achieve these requirements at faint magnitudes, we propose a new method for star/galaxy separation in the second part of the paper. We first use principal component analysis to outline the correlations between the objects parameters and extract from it the most relevant information. We then use the reduced set of parameters as input to an Artificial Neural Network. This multiparameter approach improves upon purely morphometric classifiers (such as the classifier implemented in SExtractor), especially at faint magnitudes: it increases the purity by up to 20 per cent for stars and by up to 12 per cent for galaxies, at i-magnitude fainter than 23.

  18. A Novel Method for Age Estimation in Solar-Type Stars Through GALEX FUV Magnitudes

    Science.gov (United States)

    Ho, Kelly; Subramonian, Arjun; Smith, Graeme; Shouru Shieh

    2018-01-01

    Utilizing an inverse association known to exist between Galaxy Evolution Explorer (GALEX) far ultraviolet (FUV) magnitudes and the chromospheric activity of F, G, and K dwarfs, we explored a method of age estimation in solar-type stars through GALEX FUV magnitudes. Sample solar-type star data were collected from refereed publications and filtered by B-V and absolute visual magnitude to ensure similarities in temperature and luminosity to the Sun. We determined FUV-B and calculated a residual index Q for all the stars, using the temperature-induced upper bound on FUV-B as the fiducial. Plotting current age estimates for the stars against Q, we discovered a strong and significant association between the variables. By applying a log-linear transformation to the data to produce a strong correlation between Q and loge Age, we confirmed the association between Q and age to be exponential. Thus, least-squares regression was used to generate an exponential model relating Q to age in solar-type stars, which can be used by astronomers. The Q-method of stellar age estimation is simple and more efficient than existing spectroscopic methods and has applications to galactic archaeology and stellar chemical composition analysis.

  19. Introduction to the method of average magnitude analysis and application to natural convection in cavities

    International Nuclear Information System (INIS)

    Lykoudis, P.S.

    1995-01-01

    The method of Average Magnitude Analysis is a mixture of the Integral Method and the Order of Magnitude Analysis. The paper shows how the differential equations of conservation for steady-state, laminar, boundary layer flows are converted to a system of algebraic equations, where the result is a sum of the order of magnitude of each term, multiplied by, a weight coefficient. These coefficients are determined from integrals containing the assumed velocity and temperature profiles. The method is illustrated by applying it to the case of drag and heat transfer over an infinite flat plate. It is then applied to the case of natural convection over an infinite flat plate with and without the presence of a horizontal magnetic field, and subsequently to enclosures of aspect ratios of one or higher. The final correlation in this instance yields the Nusselt number as a function of the aspect ratio and the Rayleigh and Prandtl numbers. This correlation is tested against a wide range of small and large values of these parameters. 19 refs., 4 figs

  20. An improvement of drought monitoring through the use of a multivariate magnitude index

    Science.gov (United States)

    Real-Rangel, R. A.; Alcocer-Yamanaka, V. H.; Pedrozo-Acuña, A.; Breña-Naranjo, J. A.; Ocón-Gutiérrez, A. R.

    2017-12-01

    In drought monitoring activities it is widely acknowledged that the severity of an event is determined in relation to monthly values of univariate indices of one or more hydrological variables. Normally, these indices are estimated using temporal windows from 1 to 12 months or more to aggregate the effects of deficits in the variable of interest. However, the use of these temporal windows may lead to a misperception of both, the drought event intensity and the timing of its occurrence. In this context, this work presents the implementation of a trivariate drought magnitude index, considering key hydrological variables (e.g., precipitation, soil moisture and runoff) using for this the framework of the Multivariate Standardized Drought Index (MSDI). Despite the popularity and simplicity of the concept of drought magnitude for standardized drought indices, its implementation in drought monitoring and early warning systems has not been reported. This approach has been tested for operational purposes in the recently launched Multivariate Drought Monitor of Mexico (MOSEMM) and the results shows that the inclusion of a Magnitude index facilitates the drought detection and, thus, improves the decision making process for emergency managers.

  1. Earthquake Magnitude Relationships for the Saint Peter and Saint Paul Archipelago, Equatorial Atlantic

    Science.gov (United States)

    de Melo, Guilherme W. S.; do Nascimento, Aderson F.

    2018-03-01

    We have investigated several relationships between ML, M(NEIC) and Mw for the earthquakes locally recorded in the Saint Peter and Saint Paul Archipelago (SPSPA), Equatorial Atlantic. Because we only have one station in the area, we could not derive attenuation relations for events recorded at different distances at different stations. Our approach was then to compare our ML estimates with magnitudes reported by NEIC. This approach produced acceptable results particularly for epicentral distance smaller than 100 km. For distances greater that 100 km, there is a systematic increase in the residuals probable due to the lack of station correction and our inability to accurately estimate Q. We also investigate the Mw—M(NEIC) relationship. We find that Mw estimates using S-wave produce smaller residuals when compared with both M(NEIC). Finally, we also investigate the ML—Mw relationship and observe that given the data set we have, the 1:1 holds. We believe that the use of the present methodologies provide consistent magnitude estimates between all the magnitudes investigated that could be used to better assess seismic hazard in the region.

  2. Automated method for determining location and magnitude of leaks inside a PWR containment

    International Nuclear Information System (INIS)

    Cho, J.H.; Elia, F.A. Jr.

    1986-01-01

    Thermal-hydraulics analysis can be used to determine location and magnitude of leaks inside a pressurized water reactor (PWR) containment, as required by plant technical specifications. The major advantage of this detection method is that it minimizes radiation exposure of maintenance personnel because most of the leak detection process is performed from the control room outside the containment. In addition, such a program allows for the elimination of pipe whip restraints and jet impingement shields, eliminating costs for maintenance of these supports and shields in older plants and lowering construction costs for new plants. Previously, only simple single-node containment models were used for determining leakage magnitude. This paper presents a more sophisticated multinode approach for determining the magnitude and location. The resulting sensitivities to leak can be programmed into the plant's computer system. In this way, the plant's computer will be able to measure and locate leaks inside containment. The study concludes that dew point temperature (or relative humidity) is the most suitable parameter for locating a leak while flow rate to sump is the most suitable parameter for quantifying the leak

  3. Fixed-head star tracker magnitude calibration on the solar maximum mission

    Science.gov (United States)

    Pitone, Daniel S.; Twambly, B. J.; Eudell, A. H.; Roberts, D. A.

    1990-01-01

    The sensitivity of the fixed-head star trackers (FHSTs) on the Solar Maximum Mission (SMM) is defined as the accuracy of the electronic response to the magnitude of a star in the sensor field-of-view, which is measured as intensity in volts. To identify stars during attitude determination and control processes, a transformation equation is required to convert from star intensity in volts to units of magnitude and vice versa. To maintain high accuracy standards, this transformation is calibrated frequently. A sensitivity index is defined as the observed intensity in volts divided by the predicted intensity in volts; thus, the sensitivity index is a measure of the accuracy of the calibration. Using the sensitivity index, analysis is presented that compares the strengths and weaknesses of two possible transformation equations. The effect on the transformation equations of variables, such as position in the sensor field-of-view, star color, and star magnitude, is investigated. In addition, results are given that evaluate the aging process of each sensor. The results in this work can be used by future missions as an aid to employing data from star cameras as effectively as possible.

  4. The differing magnitude distributions of the two Jupiter Trojan color populations

    Energy Technology Data Exchange (ETDEWEB)

    Wong, Ian; Brown, Michael E. [Division of Geological and Planetary Sciences, California Institute of Technology Pasadena, CA 91125 (United States); Emery, Joshua P., E-mail: iwong@caltech.edu [Department of Earth and Planetary Sciences, University of Tennessee Knoxville, TN 37996 (United States)

    2014-12-01

    The Jupiter Trojans are a significant population of minor bodies in the middle solar system that have garnered substantial interest in recent years. Several spectroscopic studies of these objects have revealed notable bimodalities with respect to near-infrared spectra, infrared albedo, and color, which suggest the existence of two distinct groups among the Trojan population. In this paper, we analyze the magnitude distributions of these two groups, which we refer to as the red and less red color populations. By compiling spectral and photometric data from several previous works, we show that the observed bimodalities are self-consistent and categorize 221 of the 842 Trojans with absolute magnitudes in the range H<12.3 into the two color populations. We demonstrate that the magnitude distributions of the two color populations are distinct to a high confidence level (>95%) and fit them individually to a broken power law, with special attention given to evaluating and correcting for incompleteness in the Trojan catalog as well as incompleteness in our categorization of objects. A comparison of the best-fit curves shows that the faint-end power-law slopes are markedly different for the two color populations, which indicates that the red and less red Trojans likely formed in different locations. We propose a few hypotheses for the origin and evolution of the Trojan population based on the analyzed data.

  5. Saturation of subjective reward magnitude as a function of current and pulse frequency.

    Science.gov (United States)

    Simmons, J M; Gallistel, C R

    1994-02-01

    In rats with electrodes in the medial forebrain bundle, the upper portion of the function relating the experienced magnitude of the reward to pulse frequency was determined at currents ranging from 100 to 1,000 microA. The pulse frequency required to produce an asymptotic level of reward was inversely proportional to current except at the lowest currents and highest pulse frequencies. At a given current, the subjective reward magnitude functions decelerated to an asymptote over an interval in which the pulse frequency doubled or tripled. The asymptotic level of reward was approximately constant for currents between 200 and 1,000 microA but declined substantially at currents at or below 100 microA and pulse frequencies at or above 250 to 400 pulses per second. The results are consistent with the hypothesis that the magnitude of the experienced reward depends only on the number of action potentials generated by the train of pulses in the bundle of reward-relevant axons.

  6. Trunk muscle cocontraction: the effects of moment direction and moment magnitude.

    Science.gov (United States)

    Lavender, S A; Tsuang, Y H; Andersson, G B; Hafezi, A; Shin, C C

    1992-09-01

    This study investigated the cocontraction of eight trunk muscles during the application of asymmetric loads to the torso. External moments of 10, 20, 30, 40, and 50 Nm were applied to the torso via a harness system. The direction of the applied moment was varied by 30 degrees increments to the subjects' right side between the sagittally symmetric orientations front and rear. Electromyographic (EMG) data from the left and right latissimus dorsi, erector spinae, external oblique, and rectus abdominus were collected from 10 subjects. The normalized EMG data were tested using multivariate and univariate analyses of variance procedures. These analyses showed significant interactions between the moment magnitude and the moment direction for seven of the eight muscles. Most of the interactions could be characterized as due to changes in muscle recruitment with changes in the direction of the external moment. Analysis of the relative activation levels, which were computed for each combination of moment magnitude and direction, indicated large changes in muscle recruitment due to asymmetry, but only small adjustments in the relative activation levels due to increased moment magnitude.

  7. Regional relationships among earthquake magnitude scales. Seismic safety margins research program

    International Nuclear Information System (INIS)

    Chung, D.H.; Bernreuter, D.L.

    1980-09-01

    The seismic body-wave magnitude m b of an earthquake is strongly affected by regional variations in the Q structure, composition, and physical state within the earth. Therefore, because of differences in attenuation of P-waves between the western and eastern United States, a problem arises when comparing m b 's for the two regions. A regional m b magnitude bias exists which, depending on where the earthquake occurs and where the P-waves are recorded, can lead to magnitude errors as large as one-third unit. There is also a significant difference between m b and M L values for earthquakes in the western United States. An empirical link between the m b of an eastern U.S. earthquake and the M L of an equivalent western earthquake is given y M L = 0.57 + 0.92(m b ) East . This result is important when comparing ground motion between the two regions and for choosing a set of real western U.S. earthquake records to represent eastern earthquakes. (author)

  8. THE LEO IV DWARF SPHEROIDAL GALAXY: COLOR-MAGNITUDE DIAGRAM AND PULSATING STARS

    International Nuclear Information System (INIS)

    Moretti, Maria Ida; Dall'Ora, Massimo; Ripepi, Vincenzo

    2009-01-01

    We present the first V, B - V color-magnitude diagram of the Leo IV dwarf spheroidal galaxy, a faint Milky Way satellite recently discovered by the Sloan Digital Sky Survey. We have obtained B, V time-series photometry reaching about half a magnitude below the Leo IV turnoff, which we detect at V = 24.7 mag, and have performed the first study of the variable star population. We have identified three RR Lyrae stars (all fundamental-mode pulsators, RRab) and one SX Phoenicis variable in the galaxy. In the period-amplitude diagram the Leo IV RR Lyrae stars are located close to the loci of Oosterhoff type I systems and the evolved fundamental-mode RR Lyrae stars in the Galactic globular cluster M3. However, their mean pulsation period, (Pab) = 0.655 days, would suggest an Oosterhoff type II classification for this galaxy. The RR Lyrae stars trace very well the galaxy's horizontal branch, setting its average magnitude at (V RR ) = 21.48 ± 0.03 mag (standard deviation of the mean). This leads to a distance modulus of μ 0 = 20.94 ± 0.07 mag, corresponding to a distance of 154 ± 5 kpc, by adopting for the Leo IV dSph a reddening E(B - V) = 0.04 ± 0.01 mag and a metallicity of [Fe/H] = -2.31 ± 0.10.

  9. Replication of linkage to quantitative trait loci: variation in location and magnitude of the lod score.

    Science.gov (United States)

    Hsueh, W C; Göring, H H; Blangero, J; Mitchell, B D

    2001-01-01

    Replication of linkage signals from independent samples is considered an important step toward verifying the significance of linkage signals in studies of complex traits. The purpose of this empirical investigation was to examine the variability in the precision of localizing a quantitative trait locus (QTL) by analyzing multiple replicates of a simulated data set with the use of variance components-based methods. Specifically, we evaluated across replicates the variation in both the magnitude and the location of the peak lod scores. We analyzed QTLs whose effects accounted for 10-37% of the phenotypic variance in the quantitative traits. Our analyses revealed that the precision of QTL localization was directly related to the magnitude of the QTL effect. For a QTL with effect accounting for > 20% of total phenotypic variation, > 90% of the linkage peaks fall within 10 cM from the true gene location. We found no evidence that, for a given magnitude of the lod score, the presence of interaction influenced the precision of QTL localization.

  10. Alteration of streamflow magnitudes and potential ecological consequences: A multiregional assessment

    Science.gov (United States)

    Carlisle, Daren M.; Wolock, David M.; Meador, Michael R.

    2011-01-01

    Human impacts on watershed hydrology are widespread in the US, but the prevalence and severity of stream-flow alteration and its potential ecological consequences have not been quantified on a national scale. We assessed streamflow alteration at 2888 streamflow monitoring sites throughout the conterminous US. The magnitudes of mean annual (1980–2007) minimum and maximum streamflows were found to have been altered in 86% of assessed streams. The occurrence, type, and severity of streamflow alteration differed markedly between arid and wet climates. Biological assessments conducted on a subset of these streams showed that, relative to eight chemical and physical covariates, diminished flow magnitudes were the primary predictors of biological integrity for fish and macroinvertebrate communities. In addition, the likelihood of biological impairment doubled with increasing severity of diminished streamflows. Among streams with diminished flow magnitudes, increasingly common fish and macroinvertebrate taxa possessed traits characteristic of lake or pond habitats, including a preference for fine-grained substrates and slow-moving currents, as well as the ability to temporarily leave the aquatic environment.

  11. Sinusoidal Parameter Estimation Using Quadratic Interpolation around Power-Scaled Magnitude Spectrum Peaks

    Directory of Open Access Journals (Sweden)

    Kurt James Werner

    2016-10-01

    Full Text Available The magnitude of the Discrete Fourier Transform (DFT of a discrete-time signal has a limited frequency definition. Quadratic interpolation over the three DFT samples surrounding magnitude peaks improves the estimation of parameters (frequency and amplitude of resolved sinusoids beyond that limit. Interpolating on a rescaled magnitude spectrum using a logarithmic scale has been shown to improve those estimates. In this article, we show how to heuristically tune a power scaling parameter to outperform linear and logarithmic scaling at an equivalent computational cost. Although this power scaling factor is computed heuristically rather than analytically, it is shown to depend in a structured way on window parameters. Invariance properties of this family of estimators are studied and the existence of a bias due to noise is shown. Comparing to two state-of-the-art estimators, we show that an optimized power scaling has a lower systematic bias and lower mean-squared-error in noisy conditions for ten out of twelve common windowing functions.

  12. Magnitude and duration of cue-induced craving for marijuana in volunteers with cannabis use disorder

    Science.gov (United States)

    Lundahl, Leslie H.; Greenwald, Mark K.

    2016-01-01

    Aims Evaluate magnitude and duration of subjective and physiologic responses to neutral and marijuana (MJ)–related cues in cannabis dependent volunteers. Methods 33 volunteers (17 male) who met DSM-IV criteria for Cannabis Abuse or Dependence were exposed to neutral (first) then MJ-related visual, auditory, olfactory and tactile cues. Mood, drug craving and physiology were assessed at baseline, post-neutral, post-MJ and 15-min post MJ cue exposure to determine magnitude of cue- responses. For a subset of participants (n=15; 9 male), measures of craving and physiology were collected also at 30-, 90-, and 150-min post-MJ cue to examine duration of cue-effects. Results In cue-response magnitude analyses, visual analog scale (VAS) items craving for, urge to use, and desire to smoke MJ, Total and Compulsivity subscale scores of the Marijuana Craving Questionnaire, anxiety ratings, and diastolic blood pressure (BP) were significantly elevated following MJ vs. neutral cue exposure. In cue-response duration analyses, desire and urge to use MJ remained significantly elevated at 30-, 90- and 150-min post MJ-cue exposure, relative to baseline and neutral cues. Conclusions Presentation of polysensory MJ cues increased MJ craving, anxiety and diastolic BP relative to baseline and neutral cues. MJ craving remained elevated up to 150-min after MJ cue presentation. This finding confirms that carry-over effects from drug cue presentation must be considered in cue reactivity studies. PMID:27436749

  13. Maternal body condition influences magnitude of anti-predator response in offspring.

    Science.gov (United States)

    Bennett, Amanda M; Murray, Dennis L

    2014-11-07

    Organisms exhibit plasticity in response to their environment, but there is large variation even within populations in the expression and magnitude of response. Maternal influence alters offspring survival through size advantages in growth and development. However, the relationship between maternal influence and variation in plasticity in response to predation risk is unknown. We hypothesized that variation in the magnitude of plastic responses between families is at least partly due to maternal provisioning and examined the relationship between maternal condition, egg provisioning and magnitude of plastic response to perceived predation risk (by dragonfly larvae: Aeshna spp.) in northern leopard frogs (Lithobates pipiens). Females in better body condition tended to lay more (clutch size) larger (egg diameter) eggs. Tadpoles responded to predation risk by increasing relative tail depth (morphology) and decreasing activity (behaviour). We found a positive relationship between morphological effect size and maternal condition, but no relationship between behavioural effect size and maternal condition. These novel findings suggest that limitations imposed by maternal condition can constrain phenotypic variation, ultimately influencing the capacity of populations to respond to environmental change. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  14. Locations and magnitudes of historical earthquakes in the Sierra of Ecuador (1587-1996)

    Science.gov (United States)

    Beauval, Céline; Yepes, Hugo; Bakun, William H.; Egred, José; Alvarado, Alexandra; Singaucho, Juan-Carlos

    2010-06-01

    The whole territory of Ecuador is exposed to seismic hazard. Great earthquakes can occur in the subduction zone (e.g. Esmeraldas, 1906, Mw 8.8), whereas lower magnitude but shallower and potentially more destructive earthquakes can occur in the highlands. This study focuses on the historical crustal earthquakes of the Andean Cordillera. Several large cities are located in the Interandean Valley, among them Quito, the capital (~2.5 millions inhabitants). A total population of ~6 millions inhabitants currently live in the highlands, raising the seismic risk. At present, precise instrumental data for the Ecuadorian territory is not available for periods earlier than 1990 (beginning date of the revised instrumental Ecuadorian seismic catalogue); therefore historical data are of utmost importance for assessing seismic hazard. In this study, the Bakun & Wentworth method is applied in order to determine magnitudes, locations, and associated uncertainties for historical earthquakes of the Sierra over the period 1587-1976. An intensity-magnitude equation is derived from the four most reliable instrumental earthquakes (Mw between 5.3 and 7.1). Intensity data available per historical earthquake vary between 10 (Quito, 1587, Intensity >=VI) and 117 (Riobamba, 1797, Intensity >=III). The bootstrap resampling technique is coupled to the B&W method for deriving geographical confidence contours for the intensity centre depending on the data set of each earthquake, as well as confidence intervals for the magnitude. The extension of the area delineating the intensity centre location at the 67 per cent confidence level (+/-1σ) depends on the amount of intensity data, on their internal coherence, on the number of intensity degrees available, and on their spatial distribution. Special attention is dedicated to the few earthquakes described by intensities reaching IX, X and XI degrees. Twenty-five events are studied, and nineteen new epicentral locations are obtained, yielding

  15. Magnitude and Peak Amplitude Relationship for Microseismicity Induced by a Hydraulic Fracture Experiment

    Science.gov (United States)

    Smith, T.; Arce, A. C.; Ji, C.

    2016-12-01

    Waveform cross-correlation technique is widely used to improve the detection of small magnitude events induced by hydraulic fracturing. However, when events are detected, assigning a reliable magnitude is a challenging task, especially considering their small signal amplitude and high background noise during injections. In this study, we adopt the Match & Locate algorithm (M&L, Zhang and Wen, 2015) to analyze seven hours of continuous seismic observations from a hydraulic fracturing experiment in Central California. The site of the stimulated region is only 300-400m away from a 16-receiver vertical-borehole array which spans 230 m. The sampling rate is 4000 Hz. Both the injection sites and borehole array are more than 1.7 km below the surface. This dataset has previously been studied by an industry group, producing a catalog of 1134 events with moment magnitudes (Mw) ranging from -3.1 to -0.9. In this study, we select 202 events from this catalog with high signal to noise ratios to use as templates. Our M&L analysis produces a new catalog that contains 2119 events, which is 10 times more detections than the number of templates and about two times the original catalog. Using these two catalogs, we investigate the relationship of moment magnitude difference (ΔMW) and local magnitude difference (ΔML) between the detected event and corresponding template event. ΔML is computed using the peak amplitude ratio between the detected and template event for each channel. Our analysis yields an empirical relationship of ΔMW=0.64-0.65ΔML with an R2 of 0.99. The coefficient of 2/3 suggests that the information of the event's corner frequency is entirely lost (Hanks and Boore, 1984). The cause might not be unique, which implies that Earth's attenuation at this depth range (>1.7 km) is significant; or the 4000 Hz sampling rate is not sufficient. This relationship is crucial to estimate the b-value of the microseismicity induced by hydraulic fracture experiments. The analysis

  16. Locations and magnitudes of historical earthquakes in the Sierra of Ecuador (1587–1996)

    Science.gov (United States)

    Beauval, Celine; Yepes, Hugo; Bakun, William H.; Egred, Jose; Alvarado, Alexandra; Singaucho, Juan-Carlos

    2010-01-01

    The whole territory of Ecuador is exposed to seismic hazard. Great earthquakes can occur in the subduction zone (e.g. Esmeraldas, 1906, Mw8.8), whereas lower magnitude but shallower and potentially more destructive earthquakes can occur in the highlands. This study focuses on the historical crustal earthquakes of the Andean Cordillera. Several large cities are located in the Interandean Valley, among them Quito, the capital (∼2.5 millions inhabitants). A total population of ∼6 millions inhabitants currently live in the highlands, raising the seismic risk. At present, precise instrumental data for the Ecuadorian territory is not available for periods earlier than 1990 (beginning date of the revised instrumental Ecuadorian seismic catalogue); therefore historical data are of utmost importance for assessing seismic hazard. In this study, the Bakun & Wentworth method is applied in order to determine magnitudes, locations, and associated uncertainties for historical earthquakes of the Sierra over the period 1587–1976. An intensity-magnitude equation is derived from the four most reliable instrumental earthquakes (Mwbetween 5.3 and 7.1). Intensity data available per historical earthquake vary between 10 (Quito, 1587, Intensity ≥VI) and 117 (Riobamba, 1797, Intensity ≥III). The bootstrap resampling technique is coupled to the B&W method for deriving geographical confidence contours for the intensity centre depending on the data set of each earthquake, as well as confidence intervals for the magnitude. The extension of the area delineating the intensity centre location at the 67 per cent confidence level (±1σ) depends on the amount of intensity data, on their internal coherence, on the number of intensity degrees available, and on their spatial distribution. Special attention is dedicated to the few earthquakes described by intensities reaching IX, X and XI degrees. Twenty-five events are studied, and nineteen new epicentral locations are obtained, yielding

  17. Evaluation of the brightness of lightning channels and branches using the magnitude system: Application of astronomical photometry

    Directory of Open Access Journals (Sweden)

    Nobuaki Shimoji

    Full Text Available In this paper, we have evaluated the brightness of lightning leaders shown in a digital still image by applying the astronomical magnitude system. In order to analyze the only lightning leaders, these were extracted from the digital still image. For photometry of the lightning leaders, there is no a standard reference source such as Vega in astronomical photometry. Therefore, assuming the maximum pixel value 255 (in 256 levels as the brightness of a standard reference source, the magnitude of the lightning leaders was obtained. The result showed that the magnitude of the lightning leaders vary spatially (i.e. 2D spatial variability. Furthermore, the result suggested that a low current channel is high magnitude and a high current channel is low magnitude. Keywords: Lightning, Fechner’s law, Magnitude system, Astronomical photometry, Image analysis

  18. The efficacy of support vector machines (SVM) in robust determination of earthquake early warning magnitudes in central Japan

    Science.gov (United States)

    Reddy, Ramakrushna; Nair, Rajesh R.

    2013-10-01

    This work deals with a methodology applied to seismic early warning systems which are designed to provide real-time estimation of the magnitude of an event. We will reappraise the work of Simons et al. (2006), who on the basis of wavelet approach predicted a magnitude error of ±1. We will verify and improve upon the methodology of Simons et al. (2006) by applying an SVM statistical learning machine on the time-scale wavelet decomposition methods. We used the data of 108 events in central Japan with magnitude ranging from 3 to 7.4 recorded at KiK-net network stations, for a source-receiver distance of up to 150 km during the period 1998-2011. We applied a wavelet transform on the seismogram data and calculating scale-dependent threshold wavelet coefficients. These coefficients were then classified into low magnitude and high magnitude events by constructing a maximum margin hyperplane between the two classes, which forms the essence of SVMs. Further, the classified events from both the classes were picked up and linear regressions were plotted to determine the relationship between wavelet coefficient magnitude and earthquake magnitude, which in turn helped us to estimate the earthquake magnitude of an event given its threshold wavelet coefficient. At wavelet scale number 7, we predicted the earthquake magnitude of an event within 2.7 seconds. This means that a magnitude determination is available within 2.7 s after the initial onset of the P-wave. These results shed light on the application of SVM as a way to choose the optimal regression function to estimate the magnitude from a few seconds of an incoming seismogram. This would improve the approaches from Simons et al. (2006) which use an average of the two regression functions to estimate the magnitude.

  19. Magnitude of flood flows for selected annual exceedance probabilities for streams in Massachusetts

    Science.gov (United States)

    Zarriello, Phillip J.

    2017-05-11

    The U.S. Geological Survey, in cooperation with the Massachusetts Department of Transportation, determined the magnitude of flood flows at selected annual exceedance prob­abilities (AEPs) at streamgages in Massachusetts and from these data developed equations for estimating flood flows at ungaged locations in the State. Flood magnitudes were deter­mined for the 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent AEPs at 220 streamgages, 125 of which are in Massachusetts and 95 are in the adjacent States of Connecticut, New Hamp­shire, New York, Rhode Island, and Vermont. AEP flood flows were computed for streamgages using the expected moments algorithm weighted with a recently computed regional skew­ness coefficient for New England.Regional regression equations were developed to estimate the magnitude of floods for selected AEP flows at ungaged sites from 199 selected streamgages and for 60 potential explanatory basin characteristics. AEP flows for 21 of the 125 streamgages in Massachusetts were not used in the final regional regression analysis, primarily because of regulation or redundancy. The final regression equations used general­ized least squares methods to account for streamgage record length and correlation. Drainage area, mean basin elevation, and basin storage explained 86 to 93 percent of the variance in flood magnitude from the 50- to 0.2-percent AEPs, respec­tively. The estimates of AEP flows at streamgages can be improved by using a weighted estimate that is based on the magnitude of the flood and associated uncertainty from the at-site analysis and the regional regression equations. Weighting procedures for estimating AEP flows at an ungaged site on a gaged stream also are provided that improve estimates of flood flows at the ungaged site when hydrologic characteristics do not abruptly change.Urbanization expressed as the percentage of imperviousness provided some explanatory power in the regional regression; however, it was not statistically

  20. Examination of two methods for statistical analysis of data with magnitude and direction emphasizing vestibular research applications

    Science.gov (United States)

    Calkins, D. S.

    1998-01-01

    When the dependent (or response) variable response variable in an experiment has direction and magnitude, one approach that has been used for statistical analysis involves splitting magnitude and direction and applying univariate statistical techniques to the components. However, such treatment of quantities with direction and magnitude is not justifiable mathematically and can lead to incorrect conclusions about relationships among variables and, as a result, to flawed interpretations. This note discusses a problem with that practice and recommends mathematically correct procedures to be used with dependent variables that have direction and magnitude for 1) computation of mean values, 2) statistical contrasts of and confidence intervals for means, and 3) correlation methods.

