WorldWideScience

Sample records for density irregularities diagnosed

  1. Rocket measurements of electron density irregularities during MAC/SINE

    Science.gov (United States)

    Ulwick, J. C.

    1989-01-01

    Four Super Arcas rockets were launched at the Andoya Rocket Range, Norway, as part of the MAC/SINE campaign to measure electron density irregularities with high spatial resolution in the cold summer polar mesosphere. They were launched as part of two salvos: the turbulent/gravity wave salvo (3 rockets) and the EISCAT/SOUSY radar salvo (one rocket). In both salvos meteorological rockets, measuring temperature and winds, were also launched and the SOUSY radar, located near the launch site, measured mesospheric turbulence. Electron density irregularities and strong gradients were measured by the rocket probes in the region of most intense backscatter observed by the radar. The electron density profiles (8 to 4 on ascent and 4 on descent) show very different characteristics in the peak scattering region and show marked spatial and temporal variability. These data are intercompared and discussed.

  2. Measurements of electron density irregularities in the ionosphere of Jupiter by Pioneer 10

    International Nuclear Information System (INIS)

    Woo, R.; Yang, F.

    1976-01-01

    In this paper we demonstrate that when the frequency spectrum of the log amplitude fluctuations is used, the radio occultation experiment is a powerful tool for detecting, identifying, and studying ionospheric irregularities. Analysis of the Pioneer 10 radio occultation measurements reveals that the Jovian ionosphere possesses electron density irregularities which are very similar to those found in the earth's ionosphere. This is the first time such irregularities have been found in a planetary ionosphere other than that of earth. The Pioneer 10 results indicate that the spatial wave number spectrum of the electron density irregularities is close to the Kolmogorov spectrum and that the outer scale size is greater than the Fresnel size (6.15 km). This type of spectrum suggests that the irregularities are probably produced by the turbulent dissipation of irregularities larger than the outer scale size

  3. Spectral classification of medium-scale high-latitude F region plasma density irregularities

    International Nuclear Information System (INIS)

    Singh, M.; Rodriguez, P.; Szuszczewicz, E.P.; Sachs Freeman Associates, Bowie, MD)

    1985-01-01

    The high-latitude ionosphere represents a highly structured plasma. Rodriguez and Szuszczewicz (1984) reported a wide range of plasma density irregularities (150 km to 75 m) at high latitudes near 200 km. They have shown that the small-scale irregularities (7.5 km to 75 m) populated the dayside oval more often than the other phenomenological regions. It was suggested that in the lower F region the chemical recombination is fast enough to remove small-scale irregularities before convection can transport them large distances, leaving structured particle precipitation as the dominant source term for irregularities. The present paper provides the results of spectral analyses of pulsed plasma probe data collected in situ aboard the STP/S3-4 satellite during the period March-September 1978. A quantitative description of irregularity spectra in the high-latitude lower F region plasma density is given. 22 references

  4. Study of electromagnetic wave scattering by periodic density irregularities in plasma

    International Nuclear Information System (INIS)

    Lyle, R.; Kuo, S.P.; Huang, J.

    1995-01-01

    A quasi-particle approach is used to formulate wave propagation and scattering in a periodically structured plasma. The theory is then applied to study the effect of bottomside sinusoidal (BSS) irregularities on the propagation of beacon satellites signals through the ionosphere. In this approach, the radio wave is treated as a distribution of quasi-particles described by a Wigner distribution function governed by a transport equation. The irregularities providing the collisional effect are modeled as a two dimensional density modulation on a uniform background plasma. The present work generalizes the previous work by including the spectral bandwidth (Δk/k) effect of the spatially periodic irregularities on the transionospheric signal propagation. The collision of quasi-particles with the irregularities modifies the quasi-particle distribution and give rise to the wave scattering phenomenon. The multiple scattering process is generally considered in this deterministic analysis of radio wave scattering off the ionospheric density irregularities. The analysis shows that this two dimensional density grating effectively modulates the intensity of the beacon satellite signals. This spatial modulation of the wave intensity is converted into time modulation due to the drift of the ionospheric irregularities, which then results in the scintillation of the beacon satellite signals

  5. Some new features of electron density irregularities over SHAR during strong spread F

    Directory of Open Access Journals (Sweden)

    S. Raizada

    Full Text Available An RH-560 rocket flight was conducted from Sriharikota rocket range (SHAR (14°N, 80°E, dip latitude 5.5°N to study electron density and electric field irregularities during spread F. The rocket was launched at 2130 local time (LT and it attained an apogee of 348 km. Results of electron density fluctuations are presented here. Two extremely sharp layers of very high electron density were observed at 105 and 130 km. The electron density increase in these layers was by a factor of 50 in a vertical extent of 10 km. Large depletions in electron density were observed around 175 and 238 km. Both sharp layers as well as depletions were observed also during the descent. The presence of sharp layers and depletions during the ascent and the descent of the rocket as well as an order of magnitude less electron density, in 150-300 km region during the descent, indicate the presence of strong large-scale horizontal gradients in the electron density. Some of the valley region irregularities (165-178 km, in the intermediate scale size range, observed during this flight, show spectral peaks at 2 km and can be interpreted in terms of the image striation theory suggested by Vickrey et al. The irregularities at 176 km do not exhibit any peak at kilometer scales and appear to be of new type. The growth rate of intermediate scale size irregularities, produced through generalized Rayleigh Taylor instability, was calculated for the 200-330 km altitude, using observed values of electron density gradients and an assumed vertically downward wind of 20 ms-1. These growth rate calculations suggest that the observed irregularities could be produced by the gradient drift instability.

    Key words: Ionosphere (equatorial ionosphere; ionospheric irregularities - Radio science (ionospheric physics

  6. Some new features of electron density irregularities over SHAR during strong spread F

    Directory of Open Access Journals (Sweden)

    S. Raizada

    2000-02-01

    Full Text Available An RH-560 rocket flight was conducted from Sriharikota rocket range (SHAR (14°N, 80°E, dip latitude 5.5°N to study electron density and electric field irregularities during spread F. The rocket was launched at 2130 local time (LT and it attained an apogee of 348 km. Results of electron density fluctuations are presented here. Two extremely sharp layers of very high electron density were observed at 105 and 130 km. The electron density increase in these layers was by a factor of 50 in a vertical extent of 10 km. Large depletions in electron density were observed around 175 and 238 km. Both sharp layers as well as depletions were observed also during the descent. The presence of sharp layers and depletions during the ascent and the descent of the rocket as well as an order of magnitude less electron density, in 150-300 km region during the descent, indicate the presence of strong large-scale horizontal gradients in the electron density. Some of the valley region irregularities (165-178 km, in the intermediate scale size range, observed during this flight, show spectral peaks at 2 km and can be interpreted in terms of the image striation theory suggested by Vickrey et al. The irregularities at 176 km do not exhibit any peak at kilometer scales and appear to be of new type. The growth rate of intermediate scale size irregularities, produced through generalized Rayleigh Taylor instability, was calculated for the 200-330 km altitude, using observed values of electron density gradients and an assumed vertically downward wind of 20 ms-1. These growth rate calculations suggest that the observed irregularities could be produced by the gradient drift instability.Key words: Ionosphere (equatorial ionosphere; ionospheric irregularities - Radio science (ionospheric physics

  7. Application of digital tomosynthesis in diagnosing the fractures or dislocations in irregular bones and regions with complex structures.

    Science.gov (United States)

    Tuerdi, Batuer; Wang, Hui; Zhang, Ying; Zhou, Hao; Zhang, Hao

    2015-01-01

    The application potential of digital tomosynthesis in diagnosing fractures or dislocations in irregular bones and regions with complex structures was evaluated. Digital radiography and tomosynthesis were performed in 121 patients, and the image quality, accuracy, sensitivity, and specificity were compared. The number of participants with a definite diagnosis of fracture and/or dislocation was 98. The ratio of excellent images, accuracy, sensitivity, and specificity of digital tomosynthesis were higher than that of direct radiography. Digital tomosynthesis could be applied in the diagnosis of fractures or dislocations in irregular bones and regions with complex structures. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Characterization of the low latitude plasma density irregularities observed using C/NOFS and SCINDA data

    Science.gov (United States)

    Andima, Geoffrey; Amabayo, Emirant B.; Jurua, Edward; Cilliers, Pierre J.

    2018-01-01

    Complex electrodynamic processes over the low latitude region often result in post sunset plasma density irregularities which degrade satellite communication and navigation. In order to forecast the density irregularities, their occurrence time, duration and location need to be quantified. Data from the Communication/Navigation Outage Forecasting System (C/NOFS) satellite was used to characterize the low latitude ion density irregularities from 2011 to 2013. This was supported by ground based data from the SCIntillation Network Decision Aid (SCINDA) receivers at Makerere (Geographic coordinate 32.6°E, 0.3°N, and dip latitude -9.3°N) and Nairobi (Geographic coordinate 36.8°E, -1.3°N, and dip latitude -10.8°N). The results show that irregularities in ion density have a daily pattern with peaks from 20:00 to 24:00 Local Time (LT). Scintillation activity at L band and VHF over East Africa peaked in 2011 and 2012 from 20:00 to 24:00 LT, though in many cases scintillation at VHF persisted longer than that at L band. A longitudinal pattern in ion density irregularity occurrence was observed with peaks over 135-180°E and 270-300°E. The likelihood of ion density irregularity occurrence decreased with increasing altitude. Analysis of C/NOFS zonal ion drift velocities showed that the largest nighttime and daytime drifts were in 270-300°E and 300-330°E longitude regions respectively. Zonal irregularity drift velocities over East Africa were for the first time estimated from L-band scintillation indices. The results show that the velocity of plasma density irregularities in 2011 and 2012 varied daily, and hourly in the range of 50-150 m s-1. The zonal drift velocity estimates from the L-band scintillation indices had good positive correlation with the zonal drift velocities derived from VHF receivers by the spaced receiver technique.

  9. Analysis of Mid-Latitude Plasma Density Irregularities in the Presence of Finite Larmor Radius Effects

    Science.gov (United States)

    Sotnikov, V. I.; Kim, T. C.; Mishin, E. V.; Kil, H.; Kwak, Y. S.; Paraschiv, I.

    2017-12-01

    Ionospheric irregularities cause scintillations of electromagnetic signals that can severely affect navigation and transionospheric communication, in particular during space storms. At mid-latitudes the source of F-region Field Aligned Irregularities (FAI) is yet to be determined. They can be created in enhanced subauroral flow channels (SAI/SUBS), where strong gradients of electric field, density and plasma temperature are present. Another important source of FAI is connected with Medium-scale travelling ionospheric disturbances (MSTIDs). Related shear flows and plasma density troughs point to interchange and Kelvin-Helmholtz type instabilities as a possible source of plasma irregularities. A model of nonlinear development of these instabilities based on the two-fluid hydrodynamic description with inclusion of finite Larmor radius effects will be presented. This approach allows to resolve density irregularities on the meter scale. A numerical code in C language to solve the derived nonlinear equations for analysis of interchange and flow velocity shear instabilities in the ionosphere was developed. This code will be used to analyze competition between interchange and Kelvin-Helmholtz instabilities in the mid-latitude region. The high-resolution simulations with continuous density and velocity profiles will be driven by the ambient conditions corresponding to the in situ data obtained during the 2016 Daejeon (Korea) and MU (Japan) radar campaign and data collected simultaneously by the Swarm satellites passed over Korea and Japan. PA approved #: 88ABW-2017-3641

  10. Rocket observation of electron density irregularities in the lower E region

    International Nuclear Information System (INIS)

    Watanabe, Yuzo; Nakamura, Yoshiharu; Amemiya, Hiroshi.

    1990-01-01

    Local ionospheric electron density irregularities in the scale size of 3 m to 300 m have been measured on the ascending path from 74 km to 93 km by a fix biased Langmuir probe on board the S-310-16 sounding rocket. The rocket was launched at 22:40:00 on February 1, 1986 from Kagoshima Space Center in Japan. It is found from frequency analysis of the data that the spectral index of the irregularities is 0.9 to 1.8 and the irregularity amplitude is 1 to 15 %. The altitude where the amplitude reaches its maximum is 88 km. The generation mechanism of these irregularities is explained by the neutral turbulence theory, which indicates that the spectral index is 5/3 and has been confirmed by a chemical release experiment using rockets over India to be valid up to about 110 km. From frequency analysis of the data observed during the descent in the lower E region, we have found that the rocket-wake effect becomes larger when the probe is situated near the edge of the rocket-wake, and that this is also the case even when the rocket-wake effect does not clearly appear in the DC current signal which approximately changes in proportion to the electron density, where the probe is completely situated inside the rocket-wake region. (author)

  11. The structure of plasma-density irregularities in the interplanetary medium

    International Nuclear Information System (INIS)

    Singleton, D.G.

    1975-01-01

    The conflict in the literature as to whether the plasma-density spatial spectrum of the irregularities in the interplanetary medium is of Gaussian or power law form is discussed. Particular attention is paid to the interplanetary scintillation effects ascribed to these irregularities. It is shown that the phase-screen theory of scintillations can be invoked to devise a set of critical tests which provide a means of discriminating between the conflicting hypotheses. Differences in the predicted behaviour of the single sensor temporal spectra of the scintillations for the two irregularity forms provide the main tests of the conflicting hypotheses. However, it is also shown that the two hypotheses lead to different forms of the variation of scintillation index with the observing frequency and the solar elongation of the scintillating source. Consideration is given to the optimum conditions for observing the Fourier and Bessel temporal spectra modulation which is due to the Fresnel filtering of the spatial spectrum. Determination of irregularity shape, orientation and motion in terms of this modulation is also discussed. (author)

  12. F region electron density irregularity spectra near Auroral acceleration and shear regions

    International Nuclear Information System (INIS)

    Basu, S.; Basu, S.; MacKenzie, E.; Coley, W.R.; Hanson, W.B.; Lin, C.S.

    1984-01-01

    Spectral characteristics of auroral F region irregularities were studied by the use of high-resolution (approx.35 m) density measurements made by the retarding potential analyzer (RPA) on board the Atmosphere Explorer D (AE-D) satellite during two orbits when the satellite was traversing the high-latitude ionosphere in the evening sector. Coordinated DMSP passes provided synoptic coverage of auroral activity. The auroral energy input was estimated by intergrating the low-energy electron (LEE) data on AE-D. It was found that the one-dimensional in situ spectral index (p 1 ) of the irregularities at scale lengths of 1 values of approx.-3. This is interpreted as resulting from the effects of E region conductivity on the F region irregularity structure. The regions in between the precipitation structures, where presumably the E region conductivity was small, were generally associated with large shears in the horizontal E-W drifts and large velocities, as measured by the ion drift meter on board AE-D. The maximum drifts measured were approx.2 km s -1 , corresponding to an electric field of 100 mV m -1 . The large-velocity regions were also associated with substantial ion heating and electron density depletions. The largest shear magnitudes observed were approx.80 m s -1 km -1 , and the shear gradient scale lengths were approx.10 km, which was approximately the resolution of the ion drift meter data set used. The spectral characteristics of irregularities in the large, variable flow regions were very different, with p 1 being approx.-1

  13. Optimized Irregular Low-Density Parity-Check Codes for Multicarrier Modulations over Frequency-Selective Channels

    Directory of Open Access Journals (Sweden)

    Valérian Mannoni

    2004-09-01

    Full Text Available This paper deals with optimized channel coding for OFDM transmissions (COFDM over frequency-selective channels using irregular low-density parity-check (LDPC codes. Firstly, we introduce a new characterization of the LDPC code irregularity called “irregularity profile.” Then, using this parameterization, we derive a new criterion based on the minimization of the transmission bit error probability to design an irregular LDPC code suited to the frequency selectivity of the channel. The optimization of this criterion is done using the Gaussian approximation technique. Simulations illustrate the good performance of our approach for different transmission channels.

  14. Electrostatic lower hybrid waves excited by electromagnetic whistler mode waves scattering from planar magnetic-field-aligned plasma density irregularities

    International Nuclear Information System (INIS)

    Bell, T.F.; Ngo, H.D.

    1990-01-01

    Recent satellite observations demonstrate that high amplitude, short wavelength (5 m ≤ λ ≤ 100 m) electrostatic waves are commonly excited by electromagnetic whistler mode waves propagating in regions of the magnetosphere and topside ionosphere where small-scale magnetic-field-aligned plasma density irregularities are thought to exist. A new theoretical model of this phenomenon is presented, based upon passive linear scattering in a cold magnetoplasma. In this model the electrostatic waves are excited by linear mode coupling as the incident electromagnetic whistler mode waves scatter from the magnetic-field-aligned plasma density irregularities. The excited short wavelength waves are quasi-electrostatic whistler mode waves, a type of lower hybrid wave, whose wave normal lies near the whistler mode resonance cone where the wave refractive index becomes very large. The amplitude of the excited electrostatic lower hybrid waves is calculated for a wide range of values of input electromagnetic wave frequency, wave normal direction, electron plasma frequency, gyrofrequency, ion composition, and irregularity scale and density enhancement. Results indicate that high amplitude lower hybrid waves can be excited over a wide range of parameters for irregularity density enhancements as low as 5% whenever the scale of the irregularity is of the same order as the lower hybrid wavelength

  15. Energetic efficiency, menstrual irregularity, and bone mineral density in elite professional female ballet dancers.

    Science.gov (United States)

    Doyle-Lucas, Ashley F; Akers, Jeremy D; Davy, Brenda M

    2010-01-01

    Sports that emphasize low body weight for optimal performance, such as ballet, are associated with an increased prevalence of the female athlete triad (FT). Previous research in this area that involves dancers has been limited; the majority of studies have been performed on adolescents training in classical ballet, and not professional adult dancers. The purpose of this study is to compare the physical and behavioral characteristics of female elite ballet dancers to sedentary, recreationally active non-dancing controls, with regard to characteristics of the FT and energetic efficiency. Women aged 18 to 35 years were recruited as participants. The dancers (N = 15) and non-dancing controls (N = 15) were pair-matched via age (dancers: 24.3 ± 1.3 years; controls: 23.7 ± 0.9 years), body mass index (dancers: 18.9 ± 0.2; controls: 19.4 ± 0.2 kg/m 2 ), and fat-free mass (dancers: 44.3 ± 0.8; controls: 44.1 ± 0.9 kg). Assessments included habitual dietary intake using 4-day food records, self-reported physical activity, psychometric measures of eating behaviors, health and menstrual history, body composition and bone density (dual energy x-ray absorptiometry), and resting metabolic rate (RMR) assessed by indirect calorimetry. Characteristics of the FT, specifically menstrual irregularities (6 of 15 dancers reported irregular or no menses; 1 of 15 controls reported irregular menses) and low energy availability, were more prevalent in dancers than in pair-matched controls. Despite having a similar fat-free mass (FFM), dancers had a significantly lower absolute RMR (dancers: 1367 ± 27; controls: 1454 ± 34 kcal/d; p ≤ 0.05) and significantly lower RMR relative to FFM (dancers: 30.9 ± 0.6; controls: 33.1 ± 0.8 kcal/kg fat-free mass/d; p ≤ 0.05). Energy intake between dancers (1577 ± 89 kcal/d) and pair-matched controls (2075 ± 163 kcal/d) also differed significantly (p ≤ 0.01). Six of the 15 dancers met the criteria for the FT (including low bone mineral

  16. VHF and UHF radar observations of equatorial F region ionospheric irregularities and background densities

    Science.gov (United States)

    Towle, D. M.

    1980-02-01

    A series of measurements of the properties of equatorial ionospheric irregularities were made at Kwajalein, Marshall Islands (M.I.) in August 1977 and July-August 1978. These measurements, sponsored by the Defense Nuclear Agency (DNA), involved coordinated ground-based and in situ sensors. The ARPA Long-Range Tracking and Instrumentation Radar (ALTAIR), operated by Lincoln Laboratory, obtained backscatter and transmission data during five nights in August 1977 and eight nights in July-August 1978. This report describes the ALTAIR data from the night of August 11, 1978, which yield direct quantitative measurements of 1-m and 3/8-m irregularities and of plasma depleted regions. These plasma depleted regions, previously predicted on the basis of theoretical analysis and in situ data, were observed during the decay phase and not the generative phase of the field-aligned irregularities.

  17. Characteristics and sources of the electron density irregularities in the mid latitude E and Fregions

    Science.gov (United States)

    2017-05-10

    and has since been monitoring the occurrence of field-aligned irregularities ( FAIs ) in the northern middle latitudes. We investigated the...characteristics and occurrence climatology of the FAIs in the middle latitude E- and F-region ionosphere using the Daejeon VHF radar data. Depending on the...sunset and post-sunrise periods. The F-region FAIs in the mid-latitude are bounded to occur during the nighttime between local sunset and sunrise [J

  18. Obtaining source current density related to irregularly structured electromagnetic target field inside human body using hybrid inverse/FDTD method.

    Science.gov (United States)

    Han, Jijun; Yang, Deqiang; Sun, Houjun; Xin, Sherman Xuegang

    2017-01-01

    Inverse method is inherently suitable for calculating the distribution of source current density related with an irregularly structured electromagnetic target field. However, the present form of inverse method cannot calculate complex field-tissue interactions. A novel hybrid inverse/finite-difference time domain (FDTD) method that can calculate the complex field-tissue interactions for the inverse design of source current density related with an irregularly structured electromagnetic target field is proposed. A Huygens' equivalent surface is established as a bridge to combine the inverse and FDTD method. Distribution of the radiofrequency (RF) magnetic field on the Huygens' equivalent surface is obtained using the FDTD method by considering the complex field-tissue interactions within the human body model. The obtained magnetic field distributed on the Huygens' equivalent surface is regarded as the next target. The current density on the designated source surface is derived using the inverse method. The homogeneity of target magnetic field and specific energy absorption rate are calculated to verify the proposed method.

  19. Observation of total electron content and irregularities in electron density using GHz band radiowaves emitted from satellite

    International Nuclear Information System (INIS)

    Ogawa, Tadahiko; Fujita, Masaharu; Awaka, Jun.

    1978-01-01

    The experiments to investigate the influence of troposphere on millimeter and sub-millimeter wave propagation were carried out, using the engineering test satellite -- 2 (ETS-2) which became the Japanese first stationary satellite and carries the transmitter emitting beacon waves of 1.7, 11.5 and 34.5 GHz coherent each other. By these experiments, it was found that the waves of 1.7 and 11.5 GHz were affected by the ionosphere. The measurement of total electron content using GHz band waves was the first trial in the world, and is capable of grasping its change with higher accuracy than conventional methods. Scintillation of 1.7 GHz is mainly the phenomenon during night, and it was revealed that it has a peak at 22.30 local time and occurred through the radiowave scattering owing to the irregularities of the ionosphere. It is also suggested that some plasma instability is generated in the place where electron density gradient in the ionosphere is large, and the irregularities of fine scale are produced, assuming from GHz band scintillations at the time of magnetic storm. The relations among wave number spectrum, scintillation frequency spectrum and S4 index (statistical quantity to give estimate for scintillation amplitude) can be derived by the weak scattering theory (Simple scattering theory). As seen above, the diagnosis of plasma disturbances in the ionosphere is feasible by the simultaneous observations of total electron content and scintillation. (Wakatsuki, Y.)

  20. Online diagnoses of high current-density beams

    International Nuclear Information System (INIS)

    Gilpatrick, J.D.

    1994-01-01

    Los Alamos National Laboratory has proposed several CW-proton-beam facilities for production of tritium or transmutation of nuclear waste with beam-current densities greater than 5 mA/mm 2 . The primary beam-diagnostics-instrumentation requirement for these facilities is provision of sufficient beam information to understand and minimize beam-loss. To accomplish this task, the beam-diagnostics instrumentation must measure beam parameters such as the centroids and profiles, total integrated current, and particle loss. Noninterceptive techniques must be used for diagnosis of high-intensity CW beam at low energies due to the large quantity of power deposited in an interceptive diagnostic device by the beam. Transverse and longitudinal centroid measurements have been developed for bunched beams by measuring and processing image currents on the accelerator walls. Transverse beam-profile measurement-techniques have also been developed using the interaction of the particle beam with the background gases near the beam region. This paper will discuss these noninterceptive diagnostic Techniques

  1. Dependence of cosmological energy-density irregularities on the shape of the scalar-field potential during inflation and ''reheating''

    International Nuclear Information System (INIS)

    Ratra, B.

    1991-01-01

    Estimates for the baryon-dominated epoch form of the large-scale adiabatic energy-density irregularities generated during an early scalar-field-dominated inflation epoch, in simple inflation-modified hot-big-bang models, are compared to the widely used approximate general expression, which is proportional to the large-scale, gauge-invariant part of H 2 left-angle φφ * right-angle/(Φ b ) 2 evaluated at the first Hubble radius crossing (here Φ b and φ are the spatially homogeneous and inhomogeneous parts of the scalar field, H is the Hubble parameter, and an overdot represents a derivative with respect to time). In the de Sitter inflation limit, if the inflation-epoch background scalar-field solution is an ''attractor,'' or if there is sufficient inflation before the scale of interest leaves the Hubble radius, the approximate general expression identically reproduces what we have found. It is also less than an order of magnitude away from our expression in a large fraction of the parameter space of the inflation model we study and is within 2 orders of magnitude of our result in almost all of parameter space. We also show that the more accurate general expression (which the above formula is an approximation of) identically reproduces our results in the simple models studied, provided the inflation-epoch background scalar-field solution is an ''attractor'' or if there is sufficient inflation. The approximate general formula is used to restudy energy-density inhomogeneities in the quartic-potential scalar-field de Sitter inflation model; the difference between the standard result in this model and our result in related models is traced to a difference in the form of the part of the potential used to model ''reheating'' and the end of inflation

  2. Electric Field and Plasma Density Observations of Irregularities and Plasma Instabilities in the Low Latitude Ionosphere Gathered by the C/NOFS Satellite

    Science.gov (United States)

    Pfaff, Robert F.; Freudenreich, H.; Rowland, D.; Klenzing, J.; Liebrecht, C.

    2012-01-01

    The Vector Electric Field Investigation (VEFI) on the C/NOFS equatorial satellite provides a unique data set which includes detailed measurements of irregularities associated with the equatorial ionosphere and in particular with spread-F depletions. We present vector AC electric field observations gathered on C/NOFS that address a variety of key questions regarding how plasma irregularities, from meter to kilometer scales, are created and evolve. The talk focuses on occasions where the ionosphere F-peak has been elevated above the C/NOFS satellite perigee of 400 km as solar activity has increased. In particular, during the equinox periods of 2011, the satellite consistently journeyed below the F-peak whenever the orbit was in the region of the South Atlantic anomaly after sunset. During these passes, data from the electric field and plasma density probes on the satellite have revealed two types of instabilities which had not previously been observed in the C/NOFS data set: The first is evidence for 400-500km-scale bottomside "undulations" that appear in the density and electric field data. In one case, these large scale waves are associated with a strong shear in the zonal E x B flow, as evidenced by variations in the meridional (outward) electric fields observed above and below the F-peak. These undulations are devoid of smaller scale structures in the early evening, yet appear at later local times along the same orbit associated with fully-developed spread-F with smaller scale structures. This suggests that they may be precursor waves for spread-F, driven by a collisional shear instability, following ideas advanced previously by researchers using data from the Jicamarca radar. A second result is the appearance of km-scale irregularities that are a common feature in the electric field and plasma density data that also appear when the satellite is near or below the F-peak at night. The vector electric field instrument on C/NOFS clearly shows that the electric field

  3. Reduced bone mineral density in adult women diagnosed with menstrual disorders during adolescence.

    Science.gov (United States)

    Wiksten-Almströmer, Marianne; Hirschberg, Angelica Lindën; Hagenfeldt, Kerstin

    2009-01-01

    To evaluate the long-term effects on bone mineral density (BMD) in women diagnosed with menstrual disorders in their adolescence. Prospective follow-up study six years after the initial investigation. A youth clinic that is part of the school health system in Stockholm. Eighty-seven women diagnosed with secondary amenorrhea or oligomenorrhea in adolescence. Subjects underwent gynecological examination, evaluation of eating behavior and physical activity. Whole body Dual Energy X-ray Absorptiometry was used for measurement of BMD. BMD. The overall frequency of osteopenia/osteoporosis was 52%, and three girls had osteoporosis. Women with previous secondary amenorrhea had significantly lower BMD in the pelvis and lumbar spine than those with previous oligomenorrhea. The strongest predictor of low BMD was a restrictive eating disorder in adolescence and the most important counteraction was high physical activity at follow-up and a body mass index (BMI) > or = 22. Persistent menstrual dysfunction at follow-up was associated with polycystic ovary syndrome and lower frequency of osteopenia. This clinical follow-up study has demonstrated a high frequency of osteopenia in women diagnosed with menstrual disorders in adolescence. Previous anorectic behavior was the strongest negative predictor of BMD. It is important to pay attention to an underlying eating disorder in young women with menstrual dysfunction in order to promote bone health.

  4. Shack-Hartmann Electron Densitometer (SHED): An Optical System for Diagnosing Free Electron Density in Laser-Produced Plasmas

    Science.gov (United States)

    2016-11-01

    Free Electron Density in Laser-Produced Plasmas by Anthony R Valenzuela Approved for public release; distribution is...AND SUBTITLE Shack-Hartmann Electron Densitometer (SHED): An Optical System for Diagnosing Free Electron Density in Laser-Produced Plasmas 5a...SUPPLEMENTARY NOTES 14. ABSTRACT The Shack-Hartmann Electron Densitometer is a novel method to diagnose ultrashort pulse laser–produced plasmas

  5. Bone mineral density and nutritional indices in adolescent females with recently diagnosed anorexia

    International Nuclear Information System (INIS)

    Wong, J.C.H.; Lewindon, P.J.; Mortimer, R.; Sheperd, R.W.; Royal Children's Hospital, Brisbane, QLD

    1999-01-01

    Full text: Osteopenia/osteoporosis and fractures have been shown to occur with anorexia nervosa (AN). This study evaluated adolescent females diagnosed with AN less than 12 months previously to determine the presence of any significant bone mass reduction at this early stage of diagnosis and to evaluate the correlation between total body (TB) and lumbar spine (LS) bone mineral densities (BMD) and bone mineral content (BMC), and nutritional indices (body weight, body mass index (BMI), lean mass, fat mass and percentage fat). The subjects were 22 adolescent females aged 12-17 years (mean= 14.3 years) diagnosed with AN less than 12 months earlier (range 2.5-11 months; mean = 6.7 months). They had bone density measurements of the TB and LS using a Lunar DPX-L densitometer. Comparison was made with values of age-matched controls in the Lunar normative database. Although there was a tendency towards low TB and LS bone mass, these changes were not statistically significant. Bivariate analyses showed significant correlation between TB BMD and lean mass (P < 0.001) and weight (P < 0.001) and between TB BMC and lean mass (P < 0.001) and weight (P < 0.01). There was similar significant correlation between LS BMD and lean mass (P < 0.01) and weight (P<0.01), and between LS BMC and lean mass (P < 0.01) and weight (P < 0.01). With stepwise regression analysis, only lean mass remained significantly correlated with TB BMD and BMC and LS BMD and BMC. There was no longer any significant correlation with weight. In this study, the weight percentile was found to be correlated highly with the LS BMD Z-score (P < 0.01). Therefore, during adolescence, the lean mass in particular, but also body weight, are good indicators of bone densities. Adolescent females do not appear to show bone mass reduction in the early stages of diagnosis of anorexia nervosa. This suggests early intervention may preserve bone gain and attainment of normal peak bone mass

  6. Radar observations of density gradients, electric fields, and plasma irregularities near polar cap patches in the context of the gradient-drift instability

    Science.gov (United States)

    Lamarche, Leslie J.; Makarevich, Roman A.

    2017-03-01

    We present observations of plasma density gradients, electric fields, and small-scale plasma irregularities near a polar cap patch made by the Super Dual Auroral Radar Network radar at Rankin Inlet (RKN) and the northern face of Resolute Bay Incoherent Scatter Radar (RISR-N). RKN echo power and occurrence are analyzed in the context of gradient-drift instability (GDI) theory, with a particular focus on the previously uninvestigated 2-D dependencies on wave propagation, electric field, and gradient vectors, with the latter two quantities evaluated directly from RISR-N measurements. It is shown that higher gradient and electric field components along the wave vector generally lead to the higher observed echo occurrence, which is consistent with the expected higher GDI growth rate, but the relationship with echo power is far less straightforward. The RKN echo power increases monotonically as the predicted linear growth rate approaches zero from negative values but does not continue this trend into positive growth rate values, in contrast with GDI predictions. The observed greater consistency of echo occurrence with GDI predictions suggests that GDI operating in the linear regime can control basic plasma structuring, but measured echo strength may be affected by other processes and factors, such as multistep or nonlinear processes or a shear-driven instability.

  7. Usefulness of transrectal ultrasound in diagnosing prostate cancer: comparison with digital rectal examination, prostate-specific antigen and prostate-specific antigen density

    International Nuclear Information System (INIS)

    Yoon, Jung Hwan; Kim, Bo Hyun; Choi, Sang Hee; Kim, Seung Hoon; Choi, Han Yong; Chai, Soo Eung; Yoon, Hye Kyung; Lee, Soon Jin; Choo, In Wook; Kim, Bo Kyung

    1998-01-01

    To determine the usefulness of transrectal ultrasonography (TRUS) in diagnosing prostate cancer by comparing the sensitivity, specificity, accuracy, and positive and negative predictive values of TRUS with those of serum prostate-specific antigen (PSA), prostate-specific antigen density (PSAD) and digital rectal examination (DRE). Two hundred and ten consecutive patients underwent TRUS-guided prostate biopsy due to elevated PSA and/or abnormal findings on TRUS or DRE. The TRUS findings were analyzed and correlated with pathological diagnosis. PSAD was calculated by dividing the serum PSA level by the prostate volume calculated on TRUS. The sensitivity, specificity, accuracy, and positive and negative predictive values of TRUS were compared with those of PSA, PSAD and DRE. Using ROC curve analysis, the combinations of these diagnostic methods were also evaluated for the determination of efficacy in diagnosing prostate cancer. The sensitivity and specificity of serum PSA (cut-off level, 4ng/ml), PSAD (cut-off level, 0.15ng/ml/cm 3 ), DRE, and TRUS were 96%/17%, 96%/37%, 72%/62%, and 89%/68%, respectively. On TRUS, the sensitivity and specificity of low echoic lesions and those of irregular outer margin were 89%/69%, and 60%/90%, respectively. TRUS was statistically more accurate than other diagnostic methods. Of the combinations of diagnostic methods, TRUS and PSAD were most accurate. TRUS demonstrated lower sensitivity but higher specificity than PSA or PSAD. Although it is an accurate modality for the diagnosis of prostate cancer, it cannot be used as a confirmative test due to its relatively low positive predictive value. A combination of diagnostic methods and random biopsy is needed in patients in whom prostate cancer is suspected.=20

  8. Irregular Applications: Architectures & Algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Feo, John T.; Villa, Oreste; Tumeo, Antonino; Secchi, Simone

    2012-02-06

    Irregular applications are characterized by irregular data structures, control and communication patterns. Novel irregular high performance applications which deal with large data sets and require have recently appeared. Unfortunately, current high performance systems and software infrastructures executes irregular algorithms poorly. Only coordinated efforts by end user, area specialists and computer scientists that consider both the architecture and the software stack may be able to provide solutions to the challenges of modern irregular applications.

  9. Low bone mineral density among patients with newly diagnosed rheumatoid arthritis

    International Nuclear Information System (INIS)

    Arain, S.R.; Riaz, A.; Nazir, L.; Umer, T.P.; Rasool, T.

    2016-01-01

    Background: Osteoporosis is an early and common feature in rheumatoid arthritis. Apart from other manifestations, Osteoporosis is an extra-articular manifestation of rheumatoid arthritis which may result in increased risk of fractures, morbidity, mortality, and associated healthcare costs. This study evaluates bone mineral density changes in patients with rheumatoid arthritis of recent-onset. Methods: This descriptive case series was conducted in the Rheumatology Department of a tertiary care hospital in Karachi. Data was prospectively collected from 76 patients presenting with seropositive or seronegative rheumatoid arthritis. Bone mineral density of these patients measured at lumbar spine and hip by using dual energy x-ray absorptiometry scan. Variables like age, gender, BMI, menstrual status, disease duration, erythrocyte sedimentation rate, vitamin D level, clinical disease activity index and seropositivity for rheumatoid arthritis were measured along with outcome variables. Results: A total of 104 patients fulfilling inclusion criteria were registered with 28 excluded from study. Among the remaining 76 patients, 68 (89.50 percentage) were female, with mean age of patients (with low bone mineral density) as 50.95±7.87 years. Nineteen (25 percentage) patients had low bone mineral density, 68.52 percentage had low BMD at spine while 10.52 percentage at hip and 21.05 percentage at spine and hip both. Low bone mineral density was found higher in patients with seronegative 7 (50 percentage) as compared to seropositive patients 12 (19.4 percentage) (p-value 0.017), whereas low bone mineral density was found higher 12 (70.6 percentage) among post-menopausal women. Conclusion: Low BMD was found in 25 percentage of patients at earlier stage of the rheumatoid arthritis with seropositivity, age and menopausal status as significant risk factors. (author)

  10. Diagnosing high density, fast-evolving plasmas using x-ray lasers

    International Nuclear Information System (INIS)

    Cauble, R.; Da Silva, L.B.; Barbee, T.W. Jr.

    1994-09-01

    As x-ray laser (XRL) research has matured, it has become possible to reliably utilize XRLs for applications in the laboratory. Laser coherence, high brightness and short pulse duration all make the XRL a unique tool for the diagnosis of laboratory plasmas. The high brightness of XRLs makes them well-suited for imaging and for interferometry when used in conjunction with multilayer mirrors and beamsplitters. We have utilized a soft x-ray laser in such an imaging system to examine laser-produced plasmas using radiography, moire deflectometry, and interferometry. Radiography experiments yield 100-200 ps snapshots of laser driven foils at a resolution of 1-2 μm. Moire deflectometry with an XRL has been used to probe plasmas at higher density than by optical means. Interferograms, which allow direct measurement of electron density in laser plasmas, have been obtained with this system

  11. ANÁLISIS Y ESTUDIO DEL DESEMPEÑO DEL CÓDIGO CHEQUEO DE PARIDAD DE BAJA DENSIDAD IRREGULAR EN UN CANAL DE LÍNEA ELÉCTRICA DE BAJA TENSIÓN ANALYSIS AND STUDY OF THE PERFORMANCE OF THE IRREGULAR LOW DENSITY PARITY CHECK CODE IN LOW VOLTAGE POWERLINE

    Directory of Open Access Journals (Sweden)

    Washington Fernández R

    2009-04-01

    Full Text Available En este trabajo se analiza y estudia el código chequeo de paridad de baja densidad irregular (LDPC, en un canal de línea eléctrica de baja tensión. Se analizan los modelos de ruido existentes para las líneas eléctricas de baja tensión. Se evalúa el desempeño del código LDPC irregular, en un canal de línea eléctrica de baja tensión para diferentes velocidades de transmisión (3, 10, 15 y 30 Mbps, considerando como parámetro de desempeño el BER versus SNR.In this work the irregular Low Density Parity Check code (LDPC is analyzed and studied, is used in a low voltage powerline. Noise models are analyzed for these low voltage lines. The performance of the LDPC code is evaluated in a low voltage line channel for rates of 3, 5, 15 and 30 Mbps, considering of BER vs SNR a parameter.

  12. The relationship between small-scale and large-scale ionospheric electron density irregularities generated by powerful HF electromagnetic waves at high latitudes

    Directory of Open Access Journals (Sweden)

    E. D. Tereshchenko

    2006-11-01

    Full Text Available Satellite radio beacons were used in June 2001 to probe the ionosphere modified by a radio beam produced by the EISCAT high-power, high-frequency (HF transmitter located near Tromsø (Norway. Amplitude scintillations and variations of the phase of 150- and 400-MHz signals from Russian navigational satellites passing over the modified region were observed at three receiver sites. In several papers it has been stressed that in the polar ionosphere the thermal self-focusing on striations during ionospheric modification is the main mechanism resulting in the formation of large-scale (hundreds of meters to kilometers nonlinear structures aligned along the geomagnetic field (magnetic zenith effect. It has also been claimed that the maximum effects caused by small-scale (tens of meters irregularities detected in satellite signals are also observed in the direction parallel to the magnetic field. Contrary to those studies, the present paper shows that the maximum in amplitude scintillations does not correspond strictly to the magnetic zenith direction because high latitude drifts typically cause a considerable anisotropy of small-scale irregularities in a plane perpendicular to the geomagnetic field resulting in a deviation of the amplitude-scintillation peak relative to the minimum angle between the line-of-sight to the satellite and direction of the geomagnetic field lines. The variance of the logarithmic relative amplitude fluctuations is considered here, which is a useful quantity in such studies. The experimental values of the variance are compared with model calculations and good agreement has been found. It is also shown from the experimental data that in most of the satellite passes a variance maximum occurs at a minimum in the phase fluctuations indicating that the artificial excitation of large-scale irregularities is minimum when the excitation of small-scale irregularities is maximum.

  13. Hyponatremia and decreased bone density in adolescent inpatients diagnosed with anorexia nervosa.

    Science.gov (United States)

    Levy-Shraga, Yael; David, Dana; Vered, Iris; Kochavi, Brigitte; Stein, Daniel; Modan-Moses, Dalit

    2016-10-01

    Recent studies demonstrated an association between low serum sodium levels and reduced bone density. Patients with anorexia nervosa (AN) are at greater risk for osteoporosis as well as for hyponatremia. The aim of the present study was to assess the association between hyponatremia and bone mineral density (BMD) in a large cohort of adolescent inpatients with AN. A historic cohort study of 174 adolescent females (mean age 15.7 ± 1.8 y) hospitalized because of AN between 2003 and 2013. Demographic and clinical data, including age, psychiatric comorbidity, anthropometric measurements, laboratory tests, and BMD scores were obtained from the patients' medical charts. Mean lumbar spine BMD z-score of the patients was lower than expected in the normal population (mean -1.5 ± 1.2) and positively correlated with body mass index standard deviation score (r = 0.42, P adolescent females with AN. Additional studies are required to evaluate whether the correction of hyponatremia will improve BMD. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Star Formation in Irregular Galaxies.

    Science.gov (United States)

    Hunter, Deidre; Wolff, Sidney

    1985-01-01

    Examines mechanisms of how stars are formed in irregular galaxies. Formation in giant irregular galaxies, formation in dwarf irregular galaxies, and comparisons with larger star-forming regions found in spiral galaxies are considered separately. (JN)

  15. New Model for Ionospheric Irregularities at Mars

    Science.gov (United States)

    Keskinen, M. J.

    2018-03-01

    A new model for ionospheric irregularities at Mars is presented. It is shown that wind-driven currents in the dynamo region of the Martian ionosphere can be unstable to the electromagnetic gradient drift instability. This plasma instability can generate ionospheric density and magnetic field irregularities with scale sizes of approximately 15-20 km down to a few kilometers. We show that the instability-driven magnetic field fluctuation amplitudes relative to background are correlated with the ionospheric density fluctuation amplitudes relative to background. Our results can explain recent observations made by the Mars Atmosphere and Volatile EvolutioN spacecraft in the Martian ionosphere dynamo region.

  16. Understanding the Unique Equatorial Density Irregularities

    Science.gov (United States)

    2015-04-01

    research, 55, 184-198, 2015. • Tesema, F., B. Damtie, M. Nigussie, The response of the ionosphere to intense geomagnetic storms in 2012 using GPS-TEC...Approved for public release; distribution is unlimited. fountain effect between 1000 to 1500 UT, which could be due to strong pre- reversal enhancement of...investigate different ionospheric phenomena such as the effect of the geomagnetic disturbance on the distribution of the low latitude ionospheric electron

  17. Saturn's Irregular Moon Ymir

    Science.gov (United States)

    Denk, Tilmann; Mottola, S.

    2012-10-01

    Ymir (diameter 18 km), Saturn's second largest retrograde outer or irregular moon, has been observed six times by the Cassini narrow-angle camera (NAC) during the first 7 months in 2012. The observations span phase angles from 2° up to 102° and were taken at ranges between 15 and 18 million kilometers. From such a distance, Ymir is smaller than a pixel in the Cassini NAC. The data reveal a sidereal rotation period of 11.93 hrs, which is 1.6x longer than the previously reported value (Denk et al. 2011, EPSC/DPS #1452). Reason for this discrepancy is that the rotational light curve shows a rather uncommon 3-maxima and 3-minima shape at least in the phase angle range 50° to 100°, which was not recognizable in earlier data. The data cover several rotations from different viewing and illumination geometries and allow for a convex shape inversion with possibly a unique solution for the pole direction. The model reproduces the observed light curves to a very good accuracy without requiring albedo variegation, thereby suggesting that the lightcurve is dominated by the shape of Ymir. Among Saturn's irregular moons, the phenomenon of more than two maxima and minima at moderate to high phase angles is not unique to Ymir. At least Siarnaq and Paaliaq also show light curves with a strong deviation from a double-sine curve. Their rotation periods, however, remain unknown until more data can be taken. The light curve of Phoebe is fundamentally different to Ymir's because it is mainly shaped by local albedo differences and not by shape. Other reliable rotation periods of irregular satellites measured by Cassini include: Mundilfari 6.74 h; Kari 7.70 h; Albiorix 13.32 h; Kiviuq 21.82 h. More uncertain values are: Skathi 12 h; Bebhionn 16 h; Thrymr 27 h; Erriapus 28 h.

  18. The density of parasympathetic axons is reduced in the exocrine pancreas of individuals recently diagnosed with type 1 diabetes.

    Science.gov (United States)

    Lundberg, Marcus; Lindqvist, Andreas; Wierup, Nils; Krogvold, Lars; Dahl-Jørgensen, Knut; Skog, Oskar

    2017-01-01

    To elucidate the etiology of type 1 diabetes, the affected pancreas needs to be thoroughly characterized. Pancreatic innervation has been suggested to be involved in the pathology of the disease and a reduction of sympathetic innervation of the islets was recently reported. In the present study, we hypothesized that parasympathetic innervation would be altered in the type 1 diabetes pancreas. Human pancreatic specimens were obtained from a unique cohort of individuals with recent onset or long standing type 1 diabetes. Density of parasympathetic axons was assessed by immunofluorescence and morphometry. Our main finding was a reduced density of parasympathetic axons in the exocrine, but not endocrine compartment of the pancreas in individuals with recent onset type 1 diabetes. The reduced density of parasympathetic axons in the exocrine compartment could have functional implications, e.g. be related to the exocrine insufficiency reported in type 1 diabetes patients. Further studies are needed to understand whether reduced parasympathetic innervation is a cause or consequence of type 1 diabetes.

  19. The density of parasympathetic axons is reduced in the exocrine pancreas of individuals recently diagnosed with type 1 diabetes.

    Directory of Open Access Journals (Sweden)

    Marcus Lundberg

    Full Text Available To elucidate the etiology of type 1 diabetes, the affected pancreas needs to be thoroughly characterized. Pancreatic innervation has been suggested to be involved in the pathology of the disease and a reduction of sympathetic innervation of the islets was recently reported. In the present study, we hypothesized that parasympathetic innervation would be altered in the type 1 diabetes pancreas. Human pancreatic specimens were obtained from a unique cohort of individuals with recent onset or long standing type 1 diabetes. Density of parasympathetic axons was assessed by immunofluorescence and morphometry. Our main finding was a reduced density of parasympathetic axons in the exocrine, but not endocrine compartment of the pancreas in individuals with recent onset type 1 diabetes. The reduced density of parasympathetic axons in the exocrine compartment could have functional implications, e.g. be related to the exocrine insufficiency reported in type 1 diabetes patients. Further studies are needed to understand whether reduced parasympathetic innervation is a cause or consequence of type 1 diabetes.

  20. Triglyceride to high-density lipoprotein cholesterol ratio and carotid intima-medial thickness in Chinese adolescents with newly diagnosed type 2 diabetes mellitus.

    Science.gov (United States)

    Li, Xin; Deng, You-Ping; Yang, Miao; Wu, Yu-Wen; Sun, Su-Xin; Sun, Jia-Zhong

    2016-03-01

    To investigate the relationship between triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio and carotid intima-medial thickness (CIMT) in Chinese youth and adolescents with newly diagnosed type 2 diabetes mellitus (T2DM). Ninety-eight subjects aged 10-24 yr with newly-diagnosed T2DM had general inflammation, anthropometric, laboratory and CIMT data collected, and were divided into three groups based on TG/HDL-C tertiles. There were no significant differences in gender, age, fasting plasma glucose (FPG), hemoglobin A1c (HbA1c), and carotid arterial diameter (CAD) among the groups based on TG/HDL-C tertiles. Across TG/HDL-C tertiles, there was a significant progressive increase in body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), homeostasis model assessment-estimated insulin resistance (HOMA-IR), TG, total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C) and CIMT (all P < 0.01 or P < 0.05), while HDL-C was decreased significantly across the groups (P < 0.01). In general linear regression model, TG/HDL-C was an independent determinant of CIMT even after adjusting for BMI, SBP, DBP, TG, TC, LDL-C, HDL-C, HbA1c and HOMA-IR. TG/HDL-C ratio, the marker of small dense LDL particles, is an independent determinant of CIMT in Chinese youth and adolescents with newly diagnosed T2DM, and may be a simple and helpful tool in predicting the increased CIMT in such patients. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Irregular Migrants and the Law

    OpenAIRE

    Kassim, Azizah; Mat Zin, Ragayah Hj.

    2013-01-01

    This paper examines Malaysia`s policy on irregular migrants and its implementation, and discusses its impact. A survey and interview covering 404 respondents was conducted between July 2010 and June 2011 to ascertain the real situations surrounding irregular migrants in Malaysia, which is one of the major host countries of international migrants from developing nations. The policy on foreign workers was formulated in the mid-1980s to deal with the large number of irregular migrants and their ...

  2. How Do Health Care Providers Diagnose Menstrual Irregularities?

    Science.gov (United States)

    ... NICHD Research Information Find a Study More Information Amenorrhea About NICHD Research Information Find a Study More ... 291. Master-Hunter, T., & Heiman, D. L. (2006). Amenorrhea: Evaluation and treatment. American Family Physician , 73, 1374– ...

  3. Strategic Analysis of Irregular Warfare

    Science.gov (United States)

    2010-03-01

    the same mathematical equations used by Lanchester .10 Irregular Warfare Theory and Doctrine It is time to develop new analytical methods and models...basis on which to build, similar to what Lanchester provided almost 100 years ago. Figure 9 portrays both Lanchester’s approach and an irregular 17

  4. Circulating and intraprostatic sex steroid hormonal profiles in relation to male pattern baldness and chest hair density among men diagnosed with localized prostate cancers.

    Science.gov (United States)

    Zhou, Cindy Ke; Stanczyk, Frank Z; Hafi, Muhannad; Veneroso, Carmela C; Lynch, Barlow; Falk, Roni T; Niwa, Shelley; Emanuel, Eric; Gao, Yu-Tang; Hemstreet, George P; Zolfghari, Ladan; Carroll, Peter R; Manyak, Michael J; Sesterhenn, Isabell A; Levine, Paul H; Hsing, Ann W; Cook, Michael B

    2017-12-01

    Prospective cohort studies of circulating sex steroid hormones and prostate cancer risk have not provided a consistent association, despite evidence from animal and clinical studies. However, studies using male pattern baldness as a proxy of early-life or cumulative androgen exposure have reported significant associations with aggressive and fatal prostate cancer risk. Given that androgens underlie the development of patterned hair loss and chest hair, we assessed whether these two dermatological characteristics were associated with circulating and intraprostatic concentrations of sex steroid hormones among men diagnosed with localized prostate cancer. We included 248 prostate cancer patients from the NCI Prostate Tissue Study, who answered surveys and provided a pre-treatment blood sample as well as fresh frozen adjacent normal prostate tissue. Male pattern baldness and chest hair density were assessed by trained nurses before surgery. General linear models estimated geometric means and 95% confidence intervals (95%CIs) of each hormone variable by dermatological phenotype with adjustment for potential confounding variables. Subgroup analyses were performed by Gleason score (balding status with serum testosterone, dihydrotestosterone (DHT), estradiol, and sex hormone-binding globulin (SHBG), and a weak association with elevated intraprostatic testosterone. Conversely, neither circulating nor intraprostatic sex hormones were statistically significantly associated with chest hair density. Age-adjusted correlation between binary balding status and three-level chest hair density was weak (r = 0.05). There was little evidence to suggest that Gleason score or race modified these associations. This study provides evidence that balding status assessed at a mean age of 60 years may serve as a clinical marker for circulating sex hormone concentrations. The weak-to-null associations between balding status and intraprostatic sex hormones reaffirm differences in organ

  5. Irregular Dwarf Galaxy IC 1613

    Science.gov (United States)

    2005-01-01

    Ultraviolet image (left) and visual image (right) of the irregular dwarf galaxy IC 1613. Low surface brightness galaxies, such as IC 1613, are more easily detected in the ultraviolet because of the low background levels compared to visual wavelengths.

  6. Design Optimization of Irregular Cellular Structure for Additive Manufacturing

    Science.gov (United States)

    Song, Guo-Hua; Jing, Shi-Kai; Zhao, Fang-Lei; Wang, Ye-Dong; Xing, Hao; Zhou, Jing-Tao

    2017-09-01

    Irregularcellular structurehas great potential to be considered in light-weight design field. However, the research on optimizing irregular cellular structures has not yet been reporteddue to the difficulties in their modeling technology. Based on the variable density topology optimization theory, an efficient method for optimizing the topology of irregular cellular structures fabricated through additive manufacturing processes is proposed. The proposed method utilizes tangent circles to automatically generate the main outline of irregular cellular structure. The topological layoutof each cellstructure is optimized using the relative density informationobtained from the proposed modified SIMP method. A mapping relationship between cell structure and relative densityelement is builtto determine the diameter of each cell structure. The results show that the irregular cellular structure can be optimized with the proposed method. The results of simulation and experimental test are similar for irregular cellular structure, which indicate that the maximum deformation value obtained using the modified Solid Isotropic Microstructures with Penalization (SIMP) approach is lower 5.4×10-5 mm than that using the SIMP approach under the same under the same external load. The proposed research provides the instruction to design the other irregular cellular structure.

  7. GARCH and Irregularly Spaced Data

    NARCIS (Netherlands)

    Meddahi, N.; Renault, E.; Werker, B.J.M.

    2003-01-01

    An exact discretization of continuous time stochastic volatility processes observed at irregularly spaced times is used to give insights on how a coherent GARCH model can be specified for such data. The relation of our approach with those in the existing literature is studied.

  8. Characteristics of low latitude ionospheric E-region irregularities ...

    Indian Academy of Sciences (India)

    154°E, dip angle = 37.3°, sub-ionospheric dip = 34°) have been analyzed to study the behaviour of ionospheric E-region irregularities during the active solar and magnetic periods. The autocorrelation functions, power spectral densities, signal de-correlation times are computed to study the temporal features of ionospheric ...

  9. Propagation and scattering of electromagnetic waves by the ionospheric irregularities

    International Nuclear Information System (INIS)

    Ho, A.Y.; Kuo, S.P.; Lee, M.C.

    1993-01-01

    The problem of wave propagation and scattering in the ionosphere is particularly important in the areas of communications, remote-sensing and detection. The ionosphere is often perturbed with coherently structured (quasiperiodic) density irregularities. Experimental observations suggest that these irregularities could give rise to significant ionospheric effect on wave propagation such as causing spread-F of the probing HF sounding signals and scintillation of beacon satellite signals. It was show by the latter that scintillation index S 4 ∼ 0.5 and may be as high as 0.8. In this work a quasi-particle theory is developed to study the scintillation phenomenon. A Wigner distribution function for the wave intensity in the (k,r) space is introduced and its governing equation is derived with an effective collision term giving rise to the attenuation and scattering of the wave. This kinetic equation leads to a hierarchy of moment equations in r space. This systems of equations is then truncated to the second moment which is equivalent to assuming a cold quasi-particle distribution In this analysis, the irregularities are modeled as a two dimensional density modulation on an uniform background plasma. The analysis shows that this two dimensional density grating, effectively modulates the intensity of the beacon satellite signals. This spatial modulation of the wave intensity is converted into time modulation due to the drift of the ionospheric irregularities, which then contributes to the scintillation of the beacon satellite signals. Using the proper plasma parameters and equatorial measured data of irregularities, it is shown that the scintillation index defined by S4=( 2 >- 2 )/ 2 where stands for spatial average over an irregularity wavelength is in the range of the experimentally detected values

  10. Artificial periodic irregularities in the auroral ionosphere

    Directory of Open Access Journals (Sweden)

    M. T. Rietveld

    1996-12-01

    Full Text Available Artificial periodic irregularities (API are produced in the ionospheric plasma by a powerful standing electromagnetic wave reflected off the F region. The resulting electron-density irregularities can scatter other high-frequency waves if the Bragg scattering condition is met. Such measurements have been performed at mid-latitudes for two decades and have been developed into a useful ionospheric diagnostic technique. We report here the first measurements from a high-latitude station, using the EISCAT heating facility near Tromsø, Norway. Both F-region and lower-altitude ionospheric echoes have been obtained, but the bulk of the data has been in the E and D regions with echoes extending down to 52-km altitude. Examples of API are shown, mainly from the D region, together with simultaneous VHF incoherent-scatter-radar (ISR data. Vertical velocities derived from the rate of phase change during the irregularity decay are shown and compared with velocities derived from the ISR. Some of the API-derived velocities in the 75–115-km height range appear consistent with vertical neutral winds as shown by their magnitudes and by evidence of gravity waves, while other data in the 50–70-km range show an unrealistically large bias. For a comparison with ISR data it has proved difficult to get good quality data sets overlapping in height and time. The initial comparisons show some agreement, but discrepancies of several metres per second do not yet allow us to conclude that the two techniques are measuring the same quantity. The irregularity decay time-constants between about 53 and 70 km are compared with the results of an advanced ion-chemistry model, and height profiles of recorded signal power are compared with model estimates in the same altitude range. The calculated amplitude shows good agreement with the data in that the maximum occurs at about the same height as that of the measured amplitude. The calculated time-constant agrees very well with the

  11. Spatial irregularities in Jupiter's upper ionosphere observed by Voyager radio occultations

    Science.gov (United States)

    Hinson, D. P.; Tyler, G. L.

    1982-01-01

    Radio scintillations (at 3.6 and 13 cm) produced by scattering from ionospheric irregularities during the Voyager occultations are interpreted using a weak-scattering theory. Least squares solutions for ionospheric parameters derived from the observed fluctuation spectra yield estimates of (1) the axial ratio, (2) angular orientation of the anisotropic irregularities, (3) the power law exponent of the spatial spectrum of irregularities, and (4) the magnitude of the spatial variations in electron density. It is shown that the measured angular orientation of the anisotropic irregularities indicates magnetic field direction and may provide a basis for refining Jovian magnetic field models.

  12. Bottomside sinusoidal irregularities in the equatorial F region

    Science.gov (United States)

    Valladares, C. E.; Hanson, W. B.; Mcclure, J. P.; Cragin, B. L.

    1983-01-01

    By using the Ogo 6 satellite, McClure and Hanson (1973) have discovered sinusoidal irregularities in the equatorial F region ion number density. In the present investigation, a description is provided of the properties of a distinct category of sinusoidal irregularities found in equatorial data from the AE-C and AE-E satellites. The observed scale sizes vary from about 300 m to 3 km in the direction perpendicular to B, overlapping with and extending the range observed by using Ogo 6. Attention is given to low and high resolution data, a comparison with Huancayo ionograms, the confinement of 'bottomside sinusoidal' (BSS) irregularities essentially to the bottomside of the F layer, spectral characteristics, and BSS, scintillation, and ionosonde observations.

  13. Diagnosing Flu

    Science.gov (United States)

    ... Types Seasonal Avian Swine Variant Pandemic Other Diagnosing Flu Questions & Answers Language: English (US) Español Recommend on ... How do I know if I have the flu? Your respiratory illness might be the flu if ...

  14. Plasma Irregularity Production in the Polar Cap F-Region Ionosphere

    Science.gov (United States)

    Lamarche, Leslie

    Plasma in the Earth's ionosphere is highly irregular on scales ranging between a few centimeters and hundreds of kilometers. Small-scale irregularities or plasma waves can scatter radio waves resulting in a loss of signal for navigation and communication networks. The polar region is particularly susceptible to strong disturbances due to its direct connection with the Sun's magnetic field and energetic particles. In this thesis, factors that contribute to the production of decameter-scale plasma irregularities in the polar F region ionosphere are investigated. Both global and local control of irregularity production are studied, i.e. we consider global solar control through solar illumination and solar wind as well as much more local control by plasma density gradients and convection electric field. In the first experimental study, solar control of irregularity production is investigated using the Super Dual Auroral Radar Network (SuperDARN) radar at McMurdo, Antarctica. The occurrence trends for irregularities are analyzed statistically and a model is developed that describes the location of radar echoes within the radar's field-of-view. The trends are explained through variations in background plasma density with solar illumination affecting radar beam propagation. However, it is found that the irregularity occurrence during the night is higher than expected from ray tracing simulations based on a standard ionospheric density model. The high occurrence at night implies an additional source of plasma density and it is proposed that large-scale density enhancements called polar patches may be the source of this density. Additionally, occurrence maximizes around the terminator due to different competing irregularity production processes that favor a more or less sunlit ionosphere. The second study is concerned with modeling irregularity characteristics near a large-scale density gradient reversal, such as those expected near polar patches, with a particular focus on

  15. C/NOFS Satellite Electric Field and Plasma Density Observations of Plasma Instabilities Below the Equatorial F-Peak -- Evidence for Approximately 500 km-Scale Spread-F "Precursor" Waves Driven by Zonal Shear Flow and km-Scale, Narrow-Banded Irregularities

    Science.gov (United States)

    Pfaff, R.; Freudenreich, H.; Klenzing, J.; Liebrecht, C.; Valladares, C.

    2011-01-01

    As solar activity has increased, the ionosphere F-peak has been elevated on numerous occasions above the C/NOFS satellite perigee of 400km. In particular, during the month of April, 2011, the satellite consistently journeyed below the F-peak whenever the orbit was in the region of the South Atlantic anomaly after sunset. During these passes, data from the electric field and plasma density probes on the satellite have revealed two types of instabilities which had not previously been observed in the C/NOFS data set (to our knowledge): The first is evidence for 400-500km-scale bottomside "undulations" that appear in the density and electric field data. In one case, these large scale waves are associated with a strong shear in the zonal E x B flow, as evidenced by variations in the meridional (outward) electric fields observed above and below the F-peak. These undulations are devoid of smaller scale structures in the early evening, yet appear at later local times along the same orbit associated with fully-developed spread-F with smaller scale structures. This suggests that they may be precursor waves for spread-F, driven by a collisional shear instability, following ideas advanced previously by researchers using data from the Jicamarca radar. A second new result (for C/NOFS) is the appearance of km-scale irregularities that are a common feature in the electric field and plasma density data that also appear when the satellite is below the F -peak at night. The vector electric field instrument on C/NOFS clearly shows that the electric field component of these waves is strongest in the zonal direction. These waves are strongly correlated with simultaneous observations of plasma density oscillations and appear both with, and without, evidence of larger-scale spread-F depletions. These km-scale, quasi-coherent waves strongly resemble the bottomside, sinusoidal irregularities reported in the Atmosphere Explorer satellite data set by Valladares et al. [JGR, 88, 8025, 1983

  16. Evaluation of irregular menses in perimenarcheal girls: a pilot study.

    Science.gov (United States)

    Browner-Elhanan, Karen J; Epstein, Jonathan; Alderman, Elizabeth M

    2003-12-01

    Acyclic vaginal bleeding in girls within three years of menarche is most commonly attributed to an immature hypothalamic-pituitary-ovarian axis. Assuming this diagnosis may preclude the practitioner from performing more definitive studies and thereby diagnosing other, treatable causes of menstrual irregularities. A retrospective chart review of 178 girls presenting to an inner-city hospital-based adolescent clinic within three years of menarche was performed. Personal and family medical and menarcheal history was assessed, and findings on physical and laboratory examination performed were evaluated. Of the 178 girls still perimenarcheal at presentation, 47 were the focus of this study. Of these, 39 had no significant findings on physical examination, while 3 had signs of functional ovarian hyperandrogenism (FOH) including obesity, hirsutism, and moderate acne with corresponding LH/FSH ratios>3, although pelvic ultrasound examination revealed normal ovaries. Four of the 39 patients with normal physical exams had LH/FSH testing done, and 1 of the 4 had an abnormal LH/FSH ratio, indicating possible FOH. Two of the 47 patients were pregnant. Other laboratory abnormalities included microcytic, hypochromic anemia in patients, and an elevated Erythrocyte Sedimentation Rate in a patient later diagnosed with a rheumatologic disorder. Those perimenarcheal girls presenting with irregular menses and findings including obesity, acne, or pallor, were likely to have treatable causes of menstrual irregularities. In one of the four girls with a normal physical examination, hormonal testing indicated possible FOH, thus suggesting that hormonal evaluation of perimenarcheal girls with menstrual irregularities may be justified, as it may reveal previously unsuspected pathology.

  17. Irregular Migration in Jordan, 1995-2007

    OpenAIRE

    AROURI, Fathi A.

    2008-01-01

    Euro-Mediterranean Consortium for Applied Research on International Migration (CARIM) This paper tackles the question of irregular migration in Jordan through its four main aspects. The first concerns irregular labour migrants and has been approached by using figures showing the socio-economic profile of non Jordanians working in Jordan and, additionally, unemployment in Jordan. This is done by assuming close similarities between legal and irregular labour migrants. The second is an attemp...

  18. Multiscale Modeling of Ionospheric Irregularities

    Science.gov (United States)

    2014-10-22

    numerical simulations of ionospheric plasma density structures associated with nonlinear evolution of the Rayleigh-Taylor (RT) instabilities in...model was developed to resolve the transport pat- terns of plasma density coupled with neutral atmospheric dynamics. Inclusion of neutral dynamics in...trapping electromagnetic (EM) waves in parabolic cavities, which are created by the refractive index gradients along the propagation paths. Keywords

  19. Significance of scatter radar studies of E and F region irregularities at high latitudes

    International Nuclear Information System (INIS)

    Greenwald, R.A.

    1983-01-01

    This chapter considers the mechanisms by which electron density irregularities may be generated in the high latitude ionosphere and the techniques through which they are observed with ground base radars. The capabilities of radars used for studying these irregularities are compared with the capabilities of radars used for incoherent scatter measurements. The use of irregularity scatter techniques for dynamic studies of larger scale structured phenomena is discussed. Topics considered include E-region irregularities, observations with auroral radars, plasma drifts associated with a westward travelling surge, and ionospheric plasma motions associated with resonant waves. It is shown why high latitude F-region irregularity studies must be made in the HF frequency band (3-30 MHz). The joint use of the European Incoherent Scatter Association (EISCAT), STARE and SAFARI facilities is examined, and it is concluded that the various techniques will enhance each other and provide a better understanding of the various processes being studied

  20. Ethical issues in irregular migration research

    NARCIS (Netherlands)

    Duvell, F.; Triandafyllidou, A.; Vollmer, B.

    2008-01-01

    This paper is concerned with the ethical issues arising for researchers engaged in the study of irregular migration. Irregular migration is by definition an elusive phenomenon as it takes place in violation of the law and at the margins of society. This very nature of the phenomenon raises important

  1. PROBLEM ON IRREGULAR 3-DIMENSIONAL DENSITY DISCONTINUITY SURFACES.

    Science.gov (United States)

    method. The result is used to analyze the relation of linear correlation between the crustal thickness and the local Bouguer gravity anomaly, and good agreement is obtained in comparison with the actual statistical data. (Author)

  2. Spatial irregularities in Jupiter's upper ionosphere observed by voyager radio occultations

    Energy Technology Data Exchange (ETDEWEB)

    Hinson, D.P.; Tyler, G.L.

    1982-07-01

    Dual frequency radio occultation experiments carried out with Voyagers 1 and 2 provided data on the spatial irregularities in Jupiter's ionosphere at four different locations. Sample spectra of weak fluctuations in amplitude and phase of the 3.6-cm and 13-cm wavelength radio signals can be interpreted by using the theory for scattering from an anisotropic power law phase screen. Least squares solutions for ionospheric parameters derived from the observed fluctuation spectra yielded estimates of (1) the axial ratio, (2) angular orientation of the anisotropic irregularities, (3) the power law exponent of the spatial spectrum of irregularities, and (4) the magnitude of the spatial variations in electron density. Equipment limitations and the method of analysis constrain the observations to irregularities of approximate size 1--200 km. No evidence of the inner or outer scale of the irregularities was found. For length scales in the range given, the three-dimensional spatial spectrum obeys a power law with exponent varying from -3.0 to -3.7, and the root mean square fractional variations in electron density are 1--15%. All observed irregularities appear to be anisotropic with axial ratios between 2:1 and 10:1. Ionospheric parameters vary with altitude and latitude. We conclude that the measured angular orientation of the anisotropic irregularities indicates magnetic field direction and may provide a basis for refining Jovian magnetic field models.

  3. Scintillations associated with bottomside sinusoidal irregularities in the equatorial F region

    Science.gov (United States)

    Basu, S.; Basu, S.; Valladares, C. E.; Dasgupta, A.; Whitney, H. E.

    1986-01-01

    Multisatellite scintillation observations and spaced receiver drift measurements are presented for a category of equatorial F region plasma irregularities characterized by nearly sinusoidal waveforms in the ion number density. The observations were made at Huancayo, Peru, and the measurements at Ancon, Peru, associated with irregularities observed by the Atmospheric-Explorer-E satellite on a few nights in December 1979. Utilizing ray paths to various geostationary satellites, it was found that the irregularities grow and decay almost simultaneously in long-lived patches extending at least 1000 km in the east-west direction.

  4. Capture of irregular satellites at Jupiter

    International Nuclear Information System (INIS)

    Nesvorný, David; Vokrouhlický, David; Deienno, Rogerio

    2014-01-01

    The irregular satellites of outer planets are thought to have been captured from heliocentric orbits. The exact nature of the capture process, however, remains uncertain. We examine the possibility that irregular satellites were captured from the planetesimal disk during the early solar system instability when encounters between the outer planets occurred. Nesvorný et al. already showed that the irregular satellites of Saturn, Uranus, and Neptune were plausibly captured during planetary encounters. Here we find that the current instability models present favorable conditions for capture of irregular satellites at Jupiter as well, mainly because Jupiter undergoes a phase of close encounters with an ice giant. We show that the orbital distribution of bodies captured during planetary encounters provides a good match to the observed distribution of irregular satellites at Jupiter. The capture efficiency for each particle in the original transplanetary disk is found to be (1.3-3.6) × 10 –8 . This is roughly enough to explain the observed population of jovian irregular moons. We also confirm Nesvorný et al.'s results for the irregular satellites of Saturn, Uranus, and Neptune.

  5. Formation of dwarf ellipticals and dwarf irregular galaxies by interaction of giant galaxies under environmental influence

    OpenAIRE

    Chattopadhyay, Tanuka; Debsarma, Suma; Karmakar, Pradip; Davoust, Emmanuel

    2014-01-01

    A model is proposed for the formation of gas-rich dwarf irregular galaxies and gas-poor, rotating dwarf elliptical galaxies following the interaction between two giant galaxies as a function of space density. The formation of dwarf galaxies is considered to depend on a random variable, the tidal index theta, an environmental parameter defined by Karachentsev et al. (2004), such that for theta less than zero, the formation of dwarf irregular galaxy is assured whereas for theta greater than zer...

  6. Low-density lipoprotein subfraction, carotid artery intima-media thickness, nitric oxide, and tumor necrosis factor alpha are associated with newly diagnosed ischemic stroke

    Directory of Open Access Journals (Sweden)

    Medine Cumhur Cure

    2013-01-01

    Full Text Available Objectives: Small dense (sd low-density lipoprotein (LDL, tumor necrosis factor (TNF alpha (a, and nitric oxide (NO have recently emerged as important stroke risk factors. The aim of the study was to investigate the effects of increased levels of small LDL particle size, TNF-a and NO on the developed ischemic stroke and increased carotid artery intima-media thickness (CIMT. Materials and Methods: A total of 29 women and 25 men (a total of 54 ischemic stroke patients and a similar age group of 50 controls (29 females and 21 males were included in the study. CIMT, C-reactive protein (CRP, TNF-a, NO, and lipid subfraction test of the two groups were measured. Results: The mean LDL particle size was smaller in patients with stroke than in the controls (26.8 ± 0.31 nm vs. 27.0 ± 0.31 nm, P = 0.003. sd-LDL, TNF-a, NO, CRP, right CIMT, and left CIMT were higher in patients with stroke than in the controls (respectively; 8.2 ± 7.8 mg/dL vs. 3.3 ± 3.5 mg/dL, P < 0.001;75.6 ± 25.0 pg/mL vs. 65.4 ± 9.1 pg/mL, P = 0.009;76.4 ± 53.3 mmol/L vs. 41.5 ± 27.0 mmol/L, P < 0.001;1.9 ± 2.6 mm vs. 0.4 ± 0.3 mm P < 0.001;0.97 ± 0.38 mm vs. 0.83 ± 0.15 mm, P = 0.007;1.04 ± 0.44 mm vs. 0.87 ± 0.19 mm, P = 0.010. Conclusion: These results show that sd-LDL is independently associated with the incidence of stroke and may be a risk factor in the development of stroke. In addition, TNF-a, NO, right CIMT, and left CIMT may be a risk factor in the development of ischemic stroke.

  7. Examining U.S. Irregular Warfare Doctrine

    National Research Council Canada - National Science Library

    Kimbrough, IV, James M

    2008-01-01

    ... of insurgency and terrorism. In response to the associated strategic challenges, a growing debate occurred among military historians, strategists, and leaders about the proper principles necessary for contemporary irregular...

  8. Locating irregularly shaped clusters of infection intensity

    Directory of Open Access Journals (Sweden)

    Niko Yiannakoulias

    2010-05-01

    Full Text Available Patterns of disease may take on irregular geographic shapes, especially when features of the physical environment influence risk. Identifying these patterns can be important for planning, and also identifying new environmental or social factors associated with high or low risk of illness. Until recently, cluster detection methods were limited in their ability to detect irregular spatial patterns, and limited to finding clusters that were roughly circular in shape. This approach has less power to detect irregularly-shaped, yet important spatial anomalies, particularly at high spatial resolutions. We employ a new method of finding irregularly-shaped spatial clusters at micro-geographical scales using both simulated and real data on Schistosoma mansoni and hookworm infection intensities. This method, which we refer to as the “greedy growth scan”, is a modification of the spatial scan method for cluster detection. Real data are based on samples of hookworm and S. mansoni from Kitengei, Makueni district, Kenya. Our analysis of simulated data shows how methods able to find irregular shapes are more likely to identify clusters along rivers than methods constrained to fixed geometries. Our analysis of infection intensity identifies two small areas within the study region in which infection intensity is elevated, possibly due to local features of the physical or social environment. Collectively, our results show that the “greedy growth scan” is a suitable method for exploratory geographical analysis of infection intensity data when irregular shapes are suspected, especially at micro-geographical scales.

  9. Backscatter measurements of 11-cm equatorial spread-F irregularities

    International Nuclear Information System (INIS)

    Tsunoda, R.T.

    1980-01-01

    In the equatorial F-region ionosphere, a turbulent cascade process has been found to exist that extends from irregularity spatial wavelengths longer than tens of kilometers down to wavelengths as short as 36 cm. To investigate the small-scale regime of wavelengths less than 36 cm, an equatorial radar experiment was conducted using a frequency of 1320 MHz that corresponds to an irregularity wavelength of 11 cm. The first observations of radar backscatter from 11-cm field-aligned irregularities (FAI) are described. These measurements extend the spatial wavelength regime of F-region FAI to lengths that approach both electron gyroradius and the Debye length. Agreement of these results with the theory of high-frequency drift waves suggests that these observations may be unique to the equatorial ionosphere. That is, the requirement of low electron densities for which the theroy calls may preclude the existence of 11-cm FAI elsewhere in the F-region ionosphere, except in equatorial plasma bubbles

  10. A final report to the Laboratory Directed Research and Development committee on Project 93-ERP-075: ''X-ray laser propagation and coherence: Diagnosing fast-evolving, high-density laser plasmas using X-ray lasers''

    International Nuclear Information System (INIS)

    Wan, A.S.; Cauble, R.; Da Silva, L.B.; Libby, S.B.; Moreno, J.C.

    1996-02-01

    This report summarizes the major accomplishments of this three-year Laboratory Directed Research and Development (LDRD) Exploratory Research Project (ERP) entitled ''X-ray Laser Propagation and Coherence: Diagnosing Fast-evolving, High-density Laser Plasmas Using X-ray Lasers,'' tracking code 93-ERP-075. The most significant accomplishment of this project is the demonstration of a new laser plasma diagnostic: a soft x-ray Mach-Zehnder interferometer using a neonlike yttrium x-ray laser at 155 angstrom as the probe source. Detailed comparisons of absolute two-dimensional electron density profiles obtained from soft x-ray laser interferograms and profiles obtained from radiation hydrodynamics codes, such as LASNEX, will allow us to validate and benchmark complex numerical models used to study the physics of laser-plasma interactions. Thus the development of soft x-ray interferometry technique provides a mechanism to probe the deficiencies of the numerical models and is an important tool for, the high-energy density physics and science-based stockpile stewardship programs. The authors have used the soft x-ray interferometer to study a number of high-density, fast evolving, laser-produced plasmas, such as the dynamics of exploding foils and colliding plasmas. They are pursuing the application of the soft x-ray interferometer to study ICF-relevant plasmas, such as capsules and hohlraums, on the Nova 10-beam facility. They have also studied the development of enhanced-coherence, shorter-pulse-duration, and high-brightness x-ray lasers. The utilization of improved x-ray laser sources can ultimately enable them to obtain three-dimensional holographic images of laser-produced plasmas

  11. Detecting chaos in irregularly sampled time series.

    Science.gov (United States)

    Kulp, C W

    2013-09-01

    Recently, Wiebe and Virgin [Chaos 22, 013136 (2012)] developed an algorithm which detects chaos by analyzing a time series' power spectrum which is computed using the Discrete Fourier Transform (DFT). Their algorithm, like other time series characterization algorithms, requires that the time series be regularly sampled. Real-world data, however, are often irregularly sampled, thus, making the detection of chaotic behavior difficult or impossible with those methods. In this paper, a characterization algorithm is presented, which effectively detects chaos in irregularly sampled time series. The work presented here is a modification of Wiebe and Virgin's algorithm and uses the Lomb-Scargle Periodogram (LSP) to compute a series' power spectrum instead of the DFT. The DFT is not appropriate for irregularly sampled time series. However, the LSP is capable of computing the frequency content of irregularly sampled data. Furthermore, a new method of analyzing the power spectrum is developed, which can be useful for differentiating between chaotic and non-chaotic behavior. The new characterization algorithm is successfully applied to irregularly sampled data generated by a model as well as data consisting of observations of variable stars.

  12. Irregular menstruation according to occupational status.

    Science.gov (United States)

    Kwak, Yeunhee; Kim, Yoonjung

    2017-07-06

    This cross-sectional study explored associations of irregular menstruation with occupational characteristics, using secondary analyses of data from 4,731 women aged 19-54 years, collected from a nationally representative sample, the Korea National Health and Nutrition Examination Survey-V during 2010-2012. The associations between irregular menstruation and occupation were explored using multiple logistic regression. Compared to non-manual workers, service/sales workers had a greater odds of irregular menstruation (adjusted odds ratio [aOR]: 1.44; 95percent confidence interval [CI]: 1.04-1.99) as did manual workers and unemployed women (aOR: 1.56; 95percent CI: 1.10-2.22, aOR: 1.46; 95percent CI: 1.14-1.89, respectively). Compared to regular workers, temporary workers and unemployed women had aORs of 1.52 (95percent CI: 1.08-2.13) and 1.33 (95percent CI: 1.05-1.69), respectively. Also, when compared to full-time workers, part-time workers and unemployed women had greater odds of irregular menstruation (aOR: 1.41; 95percent CI: 1.00-2.00 and aOR: 1.29; 95percent CI: 1.03-1.63, respectively). Furthermore, compared to daytime workers, shift workers and unemployed women had greater odds irregular menstruation (aOR: 1.39; 95percent CI: 1.03-1.88 and aOR: 1.28; 95percent CI: 1.04-1.59, respectively). Women with these occupational characteristics should be screened for early diagnosis and intervention for irregular menstruation.

  13. Advances in electron dosimetry of irregular fields

    International Nuclear Information System (INIS)

    Mendez V, J.

    1998-01-01

    In this work it is presented an advance in Electron dosimetry of irregular fields for beams emitted by linear accelerators. At present diverse methods exist which are coming to apply in the Radiotherapy centers. In this work it is proposed a method for irregular fields dosimetry. It will be allow to calculate the dose rate absorbed required for evaluating the time for the treatment of cancer patients. Utilizing the results obtained by the dosimetric system, it has been possible to prove the validity of the method describe for 12 MeV energy and for square field 7.5 x 7.5 cm 2 with percentile error less than 1 % . (Author)

  14. High energy model for irregular absorbing particles

    International Nuclear Information System (INIS)

    Chiappetta, Pierre.