  1. Fraction magnitude understanding and its unique role in predicting general mathematics achievement at two early stages of fraction instruction.

    Science.gov (United States)

    Liu, Yingyi

    2017-09-08

    Prior studies on fraction magnitude understanding focused mainly on students with relatively sufficient formal instruction on fractions whose fraction magnitude understanding is relatively mature. This study fills a research gap by investigating fraction magnitude understanding in the early stages of fraction instruction. It extends previous findings to children with limited and primary formal fraction instruction. Thirty-five fourth graders with limited fraction instruction and forty fourth graders with primary fraction instruction were recruited from a Chinese primary school. Children's fraction magnitude understanding was assessed with a fraction number line estimation task. Approximate number system (ANS) acuity was assessed with a dot discrimination task. Whole number knowledge was assessed with a whole number line estimation task. General reading and mathematics achievements were collected concurrently and 1 year later. In children with limited fraction instruction, fraction representation was linear and fraction magnitude understanding was concurrently related to both ANS and whole number knowledge. In children with primary fraction instruction, fraction magnitude understanding appeared to (marginally) significantly predict general mathematics achievement 1 year later. Fraction magnitude understanding emerged early during formal instruction of fractions. ANS and whole number knowledge were related to fraction magnitude understanding when children first began to learn about fractions in school. The predictive value of fraction magnitude understanding is likely constrained by its sophistication level. © 2017 The British Psychological Society.

  2. Covariance structure in the skull of Catarrhini: a case of pattern stasis and magnitude evolution.

    Science.gov (United States)

    de Oliveira, Felipe Bandoni; Porto, Arthur; Marroig, Gabriel

    2009-04-01

    The study of the genetic variance/covariance matrix (G-matrix) is a recent and fruitful approach in evolutionary biology, providing a window of investigating for the evolution of complex characters. Although G-matrix studies were originally conducted for microevolutionary timescales, they could be extrapolated to macroevolution as long as the G-matrix remains relatively constant, or proportional, along the period of interest. A promising approach to investigating the constancy of G-matrices is to compare their phenotypic counterparts (P-matrices) in a large group of related species; if significant similarity is found among several taxa, it is very likely that the underlying G-matrices are also equivalent. Here we study the similarity of covariance and correlation structure in a broad sample of Old World monkeys and apes (Catarrhini). We made phylogenetically structured comparisons of correlation and covariance matrices derived from 39 skull traits, ranging from between species to the superfamily level. We also compared the overall magnitude of integration between skull traits (r2) for all Catarrhini genera. Our results show that P-matrices were not strictly constant among catarrhines, but the amount of divergence observed among taxa was generally low. There was significant and positive correlation between the amount of divergence in correlation and covariance patterns among the 30 genera and their phylogenetic distances derived from a recently proposed phylogenetic hypothesis. Our data demonstrate that the P-matrices remained relatively similar along the evolutionary history of catarrhines, and comparisons with the G-matrix available for a New World monkey genus (Saguinus) suggests that the same holds for all anthropoids. The magnitude of integration, in contrast, varied considerably among genera, indicating that evolution of the magnitude, rather than the pattern of inter-trait correlations, might have played an important role in the diversification of the

  3. Multiple Spectral Ratio Analyses Reveal Earthquake Source Spectra of Small Earthquakes and Moment Magnitudes of Microearthquakes

    Science.gov (United States)

    Uchide, T.; Imanishi, K.

    2016-12-01

    Spectral studies for macroscopic earthquake source parameters are helpful for characterizing earthquake rupture process and hence understanding earthquake source physics and fault properties. Those studies require us mute wave propagation path and site effects in spectra of seismograms to accentuate source effect. We have recently developed the multiple spectral ratio method [Uchide and Imanishi, BSSA, 2016] employing many empirical Green's function (EGF) events to reduce errors from the choice of EGF events. This method helps us estimate source spectra more accurately as well as moment ratios among reference and EGF events, which are useful to constrain the seismic moment of microearthquakes. First, we focus on earthquake source spectra. The source spectra have generally been thought to obey the omega-square model with single corner-frequency. However recent studies imply the existence of another corner frequency for some earthquakes. We analyzed small shallow inland earthquakes (3.5 multiple spectral ratio analyses. For 20000 microearthquakes in Fukushima Hamadori and northern Ibaraki prefecture area, we found that the JMA magnitudes (Mj) based on displacement or velocity amplitude are systematically below Mw. The slope of the Mj-Mw relation is 0.5 for Mj 5. We propose a fitting curve for the obtained relationship as Mw = (1/2)Mj + (1/2)(Mjγ + Mcorγ)1/γ+ c, where Mcor is a corner magnitude, γ determines the sharpness of the corner, and c denotes an offset. We obtained Mcor = 4.1, γ = 5.6, and c = -0.47 to fit the observation. The parameters are useful for characterizing the Mj-Mw relationship. This non-linear relationship affects the b-value of the Gutenberg-Richter law. Quantitative discussions on b-values are affected by the definition of magnitude to use.

  4. Influence of climate change on flood magnitude and seasonality in the Arga River catchment in Spain

    Science.gov (United States)

    Garijo, Carlos; Mediero, Luis

    2018-04-01

    Climate change projections suggest that extremes, such as floods, will modify their behaviour in the future. Detailed catchment-scale studies are needed to implement the European Union Floods Directive and give recommendations for flood management and design of hydraulic infrastructure. In this study, a methodology to quantify changes in future flood magnitude and seasonality due to climate change at a catchment scale is proposed. Projections of 24 global climate models are used, with 10 being downscaled by the Spanish Meteorological Agency (Agencia Estatal de Meteorología, AEMET) and 14 from the EURO-CORDEX project, under two representative concentration pathways (RCPs) 4.5 and 8.5, from the Fifth Assessment Report provided by the Intergovernmental Panel on Climate Change. Downscaled climate models provided by the AEMET were corrected in terms of bias. The HBV rainfall-runoff model was selected to simulate the catchment hydrological behaviour. Simulations were analysed through both annual maximum and peaks-over-threshold (POT) series. The results show a decrease in the magnitude of extreme floods for the climate model projections downscaled by the AEMET. However, results for the climate model projections downscaled by EURO-CORDEX show differing trends, depending on the RCP. A small decrease in the flood magnitude was noticed for the RCP 4.5, while an increase was found for the RCP 8.5. Regarding the monthly seasonality analysis performed by using the POT series, a delay in the flood timing from late-autumn to late-winter is identified supporting the findings of recent studies performed with observed data in recent decades.

  5. Empirical photometric calibration of the Gaia red clump: Colours, effective temperature, and absolute magnitude

    Science.gov (United States)

    Ruiz-Dern, L.; Babusiaux, C.; Arenou, F.; Turon, C.; Lallement, R.

    2018-01-01

    Context. Gaia Data Release 1 allows the recalibration of standard candles such as the red clump stars. To use those stars, they first need to be accurately characterised. In particular, colours are needed to derive interstellar extinction. As no filter is available for the first Gaia data release and to avoid the atmosphere model mismatch, an empirical calibration is unavoidable. Aims: The purpose of this work is to provide the first complete and robust photometric empirical calibration of the Gaia red clump stars of the solar neighbourhood through colour-colour, effective temperature-colour, and absolute magnitude-colour relations from the Gaia, Johnson, 2MASS, HIPPARCOS, Tycho-2, APASS-SLOAN, and WISE photometric systems, and the APOGEE DR13 spectroscopic temperatures. Methods: We used a 3D extinction map to select low reddening red giants. To calibrate the colour-colour and the effective temperature-colour relations, we developed a MCMC method that accounts for all variable uncertainties and selects the best model for each photometric relation. We estimated the red clump absolute magnitude through the mode of a kernel-based distribution function. Results: We provide 20 colour versus G-Ks relations and the first Teff versus G-Ks calibration. We obtained the red clump absolute magnitudes for 15 photometric bands with, in particular, MKs = (-1.606 ± 0.009) and MG = (0.495 ± 0.009) + (1.121 ± 0.128)(G-Ks-2.1). We present a dereddened Gaia-TGAS HR diagram and use the calibrations to compare its red clump and its red giant branch bump with Padova isochrones. Full Table A.1 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/609/A116

  6. Decisions under risk in Parkinson's disease: preserved evaluation of probability and magnitude.

    Science.gov (United States)

    Sharp, Madeleine E; Viswanathan, Jayalakshmi; McKeown, Martin J; Appel-Cresswell, Silke; Stoessl, A Jon; Barton, Jason J S

    2013-11-01

    Unmedicated Parkinson's disease patients tend to be risk-averse while dopaminergic treatment causes a tendency to take risks. While dopamine agonists may result in clinically apparent impulse control disorders, treatment with levodopa also causes shift in behaviour associated with an enhanced response to rewards. Two important determinants in decision-making are how subjects perceive the magnitude and probability of outcomes. Our objective was to determine if patients with Parkinson's disease on or off levodopa showed differences in their perception of value when making decisions under risk. The Vancouver Gambling task presents subjects with a choice between one prospect with larger outcome and a second with higher probability. Eighteen age-matched controls and eighteen patients with Parkinson's disease before and after levodopa were tested. In the Gain Phase subjects chose between one prospect with higher probability and another with larger reward to maximize their gains. In the Loss Phase, subjects played to minimize their losses. Patients with Parkinson's disease, on or off levodopa, were similar to controls when evaluating gains. However, in the Loss Phase before levodopa, they were more likely to avoid the prospect with lower probability but larger loss, as indicated by the steeper slope of their group psychometric function (t(24) = 2.21, p = 0.04). Modelling with prospect theory suggested that this was attributable to a 28% overestimation of the magnitude of loss, rather than an altered perception of its probability. While pre-medicated patients with Parkinson's disease show risk-aversion for large losses, patients on levodopa have normal perception of magnitude and probability for both loss and gain. The finding of accurate and normally biased decisions under risk in medicated patients with PD is important because it indicates that, if there is indeed anomalous risk-seeking behaviour in such a cohort, it may derive from abnormalities in components of

  7. Perceived state of self during motion can differentially modulate numerical magnitude allocation.

    Science.gov (United States)

    Arshad, Q; Nigmatullina, Y; Roberts, R E; Goga, U; Pikovsky, M; Khan, S; Lobo, R; Flury, A-S; Pettorossi, V E; Cohen-Kadosh, R; Malhotra, P A; Bronstein, A M

    2016-09-01

    Although a direct relationship between numerical allocation and spatial attention has been proposed, recent research suggests that these processes are not directly coupled. In keeping with this, spatial attention shifts induced either via visual or vestibular motion can modulate numerical allocation in some circumstances but not in others. In addition to shifting spatial attention, visual or vestibular motion paradigms also (i) elicit compensatory eye movements which themselves can influence numerical processing and (ii) alter the perceptual state of 'self', inducing changes in bodily self-consciousness impacting upon cognitive mechanisms. Thus, the precise mechanism by which motion modulates numerical allocation remains unknown. We sought to investigate the influence that different perceptual experiences of motion have upon numerical magnitude allocation while controlling for both eye movements and task-related effects. We first used optokinetic visual motion stimulation (OKS) to elicit the perceptual experience of either 'visual world' or 'self'-motion during which eye movements were identical. In a second experiment, we used a vestibular protocol examining the effects of perceived and subliminal angular rotations in darkness, which also provoked identical eye movements. We observed that during the perceptual experience of 'visual world' motion, rightward OKS-biased judgments towards smaller numbers, whereas leftward OKS-biased judgments towards larger numbers. During the perceptual experience of 'self-motion', judgments were biased towards larger numbers irrespective of the OKS direction. Contrastingly, vestibular motion perception was found not to modulate numerical magnitude allocation, nor was there any differential modulation when comparing 'perceived' vs. 'subliminal' rotations. We provide a novel demonstration that numerical magnitude allocation can be differentially modulated by the perceptual state of self during visual but not vestibular mediated motion

  8. Reinternação pediátrica: conhecendo a magnitude do problema

    Directory of Open Access Journals (Sweden)

    Lélia Maria Madeira

    1996-12-01

    Full Text Available As internações sucessivas de crianças têm sido objeto de estudo de autores, tanto nacionais como internacionais. Embora quase todos reconheçam a interrelação entre este fenômeno com as condições de vida da criança e a qualidade da assistência oferecida pelos serviços de saúde, a falta de critérios mais precisos fazem com que, de fato, não se conheça a magnitude do problema e, principalmente, as razões para a ocorrência tão freqüente em nosso meio. Esta pesquisa exploratória- descritiva, parte de um projeto mais amplo e buscou conhecer a magnitude do problema das reinternações, através da caracterização das crianças reinternadas em uma instituição hospitalar. Foi realizada no Centro Geral de Pediatria (CGP. de Belo Horizonte, Minas Gerais, no período de janeiro a dezembro de 1993. Os dados foram coletados, principalmente nos prontuários e registros de internações. Entre os resultados as reinternações infantís extrapolam os dados oficiais do próprio hospital; há predomínio de estados mórbidos evitáveis como desencadeadores das reinternações; a maioria das crianças provém de zonas periféricas do Município, onde se concentra a população de baixa renda e de condições precárias de vida, entretanto os critérios adotados pela instituição são insuficientes para refletir a magnitude deste problema.

  9. Developmental dyscalculia: compensatory mechanisms in left intraparietal regions in response to nonsymbolic magnitudes

    Directory of Open Access Journals (Sweden)

    Starke Marc

    2009-08-01

    Full Text Available Abstract Background Functional magnetic resonance imaging (fMRI studies investigating the neural mechanisms underlying developmental dyscalculia are scarce and results are thus far inconclusive. Main aim of the present study is to investigate the neural correlates of nonsymbolic number magnitude processing in children with and without dyscalculia. Methods 18 children (9 with dyscalculia were asked to solve a non-symbolic number magnitude comparison task (finger patterns during brain scanning. For the spatial control task identical stimuli were employed, instructions varying only (judgment of palm rotation. This design enabled us to present identical stimuli with identical visual processing requirements in the experimental and the control task. Moreover, because numerical and spatial processing relies on parietal brain regions, task-specific contrasts are expected to reveal true number-specific activations. Results Behavioral results during scanning reveal that despite comparable (almost at ceiling performance levels, task-specific activations were stronger in dyscalculic children in inferior parietal cortices bilaterally (intraparietal sulcus, supramarginal gyrus, extending to left angular gyrus. Interestingly, fMRI signal strengths reflected a group × task interaction: relative to baseline, controls produced significant deactivations in (intraparietal regions bilaterally in response to number but not spatial processing, while the opposite pattern emerged in dyscalculics. Moreover, beta weights in response to number processing differed significantly between groups in left – but not right – (intraparietal regions (becoming even positive in dyscalculic children. Conclusion Overall, findings are suggestive of (a less consistent neural activity in right (intraparietal regions upon processing nonsymbolic number magnitudes; and (b compensatory neural activity in left (intraparietal regions in developmental dyscalculia.

  10. Developmental dyscalculia: compensatory mechanisms in left intraparietal regions in response to nonsymbolic magnitudes.

    Science.gov (United States)

    Kaufmann, Liane; Vogel, Stephan E; Starke, Marc; Kremser, Christian; Schocke, Michael; Wood, Guilherme

    2009-08-05

    Functional magnetic resonance imaging (fMRI) studies investigating the neural mechanisms underlying developmental dyscalculia are scarce and results are thus far inconclusive. Main aim of the present study is to investigate the neural correlates of nonsymbolic number magnitude processing in children with and without dyscalculia. 18 children (9 with dyscalculia) were asked to solve a non-symbolic number magnitude comparison task (finger patterns) during brain scanning. For the spatial control task identical stimuli were employed, instructions varying only (judgment of palm rotation). This design enabled us to present identical stimuli with identical visual processing requirements in the experimental and the control task. Moreover, because numerical and spatial processing relies on parietal brain regions, task-specific contrasts are expected to reveal true number-specific activations. Behavioral results during scanning reveal that despite comparable (almost at ceiling) performance levels, task-specific activations were stronger in dyscalculic children in inferior parietal cortices bilaterally (intraparietal sulcus, supramarginal gyrus, extending to left angular gyrus). Interestingly, fMRI signal strengths reflected a group x task interaction: relative to baseline, controls produced significant deactivations in (intra)parietal regions bilaterally in response to number but not spatial processing, while the opposite pattern emerged in dyscalculics. Moreover, beta weights in response to number processing differed significantly between groups in left - but not right - (intra)parietal regions (becoming even positive in dyscalculic children). Overall, findings are suggestive of (a) less consistent neural activity in right (intra)parietal regions upon processing nonsymbolic number magnitudes; and (b) compensatory neural activity in left (intra)parietal regions in developmental dyscalculia.

  11. Magnitude of 14C/12C variations based on archaeological samples

    International Nuclear Information System (INIS)

    Kusumgar, S.; Agrawal, D.P.

    1977-01-01

    The magnitude of 14 C/ 12 C variations in the period A.D. 5O0 to 200 B.C. and 370 B.C. to 2900 B.C. is discussed. The 14 C dates of well-dated archaeological samples from India and Egypt do not show any significant divergence from the historical ages. On the other hand, the corrections based on dendrochronological samples show marked deviations for the same time period. A plea is, therefore, made to study old tree samples from Anatolia and Irish bogs and archaeological samples from west Asia to arrive at a more realistic calibration curve. (author)

  12. Effect of the total charge on the magnitudes of the topological cross sections in hadron interactions

    International Nuclear Information System (INIS)

    Nikitaev, D.N.; Smirnova, L.N.

    1985-01-01

    The reconstructed distributions in the total particle multiplicity in pp interactions are used to obtain the magnitudes of the topological cross sections in pp-bar interactions with baryons in the final state. The mean particle multiplicities are found for the differences of the topological cross sections (K - p-K + p) and (π - p-π + p) taking into account the difference in the total charge of these reactions. The mean numbers of neutral particles are given for events with different numbers of charged particles in pp interactions

  13. Longitudinal decorrelation measures of flow magnitude and event-plane angles in ultrarelativistic nuclear collisions

    Science.gov (United States)

    BoŻek, Piotr; Broniowski, Wojciech

    2018-03-01

    We discuss the forward-backward correlations of harmonic flow in Pb +Pb collisions at the CERN Large Hadron Collider, applying standard multibin measures as well as new measures proposed here. We illustrate the methods with hydrodynamic model simulations based on event-by-event initial conditions from the wounded quark model with asymmetric rapidity emission profiles. Within the model, we examine independently the event-plane angle and the flow magnitude decorrelations. We find a specific hierarchy between various flow decorrelation measures and confirm certain factorization relations. We find qualitative agreement of the model and the data from the ATLAS and CMS Collaborations.

  14. Stress and subsidy effects of seagrass wrack duration, frequency, and magnitude on salt marsh community structure.

    Science.gov (United States)

    Hanley, Torrance C; Kimbro, David L; Hughes, Anne Randall

    2017-07-01

    Environmental perturbations can strongly affect community processes and ecosystem functions by acting primarily as a subsidy that increases productivity, a stress that decreases productivity, or both, with the predominant effect potentially shifting from subsidy to stress as the overall intensity of the perturbation increases. While perturbations are often considered along a single axis of intensity, they consist of multiple components (e.g., magnitude, frequency, and duration) that may not have equivalent stress and/or subsidy effects. Thus, different combinations of perturbation components may elicit community and ecosystem responses that differ in strength and/or direction (i.e., stress or subsidy) even if they reflect a similar overall perturbation intensity. To assess the independent and interactive effects of perturbation components, we experimentally manipulated the magnitude, frequency, and duration of wrack deposition, a common stress-subsidy in a variety of coastal systems. The effects of wrack perturbation on salt marsh community and ecosystem properties were assessed both in the short-term (at the end of a 12-week experimental manipulation) and long-term (6 months after the end of the experiment). In the short-term, plants and associated benthic invertebrates exhibited primarily stress-based responses to wrack perturbation. The extent of these stress effects on density of the dominant plant Spartina alterniflora, total plant percent cover, invertebrate abundance, and sediment oxygen availability were largely determined by perturbation duration. Yet, higher nitrogen content of Spartina, which indicates a subsidy effect of wrack, was influenced primarily by perturbation magnitude in the short-term. In the longer term, perturbation magnitude determined the extent of both stress and subsidy effects of wrack perturbation, with lower subordinate plant percent cover and snail density, and higher Spartina nitrogen content in high wrack biomass treatments

  15. All-optical bit magnitude comparator device using metal-insulator-metal plasmonic waveguide

    Science.gov (United States)

    Kumar, Santosh; Singh, Lokendra; Chen, Nan-Kuang

    2017-12-01

    A plasmonic metal-insulator-metal (MIM) waveguide has great success in confining the surface plasmon up to a deep subwavelength scale. The structure of a nonlinear Mach-Zehnder interferometer (MZI) using a plasmonic MIM waveguide has been analyzed. A one-bit magnitude comparator has been designed using an MZI and two linear control waveguides. The device works on the Kerr effect inside the plasmonics waveguide. The mathematical description of the device is explained. The simulation of the device is done using MATLAB® and the finite-difference time-domain (FDTD) method.

  16. Study of the global and regional climatic impacts of ENSO magnitude using SPEEDY AGCM

    KAUST Repository

    Dogar, Muhammad Mubashar; Kucharski, Fred; Azharuddin, Syed

    2017-01-01

    ENSO is considered as a strong atmospheric teleconnection that has pronounced global and regional circulation effects. It modifies global monsoon system, especially, Asian and African monsoons. Previous studies suggest that both the frequency and magnitude of ENSO events have increased over the last few decades resulting in a need to study climatic impacts of ENSO magnitude both at global and regional scales. Hence, to better understand the impact of ENSO amplitude over the tropical and extratropical regions focussing on the Asian and African domains, ENSO sensitivity experiments are conducted using ICTPAGCM (‘SPEEDY’). It is anticipated that the tropical Pacific SST forcing will be enough to produce ENSO-induced teleconnection patterns; therefore, the model is forced using NINO3.4 regressed SST anomalies over the tropical Pacific only. SPEEDY reproduces the impact of ENSO over the Pacific, North and South America and African regions very well. However, it underestimates ENSO teleconnection patterns and associated changes over South Asia, particularly in the Indian region, which suggests that the tropical Pacific SST forcing is not sufficient to represent ENSO-induced teleconnection patterns over South Asia. Therefore, SST forcing over the tropical Indian Ocean together with air–sea coupling is also required for better representation of ENSO-induced changes in these regions. Moreover, results obtained by this pacemaker experiment show that ENSO impacts are relatively stronger over the Inter-Tropical Convergence Zone (ITCZ) compared to extratropics and high latitude regions. The positive phase of ENSO causes weakening in rainfall activity over African tropical rain belt, parts of South and Southeast Asia, whereas, the La Niña phase produces more rain over these regions during the summer season. Model results further reveal that ENSO magnitude has a stronger impact over African Sahel and South Asia, especially over the Indian region because of its significant

  17. On the magnitude of the CO/sub 2/ greenhouse effect

    Energy Technology Data Exchange (ETDEWEB)

    Idso, S B

    1983-01-01

    Empirical evidence indicates that the magnitude of global warming to be expected from the relase of CO/sub 2/ into the atmosphere by the burning of fossil fuels has been greatly overestimated by scientists employing general circulation models of the atmosphere. Indeed, real-world data suggest that increasing levels of atmospheric CO/sub 2/ are actually to be desired, as they have no significant climatic ramifications but tend to promote greater water use efficiency and productivity in the world's natural and managed forests, crops and rangelands.

  18. On the magnitude of the CO/sub 2/ greenhouse effect

    Energy Technology Data Exchange (ETDEWEB)

    Idso, S B

    1983-01-01

    Empirical evidence indicates that the magnitude of global warming to be expected from the release of CO/sub 2/ into the atmosphere by the burning of fossil fuels has been greatly overestimated by scientists employing general circulation models of the atmosphere. Indeed, real-world data suggest that increasing levels of atmospheric CO/sub 2/ are actually to be desired, as they have no significant climatic ramifications but tend to promote greater water use efficiency and productivity in the world's natural and managed forests, crops and rangelands. (30 refs.)

  19. Voltage magnitude and margin controller for remote industrial microgrid with high wind penetration

    DEFF Research Database (Denmark)

    Cai, Yu; Lin, Jin; Song, Yonghua

    2013-01-01

    It is well known that the remote industrial microgrid is located at the periphery of the grid, which is weakly connected to the main grid. In order to enhance the voltage stability and ensure a good power quality for industries, a voltage magnitude and margin controller based on wind turbines...... is proposed in this paper. This controller includes two parts to improve voltage stability in different time scales by using local measurements. Case studies conducted for a remote microgrid with high wind penetration have proved the effectiveness of the proposed control scheme....

  20. Repose time and cumulative moment magnitude: A new tool for forecasting eruptions?

    Science.gov (United States)

    Thelen, W. A.; Malone, S. D.; West, M. E.

    2010-09-01

    During earthquake swarms on active volcanoes, one of the primary challenges facing scientists is determining the likelihood of an eruption. Here we present the relation between repose time and the cumulative moment magnitude (CMM) as a tool to aid in differentiating between an eruption and a period of unrest. In several case studies, the CMM is lower at shorter repose times than it is at longer repose times. The relationship between repose time and CMM may be linear in log-log space, particularly at Mount St. Helens. We suggest that the volume and competence of the plug within the conduit drives the strength of the precursory CMM.

  1. A comparison of moment magnitude estimates for the European-Mediterranean and Italian regions

    Science.gov (United States)

    Gasperini, Paolo; Lolli, Barbara; Vannucci, Gianfranco; Boschi, Enzo

    2012-09-01

    With the goal of constructing a homogeneous data set of moment magnitudes (Mw) to be used for seismic hazard assessment, we compared Mw estimates from moment tensor catalogues available online. We found an apparent scaling disagreement between Mw estimates from the National Earthquake Information Center (NEIC) of the US Geological Survey and from the Global Centroid Moment Tensor (GCMT) project. We suspect that this is the effect of an underestimation of Mw > 7.0 (M0 > 4.0 × 1019 Nm) computed by NEIC owing to the limitations of their computational approach. We also found an apparent scaling disagreement between GCMT and two regional moment tensor catalogues provided by the 'Eidgenössische Technische Hochschule Zürich' (ETHZ) and by the European-Mediterranean Regional Centroid Moment Tensor (RCMT) project of the Italian 'Istituto Nazionale di Geofisica e Vulcanologia' (INGV). This is probably the effect of the overestimation of Mw < 5.5 (M0 < 2.2 × 1017 Nm), up to year 2002, and of Mw < 5.0 (M0 < 4.0 × 1016 Nm), since year 2003, owing to the physical limitations of the standard CMT inversion method used by GCMT for the earthquakes of relatively low magnitude. If the discrepant data are excluded from the comparisons, the scaling disagreements become insignificant in all cases. We observed instead small absolute offsets (≤0.1 units) for NEIC and ETHZ catalogues with respect to GCMT whereas there is an almost perfect correspondence between RCMT and GCMT. Finally, we found a clear underestimation of about 0.2 units of Mw magnitudes computed at the INGV using the time-domain moment tensor (TDMT) method with respect to those reported by GCMT and RCMT. According to our results, we suggest appropriate offset corrections to be applied to Mw estimates from NEIC, ETHZ and TDMT catalogues before merging their data with GCMT and RCMT catalogues. We suggest as well to discard the probably discrepant data from NEIC and GCMT if other Mw estimates from different sources are

  2. Study of the global and regional climatic impacts of ENSO magnitude using SPEEDY AGCM

    KAUST Repository

    Dogar, Muhammad Mubashar

    2017-03-09

    ENSO is considered as a strong atmospheric teleconnection that has pronounced global and regional circulation effects. It modifies global monsoon system, especially, Asian and African monsoons. Previous studies suggest that both the frequency and magnitude of ENSO events have increased over the last few decades resulting in a need to study climatic impacts of ENSO magnitude both at global and regional scales. Hence, to better understand the impact of ENSO amplitude over the tropical and extratropical regions focussing on the Asian and African domains, ENSO sensitivity experiments are conducted using ICTPAGCM (‘SPEEDY’). It is anticipated that the tropical Pacific SST forcing will be enough to produce ENSO-induced teleconnection patterns; therefore, the model is forced using NINO3.4 regressed SST anomalies over the tropical Pacific only. SPEEDY reproduces the impact of ENSO over the Pacific, North and South America and African regions very well. However, it underestimates ENSO teleconnection patterns and associated changes over South Asia, particularly in the Indian region, which suggests that the tropical Pacific SST forcing is not sufficient to represent ENSO-induced teleconnection patterns over South Asia. Therefore, SST forcing over the tropical Indian Ocean together with air–sea coupling is also required for better representation of ENSO-induced changes in these regions. Moreover, results obtained by this pacemaker experiment show that ENSO impacts are relatively stronger over the Inter-Tropical Convergence Zone (ITCZ) compared to extratropics and high latitude regions. The positive phase of ENSO causes weakening in rainfall activity over African tropical rain belt, parts of South and Southeast Asia, whereas, the La Niña phase produces more rain over these regions during the summer season. Model results further reveal that ENSO magnitude has a stronger impact over African Sahel and South Asia, especially over the Indian region because of its significant

  3. Combining spanwise morphing, inline motion and model based optimization for force magnitude and direction control

    Science.gov (United States)

    Scheller, Johannes; Braza, Marianna; Triantafyllou, Michael

    2016-11-01

    Bats and other animals rapidly change their wingspan in order to control the aerodynamic forces. A NACA0013 type airfoil with dynamically changing span is proposed as a simple model to experimentally study these biomimetic morphing wings. Combining this large-scale morphing with inline motion allows to control both force magnitude and direction. Force measurements are conducted in order to analyze the impact of the 4 degree of freedom flapping motion on the flow. A blade-element theory augmented unsteady aerodynamic model is then used to derive optimal flapping trajectories.