    1979-05-01

    In the framework of a high energy formulation of relativistic quantum scattering a model is presented which describes the scattering functions and polarization of irregular absorbing particles, whose dimensions are greater than the incident wavelength. More precisely in the forward direction an amplitude parametrization of eikonal type is defined which generalizes the usual diffraction theory, and in the backward direction a reflective model is used including a shadow function. The model predictions are in good agreement with the scattering measurements off irregular compact and fluffy particles performed by Zerull, Giese and Weiss (1977)

  15. Stromal haze, myofibroblasts, and surface irregularity after PRK.

    Science.gov (United States)

    Netto, Marcelo V; Mohan, Rajiv R; Sinha, Sunilima; Sharma, Ajay; Dupps, William; Wilson, Steven E

    2006-05-01

    The aim of this study was to investigate the relationship between the level of stromal surface irregularity after photorefractive keratectomy (PRK) and myofibroblast generation along with the development of corneal haze. Variable levels of stromal surface irregularity were generated in rabbit corneas by positioning a fine mesh screen in the path of excimer laser during ablation for a variable percentage of the terminal pulses of the treatment for myopia that does not otherwise generate significant opacity. Ninety-six rabbits were divided into eight groups: [see table in text]. Slit lamp analysis and haze grading were performed in all groups. Rabbits were sacrificed at 4 hr or 4 weeks after surgery and histochemical analysis was performed on corneas for apoptosis (TUNEL assay), myofibroblast marker alpha-smooth muscle actin (SMA), and integrin alpha4 to delineate the epithelial basement membrane. Slit-lamp grading revealed severe haze formation in corneas in groups IV and VI, with significantly less haze in groups II, III, and VII and insignificant haze compared with the unwounded control in groups I and V. Analysis of SMA staining at 4 weeks after surgery, the approximate peak of haze formation in rabbits, revealed low myofibroblast formation in group I (1.2+/-0.2 cells/400x field) and group V (1.8+/-0.4), with significantly more in groups II (3.5+/-1.8), III (6.8+/-1.6), VII (7.9+/-3.8), IV (12.4+/-4.2) and VI (14.6+/-5.1). The screened groups were significantly different from each other (p PRK groups. The -9.0 diopter PRK group VI had significantly more myofibroblast generation than the -9.0 diopter PRK with PTK-smoothing group VII (p PRK and the level of stromal surface irregularity. PTK-smoothing with methylcellulose was an effective method to reduce stromal surface irregularity and decreased both haze and associated myofibroblast density. We hypothesize that stromal surface irregularity after PRK for high myopia results in defective basement membrane

  16. Synchronizing data from irregularly sampled sensors

    Science.gov (United States)

    Uluyol, Onder

    2017-07-11

    A system and method include receiving a set of sampled measurements for each of multiple sensors, wherein the sampled measurements are at irregular intervals or different rates, re-sampling the sampled measurements of each of the multiple sensors at a higher rate than one of the sensor's set of sampled measurements, and synchronizing the sampled measurements of each of the multiple sensors.

  17. Natural convection inside an irregular porous cavity

    International Nuclear Information System (INIS)

    Beltran, Jorge I. LLagostera; Trevisan, Osvair Vidal

    1990-01-01

    Natural convection flow induced by heating from below in a irregular porous cavity is investigated numerically. The influence of the modified Rayleigh number and geometric ratios on heat transfer and fluid flow is studied. Global and local Nusselt for Rayleigh numbers covering the range 0 - 1600 and for several geometric ratios. The fluid flow and the temperature field are illustrated by contour maps. (author)

  18. ON THE STAR FORMATION LAW FOR SPIRAL AND IRREGULAR GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Elmegreen, Bruce G., E-mail: bge@us.ibm.com [IBM Research Division, T.J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, NY 10598 (United States)

    2015-12-01

    A dynamical model for star formation on a galactic scale is proposed in which the interstellar medium is constantly condensing to star-forming clouds on the dynamical time of the average midplane density, and the clouds are constantly being disrupted on the dynamical timescale appropriate for their higher density. In this model, the areal star formation rate scales with the 1.5 power of the total gas column density throughout the main regions of spiral galaxies, and with a steeper power, 2, in the far outer regions and in dwarf irregular galaxies because of the flaring disks. At the same time, there is a molecular star formation law that is linear in the main and outer parts of disks and in dIrrs because the duration of individual structures in the molecular phase is also the dynamical timescale, canceling the additional 0.5 power of surface density. The total gas consumption time scales directly with the midplane dynamical time, quenching star formation in the inner regions if there is no accretion, and sustaining star formation for ∼100 Gyr or more in the outer regions with no qualitative change in gas stability or molecular cloud properties. The ULIRG track follows from high densities in galaxy collisions.

  19. Post-midnight equatorial irregularity distributions and vertical drift velocity variations during solstices

    Science.gov (United States)

    Su, S.-Y.; Liu, C. H.; Chao, C.-K.

    2018-04-01

    Longitudinal distributions of post-midnight equatorial ionospheric irregularity occurrences observed by ROCSAT-1 (1st satellite of the Republic of China) during moderate to high solar activity years in two solstices are studied with respect to the vertical drift velocity and density variations. The post-midnight irregularity distributions are found to be similar to the well-documented pre-midnight ones, but are different from some published distributions taken during solar minimum years. Even though the post-midnight ionosphere is sinking in general, longitudes of frequent positive vertical drift and high density seems to coincide with the longitudes of high irregularity occurrences. Large scatters found in the vertical drift velocity and density around the dip equator in different ROCSAT-1 orbits indicate the existence of large and frequent variations in the vertical drift velocity and density that seem to be able to provide sufficient perturbations for the Rayleigh-Taylor (RT) instability to cause the irregularity occurrences. The need of seeding agents such as gravity waves from atmospheric convective clouds to initiate the Rayleigh-Taylor instability may not be necessary.

  20. Analysis of the evolvement of contact wire wear irregularity in railway catenary based on historical data

    NARCIS (Netherlands)

    Wang, H.; Nunez Vicencio, Alfredo; Liu, Zhigang; Song, Yang; Duan, Fuchuan; Dollevoet, R.P.B.J.

    2017-01-01

    This paper studies the evolvement of the wear irregularity of contact wire using wire thickness data measured yearly from a section of railway catenary. The power spectral density and time–frequency representation based on the wavelet transform are employed for data analysis, with an emphasis on

  1. Fitting Irregular Shape Figures into Irregular Shape Areas for the Nesting Problem in the Leather Industry

    Directory of Open Access Journals (Sweden)

    Guevara-Palma Luis

    2015-01-01

    Full Text Available The nesting problem of irregular shapes within irregular areas has been studied from several approaches due to their application in different industries. The particular case of cutting leather involves several restrictions that add complexity to this problem, it is necessary to generate products that comply with the quality required by customers This paper presents a methodology for the accommodation of irregular shapes in an irregular area (leather considering the constraints set by the footwear industry, and the results of this methodology when applied by a computer system. The scope of the system is to develop a working prototype that operates under the guidelines of a commercial production line of a sponsor company. Preliminary results got a reduction of 70% of processing time and improvement of 5% to 7% of the area usage when compared with manual accommodation.

  2. Menstrual irregularity and poly cystic ovarian syndrome among adolescent girls--a 2 year follow-up study.

    Science.gov (United States)

    Nair, M K C; Pappachan, Princly; Balakrishnan, Sheila; Leena, M L; George, Babu; Russell, Paul S

    2012-01-01

    To study the clinical outcome after a gap of 2 years, among adolescent girls with confirmed menstrual irregularity and with or without ultrasound diagnosed polycystic ovaries. 136 adolescent girls from a cohort of 301 girls between 15 and 17 years of age with confirmed menstrual irregularity, with or without ultrasound diagnosed polycystic ovaries, were assessed in detail after a gap of 2 years. Present menstrual history and symptoms as well as signs of polycystic ovary syndrome (PCOS) were recorded, apart from ultrasound scanning of abdomen. PCOS was diagnosed using Rotterdam's consensus criteria and a comparative analysis was done among cases with and without PCOS. In the phase-II study done after a gap of 2 years, there was a statistically significant lower percentage of irregularities in menses, acne and enlarged thyroid, but a statistically significant increase in hirsuitism as compared to Phase-I study. Of the 136 cases reported, 36.0% cases were found to have PCOS and 63.9% cases were normal. Comparison of the two groups showed a statistically significant higher percentage difference in prevalence of irregular menses (59.9%), hirsuitism (56.3%), acne (17.8%), obesity (17.3%), polycystic ovaries on ultrasound (47.8%) and clinical hyperandrogenism (56.1%) among those with PCOS as against those without PCOS. The results of this study support screening for menstrual irregularity, obesity and signs of clinical hyperandrogenism for early diagnosis of PCOS in an effort to improve the reproductive health of adolescent girls.

  3. Generating Performance Models for Irregular Applications

    Energy Technology Data Exchange (ETDEWEB)

    Friese, Ryan D.; Tallent, Nathan R.; Vishnu, Abhinav; Kerbyson, Darren J.; Hoisie, Adolfy

    2017-05-30

    Many applications have irregular behavior --- non-uniform input data, input-dependent solvers, irregular memory accesses, unbiased branches --- that cannot be captured using today's automated performance modeling techniques. We describe new hierarchical critical path analyses for the \\Palm model generation tool. To create a model's structure, we capture tasks along representative MPI critical paths. We create a histogram of critical tasks with parameterized task arguments and instance counts. To model each task, we identify hot instruction-level sub-paths and model each sub-path based on data flow, instruction scheduling, and data locality. We describe application models that generate accurate predictions for strong scaling when varying CPU speed, cache speed, memory speed, and architecture. We present results for the Sweep3D neutron transport benchmark; Page Rank on multiple graphs; Support Vector Machine with pruning; and PFLOTRAN's reactive flow/transport solver with domain-induced load imbalance.

  4. Long wavelength irregularities in the equatorial electrojet

    OpenAIRE

    Kudeki, E.; Farley, D. T.; Fejer, Bela G.

    1982-01-01

    We have used the radar interferometer technique at Jicamarca to study in detail irregularities with wavelengths of a few kilometers generated in the unstable equatorial electrojet plasma during strong type 1 conditions. In-situ rocket observations of the same instability process are discussed in a companion paper. These large scale primary waves travel essentially horizontally and have large amplitudes. The vertical electron drift velocities driven by the horizontal wave electric fields reach...

  5. Improving Transactional Memory Performance for Irregular Applications

    OpenAIRE

    Pedrero, Manuel; Gutiérrez, Eladio; Romero, Sergio; Plata, Óscar

    2015-01-01

    Transactional memory (TM) offers optimistic concurrency support in modern multicore archi- tectures, helping the programmers to extract parallelism in irregular applications when data dependence information is not available before runtime. In fact, recent research focus on ex- ploiting thread-level parallelism using TM approaches. However, the proposed techniques are of general use, valid for any type of application. This work presents ReduxSTM, a software TM system specially d...

  6. Star formation histories of irregular galaxies

    International Nuclear Information System (INIS)

    Gallagher, J.S. III; Hunter, D.A.; Tutukov, A.V.

    1984-01-01

    We explore the star formation histories of a selection of irregular and spiral galaxies by using three parameters that sample the star formation rate (SFR) at different epochs: (1) the mass of a galaxy in the form of stars measures the SFR integrated over a galaxy's lifetime; (2) the blue luminosity is dominated primarily by stars formed over the past few billion years; and (3) Lyman continuum photon fluxes derived from Hα luminosities give the current ( 8 yr) SFR

  7. Parallel Computing Strategies for Irregular Algorithms

    Science.gov (United States)

    Biswas, Rupak; Oliker, Leonid; Shan, Hongzhang; Biegel, Bryan (Technical Monitor)

    2002-01-01

    Parallel computing promises several orders of magnitude increase in our ability to solve realistic computationally-intensive problems, but relies on their efficient mapping and execution on large-scale multiprocessor architectures. Unfortunately, many important applications are irregular and dynamic in nature, making their effective parallel implementation a daunting task. Moreover, with the proliferation of parallel architectures and programming paradigms, the typical scientist is faced with a plethora of questions that must be answered in order to obtain an acceptable parallel implementation of the solution algorithm. In this paper, we consider three representative irregular applications: unstructured remeshing, sparse matrix computations, and N-body problems, and parallelize them using various popular programming paradigms on a wide spectrum of computer platforms ranging from state-of-the-art supercomputers to PC clusters. We present the underlying problems, the solution algorithms, and the parallel implementation strategies. Smart load-balancing, partitioning, and ordering techniques are used to enhance parallel performance. Overall results demonstrate the complexity of efficiently parallelizing irregular algorithms.

  8. Extended Schmidt law holds for faint dwarf irregular galaxies

    Science.gov (United States)

    Roychowdhury, Sambit; Chengalur, Jayaram N.; Shi, Yong

    2017-12-01

    Context. The extended Schmidt law (ESL) is a variant of the Schmidt which relates the surface densities of gas and star formation, with the surface density of stellar mass added as an extra parameter. Although ESL has been shown to be valid for a wide range of galaxy properties, its validity in low-metallicity galaxies has not been comprehensively tested. This is important because metallicity affects the crucial atomic-to-molecular transition step in the process of conversion of gas to stars. Aims: We empirically investigate for the first time whether low metallicity faint dwarf irregular galaxies (dIrrs) from the local universe follow the ESL. Here we consider the "global" law where surface densities are averaged over the galactic discs. dIrrs are unique not only because they are at the lowest end of mass and star formation scales for galaxies, but also because they are metal-poor compared to the general population of galaxies. Methods: Our sample is drawn from the Faint Irregular Galaxy GMRT Survey (FIGGS) which is the largest survey of atomic hydrogen in such galaxies. The gas surface densities are determined using their atomic hydrogen content. The star formation rates are calculated using GALEX far ultraviolet fluxes after correcting for dust extinction, whereas the stellar surface densities are calculated using Spitzer 3.6 μm fluxes. The surface densities are calculated over the stellar discs defined by the 3.6 μm images. Results: We find dIrrs indeed follow the ESL. The mean deviation of the FIGGS galaxies from the relation is 0.01 dex, with a scatter around the relation of less than half that seen in the original relation. In comparison, we also show that the FIGGS galaxies are much more deviant when compared to the "canonical" Kennicutt-Schmidt relation. Conclusions: Our results help strengthen the universality of the ESL, especially for galaxies with low metallicities. We suggest that models of star formation in which feedback from previous generations

  9. The Impact of Irregular Warfare on the US Army

    National Research Council Canada - National Science Library

    McDonald, III, Roger L

    2006-01-01

    Although the U.S. Army has yet to clearly define irregular warfare, it is imperative that the Army take near-term action to enhance the ability of Soldiers and units to operate effectively in an irregular warfare environment...

  10. State reconstruction and irregular wavefunctions for the hydrogen atom

    Science.gov (United States)

    Krähmer, D. S.; Leonhardt, U.

    1997-07-01

    Inspired by a recently proposed procedure by Leonhardt and Raymer for wavepacket reconstruction, we calculate the irregular wavefunctions for the bound states of the Coulomb potential. We select the irregular solutions which have the simplest semiclassical limit.

  11. Manufacturing of Cast Metal Foams with Irregular Cell Structure

    Directory of Open Access Journals (Sweden)

    Kroupová I.

    2015-06-01

    Full Text Available Metallic foams are materials of which the research is still on-going, with the broad applicability in many different areas (e.g. automotive industry, building industry, medicine, etc.. These metallic materials have specific properties, such as large rigidity at low density, high thermal conductivity, capability to absorb energy, etc. The work is focused on the preparation of these materials using conventional casting technology (infiltration method, which ensures rapid and economically feasible method for production of shaped components. In the experimental part we studied conditions of casting of metallic foams with open pores and irregular cell structure made of ferrous and nonferrous alloys by use of various types of filler material (precursors.

  12. Method for hot pressing irregularly shaped refractory articles

    Science.gov (United States)

    Steinkamp, William E.; Ballard, Ambrose H.

    1982-01-01

    The present invention is directed to a method for hot pressing irregularly haped refractory articles with these articles of varying thickness being provided with high uniform density and dimensional accuracy. Two partially pressed compacts of the refractory material are placed in a die cavity between displaceable die punches having compact-contacting surfaces of the desired article configuration. A floating, rotatable block is disposed between the compacts. The displacement of the die punches towards one another causes the block to rotate about an axis normal to the direction of movement of the die punches to uniformly distribute the pressure loading upon the compacts for maintaining substantially equal volume displacement of the powder material during the hot pressing operation.

  13. Combined radar observations of equatorial electrojet irregularities at Jicamarca

    Directory of Open Access Journals (Sweden)

    D. L. Hysell

    2007-03-01

    Full Text Available Daytime equatorial electrojet plasma irregularities were investigated using five distinct radar diagnostics at Jicamarca including range-time-intensity (RTI mapping, Faraday rotation, radar imaging, oblique scattering, and multiple-frequency scattering using the new AMISR prototype UHF radar. Data suggest the existence of plasma density striations separated by 3–5 km and propagating slowly downward. The striations may be caused by neutral atmospheric turbulence, and a possible scenario for their formation is discussed. The Doppler shifts of type 1 echoes observed at VHF and UHF frequencies are compared and interpreted in light of a model of Farley Buneman waves based on kinetic ions and fluid electrons with thermal effects included. Finally, the up-down and east-west asymmetries evident in the radar observations are described and quantified.

  14. On irregularity strength of disjoint union of friendship graphs

    Directory of Open Access Journals (Sweden)

    Ali Ahmad

    2013-11-01

    Full Text Available We investigate the vertex total and edge total modication of the well-known irregularity strength of graphs. We have determined the exact values of the total vertex irregularity strength and the total edge irregularity strength of a disjoint union of friendship graphs.

  15. 16 CFR 501.6 - Cellulose sponges, irregular dimensions.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Cellulose sponges, irregular dimensions. 501... REQUIREMENTS AND PROHIBITIONS UNDER PART 500 § 501.6 Cellulose sponges, irregular dimensions. Variety packages of cellulose sponges of irregular dimensions, are exempted from the requirements of § 500.25 of this...

  16. Observations of inner plasmasphere irregularities with a satellite-beacon radio-interferometer array

    International Nuclear Information System (INIS)

    Jacobson, A.R.; Hoogeveen, G.; Carlos, R.C.; Wu, G.; Fejer, B.G.; Kelley, M.C.

    1996-01-01

    A radio-interferometer array illuminated by 136-MHz beacons of several geosynchronous satellites has been used to study small (≥10 13 m -2 ) transient disturbances in the total electron content along the lines of sight to the satellites. High-frequency (f>3 mHz) electron content oscillations are persistently observed, particularly during night and particularly during geomagnetically disturbed periods. The oscillations move across the array plane at speeds in the range 200 endash 2000 m/s, with propagation azimuths that are strongly peaked in lobes toward the western half-plane. Detailed analysis of this azimuth behavior, involving comparison between observations on various satellite positions, indicates compellingly that the phase oscillations originate in radio refraction due to geomagnetically aligned plasma density perturbations in the inner plasmasphere. The motion of the phase perturbations across the array plane is caused by EXB drift of the plasma medium in which the irregularities are embedded. We review the statistics of 2.5 years of around-the-clock data on the local time, magnetic disturbance, seasonal, and line-of-sight variations of these observed irregularities. We compare the irregularities close-quote inferred electrodynamic drifts to what is known about midlatitude plasma drift from incoherent scatter. Finally, we show in detail how the observation of these irregularities provides a unique and complementary monitor of inner plasmasphere irregularity incidence and zonal drift.copyright 1996 American Geophysical Union

  17. Locating irregularly shaped clusters of infection intensity

    DEFF Research Database (Denmark)

    Yiannakoulias, Niko; Wilson, Shona; Kariuki, H. Curtis

    2010-01-01

    of infection intensity identifies two small areas within the study region in which infection intensity is elevated, possibly due to local features of the physical or social environment. Collectively, our results show that the "greedy growth scan" is a suitable method for exploratory geographical analysis...... for cluster detection. Real data are based on samples of hookworm and S. mansoni from Kitengei, Makueni district, Kenya. Our analysis of simulated data shows how methods able to find irregular shapes are more likely to identify clusters along rivers than methods constrained to fixed geometries. Our analysis...

  18. Equatorial Ionospheric Irregularities Study from ROCSAT Data

    Science.gov (United States)

    2017-10-20

    UNLIMITED: PB Public Release 13. SUPPLEMENTARY NOTES 14. ABSTRACT Ionospheric irregularity/scintillation occurrences can be caused by external driving ...Academia Sinica, Taipei, Taiwan e-mail: chliu2@gate.sinica.edu.tw phone :886-3-4227151x34757 CoPI: Shin-Yi Su Institution: National Central...University, Chung-Li, Taiwan e-mail: sysu@csrsr.ncu.edu.tw phone :886-3-4227151x57643 CoPI: Lung-Chi Tsai Institution: National Central University, Chung-Li

  19. Density structures inside the plasmasphere: Cluster observations

    DEFF Research Database (Denmark)

    Darrouzet, F.; Decreau, P.M.E.; De Keyser, J.

    2004-01-01

    The electron density profiles derived from the EFW and WHISPER instruments on board the four Cluster spacecraft reveal density structures inside the plasmasphere and at its outer boundary, the plasmapause. We have conducted a statistical study to characterize these density structures. We focus...... on the plasmasphere crossing on I I April 2002, during which Cluster observed several density irregularities inside the plasmasphere, as well as a plasmaspheric plume. We derive the density gradient vectors from simultaneous density measurements by the four spacecraft. We also determine the normal velocity...... of the boundaries of the plume and of the irregularities from the time delays between those boundaries in the four individual density profiles, assuming they are planar. These new observations yield novel insights about the occurrence of density irregularities, their geometry and their dynamics. These in...

  20. Legal aspects of the EU policy on irregular immigration

    Directory of Open Access Journals (Sweden)

    Voinikov Vadim

    2015-12-01

    Full Text Available This article addresses the issues pertaining to the adoption and development of legislation on irregular migration in the context of uncontrolled growth in the number of immigrants from North Africa and the Middle East to the EU. The article attempts at studying the EU legislation on irregular migration, classifying it, and analysing the prospects of EU migration legislation in the light of an increase in irregular immigration into the EU. The author systematises, classifies the current EU legislation on irregular immigration, and analyses the conditions, in which this legislation was developed. Using the legislation analysis method, the author proposes the following system of EU legislation on irregular immigration: rules preventing assistance to irregular immigration, rules preventing employment of irregular immigrants, rules on the return of irregular migrants and readmission, rules on border control, and rules on collaboration with third countries. The author pays special attention to analysing the current state of irregular immigration to the EU, which was dubbed the ‘greatest migration crisis in Europe’. The conclusion is that the European Union succeeded in the development of pioneering legislation on irregular immigration, which can serve as the basis for reception by other states. However, changes in the political and economic situation in the EU’s southern borderlands made the current legal mechanisms incapable of withstanding new threats. It necessitates a radical reform of the legislation on irregular immigration.

  1. Pleural irregularities and mediastinal pleural involvement in early stages of malignant pleural mesothelioma and benign asbestos pleural effusion.

    Science.gov (United States)

    Kato, Katsuya; Gemba, Kenichi; Fujimoto, Nobukazu; Aoe, Keisuke; Takeshima, Yukio; Inai, Kouki; Kishimoto, Takumi

    2016-09-01

    To elucidate differences in the level and localization of pleural irregularities in early malignant pleural mesothelioma (eMPM) and benign asbestos pleural effusion (BAPE) using CT. Retrospective assessment of CT findings of consecutive patients with BAPE at a single centre and patients with eMPM reported in Japanese vital statistics. Thirty-six patients with confirmed diagnoses of BAPE and sixty-six patients with confirmed diagnoses of eMPM (mesothelioma stages T1 or T2) were included. Informed consent, CT scans, and clinical and pathologic details were obtained for all patients and were reviewed by one radiologist, two pathologists, and two pulmonologists. Asbestosis, pleural plaque, rounded atelectasis, and diffuse pleural thickening were assessed in all patients. Prevalence of asbestosis, pleural plaque, rounded atelectasis, and diffuse pleural thickening was significantly higher in the BAPE group. Low-level irregularity was more common in the BAPE group (ppleural irregularity was not observed in any patients in the BAPE group, although 55% of patients in the eMPM group showed interlobar pleural irregularity. Mediastinal pleural involvement was observed in 74% of patients in the eMPM group and had a positive predictive value of 89%. This study demonstrates that the level and localization of plural irregularities significantly differed between patients with BAPE and eMPM. Large-scale prospective studies are needed to fully establish the diagnostic utility of such differences. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  2. ARCAD3-SAFARI coordinated study of auroral and polar F-region ionospheric irregularities

    International Nuclear Information System (INIS)

    Villain, J.P.; Hanuise, C.; Beghin, C.

    1985-01-01

    Simultaneous observations of F-region ionospheric irregularities have been performed with the SAFARI ground based HF radars and the ISOPROBE experiment on board the AUREOL-3 satellite. Among seven orbits during which the satellite trajectory was directly in the radar beam or in the vicinity, four of them have been analysed in detail. The spectral power of the electron density variations ΔNe/Ne has been calculated for wavelengths between 20 m and 1 km from the ISOPROBE high time resolution thermal plasma measurements. One spectrum is obtained every 1.2 sec., which corresponds to about 10 km along the satellite trajectory. The SAFARI experiment is a set of two HF coherent radars located at Lycksele (Sweden) and Oulu (Finland). These radars are sensitive to F-region ionospheric irregularities of 10 m wavelength in the polar and auroral ionosphere. The phase velocity of the irregularities obtained from the Doppler spectrum is related to the ambient plasma drift. The presence of echoes observed with the SAFARI radars is compared with the spectral power of the electron density variations deduced from the ISOPROBE in-situ measurements. A good agreement is found between the two sets of observations and a numerical value of the spectral power corresponding to detection of echoes by the radar is given. A synoptical view of the event is given and interpreted according to the existing theories on plasma irregularities

  3. Experimental evidence of widespread regions of small-scale plasma irregularities in the magnetosphere

    International Nuclear Information System (INIS)

    Holmgren, G.; Kintner, P.M.

    1990-01-01

    Small-scale (≤ 1 km) plasma irregularities have previously been observed in situ from the E region to an altitude of 8,000 km. In this paper the authors report results from the Viking plasma wave experiments which extends the measurements of high-latitude irregularities in two ways: (1) they have acquired electron density fluctuation measurements up to an altitude of 13,500 km and (2) for the first time a measurement technique was used that made a phase velocity deduction possible from in situ measurements. The spacecraft was equipped with two spatially separated Langmuir probes, each with an ability to measure relative probe current fluctuations with frequencies from dc to about 400 Hz. Under certain assumptions the current fluctuations could be interpreted as relative plasma density fluctuations, δn e /n e . Data from this interferometric instrument has been used to infer the distribution and nature of plasma irregularities along Viking orbits. It is demonstrated that the interferometric technique offers great advantages compared to single point measurements in this kind of study. It is shown that the observed small-scale plasma irregularities are nondispersive and convecting with the background plasma. They exhibit a power law frequency spectrum as observed in the satellite reference frame. The spectral index varies with location. An attempt to map source regions by identifying regions of high power and shallow spectrums is made

  4. Diagnosing Tic Disorders

    Science.gov (United States)

    ... Submit" /> Information For… Media Policy Makers Diagnosing Tic Disorders Language: English (US) Español (Spanish) Recommend on ... or postviral encephalitis). Persistent (Chronic) Motor or Vocal Tic Disorder To be diagnosed with a persistent tic ...

  5. Computing proton dose to irregularly moving targets

    International Nuclear Information System (INIS)

    Phillips, Justin; Gueorguiev, Gueorgui; Grassberger, Clemens; Dowdell, Stephen; Paganetti, Harald; Sharp, Gregory C; Shackleford, James A

    2014-01-01

    Purpose: While four-dimensional computed tomography (4DCT) and deformable registration can be used to assess the dose delivered to regularly moving targets, there are few methods available for irregularly moving targets. 4DCT captures an idealized waveform, but human respiration during treatment is characterized by gradual baseline shifts and other deviations from a periodic signal. This paper describes a method for computing the dose delivered to irregularly moving targets based on 1D or 3D waveforms captured at the time of delivery. Methods: The procedure uses CT or 4DCT images for dose calculation, and 1D or 3D respiratory waveforms of the target position at time of delivery. Dose volumes are converted from their Cartesian geometry into a beam-specific radiological depth space, parameterized in 2D by the beam aperture, and longitudinally by the radiological depth. In this new frame of reference, the proton doses are translated according to the motion found in the 1D or 3D trajectory. These translated dose volumes are weighted and summed, then transformed back into Cartesian space, yielding an estimate of the dose that includes the effect of the measured breathing motion. The method was validated using a synthetic lung phantom and a single representative patient CT. Simulated 4DCT was generated for the phantom with 2 cm peak-to-peak motion. Results: A passively-scattered proton treatment plan was generated using 6 mm and 5 mm smearing for the phantom and patient plans, respectively. The method was tested without motion, and with two simulated breathing signals: a 2 cm amplitude sinusoid, and a 2 cm amplitude sinusoid with 3 cm linear drift in the phantom. The tumor positions were equally weighted for the patient calculation. Motion-corrected dose was computed based on the mid-ventilation CT image in the phantom and the peak exhale position in the patient. Gamma evaluation was 97.8% without motion, 95.7% for 2 cm sinusoidal motion, 95.7% with 3 cm drift in

  6. Propagating star formation and irregular structure in spiral galaxies

    International Nuclear Information System (INIS)

    Mueller, M.W.; Arnett, W.D.

    1976-01-01

    A simple model is proposed which describes the irregular optical appearance often seen in late-type spiral galaxies. If high-mass stars produce spherical shock waves which induce star formation, new high-mass stars will be born which, in turn, produce new shock waves. When this process operates in a differentially rotating disk, our numerical model shows that large-scale spiral-shaped regions of star formation are built up. The structure is seen to be most sensitive to a parameter which governs how often a region of the interstellar medium can undergo star formation. For a proper choice of this parameter, large-scale features disappear before differential rotation winds them up. New spiral features continuously form, so some spiral structure is seen indefinitely. The structure is not the classical two-armed symmetric spiral pattern which the density-wave theory attempts to explain, but it is asymmetric and disorderly.The mechanism of propagating star formation used in our model is consistent with observations which connect young OB associations with expanding shells of gas. We discuss the possible interaction of this mechanism with density waves

  7. Long wavelength irregularities in the equatorial electrojet

    International Nuclear Information System (INIS)

    Kudeki, E.; Farley, D.T.; Fejer, B.G.

    1982-01-01

    We have used the radar interferometer technique at Jicamarca to study in detail irregularities with wavelengths of a few kilometers generated in the unstable equatorial electrojet plasma during strong type 1 conditions. In-situ rocket observations of the same instability process are discussed in a companion paper. These large scale primary waves travel essentially horizontally and have large amplitudes. The vertical electron drift velocities driven by the horizontal wave electric fields reach or exceed the ion-acoustic velocity even though the horizontal phase velocity of the wave is considerably smaller. A straightforward extension to the long wavelength regime of the usual linear theory of the electrojet instability explains this and several other observed features of these dominant primary waves

  8. Irregular employment amongst migrants in Spanish cities.

    Science.gov (United States)

    Sole, C; Ribas, N; Bergalli, V; Parella, S

    1998-04-01

    This article presents the irregular employment situation of non-European union immigrants in Spanish cities. Foreign labor is remarkable for its heterogeneity in terms of country of origin, demographic characteristics, and the different ways in which immigrants have entered the job market. Legal immigrants tend to concentrate in five different branches of activity, such as domestic service (mostly women), hotel and restaurant industry, agriculture, building and retail trade. Migrants who work in agriculture suffer the worst labor conditions than all other migrants. However, all migrants experience difficulty in obtaining residency and labor permits. Four integration strategies among Moroccan immigrants in Catalonia are discussed and can be viewed as support networks of the immigrants.

  9. Characterization of Nightside Mid-latitude Irregularities Observed with the Blackstone SuperDARN Radar

    Science.gov (United States)

    Ruohoniemi, J. M.; Ribeiro, A. J.; Baker, J. B.; Greenwald, R. A.; Newell, P. T.

    2009-12-01

    The new mid-latitude SuperDARN radars at Wallops Island and Blackstone observe strong coherent backscattering on an almost nightly basis from latitudes that appear to be subauroral. One study has demonstrated an excellent correlation with the occurrence of density and temperature gradients within the ionospheric projection of the plasmapause (Greenwald et al., Geophys. Res. Lett. [2006]). We have processed all the data collected with the Blackstone radar since its inception in February 2008 for a characterization of the occurrence and properties of ‘plasmapause’ scatter. We have determined the local time and Kp dependencies of the activity and the relation of the spatial distribution of the irregularities to magnetospheric boundaries and ionospheric density gradients. We establish that the irregularities are a feature of the quiet-time subauroral ionosphere and provide a valuable diagnostic of the electric fields in the inner magnetosphere.

  10. Irregular activity arises as a natural consequence of synaptic inhibition

    International Nuclear Information System (INIS)

    Terman, D.; Rubin, J. E.; Diekman, C. O.

    2013-01-01

    Irregular neuronal activity is observed in a variety of brain regions and states. This work illustrates a novel mechanism by which irregular activity naturally emerges in two-cell neuronal networks featuring coupling by synaptic inhibition. We introduce a one-dimensional map that captures the irregular activity occurring in our simulations of conductance-based differential equations and mathematically analyze the instability of fixed points corresponding to synchronous and antiphase spiking for this map. We find that the irregular solutions that arise exhibit expansion, contraction, and folding in phase space, as expected in chaotic dynamics. Our analysis shows that these features are produced from the interplay of synaptic inhibition with sodium, potassium, and leak currents in a conductance-based framework and provides precise conditions on parameters that ensure that irregular activity will occur. In particular, the temporal details of spiking dynamics must be present for a model to exhibit this irregularity mechanism and must be considered analytically to capture these effects

  11. Irregular activity arises as a natural consequence of synaptic inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Terman, D., E-mail: terman@math.ohio-state.edu [Department of Mathematics, The Ohio State University, Columbus, Ohio 43210 (United States); Rubin, J. E., E-mail: jonrubin@pitt.edu [Department of Mathematics, University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States); Diekman, C. O., E-mail: diekman@njit.edu [Department of Mathematical Sciences, New Jersey Institute of Technology, Newark, New Jersey 07102 (United States)

    2013-12-15

    Irregular neuronal activity is observed in a variety of brain regions and states. This work illustrates a novel mechanism by which irregular activity naturally emerges in two-cell neuronal networks featuring coupling by synaptic inhibition. We introduce a one-dimensional map that captures the irregular activity occurring in our simulations of conductance-based differential equations and mathematically analyze the instability of fixed points corresponding to synchronous and antiphase spiking for this map. We find that the irregular solutions that arise exhibit expansion, contraction, and folding in phase space, as expected in chaotic dynamics. Our analysis shows that these features are produced from the interplay of synaptic inhibition with sodium, potassium, and leak currents in a conductance-based framework and provides precise conditions on parameters that ensure that irregular activity will occur. In particular, the temporal details of spiking dynamics must be present for a model to exhibit this irregularity mechanism and must be considered analytically to capture these effects.

  12. Finite Length Analysis of Irregular Repetition Slotted ALOHA in the Waterfall Region

    OpenAIRE

    Amat, Alexandre Graell i; Liva, Gianluigi

    2018-01-01

    A finite length analysis is introduced for irregular repetition slotted ALOHA (IRSA) that enables to accurately estimate its performance in the moderate-to-high packet loss probability regime, i.e., in the so-called waterfall region. The analysis is tailored to the collision channel model, which enables mapping the description of the successive interference cancellation process onto the iterative erasure decoding of low-density parity-check codes. The analysis provides accurate estimates of t...

  13. Report on the HAARP 2008 Winter Campaign Focusing on Artificial Ionospheric Irregularities

    Science.gov (United States)

    2008-07-31

    Figure Bl. Magnetic field variations recorded by the fluxgate magnetometer 30 Figure B2. Composite ionogram showing the variation of the reflection...variation was monitored by the Fluxgate Magnetometer . The density irregularities were monitored by the Ionosonde. 20:00 Preliminary Results The...magnetic field variations in three directions (H, D, and Z) recorded by the fluxgate magnetometer from UTC 20:00 to 04:00 are shown in the plots of

  14. Decomposing Oriented Graphs into Six Locally Irregular Oriented Graphs

    DEFF Research Database (Denmark)

    Bensmail, Julien; Renault, Gabriel

    2016-01-01

    An undirected graph G is locally irregular if every two of its adjacent vertices have distinct degrees. We say that G is decomposable into k locally irregular graphs if there exists a partition E1∪E2∪⋯∪Ek of the edge set E(G) such that each Ei induces a locally irregular graph. It was recently co...

  15. Characteristics of ionospheric irregularities causing scintillations at VHF/UHF

    International Nuclear Information System (INIS)

    Vats, H.O.; Deshpande, M.R.; Rastogi, R.G.

    1978-01-01

    Some properties of ionization irregularities using amplitude scintillation records of radio beacons from ATS-6 (phase II) at Ootacamund, India have been investigated. For the estimation of scale-size and strength of the irregularities a simple diffraction model has been used which explains only weak and moderate equatorial scintillation observations. It was found that the scale sizes of day time E-region irregularities are smaller than those in the F-region during night time in addition, irregularities are generated initially at large scale sizes which later break up into smaller scale sizes

  16. Advances in electron dosimetry of irregular fields; Avances en dosimetria de electrones de campos irregulares

    Energy Technology Data Exchange (ETDEWEB)

    Mendez V, J. [Departamento de Radioterapia, Instituto de Enfermedades Neoplasicas, Avenida Angamos Este 2520, Lima 34 (Peru)

    1998-12-31

    In this work it is presented an advance in Electron dosimetry of irregular fields for beams emitted by linear accelerators. At present diverse methods exist which are coming to apply in the Radiotherapy centers. In this work it is proposed a method for irregular fields dosimetry. It will be allow to calculate the dose rate absorbed required for evaluating the time for the treatment of cancer patients. Utilizing the results obtained by the dosimetric system, it has been possible to prove the validity of the method describe for 12 MeV energy and for square field 7.5 x 7.5 cm{sup 2} with percentile error less than 1 % . (Author)

  17. Irregular Saturnian Moon Lightcurves from Cassini-ISS Observations: Update

    Science.gov (United States)

    Denk, Tilmann; Mottola, S.

    2013-10-01

    Cassini ISS-NAC observations of the irregular moons of Saturn revealed various physical information on these objects. 16 synodic rotational periods: Hati (S43): 5.45 h; Mundilfari (S25): 6.74 h; Suttungr (S23): ~7.4 h; Kari (S45): 7.70 h; Siarnaq (S29): 10.14 h; Tarvos (S21): 10.66 h; Ymir (S19, sidereal period): 11.92220 h ± 0.1 s; Skathi (S27): ~12 h; Hyrrokkin (S44): 12.76 h; Ijiraq (S22): 13.03 h; Albiorix (S26): 13.32 h; Bestla (S39): 14.64 h; Bebhionn (S37): ~15.8 h; Kiviuq (S24): 21.82 h; Thrymr (S30): ~27 h; Erriapus (S28): ~28 h. The average period for the prograde-orbiting moons is ~16 h, for the retrograde moons ~11½ h (includes Phoebe's 9.2735 h from Bauer et al., AJ, 2004). Phase-angle dependent behavior of lightcurves: The phase angles of the observations range from 2° to 105°. The lightcurves which were obtained at low phase (<40°) show the 2-maxima/ 2-minima pattern expected for this kind of objects. At higher phases, more complicated lightcurves emerge, giving rough indications on shapes. Ymir pole and shape: For satellite Ymir, a convex-hull shape model and the pole-axis orientation have been derived. Ymir's north pole points toward λ = 230°±180°, β = -85°±10°, or RA = 100°±20°, Dec = -70°±10°. This is anti-parallel to the rotation axes of the major planets, indicating that Ymir not just orbits, but also rotates in a retrograde sense. The shape of Ymir resembles a triangular prism with edge lengths of ~20, ~24, and ~25 km. The ratio between the longest 25 km) and shortest axis (pole axis, ~15 km) is ~1.7. Erriapus seasons: The pole direction of object Erriapus has probably a low ecliptic latitude. This gives this moon seasons similar to the Uranian regular moons with periods where the sun stands very high in the sky over many years, and with years-long periods of permanent night. Hati density: The rotational frequency of the fastest rotator (Hati) is close to the frequency where the object would lose material from the surface if

  18. Ionospheric irregularities at low latitudes in the American sector

    International Nuclear Information System (INIS)

    Nakamura, Y.

    1981-10-01

    A detailed analysis of the atomic oxigem airglow emission at the wavelength of 6300 A observed at Cachoeira Paulista (22 0 41'S, 45 0 00'W) shows that intensity perturbations frequently occur and propagate from north to south and from west to east. Such irregularities originated in the ionospheric F region and occur essencially during the premidnight period. These perturbations have a high frequency of occurrence during spring and summer and are rare during winter and fall. The disturbances are correlated with range type spread F detected over Cachoeira Paulista, and have characteristics similar to equatorial ionospheric plasma bubbles (i.e., similar seazonal variation, time of occurrence, ionogram signatures, direction and speed of propagation, etc.). A numerical simulation is carried out for the generation and evolution of ionospheric bubbles based on the theory of the collisional Rayleigh-Taylor instability for the equatorial and Cachoeira Paulista regions. Also a study was made of the, evolution of the bubble as a function of the electron density profile and as a function of the amplitude of the initial density perturbation. Assuming the electron density profile perturbed by the bubble, the [OI] 6300 A intensity was calculated for various latitudes arbitrarily taken within the photometer scanning range. The bubble was assumed to be aligned with the Earth's magnetic field and extending from higher altitudes at the equatorial region down to be arbitrary height of 150 Km at which a negligible conductivity is assumed. It was also assumed that the bubble was moving upwards with the velocity of 120 m/s, which in turn was estimated from initial numerical simulation results. The airglow calculation results show that as the bubble goes up, the disturbances in the airglow intensity propagate from north to south, in accord with observed experimental results. (Author) [pt

  19. Two media method for linear attenuation coefficient determination of irregular soil samples

    International Nuclear Information System (INIS)

    Vici, Carlos Henrique Georges

    2004-01-01

    In several situations of nuclear applications, the knowledge of gamma-ray linear attenuation coefficient for irregular samples is necessary, such as in soil physics and geology. This work presents the validation of a methodology for the determination of the linear attenuation coefficient (μ) of irregular shape samples, in such a way that it is not necessary to know the thickness of the considered sample. With this methodology irregular soil samples (undeformed field samples) from Londrina region, north of Parana were studied. It was employed the two media method for the μ determination. It consists of the μ determination through the measurement of a gamma-ray beam attenuation by the sample sequentially immersed in two different media, with known and appropriately chosen attenuation coefficients. For comparison, the theoretical value of μ was calculated by the product of the mass attenuation coefficient, obtained by the WinXcom code, and the measured value of the density sample. This software employs the chemical composition of the samples and supplies a table of the mass attenuation coefficients versus the photon energy. To verify the validity of the two media method, compared with the simple gamma ray transmission method, regular pome stone samples were used. With these results for the attenuation coefficients and their respective deviations, it was possible to compare the two methods. In this way we concluded that the two media method is a good tool for the determination of the linear attenuation coefficient of irregular materials, particularly in the study of soils samples. (author)

  20. Irregular radiation response of a chondrosarcoma

    International Nuclear Information System (INIS)

    Marsden, J.J.; Kember, N.F.; Shaw, J.E.H.

    1980-01-01

    The DC II mouse chondrosarcoma was shown to be a potentially valuable radiobiological tumour system since it recovered from radiation injury by regrowth from clones that could be counted in histological sections. Unfortunately, the normal growth of this tumour following s.c. implantation in the thigh was irregular both in the time before growth became evident and in the rate of growth. The response to radiation was also unreliable since tumours irradiated with the same dose (e.g. 30 Gy) showed a range of responses from shrinkage to no detectable change in growth rate. The delay in normal growth can be attributed largely to delays in vascularization while changes in growth rate may be explained by differences in tumour architecture. Radiation response may depend on variations in hypoxic fraction and in relative cellularity. Tumours having the same external dimensions may differ by a factor of 80 in the numbers of tumour cells they contain. This chondrosarcoma may prove a closer model to some human tumours than many transplantable tumours that display regular growth patterns. (author)

  1. Regularities and irregularities in order flow data

    Science.gov (United States)

    Theissen, Martin; Krause, Sebastian M.; Guhr, Thomas

    2017-11-01

    We identify and analyze statistical regularities and irregularities in the recent order flow of different NASDAQ stocks, focusing on the positions where orders are placed in the order book. This includes limit orders being placed outside of the spread, inside the spread and (effective) market orders. Based on the pairwise comparison of the order flow of different stocks, we perform a clustering of stocks into groups with similar behavior. This is useful to assess systemic aspects of stock price dynamics. We find that limit order placement inside the spread is strongly determined by the dynamics of the spread size. Most orders, however, arrive outside of the spread. While for some stocks order placement on or next to the quotes is dominating, deeper price levels are more important for other stocks. As market orders are usually adjusted to the quote volume, the impact of market orders depends on the order book structure, which we find to be quite diverse among the analyzed stocks as a result of the way limit order placement takes place.

  2. Evaporation From Soil Containers With Irregular Shapes

    Science.gov (United States)

    Assouline, Shmuel; Narkis, Kfir

    2017-11-01

    Evaporation from bare soils under laboratory conditions is generally studied using containers of regular shapes where the vertical edges are parallel to the flow lines in the drying domain. The main objective of this study was to investigate the impact of irregular container shapes, for which the flow lines either converge or diverge toward the surface. Evaporation from initially saturated sand and sandy loam soils packed in cones and inverted cones was compared to evaporation from corresponding cylindrical columns. The initial evaporation rate was higher in the cones, and close to potential evaporation. At the end of the experiment, the cumulative evaporation depth in the sand cone was equal to that in the column but higher than in the inverted cone, while in the sandy loam, the order was cone > column > inverted cone. By comparison to the column, stage 1 evaporation was longer in the cones, and practically similar in the inverted cones. Stage 2 evaporation rate decreased with the increase of the evaporating surface area. These results were more pronounced in the sandy loam. For the sand column, the transition between stage 1 and stage 2 evaporation occurred when the depth of the saturation front was approximately equal to the characteristic length of the soil. However, for the cone and the inverted cone, it occurred for a shallower depth of the saturation front. It seems therefore that the concept of the characteristic length derived from the soil hydraulic properties is related to drying systems of regular shapes.

  3. Design strategies for irregularly adapting parallel applications

    International Nuclear Information System (INIS)

    Oliker, Leonid; Biswas, Rupak; Shan, Hongzhang; Sing, Jaswinder Pal

    2000-01-01

    Achieving scalable performance for dynamic irregular applications is eminently challenging. Traditional message-passing approaches have been making steady progress towards this goal; however, they suffer from complex implementation requirements. The use of a global address space greatly simplifies the programming task, but can degrade the performance of dynamically adapting computations. In this work, we examine two major classes of adaptive applications, under five competing programming methodologies and four leading parallel architectures. Results indicate that it is possible to achieve message-passing performance using shared-memory programming techniques by carefully following the same high level strategies. Adaptive applications have computational work loads and communication patterns which change unpredictably at runtime, requiring dynamic load balancing to achieve scalable performance on parallel machines. Efficient parallel implementations of such adaptive applications are therefore a challenging task. This work examines the implementation of two typical adaptive applications, Dynamic Remeshing and N-Body, across various programming paradigms and architectural platforms. We compare several critical factors of the parallel code development, including performance, programmability, scalability, algorithmic development, and portability

  4. Multiresolution Analysis Adapted to Irregularly Spaced Data

    Directory of Open Access Journals (Sweden)

    Anissa Mokraoui

    2009-01-01

    Full Text Available This paper investigates the mathematical background of multiresolution analysis in the specific context where the signal is represented by irregularly sampled data at known locations. The study is related to the construction of nested piecewise polynomial multiresolution spaces represented by their corresponding orthonormal bases. Using simple spline basis orthonormalization procedures involves the construction of a large family of orthonormal spline scaling bases defined on consecutive bounded intervals. However, if no more additional conditions than those coming from multiresolution are imposed on each bounded interval, the orthonormal basis is represented by a set of discontinuous scaling functions. The spline wavelet basis also has the same problem. Moreover, the dimension of the corresponding wavelet basis increases with the spline degree. An appropriate orthonormalization procedure of the basic spline space basis, whatever the degree of the spline, allows us to (i provide continuous scaling and wavelet functions, (ii reduce the number of wavelets to only one, and (iii reduce the complexity of the filter bank. Examples of the multiresolution implementations illustrate that the main important features of the traditional multiresolution are also satisfied.

  5. Resolution optimization with irregularly sampled Fourier data

    International Nuclear Information System (INIS)

    Ferrara, Matthew; Parker, Jason T; Cheney, Margaret

    2013-01-01

    Image acquisition systems such as synthetic aperture radar (SAR) and magnetic resonance imaging often measure irregularly spaced Fourier samples of the desired image. In this paper we show the relationship between sample locations, their associated backprojection weights, and image resolution as characterized by the resulting point spread function (PSF). Two new methods for computing data weights, based on different optimization criteria, are proposed. The first method, which solves a maximal-eigenvector problem, optimizes a PSF-derived resolution metric which is shown to be equivalent to the volume of the Cramer–Rao (positional) error ellipsoid in the uniform-weight case. The second approach utilizes as its performance metric the Frobenius error between the PSF operator and the ideal delta function, and is an extension of a previously reported algorithm. Our proposed extension appropriately regularizes the weight estimates in the presence of noisy data and eliminates the superfluous issue of image discretization in the choice of data weights. The Frobenius-error approach results in a Tikhonov-regularized inverse problem whose Tikhonov weights are dependent on the locations of the Fourier data as well as the noise variance. The two new methods are compared against several state-of-the-art weighting strategies for synthetic multistatic point-scatterer data, as well as an ‘interrupted SAR’ dataset representative of in-band interference commonly encountered in very high frequency radar applications. (paper)

  6. Irregular Homogeneity Domains in Ternary Intermetallic Systems

    Directory of Open Access Journals (Sweden)

    Jean-Marc Joubert

    2015-12-01

    Full Text Available Ternary intermetallic A–B–C systems sometimes have unexpected behaviors. The present paper examines situations in which there is a tendency to simultaneously form the compounds ABx, ACx and BCx with the same crystal structure. This causes irregular shapes of the phase homogeneity domains and, from a structural point of view, a complete reversal of site occupancies for the B atom when crossing the homogeneity domain. This work reviews previous studies done in the systems Fe–Nb–Zr, Hf–Mo–Re, Hf–Re–W, Mo–Re–Zr, Re–W–Zr, Cr–Mn–Si, Cr–Mo–Re, and Mo–Ni–Re, and involving the topologically close-packed Laves, χ and σ phases. These systems have been studied using ternary isothermal section determination, DFT calculations, site occupancy measurement using joint X-ray, and neutron diffraction Rietveld refinement. Conclusions are drawn concerning this phenomenon. The paper also reports new experimental or calculated data on Co–Cr–Re and Fe–Nb–Zr systems.

  7. 14 CFR 135.65 - Reporting mechanical irregularities.

    Science.gov (United States)

    2010-01-01

    ... irregularities and their correction. (b) The pilot in command shall enter or have entered in the aircraft maintenance log each mechanical irregularity that comes to the pilot's attention during flight time. Before each flight, the pilot in command shall, if the pilot does not already know, determine the status of...

  8. Uniform irradiation of irregularly shaped cavities for photodynamic therapy

    NARCIS (Netherlands)

    Rem, A. I.; van Gemert, M. J.; van der Meulen, F. W.; Gijsbers, G. H.; Beek, J. F.

    1997-01-01

    It is difficult to achieve a uniform light distribution in irregularly shaped cavities. We have conducted a study on the use of hollow 'integrating' moulds for more uniform light delivery of photodynamic therapy in irregularly shaped cavities such as the oral cavity. Simple geometries such as a

  9. Software support for irregular and loosely synchronous problems

    Science.gov (United States)

    Choudhary, A.; Fox, G.; Hiranandani, S.; Kennedy, K.; Koelbel, C.; Ranka, S.; Saltz, J.

    1992-01-01

    A large class of scientific and engineering applications may be classified as irregular and loosely synchronous from the perspective of parallel processing. We present a partial classification of such problems. This classification has motivated us to enhance FORTRAN D to provide language support for irregular, loosely synchronous problems. We present techniques for parallelization of such problems in the context of FORTRAN D.

  10. Regularisation of irregular verbs in child English second language ...

    African Journals Online (AJOL)

    Data was collected from the language of English medium preschool children. The study concludes that when the Blocking Principle interferes, children resort to a novel interlanguage rule that regularises irregular verbs. This interlanguage rule applies in a similar way to all irregular verbs, thus children produce utterances ...

  11. Weighted statistical parameters for irregularly sampled time series

    Science.gov (United States)

    Rimoldini, Lorenzo

    2014-01-01

    Unevenly spaced time series are common in astronomy because of the day-night cycle, weather conditions, dependence on the source position in the sky, allocated telescope time and corrupt measurements, for example, or inherent to the scanning law of satellites like Hipparcos and the forthcoming Gaia. Irregular sampling often causes clumps of measurements and gaps with no data which can severely disrupt the values of estimators. This paper aims at improving the accuracy of common statistical parameters when linear interpolation (in time or phase) can be considered an acceptable approximation of a deterministic signal. A pragmatic solution is formulated in terms of a simple weighting scheme, adapting to the sampling density and noise level, applicable to large data volumes at minimal computational cost. Tests on time series from the Hipparcos periodic catalogue led to significant improvements in the overall accuracy and precision of the estimators with respect to the unweighted counterparts and those weighted by inverse-squared uncertainties. Automated classification procedures employing statistical parameters weighted by the suggested scheme confirmed the benefits of the improved input attributes. The classification of eclipsing binaries, Mira, RR Lyrae, Delta Cephei and Alpha2 Canum Venaticorum stars employing exclusively weighted descriptive statistics achieved an overall accuracy of 92 per cent, about 6 per cent higher than with unweighted estimators.

  12. Irregular conformal block, spectral curve and flow equations

    International Nuclear Information System (INIS)

    Choi, Sang Kwan; Rim, Chaiho; Zhang, Hong

    2016-01-01

    Irregular conformal block is motivated by the Argyres-Douglas type of N=2 super conformal gauge theory. We investigate the classical/NS limit of irregular conformal block using the spectral curve on a Riemann surface with irregular punctures, which is equivalent to the loop equation of irregular matrix model. The spectral curve is reduced to the second order (Virasoro symmetry, SU(2) for the gauge theory) and third order (W_3 symmetry, SU(3)) differential equations of a polynomial with finite degree. The conformal and W symmetry generate the flow equations in the spectral curve and determine the irregular conformal block, hence the partition function of the Argyres-Douglas theory ala AGT conjecture.

  13. Irregular Morphing for Real-Time Rendering of Large Terrain

    Directory of Open Access Journals (Sweden)

    S. Kalem

    2016-06-01

    Full Text Available The following paper proposes an alternative approach to the real-time adaptive triangulation problem. A new region-based multi-resolution approach for terrain rendering is described which improves on-the-fly the distribution of the density of triangles inside the tile after selecting appropriate Level-Of-Detail by an adaptive sampling. This proposed approach organizes the heightmap into a QuadTree of tiles that are processed independently. This technique combines the benefits of both Triangular Irregular Network approach and region-based multi-resolution approach by improving the distribution of the density of triangles inside the tile. Our technique morphs the initial regular grid of the tile to deformed grid in order to minimize approximation error. The proposed technique strives to combine large tile size and real-time processing while guaranteeing an upper bound on the screen space error. Thus, this approach adapts terrain rendering process to local surface characteristics and enables on-the-fly handling of large amount of terrain data. Morphing is based-on the multi-resolution wavelet analysis. The use of the D2WT multi-resolution analysis of the terrain height-map speeds up processing and permits to satisfy an interactive terrain rendering. Tests and experiments demonstrate that Haar B-Spline wavelet, well known for its properties of localization and its compact support, is suitable for fast and accurate redistribution. Such technique could be exploited in client-server architecture for supporting interactive high-quality remote visualization of very large terrain.

  14. TINITALY/01: a new Triangular Irregular Network of Italy

    Directory of Open Access Journals (Sweden)

    M. T. Pareschi

    2007-06-01

    Full Text Available A new Digital Elevation Model (DEM of the natural landforms of Italy is presented. A methodology is discussed to build a DEM over wide areas where elevation data from non-homogeneous (in density and accuracy input sources are available. The input elevation data include contour lines and spot heights derived from the Italian Regional topographic maps, satellite-based global positioning system points, ground based and radar altimetry data. Owing to the great heterogeneity of the input data density, the DEM format that better preserves the original accuracy is a Triangular Irregular Network (TIN. A Delaunay-based TIN structure is improved by using the DEST algorithm that enhances input data by evaluating inferred break-lines. Accordingly to this approach, biased distributions in slopes and elevations are absent. To prevent discontinuities at the boundary between regions characterized by data with different resolution a cubic Hermite blending weight S-shaped function is adopted. The TIN of Italy consists of 1.39×109 triangles. The average triangle area ranges from 12 to about 13000 m2 accordingly to different morphologies and different sources. About 50% of the model has a local average triangle area <500 m2. The vertical accuracy of the obtained DEM is evaluated by more than 200000 sparse control points. The overall Root Mean Square Error (RMSE is less than 3.5 m. The obtained national-scale DEM constitutes an useful support to carry out accurate geomorphological and geological investigations over large areas. The problem of choosing the best step size in deriving a grid from a TIN is then discussed and a method to quantify the loss of vertical information is presented as a function of the grid step. Some examples of DEM application are outlined. Under request, an high resolution stereo image database of the whole Italian territory (derived from the presented DEM is available to browse via internet.

  15. Star Formation Histories of Dwarf Irregular Galaxies

    Science.gov (United States)

    Skillman, Evan

    1995-07-01

    We propose to obtain deep WFPC2 `BVI' color-magnitude diagrams {CMDs} for the dwarf irregular {dI} Local Group galaxies GR 8, Leo A, Pegasus, and Sextans A. In addition to resolved stars, we will use star clusters, and especially any globulars, to probe the history of intense star formation. These data will allow us to map the Pop I and Pop II stellar components, and thereby construct the first detailed star formation histories for non-interacting dI galaxies. Our results will bear on a variety of astrophysical problems, including the evolution of small galaxies, distances in the Local Group, age-metallicity distributions in small galaxies, ages of dIs, and the physics of star formation. The four target galaxies are typical dI systems in terms of luminosity, gas content, and H II region abundance, and represent a range in current star forming activity. They are sufficiently near to allow us to reach to stars at M_V = 0, have 0.1 of the luminosity of the SMC and 0.25 of its oxygen abundance. Unlike the SMC, these dIs are not near giant galaxies. This project will allow the extension of our knowledge of stellar populations in star forming galaxies from the spirals in the Local Group down to its smallest members. We plan to take maximum advantage of the unique data which this project will provide. Our investigator team brings extensive and varied experience in studies of dwarf galaxies, stellar populations, imaging photometry, and stellar evolution to this project.

  16. Stability of a Bose Condensate in the presence of regular and irregular potentials

    International Nuclear Information System (INIS)

    Gunn, J.M.F.

    1984-05-01

    The stability of an interacting Bose Condensate in the presence of a periodic potential is discussed. The condensate is destroyed if the potential is sufficiently strong, for certain densities of particles. Secondly irregular potentials of two types are considered: a dilute set of ''defect'' potentials in an otherwise periodic potential; and a highly irregular potential. In the first case, if the defect potential is sufficiently strong, the condensate is found to have a depletion which varies with the concentration of the defects. In the latter case it is argued that the condensate is totally destroyed. The consequences of the theory for experiments on 4 He films are discussed, and some new experiments proposed. (author)

  17. Very high latitude F-region irregularities observed by HF-radar backscatter

    International Nuclear Information System (INIS)

    Baker, K.B.; Greenwald, R.A.; Tsunoda, R.T.

    1983-01-01

    In February and March, 1982, a coherent scatter HF radar was operated from Cleary, Alaska to observe 7- to 15-m wavelength F-region plasma irregularities near the poleward edge of the auroral zone and in the polar cap. The radar operated for five days from February 25 to March 1 and produced approximately 700,000 Doppler spectra during that time. Of those nearly 700,000 spectra, approximately 10% showed backscattered power 3 dB or more above the noise level. A ray tracing technique using electron densities determined by the Chatanika incoherent scatter radar was used to predict locations where the HF waves were approximately normal to the magnetic field. If those locations were also to contain small scale electron density structure, then one would expect them to backscatter the HF waves. Several comparisons were made between predicted and observed locations of radiowave backscatter and excellent agreement was obtained. In addition, comparisons of the Doppler velocities observed by the coherent scatter HF radar and those observed by the Chatanika radar showed good agreement, suggesting that the plasma irregularities observed by the HF radar drift with the ambient plasma. In addition, average vector velocities calculated for the entire 5-day period show a flow pattern consistent with polar cap convection models. This again indicates that the irregularities drift with the plasma, as is predicted by a number of theories of F-region plasma irregularities. In the summer of 1983, the research program begun with those measurements will be continued with a steerable phased-array HF radar located at Goose Bay, Labrador, that will view the same ionospheric region as does the Sondre Stromfjord incoherent scatter radar

  18. Menarche delay and menstrual irregularities persist in adolescents with type 1 diabetes

    Directory of Open Access Journals (Sweden)

    McFann Kim

    2011-05-01

    Full Text Available Abstract Background Menarche delay has been reported in adolescent females with type 1 diabetes (T1DM, perhaps due to poor glycemic control. We sought to compare age at menarche between adolescent females with T1DM and national data, and to identify factors associated with delayed menarche and menstrual irregularity in T1DM. Methods This was a cross-sectional study and females ages 12- 24 years (n = 228 with at least one menstrual period were recruited during their outpatient diabetes clinic appointment. The National Health and Nutrition Examination Survey (NHANES 2001-2006 data (n = 3690 for females 12-24 years were used as a control group. Results Age at menarche was later in adolescent females with T1DM diagnosed prior to menarche (12.81 +/- 0.09 years (mean+/- SE (n = 185 than for adolescent females diagnosed after menarche (12.17 0.19 years, p = 0.0015 (n = 43. Average age of menarche in NHANES was 12.27 +/- 0.038 years, which was significantly earlier than adolescent females with T1DM prior to menarche (p p = 0.77. Older age at menarche was negatively correlated with BMI z-score (r = -0.23 p = 0.0029 but not hemoglobin A1c (A1c at menarche (r = 0.01, p = 0.91. Among 181 adolescent females who were at least 2 years post menarche, 63 (35% reported usually or always irregular cycles. Conclusion Adolescent females with T1DM had a later onset of menarche than both adolescent females who developed T1DM after menarche and NHANES data. Menarche age was negatively associated with BMI z-score, but not A1c. Despite improved treatment in recent decades, menarche delay and high prevalence of menstrual irregularity is still observed among adolescent females with T1DM.

  19. Traffic dispersion through a series of signals with irregular split

    Science.gov (United States)

    Nagatani, Takashi

    2016-01-01

    We study the traffic behavior of a group of vehicles moving through a sequence of signals with irregular splits on a roadway. We present the stochastic model of vehicular traffic controlled by signals. The dynamic behavior of vehicular traffic is clarified by analyzing traffic pattern and travel time numerically. The group of vehicles breaks up more and more by the irregularity of signal's split. The traffic dispersion is induced by the irregular split. We show that the traffic dispersion depends highly on the cycle time and the strength of split's irregularity. Also, we study the traffic behavior through the series of signals at the green-wave strategy. The dependence of the travel time on offset time is derived for various values of cycle time. The region map of the traffic dispersion is shown in (cycle time, offset time)-space.

  20. Irregular Warfare: Impact on Future Professional Military Education

    National Research Council Canada - National Science Library

    Paschal, David G

    2006-01-01

    ... to operate effectively in an irregular warfare environment. The utility of a decisive war between nation states continues to decline and will eventually reach critical mass based upon the extreme imbalance of military power and a U.S. monopoly...

  1. Irregular Warfare: Special Operations Joint Professional Military Education Transformation

    National Research Council Canada - National Science Library

    Cannady, Bryan H

    2008-01-01

    ... on today's battlefront in Afghanistan and Iraq and in the Global War on Terrorism (GWOT). At the forefront of the GWOT and irregular warfare are the United States Special Operations Command (USSOCOM...

  2. Drug Intoxicated Irregular Fighters: Complications, Dangers, and Responses

    National Research Council Canada - National Science Library

    Kan, Paul R

    2008-01-01

    .... Drug consumption in contemporary wars has coincided with the use of child soldiers, has led to increased unpredictability among irregular fighters, provided the conditions for the breakdown of social...

  3. Justice: A Problem for Military Ethics during Irregular War

    National Research Council Canada - National Science Library

    Bauer, John W

    2008-01-01

    ... is?" or "Justice according to whom?" The relative nature of the term "justice" creates a problem for military ethics, particularly when soldiers try to determine what actions are morally acceptable when they are engaged in irregular warfare...

  4. Irregular Warfare: New Challenges for Civil-Military Relations

    National Research Council Canada - National Science Library

    Cronin, Patrick M

    2008-01-01

    .... Irregular warfare introduces new complications to what Eliot Cohen has called an unequal dialogue between civilian and military leaders in which civilian leaders hold the true power but must modulate...

  5. Role of parametric decay instabilities in generating ionospheric irregularities

    International Nuclear Information System (INIS)

    Kuo, S.P.; Cheo, B.R.; Lee, M.C.

    1983-01-01

    We show that purely growing instabilities driven by the saturation spectrum of parametric decay instabilities can produce a broad spectrum of ionospheric irregularities. The threshold field Vertical BarE/sub th/Vertical Bar of the instabilities decreases with the scale lengths lambda of the ionospheric irregularities as Vertical BarE/sub th/Vertical Barproportionallambda -2 in the small-scale range ( -2 with scale lengths larger than a few kilometers. The excitation of kilometer-scale irregularities is strictly restricted by the instabilities themselves and by the spatial inhomogeneity of the medium. These results are drawn from the analyses of four-wave interaction. Ion-neutral collisions impose no net effect on the instabilities when the excited ionospheric irregularities have a field-aligned nature

  6. Edge irregular total labellings for graphs of linear size

    DEFF Research Database (Denmark)

    Brandt, Stephan; Rautenbach, D.; Miškuf, J.

    2009-01-01

    As an edge variant of the well-known irregularity strength of a graph G = (V, E) we investigate edge irregular total labellings, i.e. functions f : V ∪ E → {1, 2, ..., k} such that f (u) + f (u v) + f (v) ≠ f (u) + f (u v) + f (v) for every pair of different edges u v, u v ∈ E. The smallest possi...

  7. Ionospheric Irregularities at Mars Probed by MARSIS Topside Sounding

    Science.gov (United States)

    Harada, Y.; Gurnett, D. A.; Kopf, A. J.; Halekas, J. S.; Ruhunusiri, S.

    2018-01-01

    The upper ionosphere of Mars contains a variety of perturbations driven by solar wind forcing from above and upward propagating atmospheric waves from below. Here we explore the global distribution and variability of ionospheric irregularities around the exobase at Mars by analyzing topside sounding data from the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) instrument on board Mars Express. As irregular structure gives rise to off-vertical echoes with excess propagation time, the diffuseness of ionospheric echo traces can be used as a diagnostic tool for perturbed reflection surfaces. The observed properties of diffuse echoes above unmagnetized regions suggest that ionospheric irregularities with horizontal wavelengths of tens to hundreds of kilometers are particularly enhanced in the winter hemisphere and at high solar zenith angles. Given the known inverse dependence of neutral gravity wave amplitudes on the background atmospheric temperature, the ionospheric irregularities probed by MARSIS are most likely associated with plasma perturbations driven by atmospheric gravity waves. Though extreme events with unusually diffuse echoes are more frequently observed for high solar wind dynamic pressures during some time intervals, the vast majority of the diffuse echo events are unaffected by varying solar wind conditions, implying limited influence of solar wind forcing on the generation of ionospheric irregularities. Combination of remote and in situ measurements of ionospheric irregularities would offer the opportunity for a better understanding of the ionospheric dynamics at Mars.

  8. Being publicly diagnosed

    DEFF Research Database (Denmark)

    Konradsen, Hanne; Lillebaek, Troels; Wilcke, Torgny

    2014-01-01

    a patient with TB, and finally being in medical treatment. Before being diagnosed with TB, patients were weighing between biding their time and deciding to undergo an examination. Social pressure and feelings of social responsibility tended to affect the decision. Having undergone the examination......INTRODUCTION: Tuberculosis (TB) is a disease which affects people worldwide, but there is knowledge lacking about patients' experiences in low-prevalence and high-income countries. AIM: To provide a theoretical framework for the process of being diagnosed with tuberculosis in a Danish setting....... METHOD: A grounded theory design with field studies and qualitative interviews, following the recommendations from Glaser and Strauss. RESULT: A process of being publicly diagnosed was identified, which developed during the patient's trajectory from being on the way to becoming a patient, becoming...

  9. Deterministic Approach to Detect Heart Sound Irregularities

    Directory of Open Access Journals (Sweden)

    Richard Mengko

    2017-07-01

    Full Text Available A new method to detect heart sound that does not require machine learning is proposed. The heart sound is a time series event which is generated by the heart mechanical system. From the analysis of heart sound S-transform and the understanding of how heart works, it can be deducted that each heart sound component has unique properties in terms of timing, frequency, and amplitude. Based on these facts, a deterministic method can be designed to identify each heart sound components. The recorded heart sound then can be printed with each component correctly labeled. This greatly help the physician to diagnose the heart problem. The result shows that most known heart sounds were successfully detected. There are some murmur cases where the detection failed. This can be improved by adding more heuristics including setting some initial parameters such as noise threshold accurately, taking into account the recording equipment and also the environmental condition. It is expected that this method can be integrated into an electronic stethoscope biomedical system.

  10. Fatigue damage estimation using irregularity factor. First report, irregularity factor calculations for narrow and broadband random time histories

    Science.gov (United States)

    Susuki, I.

    1981-11-01

    The results of an analysis of the irregularity factors of stationary and Gaussian random processes which are generated by filtering the output of a pure or a band-limited white noise are presented. An ideal band pass filter, a trapezoidal filter, and a Butterworth type band pass filter were examined. It was found that the values of the irregularity factors were approximately equal among these filters if only the end-slopes were the same rates. As the band width of filters increases, irregularity factors increase monotonically and approach the respective constant values depending on the end-slopes. This implies that the noise characteristics relevant to the fatigue damage such as statistical aspects of the height of the rise and fall or the distribution of the peak values are not changed for a broad band random time history. It was also found that the effect of band limitation of input white noise on irregularity factors is negligibly small.

  11. Experimental and theoretical study of the onset of the growth of an irregular metal electrodeposit

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Graciela [Laboratoire de Physique de la Matiere Condensee, CNRS-Ecole Polytechnique, F91128 Palaiseau Cedex (France); Laboratorio de Sistemas Complejos, Departamento de Computacion, Facultad de Ciencias, Exactas y Naturales, Universidad de Buenos Aires, 1428 Buenos Aires (Argentina); Rosso, Michel; Chazalviel, Jean-Noel [Laboratoire de Physique de la Matiere Condensee, CNRS-Ecole Polytechnique, F91128 Palaiseau Cedex (France); Chassaing, Elisabeth [IRDEP, EDF R and D, 6 Quai Watier, 78401 Chatou (France)

    2007-11-20

    Electrodeposition of a metal can produce aggregates with very irregular morphologies, in particular dendrites. In order to better understand these phenomena, we studied the preliminary stage of copper growth from copper sulfate by in situ optical experiments and impedance spectroscopy. Experiments were performed in a thin layer cell put in a vertical position, with cathode on top. Using a vertical cell instead of a horizontal one tends to stabilize the electrochemical system. The concentration measured by optical absorption is in agreement with theoretical prediction at the onset of polarization. Close to the limiting current density, oscillations were observed in the cell voltage. Impedance spectra could be fitted either using a simple equivalent circuit at low current density, or more complex calculations at high current density. (author)

  12. Diagnosing plant problems

    Science.gov (United States)

    Cheryl A. Smith

    2008-01-01

    Diagnosing Christmas tree problems can be a challenge, requiring a basic knowledge of plant culture and physiology, the effect of environmental influences on plant health, and the ability to identify the possible causes of plant problems. Developing a solution or remedy to the problem depends on a proper diagnosis, a process that requires recognition of a problem and...

  13. Orbital and Collisional Evolution of the Irregular Satellites

    Science.gov (United States)

    Nesvorný, David; Alvarellos, Jose L. A.; Dones, Luke; Levison, Harold F.

    2003-07-01

    The irregular moons of the Jovian planets are a puzzling part of the solar system inventory. Unlike regular satellites, the irregular moons revolve around planets at large distances in tilted and eccentric orbits. Their origin, which is intimately linked with the origin of the planets themselves, is yet to be explained. Here we report a study of the orbital and collisional evolution of the irregular satellites from times after their formation to the present epoch. The purpose of this study is to find out the features of the observed irregular moons that can be attributed to this evolution and separate them from signatures of the formation process. We numerically integrated ~60,000 test satellite orbits to map orbital locations that are stable on long time intervals. We found that the orbits highly inclined to the ecliptic are unstable due to the effect of the Kozai resonance, which radially stretches them so that satellites either escape from the Hill sphere, collide with massive inner moons, or impact the parent planet. We also found that prograde satellite orbits with large semimajor axes are unstable due to the effect of the evection resonance, which locks the orbit's apocenter to the apparent motion of the Sun around the parent planet. In such a resonance, the effect of solar tides on a resonant moon accumulates at each apocenter passage of the moon, which causes a radially outward drift of its orbital apocenter; once close to the Hill sphere, the moon escapes. By contrast, retrograde moons with large orbital semimajor axes are long-lived. We have developed an analytic model of the distant satellite orbits and used it to explain the results of our numerical experiments. In particular, we analytically studied the effect of the Kozai resonance. We numerically integrated the orbits of the 50 irregular moons (known by 2002 August 16) for 108 yr. All orbits were stable on this time interval and did not show any macroscopic variations that would indicate

  14. Bottomside sinusoidal irregularities in the equatorial F region. II - Cross-correlation and spectral analysis

    Science.gov (United States)

    Cragin, B. L.; Hanson, W. B.; Mcclure, J. P.; Valladares, C. E.

    1985-01-01

    Equatorial bottomside sinusoidal (BSS) irregularities have been studied by applying techniques of cross-correlation and spectral analysis to the Atmosphere Explorer data set. The phase of the cross-correlations of the plasma number density is discussed and the two drift velocity components observed using the retarding potential analyzer and ion drift meter on the satellite are discussed. Morphology is addressed, presenting the geographical distributions of the occurrence of BSS events for the equinoxes and solstices. Physical processes including the ion Larmor flux, interhemispheric plasma flows, and variations in the lower F region Pedersen conductivity are invoked to explain the findings.

  15. Geostatistical regularization operators for geophysical inverse problems on irregular meshes

    Science.gov (United States)

    Jordi, C.; Doetsch, J.; Günther, T.; Schmelzbach, C.; Robertsson, J. OA

    2018-05-01

    Irregular meshes allow to include complicated subsurface structures into geophysical modelling and inverse problems. The non-uniqueness of these inverse problems requires appropriate regularization that can incorporate a priori information. However, defining regularization operators for irregular discretizations is not trivial. Different schemes for calculating smoothness operators on irregular meshes have been proposed. In contrast to classical regularization constraints that are only defined using the nearest neighbours of a cell, geostatistical operators include a larger neighbourhood around a particular cell. A correlation model defines the extent of the neighbourhood and allows to incorporate information about geological structures. We propose an approach to calculate geostatistical operators for inverse problems on irregular meshes by eigendecomposition of a covariance matrix that contains the a priori geological information. Using our approach, the calculation of the operator matrix becomes tractable for 3-D inverse problems on irregular meshes. We tested the performance of the geostatistical regularization operators and compared them against the results of anisotropic smoothing in inversions of 2-D surface synthetic electrical resistivity tomography (ERT) data as well as in the inversion of a realistic 3-D cross-well synthetic ERT scenario. The inversions of 2-D ERT and seismic traveltime field data with geostatistical regularization provide results that are in good accordance with the expected geology and thus facilitate their interpretation. In particular, for layered structures the geostatistical regularization provides geologically more plausible results compared to the anisotropic smoothness constraints.

  16. Total edge irregularity strength of (n,t)-kite graph

    Science.gov (United States)

    Winarsih, Tri; Indriati, Diari

    2018-04-01

    Let G(V, E) be a simple, connected, and undirected graph with vertex set V and edge set E. A total k-labeling is a map that carries vertices and edges of a graph G into a set of positive integer labels {1, 2, …, k}. An edge irregular total k-labeling λ :V(G)\\cup E(G)\\to \\{1,2,\\ldots,k\\} of a graph G is a labeling of vertices and edges of G in such a way that for any different edges e and f, weights wt(e) and wt(f) are distinct. The weight wt(e) of an edge e = xy is the sum of the labels of vertices x and y and the label of the edge e. The total edge irregularity strength of G, tes(G), is defined as the minimum k for which a graph G has an edge irregular total k-labeling. An (n, t)-kite graph consist of a cycle of length n with a t-edge path (the tail) attached to one vertex of a cycle. In this paper, we investigate the total edge irregularity strength of the (n, t)-kite graph, with n > 3 and t > 1. We obtain the total edge irregularity strength of the (n, t)-kite graph is tes((n, t)-kite) = \\lceil \\frac{n+t+2}{3}\\rceil .

  17. Malaria burden in irregular migrants returning to Sri Lanka from human smuggling operations in West Africa and implications for a country reaching malaria elimination.

    Science.gov (United States)

    Wickramage, K; Galappaththy, G N L

    2013-05-01

    The number of malaria cases among irregular migrants returning to Sri Lanka has not been investigated. In the first 6 months of 2012 we screened 287 irregular migrants returning from seven West African nations to Sri Lanka for malaria to ascertain the risk of infection during migration. Four men were diagnosed as having malaria: three with Plasmodium falciparum had travelled to Togo and one with P. vivax had travelled to Guinea. The risk of contracting malaria was 14 cases per 1000. Facilitating a safe return with selective screening for at-risk inbound migrants flows is desirable as Sri Lanka advances towards its goal of malaria elimination.

  18. Liability for Diagnosing Malingering.

    Science.gov (United States)

    Weiss, Kenneth J; Van Dell, Landon

    2017-09-01

    Malingering is a medical diagnosis, but not a psychiatric disorder. The label imputes that an evaluee has intentionally engaged in false behavior or statements. By diagnosing malingering, psychiatrists pass judgment on truthfulness. Evaluees taking exception to the label may claim that the professional has committed defamation of character (libel or slander) when the diagnosis is wrong and costs the claimant money or benefits. Clinicians may counter by claiming immunity or that the diagnosis was made in good faith. This problem has come into focus in military and veterans' contexts, where diagnoses become thresholds for benefits. Through historical and literary examples, case law, and military/veterans' claims of disability and entitlement, the authors examine the potency of the malingering label and the potential liability for professionals and institutions of making this diagnosis. © 2017 American Academy of Psychiatry and the Law.

  19. On the Automatic Parallelization of Sparse and Irregular Fortran Programs

    Directory of Open Access Journals (Sweden)

    Yuan Lin

    1999-01-01

    Full Text Available Automatic parallelization is usually believed to be less effective at exploiting implicit parallelism in sparse/irregular programs than in their dense/regular counterparts. However, not much is really known because there have been few research reports on this topic. In this work, we have studied the possibility of using an automatic parallelizing compiler to detect the parallelism in sparse/irregular programs. The study with a collection of sparse/irregular programs led us to some common loop patterns. Based on these patterns new techniques were derived that produced good speedups when manually applied to our benchmark codes. More importantly, these parallelization methods can be implemented in a parallelizing compiler and can be applied automatically.

  20. Measurement of Dynamic Friction Coefficient on the Irregular Free Surface

    International Nuclear Information System (INIS)

    Yeom, S. H.; Seo, K. S.; Lee, J. H.; Lee, K. H.

    2007-01-01

    A spent fuel storage cask must be estimated for a structural integrity when an earthquake occurs because it freely stands on ground surface without a restriction condition. Usually the integrity estimation for a seismic load is performed by a FEM analysis, the friction coefficient for a standing surface is an important parameter in seismic analysis when a sliding happens. When a storage cask is placed on an irregular ground surface, measuring a friction coefficient of an irregular surface is very difficult because the friction coefficient is affected by the surface condition. In this research, dynamic friction coefficients on the irregular surfaces between a concrete cylinder block and a flat concrete slab are measured with two methods by one direction actuator

  1. NEOWISE: OBSERVATIONS OF THE IRREGULAR SATELLITES OF JUPITER AND SATURN

    Energy Technology Data Exchange (ETDEWEB)

    Grav, T. [Planetary Science Institute, Tucson, AZ 85719 (United States); Bauer, J. M.; Mainzer, A. K.; Masiero, J. R.; Sonnett, S.; Kramer, E. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Nugent, C. R.; Cutri, R. M., E-mail: tgrav@psi.edu [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States)

    2015-08-10

    We present thermal model fits for 11 Jovian and 3 Saturnian irregular satellites based on measurements from the WISE/NEOWISE data set. Our fits confirm spacecraft-measured diameters for the objects with in situ observations (Himalia and Phoebe) and provide diameters and albedo for 12 previously unmeasured objects, 10 Jovian and 2 Saturnian irregular satellites. The best-fit thermal model beaming parameters are comparable to what is observed for other small bodies in the outer solar system, while the visible, W1, and W2 albedos trace the taxonomic classifications previously established in the literature. Reflectance properties for the irregular satellites measured are similar to the Jovian Trojan and Hilda Populations, implying common origins.

  2. Irregular flowering patterns in terrestrial orchids: theories vs. empirical data

    Directory of Open Access Journals (Sweden)

    P. Kindlmann

    2001-11-01

    Full Text Available Empirical data on many species of terrestrial orchids suggest that their between-year flowering pattern is extremely irregular and unpredictable. A long search for the reason has hitherto proved inconclusive. Here we summarise and critically review the hypotheses that were put forward as explanations of this phenomenon: irregular flowering was attributed to costs associated with sexual reproduction, to herbivory, or to the chaotic behaviour of the system represented by difference equations describing growth of the vegetative and reproductive organs. None of these seems to explain fully the events of a transition from flowering one year to sterility or absence the next year. Data on the seasonal growth of leaves and inflorescence of two terrestrial orchid species, Epipactis albensis and Dactylorhiza fuchsii and our previous results are then used here to fill gaps in what has been published until now and to test alternative explanations of the irregular flowering patterns of orchids.

  3. Track Irregularity Time Series Analysis and Trend Forecasting

    Directory of Open Access Journals (Sweden)

    Jia Chaolong

    2012-01-01

    Full Text Available The combination of linear and nonlinear methods is widely used in the prediction of time series data. This paper analyzes track irregularity time series data by using gray incidence degree models and methods of data transformation, trying to find the connotative relationship between the time series data. In this paper, GM (1,1 is based on first-order, single variable linear differential equations; after an adaptive improvement and error correction, it is used to predict the long-term changing trend of track irregularity at a fixed measuring point; the stochastic linear AR, Kalman filtering model, and artificial neural network model are applied to predict the short-term changing trend of track irregularity at unit section. Both long-term and short-term changes prove that the model is effective and can achieve the expected accuracy.