  4. Curve Magnitude in Patients Referred for Evaluation of Adolescent Idiopathic Scoliosis

    DEFF Research Database (Denmark)

    Ohrt-Nissen, Søren; Hallager, Dennis Winge; Henriksen, Jeppe L.

    2016-01-01

    Study design Retrospective cross-sectional study. Objectives To analyze the referral pattern of patients with adolescent idiopathic scoliosis (AIS) in a tertiary hospital in a nationalized health care system without school screening and to compare curve magnitude on referral with results reported...... scoliosis screening. Our tertiary institution receives referrals for evaluation of AIS from general practitioners (GPs) and other hospitals or private specialists. Method A review was conducted on all patients diagnosed with AIS between 2010 and 2015. Data collection included age, gender, menarchal status...

  5. Fundamental aspects of seismic event detection, magnitude estimation and their interrelation

    International Nuclear Information System (INIS)

    Ringdal, F.

    1977-01-01

    The main common subject of the papers forming this thesis is statistical model development within the seismological disciplines of seismic event detection and event magnitude estimation. As more high quality seismic data become available as a result of recent seismic network developments, the opportunity will exist for large scale application and further refinement of these models. It is hoped that the work presented here will facilitate improved understanding of the basic issues, both within earthquake-explosion discrimination, in the framework of which most of this work originated, and in seismology in general. (Auth.)

  6. Magnitude and processes of bank erosion at a small stream in Denmark

    DEFF Research Database (Denmark)

    Veihe, Anita; Jensen, Niels H.; Schiøtz, Iris Gunia

    2011-01-01

    River banks are important sources of sediment and phosphorus to fluvial systems, and the erosion processes operating on the banks are complex and change over time. This study explores the magnitude of bank erosion on a cohesive streambank within a small channelized stream and studies the various...... (17Ð6–30Ð1 mm year-1) and total P content on the banks were relatively high, which makes the bank an important source of sediment and phosphorus to the stream, and it was estimated that 0Ð27 kg Ptot year-1 ha-1 may potentially be supplied to the stream from the banks. Yearly pin erosion rates...

  7. Sum of the Magnitude for Hard Decision Decoding Algorithm Based on Loop Update Detection

    Science.gov (United States)

    Meng, Jiahui; Zhao, Danfeng; Tian, Hai; Zhang, Liang

    2018-01-01

    In order to improve the performance of non-binary low-density parity check codes (LDPC) hard decision decoding algorithm and to reduce the complexity of decoding, a sum of the magnitude for hard decision decoding algorithm based on loop update detection is proposed. This will also ensure the reliability, stability and high transmission rate of 5G mobile communication. The algorithm is based on the hard decision decoding algorithm (HDA) and uses the soft information from the channel to calculate the reliability, while the sum of the variable nodes’ (VN) magnitude is excluded for computing the reliability of the parity checks. At the same time, the reliability information of the variable node is considered and the loop update detection algorithm is introduced. The bit corresponding to the error code word is flipped multiple times, before this is searched in the order of most likely error probability to finally find the correct code word. Simulation results show that the performance of one of the improved schemes is better than the weighted symbol flipping (WSF) algorithm under different hexadecimal numbers by about 2.2 dB and 2.35 dB at the bit error rate (BER) of 10−5 over an additive white Gaussian noise (AWGN) channel, respectively. Furthermore, the average number of decoding iterations is significantly reduced. PMID:29342963

  8. Hypotensive Response Magnitude and Duration in Hypertensives: Continuous and Interval Exercise

    Directory of Open Access Journals (Sweden)

    Raphael Santos Teodoro de Carvalho

    2015-03-01

    Full Text Available Background: Although exercise training is known to promote post-exercise hypotension, there is currently no consistent argument about the effects of manipulating its various components (intensity, duration, rest periods, types of exercise, training methods on the magnitude and duration of hypotensive response. Objective: To compare the effect of continuous and interval exercises on hypotensive response magnitude and duration in hypertensive patients by using ambulatory blood pressure monitoring (ABPM. Methods: The sample consisted of 20 elderly hypertensives. Each participant underwent three ABPM sessions: one control ABPM, without exercise; one ABPM after continuous exercise; and one ABPM after interval exercise. Systolic blood pressure (SBP, diastolic blood pressure (DBP, mean arterial pressure (MAP, heart rate (HR and double product (DP were monitored to check post-exercise hypotension and for comparison between each ABPM. Results: ABPM after continuous exercise and after interval exercise showed post-exercise hypotension and a significant reduction (p < 0.05 in SBP, DBP, MAP and DP for 20 hours as compared with control ABPM. Comparing ABPM after continuous and ABPM after interval exercise, a significant reduction (p < 0.05 in SBP, DBP, MAP and DP was observed in the latter. Conclusion: Continuous and interval exercise trainings promote post-exercise hypotension with reduction in SBP, DBP, MAP and DP in the 20 hours following exercise. Interval exercise training causes greater post-exercise hypotension and lower cardiovascular overload as compared with continuous exercise.

  9. Hypotensive response magnitude and duration in hypertensives: continuous and interval exercise.

    Science.gov (United States)

    Carvalho, Raphael Santos Teodoro de; Pires, Cássio Mascarenhas Robert; Junqueira, Gustavo Cardoso; Freitas, Dayana; Marchi-Alves, Leila Maria

    2015-03-01

    Although exercise training is known to promote post-exercise hypotension, there is currently no consistent argument about the effects of manipulating its various components (intensity, duration, rest periods, types of exercise, training methods) on the magnitude and duration of hypotensive response. To compare the effect of continuous and interval exercises on hypotensive response magnitude and duration in hypertensive patients by using ambulatory blood pressure monitoring (ABPM). The sample consisted of 20 elderly hypertensives. Each participant underwent three ABPM sessions: one control ABPM, without exercise; one ABPM after continuous exercise; and one ABPM after interval exercise. Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR) and double product (DP) were monitored to check post-exercise hypotension and for comparison between each ABPM. ABPM after continuous exercise and after interval exercise showed post-exercise hypotension and a significant reduction (p ABPM. Comparing ABPM after continuous and ABPM after interval exercise, a significant reduction (p < 0.05) in SBP, DBP, MAP and DP was observed in the latter. Continuous and interval exercise trainings promote post-exercise hypotension with reduction in SBP, DBP, MAP and DP in the 20 hours following exercise. Interval exercise training causes greater post-exercise hypotension and lower cardiovascular overload as compared with continuous exercise.

  10. Development of structural vulnerability curve associated with high magnitude torrent occurrences in Switzerland

    Science.gov (United States)

    Wing-Yuen Chow, Candace; Bründl, Michael; Keiler, Margreth

    2017-04-01

    In mountain regions, high economic losses have increased significantly in the past decades due to severe hazard processes, in spite of notable investments in hazard management. Assessing the vulnerability of built structures to high magnitude torrent events is a part of consequence analysis, where hazard intensity is related to the degree of loss sustained. While vulnerability curves have been developed for different countries, the presented work contributes new data from Swiss-based case studies that address a known gap associated with the consequences of high magnitude events. Data for this stage of the investigation communicates the degree of loss associated with affected structures and has been provided by local authorities dealing with natural hazards (e.g. Amt für Wald des Kantons Bern (KAWA) and cantonal insurance providers). Information used for the empirical quantification of vulnerability to torrent processes is derived from detailed post-event documentation and the loss database and verified with field visits. Building the initial database supports data sharing and the systematic inclusion of additional case studies as they become available. The collection of this new data is fundamental to the development of a local vulnerability curve based on observed sediment deposition heights, a proxy for describing hazard intensity. The result will then be compared to curves derived from Austrian and Italian datasets.

  11. Interaction of Volcanic Forcing and El Nino: Sensitivity to the Eruption Magnitude and El Nino Intensity

    KAUST Repository

    Predybaylo, Evgeniya

    2015-04-01

    Volcanic aerosols formed in the stratosphere after strong explosive eruptions influence Earth\\'s radiative balance, affecting atmospheric and oceanic temperatures and circulation. It was observed that the recent volcanic eruptions frequently occurred in El Nino years. Analysis of the paleo data confirms that the probability of a sequent El Nino occurrence after the eruption increases. To better understand the physical mechanism of this interaction we employed ocean-atmosphere coupled climate model CM2.1, developed in the Geophysical Fluid Dynamics Laboratory, and conducted a series of numerical experiments using initial conditions with different El Nino Southern Oscillation (ENSO) strengths forced by volcanic eruptions of different magnitudes, Pinatubo of June 1991 and Tambora of April 1815: (i) strong ENSO/Pinatubo, (ii) weak ENSO/Pinatubo, (iii) strong ENSO/Tambora. The amount of ejected material from the Tambora eruption was about three times greater than that of the Pinatubo eruption. The initial conditions with El Nino were sampled from the CM2.1 long control run. Our simulations show the enhancement of El Nino in the second year after an eruption. We found that the spatial-temporal structure of model responses is sensitive to both the magnitude of an eruption and the strength of El Nino. We analyzed the ocean dynamic in the tropical Pacific for all cases to uncover the physical mechanism, resulting in the enhanced and/or prolonged El Nino.

  12. The differential effects of increasing frequency and magnitude of extreme events on coral populations.

    Science.gov (United States)

    Fabina, Nicholas S; Baskett, Marissa L; Gross, Kevin

    2015-09-01

    Extreme events, which have profound ecological consequences, are changing in both frequency and magnitude with climate change. Because extreme temperatures induce coral bleaching, we can explore the relative impacts of changes in frequency and magnitude of high temperature events on coral reefs. Here, we combined climate projections and a dynamic population model to determine how changing bleaching regimes influence coral persistence. We additionally explored how coral traits and competition with macroalgae mediate changes in bleaching regimes. Our results predict that severe bleaching events reduce coral persistence more than frequent bleaching. Corals with low adult mortality and high growth rates are successful when bleaching is mild, but bleaching resistance is necessary to persist when bleaching is severe, regardless of frequency. The existence of macroalgae-dominated stable states reduces coral persistence and changes the relative importance of coral traits. Building on previous studies, our results predict that management efforts may need to prioritize protection of "weaker" corals with high adult mortality when bleaching is mild, and protection of "stronger" corals with high bleaching resistance when bleaching is severe. In summary, future reef projections and conservation targets depend on both local bleaching regimes and biodiversity.

  13. Estimates of the magnitudes of major marine mass extinctions in earth history

    Science.gov (United States)

    Stanley, Steven M.

    2016-10-01

    Procedures introduced here make it possible, first, to show that background (piecemeal) extinction is recorded throughout geologic stages and substages (not all extinction has occurred suddenly at the ends of such intervals); second, to separate out background extinction from mass extinction for a major crisis in earth history; and third, to correct for clustering of extinctions when using the rarefaction method to estimate the percentage of species lost in a mass extinction. Also presented here is a method for estimating the magnitude of the Signor-Lipps effect, which is the incorrect assignment of extinctions that occurred during a crisis to an interval preceding the crisis because of the incompleteness of the fossil record. Estimates for the magnitudes of mass extinctions presented here are in most cases lower than those previously published. They indicate that only ˜81% of marine species died out in the great terminal Permian crisis, whereas levels of 90-96% have frequently been quoted in the literature. Calculations of the latter numbers were incorrectly based on combined data for the Middle and Late Permian mass extinctions. About 90 orders and more than 220 families of marine animals survived the terminal Permian crisis, and they embodied an enormous amount of morphological, physiological, and ecological diversity. Life did not nearly disappear at the end of the Permian, as has often been claimed.

  14. Climate variability and increase in intensity and magnitude of dengue incidence in Singapore.

    Science.gov (United States)

    Hii, Yien Ling; Rocklöv, Joacim; Ng, Nawi; Tang, Choon Siang; Pang, Fung Yin; Sauerborn, Rainer

    2009-11-11

    Dengue is currently a major public health burden in Asia Pacific Region. This study aims to establish an association between dengue incidence, mean temperature and precipitation, and further discuss how weather predictors influence the increase in intensity and magnitude of dengue in Singapore during the period 2000-2007. Weekly dengue incidence data, daily mean temperature and precipitation and the midyear population data in Singapore during 2000-2007 were retrieved and analysed. We employed a time series Poisson regression model including time factors such as time trends, lagged terms of weather predictors, considered autocorrelation, and accounted for changes in population size by offsetting. The weekly mean temperature and cumulative precipitation were statistically significant related to the increases of dengue incidence in Singapore. Our findings showed that dengue incidence increased linearly at time lag of 5-16 and 5-20 weeks succeeding elevated temperature and precipitation, respectively. However, negative association occurred at lag week 17-20 with low weekly mean temperature as well as lag week 1-4 and 17-20 with low cumulative precipitation. As Singapore experienced higher weekly mean temperature and cumulative precipitation in the years 2004-2007, our results signified hazardous impacts of climate factors on the increase in intensity and magnitude of dengue cases. The ongoing global climate change might potentially increase the burden of dengue fever infection in near future.

  15. Forecasting the magnitude and onset of El Niño based on climate network

    Science.gov (United States)

    Meng, Jun; Fan, Jingfang; Ashkenazy, Yosef; Bunde, Armin; Havlin, Shlomo

    2018-04-01

    El Niño is probably the most influential climate phenomenon on inter-annual time scales. It affects the global climate system and is associated with natural disasters; it has serious consequences in many aspects of human life. However, the forecasting of the onset and in particular the magnitude of El Niño are still not accurate enough, at least more than half a year ahead. Here, we introduce a new forecasting index based on climate network links representing the similarity of low frequency temporal temperature anomaly variations between different sites in the Niño 3.4 region. We find that significant upward trends in our index forecast the onset of El Niño approximately 1 year ahead, and the highest peak since the end of last El Niño in our index forecasts the magnitude of the following event. We study the forecasting capability of the proposed index on several datasets, including, ERA-Interim, NCEP Reanalysis I, PCMDI-AMIP 1.1.3 and ERSST.v5.

  16. Physician work intensity among medical specialties: emerging evidence on its magnitude and composition.

    Science.gov (United States)

    Horner, Ronnie D; Szaflarski, Jerzy P; Ying, Jun; Meganathan, Karthikeyan; Matthews, Gerald; Schroer, Brian; Weber, Debra; Raphaelson, Marc

    2011-11-01

    Similarities and differences in physician work intensity among specialties are poorly understood but have implications for quality of care, patient safety, practice organization and management, and payment. To determine the magnitude and important dimensions of physician work intensity for 4 specialties. Cross-sectional assessment of work intensity associated with actual patient care in the examination room or operating room. A convenience sample of 45 family physicians, 20 general internists, 22 neurologists, and 21 surgeons, located in Kansas, Kentucky, Maryland, Ohio, and Virginia. Work intensity measures included the National Aeronautics and Space Administration-Task Load Index (NASA-TLX), Subjective Work Assessment Technique (SWAT), and Multiple Resource Questionnaire. Stress was measured by the Dundee Stress State Questionnaire. Physicians reported similar magnitude of work intensity on the NASA-TLX and Multiple Resource Questionnaire. On the SWAT, general internists reported work intensity similar to surgeons but significantly lower than family physicians and neurologists (P=0.035). Surgeons reported significantly higher levels of task engagement on the stress measure than the other specialties (P=0.019), significantly higher intensity on physical demand (P NASA-TLX than the other specialties (P=0.003). Surgeons reported the lowest intensity for temporal demand of all specialties, being significantly lower than either family physicians or neurologists (P=0.014). Family physicians reported the highest intensity on the time dimension of the SWAT, being significantly higher than either general internists or surgeons (P=0.008). Level of physician work intensity seems to be similar among specialties.

  17. Interaction of Volcanic Forcing and El Nino: Sensitivity to the Eruption Magnitude and El Nino Intensity

    KAUST Repository

    Predybaylo, Evgeniya; Wittenberg, Andrew; Stenchikov, Georgiy L.

    2015-01-01

    Volcanic aerosols formed in the stratosphere after strong explosive eruptions influence Earth's radiative balance, affecting atmospheric and oceanic temperatures and circulation. It was observed that the recent volcanic eruptions frequently occurred in El Nino years. Analysis of the paleo data confirms that the probability of a sequent El Nino occurrence after the eruption increases. To better understand the physical mechanism of this interaction we employed ocean-atmosphere coupled climate model CM2.1, developed in the Geophysical Fluid Dynamics Laboratory, and conducted a series of numerical experiments using initial conditions with different El Nino Southern Oscillation (ENSO) strengths forced by volcanic eruptions of different magnitudes, Pinatubo of June 1991 and Tambora of April 1815: (i) strong ENSO/Pinatubo, (ii) weak ENSO/Pinatubo, (iii) strong ENSO/Tambora. The amount of ejected material from the Tambora eruption was about three times greater than that of the Pinatubo eruption. The initial conditions with El Nino were sampled from the CM2.1 long control run. Our simulations show the enhancement of El Nino in the second year after an eruption. We found that the spatial-temporal structure of model responses is sensitive to both the magnitude of an eruption and the strength of El Nino. We analyzed the ocean dynamic in the tropical Pacific for all cases to uncover the physical mechanism, resulting in the enhanced and/or prolonged El Nino.

  18. Reliabilty worth: Development of a relationship with outage magnitude, duration and frequency

    International Nuclear Information System (INIS)

    Turner, F.P.P.; Katrichak, A.M.; Dwyer, A.; Edwards, D.; Ibrahim, A.

    1994-01-01

    British Columbia Hydro's Worth Project Team was founded to determine values for reliability for reference in evaluation of investment and operating decisions. Work to date has produced key preliminary values for specific outages and concepts for the shape of the relationship between value and these determinates of reliability worth, frequency, magnitude and duration. These values and concepts are described. The values are developed through an iterative, trial and refinement approach. The approach incorporates direct input from customers, common sense and judgement, and micro- and macro-economic concepts. Reliability worth values for reduced or prevented outages are presented for residential, commercial, small industrial and mixed sectors and various outage durations. Reliability worth values were obtained through customer surveys. Limitations of the reliability worth value are numerous and are listed. Study of cost vs magnitude of interruption using microeconomic models has shown that costly system improvements to reduce the possibility of widespread outages may not be justified. The case of exceptionally large area outages (blackouts) is examined. The cost vs frequency relationship was examined in terms of the economic concept of utility or satisfaction. Different loss/frequency characteristics are demonstrated for different customer classes. Customer value for reduced outage duration is expressed in a curve with flatter slope than that for eliminated outages. 2 refs., 6 figs

  19. Sum of the Magnitude for Hard Decision Decoding Algorithm Based on Loop Update Detection.

    Science.gov (United States)

    Meng, Jiahui; Zhao, Danfeng; Tian, Hai; Zhang, Liang

    2018-01-15

    In order to improve the performance of non-binary low-density parity check codes (LDPC) hard decision decoding algorithm and to reduce the complexity of decoding, a sum of the magnitude for hard decision decoding algorithm based on loop update detection is proposed. This will also ensure the reliability, stability and high transmission rate of 5G mobile communication. The algorithm is based on the hard decision decoding algorithm (HDA) and uses the soft information from the channel to calculate the reliability, while the sum of the variable nodes' (VN) magnitude is excluded for computing the reliability of the parity checks. At the same time, the reliability information of the variable node is considered and the loop update detection algorithm is introduced. The bit corresponding to the error code word is flipped multiple times, before this is searched in the order of most likely error probability to finally find the correct code word. Simulation results show that the performance of one of the improved schemes is better than the weighted symbol flipping (WSF) algorithm under different hexadecimal numbers by about 2.2 dB and 2.35 dB at the bit error rate (BER) of 10 -5 over an additive white Gaussian noise (AWGN) channel, respectively. Furthermore, the average number of decoding iterations is significantly reduced.

  20. A New Empirical Relation between Surface Wave Magnitude and Rupture Length for Turkey Earthquakes

    Directory of Open Access Journals (Sweden)

    Serkan Ozturk

    2014-01-01

    Full Text Available Many practical problems encountered in quantitative oriented disciplines entail finding the best approximate solution to an over determined system of linear equations. In this study, it is investigated the usage of different regression methods as a theoretical, practical and correct estimation tool in order to obtain the best empirical relationship between surface wave magnitude and rupture length for Turkey earthquakes. For this purpose, a detailed comparison is made among four different regression norms: (1 Least Squares, (2 Least Sum of Absolute Deviations, (3 Total Least Squares or Orthogonal and, (4 Robust Regressions. In order to assess the quality of the fit in a linear regression and to select the best empirical relationship for data sets, the correlation coefficient as a quite simple and very practicable tool is used. A list of all earthquakes where the surface wave magnitude (Ms and surface rupture length (L are available is compiled. In order to estimate the empirical relationships between these parameters for Turkey earthquakes, log-linear fit is used and following equations are derived from different norms: for L2 Norm regression (R2=0.71, for L1 Norm regression (R2=0.92, for Robust regression (R2=0.75, for Orthogonal regression (R2=0.68,                            Consequently, the empirical equation given by the Least Sum of Absolute Deviations regression as  with a strong correlation coefficient (R2=0.92 can be thought as more suitable and more reliable for Turkey earthquakes. Also, local differences in rupture length for a given magnitude can be interpreted in terms of local variation in geologic and seismic efficiencies.  Furthermore, this result suggests that seismic efficiency in a region is dependent on rupture length or magnitude.    Resumen Muchos problemas prácticos encontrados en las disciplinas de orientación cuantitativa implican encontrar la mejor solución aproximada para un sistema

  1. Trunk muscle activation. The effects of torso flexion, moment direction, and moment magnitude.

    Science.gov (United States)

    Lavender, S; Trafimow, J; Andersson, G B; Mayer, R S; Chen, I H

    1994-04-01

    This study was performed to quantify the electromyographic trunk muscle activities in response to variations in moment magnitude and direction while in forward-flexed postures. Recordings were made over eight trunk muscles in 19 subjects who maintained forward-flexed postures of 30 degrees and 60 degrees. In each of the two flexed postures, external moments of 20 Nm and 40 Nm were applied via a chest harness. The moment directions were varied in seven 30 degrees increments to a subject's right side, such that the direction of the applied load ranged from the upper body's anterior midsagittal plane (0 degree) to the posterior midsagittal plane (180 degrees). Statistical analyses yielded significant moment magnitude by moment-direction interaction effects for the EMG output from six of the eight muscles. Trunk flexion by moment-direction interactions were observed in the responses from three muscles. In general, the primary muscle supporting the torso and the applied load was the contralateral (left) erector spinae. The level of electromyographic activity in the anterior muscles was quite low, even with the posterior moment directions.

  2. Three-dimensional analyses of human bite-force magnitude and moment.

    Science.gov (United States)

    van Eijden, T M

    1991-01-01

    The effect of the three-dimensional orientation of occlusal force on maximal bite-force magnitude was examined in seven human subjects at three different unilateral anteroposterior bite positions (canine, second premolar and second molar). At each position, bite-force magnitude was registered in 17 precisely defined directions using a three-component force transducer and a feedback method. In addition, to assess the efficiency of transfer of muscle to bite force, for bites produced in the sagittal plane, moment-arm length was determined and the produced bite-force moment calculated. The results showed that the largest possible bite force was not always produced in a direction perpendicular to the occlusal plane. Generally, maximal bite force in medial and posterior directions was larger than that in, respectively, corresponding lateral and anterior directions. In each direction the produced force was larger at the posterior bite point than at the anterior bite point. The combined moment produced by the jaw muscles was largest for vertical bites, smallest for posteriorly directed bites and intermediate for anteriorly directed bites. In the case of vertically and anteriorly directed bites the produced moment did not vary significantly with the bite position. Hence, for these bite positions the jaw closing moment of the muscles must have kept constant. In the case of posteriorly directed bites the produced moment decreased when bite position changed from the anterior to the posterior side of the dentition. This indicated that jaw muscle activity had declined.

  3. Relationship Between Magnitude of Applied Spin Recovery Moment and Ensuing Number of Recovery Turns

    Science.gov (United States)

    Anglin, Ernie L.

    1967-01-01

    An analytical study has been made to investigate the relationship between the magnitude of the applied spin recovery moment and the ensuing number of turns made during recovery from a developed spin with a view toward determining how to interpolate or extrapolate spin recovery results with regard to determining the amount of control required for a satisfactory recovery. Five configurations were used which are considered to be representative of modern airplanes: a delta-wing fighter, a stub-wing research vehicle, a boostglide configuration, a supersonic trainer, and a sweptback-wing fighter. The results obtained indicate that there is a direct relationship between the magnitude of the applied spin recovery moments and the ensuing number of recovery turns made and that this relationship can be expressed in either simple multiplicative or exponential form. Either type of relationship was adequate for interpolating or extrapolating to predict turns required for recovery with satisfactory accuracy for configurations having relatively steady recovery motions. Any two recoveries from the same developed spin condition can be used as a basis for the predicted results provided these recoveries are obtained with the same ratio of recovery control deflections. No such predictive method can be expected to give satisfactory results for oscillatory recoveries.

  4. Reevaluation of the macroseismic effects of the 1887 Sonora, Mexico earthquake and its magnitude estimation

    Science.gov (United States)

    Suárez, Gerardo; Hough, Susan E.

    2008-01-01

    The Sonora, Mexico, earthquake of 3 May 1887 occurred a few years before the start of the instrumental era in seismology. We revisit all available accounts of the earthquake and assign Modified Mercalli Intensities (MMI), interpreting and analyzing macroseismic information using the best available modern methods. We find that earlier intensity assignments for this important earthquake were unjustifiably high in many cases. High intensity values were assigned based on accounts of rock falls, soil failure or changes in the water table, which are now known to be very poor indicators of shaking severity and intensity. Nonetheless, reliable accounts reveal that light damage (intensity VI) occurred at distances of up to ~200 km in both Mexico and the United States. The resulting set of 98 reevaluated intensity values is used to draw an isoseismal map of this event. Using the attenuation relation proposed by Bakun (2006b), we estimate an optimal moment magnitude of Mw7.6. Assuming this magnitude is correct, a fact supported independently by documented rupture parameters assuming standard scaling relations, our results support the conclusion that northern Sonora as well as the Basin and Range province are characterized by lower attenuation of intensities than California. However, this appears to be at odds with recent results that Lg attenuation in the Basin and Range province is comparable to that in California.

  5. The Effect of Amplifier Bias Drift on Differential Magnitude Estimation in Multiple-Star Systems

    Science.gov (United States)

    Tyler, David W.; Muralimanohar, Hariharan; Borelli, Kathy J.

    2007-02-01

    We show how the temporal drift of CCD amplifier bias can cause significant relative magnitude estimation error in speckle interferometric observations of multiple-star systems. When amplifier bias varies over time, the estimation error arises if the time between acquisition of dark-frame calibration data and science data is long relative to the timescale over which the bias changes. Using analysis, we show that while detector-temperature drift over time causes a variation in accumulated dark current and a residual bias in calibrated imagery, only amplifier bias variations cause a residual bias in the estimated energy spectrum. We then use telescope data taken specifically to investigate this phenomenon to show that for the detector used, temporal bias drift can cause residual energy spectrum bias as large or larger than the mean value of the noise energy spectrum. Finally, we use a computer simulation to demonstrate the effect of residual bias on differential magnitude estimation. A supplemental calibration technique is described in the appendices.

  6. Correlations in magnitude series to assess nonlinearities: Application to multifractal models and heartbeat fluctuations

    Science.gov (United States)

    Bernaola-Galván, Pedro A.; Gómez-Extremera, Manuel; Romance, A. Ramón; Carpena, Pedro

    2017-09-01

    The correlation properties of the magnitude of a time series are associated with nonlinear and multifractal properties and have been applied in a great variety of fields. Here we have obtained the analytical expression of the autocorrelation of the magnitude series (C|x |) of a linear Gaussian noise as a function of its autocorrelation (Cx). For both, models and natural signals, the deviation of C|x | from its expectation in linear Gaussian noises can be used as an index of nonlinearity that can be applied to relatively short records and does not require the presence of scaling in the time series under study. In a model of artificial Gaussian multifractal signal we use this approach to analyze the relation between nonlinearity and multifractallity and show that the former implies the latter but the reverse is not true. We also apply this approach to analyze experimental data: heart-beat records during rest and moderate exercise. For each individual subject, we observe higher nonlinearities during rest. This behavior is also achieved on average for the analyzed set of 10 semiprofessional soccer players. This result agrees with the fact that other measures of complexity are dramatically reduced during exercise and can shed light on its relationship with the withdrawal of parasympathetic tone and/or the activation of sympathetic activity during physical activity.