  4. Exploring Manycore Multinode Systems for Irregular Applications with FPGA Prototyping

    Energy Technology Data Exchange (ETDEWEB)

    Ceriani, Marco; Palermo, Gianluca; Secchi, Simone; Tumeo, Antonino; Villa, Oreste

    2013-04-29

    We present a prototype of a multi-core architecture implemented on FPGA, designed to enable efficient execution of irregular applications on distributed shared memory machines, while maintaining high performance on regular workloads. The architecture is composed of off-the-shelf soft-core cores, local interconnection and memory interface, integrated with custom components that optimize it for irregular applications. It relies on three key elements: a global address space, multithreading, and fine-grained synchronization. Global addresses are scrambled to reduce the formation of network hot-spots, while the latency of the transactions is covered by integrating an hardware scheduler within the custom load/store buffers to take advantage from the availability of multiple executions threads, increasing the efficiency in a transparent way to the application. We evaluated a dual node system irregular kernels showing scalability in the number of cores and threads.

  5. Criticality predicts maximum irregularity in recurrent networks of excitatory nodes.

    Directory of Open Access Journals (Sweden)

    Yahya Karimipanah

    Full Text Available A rigorous understanding of brain dynamics and function requires a conceptual bridge between multiple levels of organization, including neural spiking and network-level population activity. Mounting evidence suggests that neural networks of cerebral cortex operate at a critical regime, which is defined as a transition point between two phases of short lasting and chaotic activity. However, despite the fact that criticality brings about certain functional advantages for information processing, its supporting evidence is still far from conclusive, as it has been mostly based on power law scaling of size and durations of cascades of activity. Moreover, to what degree such hypothesis could explain some fundamental features of neural activity is still largely unknown. One of the most prevalent features of cortical activity in vivo is known to be spike irregularity of spike trains, which is measured in terms of the coefficient of variation (CV larger than one. Here, using a minimal computational model of excitatory nodes, we show that irregular spiking (CV > 1 naturally emerges in a recurrent network operating at criticality. More importantly, we show that even at the presence of other sources of spike irregularity, being at criticality maximizes the mean coefficient of variation of neurons, thereby maximizing their spike irregularity. Furthermore, we also show that such a maximized irregularity results in maximum correlation between neuronal firing rates and their corresponding spike irregularity (measured in terms of CV. On the one hand, using a model in the universality class of directed percolation, we propose new hallmarks of criticality at single-unit level, which could be applicable to any network of excitable nodes. On the other hand, given the controversy of the neural criticality hypothesis, we discuss the limitation of this approach to neural systems and to what degree they support the criticality hypothesis in real neural networks. Finally

  6. Irregular Shaped Building Design Optimization with Building Information Modelling

    Directory of Open Access Journals (Sweden)

    Lee Xia Sheng

    2016-01-01

    Full Text Available This research is to recognise the function of Building Information Modelling (BIM in design optimization for irregular shaped buildings. The study focuses on a conceptual irregular shaped “twisted” building design similar to some existing sculpture-like architectures. Form and function are the two most important aspects of new buildings, which are becoming more sophisticated as parts of equally sophisticated “systems” that we are living in. Nowadays, it is common to have irregular shaped or sculpture-like buildings which are very different when compared to regular buildings. Construction industry stakeholders are facing stiff challenges in many aspects such as buildability, cost effectiveness, delivery time and facility management when dealing with irregular shaped building projects. Building Information Modelling (BIM is being utilized to enable architects, engineers and constructors to gain improved visualization for irregular shaped buildings; this has a purpose of identifying critical issues before initiating physical construction work. In this study, three variations of design options differing in rotating angle: 30 degrees, 60 degrees and 90 degrees are created to conduct quantifiable comparisons. Discussions are focused on three major aspects including structural planning, usable building space, and structural constructability. This research concludes that Building Information Modelling is instrumental in facilitating design optimization for irregular shaped building. In the process of comparing different design variations, instead of just giving “yes or no” type of response, stakeholders can now easily visualize, evaluate and decide to achieve the right balance based on their own criteria. Therefore, construction project stakeholders are empowered with superior evaluation and decision making capability.

  7. Low frequency sound reproduction in irregular rooms using CABS (Control Acoustic Bass System)

    DEFF Research Database (Denmark)

    Celestinos, Adrian; Nielsen, Sofus Birkedal

    2011-01-01

    of an irregular room model using the FDTD (Finite Difference Time Domain) method has been presented. CABS has been simulated in the irregular room model. Measurements of CABS in a real irregular room have been performed. The performance of CABS was affected by the irregular shape of the room due to the corner...

  8. Characterizing spontaneous irregular behavior in coupled map lattices

    International Nuclear Information System (INIS)

    Dobyns, York; Atmanspacher, Harald

    2005-01-01

    Two-dimensional coupled map lattices display, in a specific parameter range, a stable phase (quasi-) periodic in both space and time. With small changes to the model parameters, this stable phase develops spontaneous eruptions of non-periodic behavior. Although this behavior itself appears irregular, it can be characterized in a systematic fashion. In particular, parameter-independent features of the spontaneous eruptions may allow useful empirical characterizations of other phenomena that are intrinsically hard to predict and reproduce. Specific features of the distributions of lifetimes and emergence rates of irregular states display such parameter-independent properties

  9. Characterizing spontaneous irregular behavior in coupled map lattices

    Energy Technology Data Exchange (ETDEWEB)

    Dobyns, York [PEAR, Princeton University Princeton, NJ 08544-5263 (United States); Atmanspacher, Harald [Institut fuer Grenzgebiete der Psychologie und Psychohygiene Wilhelmstrasse 3a, Freiburg 79098 (Germany)]. E-mail: haa@igpp.de

    2005-04-01

    Two-dimensional coupled map lattices display, in a specific parameter range, a stable phase (quasi-) periodic in both space and time. With small changes to the model parameters, this stable phase develops spontaneous eruptions of non-periodic behavior. Although this behavior itself appears irregular, it can be characterized in a systematic fashion. In particular, parameter-independent features of the spontaneous eruptions may allow useful empirical characterizations of other phenomena that are intrinsically hard to predict and reproduce. Specific features of the distributions of lifetimes and emergence rates of irregular states display such parameter-independent properties.

  10. [Artificial cycle therapy of acupuncture and moxibustion for irregular menstruation].

    Science.gov (United States)

    Wu, Jie; Yang, Lijie; Chen, Yajie; Li, Qing; Chen, Lin

    2015-03-01

    Through the discussion on TCM physiological characters of females in follicular, ovulatory, luteal and menstrual phases and treatment principles, the clinical application of artificial cycle therapy of acupuncture and moxibustion was introduced for irregular menstruation and the typical cases were attached. It is suggested that the menstrual cycle follows the growth-consumption rule of yin, yang, qi and blood. The corresponding treatment principles should be applied in accordance with the change rule of menstrual cycle. Hence, it is worth to adopt the artificial cycle therapy of acupuncture and moxibustion for irregular menstruation in clinical application.

  11. Uniform irradiation of irregularly shaped cavities for photodynamic therapy.

    Science.gov (United States)

    Rem, A I; van Gemert, M J; van der Meulen, F W; Gijsbers, G H; Beek, J F

    1997-03-01

    It is difficult to achieve a uniform light distribution in irregularly shaped cavities. We have conducted a study on the use of hollow 'integrating' moulds for more uniform light delivery of photodynamic therapy in irregularly shaped cavities such as the oral cavity. Simple geometries such as a cubical box, a sphere, a cylinder and a 'bottle-neck' geometry have been investigated experimentally and the results have been compared with computed light distributions obtained using the 'radiosity method'. A high reflection coefficient of the mould and the best uniform direct irradiance possible on the inside of the mould were found to be important determinants for achieving a uniform light distribution.

  12. ARCAD3-SAFARI coordinated study of auroral and polar F-region ionospheric irregularities

    International Nuclear Information System (INIS)

    Villain, J.P.; Hanuise, C.

    1986-01-01

    Simultaneous observations of F-region ionospheric irregularities have been performed with the SAFARI ground-based HF radars and the ISOPROBE experiment on board the AUREOL-3 satellite. Among seven orbits during which the satellite trajectory was directly in the radar beam or in the vicinity, four of them have been analyzed in detail. The spectral power of the electron density variations ΔNsub(e)/Nsub(e) has been calculated for wavelengths between 20 m and 1 km from the isoprobe high time resolution thermal plasma measurements. One spectrum is obtained every 1.2 s, a time which corresponds to about 10 km along the satellite trajectory. The presence of echoes observed in the F-region with the SAFARI radars is compared with the spectral power of the electron density variations deduced from the ISOPROBE ''in situ'' measurements. A good agreement is found between the two sets of observations and a numerical value of the spectral power corresponding to detection of echoes by the radar is given. A synoptical view of the event is given and interpreted according to the existing theories of plasma irregularities

  13. Reconstruction in PET cameras with irregular sampling and depth of interaction capability

    International Nuclear Information System (INIS)

    Virador, P.R.G.; Moses, W.W.; Huesman, R.H.

    1998-01-01

    The authors present 2D reconstruction algorithms for a rectangular PET camera capable of measuring depth of interaction (DOI). The camera geometry leads to irregular radial and angular sampling of the tomographic data. DOI information increases sampling density, allowing the use of evenly spaced quarter-crystal width radial bins with minimal interpolation of irregularly spaced data. In the regions where DOI does not increase sampling density (chords normal to crystal faces), fine radial sinogram binning leads to zero efficiency bins if uniform angular binning is used. These zero efficiency sinogram bins lead to streak artifacts if not corrected. To minimize these unnormalizable sinogram bins the authors use two angular binning schemes: Fixed Width and Natural Width. Fixed Width uses a fixed angular width except in the problem regions where appropriately chosen widths are applied. Natural Width uses angle widths which are derived from intrinsic detector sampling. Using a modified filtered-backprojection algorithm to accommodate these angular binning schemes, the authors reconstruct artifact free images with nearly isotropic and position independent spatial resolution. Results from Monte Carlo data indicate that they have nearly eliminated image degradation due to crystal penetration

  14. Two media method for linear attenuation coefficient determination of irregular soil samples; Metodo dos dois meios para a determinacao do coeficiente de atenuacao linear de amostras irregulares de solos

    Energy Technology Data Exchange (ETDEWEB)

    Vici, Carlos Henrique Georges

    2004-07-01

    In several situations of nuclear applications, the knowledge of gamma-ray linear attenuation coefficient for irregular samples is necessary, such as in soil physics and geology. This work presents the validation of a methodology for the determination of the linear attenuation coefficient ({mu}) of irregular shape samples, in such a way that it is not necessary to know the thickness of the considered sample. With this methodology irregular soil samples (undeformed field samples) from Londrina region, north of Parana were studied. It was employed the two media method for the {mu} determination. It consists of the {mu} determination through the measurement of a gamma-ray beam attenuation by the sample sequentially immersed in two different media, with known and appropriately chosen attenuation coefficients. For comparison, the theoretical value of {mu} was calculated by the product of the mass attenuation coefficient, obtained by the WinXcom code, and the measured value of the density sample. This software employs the chemical composition of the samples and supplies a table of the mass attenuation coefficients versus the photon energy. To verify the validity of the two media method, compared with the simple gamma ray transmission method, regular pome stone samples were used. With these results for the attenuation coefficients and their respective deviations, it was possible to compare the two methods. In this way we concluded that the two media method is a good tool for the determination of the linear attenuation coefficient of irregular materials, particularly in the study of soils samples. (author)

  15. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed with Cancer Fertility Preservation for Children Diagnosed ... for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed with Cancer Fertility Preservation for Children Diagnosed ...

  16. Diagnoser som styringshybrider

    DEFF Research Database (Denmark)

    Bossen, Claus; Danholt, Peter; Ubbesen, Morten Bonde

    2016-01-01

    - Relaterede Grupper (DRG). DRG er et internationalt udbredt system til at knytte patienter og deres behandlingsomkostninger sammen i faste kategorier med henblik på at måle hospitalers produktivitet. Med afsæt i Science-Technology-Studies (STS)-feltet analyserer artiklen, hvorledes diagnoser overskrider deres......, hvordan DRG-systemet alternativt kan anskues som en samfundsudviklende infrastruktur, idet det forsamler og skaber gensidigt involverende interaktioner imellem politiske, administrative og sundhedsprofessionelle domæner. En sådan indsigt bidrager til en udvidet forståelse af infrastrukturers roller som...

  17. Runtime buffer management to improve the performance in irregular ...

    Indian Academy of Sciences (India)

    S¯adhan¯a Vol. 40, Part 4, June 2015, pp. 1117–1137. c Indian Academy of Sciences. Runtime buffer management to improve the performance in irregular Network-on-Chip architecture. UMAMAHESWARI S1,∗, MEGANATHAN D2 and. RAJA PAUL PERINBAM J3. 1Department of Information Technology, Anna University, ...

  18. Structure Irregularity Impedes Drop Roll-Off at Superhydrophobic Surfaces

    DEFF Research Database (Denmark)

    Larsen, Simon Tylsgaard; Andersen, Nis Korsgaard; Søgaard, Emil

    2014-01-01

    -off angles is found to be caused by a decrease of the receding contact angle, which in turn is caused by an increase of the triple phase contact line of the drops for those more irregular surfaces. To understand the observation, we propose to treat the microdrops as rigid bodies and apply a torque balance...

  19. The regularized monotonicity method: detecting irregular indefinite inclusions

    DEFF Research Database (Denmark)

    Garde, Henrik; Staboulis, Stratos

    2018-01-01

    inclusions, where the conductivity distribution has both more and less conductive parts relative to the background conductivity; one such method is the monotonicity method of Harrach, Seo, and Ullrich. We formulate the method for irregular indefinite inclusions, meaning that we make no regularity assumptions...

  20. Size and Albedo of Irregular Saturnian Satellites from Spitzer Observations

    NARCIS (Netherlands)

    Mueller, Michael; Grav, T.; Trilling, D.; Stansberry, J.; Sykes, M.

    2008-01-01

    Using MIPS onboard the Spitzer Space Telescope, we observed the thermal emission (24 and, for some targets, 70 um) of eight irregular satellites of Saturn: Albiorix, Siarnaq, Paaliaq, Kiviuq, Ijiraq, Tarvos, Erriapus, and Ymir. We determined the size and albedo of all targets. An analysis of

  1. Interagency Cooperation for Irregular Warfare at the Combatant Command

    Science.gov (United States)

    2009-01-01

    enemy’s command capability.16 Salamoni argued that the term “irregular warfare” belies an ethnocentric perspective of conflict that will limit military...duty military staffing to form the nucleus of the organization, which would receive augmentation from additional assigned reservists and interagency

  2. Convection-diffusion lattice Boltzmann scheme for irregular lattices

    NARCIS (Netherlands)

    Sman, van der R.G.M.; Ernst, M.H.

    2000-01-01

    In this paper, a lattice Boltzmann (LB) scheme for convection diffusion on irregular lattices is presented, which is free of any interpolation or coarse graining step. The scheme is derived using the axioma that the velocity moments of the equilibrium distribution equal those of the

  3. Swiveling Lathe Jaw Concept for Holding Irregular Pieces

    Science.gov (United States)

    David, J.

    1966-01-01

    Clamp holds irregularly shaped pieces in lathe chuck without damage and eliminates excessive time in selecting optimum mounting. Interchangeable jaws ride in standard jaw slots but swivel so that the jaw face bears evenly against the workpiece regardless of contour. The jaws can be used on both engine and turret lathes.

  4. Why type 2 supernovae do not explode in irregular galaxies

    International Nuclear Information System (INIS)

    Shklovskij, I.S.

    1984-01-01

    The conclusion is drawn that reason for an absence of type 2 supernovae explosions in irregular galaxies is their peculiar chemical composition. The observed lack of stellar wind from massive hot giants is due to relatively low heavy element abundance. For this reason evolving massive stars do not form an extended dense envelopes that is a necessary condition for the type 2 supernova phenomenon

  5. First stellar abundances in the dwarf irregular galaxy Sextans A

    NARCIS (Netherlands)

    Kaufer, A; Venn, KA; Tolstoy, E; Pinte, C; Kudritzki, RP

    We present the abundance analyses of three isolated A-type supergiant stars in the dwarf irregular galaxy Sextans A (= DDO 75) from high-resolution spectra obtained with the Ultraviolet-Visual Echelle Spectrograph (UVES) on the Kueyen telescope (UT2) of the ESO Very Large Telescope (VLT). Detailed

  6. Spectral element method for wave propagation on irregular domains

    Indian Academy of Sciences (India)

    Yan Hui Geng

    2018-03-14

    Mar 14, 2018 ... Abstract. A spectral element approximation of acoustic propagation problems combined with a new mapping method on irregular domains is proposed. Following this method, the Gauss–Lobatto–Chebyshev nodes in the standard space are applied to the spectral element method (SEM). The nodes in the ...

  7. On the Total Edge Irregularity Strength of Generalized Butterfly Graph

    Science.gov (United States)

    Dwi Wahyuna, Hafidhyah; Indriati, Diari

    2018-04-01

    Let G(V, E) be a connected, simple, and undirected graph with vertex set V and edge set E. A total k-labeling is a map that carries vertices and edges of a graph G into a set of positive integer labels {1, 2, …, k}. An edge irregular total k-labeling λ: V(G) ∪ E(G) → {1, 2, …, k} of a graph G is a total k-labeling such that the weights calculated for all edges are distinct. The weight of an edge uv in G, denoted by wt(uv), is defined as the sum of the label of u, the label of v, and the label of uv. The total edge irregularity strength of G, denoted by tes(G), is the minimum value of the largest label k over all such edge irregular total k-labelings. A generalized butterfly graph, BFn , obtained by inserting vertices to every wing with assumption that sum of inserting vertices to every wing are same then it has 2n + 1 vertices and 4n ‑ 2 edges. In this paper, we investigate the total edge irregularity strength of generalized butterfly graph, BFn , for n > 2. The result is tes(B{F}n)=\\lceil \\frac{4n}{3}\\rceil .

  8. On a new process for cusp irregularity production

    Directory of Open Access Journals (Sweden)

    H. C. Carlson

    2008-09-01

    Full Text Available Two plasma instability mechanisms were thought until 2007 to dominate the formation of plasma irregularities in the F region high latitude and polar ionosphere; the gradient-drift driven instability, and the velocity-shear driven instability. The former mechanism was accepted as accounting for plasma structuring in polar cap patches, the latter for plasma structuring in polar cap sun aligned arcs. Recent work has established the need to replace this view of the past two decades with a new patch plasma structuring process (not a new mechanism, whereby shear-driven instabilities first rapidly structure the entering plasma, after which gradient drift instabilities build on these large "seed" irregularities. Correct modeling of cusp and early polar cap patch structuring will not be accomplished without allowing for this compound process. This compound process explains several previously unexplained characteristics of cusp and early polar cap patch irregularities. Here we introduce additional data, coincident in time and space, to extend that work to smaller irregularity scale sizes and relate it to the structured cusp current system.

  9. Irregular ionization and scintillation of the ionosphere in equator region

    International Nuclear Information System (INIS)

    Shinno, Kenji

    1974-01-01

    The latest studies on the scintillation in satellite communication and its related irregularities of ionosphere are reviewed. They were made clear by means of spread-F, the direct measurement with scientific satellites, VHF radar observation, and radio wave propagation in equator region. The fundamental occurrence mechanism may be instability of plasma caused by the interaction of movement of neutral atmosphere and magnetic field. Comparison of the main characteristics of scintillation, namely the dependence on region, solar activity, season, local time, geomagnetic activity, movement in ionosphere, scattering source, frequency and transmission mode, was made and the correlation among spread-F, TEP and scintillation was summarized. The latest principal studies were the observations made by Intelsat and by ATS. Scintillation of Syncom-3 and Intelsat-II-F2 and spread-F by ionosphere observation were compared by Huang. It is reasonable to consider that the occurrence of scintillation is caused by the irregularities in ionosphere which are particular in equator region, because of the similar characteristics of spread-F and VHF propagation in the equator region. These three phenomena may occur in relation to the irregularities of ionosphere. Interpretation of spread-F and the abnormal propagation wave across the equator are given. The study using VHF radar and the movement of irregular ionization by the direct observation with artificial satellites are reviewd. (Iwakiri, K.)

  10. Third-order theory for multi-directional irregular waves

    DEFF Research Database (Denmark)

    Madsen, Per A.; Fuhrman, David R.

    2012-01-01

    A new third-order solution for multi-directional irregular water waves in finite water depth is presented. The solution includes explicit expressions for the surface elevation, the amplitude dispersion and the vertical variation of the velocity potential. Expressions for the velocity potential at...

  11. Irregular menses: an independent risk factor for gestational diabetes mellitus.

    Science.gov (United States)

    Haver, Mary Claire; Locksmith, Gregory J; Emmet, Emily

    2003-05-01

    Our purpose was to determine whether a history of irregular menses predicts gestational diabetes mellitus independently of traditional risk factors. We analyzed demographic characteristics, body mass index, and menstrual history of 85 pregnant women with gestational diabetes mellitus and compared them with 85 systematically selected control subjects who were matched for age, race, and delivery year. Subjects with pregestational diabetes mellitus, previous gestational diabetes mellitus, family history of diabetes mellitus, weight >200 pounds, previous macrosomic infants, or previous stillbirth were excluded. Demographic characteristics between case and control groups were similar. Mean body mass index was higher among cases (26.5 kg/m(2)) versus control subjects (24.5 kg/m(2), P =.004). Irregular cycles were more prevalent in the cases (24% vs 7%, P =.006). With the use of body mass index as a stratification factor, menstrual irregularity maintained a strong association with gestational diabetes mellitus (P =.014). A history of irregular menstrual cycles was a significant independent predictor of gestational diabetes mellitus. If selective screening is implemented for gestational diabetes mellitus, such history should be considered in the decision of whom to test.

  12. Spectral element method for wave propagation on irregular domains

    Indian Academy of Sciences (India)

    A spectral element approximation of acoustic propagation problems combined with a new mapping method on irregular domains is proposed. Following this method, the Gauss–Lobatto–Chebyshev nodes in the standard space are applied to the spectral element method (SEM). The nodes in the physical space are ...

  13. New advantages of the combined GPS and GLONASS observations for high-latitude ionospheric irregularities monitoring: case study of June 2015 geomagnetic storm

    Science.gov (United States)

    Cherniak, Iurii; Zakharenkova, Irina

    2017-05-01

    Monitoring, tracking and nowcasting of the ionospheric plasma density disturbances using dual-frequency measurements of the Global Positioning System (GPS) signals are effectively carried out during several decades. Recent rapid growth and modernization of the ground-based segment gives an opportunity to establish a great database consisting of more than 6000 stations worldwide which provide GPS signals measurements with an open access. Apart of the GPS signals, at least two-third of these stations receive simultaneously signals transmitted by another Global Navigation Satellite System (GNSS)—the Russian system GLONASS. Today, GLONASS signal measurements are mainly used in navigation and geodesy only and very rarely for ionosphere research. We present the first results demonstrating advantages of using several independent but compatible GNSS systems like GPS and GLONASS for improvement of the permanent monitoring of the high-latitude ionospheric irregularities. For the first time, the high-resolution two-dimensional maps of ROTI perturbation were made using not only GPS but also GLONASS measurements. We extend the use of the ROTI maps for analyzing ionospheric irregularities distribution. We demonstrate that the meridional slices of the ROTI maps can be effectively used to study the occurrence and temporal evolution of the ionospheric irregularities. The meridional slices of the geographical sectors with a high density of the GPS and GLONASS measurements can represent spatio-temporal dynamics of the intense ionospheric plasma density irregularities with very high resolution, and they can be effectively used for detailed study of the space weather drivers on the processes of the ionospheric irregularities generation, development and their lifetimes. Using a representative database of 5800 ground-based GNSS stations located worldwide, we have investigated the occurrence of the high-latitude ionospheric plasma density irregularities during the geomagnetic storm of

  14. Classical limit of irregular blocks and Mathieu functions

    International Nuclear Information System (INIS)

    Piątek, Marcin; Pietrykowski, Artur R.

    2016-01-01

    The Nekrasov-Shatashvili limit of the N = 2 SU(2) pure gauge (Ω-deformed) super Yang-Mills theory encodes the information about the spectrum of the Mathieu operator. On the other hand, the Mathieu equation emerges entirely within the frame of two-dimensional conformal field theory (2d CFT) as the classical limit of the null vector decoupling equation for some degenerate irregular block. Therefore, it seems to be possible to investigate the spectrum of the Mathieu operator employing the techniques of 2d CFT. To exploit this strategy, a full correspondence between the Mathieu equation and its realization within 2d CFT has to be established. In our previous paper http://dx.doi.org/10.1007/JHEP12(2014)032, we have found that the expression of the Mathieu eigenvalue given in terms of the classical irregular block exactly coincides with the well known weak coupling expansion of this eigenvalue in the case in which the auxiliary parameter is the noninteger Floquet exponent. In the present work we verify that the formula for the corresponding eigenfunction obtained from the irregular block reproduces the so-called Mathieu exponent from which the noninteger order elliptic cosine and sine functions may be constructed. The derivation of the Mathieu equation within the formalism of 2d CFT is based on conjectures concerning the asymptotic behaviour of irregular blocks in the classical limit. A proof of these hypotheses is sketched. Finally, we speculate on how it could be possible to use the methods of 2d CFT in order to get from the irregular block the eigenvalues of the Mathieu operator in other regions of the coupling constant.

  15. Comparison of correlation analysis techniques for irregularly sampled time series

    Directory of Open Access Journals (Sweden)

    K. Rehfeld

    2011-06-01

    Full Text Available Geoscientific measurements often provide time series with irregular time sampling, requiring either data reconstruction (interpolation or sophisticated methods to handle irregular sampling. We compare the linear interpolation technique and different approaches for analyzing the correlation functions and persistence of irregularly sampled time series, as Lomb-Scargle Fourier transformation and kernel-based methods. In a thorough benchmark test we investigate the performance of these techniques.

    All methods have comparable root mean square errors (RMSEs for low skewness of the inter-observation time distribution. For high skewness, very irregular data, interpolation bias and RMSE increase strongly. We find a 40 % lower RMSE for the lag-1 autocorrelation function (ACF for the Gaussian kernel method vs. the linear interpolation scheme,in the analysis of highly irregular time series. For the cross correlation function (CCF the RMSE is then lower by 60 %. The application of the Lomb-Scargle technique gave results comparable to the kernel methods for the univariate, but poorer results in the bivariate case. Especially the high-frequency components of the signal, where classical methods show a strong bias in ACF and CCF magnitude, are preserved when using the kernel methods.

    We illustrate the performances of interpolation vs. Gaussian kernel method by applying both to paleo-data from four locations, reflecting late Holocene Asian monsoon variability as derived from speleothem δ18O measurements. Cross correlation results are similar for both methods, which we attribute to the long time scales of the common variability. The persistence time (memory is strongly overestimated when using the standard, interpolation-based, approach. Hence, the Gaussian kernel is a reliable and more robust estimator with significant advantages compared to other techniques and suitable for large scale application to paleo-data.

  16. Diagnosing night sweats.

    Science.gov (United States)

    Viera, Anthon J; Bond, Michael M; Yates, Scott W

    2003-03-01

    Night sweats are a common outpatient complaint, yet literature on the subject is scarce. Tuberculosis and lymphoma are diseases in which night sweats are a dominant symptom, but these are infrequently found to be the cause of night sweats in modern practice. While these diseases remain important diagnostic considerations in patients with night sweats, other diagnoses to consider include human immunodeficiency virus, gastroesophageal reflux disease, obstructive sleep apnea, hyperthyroidism, hypoglycemia, and several less common diseases. Antihypertensives, antipyretics, other medications, and drugs of abuse such as alcohol and heroin may cause night sweats. Serious causes of night sweats can be excluded with a thorough history, physical examination, and directed laboratory and radiographic studies. If a history and physical do not reveal a possible diagnosis, physicians should consider a purified protein derivative, complete blood count, human immunodeficiency virus test, thyroid-stimulating hormone test, erythrocyte sedimentation rate evaluation, chest radiograph, and possibly chest and abdominal computed tomographic scans and bone marrow biopsy.

  17. Diagnosable structured logic array

    Science.gov (United States)

    Whitaker, Sterling (Inventor); Miles, Lowell (Inventor); Gambles, Jody (Inventor); Maki, Gary K. (Inventor)

    2009-01-01

    A diagnosable structured logic array and associated process is provided. A base cell structure is provided comprising a logic unit comprising a plurality of input nodes, a plurality of selection nodes, and an output node, a plurality of switches coupled to the selection nodes, where the switches comprises a plurality of input lines, a selection line and an output line, a memory cell coupled to the output node, and a test address bus and a program control bus coupled to the plurality of input lines and the selection line of the plurality of switches. A state on each of the plurality of input nodes is verifiably loaded and read from the memory cell. A trusted memory block is provided. The associated process is provided for testing and verifying a plurality of truth table inputs of the logic unit.

  18. Imaging irregular magma reservoirs with InSAR and GPS observations: Application to Kilauea and Copahue volcanoes

    Science.gov (United States)

    Lundgren, P.; Camacho, A.; Poland, M. P.; Miklius, A.; Samsonov, S. V.; Milillo, P.

    2013-12-01

    The availability of synthetic aperture radar (SAR) interferometry (InSAR) data has increased our awareness of the complexity of volcano deformation sources. InSAR's spatial completeness helps identify or clarify source process mechanisms at volcanoes (i.e. Mt. Etna east flank motion; Lazufre crustal magma body; Kilauea dike complexity) and also improves potential model realism. In recent years, Bayesian inference methods have gained widespread use because of their ability to constrain not only source model parameters, but also their uncertainties. They are computationally intensive, however, which tends to limit them to a few geometrically rather simple source representations (for example, spheres). An alternative approach involves solving for irregular pressure and/or density sources from a three-dimensional (3-D) grid of source/density cells. This method has the ability to solve for arbitrarily shaped bodies of constant absolute pressure/density difference. We compare results for both Bayesian (a Markov chain Monte Carlo algorithm) and the irregular source methods for two volcanoes: Kilauea, Hawaii, and Copahue, Argentina-Chile border. Kilauea has extensive InSAR and GPS databases from which to explore the results for the irregular method with respect to the Bayesian approach, prior models, and an extensive set of ancillary data. One caveat, however, is the current restriction in the irregular model inversion to volume-pressure sources (and at a single excess pressure change), which limits its application in cases where sources such as faults or dikes are present. Preliminary results for Kilauea summit deflation during the March 2011 Kamoamoa eruption suggests a northeast-elongated magma body lying roughly 1-1.5 km below the surface. Copahue is a southern Andes volcano that has been inflating since early 2012, with intermittent summit eruptive activity since late 2012. We have an extensive InSAR time series from RADARSAT-2 and COSMO-SkyMed data, although both are

  19. Diagnosing Dementia—Positive Signs

    Science.gov (United States)

    ... Navigation Bar Home Current Issue Past Issues Diagnosing Dementia—Positive Signs Past Issues / Fall 2007 Table of ... easy, affordable blood test that could accurately diagnose Alzheimer's disease (AD)—even before symptoms began to show? Researchers ...

  20. Spatially Resolved Measurements Of Plasma Density Irregularities In The Ionosphere F Region For Scintillation Studies.

    Science.gov (United States)

    Spencer, E. A.; Russ, S.; Clark, D. C.; Latif, S.; Montalvo, C.

    2016-12-01

    This qualitative study focuses on students evidence-based explanatory models on how ocean acidification impacts oysters. Explanatory models are the crucial components of scientific endeavors as it helps scientists explain how the natural world functions and the reasons for the ways it functions. Moreover, these models assemble individual practices to understand how they work together to reach clear conclusions through scientific investigations. Due to their critical roles in making sense of authentic science, recent studies in science education suggest that these models should be part of the curriculum aligned with new science standards, i.e. Next Generation Science Standards, which stress the importance of engaging students in scientific practices. By collecting data from 400 secondary school students in Maryland, we aim to respond to the question: How can we use secondary school students' explanatory models to provide students with constructive feedback for more comprehensive learning of ocean acidification (the related evidence, causes and impact)? The data were analyzed through discourse analysis method. We highlighted and coded students' inscriptions (e.g., drawings, writings, and representations) that are signs of students' understanding (or lack thereof) of ocean acidification. These signs included explanations of pH levels, drawings of oyster growth, and inclusions of relevant data. The findings showed that the explanatory models can be critical forms of feedback as they reveal a) students' alternative conceptions on how ocean acidification impacts oysters or how acidification works in general; b) students' interpretations of oceans' (non)connectedness to Earth system; c) the choice of scientific representations and their sources; and d) the way students' integrate evidence or data from the investigations. Our work tackles an understanding of one of the most vital signs of modern climatic changes. Recent scientific evidence shows that if the change in ocean pH becomes too extreme, many organisms may not be able to adjust to this change. Based on our findings, we suggest that teachers can use explanatory models as sources of feedback to recognize how well their students conceptualize ocean acidification, integrate scientific practices, and use cultural artifacts of doing science.

  1. Construction of theoretical F-spread ionogams from scattering in the HF band from field-aligned irregularities

    International Nuclear Information System (INIS)

    Powers, W.J.

    1985-01-01

    The scattering and propagation of electromagnetic fields in the ionosphere for the HF band is considered. Particular attention is given to scattering at the geomagnetic equator from irregularities of ionization density that are aligned along the earth's magnetic field and that have lengths that are much greater than a Fresnel scale. Perpendicular to the earth's magnetic field the irregularities are assumed to be isotropic with scale lengths (wavelengths /(2π)) extending from an inner scale equal to the ionic gyroradius to an outer scale on the order of the scale height of the ionosphere. Primary emphasis is placed on the weak scattering of pulses from field-aligned irregularities embedded in the night time F-layer, with application to explaining F-spread ionograms. The average ionization density of the night time F-layer is assumed to be well modeled by a parabolic layer. Assuming that the effects of the earth's magnetic field and collisions can be neglected, an approximate dyadic Green's function is derived and utilized in the determination of the incident and singly scattered fields

  2. Wettability measurements of irregular shapes with Wilhelmy plate method

    Science.gov (United States)

    Park, Jaehyung; Pasaogullari, Ugur; Bonville, Leonard

    2018-01-01

    One of the most accurate methods for measuring the dynamic contact angle of liquids on solid surfaces is the Wilhelmy plate method. This method generally requires the use of rectangular samples having a constant perimeter in the liquid during advancing and receding cycles. A new formulation based on the Wilhelmy force balance equation to determine the contact angle for plate samples with irregular shapes has been developed. This method employs a profile plot obtained from an optical image to determine the perimeter (i.e. wetted length) of the sample as a function of the immersion depth. The raw force data measured by the force tensiometer is manipulated using the profile plot and the Wilhelmy equation to determine the wetting force and consequently advancing and the receding contact angle. This method is verified with both triangular and irregular PTFE samples in water, and measured contact angles are in good agreement with results from conventional regular shaped samples with a constant perimeter.

  3. The scholarly rebellion of the early Baker Street Irregulars

    Directory of Open Access Journals (Sweden)

    George Mills

    2017-03-01

    Full Text Available This work provides and analyzes an early institutional history of the pioneering Sherlock Holmes American fan club, the Baker Street Irregulars (BSI. Using the publications and records of these devoted Sherlockians, I track the BSI's development from a speakeasy gathering in 1934 to a national organization by the mid-1940s. This growth was built on a foundation of Victorian nostalgia and playful humor. Yet at the same time the members of the Irregulars took their fandom seriously, producing Sherlockian scholarship and creating an infrastructure of journals, conferences, and credentialing that directly mimicked the academy. They positioned themselves in contrast to prevailing scholarly practices of the period, such as New Criticism. I trace both how their fan practices developed over time and how this conflict with the academy led to many of the BSI's defining characteristics.

  4. Constructing C1 Continuous Surface on Irregular Quad Meshes

    Institute of Scientific and Technical Information of China (English)

    HE Jun; GUO Qiang

    2013-01-01

    A new method is proposed for surface construction on irregular quad meshes as extensions to uniform B-spline surfaces. Given a number of control points, which form a regular or irregular quad mesh, a weight function is constructed for each control point. The weight function is defined on a local domain and is C1 continuous. Then the whole surface is constructed by the weighted combination of all the control points. The property of the new method is that the surface is defined by piecewise C1 bi-cubic rational parametric polynomial with each quad face. It is an extension to uniform B-spline surfaces in the sense that its definition is an analogy of the B-spline surface, and it produces a uniform bi-cubic B-spline surface if the control mesh is a regular quad mesh. Examples produced by the new method are also included.

  5. Visual nesting system for irregular cutting-stock problem based on rubber band packing algorithm

    Directory of Open Access Journals (Sweden)

    Xiaoping Liao

    2016-05-01

    Full Text Available This article deals with the packing problem of irregular items allocated into a rectangular sheet to minimize the waste. Conventional solution is not visual during the packing process. It obtains a reasonable and relatively satisfactory solution between the nesting time and nesting solution. This article adopts a physical method that uses rubber band packing algorithm to simulate a rubber band wrapping those packing irregular items. The simulation shows a visual and fast packing process. The resultant rubber band force is applied in the packing items to translate, rotate, and slide them to make the area decrease and obtain a high packing density. An improved analogy QuickHull algorithm is presented to obtain extreme points of rubber band convex hull. An adaptive module could set a variable rubber band force and a variable time step to make a proper convergence and no intersection. A quick convex decomposition method is used to solve the problem of concave polygon. A plural vector expression approach is adopted to calculate the resultant vector of the rubber band force. Several cases are compared with the benchmark problems to prove rubber band packing algorithm performance.

  6. Conflict Without Casualties: Non-Lethal Weapons in Irregular Warfare

    Science.gov (United States)

    2007-09-01

    the body,” and the Geneva Protocol of 1925, bans the use of chemical and biological weapons .11 On 8 April 1975, President Ford issued Executive...E Funding – PE 63851M) (accessed 15 December 2006). The American Journal of Bioethics . “Medical Ethics and Non-Lethal Weapons .” Bioethics.net...CASUALTIES: NON-LETHAL WEAPONS IN IRREGULAR WARFARE by Richard L. Scott September 2007 Thesis Advisor: Robert McNab Second Reader

  7. Active Absorption of Irregular Gravity Waves in BEM-Models

    DEFF Research Database (Denmark)

    Brorsen, Michael; Frigaard, Peter

    1992-01-01

    The boundary element method is applied to the computation of irregular gravity waves. The boundary conditions at the open boundaries are obtained by a digital filtering technique, where the surface elevations in front of the open boundary are filtered numerically yielding the velocity to be presc...... to be prescribed at the boundary. By numerical examples it is shown that well designed filters can reduce the wave reflection to a few per cent over a frequency range corresponding to a Jonswap spectrum....

  8. Using Little's Irregularity Index in orthodontics: outdated and inaccurate?

    LENUS (Irish Health Repository)

    Macauley, Donal

    2012-12-01

    Little\\'s Irregularity Index (LII) was devised to objectively score mandibular incisor alignment for epidemiological studies but has been extended to assess the relative performance of orthodontic brackets, retainer or treatment modalities. Our aim was to examine the repeatability and precision of LII measurements of four independent examiners on the maxillary arch of orthodontic patients. The hypothesis was that the reproducibility of individual contact point displacement measurements, used to calculate the LII score, are inappropriate.

  9. Computing Homology Group Generators of Images Using Irregular Graph Pyramids

    OpenAIRE

    Peltier , Samuel; Ion , Adrian; Haxhimusa , Yll; Kropatsch , Walter; Damiand , Guillaume

    2007-01-01

    International audience; We introduce a method for computing homology groups and their generators of a 2D image, using a hierarchical structure i.e. irregular graph pyramid. Starting from an image, a hierarchy of the image is built, by two operations that preserve homology of each region. Instead of computing homology generators in the base where the number of entities (cells) is large, we first reduce the number of cells by a graph pyramid. Then homology generators are computed efficiently on...