  7. Orthodontically induced osteocyte apoptosis under different force magnitudes in rats: an immunohistochemical study.

    Science.gov (United States)

    Kassem, Hassan E; Talaat, Iman M; El-Sawa, Afaf; Ismail, Hanan; Zaher, Abbas

    2017-10-01

    We investigated the effect of different force magnitudes on osteocyte apoptosis in a model of orthodontic tooth movement. Forty-nine male Sprague Dawley rats (7-9 wk of age) were divided into light- and heavy-force groups (n = 21 each group) and a control group (n = 7). A coil spring delivered pressure (either 10-15 g or 20-25 g) to the left maxillary first molar. The rats were sacrificed 1, 3, or 5 d after placement of the appliance. Sections of the maxillary first molars were immunostained for caspase-3. Upon force application, the number of apoptotic osteocytes significantly increased in the pressure side at 1 d and remained the same at 3 d and 5 d. However, there was no significant difference in the number of apoptotic osteocytes between the two force groups. We conclude that osteocyte apoptosis appears to increase under orthodontic loading, reaching a plateau after 1 d. However, osteocyte apoptosis seems to be independent of the magnitude of orthodontic forces tested. © 2017 Eur J Oral Sci.

  8. Addressing Phase Errors in Fat-Water Imaging Using a Mixed Magnitude/Complex Fitting Method

    Science.gov (United States)

    Hernando, D.; Hines, C. D. G.; Yu, H.; Reeder, S.B.

    2012-01-01

    Accurate, noninvasive measurements of liver fat content are needed for the early diagnosis and quantitative staging of nonalcoholic fatty liver disease. Chemical shift-based fat quantification methods acquire images at multiple echo times using a multiecho spoiled gradient echo sequence, and provide fat fraction measurements through postprocessing. However, phase errors, such as those caused by eddy currents, can adversely affect fat quantification. These phase errors are typically most significant at the first echo of the echo train, and introduce bias in complex-based fat quantification techniques. These errors can be overcome using a magnitude-based technique (where the phase of all echoes is discarded), but at the cost of significantly degraded signal-to-noise ratio, particularly for certain choices of echo time combinations. In this work, we develop a reconstruction method that overcomes these phase errors without the signal-to-noise ratio penalty incurred by magnitude fitting. This method discards the phase of the first echo (which is often corrupted) while maintaining the phase of the remaining echoes (where phase is unaltered). We test the proposed method on 104 patient liver datasets (from 52 patients, each scanned twice), where the fat fraction measurements are compared to coregistered spectroscopy measurements. We demonstrate that mixed fitting is able to provide accurate fat fraction measurements with high signal-to-noise ratio and low bias over a wide choice of echo combinations. PMID:21713978

  9. Validation of SplitVectors Encoding for Quantitative Visualization of Large-Magnitude-Range Vector Fields.

    Science.gov (United States)

    Henan Zhao; Bryant, Garnett W; Griffin, Wesley; Terrill, Judith E; Jian Chen

    2017-06-01

    We designed and evaluated SplitVectors, a new vector field display approach to help scientists perform new discrimination tasks on large-magnitude-range scientific data shown in three-dimensional (3D) visualization environments. SplitVectors uses scientific notation to display vector magnitude, thus improving legibility. We present an empirical study comparing the SplitVectors approach with three other approaches - direct linear representation, logarithmic, and text display commonly used in scientific visualizations. Twenty participants performed three domain analysis tasks: reading numerical values (a discrimination task), finding the ratio between values (a discrimination task), and finding the larger of two vectors (a pattern detection task). Participants used both mono and stereo conditions. Our results suggest the following: (1) SplitVectors improve accuracy by about 10 times compared to linear mapping and by four times to logarithmic in discrimination tasks; (2) SplitVectors have no significant differences from the textual display approach, but reduce cluttering in the scene; (3) SplitVectors and textual display are less sensitive to data scale than linear and logarithmic approaches; (4) using logarithmic can be problematic as participants' confidence was as high as directly reading from the textual display, but their accuracy was poor; and (5) Stereoscopy improved performance, especially in more challenging discrimination tasks.

  10. Stimulus fear relevance and the speed, magnitude, and robustness of vicariously learned fear.

    Science.gov (United States)

    Dunne, Güler; Reynolds, Gemma; Askew, Chris

    2017-08-01

    Superior learning for fear-relevant stimuli is typically indicated in the laboratory by faster acquisition of fear responses, greater learned fear, and enhanced resistance to extinction. Three experiments investigated the speed, magnitude, and robustness of UK children's (6-10 years; N = 290; 122 boys, 168 girls) vicariously learned fear responses for three types of stimuli. In two experiments, children were presented with pictures of novel animals (Australian marsupials) and flowers (fear-irrelevant stimuli) alone (control) or together with faces expressing fear or happiness. To determine learning speed the number of stimulus-face pairings seen by children was varied (1, 10, or 30 trials). Robustness of learning was examined via repeated extinction procedures over 3 weeks. A third experiment compared the magnitude and robustness of vicarious fear learning for snakes and marsupials. Significant increases in fear responses were found for snakes, marsupials and flowers. There was no indication that vicarious learning for marsupials was faster than for flowers. Moreover, vicariously learned fear was neither greater nor more robust for snakes compared to marsupials, or for marsupials compared to flowers. These findings suggest that for this age group stimulus fear relevance may have little influence on vicarious fear learning. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. THE EFFECT OF DRY MERGERS ON THE COLOR-MAGNITUDE RELATION OF EARLY-TYPE GALAXIES

    International Nuclear Information System (INIS)

    Skelton, Rosalind E.; Bell, Eric F.; Somerville, Rachel S.

    2009-01-01

    We investigate the effect of dry merging on the color-magnitude relation (CMR) of galaxies and find that the amount of merging predicted by a hierarchical model results in a red sequence that compares well with the observed low-redshift relation. A sample of ∼ 29,000 early-type galaxies selected from the Sloan Digital Sky Survey Data Release 6 shows that the bright end of the CMR has a shallower slope and smaller scatter than the faint end. This magnitude dependence is predicted by a simple toy model in which gas-rich mergers move galaxies onto a 'creation red sequence' (CRS) by quenching their star formation, and subsequent mergers between red, gas-poor galaxies (so-called 'dry' mergers) move galaxies along the relation. We use galaxy merger trees from a semianalytic model of galaxy formation to test the amplitude of this effect and find a change in slope at the bright end that brackets the observations, using gas fraction thresholds of 10%-30% to separate wet and dry mergers. A more realistic model that includes scatter in the CRS shows that dry merging decreases the scatter at the bright end. Contrary to previous claims, the small scatter in the observed CMR thus cannot be used to constrain the amount of dry merging.

  12. Sum of the Magnitude for Hard Decision Decoding Algorithm Based on Loop Update Detection

    Directory of Open Access Journals (Sweden)

    Jiahui Meng

    2018-01-01

    Full Text Available In order to improve the performance of non-binary low-density parity check codes (LDPC hard decision decoding algorithm and to reduce the complexity of decoding, a sum of the magnitude for hard decision decoding algorithm based on loop update detection is proposed. This will also ensure the reliability, stability and high transmission rate of 5G mobile communication. The algorithm is based on the hard decision decoding algorithm (HDA and uses the soft information from the channel to calculate the reliability, while the sum of the variable nodes’ (VN magnitude is excluded for computing the reliability of the parity checks. At the same time, the reliability information of the variable node is considered and the loop update detection algorithm is introduced. The bit corresponding to the error code word is flipped multiple times, before this is searched in the order of most likely error probability to finally find the correct code word. Simulation results show that the performance of one of the improved schemes is better than the weighted symbol flipping (WSF algorithm under different hexadecimal numbers by about 2.2 dB and 2.35 dB at the bit error rate (BER of 10−5 over an additive white Gaussian noise (AWGN channel, respectively. Furthermore, the average number of decoding iterations is significantly reduced.

  13. Estimates of the magnitudes of major marine mass extinctions in earth history.

    Science.gov (United States)

    Stanley, Steven M

    2016-10-18

    Procedures introduced here make it possible, first, to show that background (piecemeal) extinction is recorded throughout geologic stages and substages (not all extinction has occurred suddenly at the ends of such intervals); second, to separate out background extinction from mass extinction for a major crisis in earth history; and third, to correct for clustering of extinctions when using the rarefaction method to estimate the percentage of species lost in a mass extinction. Also presented here is a method for estimating the magnitude of the Signor-Lipps effect, which is the incorrect assignment of extinctions that occurred during a crisis to an interval preceding the crisis because of the incompleteness of the fossil record. Estimates for the magnitudes of mass extinctions presented here are in most cases lower than those previously published. They indicate that only ∼81% of marine species died out in the great terminal Permian crisis, whereas levels of 90-96% have frequently been quoted in the literature. Calculations of the latter numbers were incorrectly based on combined data for the Middle and Late Permian mass extinctions. About 90 orders and more than 220 families of marine animals survived the terminal Permian crisis, and they embodied an enormous amount of morphological, physiological, and ecological diversity. Life did not nearly disappear at the end of the Permian, as has often been claimed.

  14. Southern San Andreas Fault seismicity is consistent with the Gutenberg-Richter magnitude-frequency distribution

    Science.gov (United States)

    Page, Morgan T.; Felzer, Karen

    2015-01-01

    The magnitudes of any collection of earthquakes nucleating in a region are generally observed to follow the Gutenberg-Richter (G-R) distribution. On some major faults, however, paleoseismic rates are higher than a G-R extrapolation from the modern rate of small earthquakes would predict. This, along with other observations, led to formulation of the characteristic earthquake hypothesis, which holds that the rate of small to moderate earthquakes is permanently low on large faults relative to the large-earthquake rate (Wesnousky et al., 1983; Schwartz and Coppersmith, 1984). We examine the rate difference between recent small to moderate earthquakes on the southern San Andreas fault (SSAF) and the paleoseismic record, hypothesizing that the discrepancy can be explained as a rate change in time rather than a deviation from G-R statistics. We find that with reasonable assumptions, the rate changes necessary to bring the small and large earthquake rates into alignment agree with the size of rate changes seen in epidemic-type aftershock sequence (ETAS) modeling, where aftershock triggering of large earthquakes drives strong fluctuations in the seismicity rates for earthquakes of all magnitudes. The necessary rate changes are also comparable to rate changes observed for other faults worldwide. These results are consistent with paleoseismic observations of temporally clustered bursts of large earthquakes on the SSAF and the absence of M greater than or equal to 7 earthquakes on the SSAF since 1857.

  15. Earthquake Magnitude and Shaking Intensity Dependent Fragility Functions for Rapid Risk Assessment of Buildings

    Directory of Open Access Journals (Sweden)

    Marie-José Nollet

    2018-01-01

    Full Text Available An integrated web application, referred to as ER2 for rapid risk evaluator, is under development for a user-friendly seismic risk assessment by the non-expert public safety community. The assessment of likely negative consequences is based on pre-populated databases of seismic, building inventory and vulnerability parameters. To further accelerate the computation for near real-time analyses, implicit building fragility curves were developed as functions of the magnitude and the intensity of the seismic shaking defined with a single intensity measure, input spectral acceleration at 1.0 s implicitly considering the epicentral distance and local soil conditions. Damage probabilities were compared with those obtained with the standard fragility functions explicitly considering epicentral distances and local site classes in addition to the earthquake magnitudes and respective intensity of the seismic shaking. Different seismic scenarios were considered first for 53 building classes common in Eastern Canada, and then a reduced number of 24 combined building classes was proposed. Comparison of results indicate that the damage predictions with implicit fragility functions for short (M ≤ 5.5 and medium strong motion duration (5.5 < M ≤ 7.5 show low variation with distance and soil class, with average error of less than 3.6%.

  16. Kompetisi Stasiun Televisi Swasta Nasional Berdasarkan Superiority Direction dan Superiority Magnitude

    Directory of Open Access Journals (Sweden)

    Anastasia Winanti Riesardhy

    2013-11-01

    Full Text Available Abstract: Uses and gratification theory is employed particularly as the teoritical frame of the research to examine the extent to which ten national television stations compete to satisfy Indonesian audiences. In particular, two main concepts of that theory namely audiences “gratification sought and gratifications obtained, are broken down and counted based on superiority direction and superiority magnitude. In general, the findings show that those televisions have satisfied their audiences, although in terms of gratifications to dispersal motives, they haven’t satisfied as much as it was expected. Significant competition occurs between TRANSTV and TRANS7, RCTI and SCTV, and TVONE and METROTV. TVONE become the most satisfiyng television station. Abstrak: Teori Uses & Gratification menjadi dasar penelitian ini untuk mengukur bagaimana kompetisi yang terjadi di antara sepuluh stasiun televisi yang bersiaran secara nasional di Indonesia. Aplikasi dari teori tersebut dimunculkan dalam konsep kepuasan yang diharapkan dan kepuasan yang diperoleh ketika menonton acara televisi dan didasarkan pada penghitungan superiority direction dan superiority magnitude. Sepuluh stasiun televisi yang diteliti telah dapat memuaskan audiensnya, meskipun untuk kepuasan atas motif pengalihan masih belum dapat melampaui kepuasan yang diharapkan. Kompetisi yang signifikan terjadi antara TRANSTV dengan TRANS7, RCTI dengan SCTV serta TVONE dengan METROTV. TVONE menjadi stasiun televisi yang menduduki peringkat pertama dalam memberikan kepuasan tertinggi kepada audiens.

  17. Structure of the Large Magellanic Cloud from near infrared magnitudes of red clump stars

    Science.gov (United States)

    Subramanian, S.; Subramaniam, A.

    2013-04-01

    Context. The structural parameters of the disk of the Large Magellanic Cloud (LMC) are estimated. Aims: We used the JH photometric data of red clump (RC) stars from the Magellanic Cloud Point Source Catalog (MCPSC) obtained from the InfraRed Survey Facility (IRSF) to estimate the structural parameters of the LMC disk, such as the inclination, i, and the position angle of the line of nodes (PAlon), φ. Methods: The observed LMC region is divided into several sub-regions, and stars in each region are cross-identified with the optically identified RC stars to obtain the near infrared magnitudes. The peak values of H magnitude and (J - H) colour of the observed RC distribution are obtained by fitting a profile to the distributions and by taking the average value of magnitude and colour of the RC stars in the bin with largest number. Then the dereddened peak H0 magnitude of the RC stars in each sub-region is obtained from the peak values of H magnitude and (J - H) colour of the observed RC distribution. The right ascension (RA), declination (Dec), and relative distance from the centre of each sub-region are converted into x,y, and z Cartesian coordinates. A weighted least square plane fitting method is applied to this x,y,z data to estimate the structural parameters of the LMC disk. Results: An intrinsic (J - H)0 colour of 0.40 ± 0.03 mag in the Simultaneous three-colour InfraRed Imager for Unbiased Survey (SIRIUS) IRSF filter system is estimated for the RC stars in the LMC and a reddening map based on (J - H) colour of the RC stars is presented. When the peaks of the RC distribution were identified by averaging, an inclination of 25°.7 ± 1°.6 and a PAlon = 141°.5 ± 4°.5 were obtained. We estimate a distance modulus, μ = 18.47 ± 0.1 mag to the LMC. Extra-planar features which are both in front and behind the fitted plane are identified. They match with the optically identified extra-planar features. The bar of the LMC is found to be part of the disk within 500

  18. A moment-tensor catalog for intermediate magnitude earthquakes in Mexico

    Science.gov (United States)

    Rodríguez Cardozo, Félix; Hjörleifsdóttir, Vala; Martínez-Peláez, Liliana; Franco, Sara; Iglesias Mendoza, Arturo

    2016-04-01

    Located among five tectonic plates, Mexico is one of the world's most seismically active regions. The earthquake focal mechanisms provide important information on the active tectonics. A widespread technique for estimating the earthquake magnitud and focal mechanism is the inversion for the moment tensor, obtained by minimizing a misfit function that estimates the difference between synthetic and observed seismograms. An important element in the estimation of the moment tensor is an appropriate velocity model, which allows for the calculation of accurate Green's Functions so that the differences between observed and synthetics seismograms are due to the source of the earthquake rather than the velocity model. However, calculating accurate synthetic seismograms gets progressively more difficult as the magnitude of the earthquakes decreases. Large earthquakes (M>5.0) excite waves of longer periods that interact weakly with lateral heterogeneities in the crust. For these events, using 1D velocity models to compute Greens functions works well and they are well characterized by seismic moment tensors reported in global catalogs (eg. USGS fast moment tensor solutions and GCMT). The opposite occurs for small and intermediate sized events, where the relatively shorter periods excited interact strongly with lateral heterogeneities in the crust and upper mantle. To accurately model the Green's functions for the smaller events in a large heterogeneous area, requires 3D or regionalized 1D models. To obtain a rapid estimate of earthquake magnitude, the National Seismological Survey in Mexico (Servicio Sismológico Nacional, SSN) automatically calculates seismic moment tensors for events in the Mexican Territory (Franco et al., 2002; Nolasco-Carteño, 2006). However, for intermediate-magnitude and small earthquakes the signal-to-noise ratio could is low for many of the seismic stations, and without careful selection and filtering of the data, obtaining a stable focal mechanism

  19. The role of short-term memory and visuo-spatial skills in numerical magnitude processing: Evidence from Turner syndrome.

    Directory of Open Access Journals (Sweden)

    Lucie Attout

    Full Text Available Most studies on magnitude representation have focused on the visual modality with no possibility of disentangling the influence of visuo-spatial skills and short-term memory (STM abilities on quantification processes. This study examines this issue in patients with Turner syndrome (TS, a genetic condition characterized by a specific cognitive profile frequently associating poor mathematical achievement, low spatial skills and reduced STM abilities. In order to identify the influence of visuo-spatial and STM processing on numerical magnitude abilities, twenty female participants with TS and twenty control female participants matched for verbal IQ and education level were administered a series of magnitude comparison tasks. The tasks differed on the nature of the magnitude to be processed (continuous, discrete and symbolic magnitude, on visuo-spatial processing requirement (no/high and on STM demands (low in simultaneous presentation vs. high in sequential presentation. Our results showed a lower acuity when participants with TS compared the numerical magnitudes of stimuli presented sequentially (low visuo-spatial processing and high STM load: Dot sequence and Sound sequence while no difference was observed in the numerical comparison of sets presented simultaneously. In addition, the group difference in sequential tasks disappeared when controlling for STM abilities. Finally, both groups demonstrated similar performance when comparing continuous or symbolic magnitude stimuli and they exhibited comparable subitizing abilities. These results highlight the importance of STM abilities in extracting numerosity through a sequential presentation and underline the importance of considering the impact of format presentation on magnitude judgments.

  20. Foundations of children's numerical and mathematical skills: the roles of symbolic and nonsymbolic representations of numerical magnitude.

    Science.gov (United States)

    Lyons, Ian M; Ansari, Daniel

    2015-01-01

    Numerical and mathematical skills are critical predictors of academic success. The last three decades have seen a substantial growth in our understanding of how the human mind and brain represent and process numbers. In particular, research has shown that we share with animals the ability to represent numerical magnitude (the total number of items in a set) and that preverbal infants can process numerical magnitude. Further research has shown that similar processing signatures characterize numerical magnitude processing across species and developmental time. These findings suggest that an approximate system for nonsymbolic (e.g., dot arrays) numerical magnitude representation serves as the basis for the acquisition of cultural, symbolic (e.g., Arabic numerals) representations of numerical magnitude. This chapter explores this hypothesis by reviewing studies that have examined the relation between individual differences in nonsymbolic numerical magnitude processing and symbolic math abilities (e.g., arithmetic). Furthermore, we examine the extent to which the available literature provides strong evidence for a link between symbolic and nonsymbolic representations of numerical magnitude at the behavioral and neural levels of analysis. We conclude that claims that symbolic number abilities are grounded in the approximate system for the nonsymbolic representation of numerical magnitude are not strongly supported by the available evidence. Alternative models and future research directions are discussed. © 2015 Elsevier Inc. All rights reserved.

  1. A Job with a Future? Delay Discounting, Magnitude Effects, and Domain Independence of Utility for Career Decisions.

    Science.gov (United States)

    Schoenfelder, Thomas E.; Hantula, Donald A.

    2003-01-01

    Seniors (n=20) assessed two job offers with differences in domain (salary/tasks), delay (career-long earnings), and magnitude (initial salary offer). Contrary to discounted utility theory, choices reflected nonconstant discount rates for future salary/tasks (delay effect), lower discount rates for salary/preferred tasks (magnitude effect), and a…

  2. The JHKs Magnitudes of the Red Giant Branch Tip and the Distance Moduli of Nearby Dwarf Galaxy NGC 205

    Directory of Open Access Journals (Sweden)

    M. Y. Jung

    2009-12-01

    Full Text Available We have used the near-infrared JHKS photometric data of resolved stars in a nearby dwarf elliptical galaxy NGC 205 to determine the magnitudes of the red giant branch tip (TRGB. By applying Savitzky-Golay filter to the observed luminosity functions (LFs in each band, we derived the second derivatives of the LFs so as to determine the magnitudes of the TRGB. Absolute magnitudes of the TRGB in JHKs bands were measured from the Yonsei-Yale isochrones. By comparing the determined apparent magnitudes and the theoretical absolute magnitudes of the TRGB, we estimated the distance moduli of NGC 205 to be (m-M = 24.10±0:08, 24.08±0.12 and 24.14±0.14 in J, H, and Ks bands, respectively.

  3. Magnitude and meaningfulness of change in SF-36 scores in four types of orthopedic surgery

    Directory of Open Access Journals (Sweden)

    Buchbinder Rachelle

    2008-07-01

    Full Text Available Abstract Background The Medical Outcomes General Health Survey (SF-36 is a widely used health status measure; however, limited evidence is available for its performance in orthopedic settings. The aim of this study was to examine the magnitude and meaningfulness of change and sensitivity of SF-36 subscales following orthopedic surgery. Methods Longitudinal data on outcomes of total hip replacement (THR, n = 255, total knee replacement (TKR, n = 103, arthroscopic partial meniscectomy (APM, n = 74 and anterior cruciate ligament reconstruction (ACL, n = 62 were used to estimate the effect sizes (ES, magnitude of change and minimal detectable change (sensitivity at the group and individual level. To provide context for interpreting the magnitude of changes in SF-36 scores, we also compared patients' scores with age and sex-matched population norms. The studies were conducted in Sweden. Follow-up was five years in THR and TKR studies, two years in ACL, and three months in APM. Results On average, large effect sizes (ES≥0.80 were found after orthopedic surgery in SF-36 subscales measuring physical aspects (physical functioning, role physical, and bodily pain. Small (0.20–0.49 to moderate (0.50–0.79 effect sizes were found in subscales measuring mental and social aspects (role emotional, vitality, social functioning, and mental health. General health scores remained relatively unchanged during the follow-up. Despite improvements, post-surgery mean scores of patients were still below the age and sex matched population norms on physical subscales. Patients' scores on mental and social subscales approached population norms following the surgery. At the individual level, scores of a large proportion of patients were affected by floor or ceiling effects on several subscales and the sensitivity to individual change was very low. Conclusion Large to moderate meaningful changes in group scores were observed in all SF-36 subscales except General Health

  4. Tests of the Tully-Fisher relation. 1: Scatter in infrared magnitude versus 21 cm width

    Science.gov (United States)

    Bernstein, Gary M.; Guhathakurta, Puragra; Raychaudhury, Somak; Giovanelli, Riccardo; Haynes, Martha P.; Herter, Terry; Vogt, Nicole P.

    1994-01-01

    We examine the precision of the Tully-Fisher relation (TFR) using a sample of galaxies in the Coma region of the sky, and find that it is good to 5% or better in measuring relative distances. Total magnitudes and disk axis ratios are derived from H and I band surface photometry, and Arecibo 21 cm profiles define the rotation speeds of the galaxies. Using 25 galaxies for which the disk inclination and 21 cm width are well defined, we find an rms deviation of 0.10 mag from a linear TFR with dI/d(log W(sub c)) = -5.6. Each galaxy is assumed to be at a distance proportional to its redshift, and an extinction correction of 1.4(1-b/a) mag is applied to the total I magnitude. The measured scatter is less than 0.15 mag using milder extinction laws from the literature. The I band TFR scatter is consistent with measurement error, and the 95% CL limits on the intrinsic scatter are 0-0.10 mag. The rms scatter using H band magnitudes is 0.20 mag (N = 17). The low width galaxies have scatter in H significantly in excess of known measurement error, but the higher width half of the galaxies have scatter consistent with measurement error. The H band TFR slope may be as steep as the I band slope. As the first applications of this tight correlation, we note the following: (1) the data for the particular spirals commonly used to define the TFR distance to the Coma cluster are inconsistent with being at a common distance and are in fact in free Hubble expansion, with an upper limit of 300 km/s on the rms peculiar line-of-sight velocity of these gas-rich spirals; and (2) the gravitational potential in the disks of these galaxies has typical ellipticity less than 5%. The published data for three nearby spiral galaxies with Cepheid distance determinations are inconsistent with our Coma TFR, suggesting that these local calibrators are either ill-measured or peculiar relative to the Coma Supercluster spirals, or that the TFR has a varying form in different locales.

  5. Method of Relative Magnitudes for Calculating Magnetic Fluxes in Electrical Machine

    Directory of Open Access Journals (Sweden)

    Oleg A.

    2018-03-01

    Full Text Available Introduction: The article presents the study results of the model of an asynchronous electric motor carried out by the author within the framework of the Priorities Research Program “Research and development in the priority areas of development of Russia’s scientific and technical complex for 2014–2020”. Materials and Methods: A model of an idealized asynchronous machine (with sinusoidal distribution of magnetic induction in air gap is used in vector control systems. It is impossible to create windings for this machine. The basis of the new calculation approach was the Conductivity of Teeth Contours Method, developed at the Electrical Machines Chair of the Moscow Power Engineering Institute (MPEI. Unlike this method, the author used not absolute values, but relative magnitudes of magnetic fluxes. This solution fundamentally improved the method’s capabilities. The relative magnitudes of the magnetic fluxes of the teeth contours do not required the additional consideration for exact structure of magnetic field of tooth and adjacent slots. These structures are identical for all the teeth of the machine and differ only in magnitude. The purpose of the calculations was not traditional harmonic analysis of magnetic induction distribution in air gap of machine, but a refinement of the equations of electric machine model. The vector control researchers used only the cos(θ function as a value of mutual magnetic coupling coefficient between the windings. Results: The author has developed a way to take into account the design of the windings of a real machine by using imaginary measuring winding with the same winding design as a real phase winding. The imaginary winding can be placed in the position of any machine windings. The calculation of the relative magnetic fluxes of this winding helped to estimate the real values of the magnetic coupling coefficients between the windings, and find the correction functions for the model of an idealized

  6. Methodology for Estimation of Flood Magnitude and Frequency for New Jersey Streams

    Science.gov (United States)

    Watson, Kara M.; Schopp, Robert D.

    2009-01-01

    Methodologies were developed for estimating flood magnitudes at the 2-, 5-, 10-, 25-, 50-, 100-, and 500-year recurrence intervals for unregulated or slightly regulated streams in New Jersey. Regression equations that incorporate basin characteristics were developed to estimate flood magnitude and frequency for streams throughout the State by use of a generalized least squares regression analysis. Relations between flood-frequency estimates based on streamflow-gaging-station discharge and basin characteristics were determined by multiple regression analysis, and weighted by effective years of record. The State was divided into five hydrologically similar regions to refine the regression equations. The regression analysis indicated that flood discharge, as determined by the streamflow-gaging-station annual peak flows, is related to the drainage area, main channel slope, percentage of lake and wetland areas in the basin, population density, and the flood-frequency region, at the 95-percent confidence level. The standard errors of estimate for the various recurrence-interval floods ranged from 48.1 to 62.7 percent. Annual-maximum peak flows observed at streamflow-gaging stations through water year 2007 and basin characteristics determined using geographic information system techniques for 254 streamflow-gaging stations were used for the regression analysis. Drainage areas of the streamflow-gaging stations range from 0.18 to 779 mi2. Peak-flow data and basin characteristics for 191 streamflow-gaging stations located in New Jersey were used, along with peak-flow data for stations located in adjoining States, including 25 stations in Pennsylvania, 17 stations in New York, 16 stations in Delaware, and 5 stations in Maryland. Streamflow records for selected stations outside of New Jersey were included in the present study because hydrologic, physiographic, and geologic boundaries commonly extend beyond political boundaries. The StreamStats web application was developed

  7. Trading Time with Space - Development of subduction zone parameter database for a maximum magnitude correlation assessment

    Science.gov (United States)

    Schaefer, Andreas; Wenzel, Friedemann

    2017-04-01

    Subduction zones are generally the sources of the earthquakes with the highest magnitudes. Not only in Japan or Chile, but also in Pakistan, the Solomon Islands or for the Lesser Antilles, subduction zones pose a significant hazard for the people. To understand the behavior of subduction zones, especially to identify their capabilities to produce maximum magnitude earthquakes, various physical models have been developed leading to a large number of various datasets, e.g. from geodesy, geomagnetics, structural geology, etc. There have been various studies to utilize this data for the compilation of a subduction zone parameters database, but mostly concentrating on only the major zones. Here, we compile the largest dataset of subduction zone parameters both in parameter diversity but also in the number of considered subduction zones. In total, more than 70 individual sources have been assessed and the aforementioned parametric data have been combined with seismological data and many more sources have been compiled leading to more than 60 individual parameters. Not all parameters have been resolved for each zone, since the data completeness depends on the data availability and quality for each source. In addition, the 3D down-dip geometry of a majority of the subduction zones has been resolved using historical earthquake hypocenter data and centroid moment tensors where available and additionally compared and verified with results from previous studies. With such a database, a statistical study has been undertaken to identify not only correlations between those parameters to estimate a parametric driven way to identify potentials for maximum possible magnitudes, but also to identify similarities between the sources themselves. This identification of similarities leads to a classification system for subduction zones. Here, it could be expected if two sources share enough common characteristics, other characteristics of interest may be similar as well. This concept

  8. Coda-derived source spectra, moment magnitudes and energy-moment scaling in the western Alps

    Science.gov (United States)

    Morasca, P.; Mayeda, K.; Malagnini, L.; Walter, William R.

    2005-01-01

    A stable estimate of the earthquake source spectra in the western Alps is obtained using an empirical method based on coda envelope amplitude measurements described by Mayeda et al. for events ranging between MW~ 1.0 and ~5.0. Path corrections for consecutive narrow frequency bands ranging between 0.3 and 25.0 Hz were included using a simple 1-D model for five three-component stations of the Regional Seismic network of Northwestern Italy (RSNI). The 1-D assumption performs well, even though the region is characterized by a complex structural setting involving strong lateral variations in the Moho depth. For frequencies less than 1.0 Hz, we tied our dimensionless, distance-corrected coda amplitudes to an absolute scale in units of dyne cm by using independent moment magnitudes from long-period waveform modelling for three moderate magnitude events in the region. For the higher frequencies, we used small events as empirical Green's functions, with corner frequencies above 25.0 Hz. For each station, the procedure yields frequency-dependent corrections that account for site effects, including those related to fmax, as well as to S-to-coda transfer function effects. After the calibration was completed, the corrections were applied to the entire data set composed of 957 events. Our findings using the coda-derived source spectra are summarized as follows: (i) we derived stable estimates of seismic moment, M0, (and hence MW) as well as radiated S-wave energy, (ES), from waveforms recorded by as few as one station, for events that were too small to be waveform modelled (i.e. events less than MW~ 3.5); (ii) the source spectra were used to derive an equivalent local magnitude, ML(coda), that is in excellent agreement with the network averaged values using direct S waves; (iii) scaled energy, , where ER, the radiated seismic energy, is comparable to results from other tectonically active regions (e.g. western USA, Japan) and supports the idea that there is a fundamental

  9. On the relative magnitudes of photosynthesis, respiration, growth and carbon storage in vegetation

    Science.gov (United States)

    van Oijen, M.

    2012-04-01

    • Background and Aims. The carbon balance of vegetation is dominated by the two large fluxes of photosynthesis (P) and respiration (R). Mechanistic models have attempted to simulate the two fluxes separately, each with their own set of internal and external controls. This has led to model predictions where environmental change causes R to exceed P, with consequent dieback of vegetation. However, empirical evidence suggests that the R:P ratio is constrained to a narrow range of about 0.4-0.5. Physiological explanations for the narrow range are not conclusive. We aim to introduce a novel perspective by theoretical study of the quantitative relationship between the four carbon fluxes of P, R, growth and storage (or its inverse, remobilisation). • Methods. Starting from the law of conservation of mass - in this case carbon - we derive equations for the relative magnitudes of all carbon fluxes which depend on only two parameters: the R:P ratio and the relative rate of storage of carbon into remobilisable reserves. The equations are used to explain observed flux ratios and to analyse incomplete data sets of carbon fluxes. • Key Results. Storage rate is shown to be a freely varying parameter, whereas R:P is narrowly constrained. This explains the constancy of the ratio reported in the literature. With the information thus gained, a data set of R and P in grassland was analysed, and flux estimates could be derived for the periods after cuts in which plant growth is dominated by remobilisation before photosynthesis takes over. • Conclusions. We conclude that the relative magnitudes of photosynthesis, respiration, growth and substrate storage are indeed tightly constrained, but because of mass conservation rather than for physiological reasons. This facilitates analysis of incomplete data sets. Mechanistic models, as the embodiment of physiological mechanisms, need to show consistency with the constraints. • Reference. Van Oijen, M., Schapendonk, A. & Höglind, M

  10. Estimating flexural rigidity and load magnitude required for formation of Ross Island flexure moat

    Science.gov (United States)

    Jha, S.; Harry, D. L.; Wenman, C. P.

    2017-12-01

    rigidity estimate of 6.9 x 1019 Nm. The load magnitudes determined from these flexure models lie in the range of 4.6 x 1015 N - 4.3 x 1016 N. This is less than the topographic load (6.9 x 1017 N estimated from BEDMAP2) produced by the island by one to two orders of magnitude. The difference in load magnitudes suggest anomalously low densities caused by high lower crust and mantle temperatures in the region.

  11. Influence of strength on magnitude and mechanisms of adaptation to power training.

    Science.gov (United States)

    Cormie, Prue; McGuigan, Michael R; Newton, Robert U

    2010-08-01

    To determine whether the magnitude of performance improvements and the mechanisms driving adaptation to ballistic power training differ between strong and weak individuals. Twenty-four men were divided into three groups on the basis of their strength level: stronger (n = 8, one-repetition maximum-to-body mass ratio (1RM/BM) = 1.97 +/- 0.08), weaker (n = 8, 1RM/BM = 1.32 +/- 0.14), or control (n = 8, 1RM/BM = 1.37 +/- 0.13). The stronger and weaker groups trained three times per week for 10 wk. During these sessions, subjects performed maximal-effort jump squats with 0%-30% 1RM. The impact of training on athletic performance was assessed using a 2-d testing battery that involved evaluation of jump and sprint performance as well as measures of the force-velocity relationship, jumping mechanics, muscle architecture, and neural drive. Both experimental groups showed significant (P < or = 0.05) improvements in jump (stronger: peak power = 10.0 +/- 5.2 W.kg, jump height = 0.07 +/- 0.04 m; weaker: peak power = 9.1 +/- 2.3 W.kg, jump height = 0.06 +/- 0.04 m) and sprint performance after training (stronger: 40-m time = -2.2% +/- 2.0%; weaker: 40-m time = -3.6% +/- 2.3%). Effect size analyses revealed a tendency toward practically relevant differences existing between stronger and weaker individuals in the magnitude of improvements in jump performance (effect size: stronger: peak power = 1.55, jump height = 1.46; weaker: peak power = 1.03, jump height = 0.95) and especially after 5 wk of training (effect size: stronger: peak power = 1.60, jump height = 1.59; weaker: peak power = 0.95, jump height = 0.61). The mechanisms driving these improvements included significant (P < or = 0.05) changes in the force-velocity relationship, jump mechanics, and neural activation, with no changes to muscle architecture observed. The magnitude of improvements after ballistic power training was not significantly influenced by strength level. However, the training had a tendency toward

  12. Consolidation of an extinction memory depends on the unconditioned stimulus magnitude previously experienced during training.

    Science.gov (United States)

    Stollhoff, Nicola; Eisenhardt, Dorothea

    2009-07-29

    Here, we examine the role of the magnitude of the unconditioned stimulus (US) during classical conditioning in consolidation processes after memory retrieval. We varied the US durations during training and we test the impact of these variations on consolidation after memory retrieval with one or two conditioned stimulus-only trials. We found that the consolidation of an extinction memory depends on US duration during training and ruled out the possibility that this effect is attributable to differences in satiation after conditioning. We conclude that consolidation of an extinction memory is triggered only when the duration of the US reaches a critical threshold. This demonstrates that memory consolidation cannot be regarded as an isolated process depending solely on training conditions. Instead, it depends on the animal's previous experience as well.

  13. On the magnitude and distribution of halo currents during disruptions on MAST

    International Nuclear Information System (INIS)

    Counsell, G F; Martin, R; Pinfold, T; Taylor, D

    2007-01-01

    Recent results from MAST in which all halo current paths are monitored suggest that, during disruptions, the plasma responsible for the generation of halo current acts more as a voltage source than a current source. As a result the resistance of the current path along which the halo current must flow has a profound impact on the magnitude of the current. This may provide opportunities for directing the current away from sensitive components in future devices such as ITER. Analysis of data from over 3800 disruptions shows that the halo currents on MAST are relatively benign, having a peak value less than 25% of the pre-disruption plasma current with a rather symmetric distribution near the centre column (average toroidal peaking factor ∼1.1). The low peaking factor favourably reduces the tilting/bending forces in the region of the centre column, which has limited space for bulky supports

  14. Iris Segmentation using Gradient Magnitude and Fourier Descriptor for Multimodal Biometric Authentication System

    Directory of Open Access Journals (Sweden)

    Defiana Sulaeman

    2016-12-01

    Full Text Available Perfectly segmenting the area of the iris is one of the most important steps in iris recognition. There are several problematic areas that affect the accuracy of the iris segmentation step, such as eyelids, eyelashes, glasses, pupil (due to less accurate iris segmentation, motion blur, and lighting and specular reflections. To solve these problems, gradient magnitude and Fourier descriptor are employed to do iris segmentation in the proposed Multimodal Biometric Authentication System (MBAS. This approach showed quite promising results, i.e. an accuracy rate of 97%. The result of the iris recognition system was combined with the result of an open-source fingerprint recognition system to develop a multimodal biometrics authentication system. The results of the fusion between iris and fingerprint authentication were 99% accurate. Data from Multimedia Malaysia University (MMUI and our own prepared database, the SGU-MB-1 dataset, were used to test the accuracy of the proposed system.

  15. Olive oil increases the magnitude of postprandial chylomicron remnants compared to milk fat and safflower oil.

    Science.gov (United States)

    Higashi, K; Ishikawa, T; Shige, H; Tomiyasu, K; Yoshida, H; Ito, T; Nakajima, K; Yonemura, A; Sawada, S; Nakamura, H

    1997-10-01

    The acute effects of olive oil, milk fat and safflower oil on postprandial lipemia and remnant lipoprotein metabolism were investigated. Eight Healthy male volunteers randomly underwent three types of oral fat-vitamin A loading tests. The test drink was a mixture of retinyl palmitate (RP)(50,000 IU of aqueous vitamin A/m2 body surface area) and one of the three types of oils (40 g of fat/m2 body surface area): olive oil (70.7% oleic acid of total fatty acids); milk fat (69.3% saturated fatty acid); safflower oil (74.2% linoleic acid). Olive oil significantly increased plasma triacylglycerol and RP concentrations 4 hours after fat loading, as compared to other fats. Increases of remnant like particle concentrations were higher after olive oil than after the other two fats. These results show that olive oil increases the magnitude of postprandial chylomicrons and chylomicron remnants compared to milk fat and safflower oil.

  16. Scaling relation between earthquake magnitude and the departure time from P wave similar growth

    Science.gov (United States)

    Noda, Shunta; Ellsworth, William L.

    2016-01-01

    We introduce a new scaling relation between earthquake magnitude (M) and a characteristic of initial P wave displacement. By examining Japanese K-NET data averaged in bins partitioned by Mw and hypocentral distance, we demonstrate that the P wave displacement briefly displays similar growth at the onset of rupture and that the departure time (Tdp), which is defined as the time of departure from similarity of the absolute displacement after applying a band-pass filter, correlates with the final M in a range of 4.5 ≤ Mw ≤ 7. The scaling relation between Mw and Tdp implies that useful information on the final M can be derived while the event is still in progress because Tdp occurs before the completion of rupture. We conclude that the scaling relation is important not only for earthquake early warning but also for the source physics of earthquakes.

  17. A New High Frequency Injection Method Based on Duty Cycle Shifting without Maximum Voltage Magnitude Loss

    DEFF Research Database (Denmark)

    Wang, Dong; Lu, Kaiyuan; Rasmussen, Peter Omand

    2015-01-01

    The conventional high frequency signal injection method is to superimpose a high frequency voltage signal to the commanded stator voltage before space vector modulation. Therefore, the magnitude of the voltage used for machine torque production is limited. In this paper, a new high frequency...... amplitude. This may be utilized to develop new position estimation algorithm without involving the inductance in the medium to high speed range. As an application example, a developed inductance independent position estimation algorithm using the proposed high frequency injection method is applied to drive...... injection method, in which high frequency signal is generated by shifting the duty cycle between two neighboring switching periods, is proposed. This method allows injecting a high frequency signal at half of the switching frequency without the necessity to sacrifice the machine fundamental voltage...

  18. On the Magnitude of the Nonadiabatic Error for Highly Coupled Radicals

    Science.gov (United States)

    Stanton, J. F.

    2009-06-01

    A review is given of recent advances in the construction of (quasi)diabatic model Hamiltonians and their application to analyzing the spectroscopy of molecules with strong vibronic coupling. A numerical application to the vibronic levels of the BNB radical below 0.6 eV is presented, together with corresponding adiabatic (quantum chemistry) calculations. The agreement with the experimental levels is nearly quantitative with the model Hamiltonian, attesting to the power of the approach. On the contrary, it is also revealed that the magnitude of the nonadiabatic contributions to the zero-point energy and the lowest fundamental frequency of the coupling mode are considerably larger than expected, at least by your narrator.

  19. Positive and negative gain exceeding unity magnitude in silicon quantum well metal-oxide-semiconductor transistors

    Science.gov (United States)

    Hu, Gangyi; Wijesinghe, Udumbara; Naquin, Clint; Maggio, Ken; Edwards, H. L.; Lee, Mark

    2017-10-01

    Intrinsic gain (AV) measurements on Si quantum well (QW) n-channel metal-oxide-semiconductor (NMOS) transistors show that these devices can have |AV| > 1 in quantum transport negative transconductance (NTC) operation at room temperature. QW NMOS devices were fabricated using an industrial 45 nm technology node process incorporating ion implanted potential barriers to define a lateral QW in the conduction channel under the gate. While NTC at room temperature arising from transport through gate-controlled QW bound states has been previously established, it was unknown whether the quantum NTC mechanism could support gain magnitude exceeding unity. Bias conditions were found giving both positive and negative AV with |AV| > 1 at room temperature. This result means that QW NMOS devices could be useful in amplifier and oscillator applications.

  20. Absolute magnitude estimation and relative judgement approaches to subjective workload assessment

    Science.gov (United States)

    Vidulich, Michael A.; Tsang, Pamela S.

    1987-01-01

    Two rating scale techniques employing an absolute magnitude estimation method, were compared to a relative judgment method for assessing subjective workload. One of the absolute estimation techniques used was an unidimensional overall workload scale and the other was the multidimensional NASA-Task Load Index technique. Thomas Saaty's Analytic Hierarchy Process was the unidimensional relative judgment method used. These techniques were used to assess the subjective workload of various single- and dual-tracking conditions. The validity of the techniques was defined as their ability to detect the same phenomena observed in the tracking performance. Reliability was assessed by calculating test-retest correlations. Within the context of the experiment, the Saaty Analytic Hierarchy Process was found to be superior in validity and reliability. These findings suggest that the relative judgment method would be an effective addition to the currently available subjective workload assessment techniques.

  1. Associations Between Magnitude of Child Maltreatment and Medicaid Expenditures for Psychotropic Medications.

    Science.gov (United States)

    Raghavan, Ramesh; Brown, Derek S; Allaire, Benjamin T; Ross, Raven E; Landsverk, John

    2016-08-01

    This study examined relationships between various measures of the severity of child maltreatment and expenditures on psychotropic drugs among children in the welfare system. Child participants (N=4,453) in the first National Survey of Child and Adolescent Well-Being (NSCAW) were linked to their Medicaid claims from 36 states. Three specifications for severity of maltreatment were developed. A two-part regression of logistic and generalized linear models of expenditures on psychotropic medications was estimated for each specification. Physically abused children had higher odds (odds ratio [OR]=1.34) and neglected children had lower odds (OR=.76) of incurring psychotropic drug expenditures. Children who experienced the most severe level of harm had higher odds (OR=1.33) of medication use, compared with children without appreciable harm. No maltreatment specifications were associated with increased expenditures on psychotropic drugs. The magnitude of maltreatment affected odds of use of psychotropic drugs but had no effect on Medicaid expenditures for these drugs.

  2. Earthquake recurrence and magnitude and seismic deformation of the northwestern Okhotsk plate, northeast Russia

    Science.gov (United States)

    Hindle, D.; Mackey, K.

    2011-02-01

    Recorded seismicity from the northwestern Okhotsk plate, northeast Asia, is currently insufficient to account for the predicted slip rates along its boundaries due to plate tectonics. However, the magnitude-frequency relationship for earthquakes from the region suggests that larger earthquakes are possible in the future and that events of ˜Mw 7.5 which should occur every ˜100-350 years would account for almost all the slip of the plate along its boundaries due to Eurasia-North America convergence. We use models for seismic slip distribution along the bounding faults of Okhotsk to conclude that relatively little aseismic strain release is occurring and that larger future earthquakes are likely in the region. Our models broadly support the idea of a single Okhotsk plate, with the large majority of tectonic strain released along its boundaries.

  3. Experimental analysis of physical magnitudes through films and its application in the classroom

    Directory of Open Access Journals (Sweden)

    Ezquerra Martínez, Ángel;

    2012-04-01

    Full Text Available In this paper we show how our Secondary and High School students have been able to research phenomena or physical situation of their real lives closer to their interests in the last 10 years. The procedure is to make digital video recordings and then applying a computer program (Avimèca, which monitors the scene frame by frame and attaching numerical values to each selected point in order to analyze some physical magnitudes. Contrary to what may seem, the procedure is simple and relatively inexpensive elements are used. In any case, to make it easier for other teachers, a program guide is added which is free-access. In addition, the way in which we implemented this classroom activity is detailed, listing the difficulties encountered and the corresponding proposed solutions.

  4. Adaptive Command Filtered Integrated Guidance and Control for Hypersonic Vehicle with Magnitude, Rate and Bandwidth Constraints

    Directory of Open Access Journals (Sweden)

    Wang Liang

    2018-01-01

    Full Text Available This paper proposes a novel integrated guidance and control (IGC method for hypersonic vehicle in terminal phase. Firstly, the system model is developed with a second order actuator dynamics. Then the back-stepping controller is designed hierarchically with command filters, where the first order command filters are implemented to construct the virtual control input with ideal states predicted by an adaptive estimator, and the nonlinear command filter is designed to produce magnitude, rate and bandwidth limited control surface deflection finally tracked by a terminal sliding mode controller with finite convergence time. Through a series of 6-DOF numerical simulations, it’s indicated that the proposed method successfully cancels out the large aerodynamics coefficient uncertainties and disturbances in hypersonic flight under limited control surface deflection. The contribution of this paper lies in the application and determination of nonlinear integrated design of guidance and control system for hypersonic vehicle.

  5. Process criticality accident likelihoods, magnitudes and emergency planning. A focus on solution accidents

    International Nuclear Information System (INIS)

    McLaughlin, Thomas P.

    2003-01-01

    This paper presents analyses and applications of data from reactor and critical experiment research on the dynamics of nuclear excursions in solution media. Available criticality accident information is also discussed and shown to provide strong evidence of the overwhelming likelihood of accidents in liquid media over other forms and to support the measured data. These analyses are shown to provide valuable insights into key parameters important to understanding solution excursion dynamics in general and in evaluating practical upper bounds on criticality accident magnitudes. This understanding and these upper bounds are directly applicable to the evaluation of the consequences of postulated criticality accidents. These bounds are also essential in order to comply with national and international consensus standards and regulatory requirements for emergency planning. (author)

  6. Magnitude, moment, and measurement: The seismic mechanism controversy and its resolution.

    Science.gov (United States)

    Miyake, Teru

    This paper examines the history of two related problems concerning earthquakes, and the way in which a theoretical advance was involved in their resolution. The first problem is the development of a physical, as opposed to empirical, scale for measuring the size of earthquakes. The second problem is that of understanding what happens at the source of an earthquake. There was a controversy about what the proper model for the seismic source mechanism is, which was finally resolved through advances in the theory of elastic dislocations. These two problems are linked, because the development of a physically-based magnitude scale requires an understanding of what goes on at the seismic source. I will show how the theoretical advances allowed seismologists to re-frame the questions they were trying to answer, so that the data they gathered could be brought to bear on the problem of seismic sources in new ways. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Effect of slip-area scaling on the earthquake frequency-magnitude relationship

    Science.gov (United States)

    Senatorski, Piotr

    2017-06-01

    The earthquake frequency-magnitude relationship is considered in the maximum entropy principle (MEP) perspective. The MEP suggests sampling with constraints as a simple stochastic model of seismicity. The model is based on the von Neumann's acceptance-rejection method, with b-value as the parameter that breaks symmetry between small and large earthquakes. The Gutenberg-Richter law's b-value forms a link between earthquake statistics and physics. Dependence between b-value and the rupture area vs. slip scaling exponent is derived. The relationship enables us to explain observed ranges of b-values for different types of earthquakes. Specifically, different b-value ranges for tectonic and induced, hydraulic fracturing seismicity is explained in terms of their different triggering mechanisms: by the applied stress increase and fault strength reduction, respectively.

  8. Magnitudes and units in the X-ray dosimetry in diagnostic radiology

    International Nuclear Information System (INIS)

    Tovar M, V. M.; Cejudo A, J.; Vergara M, F.

    2009-10-01

    The dosimetry objective in the radiological image is the quantification from the exposition to the radiation with a commitment of optimizing the image quality to the reason of the absorbed dose. The dosimetry has the meaning of avoiding excessive dose that could imply a significant risk of deterministic effects induction. The dosimetric magnitudes and dosimetry protocols in the radiological image, are those that are related to the risks for the patient. Exist in diagnostic radiology two fundamentals reason to measure or to estimate the patient radiation dose. First, the mensurations are a means to verify the good practices and an aid to the optimization of the patient protection. Second, the absorbed dose estimation to tissues and organs in the patient are necessary to determine the risks, and this way to indicate that the radiological techniques employees can be justified and in investigated cases of over exposition. (Author)

  9. A statistical study of magnetic field magnitude changes during substorms in the near earth tail

    Science.gov (United States)

    Lopez, R. E.; Lui, A. T. Y.; Mcentire, R. W.; Potemra, T. A.; Krimigis, S. M.

    1990-01-01

    Using AMPTE/CCE data taken in 1985 and 1986 when the CCE apogee (8.8 earth radii) was within 4.5 hours of midnight, 167 injection events in the near-earth magnetotail have been cataloged. These events are exactly or nearly dispersionless on a 72-sec time scale from 25 keV to 285 keV. The changes in the field magnitude are found to be consistent with the expected effects of the diversion/disruption of the cross-tail current during a substorm, and the latitudinal position of the current sheet is highly variable within the orbit of CCE. The local time variation of the magnetic-field changes implies that the substorm current wedge is composed of longitudinally broad Birkeland currents.

  10. Magnitude of the Current in Two-Dimensional Interlayer Tunneling Devices.

    Science.gov (United States)

    Feenstra, Randall; de la Barrera, Sergio; Li, Jun; Nie, Yifan; Cho, Kyeongjae

    2018-01-02

    Using the Bardeen tunneling method with first-principles wave functions, computations are made of the tunneling current in graphene / hexagonal-boron-nitride / graphene (G/h-BN/G) vertical structures. Detailed comparison with prior experimental results is made, focusing on the magnitude of the achievable tunnel current. With inclusion of the effects of translational and rotational misalignment of the graphene and the h-BN, predicted currents are found to be about 15x larger than experimental values. A reduction in this discrepancy, to a factor of 2.5x, is achieved by utilizing a realistic size for the band gap of the h-BN, hence affecting the exponential decay constant for the tunneling. © 2018 IOP Publishing Ltd.

  11. Source terms: an investigation of uncertainties, magnitudes, and recommendations for research. [PWR; BWR

    Energy Technology Data Exchange (ETDEWEB)

    Levine, S.; Kaiser, G. D.; Arcieri, W. C.; Firstenberg, H.; Fulford, P. J.; Lam, P. S.; Ritzman, R. L.; Schmidt, E. R.

    1982-03-01

    The purpose of this document is to assess the state of knowledge and expert opinions that exist about fission product source terms from potential nuclear power plant accidents. This is so that recommendations can be made for research and analyses which have the potential to reduce the uncertainties in these estimated source terms and to derive improved methods for predicting their magnitudes. The main reasons for writing this report are to indicate the major uncertainties involved in defining realistic source terms that could arise from severe reactor accidents, to determine which factors would have the most significant impact on public risks and emergency planning, and to suggest research and analyses that could result in the reduction of these uncertainties. Source terms used in the conventional consequence calculations in the licensing process are not explicitly addressed.

  12. Simulation model structure numerically robust to changes in magnitude and combination of input and output variables

    DEFF Research Database (Denmark)

    Rasmussen, Bjarne D.; Jakobsen, Arne

    1999-01-01

    Mathematical models of refrigeration systems are often based on a coupling of component models forming a “closed loop” type of system model. In these models the coupling structure of the component models represents the actual flow path of refrigerant in the system. Very often numerical...... instabilities prevent the practical use of such a system model for more than one input/output combination and for other magnitudes of refrigerating capacities.A higher numerical robustness of system models can be achieved by making a model for the refrigeration cycle the core of the system model and by using...... variables with narrow definition intervals for the exchange of information between the cycle model and the component models.The advantages of the cycle-oriented method are illustrated by an example showing the refrigeration cycle similarities between two very different refrigeration systems....

  13. The Role and Magnitude of Order Flows in Seoul Foreign Market

    Directory of Open Access Journals (Sweden)

    Chae-Shick Chung

    2010-06-01

    Full Text Available In this paper, we test the role of order flows in KRW/USD. We use transaction based high frequency data (electronic broker happened in 2006. For robustness check, we extend our analysis by combining exchange rates (indicative quotes v.s. transaction rate, frequency (transaction based time v.s. 1 minute through 1 day, and order flows (sign v.s. signed volume. The results show that order flow is an important variable for explaining the KRW/USD regardless of frequency and of choice of quotes. Based on Hasbrouck's measure we find that 14-28% of permanent exchange rate variation is due to private information. The magnitude is smaller than that of international currency presenting, for example, in Payne (2003. The discrepancy arises both from currency choice and from too short data span in Payne (2003.

  14. Colour-magnitude diagrams of star clusters in the Magellanic Clouds from wide-field electronography

    International Nuclear Information System (INIS)

    Andersen, J.; Walker, M.F.

    1984-01-01

    Utilizing the good image quality and large field available with the 9-cm McMullan electronographic camera when attached to the Danish 1.54-m Ritchey-Chretien reflector at La Silla, Chile, a number of star clusters in the Magellanic Clouds have been observed in order to determine their colour-magnitude diagrams with proper correction for the field star contribution. In Hodge 11, the first cluster to be reported from this programme, good measurements have been obtained of 180 stars in the annular field 34 <= R <= 71 arcsec of the cluster itself, and of 154 stars in a nearby control field of similar area, to a limit of V of the order of 22. (author)

  15. The magnitude of linear dichroism of biological tissues as a result of cancer changes

    Science.gov (United States)

    Bojchuk, T. M.; Yermolenko, S. B.; Fedonyuk, L. Y.; Petryshen, O. I.; Guminetsky, S. G.; Prydij, O. G.

    2011-09-01

    The results of studies of linear dichroism values of different types of biological tissues (human prostate, esophageal epithelial human muscle tissue in rats) both healthy and infected tumor at different stages of development are shown here. The significant differences in magnitude of linear dichroism and its spectral dependence in the spectral range λ = 330 - 750 nm both among the objects of study, and between biotissues: healthy (or affected by benign tumors) and cancer patients are established. It is researched that in all cases in biological tissues (prostate gland, esophagus, human muscle tissue in rats) with cancer the linear dichroism arises, the value of which depends on the type of tissue and time of the tumor process. As for healthy tissues linear dichroism is absent, the results may have diagnostic value for detecting and assessing the degree of development of cancer.

  16. Poststroke Hemiparesis Impairs the Rate but not Magnitude of Adaptation of Spatial and Temporal Locomotor Features

    Science.gov (United States)

    Savin, Douglas N.; Tseng, Shih-Chiao; Whitall, Jill; Morton, Susanne M.

    2015-01-01

    Background Persons with stroke and hemiparesis walk with a characteristic pattern of spatial and temporal asymmetry that is resistant to most traditional interventions. It was recently shown in nondisabled persons that the degree of walking symmetry can be readily altered via locomotor adaptation. However, it is unclear whether stroke-related brain damage affects the ability to adapt spatial or temporal gait symmetry. Objective Determine whether locomotor adaptation to a novel swing phase perturbation is impaired in persons with chronic stroke and hemiparesis. Methods Participants with ischemic stroke (14) and nondisabled controls (12) walked on a treadmill before, during, and after adaptation to a unilateral perturbing weight that resisted forward leg movement. Leg kinematics were measured bilaterally, including step length and single-limb support (SLS) time symmetry, limb angle center of oscillation, and interlimb phasing, and magnitude of “initial” and “late” locomotor adaptation rates were determined. Results All participants had similar magnitudes of adaptation and similar initial adaptation rates both spatially and temporally. All 14 participants with stroke and baseline asymmetry temporarily walked with improved SLS time symmetry after adaptation. However, late adaptation rates poststroke were decreased (took more strides to achieve adaptation) compared with controls. Conclusions Mild to moderate hemiparesis does not interfere with the initial acquisition of novel symmetrical gait patterns in both the spatial and temporal domains, though it does disrupt the rate at which “late” adaptive changes are produced. Impairment of the late, slow phase of learning may be an important rehabilitation consideration in this patient population. PMID:22367915

  17. Magnitude and correlates of bird collisions at glass bus shelters in an urban landscape.

    Science.gov (United States)

    Barton, Christine M; Riding, Corey S; Loss, Scott R

    2017-01-01

    Wildlife residing in urban landscapes face many human-related threats to their survival. For birds, collision with glass on manmade structures has been identified as a major hazard, causing hundreds of millions of avian fatalities in North America every year. Although research has investigated factors associated with bird-glass collision mortality at buildings, no prior studies have focused on bird fatalities at glass-walled bus shelters. Our objectives in this study were to describe the magnitude of bird-bus shelter collisions in the city of Stillwater, Oklahoma and assess potential predictors of collision risk, including characteristics of shelters (glass area) and surrounding land cover (e.g., vegetative features). We surveyed for bird carcasses and indirect collision evidence at 18 bus shelters over a five-month period. Linear regression and model selection results revealed that the amount of glass on shelters and the area of lawn within 50 m of shelters were both positively related to fatal bird collisions; glass area was also positively associated with observations of collision evidence on glass surfaces. After accounting for scavenger removal of carcasses, we estimate that a minimum of 34 birds are killed each year between May and September by collision with the 36 bus shelters in the city of Stillwater. While our study provides an initial look at bird fatalities at bus shelters, additional research is needed to generate a large-scale estimate of collision mortality and to assess species composition of fatalities at a national scale. Designing new bus shelters to include less glass and retrofitting existing shelters to increase visibility of glass to birds will likely reduce fatal bird collisions at bus shelters and thus reduce the cumulative magnitude of anthropogenic impacts to birds in cities.