  10. Analysis of irregular opacities of silicosis using computed tomography

    International Nuclear Information System (INIS)

    Maeda, Atsushi; Shida, Hisao; Chiyotani, Keizo; Saito, Kenichi; Mishina, Michihito

    1983-01-01

    Classification in used to codify Chest CT images of abnormalities of the lung in a simple reproducible manner. Simbols to record CT features of importance are listed. We applied CT to 92 cases of silicosis and roentgenological analysis was performed. Bullae, honeycombing, cavity, emphysema, pleural thickning and calcification were more clearly demonstrated in CT images than routine chest roentgenograms. Irregular opacities were considered to be a combined profusion of small round and streak or strand. (author)

  11. Dynamics of landslides on comets of irregular shape

    Science.gov (United States)

    Czechowski, Leszek

    2017-04-01

    Landslides were observed on a few comet's nuclei, e.g. [1], [2]. The mechanism of their origin is not obvious because of very low gravity. According to [2] fluidization and multiphase transport of cometary material could be an explanation. We investigate here motion of the mass on a comet of irregular shape. The mechanism responsible for the low friction is not considered here. In fact, mass motion often occurs without contact with the surface. The motion could be triggered by meteoroids impacts or by the tidal forces. Comets nuclei are believed to be built of soft materials like snow and dust. The landing of Philae on the comet 67P/Czuriumow-Gierasimienko indicates a different situation. According to [1]: "thermal probe did not fully penetrate the near-surface layers, suggesting a local resistance of the ground to penetration of >4 megapascals, equivalent to >2 megapascal uniaxial compressive strength". Here we assume that elastic properties of comet's nuclei could be similar to elastic properties of dry snow, namely Young modulus is assumed to be 1 - 100 MPa, see [3] and [4]. We consider nucleus of the shape of 67P/Churyumov-Gerasimenko with density 470 kg/m3. The impact or tidal forces result in changing of rotation of the comet. In general, the vector of angular velocity will be a subject to nutation that results in changing of centrifugal force, and consequently could be a factor triggering landslides. Note that nucleus' shape does not resemble the shape of surface of constant value of gravitational potential (i.e. 'geoid'). Our numerical models indicate the parts of the nucleus where landslides start and other parts where landslides stop. Of course, the regolith from the first type of regions would be removed to the regions of the second class. The motion of the mass is often complicated because of complicated distribution of the gravity and complicated shape of the nucleus. Acknowledgement: The research is partly supported by Polish National Science Centre

  12. Use of dry-milling derived thin stillage for producing eicosapentaenoic acid (EPA) by the fungus Pythium irregulare.

    Science.gov (United States)

    Liang, Yi; Zhao, Xuefei; Strait, Megan; Wen, Zhiyou

    2012-05-01

    This study was to explore the use of thin stillage, a major byproduct in dry milling corn-ethanol plants, for production of eicosapentaenoic acid (EPA) by the fungus Pythium irregulare. Thin stillage contains various compounds that were ideal for fungal growth. Thin stillage concentration and temperature played important roles in fungal growth and EPA production. When 50% thin stillage was used in a stepwise temperature shift culture process, the cell density reached 23 g/L at day 9 with EPA yield and productivity of 243 and 27 mg/L day, respectively. The fungal biomass contained 39% lipid, 28% protein, 30% carbohydrate, and 3% ash. The fungal culture also generated a nutrient-depleted liquid by removing organic compounds in the raw thin stillage. The results collectively showed a new use of thin stillage by feeding to the fungus P. irregulare for producing omega-3 fatty acids. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. The Nature of Turbulence in the LITTLE THINGS Dwarf Irregular Galaxies

    Energy Technology Data Exchange (ETDEWEB)

    Maier, Erin; Chien, Li-Hsin; Hollyday, Gigja [Department of Physics and Astronomy, Northern Arizona University, NAU Box 6010, Flagstaff, AZ 86011 (United States); Elmegreen, Bruce G. [IBM T. J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, New York, NY 10598 (United States); Hunter, Deidre A. [Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States); Simpson, Caroline E. [Department of Physics, Florida International University, CP 204, 11200 SW 8th Street, Miami, FL 33199 (United States)

    2017-04-01

    We present probability density functions and higher order (skewness and kurtosis) analyses of the galaxy-wide and spatially resolved distributions of H i column density in the LITTLE THINGS sample of dwarf irregular galaxies. This analysis follows that of Burkhart et al. for the Small Magellanic Cloud (SMC). About 60% of our sample have galaxy-wide values of kurtosis that are similar to that found for the SMC, with a range up to much higher values, and kurtosis increases with integrated star formation rate. Kurtosis and skewness were calculated for radial annuli and for a grid of 32 pixel × 32 pixel kernels across each galaxy. For most galaxies, kurtosis correlates with skewness. For about half of the galaxies, there is a trend of increasing kurtosis with radius. The range of kurtosis and skewness values is modeled by small variations in the Mach number close to the sonic limit and by conversion of H i to molecules at high column density. The maximum H i column densities decrease with increasing radius in a way that suggests molecules are forming in the weak-field limit, where H{sub 2} formation balances photodissociation in optically thin gas at the edges of clouds.

  14. [Comparision of Different Methods of Area Measurement in Irregular Scar].

    Science.gov (United States)

    Ran, D; Li, W J; Sun, Q G; Li, J Q; Xia, Q

    2016-10-01

    To determine a measurement standard of irregular scar area by comparing the advantages and disadvantages of different measurement methods in measuring same irregular scar area. Irregular scar area was scanned by digital scanning and measured by coordinate reading method, AutoCAD pixel method, Photoshop lasso pixel method, Photoshop magic bar filled pixel method and Foxit PDF reading software, and some aspects of these methods such as measurement time, repeatability, whether could be recorded and whether could be traced were compared and analyzed. There was no significant difference in the scar areas by the measurement methods above. However, there was statistical difference in the measurement time and repeatability by one or multi performers and only Foxit PDF reading software could be traced back. The methods above can be used for measuring scar area, but each one has its advantages and disadvantages. It is necessary to develop new measurement software for forensic identification. Copyright© by the Editorial Department of Journal of Forensic Medicine

  15. Seismic performance for vertical geometric irregularity frame structures

    Science.gov (United States)

    Ismail, R.; Mahmud, N. A.; Ishak, I. S.

    2018-04-01

    This research highlights the result of vertical geometric irregularity frame structures. The aid of finite element analysis software, LUSAS was used to analyse seismic performance by focusing particularly on type of irregular frame on the differences in height floors and continued in the middle of the building. Malaysia’s building structures were affected once the earthquake took place in the neighbouring country such as Indonesia (Sumatera Island). In Malaysia, concrete is widely used in building construction and limited tension resistance to prevent it. Analysing structural behavior with horizontal and vertical static load is commonly analyses by using the Plane Frame Analysis. The case study of this research is to determine the stress and displacement in the seismic response under this type of irregular frame structures. This study is based on seven-storey building of Clinical Training Centre located in Sungai Buloh, Selayang, Selangor. Since the largest earthquake occurs in Acheh, Indonesia on December 26, 2004, the data was recorded and used in conducting this research. The result of stress and displacement using IMPlus seismic analysis in LUSAS Modeller Software under the seismic response of a formwork frame system states that the building is safe to withstand the ground and in good condition under the variation of seismic performance.

  16. Diagnosing suffering: a perspective.

    Science.gov (United States)

    Cassell, E J

    1999-10-05

    The alleviation of suffering is crucial in all of medicine, especially in the care of the dying. Suffering cannot be treated unless it is recognized and diagnosed. Suffering involves some symptom or process that threatens the patient because of fear, the meaning of the symptom, and concerns about the future. The meanings and the fear are personal and individual, so that even if two patients have the same symptoms, their suffering would be different. The complex techniques and methods that physicians usually use to make a diagnosis, however, are aimed at the body rather than the person. The diagnosis of suffering is therefore often missed, even in severe illness and even when it stares physicians in the face. A high index of suspicion must be maintained in the presence of serious disease, and patients must be directly questioned. Concerns over the discomfort of listening to patients' severe distress are usually more than offset by the gratification that follows the intervention. Often, questioning and attentive listening, which take little time, are in themselves ameliorative. The information on which the assessment of suffering is based is subjective; this may pose difficulties for physicians, who tend to value objective findings more highly and see a conflict between the two kinds of information. Recent advances in understanding how physicians increase the utility of information and make inferences allow one to reliably use the subjective information on which the diagnosis and treatment of suffering depend. Knowing patients as individual persons well enough to understand the origin of their suffering and ultimately its best treatment requires methods of empathic attentiveness and nondiscursive thinking that can be learned and taught. The relief of suffering depends on physicians acquiring these skills.

  17. Irregular analytical errors in diagnostic testing - a novel concept.

    Science.gov (United States)

    Vogeser, Michael; Seger, Christoph

    2018-02-23

    In laboratory medicine, routine periodic analyses for internal and external quality control measurements interpreted by statistical methods are mandatory for batch clearance. Data analysis of these process-oriented measurements allows for insight into random analytical variation and systematic calibration bias over time. However, in such a setting, any individual sample is not under individual quality control. The quality control measurements act only at the batch level. Quantitative or qualitative data derived for many effects and interferences associated with an individual diagnostic sample can compromise any analyte. It is obvious that a process for a quality-control-sample-based approach of quality assurance is not sensitive to such errors. To address the potential causes and nature of such analytical interference in individual samples more systematically, we suggest the introduction of a new term called the irregular (individual) analytical error. Practically, this term can be applied in any analytical assay that is traceable to a reference measurement system. For an individual sample an irregular analytical error is defined as an inaccuracy (which is the deviation from a reference measurement procedure result) of a test result that is so high it cannot be explained by measurement uncertainty of the utilized routine assay operating within the accepted limitations of the associated process quality control measurements. The deviation can be defined as the linear combination of the process measurement uncertainty and the method bias for the reference measurement system. Such errors should be coined irregular analytical errors of the individual sample. The measurement result is compromised either by an irregular effect associated with the individual composition (matrix) of the sample or an individual single sample associated processing error in the analytical process. Currently, the availability of reference measurement procedures is still highly limited, but LC

  18. Women with minor menstrual irregularities have increased risk of preeclampsia and low birthweight in spontaneous pregnancies

    DEFF Research Database (Denmark)

    Bonnesen, Barbara; Oddgeirsdóttir, Hanna L; Naver, Klara Vinsand

    2016-01-01

    INTRODUCTION: Very few studies describe the obstetric and neonatal outcome of spontaneous pregnancies in women with irregular menstrual cycles. However, menstrual cycle irregularities are common and may be associated with increased risk, and women who develop pregnancy complications more frequent...

  19. Study of Track Irregularity Time Series Calibration and Variation Pattern at Unit Section

    Directory of Open Access Journals (Sweden)

    Chaolong Jia

    2014-01-01

    Full Text Available Focusing on problems existing in track irregularity time series data quality, this paper first presents abnormal data identification, data offset correction algorithm, local outlier data identification, and noise cancellation algorithms. And then proposes track irregularity time series decomposition and reconstruction through the wavelet decomposition and reconstruction approach. Finally, the patterns and features of track irregularity standard deviation data sequence in unit sections are studied, and the changing trend of track irregularity time series is discovered and described.

  20. Irregular Liesegang-type patterns in gas phase revisited. II. Statistical correlation analysis

    Science.gov (United States)

    Torres-Guzmán, José C.; Martínez-Mekler, Gustavo; Müller, Markus F.

    2016-05-01

    We present a statistical analysis of Liesegang-type patterns formed in a gaseous HCl-NH3 system by ammonium chloride precipitation along glass tubes, as described in Paper I [J. C. Torres-Guzmán et al., J. Chem. Phys. 144, 174701 (2016)] of this work. We focus on the detection and characterization of short and long-range correlations within the non-stationary sequence of apparently irregular precipitation bands. To this end we applied several techniques to estimate spatial correlations stemming from different fields, namely, linear auto-correlation via the power spectral density, detrended fluctuation analysis (DFA), and methods developed in the context of random matrix theory (RMT). In particular RMT methods disclose well pronounced long-range correlations over at least 40 bands in terms of both, band positions and intensity values. By using a variant of the DFA we furnish proof of the nonlinear nature of the detected long-range correlations.

  1. Errors in determination of irregularity factor for distributed parameters in a reactor core

    International Nuclear Information System (INIS)

    Vlasov, V.A.; Zajtsev, M.P.; Il'ina, L.I.; Postnikov, V.V.

    1988-01-01

    Two types errors (measurement error and error of regulation of reactor core distributed parameters), offen met during high-power density reactor operation, are analyzed. Consideration is given to errors in determination of irregularity factor for radial power distribution for a hot channel under conditions of its minimization and for the conditions when the regulation of relative power distribution is absent. The first regime is investigated by the method of statistic experiment using the program of neutron-physical calculation optimization taking as an example a large channel water cooled graphite moderated reactor. It is concluded that it is necessary, to take into account the complex interaction of measurement error with the error of parameter profiling over the core both for conditions of continuous manual or automatic parameter regulation (optimization) and for the conditions without regulation namely at a priore equalized distribution. When evaluating the error of distributed parameter control

  2. Hydrostatic models of gas in clusters in an unsteady state in the irregular field

    International Nuclear Information System (INIS)

    Sidorov, K.A.

    1985-01-01

    A study is made of the hydrostatic distribution of gas in a system in a steady state in the regular field but an unsteady one in the irregular field. Such a system has a velocity distribution with mean square of the radial velocity greater than the mean square of the transversal. Clusters of galaxies probably have such a structure. It is found that the connection between the densities of the gas and the galaxies established by Cavaliere and Fusco-Femiano also holds for isothermal gas in the considered system. Hydrostatic equilibrium of the gas does not hold for clusters with very large asymmetry of the velocity distribution function of the galaxies. The surface brightness of the x-ray emission of the gas is calculated

  3. Numerical simulations of type II gradient drift irregularities in the equatorial electrojet

    International Nuclear Information System (INIS)

    Ferch, R.L.; Sudan, R.N.

    1977-01-01

    Two-dimensional numerical studies of the development of type II irregularities in the equatorial electrojet have been carried out using a method similar to that of McDonald et al., (1974) except that ion inertia has been neglected. This simplification is shown to be a valid approximation whenever the electron drift velocity is small in comparison with the ion acoustic velocity and the values of the other parameters are those appropriate for the equatorial E layer. This code enables us to follow the development of quasi-steady state turbulence from appropriate initial pertubations. The two-dimensional turbulent spectrum of electron density perturbations excited is studied both for the case of devlopment from initial perturbations and for the case of a continuously pumped single driving wave

  4. Identification of nursing management diagnoses.

    Science.gov (United States)

    Morrison, R S

    1997-02-01

    Theories from nursing and management provide frameworks for enhancing effectiveness of nursing management practice. The concept nursing management diagnosis has been developed by integrating nursing diagnosis and organizational diagnosis as a basis for nurse manager decision-making. Method triangulation was used to identify problems of managing nursing units, to validate those problems for relevancy to practice, to generate nursing management diagnoses, and to validate the diagnoses. Diagnoses were validated according to a definition of nursing management diagnosis provided. Of the 72 nursing management diagnoses identified, 66 were validated at a 70% level of agreement by nurse managers participating in the study.

  5. Kilometer-Spaced GNSS Array for Ionospheric Irregularity Monitoring

    Science.gov (United States)

    Su, Yang

    This dissertation presents automated, systematic data collection, processing, and analysis methods for studying the spatial-temporal properties of Global Navigation Satellite Systems (GNSS) scintillations produced by ionospheric irregularities at high latitudes using a closely spaced multi-receiver array deployed in the northern auroral zone. The main contributions include 1) automated scintillation monitoring, 2) estimation of drift and anisotropy of the irregularities, 3) error analysis of the drift estimates, and 4) multi-instrument study of the ionosphere. A radio wave propagating through the ionosphere, consisting of ionized plasma, may suffer from rapid signal amplitude and/or phase fluctuations known as scintillation. Caused by non-uniform structures in the ionosphere, intense scintillation can lead to GNSS navigation and high-frequency (HF) communication failures. With specialized GNSS receivers, scintillation can be studied to better understand the structure and dynamics of the ionospheric irregularities, which can be parameterized by altitude, drift motion, anisotropy of the shape, horizontal spatial extent and their time evolution. To study the structuring and motion of ionospheric irregularities at the sub-kilometer scale sizes that produce L-band scintillations, a closely-spaced GNSS array has been established in the auroral zone at Poker Flat Research Range, Alaska to investigate high latitude scintillation and irregularities. Routinely collecting low-rate scintillation statistics, the array database also provides 100 Hz power and phase data for each channel at L1/L2C frequency. In this work, a survey of seasonal and hourly dependence of L1 scintillation events over the course of a year is discussed. To efficiently and systematically study scintillation events, an automated low-rate scintillation detection routine is established and performed for each day by screening the phase scintillation index. The spaced-receiver technique is applied to cross

  6. Similarity estimators for irregular and age uncertain time series

    Science.gov (United States)

    Rehfeld, K.; Kurths, J.

    2013-09-01

    Paleoclimate time series are often irregularly sampled and age uncertain, which is an important technical challenge to overcome for successful reconstruction of past climate variability and dynamics. Visual comparison and interpolation-based linear correlation approaches have been used to infer dependencies from such proxy time series. While the first is subjective, not measurable and not suitable for the comparison of many datasets at a time, the latter introduces interpolation bias, and both face difficulties if the underlying dependencies are nonlinear. In this paper we investigate similarity estimators that could be suitable for the quantitative investigation of dependencies in irregular and age uncertain time series. We compare the Gaussian-kernel based cross correlation (gXCF, Rehfeld et al., 2011) and mutual information (gMI, Rehfeld et al., 2013) against their interpolation-based counterparts and the new event synchronization function (ESF). We test the efficiency of the methods in estimating coupling strength and coupling lag numerically, using ensembles of synthetic stalagmites with short, autocorrelated, linear and nonlinearly coupled proxy time series, and in the application to real stalagmite time series. In the linear test case coupling strength increases are identified consistently for all estimators, while in the nonlinear test case the correlation-based approaches fail. The lag at which the time series are coupled is identified correctly as the maximum of the similarity functions in around 60-55% (in the linear case) to 53-42% (for the nonlinear processes) of the cases when the dating of the synthetic stalagmite is perfectly precise. If the age uncertainty increases beyond 5% of the time series length, however, the true coupling lag is not identified more often than the others for which the similarity function was estimated. Age uncertainty contributes up to half of the uncertainty in the similarity estimation process. Time series irregularity

  7. Similarity estimators for irregular and age-uncertain time series

    Science.gov (United States)

    Rehfeld, K.; Kurths, J.

    2014-01-01

    Paleoclimate time series are often irregularly sampled and age uncertain, which is an important technical challenge to overcome for successful reconstruction of past climate variability and dynamics. Visual comparison and interpolation-based linear correlation approaches have been used to infer dependencies from such proxy time series. While the first is subjective, not measurable and not suitable for the comparison of many data sets at a time, the latter introduces interpolation bias, and both face difficulties if the underlying dependencies are nonlinear. In this paper we investigate similarity estimators that could be suitable for the quantitative investigation of dependencies in irregular and age-uncertain time series. We compare the Gaussian-kernel-based cross-correlation (gXCF, Rehfeld et al., 2011) and mutual information (gMI, Rehfeld et al., 2013) against their interpolation-based counterparts and the new event synchronization function (ESF). We test the efficiency of the methods in estimating coupling strength and coupling lag numerically, using ensembles of synthetic stalagmites with short, autocorrelated, linear and nonlinearly coupled proxy time series, and in the application to real stalagmite time series. In the linear test case, coupling strength increases are identified consistently for all estimators, while in the nonlinear test case the correlation-based approaches fail. The lag at which the time series are coupled is identified correctly as the maximum of the similarity functions in around 60-55% (in the linear case) to 53-42% (for the nonlinear processes) of the cases when the dating of the synthetic stalagmite is perfectly precise. If the age uncertainty increases beyond 5% of the time series length, however, the true coupling lag is not identified more often than the others for which the similarity function was estimated. Age uncertainty contributes up to half of the uncertainty in the similarity estimation process. Time series irregularity

  8. Ionospheric wave and irregularity measurements using passive radio astronomy techniques

    International Nuclear Information System (INIS)

    Erickson, W.C.; Mahoney, M.J.; Jacobson, A.R.; Knowles, S.H.

    1988-01-01

    The observation of midlatitude structures using passive radio astronomy techniques is discussed, with particular attention being given to the low-frequency radio telescope at the Clark Lake Radio Observatory. The present telescope operates in the 10-125-MHz frequency range. Observations of the ionosphere at separations of a few kilometers to a few hundreds of kilometers by the lines of sight to sources are possible, allowing the determination of the amplitude, wavelength, direction of propagation, and propagation speed of ionospheric waves. Data are considered on large-scale ionospheric gradients and the two-dimensional shapes and sizes of ionospheric irregularities. 10 references

  9. Analysis of an Irregular RC Multi-storeyed Building Subjected to Dynamic Loading

    Science.gov (United States)

    AkashRaut; Pachpor, Prabodh; Dautkhani, Sanket

    2018-03-01

    Many buildings in the present scenario have irregular configurations both in plan and elevation. This in future may subject to devastating earthquakes. So it is necessary to analyze the structure. The present paper is made to study three type of irregularity wiz vertical, mass and plan irregularity as per clause 7.1 of IS 1893 (part1)2002 code. The paper discusses the analysis of RC (Reinforced Concrete) Buildings with vertical irregularity. The study as a whole makes an effort to evaluate the effect of vertical irregularity on RC buildings for which comparison of three parameters namely shear force, bending moment and deflection are taken into account.

  10. Validation of nursing management diagnoses.

    Science.gov (United States)

    Morrison, R S

    1995-01-01

    Nursing management diagnosis based on nursing and management science, merges "nursing diagnosis" and "organizational diagnosis". Nursing management diagnosis is a judgment about nursing organizational problems. The diagnoses provide a basis for nurse manager interventions to achieve outcomes for which a nurse manager is accountable. A nursing organizational problem is a discrepancy between what should be happening and what is actually happening that prevents the goals of nursing from being accomplished. The purpose of this study was to validate 73 nursing management diagnoses identified previously in 1992: 71 of the 72 diagnoses were considered valid by at least 70% of 136 participants. Diagnoses considered to have high priority for future research and development were identified by summing the mean scores for perceived frequency of occurrence and level of disruption. Further development of nursing management diagnoses and testing of their effectiveness in enhancing decision making is recommended.

  11. Irregular Periapical Radiopacity in Mandibular Premolars and Molars

    Directory of Open Access Journals (Sweden)

    S. Aravind Warrier

    2014-01-01

    Full Text Available Increased deposition of cementum is observed in a wide number of both benign and malignant conditions. Many cases are often diagnosed during routine examination as an incidental finding. Diagnosing correctly without confusing it with other similarly appearing lesions, thus avoiding subjecting the patient to unnecessary investigations and stress, is of prime importance. We report one such case, where the patient presented with the routine complaint of a painful tooth, during the investigation of which he was also diagnosed with hypercementosis affecting the mandibular second premolars and molars bilaterally. The literature review reveals that not many cases of hypercementosis are frequently reported.

  12. Rocket in situ observation of equatorial plasma irregularities in the region between E and F layers over Brazil

    Directory of Open Access Journals (Sweden)

    S. Savio Odriozola

    2017-03-01

    Full Text Available A two-stage VS-30 Orion rocket was launched from the equatorial rocket launching station in Alcântara, Brazil, on 8 December 2012 soon after sunset (19:00 LT, carrying a Langmuir probe operating alternately in swept and constant bias modes. At the time of launch, ground equipment operated at equatorial stations showed rapid rise in the base of the F layer, indicating the pre-reversal enhancement of the F region vertical drift and creating ionospheric conditions favorable for the generation of plasma bubbles. Vertical profiles of electron density estimated from Langmuir probe data showed wave patterns and small- and medium-scale plasma irregularities in the valley region (100–300 km during the rocket upleg and downleg. These irregularities resemble those detected by the very high frequency (VHF radar installed at Jicamarca and so-called equatorial quasi-periodic echoes. We present evidence suggesting that these observations could be the first detection of this type of irregularity made by instruments onboard a rocket.

  13. Ionospheric Storm Effects and Equatorial Plasma Irregularities During the 17-18 March 2015 Event

    Science.gov (United States)

    Zhou, Yun-Liang; Luhr, Hermann; Xiong, Chao; Pfaff, Robert F.

    2016-01-01

    The intense magnetic storm on 17-18 March 2015 caused large disturbances of the ionosphere. Based on the plasma density (Ni) observations performed by the Swarm fleet of satellites, the Gravity Recovery and Climate Experiment mission, and the Communications/Navigation Outage Forecasting System satellite, we characterize the storm-related perturbations at low latitudes. All these satellites sampled the ionosphere in morning and evening time sectors where large modifications occurred. Modifications of plasma density are closely related to changes of the solar wind merging electric field (E (sub m)). We consider two mechanisms, prompt penetration electric field (PPEF) and disturbance dynamo electric field (DDEF), as the main cause for the Ni redistribution, but effects of meridional wind are also taken into account. At the start of the storm main phase, the PPEF is enhancing plasma density on the dayside and reducing it on the nightside. Later, DDEF takes over and causes the opposite reaction. Unexpectedly, there appears during the recovery phase a strong density enhancement in the morning/pre-noon sector and a severe Ni reduction in the afternoon/evening sector, and we suggest a combined effect of vertical plasma drift, and meridional wind is responsible for these ionospheric storm effects. Different from earlier studies about this storm, we also investigate the influence of storm dynamics on the initiation of equatorial plasma irregularities (EPIs). Shortly after the start of the storm main phase, EPIs appear in the post-sunset sector. As a response to a short-lived decline of E (sub m), EPI activity appears in the early morning sector. Following the second start of the main phase, EPIs are generated for a few hours in the late evening sector. However, for the rest of the storm main phase, no more EPIs are initiated for more than 12 hours. Only after the onset of recovery phase does EPI activity start again in the post-midnight sector, lasting more than 7 hours

  14. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Provider Pocket Guides Provider Guides Fertility Preservation for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed ... Patient Pocket Guides Patient Guides Fertility Preservation for Women Diagnosed with Cancer Fertility Preservation for Men Diagnosed ...

  15. Neuroblastoma in Children: Just Diagnosed Information

    Science.gov (United States)

    ... Financial Reports Watchdog Ratings Feedback Contact Select Page Neuroblastoma in Children – Just Diagnosed Home > Cancer Resources > Types ... Diagnosed Just Diagnosed In Treatment After Treatment Diagnosing Neuroblastoma Depending on the location of the tumor and ...

  16. The Biosynthetic Origin of Irregular Monoterpenes in Lavandula

    Science.gov (United States)

    Demissie, Zerihun A.; Erland, Lauren A. E.; Rheault, Mark R.; Mahmoud, Soheil S.

    2013-01-01

    Lavender essential oils are constituted predominantly of regular monoterpenes, for example linalool, 1,8-cineole, and camphor. However, they also contain irregular monoterpenes including lavandulol and lavandulyl acetate. Although the majority of genes responsible for the production of regular monoterpenes in lavenders are now known, enzymes (including lavandulyl diphosphate synthase (LPPS)) catalyzing the biosynthesis of irregular monoterpenes in these plants have not been described. Here, we report the isolation and functional characterization of a novel cis-prenyl diphosphate synthase cDNA, termed Lavandula x intermedia lavandulyl diphosphate synthase (LiLPPS), through a homology-based cloning strategy. The LiLPPS ORF, encoding for a 305-amino acid long protein, was expressed in Escherichia coli, and the recombinant protein was purified by nickel-nitrilotriacetic acid affinity chromatography. The approximately 34.5-kDa bacterially produced protein specifically catalyzed the head-to-middle condensation of two dimethylallyl diphosphate units to LPP in vitro with apparent Km and kcat values of 208 ± 12 μm and 0.1 s−1, respectively. LiLPPS is a homodimeric enzyme with a sigmoidal saturation curve and Hill coefficient of 2.7, suggesting a positive co-operative interaction among its catalytic sites. LiLPPS could be used to modulate the production of lavandulol and its derivatives in plants through metabolic engineering. PMID:23306202

  17. Size and Albedo of Irregular Saturnian Satellites from Spitzer Observations

    Science.gov (United States)

    Mueller, Michael; Grav, T.; Trilling, D.; Stansberry, J.; Sykes, M.

    2008-09-01

    Using MIPS onboard the Spitzer Space Telescope, we observed the thermal emission (24 and, for some targets, 70 um) of eight irregular satellites of Saturn: Albiorix, Siarnaq, Paaliaq, Kiviuq, Ijiraq, Tarvos, Erriapus, and Ymir. We determined the size and albedo of all targets. An analysis of archived MIPS observations of Phoebe reproduces Cassini results very accurately, thereby validating our method. For all targets, the geometric albedo is found to be low, probably below 10% and clearly below 15%. Irregular satellites are much darker than the large regular satellites. Their albedo is, however, quite similar to that of small bodies in the outer Solar System (such as cometary nuclei, Jupiter Trojans, or TNOs). This is consistent with color measurements as well as dynamical considerations which suggest a common origin of the said populations. There appear to be significant object-to-object albedo differences. Similar albedos found for some members of dynamical clusters support the idea that they may have originated in the breakup of a parent body. For three satellites, thermal data at two wavelengths are available, enabling us to constrain their thermal properties. Sub-solar temperatures are similar to that found from Cassini's Phoebe fly-by. This suggests a rather low thermal inertia, as expected for regolith-covered objects. This work is based on observations made with the Spitzer Space Telescope, which is operated by JPL under a contract with NASA. Support for this work was provided by NASA.

  18. Non-storm irregular variation of the Dst index

    Directory of Open Access Journals (Sweden)

    S. Nakano

    2012-01-01

    Full Text Available The Dst index has a long-term variation that is not associated with magnetic storms. We estimated the long-term non-storm component of the Dst variation by removing the short-term variation related to magnetic storms. The results indicate that the variation of the non-storm component includes not only a seasonal variation but also an irregular variation. The irregular long-term variation is likely to be due to an anti-correlation with the long-term variation of solar-wind activity. In particular, a clear anti-correlation is observed between the non-storm component of Dst and the long-term variation of the solar-wind dynamic pressure. This means that in the long term, the Dst index tends to increase when the solar-wind dynamic pressure decreases. We interpret this anti-correlation as an indication that the long-term non-storm variation of Dst is influenced by the tail current variation. The long-term variation of the solar-wind dynamic pressure controls the plasma sheet thermal pressure, and the change of the plasma sheet thermal pressure would cause the non-storm tail current variation, resulting in the non-storm variation of Dst.

  19. Irregular working hours and fatigue of cabin crew.

    Science.gov (United States)

    Castro, Marta; Carvalhais, José; Teles, Júlia

    2015-01-01

    Beyond workload and specific environmental factors, flight attendants can be exposed to irregular working hours, conflicting with their circadian rhythms and having a negative impact in sleep, fatigue, health, social and family life, and performance which is critical to both safety and security in flight operations. This study focuses on the irregular schedules of cabin crew as a trigger of fatigue symptoms in a wet lease Portuguese airline. The aim was to analyze: what are the requirements of the cabin crew work; whether the schedules being observed and effective resting timeouts are triggering factors of fatigue; and the existence of fatigue symptoms in the cabin crew. A questionnaire has been adapted and applied to a sample of 73 cabin crew-members (representing 61.9% of the population), 39 females and 34 males, with an average age of 27.68 ± 4.27 years. Our data indicate the presence of fatigue and corresponding health symptoms among the airline cabin crew, despite of the sample favorable characteristics. Senior workers and women are more affected. Countermeasures are required. Recommendations can be made regarding the fatigue risk management, including work organization, education and awareness training programmes and specific countermeasures.

  20. Model tracking dual stochastic controller design under irregular internal noises

    International Nuclear Information System (INIS)

    Lee, Jong Bok; Heo, Hoon; Cho, Yun Hyun; Ji, Tae Young

    2006-01-01

    Although many methods about the control of irregular external noise have been introduced and implemented, it is still necessary to design a controller that will be more effective and efficient methods to exclude for various noises. Accumulation of errors due to model tracking, internal noises (thermal noise, shot noise and l/f noise) that come from elements such as resistor, diode and transistor etc. in the circuit system and numerical errors due to digital process often destabilize the system and reduce the system performance. New stochastic controller is adopted to remove those noises using conventional controller simultaneously. Design method of a model tracking dual controller is proposed to improve the stability of system while removing external and internal noises. In the study, design process of the model tracking dual stochastic controller is introduced that improves system performance and guarantees robustness under irregular internal noises which can be created internally. The model tracking dual stochastic controller utilizing F-P-K stochastic control technique developed earlier is implemented to reveal its performance via simulation

  1. Using Radio Irregularity for Increasing Residential Energy Awareness

    Directory of Open Access Journals (Sweden)

    A. Miljković

    2012-06-01

    Full Text Available Radio irregularity phenomenon is often considered as a shortcoming of wireless networks. In this paper, the method of using radio irregularity as an efficient human presence detection sensor in smart homes is presented. The method is mainly based on monitoring variations of the received signal strength indicator (RSSI within the messages used for the communication between wireless smart power outlets. The radio signals used for the inter-outlets communication can be absorbed, diffracted or reflected by objects in their propagation paths. When a human enters the existing radio communication field, the variation of the signal strength at the receiver is even more expressed. Based on the detected changes and compared to the initial thresholds set during the initialization phase, the system detects human presence. The proposed solution increases user awareness and automates the power control in households, with the primary goal to contribute in residential energy savings. Compared to conventional sensor networks, this approach preserves the sensorial intelligence, simplicity and low installation costs, without the need for additional sensors integration.

  2. Colombia: la guerra irregular en el fin de siglo

    Directory of Open Access Journals (Sweden)

    Alfredo RANGEL SUÁREZ

    2009-11-01

    Full Text Available RESUMEN: El artículo analiza las transformaciones de la guerra irregular de las guerrillas colombianas en las últimas décadas. Para ello, se estudian los cambios que han afectado a distintos factores, como los objetivos estratégicos, los medios financieros, militares, las relaciones que mantienen con los partidos políticos tradicionales en el nivel local, sus parámetros ideológicos, el origen social de sus miembros. Con esta perspectiva, se analiza el cálculo político/temporal que la guerrilla hace en la actual coyuntura y sus consecuencias para el proceso de paz.ABSTRACT: This article examines the transformations of the irregular war of the colombian guerrillas, studying the changes of several factors such as the strategic goals, the financial and army resources, the relationship among the political parties in the local level, the evolution of their ideological parameters and of the social origin of their members. With this perspectiva, the author analyses temporal and political calculation that the guerrilla makes at this point, and its consequences for the peace process.

  3. Nonadiabatic two-electron transfer mediated by an irregular bridge

    International Nuclear Information System (INIS)

    Petrov, E.G.; Shevchenko, Ye.V.; May, V.

    2004-01-01

    Nonadiabatic two-electron transfer (TET) mediated by a linear molecular bridge is studied theoretically. Special attention is put on the case of a irregular distribution of bridge site energies as well as on the inter-site Coulomb interaction. Based on the unified description of electron transfer reactions [J. Chem. Phys. 115 (2001) 7107] a closed set of kinetic equations describing the TET process is derived. A reduction of this set to a single exponential donor-acceptor (D-A) TET is performed together with a derivation of an overall D-A TET rate. The latter contains a contribution of the stepwise as well as of the concerted route of D-A TET. The stepwise contribution is determined by two single-electron steps each of them associated with a sequential and a superexchange pathway. A two-electron unistep superexchange transition between the D and A forms the concerted contribution to the overall rate. Both contributions are analyzed in their dependency on the bridge length. The irregular distribution of the bridge site energies as well as the influence of the Coulomb interaction facilitates the D-A TET via a modification of the stepwise and the concerted part of the overall rate. At low temperatures and for short bridges with a single or two units the concerted contribution exceeds the stepwise contribution. If the bridge contains more than two units, the stepwise contribution dominates the overall rate

  4. Designing Next Generation Massively Multithreaded Architectures for Irregular Applications

    Energy Technology Data Exchange (ETDEWEB)

    Tumeo, Antonino; Secchi, Simone; Villa, Oreste

    2012-08-31

    Irregular applications, such as data mining or graph-based computations, show unpredictable memory/network access patterns and control structures. Massively multi-threaded architectures with large node count, like the Cray XMT, have been shown to address their requirements better than commodity clusters. In this paper we present the approaches that we are currently pursuing to design future generations of these architectures. First, we introduce the Cray XMT and compare it to other multithreaded architectures. We then propose an evolution of the architecture, integrating multiple cores per node and next generation network interconnect. We advocate the use of hardware support for remote memory reference aggregation to optimize network utilization. For this evaluation we developed a highly parallel, custom simulation infrastructure for multi-threaded systems. Our simulator executes unmodified XMT binaries with very large datasets, capturing effects due to contention and hot-spotting, while predicting execution times with greater than 90% accuracy. We also discuss the FPGA prototyping approach that we are employing to study efficient support for irregular applications in next generation manycore processors.

  5. THE INFRARED SPECTRA OF VERY LARGE IRREGULAR POLYCYCLIC AROMATIC HYDROCARBONS (PAHs): OBSERVATIONAL PROBES OF ASTRONOMICAL PAH GEOMETRY, SIZE, AND CHARGE

    International Nuclear Information System (INIS)

    Bauschlicher, Charles W.; Peeters, Els; Allamandola, Louis J.

    2009-01-01

    The mid-infrared (IR) spectra of six large, irregular polycyclic aromatic hydrocarbons (PAHs) with formulae (C 84 H 24 -C 120 H 36 ) have been computed using density functional theory (DFT). Trends in the dominant band positions and intensities are compared to those of large, compact PAHs as a function of geometry, size, and charge. Irregular edge moieties that are common in terrestrial PAHs, such as bay regions and rings with quartet hydrogens, are shown to be uncommon in astronomical PAHs. As for all PAHs comprised solely of C and H reported to date, mid-IR emission from irregular PAHs fails to produce a strong CC str band at 6.2 μm, the position characteristic of the important, class A astronomical PAH spectra. Earlier studies showed that inclusion of nitrogen within a PAH shifts this to 6.2 μm for PAH cations. Here we show that this band shifts to 6.3 μm in nitrogenated PAH anions, close to the position of the CC stretch in class B astronomical PAH spectra. Thus, nitrogenated PAHs may be important in all sources and the peak position of the CC stretch near 6.2 μm appears to directly reflect the PAH cation to anion ratio. Large irregular PAHs exhibit features at 7.8 μm but lack them near 8.6 μm. Hence, the 7.7 μm astronomical feature is produced by a mixture of small and large PAHs while the 8.6 μm band can only be produced by large compact PAHs. As with the CC str , the position and profile of these bands reflect the PAH cation to anion ratio.

  6. How Are Learning Disabilities Diagnosed?

    Science.gov (United States)

    ... Research Information Research Goals Activities and Advances Scientific Articles Find a Study Resources and Publications For Patients and Consumers For Researchers and Health Care Providers Home Health A to Z List Learning Disabilities Condition Information How is it diagnosed? Share ...

  7. Common Diagnoses in the NICU

    Science.gov (United States)

    ... breakdown of blood cells, and the liver usually "recycles" it back into the body). Although mild jaundice ... brain). However, PVL can happen without any previous history of bleeding. How is it diagnosed? Often no ...

  8. How to diagnose cardiac tamponade

    NARCIS (Netherlands)

    van Steijn, JHM; Sleijfer, DT; van der Graaf, WTA; van der Sluis, A; Nieboer, P

    Malignant pericardial effusion is a potentially fatal complication of malignancy unless recognised and treated promptly. Patients with this condition are often difficult to diagnose. Physical examination, chest radiography and electrocardiography have poor diagnostic values in identification of

  9. Diagnosing method for nuclear power plant

    International Nuclear Information System (INIS)

    Sonoda, Yukio.

    1991-01-01

    When an abnormality occurs in a nuclear power plant, the abnormality is diagnosed, at present, graphic waveforms obtained by applying signal processing such as high speed Fourier transformation, etc. to fluctuation ingredients (noises) of process signals such as neutron fluxes, and plotting a power spectral density relative to a frequency. However, expert technical knowledges are required for interpreting the waveforms and it is difficult for field operators and persons for maintenance to judge them. Then, in the present invention, patterns of the power spectral density are inputted for pattern recognition by using a neural net so that any of patterns experienced in the past can be identified. If an unknown pattern appears, it is automatically studied for identification in subsequent cases. Then, the known abnormality of the plant can be monitored and causes thereof can be identified in an early stage, as well as it is possible to diagnose unknown abnormalities in subsequent situation. This method is effective for monitoring and maintaining the integrity, and can avoid unnecessary scram to improve plant operation factor. (N.H.)

  10. Solo dwarfs I: survey introduction and first results for the Sagittarius dwarf irregular galaxy

    Science.gov (United States)

    Higgs, C. R.; McConnachie, A. W.; Irwin, M.; Bate, N. F.; Lewis, G. F.; Walker, M. G.; Côté, P.; Venn, K.; Battaglia, G.

    2016-05-01

    We introduce the Solitary Local dwarfs survey (Solo), a wide-field photometric study targeting every isolated dwarf galaxy within 3 Mpc of the Milky Way. Solo is based on (u)gi multiband imaging from Canada-France-Hawaii Telescope/MegaCam for northern targets, and Magellan/Megacam for southern targets. All galaxies fainter than MV ≃ -18 situated beyond the nominal virial radius of the Milky Way and M31 (≳300 kpc) are included in this volume-limited sample, for a total of 42 targets. In addition to reviewing the survey goals and strategy, we present results for the Sagittarius dwarf irregular galaxy (Sag DIG), one of the most isolated, low-mass galaxies, located at the edge of the Local Group. We analyse its resolved stellar populations and their spatial distributions. We provide updated estimates of its central surface brightness and integrated luminosity, and trace its surface brightness profile to a level fainter than 30 mag arcsec-2. Sag DIG is well described by a highly elliptical (disc-like) system following a single component Sérsic model. However, a low-level distortion is present at the outer edges of the galaxy that, were Sag DIG not so isolated, would likely be attributed to some kind of previous tidal interaction. Further, we find evidence of an extremely low level, extended distribution of stars beyond ˜5 arcmin (>1.5 kpc) that suggests Sag DIG may be embedded in a very low-density stellar halo. We compare the stellar and H I structures of Sag DIG, and discuss results for this galaxy in relation to other isolated, dwarf irregular galaxies in the Local Group.