  18. Correlation between Ribosome Biogenesis and the Magnitude of Hypertrophy in Overloaded Skeletal Muscle.

    Science.gov (United States)

    Nakada, Satoshi; Ogasawara, Riki; Kawada, Shigeo; Maekawa, Takahiro; Ishii, Naokata

    2016-01-01

    External loads applied to skeletal muscle cause increases in the protein translation rate, which leads to muscle hypertrophy. Although some studies have demonstrated that increases in the capacity and efficiency of translation are involved in this process, it remains unclear how these two factors are related to the magnitude of muscle hypertrophy. The present study aimed to clarify the roles played by the capacity and efficiency of translation in muscle hypertrophy. We used an improved synergist ablation in which the magnitude of compensatory hypertrophy could be controlled by partial removal of synergist muscles. Male rats were assigned to four groups in which the plantaris muscle was unilaterally subjected to weak (WK), moderate (MO), middle (MI), and strong (ST) overloading by four types of synergist ablation. Fourteen days after surgery, the weight of the plantaris muscle per body weight increased by 8%, 22%, 32% and 45%, in the WK, MO, MI and ST groups, respectively. Five days after surgery, 18+28S rRNA content (an indicator of translational capacity) increased with increasing overload, with increases of 1.8-fold (MO), 2.2-fold (MI), and 2.5-fold (ST), respectively, relative to non-overloaded muscle (NL) in the WK group. rRNA content showed a strong correlation with relative muscle weight measured 14 days after surgery (r = 0.98). The phosphorylated form of p70S6K (a positive regulator of translational efficiency) showed a marked increase in the MO group, but no further increase was observed with further increase in overload (increases of 22.6-fold (MO), 17.4-fold (MI), and 18.2-fold (ST), respectively, relative to NL in the WK group). These results indicate that increases in ribosome biogenesis at the early phase of overloading are strongly dependent on the amount of overloading, and may play an important role in increasing the translational capacity for further gain of muscular size.

  19. A unified classification of alien species based on the magnitude of their environmental impacts.

    Directory of Open Access Journals (Sweden)

    Tim M Blackburn

    2014-05-01

    Full Text Available Species moved by human activities beyond the limits of their native geographic ranges into areas in which they do not naturally occur (termed aliens can cause a broad range of significant changes to recipient ecosystems; however, their impacts vary greatly across species and the ecosystems into which they are introduced. There is therefore a critical need for a standardised method to evaluate, compare, and eventually predict the magnitudes of these different impacts. Here, we propose a straightforward system for classifying alien species according to the magnitude of their environmental impacts, based on the mechanisms of impact used to code species in the International Union for Conservation of Nature (IUCN Global Invasive Species Database, which are presented here for the first time. The classification system uses five semi-quantitative scenarios describing impacts under each mechanism to assign species to different levels of impact-ranging from Minimal to Massive-with assignment corresponding to the highest level of deleterious impact associated with any of the mechanisms. The scheme also includes categories for species that are Not Evaluated, have No Alien Population, or are Data Deficient, and a method for assigning uncertainty to all the classifications. We show how this classification system is applicable at different levels of ecological complexity and different spatial and temporal scales, and embraces existing impact metrics. In fact, the scheme is analogous to the already widely adopted and accepted Red List approach to categorising extinction risk, and so could conceivably be readily integrated with existing practices and policies in many regions.

  20. Historical precipitation predictably alters the shape and magnitude of microbial functional response to soil moisture.

    Science.gov (United States)

    Averill, Colin; Waring, Bonnie G; Hawkes, Christine V

    2016-05-01

    Soil moisture constrains the activity of decomposer soil microorganisms, and in turn the rate at which soil carbon returns to the atmosphere. While increases in soil moisture are generally associated with increased microbial activity, historical climate may constrain current microbial responses to moisture. However, it is not known if variation in the shape and magnitude of microbial functional responses to soil moisture can be predicted from historical climate at regional scales. To address this problem, we measured soil enzyme activity at 12 sites across a broad climate gradient spanning 442-887 mm mean annual precipitation. Measurements were made eight times over 21 months to maximize sampling during different moisture conditions. We then fit saturating functions of enzyme activity to soil moisture and extracted half saturation and maximum activity parameter values from model fits. We found that 50% of the variation in maximum activity parameters across sites could be predicted by 30-year mean annual precipitation, an indicator of historical climate, and that the effect is independent of variation in temperature, soil texture, or soil carbon concentration. Based on this finding, we suggest that variation in the shape and magnitude of soil microbial response to soil moisture due to historical climate may be remarkably predictable at regional scales, and this approach may extend to other systems. If historical contingencies on microbial activities prove to be persistent in the face of environmental change, this approach also provides a framework for incorporating historical climate effects into biogeochemical models simulating future global change scenarios. © 2016 John Wiley & Sons Ltd.

  1. The magnitude of translational and rotational head accelerations experienced by riders during downhill mountain biking.

    Science.gov (United States)

    Hurst, Howard T; Atkins, Stephen; Dickinson, Ben D

    2018-03-21

    To determine the magnitude of translational and rotational head accelerations during downhill mountain biking. Observational study. Sixteen male downhill cyclists (age 26.4±8.4years; stature 179.4±7.2cm; mass 75.3±5.9kg) were monitored during two rounds of the British Downhill Series. Riders performed two runs on each course wearing a triaxial accelerometer behind the right ear. The means of the two runs for each course were used to determine differences between courses for mean and maximum peak translational (g) and rotational accelerations (rad/s 2 ) and impact duration for each course. Significant differences (p10g), FW=12.5±7.6, RYF=42.8±27.4 (t (22.96) =-4.70; p<0.001; 95% CI=17.00 to 43.64); maximum peak rotational acceleration, FW=6805.4±3073.8rad/s 2 , RYF=9799.9±3381.7rad/s 2 (t (32) =-2.636; p=0.01; 95% CI=680.31 to 5308.38); mean acceleration duration FW=4.7±1.2ms, RYF=6.5±1.4ms (t (32) =-4.05; p<0.001; 95% CI=0.91 to 2.76) and maximum acceleration duration, FW=11.6±4.5ms, RYF=21.2±9.1 (t (29.51) =-4.06; p=0.001; 95% CI=4.21 to 14.94). No other significant differences were found. Findings indicate that downhill riders may be at risk of sustaining traumatic brain injuries and course design influences the number and magnitude of accelerations. Copyright © 2018 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  2. On the relative magnitudes of photosynthesis, respiration, growth and carbon storage in vegetation.

    Science.gov (United States)

    Van Oijen, Marcel; Schapendonk, Ad; Höglind, Mats

    2010-05-01

    The carbon balance of vegetation is dominated by the two large fluxes of photosynthesis (P) and respiration (R). Mechanistic models have attempted to simulate the two fluxes separately, each with their own set of internal and external controls. This has led to model predictions where environmental change causes R to exceed P, with consequent dieback of vegetation. However, empirical evidence suggests that the R : P ratio is constrained to a narrow range of about 0.4-0.5. Physiological explanations for the narrow range are not conclusive. The aim of this work is to introduce a novel perspective by theoretical study of the quantitative relationship between the four carbon fluxes of P, R, growth and storage (or its inverse, remobilization). Starting from the law of conservation of mass - in this case carbon - equations are derived for the relative magnitudes of all carbon fluxes, which depend on only two parameters: the R : P ratio and the relative rate of storage of carbon in remobilizable reserves. The equations are used to explain observed flux ratios and to analyse incomplete data sets of carbon fluxes. The storage rate is shown to be a freely varying parameter, whereas R : P is narrowly constrained. This explains the constancy of the ratio reported in the literature. With the information thus gained, a data set of R and P in grassland was analysed, and flux estimates could be derived for the periods after cuts in which plant growth is dominated by remobilization before photosynthesis takes over. It is concluded that the relative magnitudes of photosynthesis, respiration, growth and substrate storage are indeed tightly constrained, but because of mass conservation rather than for physiological reasons. This facilitates analysis of incomplete data sets. Mechanistic models, as the embodiment of physiological mechanisms, need to show consistency with the constraints.

  3. Correlation between Ribosome Biogenesis and the Magnitude of Hypertrophy in Overloaded Skeletal Muscle.

    Directory of Open Access Journals (Sweden)

    Satoshi Nakada

    Full Text Available External loads applied to skeletal muscle cause increases in the protein translation rate, which leads to muscle hypertrophy. Although some studies have demonstrated that increases in the capacity and efficiency of translation are involved in this process, it remains unclear how these two factors are related to the magnitude of muscle hypertrophy. The present study aimed to clarify the roles played by the capacity and efficiency of translation in muscle hypertrophy. We used an improved synergist ablation in which the magnitude of compensatory hypertrophy could be controlled by partial removal of synergist muscles. Male rats were assigned to four groups in which the plantaris muscle was unilaterally subjected to weak (WK, moderate (MO, middle (MI, and strong (ST overloading by four types of synergist ablation. Fourteen days after surgery, the weight of the plantaris muscle per body weight increased by 8%, 22%, 32% and 45%, in the WK, MO, MI and ST groups, respectively. Five days after surgery, 18+28S rRNA content (an indicator of translational capacity increased with increasing overload, with increases of 1.8-fold (MO, 2.2-fold (MI, and 2.5-fold (ST, respectively, relative to non-overloaded muscle (NL in the WK group. rRNA content showed a strong correlation with relative muscle weight measured 14 days after surgery (r = 0.98. The phosphorylated form of p70S6K (a positive regulator of translational efficiency showed a marked increase in the MO group, but no further increase was observed with further increase in overload (increases of 22.6-fold (MO, 17.4-fold (MI, and 18.2-fold (ST, respectively, relative to NL in the WK group. These results indicate that increases in ribosome biogenesis at the early phase of overloading are strongly dependent on the amount of overloading, and may play an important role in increasing the translational capacity for further gain of muscular size.

  4. The Distribution and Magnitude of Glacial Erosion on 103-year Timescales at Engabreen, Norway

    Science.gov (United States)

    Rand, C.; Goehring, B. M.

    2017-12-01

    We derive the magnitudes of glacial erosion integrated over 103-year timescales across a transect transverse to the direction of ice flow at Engabreen, Norway. Understanding the distribution of glacial erosion is important for several reasons, including sediment budgeting to fjord environments, development of robust landscape evolution models, and if a better understanding between erosion and ice-bed interface properties (e.g., sliding rate, basal water pressure) can be developed, we can use records of glacial erosion to infer glaciological properties that can ultimately benefit models of past and future glaciers. With few exceptions, measurements of glacial erosion are limited to the historical past and even then are rare owing to the difficulty of accessing the glacier bed. One method proven useful in estimating glacial erosion on 103-year timescales is to measure the remaining concentrations of cosmogenic nuclides that accumulate in exposed bedrock during periods of retracted glacier extent and are removed by glacial erosion and radioactive decay during ice cover. Here we will present measurements of 14C and 10Be measured in proglacial bedrock from Engabreen. Our transects are ca. 600 and 400 meters in front of the modern ice front, and based on historical imagery, was ice covered until the recent past. Initial 10Be results show an increase in concentrations of nearly an order of magnitude from the samples near the center of the glacial trough to those on the lateral margin, consistent with conceptual models of glacial erosion parameterized in terms of sliding velocity. Naïve exposure ages that assume no subglacial erosion range from 0.22 - 9.04 ka. More importantly, we can estimate erosion depths by assuming zero erosion of the highest concentration sample along the two transects and calculate the amount of material removed to yield the lower concentrations elsewhere along the two transects. Results indicate minimum erosion depths of 1-183 cm for most ice

  5. Opposite Effects of Stress on Pain Modulation Depend on the Magnitude of Individual Stress Response.

    Science.gov (United States)

    Geva, Nirit; Defrin, Ruth

    2018-04-01

    The effect of acute stress on pain threshold and intolerance threshold are reported as producing either hypoalgesia or hyperalgesia. Yet, the contribution of individual stress reactivity in this respect has not been established. The aim was to test 2 pain modulation paradigms under acute stress manipulation, to our knowledge, for the first time, to study whether stress differentially affects pain modulation, and whether the effect is related to individual stress response. Participants were 31 healthy subjects. Conditioned pain modulation (CPM) and pain adaptation were measured before and after inducing an acute stress response using the Montreal Imaging Stress Task. Subjects' stress response was evaluated according to salivary cortisol, autonomic function, and perceived stress and anxiety. The Montreal Imaging Stress Task induced a validated stress response. On a group level, stress induced reduction in CPM magnitude and increase in pain adaptation compared with baseline. These responses correlated with stress reactivity. When the group was subdivided according to stress reactivity, only high stress responders exhibited reduced CPM whereas only low stress responders exhibited increased pain adaptation. The results suggest that acute stress may induce opposite effects on pain modulation, depending on individual stress reactivity magnitude, with an advantage to low stress responders. This study evaluated the effect of acute stress on pain modulation. Pain modulation under stress is affected by individual stress responsiveness; decreased CPM occurs in high stress responders whereas increased pain adaptation occurs in low stress responders. Identification of high stress responders may promote better pain management. Copyright © 2017 The American Pain Society. Published by Elsevier Inc. All rights reserved.

  6. The magnitude of interannual variability of ecosystem photosynthetic capacity is controled by stand age and biodiversity

    Science.gov (United States)

    Musavi, Talie; Migliavacca, Mirco; Mahecha, Miguel D.; Reichstein, Markus; Kattge, Jens; Wirth, Christian; Black, T. Andrew; Janssens, Ivan; Knohl, Alexander; Loustau, Denis; Roupsard, Olivier; Varlagin, Andrej; Rambal, Serge; Cescatti, Alessandro; Gianelle, Damiano; Kondo, Hiroaki; Tamrakar, Rijan

    2017-04-01

    Gross primary productivity, GPP, the total uptake of carbon dioxide (CO2) by ecosystems via photosynthesis, is the largest flux in the global carbon cycle. The photosynthetic capacity at light saturation (GPPsat) is a fundamental ecosystem functional property and its interannual variability (IAV) is propagated to the net ecosystem exchange of CO2. In this contribution we made use of a variety of data streams consisting of ecosystem-atmosphere CO2 fluxes measured at eddy covariance flux sites with more than 4 years of data, the GPPsat derived at the different sites, information about climate (temperature, precipitation, and water availability index - WAI), biodiversity information and species richness, stand age, and plant traits, nutrient availability indexes derived from field campaigns, ancillary databases, and the literature. We also used data about forest structure derived from satellite products. Sites were selected according to the availability of eddy covariance flux measurements for at least 4 years, information about stand age, canopy cover, canopy height, and species abundance. The resulting global database consisted of 50 sites with different vegetation types across different climatic regions. Considering the importance of the understanding of IAV in CO2 fluxes to improve the predictive capacity of the global carbon cycle we analyzed a range of alternative hypotheses and potential drivers of the magnitude of IAV in GPPsat in forest ecosystems. The results show that the IAV in GPPsat within sites is driven by climate (i.e. fluctuations in air temperature and soil water availability), but the magnitude of IAV in GPPsat is related to ecosystem structure, and more in details to stand age and biodiversity (R2=0.55, p<0.0001). We conclude that irrespective of forest type the IAV of GPPsat in older and more diverse forests is dampened, and is higher in younger forests with few dominant species.

  7. A first-order second-moment calculation for seismic hazard assessment with the consideration of uncertain magnitude conversion

    Directory of Open Access Journals (Sweden)

    J. P. Wang

    2013-10-01

    Full Text Available Earthquake size can be described with different magnitudes for different purposes. For example, local magnitude ML is usually adopted to compile an earthquake catalog, and moment magnitude Mw is often prescribed by a ground motion model. Understandably, when inconsistent units are encountered in an earthquake analysis, magnitude conversion needs to be performed beforehand. However, the conversion is not expected at full certainty owing to the model error of empirical relationships. This paper introduces a novel first-order second-moment (FOSM calculation to estimate the annual rate of earthquake motion (or seismic hazard on a probabilistic basis, including the consideration of the uncertain magnitude conversion and three other sources of earthquake uncertainties. In addition to the methodology, this novel FOSM application to engineering seismology is demonstrated in this paper with a case study. With a local ground motion model, magnitude conversion relationship and earthquake catalog, the analysis shows that the best-estimate annual rate of peak ground acceleration (PGA greater than 0.18 g (induced by earthquakes is 0.002 per year at a site in Taipei, given the uncertainties of magnitude conversion, earthquake size, earthquake location, and motion attenuation.

  8. A first-order second-moment calculation for seismic hazard assessment with the consideration of uncertain magnitude conversion

    Science.gov (United States)

    Wang, J. P.; Yun, X.; Wu, Y.-M.

    2013-10-01

    Earthquake size can be described with different magnitudes for different purposes. For example, local magnitude ML is usually adopted to compile an earthquake catalog, and moment magnitude Mw is often prescribed by a ground motion model. Understandably, when inconsistent units are encountered in an earthquake analysis, magnitude conversion needs to be performed beforehand. However, the conversion is not expected at full certainty owing to the model error of empirical relationships. This paper introduces a novel first-order second-moment (FOSM) calculation to estimate the annual rate of earthquake motion (or seismic hazard) on a probabilistic basis, including the consideration of the uncertain magnitude conversion and three other sources of earthquake uncertainties. In addition to the methodology, this novel FOSM application to engineering seismology is demonstrated in this paper with a case study. With a local ground motion model, magnitude conversion relationship and earthquake catalog, the analysis shows that the best-estimate annual rate of peak ground acceleration (PGA) greater than 0.18 g (induced by earthquakes) is 0.002 per year at a site in Taipei, given the uncertainties of magnitude conversion, earthquake size, earthquake location, and motion attenuation.

  9. Associations of non-symbolic and symbolic numerical magnitude processing with mathematical competence: a meta-analysis.

    Science.gov (United States)

    Schneider, Michael; Beeres, Kassandra; Coban, Leyla; Merz, Simon; Susan Schmidt, S; Stricker, Johannes; De Smedt, Bert

    2017-05-01

    Many studies have investigated the association between numerical magnitude processing skills, as assessed by the numerical magnitude comparison task, and broader mathematical competence, e.g. counting, arithmetic, or algebra. Most correlations were positive but varied considerably in their strengths. It remains unclear whether and to what extent the strength of these associations differs systematically between non-symbolic and symbolic magnitude comparison tasks and whether age, magnitude comparison measures or mathematical competence measures are additional moderators. We investigated these questions by means of a meta-analysis. The literature search yielded 45 articles reporting 284 effect sizes found with 17,201 participants. Effect sizes were combined by means of a two-level random-effects regression model. The effect size was significantly higher for the symbolic (r = .302, 95% CI [.243, .361]) than for the non-symbolic (r = .241, 95% CI [.198, .284]) magnitude comparison task and decreased very slightly with age. The correlation was higher for solution rates and Weber fractions than for alternative measures of comparison proficiency. It was higher for mathematical competencies that rely more heavily on the processing of magnitudes (i.e. mental arithmetic and early mathematical abilities) than for others. The results support the view that magnitude processing is reliably associated with mathematical competence over the lifespan in a wide range of tasks, measures and mathematical subdomains. The association is stronger for symbolic than for non-symbolic numerical magnitude processing. So symbolic magnitude processing might be a more eligible candidate to be targeted by diagnostic screening instruments and interventions for school-aged children and for adults. © 2016 John Wiley & Sons Ltd.

  10. Flow-type landslides magnitude evaluation: the case study of the Campania Region (Southern Italy)

    Science.gov (United States)

    Santo, Antonio; De Falco, Melania; Di Crescenzo, Giuseppe

    2015-04-01

    In the last years studies concerning the triggering and the run-out susceptibility for different kind of landslides have become more and more precise. In the most of the cases the methodological approach involve the production of detailed thematic maps (at least 1:5000 scale) which represent a very useful tool for territorial planning, especially in urbanized areas. More recently these researches were accompanied by the growth of other studies dealing with landslide magnitude evaluation (especially in terms of volume and velocity estimate). In this paper the results of a flow-type landslides magnitude evaluation are presented. The study area is located in Southern Italy and is very wide (1,500 square kilometres) including all the Campania region. In this context flow type landslides represent the most frequent instabilities as shown by the large number of victims and the huge economic damage caused in the last few centuries. These shallow landslides involve thin cohesionless, unsaturated pyroclastic soils found over steep slopes around Somma-Vesuvio and Phlegrean district, affecting a wide area where over 100 towns are located. Since the potential volume of flow-type landslides is a measure of event magnitude we propose to estimate the potential volume at the scale of slope or basin for about 90 municipalities affecting 850 hierarchized drainage basins and 900 regular slopes. An empirical approach recently proposed in literature (De Falco et al., 2012), allows to estimate the volume of the pyroclastic cover that can be displaced along the slope. The method derives from the interpretation of numerous geological and geomorphological data gathered from a vast amount of case histories on landslides in volcanic and carbonatic contexts and it is based on determining the thickness of the pyroclastic cover and the width of the detachment and erosion-transport zone. Thickness can be evaluated with a good degree of approximation since, in these landslides, the failure

  11. Combining Neural Networks with Existing Methods to Estimate 1 in 100-Year Flood Event Magnitudes

    Science.gov (United States)

    Newson, A.; See, L.

    2005-12-01

    Over the last fifteen years artificial neural networks (ANN) have been shown to be advantageous for the solution of many hydrological modelling problems. The use of ANNs for flood magnitude estimation in ungauged catchments, however, is a relatively new and under researched area. In this paper ANNs are used to make estimates of the magnitude of the 100-year flood event (Q100) for a number of ungauged catchments. The data used in this study were provided by the Centre for Ecology and Hydrology's Flood Estimation Handbook (FEH), which contains information on catchments across the UK. Sixteen catchment descriptors for 719 catchments were used to train an ANN, which was split into a training, validation and test data set. The goodness-of-fit statistics on the test data set indicated good model performance, with an r-squared value of 0.8 and a coefficient of efficiency of 79 percent. Data for twelve ungauged catchments were then put through the trained ANN to produce estimates of Q100. Two other accepted methodologies were also employed: the FEH statistical method and the FSR (Flood Studies Report) design storm technique, both of which are used to produce flood frequency estimates. The advantage of developing an ANN model is that it provides a third figure to aid a hydrologist in making an accurate estimate. For six of the twelve catchments, there was a relatively low spread between estimates. In these instances, an estimate of Q100 could be made with a fair degree of certainty. Of the remaining six catchments, three had areas greater than 1000km2, which means the FSR design storm estimate cannot be used. Armed with the ANN model and the FEH statistical method the hydrologist still has two possible estimates to consider. For these three catchments, the estimates were also fairly similar, providing additional confidence to the estimation. In summary, the findings of this study have shown that an accurate estimation of Q100 can be made using the catchment descriptors of

  12. The magnitude and selectivity of natural and multiple anthropogenic mortality causes in hunted brown bears.

    Science.gov (United States)

    Bischof, Richard; Swenson, Jon E; Yoccoz, Nigel G; Mysterud, Atle; Gimenez, Olivier

    2009-05-01

    1. The population dynamic and evolutionary effects of harvesting are receiving growing attention among biologists. Cause-specific estimates of mortality are necessary to determine and compare the magnitude and selectivity of hunting and other types of mortalities. In addition to the logistic and financial constraints on longitudinal studies, they are complicated by the fact that nonhunting mortality in managed populations usually consists of a mix of natural and human-caused factors. 2. We used multistate capture-recapture (MCR) models to estimate cause-specific survival of brown bears (Ursus arctos) in two subpopulations in Sweden over a 23-year period. In our analysis, we distinguished between legal hunting and other sources of mortality, such as intraspecific predation, accidents, poaching, and damage control removals. We also tested whether a strong increase in harvest quotas after 1997 in one of the subpopulations affected vulnerability to legal hunting. 3. Although only a fraction of mortalities other than legal hunting could be considered natural, this group of causes showed a general pattern of demographic selectivity expected from natural mortality regimes in populations of long-lived species, namely greater vulnerability of young animals. On the other hand, demographic effects on hunting vulnerability were weak and inconsistent. Our findings support the assumption that hunting and other mortalities were additive. 4. As expected, an increase in hunting pressure coincided with a correspondingly large increase in vulnerability to hunting in the affected subpopulation. Because even unbiased harvest can lead to selective pressures on life-history traits, such as size at primiparity, increasing harvest quotas may not only affect population growth directly, but could also alter optimal life-history strategies in brown bears and other carnivores. 5. Legal hunting is the most conveniently assessed and the most easily managed cause of mortality in many wild

  13. A statistical analysis of afterschock sequences from a temporal and magnitude standpoint

    International Nuclear Information System (INIS)

    Mohammadioun, G.

    1990-07-01

    Until quite recently indeed in its history, mankind has been inclined to regard earthquakes, like most other natural phenomena, as veritable acts of God, and as such unpredictable by definition. This attitude began to evolve only after scientists succeeded in explaining these catastrophic events as resulting, most often, from displacement along fault planes involved in tectonic processes. With the natural origin of earthquakes thus firmly established, the idea logically took root that they might actually not be so unpredictable after all. Even then, attention at first focused principally upon large, damage-causing events to the exclusion of all others. Only very lately have earthquakes begun to be viewed, not as punctual, isolated occurrences, but rather as composite 'histories', extending outwards in time and space and implying complex causal ramifications. In this light, pattern recognition techniques, among others, could then pertinently be brought to bear upon the problem of earthquake prediction. Aftershocks and foreshocks can now accordingly be integrated into an overall scheme reflecting the conditions at any given moment on a fault or fault system. First used in the past to map the portion of a fault that had been activated in the course of a major earthquake, these lesser events can be also analyzed from a prediction standpoint, leastwise the prediction of potentially damaging aftershocks. The very definition of the aftershock concept is in fact not as clearcut as it might appear at first sight. Aftershocks are generally thought of as events with relatively insignificant magnitudes. In reality, many aftershock sequences contain events as strong or almost as strong as the so-called mainshock, and the main shock itself, if its magnitude is 6 or more, stands a good chance of being a multiple event, with two or more shocks in rapid succession (within seconds or fractions thereof). The question may also arise as to when a seismic event oc curing at the same

  14. The MACHO Project 9 Million Star Color-Magnitude Diagram of the Large Magellanic Cloud

    International Nuclear Information System (INIS)

    Alcock, C.; Allsman, R. A.; Alves, D. R.; Axelrod, T. S.; Basu, A.; Becker, A. C.; Bennett, D. P.; Cook, K. H.; Drake, A. J.; Freeman, K. C.

    2000-01-01

    We present a 9 million star color-magnitude diagram (9M CMD) of the Large Magellanic Cloud (LMC) bar. The 9M CMD reveals a complex superposition of different-age and -metallicity stellar populations, with important stellar evolutionary phases occurring over 3 orders of magnitude in number density. First, we count the nonvariable red and blue supergiants and the associated Cepheid variables and measure the stellar effective temperatures defining the Cepheid instability strip. Lifetime predictions of stellar evolution theory are tested, with implications for the origin of low-luminosity Cepheids. The highly evolved asymptotic giant branch (AGB) stars in the 9M CMD have a bimodal distribution in brightness, which we interpret as discrete old populations ((greater-or-similar sign)1 Gyr). The faint AGB sequence may be metal-poor and very old. Comparing the mean properties of giant branch and horizontal-branch (HB) stars in the 9M CMD with those of clusters, we identify NGC 411 and M3 as templates for the admixture of old stellar populations in the bar. However, there are several indications that the old and metal-poor field population has a red HB morphology: the RR Lyrae variables lie preferentially on the red edge of the instability strip, the AGB bump is very red, and the ratio of AGB bump stars to RR Lyrae variables is quite large. If the HB second parameter is age, the old and metal-poor field population in the bar likely formed after the oldest LMC clusters. Lifetime predictions of stellar evolution theory lead us to associate a significant fraction of the ∼1 million red HB clump giants in the 9M CMD with the same old and metal-poor population producing the RR Lyrae stars and the AGB bump. In this case, compared with the age-dependent luminosity predictions of stellar evolution theory, the red HB clump is too bright relative to the RR Lyrae stars and AGB bump. Last, we show that the surface density profile of RR Lyrae variables is fitted by an exponential

  15. Mapping of forest disturbance magnitudes across the US National Forest System

    Science.gov (United States)

    Hernandez, A. J.; Healey, S. P.; Ramsey, R. D.; McGinty, C.; Garrard, C.; Lu, N.; Huang, C.

    2013-12-01

    A precise record in conjunction with ongoing monitoring of carbon pools constitutes essentials inputs for the continuous modernization of an ever- dynamic science such as climate change. This is particularly important in forested ecosystems for which accurate field archives are available and can be used in combination with historic satellite imagery to obtain spatially explicit estimates of several indicators that can be used in the assessment of said carbon pools. Many forest disturbance processes limit storage of carbon in forested ecosystems and thereby reduce those systems' capacity to mitigate changes in the global climate system. A component of the US National Forest System's (NFS) comprehensive plan for carbon monitoring includes accounting for mapped disturbances, such as fires, harvests, and insect activity. A long-term time series of maps that show the timing, extent, type, and magnitude of disturbances going back to 1990 has been prepared for the United States Forest Service (USFS) Northern Region, and is currently under preparation for the rest of the NFS regions covering more than 75 million hectares. Our mapping approach starts with an automated initial detection of annual disturbances using imagery captured within the growing season from the Landsat archive. Through a meticulous process, the initial detections are then visually inspected, manually corrected and labeled using various USFS ancillary datasets and Google Earth high-resolution historic imagery. We prepared multitemporal models of percent canopy cover and live tree carbon (T/ha) that were calibrated with extensive (in excess of 2000 locations) field data from the US Forest Service Forest Inventory and Analysis program (FIA). The models were then applied to all the years of the radiometrically corrected and normalized Landsat time series in order to provide annual spatially explicit estimates of the magnitude of change in terms of these two attributes. Our results provide objective, widely

  16. Spectral Variability of the UXOR Star RR Tau Over 2.5 Magnitudes in V

    Science.gov (United States)

    Rodgers, B.; Wooden, D. H.; Grinin, V. P.; Shakhovskoy, D.

    2000-12-01

    We present moderate resolution optical spectra of the highly variable Herbig Ae star RR Tau over 12 epochs spanning 2.5 magnitudes in V. The data cover most of the optical spectrum from the CaII K line in the blue to the CaII infrared triplet in the far red. Using contemporaneous photometric measurements from two sources, we have reliable estimates of the visual magnitude of the system at each spectral epoch. We find some spectral activity to be closely correlated with photometric variability, while other features are remarkably stable. Significant variability is common in the cores of Hα and Hβ , but is not well correlated with photometric variability. On the other hand, the wings (Δ v>400km/s) of the Balmer lines are quite stable, showing no change in spectral type when compared to Kurucz line profiles. This, along with the constant equivalent width seen in several weak metal lines, suggest that the physical conditions of the underlying continuum source are not changing significantly, despite a factor of ten change in brightness. In contrast, strong low-ionization permitted lines, such as FeII, CaII and NaI, are seen in deep absorption when the star is bright (V <= 12), but disappear during photometric minima to reveal weak emission lines. These absorption lines are not being filled in by the emission but rather are physically disappearing from the system. This could occur, for example, if an obscuring screen moved between the continuum source and the absorbing gas. The [OI]6300 line, a common wind diagnostic, is seen in emission at all epochs, with flux which is roughly constant except increasing slightly when the system is faint. We discuss these data in the context of different scenarios for the photometric variability and find them to be more consistent with the obscuration hypothesis, than changing accretion luminosity. This work is part of the dissertation research of B. Rodgers, which has been funded in large part by a NASA Graduate Student Research

  17. The MACHO Project 9 Million Star Color-Magnitude Diagram of the Large Magellanic Cloud

    Energy Technology Data Exchange (ETDEWEB)

    Alcock, C.; Allsman, R. A.; Alves, D. R.; Axelrod, T. S.; Basu, A.; Becker, A. C.; Bennett, D. P.; Cook, K. H.; Drake, A. J.; Freeman, K. C. (and others)

    2000-05-01

    We present a 9 million star color-magnitude diagram (9M CMD) of the Large Magellanic Cloud (LMC) bar. The 9M CMD reveals a complex superposition of different-age and -metallicity stellar populations, with important stellar evolutionary phases occurring over 3 orders of magnitude in number density. First, we count the nonvariable red and blue supergiants and the associated Cepheid variables and measure the stellar effective temperatures defining the Cepheid instability strip. Lifetime predictions of stellar evolution theory are tested, with implications for the origin of low-luminosity Cepheids. The highly evolved asymptotic giant branch (AGB) stars in the 9M CMD have a bimodal distribution in brightness, which we interpret as discrete old populations ((greater-or-similar sign)1 Gyr). The faint AGB sequence may be metal-poor and very old. Comparing the mean properties of giant branch and horizontal-branch (HB) stars in the 9M CMD with those of clusters, we identify NGC 411 and M3 as templates for the admixture of old stellar populations in the bar. However, there are several indications that the old and metal-poor field population has a red HB morphology: the RR Lyrae variables lie preferentially on the red edge of the instability strip, the AGB bump is very red, and the ratio of AGB bump stars to RR Lyrae variables is quite large. If the HB second parameter is age, the old and metal-poor field population in the bar likely formed after the oldest LMC clusters. Lifetime predictions of stellar evolution theory lead us to associate a significant fraction of the {approx}1 million red HB clump giants in the 9M CMD with the same old and metal-poor population producing the RR Lyrae stars and the AGB bump. In this case, compared with the age-dependent luminosity predictions of stellar evolution theory, the red HB clump is too bright relative to the RR Lyrae stars and AGB bump. Last, we show that the surface density profile of RR Lyrae variables is fitted by an exponential

  18. Seyle’s biological stressors influence dramatically skin physiology: our experiences with electrical admittance magnitude measurements

    Directory of Open Access Journals (Sweden)

    Lorenzo Martini

    2014-04-01

    Full Text Available Introduction: Abrupt changes of environmental temperatures and assault of chemical and physical assaults belong to the series of biological stresses recorded by the austro-canadian endocrinologist Seyle onto skin, phenomena that are progressively overset all natural events and anthropological lifestyles, are too often depreciated and underestimated by dermatologists and cosmetologists at all. Aims of our study is to evaluate by electrical admittance magnitude measurements the influence these two irrefutable afflictions, designed as stressors, influence negatively human skin and to do this we have selected, to conduct the study, peculiar individuals that, owing to their choice of living, may or not be injured by extreme changes of temperatures and aggressions by chemical and physical pollutants. Materials and Methods: We have recruited 20 nuns in a cloistered convent in Mid Italy: ten of these have been always accustomed to live inside the cloister and their life-style permits the good conservation of the intact skin physiology (that is living at air temperature and medium-low relative humidity and the other ten are accustomed to live and work outdoor and to be assaulted by abrupt and extreme changes of environmental temperature and pollutants. Cloistered nuns have the chance to choose where to live, indoor or aoutdoor. We measured the electrical admittance magnitude (in μmho at the beginning and at the end of the experiment that lasts 29 weeks, using an appropriate instrument based on the system developed by Feldman, working at a single frequency of 30kHz. Results and Conclusion: It is self evident that after the simulation of phyto-induced cortisol release onto the skins of all the 20 volunteers, the subjects that which live outdoor show an exaggerated value of dehydration with regard to the subjects that live indoor. Changes of environmental temperatures and chemical pollutants, is self evident, jeopardize human skin integrity and safety, but

  19. Landscape scale assessment of ecosystem goods and services and the extent, location, and magnitude of urban-suburban expansion

    Science.gov (United States)

    Human development adjoining coastal cities is the prevalent force changing the Anthropocene landscape. The extent, location, and magnitude of urban-suburban expansion can drastically modify how important features of ecosystems are effected. These effects are best summarized usin...

  20. Analyses and Simulation of 3D Scattering Due to Heterogeneous Crustal Structure and Surface Topography on Regional Phases, Magnitude Discrimination

    National Research Council Canada - National Science Library

    Pitarka, Arban; Helmberger, Don V; Ni, Sidao

    2008-01-01

    ... into ongoing research for the development of simple empirical models of scattering that can be used in reducing the scatter in measures of Lg and coda wave magnitude and for discrimination purposes as well...

  1. Parameters and a magnitude moment relationship from small earthquakes observed during hydraulic fracturing experiments in crystalline rocks

    Energy Technology Data Exchange (ETDEWEB)

    Pearson, C.

    1982-04-01

    Using source parameters estimated from seismic spectra and magnitudes estimated from coda lengths, we demonstrate that the log-linear relationship between moment and magnitude holds for events with magnitudes as low as -6. Using, as a data set, events induced by hydraulic fracturing experiments at the Fenton Hill, New Mexico, Hot Dry Rock (HDR) geothermal site, we find that the relationship between magnitude M and seismic moment (Mo) is log (Mo) = 17.27+0.77 M Moreover, the linear relationship between seismic moment and source radius (r) holds for the Fenton Hill microearthquakes. Analyses of the Fenton Hill data yield the following relationship. log (r) = 2.28+0.19 log (Mo)

  2. Effects of reinforcer magnitude on data-entry productivity in chronically unemployed drug abusers participating in a Therapeutic Workplace.

    Science.gov (United States)

    Wong, Conrad J; Sheppard, Jeannie-Marie; Dallery, Jesse; Bedient, Guy; Robles, Elias; Svikis, Dace; Silverman, Kenneth

    2003-02-01

    The Therapeutic Workplace is a substance abuse treatment wherein patients are hired and paid to work in a job contingent on daily drug-free urine samples. The present study examined data-entry productivity of 6 unemployed methadone patients who demonstrated relatively variable and low data-entry response rates. A within-subject reversal design was used to determine whether increasing reinforcement magnitude tenfold could increase response rates. Four of the 6 participants showed the highest rates of responding in the high magnitude reinforcement condition. Two participants, who had the lowest overall response rates, showed less robust changes to the magnitude manipulation. The results suggest that reinforcement magnitude can be used to improve productivity in Therapeutic Workplace participants.

  3. Effect of Bend Radius on Magnitude and Location of Erosion in S-Bend

    Directory of Open Access Journals (Sweden)

    Quamrul H. Mazumder

    2015-01-01

    Full Text Available Solid particle erosion is a mechanical process that removes material by the impact of solid particles entrained in the flow. Erosion is a leading cause of failure of oil and gas pipelines and fittings in fluid handling industries. Different approaches have been used to control or minimize damage caused by erosion in particulated gas-solid or liquid-solid flows. S-bend geometry is widely used in different fluid handling equipment that may be susceptible to erosion damage. The results of a computational fluid dynamic (CFD simulation of diluted gas-solid and liquid-solid flows in an S-bend are presented in this paper. In addition to particle impact velocity, the bend radius may have significant influence on the magnitude and the location of erosion. CFD analysis was performed at three different air velocities (15.24 m/s–45.72 m/s and three different water velocities (0.1 m/s–10 m/s with entrained solid particles. The particle sizes used in the analysis range between 50 and 300 microns. Maximum erosion was observed in water with 10 m/s, 250-micron particle size, and a ratio of 3.5. The location of maximum erosion was observed in water with 10 m/s, 300-micron particle size, and a ratio of 3.5. Comparison of CFD results with available literature data showed reasonable and good agreement.

  4. Effect of reinforcer magnitude on performance maintained by progressive-ratio schedules.

    Science.gov (United States)

    Rickard, J F; Body, S; Zhang, Z; Bradshaw, C M; Szabadi, E

    2009-01-01

    This experiment examined the relationship between reinforcer magnitude and quantitative measures of performance on progressive-ratio schedules. Fifteen rats were trained under a progressive-ratio schedule in seven phases of the experiment in which the volume of a 0.6-M sucrose solution reinforcer was varied within the range 6-300 microl. Overall response rates in successive ratios conformed to a bitonic equation derived from Killeen's (1994) Mathematical Principles of Reinforcement. The "specific activation" parameter, a, which is presumed to reflect the incentive value of the reinforcer, was a monotonically increasing function of reinforcer volume; the "response time" parameter, delta, which defines the minimum response time, increased as a function of reinforcer volume; the "currency" parameter, beta, which is presumed to reflect the coupling of responses to the reinforcer, declined as a function of volume. Running response rate (response rate calculated after exclusion of the postreinforcement pause) decayed monotonically as a function of ratio size; the index of curvature of this function increased as a function of reinforcer volume. Postreinforcement pause increased as a function of ratio size. Estimates of a derived from overall response rates and postreinforcement pauses showed a modest positive correlation across conditions and between animals. Implications of the results for the quantification of reinforcer value and for the use of progressive-ratio schedules in behavioral neuroscience are discussed.

  5. Surveying the range and magnitude of alcohol's harm to others in Australia.

    Science.gov (United States)

    Laslett, Anne-Marie; Room, Robin; Ferris, Jason; Wilkinson, Claire; Livingston, Michael; Mugavin, Janette

    2011-09-01

    This study aims to document the adverse effects of drinkers in Australia on people other than the drinker. Cross-sectional survey. In a national survey of Australia, respondents described the harmful effects they experienced from drinkers in their households, family and friendship networks, as well as work-place and community settings. A randomly selected sample of 2,649 adult Australians. Problems experienced because of others' drinking were ascertained via computer-assisted telephone interviews. Respondent and drinker socio-demographic and drinking pattern data were recorded. A total of 70% of respondents were affected by strangers' drinking and experienced nuisance, fear or abuse, and 30% reported that the drinking of someone close to them had negative effects, although only 11% were affected by such a person 'a lot'. Women were more affected by someone they knew in the household or family, while men were more affected by strangers, friends and co-workers. Young adults were consistently the most negatively affected across the majority of types of harm. Substantial proportions of Australians are affected by other people's drinking, including that of their families, friends, co-workers and strangers. These harms range in magnitude from noise and fear to physical abuse, sexual coercion and social isolation. © 2011 The Authors, Addiction © 2011 Society for the Study of Addiction.

  6. The 2012 Pianura Padana Emiliana seimic sequence: locations, moment tensors and magnitudes

    Directory of Open Access Journals (Sweden)

    Laura Scognamiglio

    2012-10-01

    Full Text Available On May 20, 2012 (02:03:53 UTC, an Mw 5.86 (Ml 5.9 earthquake struck the Pianura Padana Emiliana region (northern Italy, causing five deaths and damage to several villages and to the towns of Ferrara and Modena. The mainshock was preceded, three hours earlier, by a Mw 3.98 (Ml 4.1 foreshock, which almost co-located with the main event. After the main event, the seismic sequence included six earthquakes with magnitudes >5.0. The biggest aftershock was located about 12 km west of the first mainshock, and was a Mw 5.66 (Ml 5.8 earthquake that occurred on May 29, 2012 (07:00:03 UTC; this can be considered as a second mainshock. After this event, the official death toll of the seismic sequence was 17 people. Moreover, there had been severe damage to the economy of the region and there were 13,000 homeless. [...]    

  7. College Student Samples Are Not Always Equivalent: The Magnitude of Personality Differences Across Colleges and Universities.

    Science.gov (United States)

    Corker, Katherine S; Donnellan, M Brent; Kim, Su Yeong; Schwartz, Seth J; Zamboanga, Byron L

    2017-04-01

    This research examined the magnitude of personality differences across different colleges and universities to understand (a) how much students at different colleges vary from one another and (b) whether there are site-level variables that can explain observed differences. Nearly 8,600 students at 30 colleges and universities completed a Big Five personality trait measure. Site-level information was obtained from the Integrated Postsecondary Education System database (U.S. Department of Education). Multilevel models revealed that each of the Big Five traits showed significant between-site variability, even after accounting for individual-level demographic differences. Some site-level variables (e.g., enrollment size, requiring letters of recommendation) explained between-site differences in traits, but many tests were not statistically significant. Student samples at different universities differed in terms of average levels of Big Five personality domains. This raises the possibility that personality differences may explain differences in research results obtained when studying students at different colleges and universities. Furthermore, results suggest that research that compares findings for only a few sites (e.g., much cross-cultural research) runs the risk of overgeneralizing differences between specific samples to broader group differences. These results underscore the value of multisite collaborative research efforts to enhance psychological research. © 2015 Wiley Periodicals, Inc.

  8. Two orders of magnitude reduction in silicon membrane thermal conductivity by resonance hybridizations

    Science.gov (United States)

    Honarvar, Hossein; Hussein, Mahmoud I.

    2018-05-01

    The thermal conductivity of a freestanding single-crystal silicon membrane may be reduced significantly by attaching nanoscale pillars on one or both surfaces. Atomic resonances of the nanopillars form vibrons that intrinsically couple with the base membrane phonons causing mode hybridization and flattening at each coupling location in the phonon band structure. This in turn causes group velocity reductions of existing phonons, in addition to introducing new modes that get excited but are localized and do not transport energy. The nanopillars also reduce the phonon lifetimes at and around the hybridization zones. These three effects, which in principle may be tuned to take place across silicon's full spectrum, lead to a lowering of the in-plane thermal conductivity in the base membrane. Using equilibrium molecular dynamics simulations, and utilizing the concept of vibrons compensation, we report a staggering two orders of magnitude reduction in the thermal conductivity at room temperature by this mechanism. Specifically, a reduction of a factor of 130 is demonstrated for a roughly 10-nm-thick pillared membrane compared to a corresponding unpillared membrane. This amounts to a record reduction of a factor of 481 compared to bulk crystalline silicon and nearly a factor of 2 compared to bulk amorphous silicon. These results are obtained while providing a path for preserving performance with upscaling.

  9. Magnitude and outcomes of road traffic accidents at Hospitals in Wolaita Zone, SNNPR, Ethiopia.

    Science.gov (United States)

    Hailemichael, Feleke; Suleiman, Mohammed; Pauolos, Wondimagegn

    2015-04-09

    A Road traffic accident is an incident on a way or street open to public traffic, resulting in one or more persons being killed or injured, and involving at least one moving vehicle. The aim of this study is to assess magnitude and outcome of road traffic accidents among trauma victims at hospitals in Wolaita zone. A cross sectional hospital based study design using retrospective chart review was conducted from March 5th to March 25th, 2014. Simple random sampling technique was applied to identify sample population. The data was entered in to Epi info version 3.5.1 and transferred to SPSS version 16 for further analysis. A total of 384 trauma victims were incorporated in the study of which 240 (62.5%) were due to road traffic accidents. The majority of patients were male 298 (77.6%) and most commonly aged between 20-29 (35.42%). The principal outcome of injury was more commonly lower extremity (182 patients, 47.4%), compared to upper extremity (126 patients, 32.8%). Of all trauma patient presenting to hospitals (62.5%) are the result of road traffic accident. Hence, the provision of tailored messages to all members of the community regarding knowledge and practices of road safety measures like appropriate use of pavements by pedestrians and avoiding risky driving behaviors. Besides this make use of compulsory motorcycle helmets would appear to be a very important intervention.

  10. Effect of binary fraction on color-magnitude diagram of NGC 1904

    Science.gov (United States)

    Li, Zhongmu; Deng, Yangyang

    2018-05-01

    The age of a southern globular cluster in Milky Way, NGC 1904, was shown to be larger than the typical age of the universe, around 13.7 Gyr, by some photometric studies which assumed all stars as single stars. Besides the uncertainties in photometry, isochrone and fitting technique, the neglect of binary stars possibly distorted the result. We study the effect of binary fraction on the color-magnitude diagram (CMD) of NGC 1904, via a new tool for CMD studies, Powerful CMD, which can determine binary fraction, age, metallicity, distance modulus, color excess, rotating star fraction and star formation history simultaneously. We finally obtain the youngest age of 14.1±2.1 Gyr with a zero-age binary fraction of 60 percent for cluster NGC 1904. The result is consistent with the age of the universe. Although our result suggests that binary fraction affects the determination of age slightly, it can improve the fitting to observed CMD, in particular blue stragglers. This suggests us to consider the effect of binaries in the studies of star clusters.

  11. Response format, magnitude of laterality effects, and sex differences in laterality.

    Science.gov (United States)

    Voyer, Daniel; Doyle, Randi A

    2012-01-01

    The present study examined the evidence for the claim that response format might affect the magnitude of laterality effects by means of a meta-analysis. The analysis included the 396 effect sizes drawn from 266 studies retrieved by Voyer (1996) and relevant to the main effect of laterality and sex differences in laterality for verbal and non-verbal tasks in the auditory, tactile, and visual sensory modality. The response format used in specific studies was the only moderator variable of interest in the present analysis, resulting in four broad response categories (oral, written, computer, and pointing). A meta-analysis analogue to ANOVA showed no significant influence of response format on either the main effect of laterality or sex differences in laterality when all sensory modalities were combined. However, when modalities were considered separately, response format affected the main effect of laterality in the visual modality, with a clear advantage for written responses. Further pointed analyses revealed some specific differences among response formats. Results are discussed in terms of their implications for the measurement of laterality.

  12. Anthropometric Characteristics and Sex Influence Magnitude of Skin Cooling following Exposure to Whole Body Cryotherapy

    Science.gov (United States)

    Hammond, L. E.; Cuttell, S.; Nunley, P.; Meyler, J.

    2014-01-01

    This study explored whether anthropometric measures influence magnitude of skin cooling following exposure to whole body cryotherapy (WBC). Height, weight, body fat percentage, and lean mass were measured in 18 male and 14 female participants. Body surface area, body surface area to mass ratio, body mass index, fat-free mass index, and fat mass index were calculated. Thermal images were captured before and after WBC (−60°C for 30 seconds, −110°C for 2 minutes). Skin temperature was measured at the chest, arm, thigh, and calf. Mean skin temperature before and after WBC and change in mean skin temperature (ΔT sk) were calculated. ΔT sk was significantly greater in females (12.07 ± 1.55°C) than males (10.12 ± 1.86°C; t(30) = −3.09, P = .004). A significant relationship was observed between body fat percentage and ΔT sk in the combined dataset (P = .002, r = .516) and between fat-free mass index and ΔT sk in males (P = .005, r = .622). No other significant associations were found. Skin response of individuals to WBC appears to depend upon anthropometric variables and sex, with individuals with a higher adiposity cooling more than thinner individuals. Effects of sex and anthompometrics should be considered when designing WBC research or treatment protocols. PMID:25061612

  13. Bridging Three Orders of Magnitude: Multiple Scattered Waves Sense Fractal Microscopic Structures via Dispersion

    Science.gov (United States)

    Lambert, Simon A.; Näsholm, Sven Peter; Nordsletten, David; Michler, Christian; Juge, Lauriane; Serfaty, Jean-Michel; Bilston, Lynne; Guzina, Bojan; Holm, Sverre; Sinkus, Ralph

    2015-08-01

    Wave scattering provides profound insight into the structure of matter. Typically, the ability to sense microstructure is determined by the ratio of scatterer size to probing wavelength. Here, we address the question of whether macroscopic waves can report back the presence and distribution of microscopic scatterers despite several orders of magnitude difference in scale between wavelength and scatterer size. In our analysis, monosized hard scatterers 5 μ m in radius are immersed in lossless gelatin phantoms to investigate the effect of multiple reflections on the propagation of shear waves with millimeter wavelength. Steady-state monochromatic waves are imaged in situ via magnetic resonance imaging, enabling quantification of the phase velocity at a voxel size big enough to contain thousands of individual scatterers, but small enough to resolve the wavelength. We show in theory, experiments, and simulations that the resulting coherent superposition of multiple reflections gives rise to power-law dispersion at the macroscopic scale if the scatterer distribution exhibits apparent fractality over an effective length scale that is comparable to the probing wavelength. Since apparent fractality is naturally present in any random medium, microstructure can thereby leave its fingerprint on the macroscopically quantifiable power-law exponent. Our results are generic to wave phenomena and carry great potential for sensing microstructure that exhibits intrinsic fractality, such as, for instance, vasculature.

  14. From rational numbers to algebra: separable contributions of decimal magnitude and relational understanding of fractions.

    Science.gov (United States)

    DeWolf, Melissa; Bassok, Miriam; Holyoak, Keith J

    2015-05-01

    To understand the development of mathematical cognition and to improve instructional practices, it is critical to identify early predictors of difficulty in learning complex mathematical topics such as algebra. Recent work has shown that performance with fractions on a number line estimation task predicts algebra performance, whereas performance with whole numbers on similar estimation tasks does not. We sought to distinguish more specific precursors to algebra by measuring multiple aspects of knowledge about rational numbers. Because fractions are the first numbers that are relational expressions to which students are exposed, we investigated how understanding the relational bipartite format (a/b) of fractions might connect to later algebra performance. We presented middle school students with a battery of tests designed to measure relational understanding of fractions, procedural knowledge of fractions, and placement of fractions, decimals, and whole numbers onto number lines as well as algebra performance. Multiple regression analyses revealed that the best predictors of algebra performance were measures of relational fraction knowledge and ability to place decimals (not fractions or whole numbers) onto number lines. These findings suggest that at least two specific components of knowledge about rational numbers--relational understanding (best captured by fractions) and grasp of unidimensional magnitude (best captured by decimals)--can be linked to early success with algebraic expressions. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Magnitude and Correlates of Anemia in Elderly Women of a Resettlement Colony of Delhi.

    Science.gov (United States)

    Singh, Tulika; Nagesh, S; Ray, T K

    2018-01-01

    Anemia of any degree contributes significantly to morbidity and mortality and has a significant effect on the quality of life of elderly women. Despite its clinical importance, anemia in the elderly women is underrecognized. The objective of this study was to assess the magnitude and correlates of anemia in elderly women of a resettlement colony of Delhi. A community-based, cross-sectional study for the duration of 1 year was conducted among 512 geriatric women (≥60 years). Demographic characteristics, dietary assessment, and behavioral risk factors were determined by interview, and the participants underwent physical examination followed by hemoglobin estimation by HemoCue. Anemia was defined using the WHO criteria of hemoglobin <12 g/dl. Chi-square test was employed to study the association between sociodemographic factors and anemia followed by multivariate regression analysis. The prevalence of anemia was 79.9% according to the WHO criteria of hemoglobin <12 g/dl in females. Age, education, marital status, financial dependence, diagnosed chronic disease, diet, calorie intake, history of worm infestation, and body mass index (BMI) were significantly associated with anemia on univariate analysis. In multivariate analysis, age, marital status, financial dependence, diagnosed chronic disease, diet, calorie intake, and BMI were significant explanatory variables for anemia. Our study points out high prevalence of and some of the major factors associated with anemia in elderly women. The need of the hour is to include our elderly women under the gamut of National Anemia Prophylaxis Program.

  16. Distribution and Magnitude of Dinitrogen Fixation in the Eastern Tropical North Pacific Oxygen Deficient Zone.

    Science.gov (United States)

    Selden, C.; Mulholland, M. R.; Widner, B.; Bernhardt, P. W.; Macías Tapia, A.; Jayakumar, A.

    2016-12-01

    The Eastern Tropical North Pacific Ocean (ETNP) hosts one of the world's three major open ocean oxygen deficient zones (ODZs). Hotspots for fixed nitrogen (N) loss processes, ODZs have classically been discounted as areas of significant dinitrogen (N2) fixation, the microbe-mediated reduction of N2 to ammonium (NH4+), which has historically been ascribed primarily to euphotic, nutrient-deplete tropical waters. Challenging this paradigm, active expression of nifH (the dinitrogen reductase structural gene) has recently been documented in the ETNP, Eastern Tropical South Pacific, and Arabian Sea ODZs, implying a closer coupling of fixed nitrogen input and loss processes than previously thought. Here, we report rates of N­2 fixation measured in the ETNP ODZ along vertical gradients of oxygen, light, and dissolved N concentrations. Detailed vertical profiles of N2 fixation rates and dissolved N concentrations made within the ODZ were compared with similar profiles from oxic waters outside the ODZ. In addition, different organic carbon sources were investigated as potential rate-limiting factors for N2 fixation in sub-euphotic waters. By establishing the magnitude and distribution of N­2 fixation in the ETNP ODZ, this study contributes to current understanding of N cycling in anoxic and aphotic waters, and serves to elucidate nuances in the global N budget, enabling more accurate biogeochemical modeling. Understanding these processes in present day ODZs is crucial for predicting how ongoing anthropogenic intensification of coastal ODZs will alter biogeochemical cycles in the future.

  17. Exercise-induced bone formation is poorly linked to local strain magnitude in the sheep tibia.

    Directory of Open Access Journals (Sweden)

    Ian J Wallace

    Full Text Available Functional interpretations of limb bone structure frequently assume that diaphyses adjust their shape by adding bone primarily across the plane in which they are habitually loaded in order to minimize loading-induced strains. Here, to test this hypothesis, we characterize the in vivo strain environment of the sheep tibial midshaft during treadmill exercise and examine whether this activity promotes bone formation disproportionately in the direction of loading in diaphyseal regions that experience the highest strains. It is shown that during treadmill exercise, sheep tibiae were bent in an anteroposterior direction, generating maximal tensile and compressive strains on the anterior and posterior shaft surfaces, respectively. Exercise led to significantly increased periosteal bone formation; however, rather than being biased toward areas of maximal strains across the anteroposterior axis, exercise-related osteogenesis occurred primarily around the medial half of the shaft circumference, in both high and low strain regions. Overall, the results of this study demonstrate that loading-induced bone growth is not closely linked to local strain magnitude in every instance. Therefore, caution is necessary when bone shaft shape is used to infer functional loading history in the absence of in vivo data on how bones are loaded and how they actually respond to loading.