  11. Coordinated observations of postmidnight irregularities and thermospheric neutral winds and temperatures at low latitudes

    Science.gov (United States)

    Dao, Tam; Otsuka, Yuichi; Shiokawa, Kazuo; Nishioka, Michi; Yamamoto, Mamoru; Buhari, Suhaila M.; Abdullah, Mardina; Husin, Asnawi

    2017-07-01

    We investigated a postmidnight field-aligned irregularity (FAI) event observed with the Equatorial Atmosphere Radar at Kototabang (0.2°S, 100.3°E, dip latitude 10.4°S) in Indonesia on the night of 9 July 2010 using a comprehensive data set of both neutral and plasma parameters. We examined the rate of total electron content change index (ROTI) obtained from GPS receivers in Southeast Asia, airglow images detected by an all-sky imager, and thermospheric neutral winds and temperatures obtained by a Fabry-Perot interferometer at Kototabang. Altitudes of the F layer (h'F) observed by ionosondes at Kototabang, Chiang Mai, and Chumphon were also surveyed. We found that the postmidnight FAIs occurred within plasma bubbles and coincided with kilometer-scale plasma density irregularities. We also observed an enhancement of the magnetically equatorward thermospheric neutral wind at the same time as the increase of h'F at low-latitude stations, but h'F at a station near the magnetic equator remained invariant. Simultaneously, a magnetically equatorward gradient of thermospheric temperature was identified at Kototabang. The convergence of equatorward neutral winds from the Northern and Southern Hemispheres could be associated with a midnight temperature maximum occurring around the magnetic equator. Equatorward neutral winds can uplift the F layer at low latitudes and increase the growth rate of Rayleigh-Taylor instabilities, causing more rapid extension of plasma bubbles. The equatorward winds in both hemispheres also intensify the eastward Pedersen current, so a large polarization electric field generated in the plasma bubble might play an important role in the generation of postmidnight FAIs.

  12. Compensation for unfavorable characteristics of irregular individual shift rotas.

    Science.gov (United States)

    Knauth, Peter; Jung, Detlev; Bopp, Winfried; Gauderer, Patric C; Gissel, Andreas

    2006-01-01

    Some employees of TV companies, such as those who produce remote TV programs, have to cope with very irregular rotas and many short-term schedule deviations. Many of these employees complain about the negative effects of such on their wellbeing and private life. Therefore, a working group of employers, council representatives, and researchers developed a so-called bonus system. Based on the criteria of the BESIAK system, the following list of criteria for the ergonomic assessment of irregular shift systems was developed: proportion of night hours worked between 22 : 00 and 01 : 00 h and between 06 : 00 and 07 : 00 h, proportion of night hours worked between 01 : 00 and 06 : 00 h, number of successive night shifts, number of successive working days, number of shifts longer than 9 h, proportion of phase advances, off hours on weekends, work hours between 17 : 00 and 23 : 00 h from Monday to Friday, number of working days with leisure time at remote places, and sudden deviations from the planned shift rota. Each individual rota was evaluated in retrospect. If pre-defined thresholds of criteria were surpassed, bonus points were added to the worker's account. In general, more bonus points add up to more free time. Only in particular cases was monetary compensation possible for some criteria. The bonus point system, which was implemented in the year 2002 for about 850 employees of the TV company, has the advantages of more transparency concerning the unfavorable characteristics of working-time arrangements, incentive for superiors to design "good" rosters that avoid the bonus point thresholds (to reduce costs), positive short-term effects on the employee social life, and expected positive long-term effects on the employee health. In general, the most promising approach to cope with the problems of shift workers in irregular and flexible shift systems seems to be to increase their influence on the arrangement of working times. If this is not possible, bonus point systems

  13. Road density

    Data.gov (United States)

    U.S. Environmental Protection Agency — Road density is generally highly correlated with amount of developed land cover. High road densities usually indicate high levels of ecological disturbance. More...

  14. Serum lipid levels and steroidal hormones in women runners with irregular menses.

    Science.gov (United States)

    Thompson, D L; Snead, D B; Seip, R L; Weltman, J Y; Rogol, A D; Weltman, A

    1997-02-01

    This study compared the lipid profile of women runners with menstrual cycle irregularities with their normally menstruating counterparts. Relationships among selected steroid hormones and serum lipid levels in 10 eumenorrheic (EU) and 8 oligo-/amenorrheic (O/A) women runners and 6 eumenorrheic controls (CON) were examined. Serum 17 beta-estradiol (E2), progesterone (Prog), and dehydroepiandrosterone-sulfate (DHEAS) concentrations were determined in daily blood samples for 21 days, and integrated concentrations were calculated. Fasting blood samples were analyzed for total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), HDL2, HDL3, triglycerides (Trig), and apolipoproteins A-1, A-II, and B. The O/A group had significantly lower E2 and Prog than EU or CON groups. Women in the CON group had lower HDL-C and HDL3 than the runners. With all women grouped together, E2 was not significantly correlated with any measured blood lipid parameters. On the other hand, DHEAS was significantly correlated with HDL-C, HDL2, and apolipoprotein A-I. These data demonstrate that women runners, regardless of menstrual cycle status, exhibit higher HDL-C concentrations than CON and supports previous research reporting a positive association between DHEAS and HDL-C.

  15. Airway surface irregularities promote particle diffusion in the human lung

    International Nuclear Information System (INIS)

    Martonen, T.; North Carolina Univ., Chapel Hill, NC; Zhang, Z.; Yang, Y.; Bottei, G.

    1995-01-01

    Current NCRP and ICRP particle deposition models employed in risk assessment analyses treat the airways of the human lung as smooth-walled tubes. However, the upper airways of the tracheobronchial (TB) tree are line with cartilaginous rings. Recent supercomputer simulations of in vivo conditions (cited herein), where cartilaginous ring morphologies were based upon fibre-optic bronchoscope examinations, have clearly demonstrated their profound effects upon fluid dynamics. A physiologically based analytical model of fluid dynamics is presented, focusing upon applications to particle diffusion within the TB tree. The new model is the first to describe particle motion while simultaneously simulating effects of wall irregularities, entrance conditions and tube curvatures. This study may explain the enhanced deposition by particle diffusion detected in replica case experiments and have salient implications for the clinically observed preferential distributions of bronchogenic carcinomas associated with inhaled radionuclides. (author)

  16. Massive stars in the Sagittarius Dwarf Irregular Galaxy

    Science.gov (United States)

    Garcia, Miriam

    2018-02-01

    Low metallicity massive stars hold the key to interpret numerous processes in the past Universe including re-ionization, starburst galaxies, high-redshift supernovae, and γ-ray bursts. The Sagittarius Dwarf Irregular Galaxy [SagDIG, 12+log(O/H) = 7.37] represents an important landmark in the quest for analogues accessible with 10-m class telescopes. This Letter presents low-resolution spectroscopy executed with the Gran Telescopio Canarias that confirms that SagDIG hosts massive stars. The observations unveiled three OBA-type stars and one red supergiant candidate. Pending confirmation from high-resolution follow-up studies, these could be the most metal-poor massive stars of the Local Group.

  17. Evaluation of Surface Slope Irregularity in Linear Parabolic Solar Collectors

    Directory of Open Access Journals (Sweden)

    F. Francini

    2012-01-01

    Full Text Available The paper describes a methodology, very simple in its application, for measuring surface irregularities of linear parabolic collectors. This technique was principally developed to be applied in cases where it is difficult to use cumbersome instruments and to facilitate logistic management. The instruments to be employed are a digital camera and a grating. If the reflector surface is defective, the image of the grating, reflected on the solar collector, appears distorted. Analyzing the reflected image, we can obtain the local slope of the defective surface. These profilometric tests are useful to identify and monitor the mirror portions under mechanical stress and to estimate the losses caused by the light rays deflected outside the absorber.

  18. Constructing a logical, regular axis topology from an irregular topology

    Science.gov (United States)

    Faraj, Daniel A.

    2014-07-01

    Constructing a logical regular topology from an irregular topology including, for each axial dimension and recursively, for each compute node in a subcommunicator until returning to a first node: adding to a logical line of the axial dimension a neighbor specified in a nearest neighbor list; calling the added compute node; determining, by the called node, whether any neighbor in the node's nearest neighbor list is available to add to the logical line; if a neighbor in the called compute node's nearest neighbor list is available to add to the logical line, adding, by the called compute node to the logical line, any neighbor in the called compute node's nearest neighbor list for the axial dimension not already added to the logical line; and, if no neighbor in the called compute node's nearest neighbor list is available to add to the logical line, returning to the calling compute node.

  19. Irregularities of ionospheric VTEC during lightning activity over Antarctic Peninsula

    International Nuclear Information System (INIS)

    Suparta, W; Wan Mohd Nor, W N A

    2017-01-01

    This paper investigates the irregularities of vertical total electron content (VTEC) during lightning activity and geomagnetic quiet days over Antarctic Peninsula in year 2014. During the lightning event, the ionosphere may be disturbed which may cause disruption in the radio signal. Thus, it is important to understand the influence of lightning on VTEC in the study of upper-lower interaction. The lightning data is obtained from World Wide Lightning Location Network (WWLLN) and the VTEC data has analyzed from Global Positioning System (GPS) for O’Higgins (OHI3), Palmer (PALV), and Rothera (ROTH). The results demonstrate the VTEC variation of ∼0.2 TECU during low lightning activity which could be caused by energy dissipation through lightning discharges from troposphere into the thermosphere. (paper)

  20. Global scale ionospheric irregularities associated with thunderstorm activity

    International Nuclear Information System (INIS)

    Pulinets, Sergey A.; Depuev, Victor H.

    2003-01-01

    The potential difference near 280 kV exists between ground and ionosphere. This potential difference is generated by thunderstorm discharges all over the world, and return current closes the circuit in the areas of fair weather (so-called fair weather current). The model calculations and experimental measurements clearly demonstrate non-uniform latitude-longitude distribution of electric field within the atmosphere. The recent calculations show that the strong large scale vertical atmospheric electric field can penetrate into the ionosphere and create large scale irregularities of the electron concentration. To check this the global distributions of thunderstorm activity obtained with the satellite monitoring for different seasons were compared with the global distributions of ionosphere critical frequency (which is equivalent to peak electron concentration) obtained with the help of satellite topside sounding. The similarity of the obtained global distributions clearly demonstrates the effects of thunderstorm electric fields onto the Earth's ionosphere. (author)

  1. Global scale ionospheric irregularities associated with thunderstorm activity

    CERN Document Server

    Pulinets, S A

    2002-01-01

    The potential difference near 280 kV exists between ground and ionosphere. This potential difference is generated by thunderstorm discharges all over the world, and return current closes the circuit in the areas of fair weather (so-called fair weather current). The model calculations and experimental measurements clearly demonstrate non-uniform latitude-longitude distribution of electric field within the atmosphere. The recent calculations show that the strong large scale vertical atmospheric electric field can penetrate into the ionosphere and create large scale irregularities of the electron concentration. To check this the global distributions of thunderstorm activity obtained with the satellite monitoring for different seasons were compared with the global distributions of ionosphere critical frequency (which is equivalent to peak electron concentration) obtained with the help of satellite topside sounding. The similarity of the obtained global distributions clearly demonstrates the effects of thunderstor...

  2. Asymmetry and irregularity border as discrimination factor between melanocytic lesions

    Science.gov (United States)

    Sbrissa, David; Pratavieira, Sebastião.; Salvio, Ana Gabriela; Kurachi, Cristina; Bagnato, Vanderlei Salvadori; Costa, Luciano Da Fontoura; Travieso, Gonzalo

    2015-06-01

    Image processing tools have been widely used in systems supporting medical diagnosis. The use of mobile devices for the diagnosis of melanoma can assist doctors and improve their diagnosis of a melanocytic lesion. This study proposes a method of image analysis for melanoma discrimination from other types of melanocytic lesions, such as regular and atypical nevi. The process is based on extracting features related with asymmetry and border irregularity. It were collected 104 images, from medical database of two years. The images were obtained with standard digital cameras without lighting and scale control. Metrics relating to the characteristics of shape, asymmetry and curvature of the contour were extracted from segmented images. Linear Discriminant Analysis was performed for dimensionality reduction and data visualization. Segmentation results showed good efficiency in the process, with approximately 88:5% accuracy. Validation results presents sensibility and specificity 85% and 70% for melanoma detection, respectively.

  3. Irregular Migration - between legal status and social practices

    DEFF Research Database (Denmark)

    Lund Thomsen, Trine

    2012-01-01

    Arnfinn H. and Rogstad, Jon 2.Book reviews by null 3.INVISIBLE IMMIGRANTS, VISIBLE EXPATS? Americans in Finnish discourses on immigration and internationalization by Leinonen, Johanna 4.Migrants in the Scandinavian Welfare State by Brochmann, Grete and Hagelund, Anniken 5.TOWARD AN IDENTITY STRESS....... Language and religious affiliations of an immigrant adolescent in Norway by Haque, Shahzaman View Top 20 Most Downloaded Articles Previous Article Next Article Go to table of contents Download full text pdf (PDF, 425 KB) Irregular Migration – Between Legal Status and Social Practices Narratives of Polish...... connected to the specific area of activity and to the accumulated capital of the individual. The aim is to identify how opportunity structures affect the migration process and how migrants react to them depending on the available capital and biographical knowledge and experiences. The horizon of experience...

  4. New Computational Approach to Electron Transport in Irregular Graphene Nanostructures

    Science.gov (United States)

    Mason, Douglas; Heller, Eric; Prendergast, David; Neaton, Jeffrey

    2009-03-01

    For novel graphene devices of nanoscale-to-macroscopic scale, many aspects of their transport properties are not easily understood due to difficulties in fabricating devices with regular edges. Here we develop a framework to efficiently calculate and potentially screen electronic transport properties of arbitrary nanoscale graphene device structures. A generalization of the established recursive Green's function method is presented, providing access to arbitrary device and lead geometries with substantial computer-time savings. Using single-orbital nearest-neighbor tight-binding models and the Green's function-Landauer scattering formalism, we will explore the transmission function of irregular two-dimensional graphene-based nanostructures with arbitrary lead orientation. Prepared by LBNL under contract DE-AC02-05CH11231 and supported by the U.S. Dept. of Energy Computer Science Graduate Fellowship under grant DE-FG02-97ER25308.

  5. Kriging for interpolation of sparse and irregularly distributed geologic data

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, K.

    1986-12-31

    For many geologic problems, subsurface observations are available only from a small number of irregularly distributed locations, for example from a handful of drill holes in the region of interest. These observations will be interpolated one way or another, for example by hand-drawn stratigraphic cross-sections, by trend-fitting techniques, or by simple averaging which ignores spatial correlation. In this paper we consider an interpolation technique for such situations which provides, in addition to point estimates, the error estimates which are lacking from other ad hoc methods. The proposed estimator is like a kriging estimator in form, but because direct estimation of the spatial covariance function is not possible the parameters of the estimator are selected by cross-validation. Its use in estimating subsurface stratigraphy at a candidate site for geologic waste repository provides an example.

  6. Towards intrinsic magnetism of graphene sheets with irregular zigzag edges.

    Science.gov (United States)

    Chen, Lianlian; Guo, Liwei; Li, Zhilin; Zhang, Han; Lin, Jingjing; Huang, Jiao; Jin, Shifeng; Chen, Xiaolong

    2013-01-01

    The magnetism of graphene has remained divergent and controversial due to absence of reliable experimental results. Here we show the intrinsic magnetism of graphene edge states revealed based on unidirectional aligned graphene sheets derived from completely carbonized SiC crystals. It is found that ferromagnetism, antiferromagnetism and diamagnetism along with a probable superconductivity exist in the graphene with irregular zigzag edges. A phase diagram is constructed to show the evolution of the magnetism. The ferromagnetic ordering curie-temperature of the fundamental magnetic order unit (FMOU) is 820 ± 80 K. The antiferromagnetic ordering Neel temperature of the FMOUs belonging to different sublattices is about 54 ± 2 K. The diamagnetism is similar to that of graphite and can be well described by the Kotosonov's equation. Our experimental results provide new evidences to clarify the controversial experimental phenomena observed in graphene and contribute to a deeper insight into the nature of magnetism in graphene based system.

  7. Comparison of different dose calculation methods for irregular photon fields

    International Nuclear Information System (INIS)

    Zakaria, G.A.; Schuette, W.

    2000-01-01

    In this work, 4 calculation methods (Wrede method, Clarskon method of sector integration, beam-zone method of Quast and pencil-beam method of Ahnesjoe) are introduced to calculate point doses in different irregular photon fields. The calculations cover a typical mantle field, an inverted Y-field and different blocked fields for 4 and 10 MV photon energies. The results are compared to those of measurements in a water phantom. The Clarkson and the pencil-beam method have been proved to be the methods of equal standard in relation to accuracy. Both of these methods are being distinguished by minimum deviations and applied in our clinical routine work. The Wrede and beam-zone methods deliver useful results to central beam and yet provide larger deviations in calculating points beyond the central axis. (orig.) [de

  8. Using the androgen excess-PCOS society criteria to diagnose polycystic ovary syndrome and the risk of metabolic syndrome in adolescents.

    Science.gov (United States)

    Roe, Andrea Hsu; Prochaska, Erica; Smith, Matthew; Sammel, Mary; Dokras, Anuja

    2013-05-01

    To use the Androgen Excess-PCOS Society (AE-PCOS) criteria in adolescents to diagnose polycystic ovary syndrome (PCOS) and identify the prevalence of metabolic risk factors. Retrospective chart review of adolescents (>2 years postmenarche) presenting at a specialty clinic from 2008 through 2010 with complete evaluation for PCOS and metabolic risk were reviewed. Metabolic risk in adolescents with PCOS was compared with those with ≤ 1 AE-PCOS criteria. Of the 205 adolescents evaluated, 66% were found to have PCOS based on the AE-PCOS criteria. The most common presenting symptom was menstrual irregularity, followed by acne, hirsutism, and weight gain. Adolescents with PCOS had a significantly higher prevalence of obesity, hypertension, and low level of high-density lipoprotein cholesterol. Subjects with PCOS had ≥ 1 metabolic risk factor compared with the subjects without PCOS (63.6% vs 33.3%, P = .002). More adolescents with PCOS had ≥ 2 abnormal metabolic risk factors excluding body mass index compared with those without PCOS (P PCOS compared with 1.7% in those without PCOS (P PCOS based on the AE-PCOS criteria are at a significantly increased risk of ≥ 1 metabolic abnormality. Our data underscore the need to accurately diagnose PCOS in the adolescent population instead of delaying the diagnosis to adulthood. Further, using similar criteria for the diagnosis of PCOS in adolescents (>2 years postmenarche) and adults will be more convenient for the clinician. Copyright © 2013 Mosby, Inc. All rights reserved.

  9. Experimental Study of Irregular Waves on a Gravel Beach

    Science.gov (United States)

    Hu, Nai-Ren; Wu, Yun-Ta; Hwung, Hwung-Hweng; Yang, Ray-Yeng

    2017-04-01

    In the east coast of Taiwan, the sort grain size more belongs to cobble or gravel, which is physically distinct compared to the sandy beach in the west coast of Taiwan. Although gravel beaches can dissipate more of wave energy, gravel beaches were eroded and coastal road were damaged especially during typhoons. The purpose of this study is to investigate the geomorphological response of gravel beach due to irregular waves. This experiment was carry out in a 21m long, 50 cm wide, 70 cm high wave tank at Tainan Hydraulics Laboratory, National Cheng-Kung University, Taiwan. To simulate of the geometry in the east coast of Taiwan, a physical model with 1/36 scale-down was used, in which the seawall was 10cm built upon a 1:10 slope and gravel grains with D50 being 3.87 mm was nourished in front of the seawall. In terms of typhoon-scale wave condition, irregular waves with scale-down conditions were generated for 600 s for each scenarios and, three different water levels with respect to the gravel beach are designed. Application of laser combined with image processing to produce 3D topographic map, the erosion zone and accretion zone would be found. The resulting morphological change of gravel beach will be measured using an integrated laser and image processing tool to have 3D topographic maps. It is expected to have more understanding about under what conditions the gravel coasts suffer the least damage. In particular, the relation between erosion rates of gravel beach, the angle of gravel slope and the length of the plane on the gravel slope will be achieved

  10. Tamoxifen treatment of bleeding irregularities associated with Norplant use.

    Science.gov (United States)

    Abdel-Aleem, Hany; Shaaban, Omar M; Amin, Ahmed F; Abdel-Aleem, Aly M

    2005-12-01

    To evaluate the possible role of tamoxifen (selective estrogen receptor modulators, SERM) in treating bleeding irregularities associated with Norplant contraceptive use. Randomized clinical trial including 100 Norplant users complaining of vaginal bleeding irregularities. The trial was conducted in the Family Planning Clinic of Assiut University Hospital. Women were assigned at random to receive tamoxifen tablets (10 mg) twice daily for 10 days or similar placebo. Women were followed-up for 3 months. The end points were percentage of women who stopped bleeding during treatment, bleeding/spotting days during the period of follow-up, effect of treatment on their lifestyle, and side effects and discontinuation of contraception. There was good compliance with treatment. At the end of treatment, a significantly higher percentage of tamoxifen users stopped bleeding in comparison to the control group (88% vs. 68%, respectively; p=.016). Women who used tamoxifen had significantly less bleeding and/or spotting days than women who used placebo, during the first and second months. During the third month, there were no significant differences between the two groups. Women who used tamoxifen reported improvement in performing household activities, religious duties and in sexual life, during the first 2 months. In the third month, there were no differences between the two groups. There were no significant differences between tamoxifen and placebo groups in reporting side effects. In the group who used tamoxifen, two women discontinued Norplant use because of bleeding vs. nine women in the placebo group. Tamoxifen use at a dose of 10 mg twice daily orally, for 10 days, has a beneficial effect on vaginal bleeding associated with Norplant use. In addition, the bleeding pattern was better in women who used tamoxifen for the following 2 months after treatment. However, these results have to be confirmed in a larger trial before advocating this line of treatment.

  11. ESA' s novel gravitational modeling of irregular planetary bodies

    Science.gov (United States)

    Ortega, Guillermo

    A detailed understanding and modeling of the gravitational modeling is required for realistic investigation of the dynamics of orbits close to irregularly shaped bodies. Gravity field modelling up to a certain maximum spherical harmonic degree N involves N2 unkown spherical harmonic coefficients or complex harmonics. The corresponding number of matrix entries reaches till N4 . For missions like CHAMP, GRACE or GOCE, the maximum degree of resolution is 75, 150 and 300 respectively. Therefore, the number of unknowns for a satellite like GOCE will be around 100.000. Since these missions usually fly for a period of time of several years, the number of observations is huge. Hence, gravity field recovery from these missions is a high demanding task. The classical approaches like spherical expansion of the potential lead generally to a high number of coefficients, which reduce the software computational efficiency of the orbit propagation and which have mostly a limited physical meaning. One of the main targets of the activity is the modelling of asteroids, small moons, and cometary bodies. All celestial bodies are irregular by definition. However, the scope of the activity is broad enough as to be able to use the models and the software in quasy-regular bodies as well. Therefore the models and tools could be used for bodies such as the Moon, Mars, Venus, Deimos, Europa, Eros, Mathilda, and Churyumov-Gerasimenko, etc., being these applications relevant for scientific (Rosetta, Bepi Colombo), exploration (Exo-Mars), NEO mitigation (Don Quijote) and Earth observation (GOCE) missions of ESA.

  12. Volume determination of irregularly-shaped quasi-spherical nanoparticles.

    Science.gov (United States)

    Attota, Ravi Kiran; Liu, Eileen Cherry

    2016-11-01

    Nanoparticles (NPs) are widely used in diverse application areas, such as medicine, engineering, and cosmetics. The size (or volume) of NPs is one of the most important parameters for their successful application. It is relatively straightforward to determine the volume of regular NPs such as spheres and cubes from a one-dimensional or two-dimensional measurement. However, due to the three-dimensional nature of NPs, it is challenging to determine the proper physical size of many types of regularly and irregularly-shaped quasi-spherical NPs at high-throughput using a single tool. Here, we present a relatively simple method that determines a better volume estimate of NPs by combining measurements from their top-down projection areas and peak heights using two tools. The proposed method is significantly faster and more economical than the electron tomography method. We demonstrate the improved accuracy of the combined method over scanning electron microscopy (SEM) or atomic force microscopy (AFM) alone by using modeling, simulations, and measurements. This study also exposes the existence of inherent measurement biases for both SEM and AFM, which usually produce larger measured diameters with SEM than with AFM. However, in some cases SEM measured diameters appear to have less error compared to AFM measured diameters, especially for widely used IS-NPs such as of gold, and silver. The method provides a much needed, proper high-throughput volumetric measurement method useful for many applications. Graphical Abstract The combined method for volume determination of irregularly-shaped quasi-spherical nanoparticles.

  13. Reproducibility of irregular radiation fields for malignant lymphoma

    International Nuclear Information System (INIS)

    Mock, U.; Dieckmann, K.; Poetter, R.; Molitor, A.M.; Haverkamp, U.

    1998-01-01

    Purpose: Radiation treatment for malignant lymphoma requires large field irradiation with irregular blocks according to the individual anatomy and tumor configuration. For determination of safety margins (PTV) we quantitatively analysed the accuracy of field and block placement with regard to different anatomical regions. Patients and Methods: Forty patients with malignant lymphoma were irradiated using the classical supra-/infradiaphragmatic field arrangements. Treatment was performed with 10-MeV photons and irregularly shaped, large opposing fields. We evaluated the accuracy of field and block placements during the treatment courses by comparing the regularly performed verification - with the simulation films. Deviations were determined with respect to the field edges and the central axis, along the x- and z-axis. Results: With regard to the field edges, mean deviations of 2.0 mm and 3.4 mm were found along the x- and z-axis. The corresponding standard deviations were 3.4 mm and 5.5 mm, respectively. With regard to the shielding blocks, mean displacement along the x- and z-axis was 2.2 mm and 3.8 mm. In addition, overall standard deviations of 5.7 mm (x-axis) and 7.1 mm (z-axis) were determined. During the course of time an improved accuracy of block placement was notable. Conclusion: Systematic analysis of port films gives information for a better defining safety margins in external radiotherapy. Evaluation of verification films on a regular basis improves set-up accuracy by reducing displacements. (orig.) [de

  14. Diagnoser

    DEFF Research Database (Denmark)

    Waaddegaard, Mette; Lau, Marianne Engelbrecht; Schousboe, Birgitte Hartvig

    2012-01-01

    Spiseforstyrrelser er psykiske sygdomme, hvor forholdet til mad, krop og spisning er så forstyrret, at det går ud over ens sundhed og sociale liv. Man skelner typisk mellem anoreksi, bulimi og tvangsoverspisning, men der findes næsten lige så mange kombinationer af spiseforstyrrelsessymptomer, som...

  15. Crime among irregular immigrants and the influence of internal border control

    OpenAIRE

    Leerkes, Arjen; Engbersen, Godfried; Leun, Joanne

    2012-01-01

    textabstractBoth the number of crime suspects without legal status and the number of irregular or undocumented immigrants held in detention facilities increased substantially in theNetherlands between 1997 and 2003. In this period, theDutch state increasingly attempted to exclude irregular immigrants from the formal labour market and public provisions. At the same time the registered crime among irregular migrants rose. The 'marginalisation thesis' asserts that a larger number of migrants hav...

  16. The reconciliation of an F-region irregularity model with sunspot-cycle variations in spread-F occurrence

    International Nuclear Information System (INIS)

    Singleton, D.G.

    1974-11-01

    A recently proposed means of combining models of ionospheric F-layer peak electron density and irregularity incremental electron density (ΔN) so as to simulate the global occurrence probability of the frequency spreading component of spread-F is discussed. This procedure is then used to model experimental spread-F occurrence results. It is found possible to readily simulate the sunspot-maximum results, independently of season, with only small adjustments to the amplitudes of the empirical expressions used to ΔN in the several latitude regimes. However, at sunspot minimum and for each season, the ΔN model requires modification in the equatorial and mid-latitude regions of high irregularity incidence, before successful simulations of the spread-F data can be obtained. These modifications, which include a broadening of the equatorial region and a polewards shift to the mid-latitude region with decreasing sunspot number, are discussed in detail. It is concluded that the scintillation data base, from which the original ΔN model derives, is not sufficiently representative with regard to sunspot number and magnetic index. The use of the spread-F adaptation of the ΔN model, as well as its original scintillation version, to rectify these failings of the ΔN model are also discussed. (author)

  17. Effects of magnetic storm phases on F layer irregularities below the auroral oval

    International Nuclear Information System (INIS)

    Aarons, J.; Gurgiolo, C.; Rodger, A.S.

    1988-01-01

    Observations of F-layer irregularity development and intensity were obtained between September and October 1981, primarily over subauroral latitudes in the area of the plasmapause. The results reveal the descent of the auroral irregularity region to include subauroral latitudes in the general area of the plasmapause during the main phases of a series of magnetic storms. Irregularities were found primarily at lower latitudes during the subauroral or plasmapause storm. A model for the subauroral irregularities in recovery phases of magnetic storms is proposed in which energy stored in the ring current is slowly released. 27 references

  18. Dependence on zenith angle of the strength of 3-meter equatorial electrojet irregularities

    International Nuclear Information System (INIS)

    Ierkic, H.M.; Fejer, B.G.; Farley, D.T.

    1980-01-01

    Radar measurements in Peru were used to deduce the zenith angle dependence of the scattering cross section of plasma irregularities generated by instabilities in the equatorial electrojet. The irregularities probed by the 50 MHz Jicamarca radar had a wavelength of 3m. The cross section for the type 2 irregularities was isotopic in the plane perpendicular to the magnetic field, while the cross section for the stronger type 1 irregularities varied with zenith angle at a rate of approximately 0.3 dB/degree; the horizontally traveling waves were more than 100 times stronger than those traveling vertically

  19. Nursing diagnoses in overweight adolescents

    Directory of Open Access Journals (Sweden)

    Raphaela Santos do Nascimento Rodrigues

    2013-05-01

    Full Text Available This study aimed to identify nursing diagnoses in overweight adolescents from public schools, according to the International Classification for Nursing Practice. A population-based cross-sectional study that investigated the socio-demographic, behavioural and psychological characteristics of adolescents aged from 10 to 14 years. 11 nursing diagnoses were identified: "Risk of overweight", "Risk of impaired adolescent development", "Risk of insecurity in parental role performance", "Risk of the family impaired ability to manage diet regime", "Risk of impaired ability to manage diet regime", "Risk of lack of knowledge of dietary regime", "Risk of excess food intake", "Risk of negative self-image", "Risk of low self-esteem", "Risk of impaired social well-being" and "Impaired exercise pattern". These diagnoses reflect the multifactorial nature of obesity, highlighting the need for interdisciplinary and intersectoral articulation of nursing interventions for prevention and control of overweight.

  20. Gaucher's disease diagnosed by splenectomy.

    Science.gov (United States)

    Adas, Mine; Adas, Gokhan; Karatepe, Oguzhan; Altiok, Merih; Ozcan, Deniz

    2009-08-01

    Splenectomy continues to find common therapeutic indications for hematologic disorders. In addition, recently it is also performed in surgical clinics to assist diagnose of some illnesses. Gaucher's disease, especially Type I, is the most frequently encountered lysosomal storage disorder in man. Manifestations of it are highly variable. The most frequently found symptoms include splenomegaly with anaemia and thrombocytopenia, mostly due to hypersplenism, hepatomegaly and bone disease. Four patients were reported in the present study. Three of them were easily diagnosed with Gaucher's disease via bone marrow cytology, and one with Gaucher's disease was detected by pathological examination following the splenectomy. For the pouse of diagnosis of the Gaucher's disease, performing surgery is generally not necessary. However, for the cases of difficult to diagnose by classical methods, the corect diagnosis of Gaucher's disease can only be made by a special operation.

  1. Psychiatric diagnoses, trauma, and suicidiality

    Directory of Open Access Journals (Sweden)

    Elklit Ask

    2007-04-01

    Full Text Available Abstract Background This study aimed to examine the associations between psychiatric diagnoses, trauma and suicidiality in psychiatric patients at intake. Methods During two months, all consecutive patients (n = 139 in a psychiatric hospital in Western Norway were interviewed (response rate 72%. Results Ninety-one percent had been exposed to at least one trauma; 69 percent had been repeatedly exposed to trauma for longer periods of time. Only 7% acquired a PTSD diagnosis. The comorbidity of PTSD and other psychiatric diagnoses were 78%. A number of diagnoses were associated with specific traumas. Sixty-seven percent of the patients reported suicidal thoughts in the month prior to intake; thirty-one percent had attempted suicide in the preceding week. Suicidal ideation, self-harming behaviour, and suicide attempts were associated with specific traumas. Conclusion Traumatised patients appear to be under- or misdiagnosed which could have an impact on the efficiency of treatment.

  2. Correlation of antemortem diagnoses and postmortem diagnoses in ...

    African Journals Online (AJOL)

    Background: The postmortem examination is a veritable means of ascertaining the correct diagnoses. Over the years, there has been a severe drop in the number of requests for postmortem examination despite its numerous advantages and benefits. The study is aimed at showing the pivotal role of the autopsy in medical ...

  3. Interhemispheric subdural empyema diagnosed by CT and cured by antibiotic therapy

    International Nuclear Information System (INIS)

    Hayakawa, Isao; Fukui, Mitsufumi; Furuhashi, Norihisa; Kanda, Tadashi; Tazaki, Yoshiaki

    1981-01-01

    A case of interhemispheric subdural empyema cured by high doses of antibiotics was reported. A 23-year-old man was admitted with complaints of headache, fever and motor weakness of the left lower leg of 2 days' duration. The neurological examination revealed neck stiffness, motor weakness and sensory disturbance of left lower leg. The WBS count was 26,000/cumm, and ESR was 74 mm/hour. The CSF showed a pressure of 230 mm H 2 O and contained 1001/3 cells (63% polymorphonuclears, 37% lymphocytes) in association with slight elevation of protein but with normal sugar content. The CSF culture was negative. Administration of high doses of antibiotics was started on the first hospital day. On the fourth hospital day, Jacksonian seizures occurred in the left lower extremity, and were controlled by anticonvulsants. CT scans with contrast enhancement revealed an area of low density in the right interhemispheric space with irregular marginal enhancement. Right carotid arteriography demonstrated a small oval avascular space along the interhemispheric cistern. The abnormalities on CT scan disappeared after one month, when the patient was discharged without neurological deficit. Unlike the previously reported cases with interhemispheric subdural empyema commonly associated with a collection of pus over the cerebral convexities, a localized interhemispheric subdural empyema as was found in the present case appears to be a very rare condition. The interhemispheric subdural empyema has been thought to be exclusively surgical indication and, to the best of our knowlage, there is no report in the literature of a case with successful medical treatment. However, successful treatment by antibiotics alone may become more practical if the diagnoses could be made in the early stage with the aid of CT scan. (author)

  4. Interhemispheric subdural empyema diagnosed by CT and cured by antibiotic therapy

    Energy Technology Data Exchange (ETDEWEB)

    Hayakawa, I.; Fukui, M.; Furuhashi, N.; Kanda, T.; Tazaki, Y. (Kitasato Univ., Sagamihara, Kanagawa (Japan). School of Medicine)

    1981-09-01

    A case of interhemispheric subdural empyema cured by high doses of antibiotics was reported. A 23-year-old man was admitted with complaints of headache, fever and motor weakness of the left lower leg of 2 days' duration. The neurological examination revealed neck stiffness, motor weakness and sensory disturbance of left lower leg. The WBS count was 26,000/cumm, and ESR was 74 mm/hour. The CSF showed a pressure of 230 mm H/sub 2/O and contained 1001/3 cells (63% polymorphonuclears, 37% lymphocytes) in association with slight elevation of protein but with normal sugar content. The CSF culture was negative. Administration of high doses of antibiotics was started on the first hospital day. On the fourth hospital day, Jacksonian seizures occurred in the left lower extremity, and were controlled by anticonvulsants. CT scans with contrast enhancement revealed an area of low density in the right interhemispheric space with irregular marginal enhancement. Right carotid arteriography demonstrated a small oval avascular space along the interhemispheric cistern. The abnormalities on CT scan disappeared after one month, when the patient was discharged without neurological deficit. Unlike the previously reported cases with interhemispheric subdural empyema commonly associated with a collection of pus over the cerebral convexities, a localized interhemispheric subdural empyema as was found in the present case appears to be a very rare condition. The interhemispheric subdural empyema has been thought to be exclusively surgical indication and, to the best of our knowlage, there is no report in the literature of a case with successful medical treatment. However, successful treatment by antibiotics alone may become more practical if the diagnoses could be made in the early stage with the aid of CT scan.

  5. Immunological methods for diagnosing neurocysticercosis

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, R.E.; Estrada, J.J.; Grogl, M.

    1989-01-31

    A method is described for diagnosing active human neurocysticercosis by detecting the presence of at least one Taenia solium larval antigen in cerebrospinal fluid, which comprises: contacting cerebrospinal fluid from a human to be diagnosed with a solid support, wherein the support binds with a Taenia solium larval antigen if present, contacting the support with a first antibody, wherein the first antibody binds with a larval Taenia solium antigen if present in the cerebrospinal fluid, contacting the solid support with a detectable second antibody which will bind with the first antibody, and detecting the second antibody bound to the support.

  6. Lung density

    DEFF Research Database (Denmark)

    Garnett, E S; Webber, C E; Coates, G

    1977-01-01

    The density of a defined volume of the human lung can be measured in vivo by a new noninvasive technique. A beam of gamma-rays is directed at the lung and, by measuring the scattered gamma-rays, lung density is calculated. The density in the lower lobe of the right lung in normal man during quiet...... breathing in the sitting position ranged from 0.25 to 0.37 g.cm-3. Subnormal values were found in patients with emphsema. In patients with pulmonary congestion and edema, lung density values ranged from 0.33 to 0.93 g.cm-3. The lung density measurement correlated well with the findings in chest radiographs...... but the lung density values were more sensitive indices. This was particularly evident in serial observations of individual patients....

  7. Diagnoses and interventions in podiatry.

    NARCIS (Netherlands)

    Zuijderduin, W.M.; Dekker, J.

    1996-01-01

    In the present study a quantitative description is given of diagnoses and interventions in podiatry. Data are used from a survey on podiatry practice in The Netherlands. Data have been recorded by 36 podiatrists on 897 patients. Information was gathered on patient characteristics, the medical

  8. Influence of Ionospheric Irregularities on GNSS Remote Sensing

    Directory of Open Access Journals (Sweden)

    M. V. Tinin

    2015-01-01

    Full Text Available We have used numerical simulation to study the effects of ionospheric irregularities on accuracy of global navigation satellite system (GNSS measurements, using ionosphere-free (in atmospheric research and geometry-free (in ionospheric research dual-frequency phase combinations. It is known that elimination of these effects from multifrequency GNSS measurements is handi-capped by diffraction effects during signal propagation through turbulent ionospheric plasma with the inner scale being smaller than the Fresnel radius. We demonstrated the possibility of reducing the residual ionospheric error in dual-frequency GNSS remote sensing in ionosphere-free combination by Fresnel inversion. The inversion parameter, the distance to the virtual screen, may be selected from the minimum of amplitude fluctuations. This suggests the possibility of improving the accuracy of GNSS remote sensing in meteorology. In the study of ionospheric disturbances with the aid of geometry-free combination, the Fresnel inversion eliminates only the third-order error. To eliminate the random TEC component which, like the measured average TEC, is the first-order correction, we should use temporal filtering (averaging.

  9. Timing irregularities of PSR J1705-1906

    Science.gov (United States)

    Liu, Y. L.; Yuan, J. P.; Wang, J. B.; Liu, X. W.; Wang, N.; Yuen, R.

    2018-05-01

    Timing analysis of PSR J1705-1906 using data from Nanshan 25-m and Parkes 64-m radio telescopes, which span over fourteen years, shows that the pulsar exhibits significant proper motion, and rotation instability. We updated the astrometry parameters and the spin parameters of the pulsar. In order to minimize the effect of timing irregularities on measuring its position, we employ the Cholesky method to analyse the timing noise. We obtain the proper motion of -77(3) mas yr-1 in right ascension and -38(29) mas yr-1 in declination. The power spectrum of timing noise is analyzed for the first time, which gives the spectral exponent α =-5.2 for the power-law model indicating that the fluctuations in spin frequency and spin-down rate dominate the red noise. We detect two small glitches from this pulsar with fractional jump in spin frequency of Δ ν /ν ˜ 2.9 × 10^{-10} around MJD 55199 and Δ ν /ν ˜ 2.7× 10^{-10} around MJD 55953. Investigations of pulse profile at different time segments suggest no significant changes in the pulse profiles around the two glitches.

  10. Distributed sensing of ionospheric irregularities with a GNSS receiver array

    Science.gov (United States)

    Su, Yang; Datta-Barua, Seebany; Bust, Gary S.; Deshpande, Kshitija B.