  18. Evaluating Annual Maximum and Partial Duration Series for Estimating Frequency of Small Magnitude Floods

    Directory of Open Access Journals (Sweden)

    Fazlul Karim

    2017-06-01

    Full Text Available Understanding the nature of frequent floods is important for characterising channel morphology, riparian and aquatic habitat, and informing river restoration efforts. This paper presents results from an analysis on frequency estimates of low magnitude floods using the annual maximum and partial series data compared to actual flood series. Five frequency distribution models were fitted to data from 24 gauging stations in the Great Barrier Reef (GBR lagoon catchments in north-eastern Australia. Based on the goodness of fit test, Generalised Extreme Value, Generalised Pareto and Log Pearson Type 3 models were used to estimate flood frequencies across the study region. Results suggest frequency estimates based on a partial series are better, compared to an annual series, for small to medium floods, while both methods produce similar results for large floods. Although both methods converge at a higher recurrence interval, the convergence recurrence interval varies between catchments. Results also suggest frequency estimates vary slightly between two or more partial series, depending on flood threshold, and the differences are large for the catchments that experience less frequent floods. While a partial series produces better frequency estimates, it can underestimate or overestimate the frequency if the flood threshold differs largely compared to bankfull discharge. These results have significant implications in calculating the dependency of floodplain ecosystems on the frequency of flooding and their subsequent management.

  19. Direct magnitude estimates of speech intelligibility in dysarthria: effects of a chosen standard.

    Science.gov (United States)

    Weismer, Gary; Laures, Jacqueline S

    2002-06-01

    Direct magnitude estimation (DME) has been used frequently as a perceptual scaling technique in studies of the speech intelligibility of persons with speech disorders. The technique is typically used with a standard, or reference stimulus, chosen as a good exemplar of "midrange" intelligibility. In several published studies, the standard has been chosen subjectively, usually on the basis of the expertise of the investigators. The current experiment demonstrates that a fixed set of sentence-level utterances, obtained from 4 individuals with dysarthria (2 with Parkinson disease, 2 with traumatic brain injury) as well as 3 neurologically normal speakers, is scaled differently depending on the identity of the standard. Four different standards were used in the main experiment, three of which were judged qualitatively in two independent evaluations to be good exemplars of midrange intelligibility. Acoustic analyses did not reveal obvious differences between these four standards but suggested that the standard with the worst-scaled intelligibility had much poorer voice source characteristics compared to the other three standards. Results are discussed in terms of possible standardization of midrange intelligibility exemplars for DME experiments.

  20. An orbit determination algorithm for small satellites based on the magnitude of the earth magnetic field

    Science.gov (United States)

    Zagorski, P.; Gallina, A.; Rachucki, J.; Moczala, B.; Zietek, S.; Uhl, T.

    2018-06-01

    Autonomous attitude determination systems based on simple measurements of vector quantities such as magnetic field and the Sun direction are commonly used in very small satellites. However, those systems always require knowledge of the satellite position. This information can be either propagated from orbital elements periodically uplinked from the ground station or measured onboard by dedicated global positioning system (GPS) receiver. The former solution sacrifices satellite autonomy while the latter requires additional sensors which may represent a significant part of mass, volume, and power budget in case of pico- or nanosatellites. Hence, it is thought that a system for onboard satellite position determination without resorting to GPS receivers would be useful. In this paper, a novel algorithm for determining the satellite orbit semimajor-axis is presented. The methods exploit only the magnitude of the Earth magnetic field recorded onboard by magnetometers. This represents the first step toward an extended algorithm that can determine all orbital elements of the satellite. The method is validated by numerical analysis and real magnetic field measurements.

  1. EXERCÍCIOS ENVOLVENDO A MAGNITUDE LIMITE NO ENSINO DE ASTRONOMIA

    Directory of Open Access Journals (Sweden)

    Lev Vertchenko

    Full Text Available Neste trabalho são apresentados alguns exercícios e atividades, elaborados para disciplinas de Astronomia Básica e inspirados na propos ta de exploração multicontextual de Ausubel, relacionando o conceito de magnitude limite ao poder de captação de luz de um instrumento ótico. Os resultados desses exercícios são comparados a contagens de estrelas, obtidas seja pela observação, a olho nu ou com instrumentos óticos, seja pelo uso de software do tipo carta celeste. O processo inclui a familiariza ção do estudante com o céu, com binóculos e telescópios e com vários softwares. São discutidas a relação dessas contagens com a distribuição espa cial das estrelas, e sua aplicabilidade a situações de ensino/aprendizagem.

  2. A spatial approach of magnitude-squared coherence applied to selective attention detection.

    Science.gov (United States)

    Bonato Felix, Leonardo; de Souza Ranaudo, Fernando; D'affonseca Netto, Aluizio; Ferreira Leite Miranda de Sá, Antonio Mauricio

    2014-05-30

    Auditory selective attention is the human ability of actively focusing in a certain sound stimulus while avoiding all other ones. This ability can be used, for example, in behavioral studies and brain-machine interface. In this work we developed an objective method - called Spatial Coherence - to detect the side where a subject is focusing attention to. This method takes into consideration the Magnitude Squared Coherence and the topographic distribution of responses among electroencephalogram electrodes. The individuals were stimulated with amplitude-modulated tones binaurally and were oriented to focus attention to only one of the stimuli. The results indicate a contralateral modulation of ASSR in the attention condition and are in agreement with prior studies. Furthermore, the best combination of electrodes led to a hit rate of 82% for 5.03 commands per minute. Using a similar paradigm, in a recent work, a maximum hit rate of 84.33% was achieved, but with a greater a classification time (20s, i.e. 3 commands per minute). It seems that Spatial Coherence is a useful technique for detecting focus of auditory selective attention. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Order of magnitude cost appraisal for selected aspects of clad waste management

    International Nuclear Information System (INIS)

    Zima, G.E.

    1977-02-01

    A simple formula, incorporating the fixed charge rate principle, is applied to a clad waste management exercise involving densification, canning, transportation and salt disposal. For the purpose of comparison with the bulk of published nuclear waste management costs, cost and fixed charge rate data appropriate to roughly the period 1970 to 1973 are used. Within the context of this order of magnitude appraisal, densification displays some cost advantage, reflected principally in the transportation cost. Dependent on the degree of densification, above a certain clad waste generation rate the transportation savings may be expected to exceed reasonable densification costs. There is no explicit consideration of the decontamination step in this appraisal. The limited accessibility of surface effect decontamination to internal transuranic and activation product contamination suggests a quite small influence of decontamination on the transportation and disposal costs. Decontamination may, however, have a significant effect on the ease of establishing a practicable containment envelope of high reliability throughout the clad waste history. A brief comparison is made of clad waste management costs with the major costs of the nuclear power economy. This comparison implies a virtually unlimited technical latitude for clad waste treatment in accommodating the public safety without significant perturbation of nuclear power costs. It is submitted that clad waste management optimization will be under the primal constraint of maximizing thelong term public safety, with economic analysis useful only as a discriminator between waste handling alternatives of sensibly equivalent containment qualities. Some areas of clad waste treatment meriting increased attention are noted

  4. Improving the segmentation of therapy-induced leukoencephalopathy using apriori information and a gradient magnitude threshold

    Science.gov (United States)

    Glass, John O.; Reddick, Wilburn E.; Reeves, Cara; Pui, Ching-Hon

    2004-05-01

    Reliably quantifying therapy-induced leukoencephalopathy in children treated for cancer is a challenging task due to its varying MR properties and similarity to normal tissues and imaging artifacts. T1, T2, PD, and FLAIR images were analyzed for a subset of 15 children from an institutional protocol for the treatment of acute lymphoblastic leukemia. Three different analysis techniques were compared to examine improvements in the segmentation accuracy of leukoencephalopathy versus manual tracings by two expert observers. The first technique utilized no apriori information and a white matter mask based on the segmentation of the first serial examination of each patient. MR images were then segmented with a Kohonen Self-Organizing Map. The other two techniques combine apriori maps from the ICBM atlas spatially normalized to each patient and resliced using SPM99 software. The apriori maps were included as input and a gradient magnitude threshold calculated on the FLAIR images was also utilized. The second technique used a 2-dimensional threshold, while the third algorithm utilized a 3-dimensional threshold. Kappa values were compared for the three techniques to each observer, and improvements were seen with each addition to the original algorithm (Observer 1: 0.651, 0.653, 0.744; Observer 2: 0.603, 0.615, 0.699).

  5. Does everyone have a price? On the role of payoff magnitude for ethical decision making.

    Science.gov (United States)

    Hilbig, Benjamin E; Thielmann, Isabel

    2017-06-01

    Most approaches to dishonest behavior emphasize the importance of corresponding payoffs, typically implying that dishonesty might increase with increasing incentives. However, prior evidence does not appear to confirm this intuition. However, extant findings are based on relatively small payoffs, the potential effects of which are solely analyzed across participants. In two experiments, we used different multi-trial die-rolling paradigms designed to investigate dishonesty at the individual level (i.e., within participants) and as a function of the payoffs at stake - implementing substantial incentives exceeding 100€. Results show that incentive sizes indeed matter for ethical decision making, though primarily for two subsets of "corruptible individuals" (who cheat more the more they are offered) and "small sinners" (who tend to cheat less as the potential payoffs increase). Others ("brazen liars") are willing to cheat for practically any non-zero incentive whereas still others ("honest individuals") do not cheat at all, even for large payoffs. By implication, the influence of payoff magnitude on ethical decision making is often obscured when analyzed across participants and with insufficiently tempting payoffs. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Quantitative trait loci for magnitude of the plasma cortisol response to confinement in rainbow trout.

    Science.gov (United States)

    Quillet, E; Krieg, F; Dechamp, N; Hervet, C; Bérard, A; Le Roy, P; Guyomard, R; Prunet, P; Pottinger, T G

    2014-04-01

    Better understanding of the mechanisms underlying interindividual variation in stress responses and their links with production traits is a key issue for sustainable animal breeding. In this study, we searched for quantitative trait loci (QTL) controlling the magnitude of the plasma cortisol stress response and compared them to body size traits in five F2 full-sib families issued from two rainbow trout lines divergently selected for high or low post-confinement plasma cortisol level. Approximately 1000 F2 individuals were individually tagged and exposed to two successive acute confinement challenges (1 month interval). Post-stress plasma cortisol concentrations were determined for each fish. A medium density genome scan was carried out (268 markers, overall marker spacing less than 10 cM). QTL detection was performed using qtlmap software, based on an interval mapping method (http://www.inra.fr/qtlmap). Overall, QTL of medium individual effects on cortisol responsiveness (confinement stressor are distinct traits sharing only part of their genetic control. Chromosomal location of the steroidogenic acute regulatory protein (STAR) makes it a good potential candidate gene for one of the QTL. Finally, comparison of body size traits QTL (weight, length and body conformation) with cortisol-associated QTL did not support evidence for negative genetic relationships between the two types of traits. © 2014 Stichting International Foundation for Animal Genetics.

  7. Two way assessment of other physical work demands while measuring the whole body vibration magnitude

    Science.gov (United States)

    Tiemessen, Ivo J. H.; Hulshof, Carel T. J.; Frings-Dresen, Monique H. W.

    2008-03-01

    Direct observation, instead of using self-administered questionnaires might give more reliable and specific information about physical work demands at the workplace. This information is of use in a population already at risk of developing low back pain (LBP) due to whole body vibration (WBV) exposure. The aims of this study are to assess the WBV exposure in an exposed population and to assess other physical work demands in two ways, by direct observation and with the use of a self-administered questionnaire. We therefore assessed the WBV magnitude and 5 WBV-related physical work demands by using the PalmTrac system and a self-administered questionnaire in a group of drivers ( N=10). The main findings are 7 out of 10 drivers are exceeding the EU action value. About 50% of the drivers under-estimated the time 'bending', 60% the time 'walking+standing' and 60% over-estimated the time when 'lifting.' We concluded that 7 drivers from this group are at risk of developing LBP and substantial differences exists for the 5 physical work demands comparing the PalmTrac method with the questionnaire. Direct observational assessment in WBV measurements yields extra information. This is useful for preventive activities necessary as drivers are exceeding the EU action value.

  8. Magnitude of Maternal Anaemia in Rural Burkina Faso: Contribution of Nutritional Factors and Infectious Diseases

    Directory of Open Access Journals (Sweden)

    Nicolas Meda

    2016-01-01

    Full Text Available Background. Maternal anaemia is a worldwide public health problem affecting particularly developing countries. In Burkina Faso, little data is available for rural areas. This study aimed to determine the prevalence of maternal anaemia and the risk factors associated with it in the rural health district of Hounde in Burkina Faso but also to define better control measures of maternal anaemia. Methods. This cross-sectional study conducted in 2010 had a sample of 3,140 pregnant women attending antenatal care in all the 18 primary health care facilities of the district. The women’s characteristics and their knowledge about contraceptives and sexually transmitted infections (STI were collected. Also, physical and gynaecological examination, completed by vaginal, cervix, blood, and stool samplings, were collected. Results. A prevalence of 63.1% was recorded for maternal anaemia. Geophagy rate was 16.3% and vitamin A deficiency 69.3%. In addition, anaemia was independently associated with low education, low brachial perimeter, geophagy, and primigravida. But no statically significant relationship was found between maternal anaemia and infectious diseases or vitamin A deficiency. Conclusion. The magnitude of maternal anaemia was found to be higher in rural Hounde health district and should be addressed by adequate policy including education and the fight against malnutrition.

  9. Synthetic Jet Interactions with Flows of Varying Separation Severity and Spanwise Flow Magnitude

    Science.gov (United States)

    Monastero, Marianne; Lindstrom, Annika; Amitay, Michael

    2017-11-01

    Flow physics associated with the interactions of synthetic jet actuators with a highly three-dimensional separated flow over a flapped airfoil were investigated experimentally and analyzed using stereo particle image velocimetry (SPIV) and surface pressure data. Increased understanding of active flow control devices in flows which are representative of airplane wings or tails can lead to actuator placement (i.e., chordwise location, spanwise spacing) with the greatest beneficial effect on performance. An array of discrete synthetic jets was located just upstream of the control surface hingeline and operated at a blowing ratio of 1 and non-dimensional frequency of 48. Detailed flowfield measurements over the control surface were conducted, where the airfoil's sweep angle and the control surface deflection angle were fixed at 20°. Focus was placed on the local and global flowfields as spanwise actuator spacing was varied. Moreover, surface pressure measurement for several sweep angles, control surface deflection angles, and angles of attack were also performed. Actuation resulted in an overall separation reduction and a dependence of local flowfield details (i.e. separation severity, spanwise flow magnitude, flow structures, and jet trajectory) on spanwise jet spacing. The Boeing Company.

  10. Calculated dependence of FePt damping on external field magnitude and direction

    Directory of Open Access Journals (Sweden)

    N. A. Natekar

    2017-05-01

    Full Text Available Near the Curie temperature (Tc, magnetic parameters including magnetization, anisotropy, and damping depend strongly on both temperature and length scale. This manifestation of renormalization theory is most readily seen in the case of magnetization where the magnitude of the atomic spin is largely unaffected by temperature, but the bulk magnetization vanishes at Tc. It has been previously argued that the Landau-Lifshitz-Gilbert damping parameter alpha exhibits a similar effect owing to its dependence on both atomic effects and magnon-magnon scattering, the latter having a strong length dependence. Here, we calculate, using an anisotropic exchange description of L10 FePt (Tc = 705 K, the damping (and other magnetic properties dependence on temperature for FePt at length scales around 1.0 nm as appropriate for high temperature micromagnetic simulation. While the damping reduces as the applied field along the easy direction increases, it tends to increase as the field direction is changed to in-plane. The renormalized parameters are also calculated for higher and lower Tc (770K and 630K by invoking the linear relationship between the exchange stiffness parameter and Curie temperature. This corresponds to doped and/or non-stoichiometric FePt and allows better understanding of the effects of varying anisotropy to exchange ratio.

  11. The impact of a high magnitude flood on metal pollution in a shallow subtropical estuarine embayment.

    Science.gov (United States)

    Coates-Marnane, J; Olley, J; Burton, J; Grinham, A

    2016-11-01

    Drought-breaking floods pose a risk to coastal water quality as sediments, nutrients, and pollutants stored within catchments during periods of low flow are mobilized and delivered to coastal waters within a short period of time. Here we use subtidal surface sediment surveys and sediment cores to explore the effects of the 2011 Brisbane River flood on trace metals zinc (Zn), lead (Pb), copper (Cu), nickel (Ni), chromium (Cr), manganese (Mn), and phosphorus (P) deposition in Moreton Bay, a shallow subtropical bay in eastern Australia. Concentrations of Zn, Cu, and Pb in sediments in central Moreton Bay derived from the 2011 flood were the highest yet observed in the Bay. We suggest flushing of metal rich sediments which had accumulated on the Brisbane River floodplain and in its estuary during the preceding 10 to 40years of low flows to be the primary source of this increase. This highlights the importance of intermittent high magnitude floods in tidally influenced rivers in controlling metal transport to coastal waters in subtropical regions. Copyright © 2016. Published by Elsevier B.V.

  12. The magnitude and timing of grandparental coresidence during childhood in the United States

    Directory of Open Access Journals (Sweden)

    Mariana Amorim

    2017-12-01

    Full Text Available Background: The likelihood that a US child will live with a grandparent has increased over time. In 2015, nearly 12Š of children lived with a grandparent. However, the likelihood that a child will ever live with a grandparent is not known. Objective: We calculate the cumulative and age-specific probabilities of coresidence with grandparents during childhood. We stratify our analyses by types of grandparent-grandchild living arrangements (grandfamilies and three-generation households and by race and ethnicity. Methods: We use two data sets - the pooled 2010-2015 American Community Surveys (ACS and the 1997 National Longitudinal Survey of Youth (NLSY-97 - and produce estimates using life tables techniques. Results: Results indicate that nearly 30Š of US children ever coreside with grandparents. Both three-generation and grandfamily living arrangements are more prevalent among racial and ethnic minority groups, with three-generation coresidence particularly common among Asian children. Black children are nearly two times as likely to ever live in a grandfamily as compared to Hispanic and white children, respectively. Children are much more likely to experience grandparental coresidence during their first year of life than in any other year. Conclusions: This paper suggests that the magnitude of grandparental coresidence is greater than previously known, particularly in early childhood. Contribution: This is the first study to calculate age-specific and cumulative probabilities of coresidence with grandparents during the whole childhood. Doing so allows us to better craft public policies and guide new research on family complexity.

  13. Total magnitude of diffusion tensor imaging as an effective tool for the differentiation of glioma

    Energy Technology Data Exchange (ETDEWEB)

    Smitha, Karavallil A., E-mail: mithamahesh@gmail.com [Department of Imaging Sciences and Interventional Radiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram (India); Gupta, Arun kumar, E-mail: gupta209@gmail.com [Department of Neuroimaging and Interventional Radiology, National Institute of Mental Health and Neuro Sciences, Bangalore (India); Jayasree, Ramapurath S., E-mail: jayashreemenon@gmail.com [Biophotonics and Imaging Laboratory, Biomedical Technology Wing, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram (India)

    2013-05-15

    Objectives: The study aims to evaluate the difference in diffusion properties between high grade glioma and low grade glioma by measuring the total magnitude of diffusion tensor (L), and its isotropic (p) and anisotropic (q) components. Methods: The diffusion tensor parameters p, q, L and FA from the tumor area, adjacent area to the tumor and corresponding contra lateral normal area of 30 high grade glioma and 49 low grade glioma were calculated. Chi square analysis was done to find the changes in age and sex. One Way ANOVA was performed to compare the mean and ROC curve analysis to confirm the discriminative sensitivity. Results: Major variation in the mean values of p, L and FA was observed in different brain areas considered. Variation in the p and L values between low grade and high grade glioma were statistically significant (p < 0.001) and their ROC curve analysis yielded 93.9% and 91.8% sensitivity and 53.3% specificity respectively. Conclusion: Measurement of the isotropic component p and the total value of diffusion tensor L can be effectively correlated with different grades of glioma and can be used to study the diffusion properties of tumor affected brain.

  14. Large magnitude gridded ionization chamber for impurity identification in alpha emitting radioactive samples

    International Nuclear Information System (INIS)

    Santos, R.N. dos.

    1992-01-01

    This paper refers to a large magnitude gridded ionization chamber with high resolution used in the identification of α radioactive samples. The chamber and the electrode have been described in terms of their geometry and dimensions, as well as the best results listed accordingly. Several α emitting radioactive samples were used with a gas mixture of 90% Argon plus 10% Methane. We got α energy spectrum with resolution around 22,14 KeV in agreement to the best results available in the literature. The spectrum of α energy related to 92 U 233 was gotten using the ionization chamber mentioned in this work; several values were found which matched perfectly well adjustment curve of the chamber. Many other additional measures using different kinds of adjusted detectors were successfully obtained in order to confirm the results gotten in the experiments, thus leading to the identification of some elements of the 92 U 233 radioactive series. Such results show the possibility of using the chamber mentioned for measurements of α low activity contamination. (author)

  15. [Homicides in the Americas region: magnitude, distribution and trends, 1999-2009].

    Science.gov (United States)

    Gawryszewski, Vilma Pinheiro; Sanhueza, Antonio; Martinez-Piedra, Ramon; Escamilla, José Antonio; de Souza, Maria de Fátima Marinho

    2012-12-01

    The scope of this study was to describe the magnitude and distribution of deaths by homicide in the Americas and to analyze the prevailing trends. Deaths by homicide (X85 to Y09 and Y35) were analyzed in 32 countries of the Americas Region from 1999 to 2009, recorded in the Mortality Information System/Pan American Health Organization. A negative binomial model was used to study the trends. There were around 121,297 homicides (89% men and 11% women) in the Americas, annually, predominantly in the 15 to 24 and 25 to 39 year age brackets. In 2009 the homicide age-adjusted mortality rate was 15.5/100,000 in the region. Countries with lower rates/100,000 were Canada (1.8), Argentina (4.4), Cuba (4.8), Chile (5.2), and the United States (5.8), whereas the highest rates/100,000 were in El Salvador (62.9), Guatemala (51.2), Colombia (42.5), Venezuela (33.2), and Puerto Rico (25.8). From 1999-2009, the homicide trend in the region was stable. They increased in nine countries: Venezuela (phomicide rates and they are on the increase.

  16. Improved olefinic fat suppression in skeletal muscle DTI using a magnitude-based dixon method.

    Science.gov (United States)

    Burakiewicz, Jedrzej; Hooijmans, Melissa T; Webb, Andrew G; Verschuuren, Jan J G M; Niks, Erik H; Kan, Hermien E

    2018-01-01

    To develop a method of suppressing the multi-resonance fat signal in diffusion-weighted imaging of skeletal muscle. This is particularly important when imaging patients with muscular dystrophies, a group of diseases which cause gradual replacement of muscle tissue by fat. The signal from the olefinic fat peak at 5.3 ppm can significantly confound diffusion-tensor imaging measurements. Dixon olefinic fat suppression (DOFS), a magnitude-based chemical-shift-based method of suppressing the olefinic peak, is proposed. It is verified in vivo by performing diffusion tensor imaging (DTI)-based quantification in the lower leg of seven healthy volunteers, and compared to two previously described fat-suppression techniques in regions with and without fat contamination. In the region without fat contamination, DOFS produces similar results to existing techniques, whereas in muscle contaminated by subcutaneous fat signal moved due to the chemical shift artefact, it consistently showed significantly higher (P = 0.018) mean diffusivity (MD). Because fat presence lowers MD, this suggests improved fat suppression. DOFS offers superior fat suppression and enhances quantitative measurements in the muscle in the presence of fat. DOFS is an alternative to spectral olefinic fat suppression. Magn Reson Med 79:152-159, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  17. Order of magnitude smaller limit on the electric dipole moment of the electron.

    Science.gov (United States)

    Baron, J; Campbell, W C; DeMille, D; Doyle, J M; Gabrielse, G; Gurevich, Y V; Hess, P W; Hutzler, N R; Kirilov, E; Kozyryev, I; O'Leary, B R; Panda, C D; Parsons, M F; Petrik, E S; Spaun, B; Vutha, A C; West, A D

    2014-01-17

    The Standard Model of particle physics is known to be incomplete. Extensions to the Standard Model, such as weak-scale supersymmetry, posit the existence of new particles and interactions that are asymmetric under time reversal (T) and nearly always predict a small yet potentially measurable electron electric dipole moment (EDM), d(e), in the range of 10(-27) to 10(-30) e·cm. The EDM is an asymmetric charge distribution along the electron spin (S(→)) that is also asymmetric under T. Using the polar molecule thorium monoxide, we measured d(e) = (-2.1 ± 3.7stat ± 2.5syst) × 10(-29) e·cm. This corresponds to an upper limit of |d(e)| < 8.7 × 10(-29) e·cm with 90% confidence, an order of magnitude improvement in sensitivity relative to the previous best limit. Our result constrains T-violating physics at the TeV energy scale.

  18. Assessment of the magnitude of ammonia emissions in the United Kingdom

    Science.gov (United States)

    Sutton, M. A.; Place, C. J.; Eager, M.; Fowler, D.; Smith, R. I.

    Estimates of ammonia emission in the U.K. have been critically reviewed with the aim of establishing the magnitude and uncertainty of each of the sources. European studies are also reviewed, with the U.K. providing a useful case study to highlight the uncertainties common to all ammonia emission inventories. This analysis of the emission factors and their application to U.K. sources supports an emission of 450 (231-715) Gg NH 3 yr -1. Agricultural activities are confirmed as the major source, providing 406 (215-630) Gg NH 3yr -1 (90% of the total), and therefore dominate uncertainties. Non-agricultural sources include sewage, pets, horses, humans, combustion and wild animals, though these contribute only 44 (16-85) Gg yr -1. Cattle represent the largest single uncertainty, accounting for 245 (119-389) Gg yr -1. The major uncertainties for cattle derive from estimation of the amount of nitrogen (N) excreted, the % N volatilized from land spreading of wastes, and the % N volatilized from stored farm-yard manure. Similar relative uncertainties apply to each of sheep, pigs and poultry, as well as fertilized crops, though these are quantitatively less important. Accounting; for regional differences in livestock demography, emission of 347, 63 and 40 Gg yr -1 are estimated for England & Wales, Scotland, and Northern Ireland, respectively. Though very uncertain, the total is in good agreement with estimates required to balance the U.K. atmospheric NH. budget.

  19. IDC Reengineering Phase 2 & 3 Rough Order of Magnitude (ROM) Cost Estimate Summary (Leveraged NDC Case).

    Energy Technology Data Exchange (ETDEWEB)

    Harris, James M.; Prescott, Ryan; Dawson, Jericah M.; Huelskamp, Robert M.

    2014-11-01

    Sandia National Laboratories has prepared a ROM cost estimate for budgetary planning for the IDC Reengineering Phase 2 & 3 effort, based on leveraging a fully funded, Sandia executed NDC Modernization project. This report provides the ROM cost estimate and describes the methodology, assumptions, and cost model details used to create the ROM cost estimate. ROM Cost Estimate Disclaimer Contained herein is a Rough Order of Magnitude (ROM) cost estimate that has been provided to enable initial planning for this proposed project. This ROM cost estimate is submitted to facilitate informal discussions in relation to this project and is NOT intended to commit Sandia National Laboratories (Sandia) or its resources. Furthermore, as a Federally Funded Research and Development Center (FFRDC), Sandia must be compliant with the Anti-Deficiency Act and operate on a full-cost recovery basis. Therefore, while Sandia, in conjunction with the Sponsor, will use best judgment to execute work and to address the highest risks and most important issues in order to effectively manage within cost constraints, this ROM estimate and any subsequent approved cost estimates are on a 'full-cost recovery' basis. Thus, work can neither commence nor continue unless adequate funding has been accepted and certified by DOE.

  20. Combining Earthquake Focal Mechanism Inversion and Coulomb Friction Law to Yield Tectonic Stress Magnitudes in Strike-slip Faulting Regime

    Science.gov (United States)

    Soh, I.; Chang, C.

    2017-12-01

    The techniques for estimating present-day stress states by inverting multiple earthquake focal mechanism solutions (FMS) provide orientations of the three principal stresses and their relative magnitudes. In order to estimate absolute magnitudes of the stresses that are generally required to analyze faulting mechanics, we combine the relative stress magnitude parameter (R-value) derived from the inversion process and the concept of frictional equilibrium of stress state defined by Coulomb friction law. The stress inversion in Korean Peninsula using 152 FMS data (magnitude≥2.5) conducted at regularly spaced grid points yields a consistent strike-slip faulting regime in which the maximum (S1) and the minimum (S3) principal stresses act in horizontal planes (with an S1 azimuth in ENE-WSW) and the intermediate principal stress (S2) close to vertical. However, R-value varies from 0.28 to 0.75 depending on locations, systematically increasing eastward. Based on the assumptions that the vertical stress is lithostatic, pore pressure is hydrostatic, and the maximum differential stress (S1-S3) is limited by Byerlee's friction of optimally oriented faults for slip, we estimate absolute magnitudes of the two horizontal principal stresses using R-value. As R-value increases, so do the magnitudes of the horizontal stresses. Our estimation of the stress magnitudes shows that the maximum horizontal principal stress (S1) normalized by vertical stress tends to increase from 1.3 in the west to 1.8 in the east. The estimated variation of stress magnitudes is compatible with distinct clustering of faulting types in different regions. Normal faulting events are densely populated in the west region where the horizontal stress is relatively low, whereas numerous reverse faulting events prevail in the east offshore where the horizontal stress is relatively high. Such a characteristic distribution of distinct faulting types in different regions can only be explained in terms of stress