    2017-08-01

    We present analysis methods for studying the structuring and motion of ionospheric irregularities at the subkilometer scale sizes that produce L band scintillations. Spaced-receiver methods are used for Global Navigation Satellite System (GNSS) receivers' phase measurements over approximately subkilometer to kilometer length baselines for the first time. The quantities estimated by these techniques are plasma drift velocity, diffraction anisotropy magnitude and orientation, and characteristic velocity. Uncertainties are quantified by ensemble simulation of noise on the phase signals carried through to the observations of the spaced-receiver linear system. These covariances are then propagated through to uncertainties on drifts through linearization about the estimated values of the state. Five receivers of SAGA, the Scintillation Auroral Global Positioning System (GPS) Array, provide 100 Hz power and phase data for each channel at L1 frequency. The array is sited in the auroral zone at Poker Flat Research Range, Alaska. A case study of a single scintillating satellite observed by the array is used to demonstrate the spaced-receiver and uncertainty estimation process. A second case study estimates drifts as measured by multiple scintillating channels. These scintillations are correlated with auroral activity, based on all-sky camera images. Measurements and uncertainty estimates made over a 30 min period are compared to a collocated incoherent scatter radar and show good agreement in horizontal drift speed and direction during periods of scintillation for which the characteristic velocity is less than the drift velocity.

  11. Metallicity of Young and Old Stars in Irregular Galaxies

    Science.gov (United States)

    Tikhonov, N. A.

    2018-01-01

    Based on archived images obtained with the Hubble Space Telescope, stellar photometry for 105 irregular galaxies has been conducted. We have shown the red supergiant and giant branches in the obtained Hertzsprung-Russel diagrams. Using the TRGB method, distances to galaxies and metallicity of red giants have been determined. The color index ( V - I) of the supergiant branch at the luminosity level M I = -7 was chosen as the metallicity index of red supergiants. For the galaxies under study, the diagrams have been built, in which the correlation can be seen between the luminosity of galaxies ( M B ) and metallicity of red giants and supergiants. The main source of variance of the results in the obtained diagrams is, in our opinion, uncertainty inmeasurements of galaxy luminosities and star-forming outburst. The relation between metallicity of young and old stars shows that main enrichment of galaxies with metals has taken place in the remote past. Deviations of some galaxies in the obtained relation can possibly be explained with the fall of the intergalactic gas on them, although, this inconsiderably affects metallicities of the stellar content.

  12. Climatic irregular staircases: generalized acceleration of global warming.

    Science.gov (United States)

    De Saedeleer, Bernard

    2016-01-27

    Global warming rates mentioned in the literature are often restricted to a couple of arbitrary periods of time, or of isolated values of the starting year, lacking a global view. In this study, we perform on the contrary an exhaustive parametric analysis of the NASA GISS LOTI data, and also of the HadCRUT4 data. The starting year systematically varies between 1880 and 2002, and the averaging period from 5 to 30 yr - not only decades; the ending year also varies . In this way, we uncover a whole unexplored space of values for the global warming rate, and access the full picture. Additionally, stairstep averaging and linear least squares fitting to determine climatic trends have been sofar exclusive. We propose here an original hybrid method which combines both approaches in order to derive a new type of climatic trend. We find that there is an overall acceleration of the global warming whatever the value of the averaging period, and that 99.9% of the 3029 Earth's climatic irregular staircases are rising. Graphical evidence is also given that choosing an El Niño year as starting year gives lower global warming rates - except if there is a volcanic cooling in parallel. Our rates agree and generalize several results mentioned in the literature.

  13. Effects of Irregular Bridge Columns and Feasibility of Seismic Regularity

    Science.gov (United States)

    Thomas, Abey E.

    2018-05-01

    Bridges with unequal column height is one of the main irregularities in bridge design particularly while negotiating steep valleys, making the bridges vulnerable to seismic action. The desirable behaviour of bridge columns towards seismic loading is that, they should perform in a regular fashion, i.e. the capacity of each column should be utilized evenly. But, this type of behaviour is often missing when the column heights are unequal along the length of the bridge, allowing short columns to bear the maximum lateral load. In the present study, the effects of unequal column height on the global seismic performance of bridges are studied using pushover analysis. Codes such as CalTrans (Engineering service center, earthquake engineering branch, 2013) and EC-8 (EN 1998-2: design of structures for earthquake resistance. Part 2: bridges, European Committee for Standardization, Brussels, 2005) suggests seismic regularity criterion for achieving regular seismic performance level at all the bridge columns. The feasibility of adopting these seismic regularity criterions along with those mentioned in literatures will be assessed for bridges designed as per the Indian Standards in the present study.

  14. Irregular persistent activity induced by synaptic excitatory feedback

    Directory of Open Access Journals (Sweden)

    Francesca Barbieri

    2007-11-01

    Full Text Available Neurophysiological experiments on monkeys have reported highly irregular persistent activity during the performance of an oculomotor delayed-response task. These experiments show that during the delay period the coefficient of variation (CV of interspike intervals (ISI of prefrontal neurons is above 1, on average, and larger than during the fixation period. In the present paper, we show that this feature can be reproduced in a network in which persistent activity is induced by excitatory feedback, provided that (i the post-spike reset is close enough to threshold , (ii synaptic efficacies are a non-linear function of the pre-synaptic firing rate. Non-linearity between presynaptic rate and effective synaptic strength is implemented by a standard short-term depression mechanism (STD. First, we consider the simplest possible network with excitatory feedback: a fully connected homogeneous network of excitatory leaky integrate-and-fire neurons, using both numerical simulations and analytical techniques. The results are then confirmed in a network with selective excitatory neurons and inhibition. In both the cases there is a large range of values of the synaptic efficacies for which the statistics of firing of single cells is similar to experimental data.

  15. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... You are here Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation for Children Diagnosed with Cancer Ask Your Doctor Information for ...

  16. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation for Children Diagnosed with Cancer Ask Your Doctor Information for Patients Many adult ...

  17. "Needed Not Wanted": An Interdisciplinary Examination of the Work-Related Challenges Faced by Irregular Migrants

    Science.gov (United States)

    Marfleet, Philip; Blustein, David L.

    2011-01-01

    Using an integrative perspective drawn from vocational psychology and migration studies, this article explores the lives of irregular migrants, which represents a unique aspect of work-based migration. Irregular migrants are those individuals who travel from regions without much work to states that offer some means of employment, without formal…

  18. Lateralized effects of orthographical irregularity and auditory memory load on the kinematics of transciption typewriting

    NARCIS (Netherlands)

    Bloemsaat, J.G.; Galen, G.P. van; Meulenbroek, R.G.J.

    2003-01-01

    This study investigated the combined effects of orthographical irregularity and auditory memory load on the kinematics of finger movements in a transcription-typewriting task. Eight right-handed touch-typists were asked to type 80 strings of ten seven-letter words. In half the trials an irregularly

  19. The Relationships among Cognitive Correlates and Irregular Word, Non-Word, and Word Reading

    Science.gov (United States)

    Abu-Hamour, Bashir; University, Mu'tah; Urso, Annmarie; Mather, Nancy

    2012-01-01

    This study explored four hypotheses: (a) the relationships among rapid automatized naming (RAN) and processing speed (PS) to irregular word, non-word, and word reading; (b) the predictive power of various RAN and PS measures, (c) the cognitive correlates that best predicted irregular word, non-word, and word reading, and (d) reading performance of…

  20. Influence of initial stress, irregularity and heterogeneity on Love-type ...

    Indian Academy of Sciences (India)

    The present paper deals with the propagation of Love-type wave in an initially stressed irregular vertically heterogeneous layer lying over an initially stressed isotropic layer and an initially stressed isotropic half- space. Two different types of irregularities, viz., rectangular and parabolic, are considered at the interface.

  1. Crime among irregular immigrants and the influence of internal border control

    NARCIS (Netherlands)

    Leerkes, A.S.; Engbersen, G.; Leun, van der J.P.

    2012-01-01

    Abstract Both the number of crime suspects without legal status and the number of irregular or undocumented immigrants held in detention facilities increased substantially in theNetherlands between 1997 and 2003. In this period, theDutch state increasingly attempted to exclude irregular immigrants

  2. Crime among irregular immigrants and the influence of internal border control

    NARCIS (Netherlands)

    A.S. Leerkes (Arjen); G.B.M. Engbersen (Godfried); J.P. van der Leun (Joanne)

    2012-01-01

    textabstractBoth the number of crime suspects without legal status and the number of irregular or undocumented immigrants held in detention facilities increased substantially in theNetherlands between 1997 and 2003. In this period, theDutch state increasingly attempted to exclude irregular

  3. Breaking Down Anonymity: Digital surveillance on irregular migrants in Germany and the Netherlands

    NARCIS (Netherlands)

    D.W.J. Broeders (Dennis)

    2009-01-01

    textabstractThe presence of irregular migrants causes a tough problem for policy makers. Political and popular aversion against the presence of irregular migrants has mounted in most West-European societies for years, yet their presence remains. Their exact numbers are obviously unknown - only

  4. Dynamics of long-period irregular pulsations in high latitudes during strong magnetic storms

    International Nuclear Information System (INIS)

    Kurazhkovskaya, N.A.; Klajn, B.I.

    1995-01-01

    Effects of strong magnetic storms within np type high-latitudinal long-period irregular pulsations at Mirny studied using data obtained at observatory of the magnetosphere south hemisphere. Variation of long-period irregular pulsation amplitude is shown to depend essentially on duration of storm initial phase and on the nature of solar wind heterogeneity enabling growth of strong storm. 14 refs

  5. A Study of Two Dwarf Irregular Galaxies with Asymmetrical Star Formation Distributions

    Science.gov (United States)

    Hunter, Deidre A.; Gallardo, Samavarti; Zhang, Hong-Xin; Adamo, Angela; Cook, David O.; Oh, Se-Heon; Elmegreen, Bruce G.; Kim, Hwihyun; Kahre, Lauren; Ubeda, Leonardo; Bright, Stacey N.; Ryon, Jenna E.; Fumagalli, Michele; Sacchi, Elena; Kennicutt, R. C.; Tosi, Monica; Dale, Daniel A.; Cignoni, Michele; Messa, Matteo; Grebel, Eva K.; Gouliermis, Dimitrios A.; Sabbi, Elena; Grasha, Kathryn; Gallagher, John S., III; Calzetti, Daniela; Lee, Janice C.

    2018-03-01

    Two dwarf irregular galaxies, DDO 187 and NGC 3738, exhibit a striking pattern of star formation: intense star formation is taking place in a large region occupying roughly half of the inner part of the optical galaxy. We use data on the H I distribution and kinematics and stellar images and colors to examine the properties of the environment in the high star formation rate (HSF) halves of the galaxies in comparison with the low star formation rate halves. We find that the pressure and gas density are higher on the HSF sides by 30%–70%. In addition we find in both galaxies that the H I velocity fields exhibit significant deviations from ordered rotation and there are large regions of high-velocity dispersion and multiple velocity components in the gas beyond the inner regions of the galaxies. The conditions in the HSF regions are likely the result of large-scale external processes affecting the internal environment of the galaxies and enabling the current star formation there.

  6. In-Situ Measurement of Ionospheric E-Region Plasma Irregularities over Taiwan

    Directory of Open Access Journals (Sweden)

    Chi-Kuang Chao

    2012-01-01

    Full Text Available One ion trap (IT and one retarding potential analyzer (RPA onboard the Taiwan Sounding Rocket V (SR-V were launched to measure ionospheric plasma irregularities on 18 January 2006. After the fairing separated, voltage readings (VG1 of the first grid (G1 in the IT indicated abnormally high negative voltages appeared at the upleg between 83.7 and 120.1 km altitude for 19.7 seconds. It is postulated G1 had temporarily shorted out with the other two grids. Such the anomaly in the VG1 brought out the expansion of a plasma sheath around opening of the IT. More ions were attracted into the collector. Remarkable ion currents detected by the IT led to malfunctions of the RPA simultaneously. In this article, laboratory simulations and the International Reference Ionosphere model are performed to evaluate scale factors for the IT to the anomaly. The calibrated total ion concentration profile at the upleg indicates a peak density of the Es layer at 93.0 km altitude of about 6.9 × 103 # cm-3 with a thickness of 3.4 km. It is very similar to that at the downleg. It implies that the SR-V might encounter the same Es layer twice in a distance of 150 km away.

  7. Radar observations of artificial E-region field-aligned irregularities

    Directory of Open Access Journals (Sweden)

    E. Nossa

    2009-07-01

    Full Text Available Artificial E region field aligned plasma density irregularities (FAIs were generated using HAARP in four different experimental modes and observed with a coherent scatter radar imager located 450 km to the southwest where it could detect field-aligned backscatter. The experiments were conducted in July of 2008, during the Polar Aeronomy and Radio Science Summer School (PARS, during quiet conditions in the daytime when the E layer was dense and absorption was modest. The echoes observed during zenith and magnetic zenith heating experiments were deflected from their nominally anticipated horizontal positions toward the midpoint position. The occurrence of hysteresis when heating with amplitude modulated pulses implied the development of the resonance instability, although the threshold for the onset of instability appeared to be higher than what has been predicted theoretically. Heating experiments involving pump frequencies slightly above and below the second electron gyroharmonic frequency produced no significant differences in the observed echoes. Finally, heating with a pump frequency slightly above the E region critical frequency appears to have produced FAIs at two distinct altitudes where the upper-hybrid resonance condition could be satisfied.

  8. Large-scale irregularities of the winter polar topside ionosphere according to data from Swarm satellites

    Science.gov (United States)

    Lukianova, R. Yu.; Bogoutdinov, Sh. R.

    2017-11-01

    An analysis of the electron density measurements ( Ne) along the flyby trajectories over the high-latitude region of the Northern Hemisphere under winter conditions in 2014 and 2016 has shown that the main large-scale structure observed by Swarm satellites is the tongue of ionization (TOI). At the maximum of the solar cycle ( F 10.7 = 160), the average value of Ne in the TOI region at an altitude of 500 km was 8 × 104 cm-3. Two years later, at F 10.7 = 100, Ne 5 × 104 cm-3 and Ne 2.5 × 104 cm-3 were observed at altitudes of 470 and 530 km, respectively. During the dominance of the azimuthal component of the interplanetary magnetic field, the TOI has been observed mainly on the dawn or dusk side depending on the sign of B y . Simultaneous observations of the convective plasma drift velocity in the polar cap show the transpolar flow drift to the dawn ( B y y generation of large-scale irregularities in the polar ionosphere.

  9. New Opportunities for Remote Sensing Ionospheric Irregularities by Fitting Scintillation Spectra

    Science.gov (United States)

    Carrano, C. S.; Rino, C. L.; Groves, K. M.

    2017-12-01

    In a recent paper, we presented a phase screen theory for the spectrum of intensity scintillations when the refractive index irregularities follow a two-component power law [Carrano and Rino, DOI: 10.1002/2015RS005903]. More recently we have investigated the inverse problem, whereby phase screen parameters are inferred from scintillation time series. This is accomplished by fitting the spectrum of intensity fluctuations with a parametrized theoretical model using Maximum Likelihood (ML) methods. The Markov-Chain Monte-Carlo technique provides a-posteriori errors and confidence intervals. The Akaike Information Criterion (AIC) provides justification for the use of one- or two-component irregularity models. We refer to this fitting as Irregularity Parameter Estimation (IPE) since it provides a statistical description of the irregularities from the scintillations they produce. In this talk, we explore some new opportunities for remote sensing ionospheric irregularities afforded by IPE. Statistical characterization of irregularities and the plasma bubbles in which they are embedded provides insight into the development of the underlying instability. In a companion paper by Rino et al., IPE is used to interpret scintillation due to simulated EPB structure. IPE can be used to reconcile multi-frequency scintillation observations and to construct high fidelity scintillation simulation tools. In space-to-ground propagation scenarios, for which an estimate of the distance to the scattering region is available a-priori, IPE enables retrieval of zonal irregularity drift. In radio occultation scenarios, the distance to the irregularities is generally unknown but IPE enables retrieval of Fresnel frequency. A geometric model for the effective scan velocity maps Fresnel frequency to Fresnel scale, yielding the distance to the irregularities. We demonstrate this approach by geolocating irregularities observed by the CORISS instrument onboard the C/NOFS satellite.

  10. How to diagnose acute appendicitis

    DEFF Research Database (Denmark)

    Mostbeck, Gerhard; Adam, E Jane; Nielsen, Michael Bachmann

    2016-01-01

    appendicitis (AA). • Primary US for AA diagnosis will decrease ionizing radiation and cost. • Sensitivity of US to diagnose AA is lower than of CT/MRI. • Non-visualization of the appendix should lead to clinical reassessment. • Complementary MRI or CT may be performed if diagnosis remains unclear....... and complementary imaging with MRI/CT if indicated. Accordingly, both ionizing radiation to our patients and cost of pre-therapeutic diagnosis of AA will be low, with low negative appendectomy and perforation rates. Main Messages • Ultrasound (US) should be the first imaging modality for diagnosing acute...... specificity both in the paediatric and adult patient populations. As US sensitivity is limited, and non-diagnostic US examinations with non-visualization of the appendix are more a rule than an exception, diagnostic strategies and algorithms after non-diagnostic US should focus on clinical reassessment...

  11. Low and Mid-Latitude Ionospheric Irregularities Studies Using TEC and Radio Scintillation Data from the CITRIS Radio Beacon Receiver in Low-Earth-Orbit

    Science.gov (United States)

    Siefring, C. L.; Bernhardt, P. A.; Huba, J.; Krall, J.; Roddy, P. A.

    2009-12-01

    Unique data on ionospheric plasma irregularities from the Naval Research Laboratory (NRL) CITRIS (Scintillation and TEC Receiver in Space) instrument will be presented. CITRIS is a multi-band receiver that recorded TEC (Total Electron Content) and radio scintillations from Low-Earth Orbit (LEO) on STPSat1. The 555+/5 km altitude 35° inclination orbit covers low and mid-latitudes. The measurements require propagation from a transmitter to a receiver through the F-region plasma. CITRIS used both 1) satellite beacons in LEO, such as the NRL CERTO (Coherent Electromagnetic Radio TOmography) beacons and 2) the global network of ground-based DORIS (Doppler Orbitography and Radiopositioning Integrated by Satellite) beacons. The TEC measurements allow for tracking of ionospheric disturbances and irregularities while the measurements of scintillations can simultaneously characterize their effects. CITRIS was operated in a complementary fashion with the C/NOFS (Communication/Navigations Outages Forecasting System) satellite during most of its first year of operations. C/NOFS carries a three-frequency 150/400/1067 MHz CERTO beacon and is dedicated to the study of Spread-F. In the case of Spread-F, ionospheric irregularities start with large scale size density gradients (100s of km) and cascade through complex processes to short scale sizes (10s of meters). It is typically the 100m-1km scale features that harm communication and navigation systems through scintillations. A multi-sensor approach is needed to completely understand this complex system, such as, the combination of CITRIS remote radio sensing and C/NOFS in-situ data. Several types of irregularities have been studied including Spread-F and the newly discovered dawn-side depletions. Comparisons with the physics based SAMI3 model are being performed to help our understanding of the morphology of the irregularities.

  12. Feedback Limiting the Coastal Response to Irregularities in Shelf Bathymetry

    Science.gov (United States)

    List, J. H.; Benedet, L.

    2007-12-01

    Observations and engineering studies have shown that non-uniform inner shelf bathymetry can influence longshore sediment transport gradients and create patterns of shoreline change. One classic example is from Grand Isle, Louisiana, where two offshore borrow pits caused two zones of shoreline accretion landward of the pits. In addition to anthropogenic cases, many natural situations exist in which irregularities in coastal planform are thought to result from offshore shoals or depressions. Recent studies using the hydrodynamic model Delft3D have successfully simulated the observed nearshore erosion and accretion patterns landward of an inner shelf borrow pit. An analysis of the momentum balance in a steady-state simulation has demonstrated that both alongshore pressure gradients (due to alongshore variations in wave setup) and radiation stress gradients (terms relevant to alongshore forcing) are important for forcing the initial pattern of nearshore sedimentation in response to the borrow pit. The response of the coast to non-uniform inner shelf bathymetry appears to be limited, however, because observed shoreline undulations are often rather subtle. (An exception may exist in the case of a very high angle wave climate.) Therefore, feedbacks in processes must exist such that growth of the shoreline salient itself modifies the transport processes in a way that limits further growth (assuming the perturbation in inner shelf bathymetry itself remains unchanged). Examination of the Delft3D momentum balance for an inner shelf pit test case demonstrates that after a certain degree of morphologic development the forcing associated with the well-known shoreline smoothing process (a.k.a., diffusion) counteracts the forcing associated with the inner shelf pit, producing a negative feedback which arrests further growth of the shoreline salient. These results provide insights into the physical processes that control shoreline changes behind inner shelf bathymetric anomalies (i

  13. Periods, poles, and shapes of Saturn's irregular moons

    Science.gov (United States)

    Denk, Tilmann; Mottola, Stefano

    2016-10-01

    We report rotational-lightcurve observations of irregular moons of Saturn based on disk-integrated observations with the Narrow-Angle Camera of the Cassini spacecraft. From 24 measured rotation periods, 20 are now known with an accuracy of ~2% or better. The numbers are as follows (in hours; an '*' marks the less reliable periods): Hati 5.42; Mundilfari 6.74; Loge 6.94*; Skoll 7.26; Kari 7.70; Suttungr 7.82*, Bergelmir 8.13; Phoebe 9.274; Siarnaq 10.188; Narvi 10.21; Tarvos 10.69; Skathi 11.30; Ymir 11.922; Hyrrokkin 12.76; Greip 12.79*; Ijiraq 13.03; Albiorix 13.32; Bestla 14.624; Bebhionn 16.40; Paaliaq 18.75; Kiviuq 21.96; Erriapus 28.15; Thrymr 35 or >45* Tarqeq 76.8.More recent data strengthen the notion that objects in orbits with an inclination supplemental angle i' > 27° have significantly slower spin rates than those at i' 27°, Siarnaq, stands opposed to at least eight objects with faster spins and i' 27° bin contains all nine known prograde moons and four retrograde objects.A total of 25 out of 38 known outer moons has been observed with Cassini, and there is no chance to observe the 13 missing objects until end-of-mission. However, all unobserved objects are part of the i' 27° are known, and none of them is a fast rotator, with no exception.Several objects were observed repeatedly to determine pole directions, sidereal periods, and convex shapes. A few lightcurves have been observed to show three maxima and three minima even at low phase angles, suggesting objects with a triangular equatorial cross-section. Some objects with 2 maxima/ 2 minima are probably quite elongated. One moon even shows lightcurves with 4 maxima/ 4 minima.

  14. THE MEASUREMENT METHODOLOGY IMPROVEMENT OF THE HORIZONTAL IRREGULARITIES IN PLAN

    Directory of Open Access Journals (Sweden)

    O. M. Patlasov

    2015-08-01

    Full Text Available Purpose. Across the track superstructure (TSS there are structures where standard approach to the decision on the future of their operation is not entirely correct or acceptable. In particular, it concerns the track sections which are sufficiently quickly change their geometric parameters: the radius of curvature, angle of rotation, and the like. As an example, such portions of TSS may include crossovers where their component is within the so-called connecting part, which at a sufficiently short length, substantially changes curvature. The estimation of the position in terms of a design on the basis of the existing technique (by the difference in the adjacent arrows bending is virtually impossible. Therefore it is proposed to complement and improve the methodology for assessing the situation of the curve in plan upon difference in the adjacent versine. Methodology. The possible options for measuring horizontal curves in the plan were analyzed. The most adequate method, which does not contradict existing on the criterion of the possibility of using established standards was determined. The ease of measurement and calculation was took into account. Findings. Qualitative and quantitative verification of the proposed and existing methods showed very good agreement of the measurement results. This gives grounds to assert that this methodology can be recommended to the workers of track facilities in the assessment of horizontal irregularities in plan not only curves, but also within the connecting part of switch congresses. Originality. The existing method of valuation of the geometric position of the curves in the plan was improved. It does not create new regulations, and all results are evaluated by existing norms. Practical value. The proposed technique makes it possible, without creating a new regulatory framework, to be attached to existing one, and expanding the boundaries of its application. This method can be used not only for ordinary curves

  15. Contribution of tropical instability waves to ENSO irregularity

    Science.gov (United States)

    Holmes, Ryan M.; McGregor, Shayne; Santoso, Agus; England, Matthew H.

    2018-05-01

    Tropical instability waves (TIWs) are a major source of internally-generated oceanic variability in the equatorial Pacific Ocean. These non-linear phenomena play an important role in the sea surface temperature (SST) budget in a region critical for low-frequency modes of variability such as the El Niño-Southern Oscillation (ENSO). However, the direct contribution of TIW-driven stochastic variability to ENSO has received little attention. Here, we investigate the influence of TIWs on ENSO using a 1/4° ocean model coupled to a simple atmosphere. The use of a simple atmosphere removes complex intrinsic atmospheric variability while allowing the dominant mode of air-sea coupling to be represented as a statistical relationship between SST and wind stress anomalies. Using this hybrid coupled model, we perform a suite of coupled ensemble forecast experiments initiated with wind bursts in the western Pacific, where individual ensemble members differ only due to internal oceanic variability. We find that TIWs can induce a spread in the forecast amplitude of the Niño 3 SST anomaly 6-months after a given sequence of WWBs of approximately ± 45% the size of the ensemble mean anomaly. Further, when various estimates of stochastic atmospheric forcing are added, oceanic internal variability is found to contribute between about 20% and 70% of the ensemble forecast spread, with the remainder attributable to the atmospheric variability. While the oceanic contribution to ENSO stochastic forcing requires further quantification beyond the idealized approach used here, our results nevertheless suggest that TIWs may impact ENSO irregularity and predictability. This has implications for ENSO representation in low-resolution coupled models.

  16. METAL ABUNDANCES OF 12 DWARF IRREGULARS FROM THE ADBS SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Haurberg, Nathalie C.; Salzer, John J. [Department of Astronomy, Indiana University, 727 E. Third St., Bloomington, IN 47405 (United States); Rosenberg, Jessica, E-mail: nhaurber@astro.indiana.edu, E-mail: slaz@astro.indiana.edu, E-mail: jrosenb4@gmu.edu [School of Physics, Astronomy and Computational Science, George Mason University, MS 3F3, Fairfax, VA 22030 (United States)

    2013-03-01

    We have analyzed long-slit spectra of 12 dwarf irregular galaxies from the Arecibo Dual Beam Survey (ADBS). These galaxies represent a heterogeneous sample of objects detected by ADBS, but on average are relatively gas-rich, low-surface-brightness, and low-mass, thus represent a region of the galaxian population that is not commonly included in optical surveys. The metallicity-luminosity relationship for these galaxies is analyzed; the galaxies discussed in this paper appear to be under-abundant at a given luminosity when compared to a sample from the literature. We attempt to identify a 'second parameter' responsible for the intrinsic scatter and apparent under-abundance of our galaxies. We do not find a definitive second parameter but note the possible indication that infall or mixing of pristine gas may be responsible. We derive oxygen abundances for multiple H II regions in many of our galaxies but do not find any strong indications of metallicity variation within the galaxies except in one case where we see variation between an isolated H II region and the rest of the galaxy. Our data set includes the galaxy with the largest known H I-to-optical size ratio, ADBS 113845+2008. Our abundance analysis of this galaxy reveals that it is strongly over-enriched compared to galaxies of similar luminosity, indicating it is not a young object and confirming the result from Cannon et al. that this galaxy appears to be intrinsically rare in the local universe.

  17. Low Bone Density

    Science.gov (United States)

    ... Density Exam/Testing › Low Bone Density Low Bone Density Low bone density is when your bone density ... people with normal bone density. Detecting Low Bone Density A bone density test will determine whether you ...

  18. The Westerbork HI Survey of Irregular and Spiral Galaxies, WHISP

    NARCIS (Netherlands)

    van der Hulst, JM; van Albada, TS; Sancisi, R; Hibbard, JE; Rupen, MP; VanGorkom, JH

    2001-01-01

    This paper briefly describes WHISP, an ongoing project to image the H(I) in a large sample of nearby galaxies with the Westerbork Synthesis Radio Telescope (WSRT). The goal of the survey is to investigate the H(I) density distributions and velocity fields of galaxies as a function of Hubble type,

  19. The Westerbork HI survey of irregular and spiral galaxies, WHISP

    NARCIS (Netherlands)

    van der Hulst, JM; Taylor, AR; Landecker, TL; Willis, AG

    2002-01-01

    This paper briefly describes WHISP, an ongoing project to image the HI in a large sample of nearby galaxies with the Westerbork Synthesis Radio Telescope (WSRT). The goal of the survey is to investigate the HI density distributions and velocity fields of galaxies as a function of Hubble type,

  20. The Plasma Environment Associated With Equatorial Ionospheric Irregularities

    Science.gov (United States)

    Smith, Jonathon M.; Heelis, R. A.

    2018-02-01

    We examine the density structure of equatorial depletions referred to here as equatorial plasma bubbles (EPBs). Data recorded by the Ion Velocity Meter as part of the Coupled Ion Neutral Dynamics Investigation (CINDI) aboard the Communication/Navigation Outage Forecasting System (C/NOFS) satellite are used to study EPBs from 1600 to 0600 h local time at altitudes from 350 to 850 km. The data are taken during the 7 years from 2008 to 2014, more than one half of a magnetic solar cycle, that include solar minimum and a moderate solar maximum. Using a rolling ball algorithm, EPBs are identified by profiles in the plasma density, each having a depth measured as the percent change between the background and minimum density (ΔN/N). During solar moderate activity bubbles observed in the topside postsunset sector are more likely to have large depths compared to those observed in the topside postmidnight sector. Large bubble depths can be observed near 350 km in the bottomside F region in the postsunset period. Conversely at solar minimum the distribution of depths is similar in the postsunset and postmidnight sectors in all longitude sectors. Deep bubbles are rarely observed in the topside postsunset sector and never in the bottomside above 400 km in altitude. We suggest that these features result from the vertical drift of the plasma for these two solar activity levels. These drift conditions affect both the background density in which bubbles are embedded and the growth rate of perturbations in the bottomside where bubbles originate.

  1. Proper Elements and Secular Resonances for Irregular Satellites

    Science.gov (United States)

    Beaugé, C.; Nesvorný, D.

    2007-06-01

    We present results of an analytical study of proper elements and secular resonances for the irregular satellites of the outer planets. In the case of the Jovian system we identify three satellite families, two of them previously known (Carme and Ananke), plus a new agglomeration of four bodies that includes Pasiphae as its largest member. While the distribution of proper elements for Saturn's moons seems to be more random, a small cluster was found for the direct moons formed by Albiorix, Erriapo, and 2004 S1, slightly different from the so-called Gaulish cluster. No significant families are detected in the present study for the Uranian or Neptunian satellite systems. For each satellite system we determine the location of several secular resonances in the proper element space. Apart from the well-known resonance locks of Pasiphae, Sinope, and Siarnaq, a comparison between the resonance locations and proper elements shows that Saturn's satellite Narvi also exhibits temporary librations in the ϖ-ϖsolar resonance. However, unlike the resonant Jovian moons that are located in the same configuration, Narvi's critical argument librates alternately around values near 90° and 270°. Neither the Uranian nor Neptunian systems seem to have resonant moons. The resonant dynamics of the real satellites in the vicinity of ϖ˙-ϖ˙solar=0 is studied with a simple model for secular resonances based on the restricted three-body problem. Depending on the initial conditions, we show the existence of one or two modes of libration that can occur at different values of the critical angle, showing a good correspondence with the observed behavior of all the resonant moons. Finally, we discuss the global distribution of the real satellites with respect to the secular resonances, as compared with synthetic populations of bodies drawn solely from stability conditions. For Saturn, we find that the present satellite population appears compatible with simple random distributions. Although

  2. The dynamics of rings around small, irregular bodies

    Science.gov (United States)

    Sicardy, Bruno

    2017-06-01

    Stellar occultations revealed the presence of two dense rings around the Centaur object (10199) Chariklo (Braga-Ribas et al., Nature 508, 72, 2014). This is the first ring system discovered around an object that is not a giant planet, suggesting that rings may exist around numerous bodies in the solar system. Chariklo's rings roughly reside at the outer limit of the Roche zone of the body. Moreover, the main ring has sharp edges, which call for the presence of putative shepherd satellites. Those characteristics give an image of Chariklo's rings that are rather similar, in terms of dynamics, to those surrounding the gaseous planets.An important difference exists, however, between giant planets and small bodies: the formers are highly axisymmetric, while the latters can support mass anomalies (eg surface topographic features) or non-spherical shapes (eg an ellipsoidal figure of equilibrium) that involve masses, relative to the body itself, as large as 10-4-10-3.We investigate the effect of non-axisymmetric terms in the potential of the body upon a collisional debris disk that initially surrounds a small irregular body. We show that the corotation points being maxima of energy, dissipative collisions remove the particles from the corotation zone over short time scales (< 106 years). Moreover, the Lindblad resonances inside the corotation radius create torques that drive the particles onto the surface of the central body. Conversely, the outer Lindblad resonances push the disk material beyond the outer 3/2 and 2/1 Lindblad resonances.Taking as an example Chariklo's ring system, for which recent data have been obtained from stellar occultations, we show that the Lindblad resonant torques actuate over short time scales (< 106 years). This general picture offers a natural explanation of the presence of dense rings at the outer limit of Chariklo's Roche zone, and their absence closer to the body.The work leading to this results has received funding from the European

  3. Dynamic stability of passive dynamic walking on an irregular surface.

    Science.gov (United States)

    Su, Jimmy Li-Shin; Dingwell, Jonathan B

    2007-12-01

    Falls that occur during walking are a significant health problem. One of the greatest impediments to solve this problem is that there is no single obviously "correct" way to quantify walking stability. While many people use variability as a proxy for stability, measures of variability do not quantify how the locomotor system responds to perturbations. The purpose of this study was to determine how changes in walking surface variability affect changes in both locomotor variability and stability. We modified an irreducibly simple model of walking to apply random perturbations that simulated walking over an irregular surface. Because the model's global basin of attraction remained fixed, increasing the amplitude of the applied perturbations directly increased the risk of falling in the model. We generated ten simulations of 300 consecutive strides of walking at each of six perturbation amplitudes ranging from zero (i.e., a smooth continuous surface) up to the maximum level the model could tolerate without falling over. Orbital stability defines how a system responds to small (i.e., "local") perturbations from one cycle to the next and was quantified by calculating the maximum Floquet multipliers for the model. Local stability defines how a system responds to similar perturbations in real time and was quantified by calculating short-term and long-term local exponential rates of divergence for the model. As perturbation amplitudes increased, no changes were seen in orbital stability (r(2)=2.43%; p=0.280) or long-term local instability (r(2)=1.0%; p=0.441). These measures essentially reflected the fact that the model never actually "fell" during any of our simulations. Conversely, the variability of the walker's kinematics increased exponentially (r(2)>or=99.6%; psimulated conditions, the walker remained orbitally stable, while exhibiting substantial local instability. This was because very small initial perturbations diverged away from the limit cycle, while larger

  4. X-ray pulsars in nearby irregular galaxies

    Science.gov (United States)

    Yang, Jun

    2018-01-01

    The Small Magellanic Cloud (SMC), Large Magellanic Cloud (LMC) and Irregular Galaxy IC 10 are valuable laboratories to study the physical, temporal and statistical properties of the X-ray pulsar population with multi-satellite observations, in order to probe fundamental physics. The known distance of these galaxies can help us easily categorize the luminosity of the pulsars and their age difference can be helpful for for studying the origin and evolution of compact objects. Therefore, a complete archive of 116 XMM-Newton PN, 151 Chandra (Advanced CCD Imaging Spectrometer) ACIS, and 952 RXTE PCA observations for the pulsars in the Small Magellanic Cloud (SMC) were collected and analyzed, along with 42 XMM-Newton and 30 Chandra observations for the Large Magellanic Cloud, spanning 1997-2014. From a sample of 67 SMC pulsars we generate a suite of products for each pulsar detection: spin period, flux, event list, high time-resolution light-curve, pulse-profile, periodogram, and X-ray spectrum. Combining all three satellites, I generated complete histories of the spin periods, pulse amplitudes, pulsed fractions and X-ray luminosities. Many of the pulsars show variations in pulse period due to the combination of orbital motion and accretion torques. Long-term spin-up/down trends are seen in 28/25 pulsars respectively, pointing to sustained transfer of mass and angular momentum to the neutron star on decadal timescales. The distributions of pulse detection and flux as functions of spin period provide interesting findings: mapping boundaries of accretion-driven X-ray luminosity, and showing that fast pulsars (P<10 s) are rarely detected, which yet are more prone to giant outbursts. In parallel we compare the observed pulse profiles to our general relativity (GR) model of X-ray emission in order to constrain the physical parameters of the pulsars.In addition, we conduct a search for optical counterparts to X-ray sources in the local dwarf galaxy IC 10 to form a comparison

  5. Shape of the nuclear magnetic resonance line in anisotropic superconductors with an irregular vortex lattice

    International Nuclear Information System (INIS)

    Minkin, A.V.; Tsarevskij, S.L.

    2006-01-01

    For high-temperature superconductors the shape of a NMR spectrum line is built regarding for variation of inhomogeneity of irregular vortex lattice magnetic field near superconductor surface. It is shown that the shape of a NMR line is not simply widened but noticeably varies depending on the degree of irregularity of a superconductor vortex lattice. This variation is associated with a local symmetry decrease in an irregular vortex lattice of the superconductor. Taking into account these circumstances may considerably change conclusions about the type of a vortex lattice and superconductor parameters which are commonly gained from NMR line shape analysis [ru

  6. Randomness control of vehicular motion through a sequence of traffic signals at irregular intervals

    International Nuclear Information System (INIS)

    Nagatani, Takashi

    2010-01-01

    We study the regularization of irregular motion of a vehicle moving through the sequence of traffic signals with a disordered configuration. Each traffic signal is controlled by both cycle time and phase shift. The cycle time is the same for all signals, while the phase shift varies from signal to signal by synchronizing with intervals between a signal and the next signal. The nonlinear dynamic model of the vehicular motion is presented by the stochastic nonlinear map. The vehicle exhibits the very complex behavior with varying both cycle time and strength of irregular intervals. The irregular motion induced by the disordered configuration is regularized by adjusting the phase shift within the regularization regions.

  7. Target Tracking of a Linear Time Invariant System under Irregular Sampling

    Directory of Open Access Journals (Sweden)

    Jin Xue-Bo

    2012-11-01

    Full Text Available Due to event-triggered sampling in a system, or maybe with the aim of reducing data storage, tracking many applications will encounter irregular sampling time. By calculating the matrix exponential using an inverse Laplace transform, this paper transforms the irregular sampling tracking problem to the problem of tracking with time-varying parameters of a system. Using the common Kalman filter, the developed method is used to track a target for the simulated trajectory and video tracking. The results of simulation experiments have shown that it can obtain good estimation performance even at a very high irregular rate of measurement sampling time.

  8. Level densities

    International Nuclear Information System (INIS)

    Ignatyuk, A.V.

    1998-01-01

    For any applications of the statistical theory of nuclear reactions it is very important to obtain the parameters of the level density description from the reliable experimental data. The cumulative numbers of low-lying levels and the average spacings between neutron resonances are usually used as such data. The level density parameters fitted to such data are compiled in the RIPL Starter File for the tree models most frequently used in practical calculations: i) For the Gilber-Cameron model the parameters of the Beijing group, based on a rather recent compilations of the neutron resonance and low-lying level densities and included into the beijing-gc.dat file, are chosen as recommended. As alternative versions the parameters provided by other groups are given into the files: jaeri-gc.dat, bombay-gc.dat, obninsk-gc.dat. Additionally the iljinov-gc.dat, and mengoni-gc.dat files include sets of the level density parameters that take into account the damping of shell effects at high energies. ii) For the backed-shifted Fermi gas model the beijing-bs.dat file is selected as the recommended one. Alternative parameters of the Obninsk group are given in the obninsk-bs.dat file and those of Bombay in bombay-bs.dat. iii) For the generalized superfluid model the Obninsk group parameters included into the obninsk-bcs.dat file are chosen as recommended ones and the beijing-bcs.dat file is included as an alternative set of parameters. iv) For the microscopic approach to the level densities the files are: obninsk-micro.for -FORTRAN 77 source for the microscopical statistical level density code developed in Obninsk by Ignatyuk and coworkers, moller-levels.gz - Moeller single-particle level and ground state deformation data base, moller-levels.for -retrieval code for Moeller single-particle level scheme. (author)

  9. Density gradients in the solar plasma observed by interplanetary scintillation

    International Nuclear Information System (INIS)

    Gapper, G.R.; Hewish, A.

    1981-01-01

    A new technique is described which overcomes the limitation set by Fresnel filtering in previous IPS studies of the small-scale density irregularities in the solar plasma. Phase gradients introduced by irregularities larger than the Fresnel limit cause transverse displacements of the small-scale scintillation pattern. In the presence of the solar wind, such refraction effects may be revealed by simultaneous measurements of intensity scintillation at two radio frequencies. Observations show that the structure corresponding to temporal frequencies approximately 0.02 Hz is in agreement with an extrapolation of the Kolmogorov spectrum derived from spacecraft data at lower frequencies. (author)

  10. Accuracy of methods for detecting an irregular pulse and suspected atrial fibrillation: A systematic review and meta-analysis.

    Science.gov (United States)

    Taggar, Jaspal S; Coleman, Tim; Lewis, Sarah; Heneghan, Carl; Jones, Matthew

    2016-08-01

    Pulse palpation has been recommended as the first step of screening to detect atrial fibrillation. We aimed to determine and compare the accuracy of different methods for detecting pulse irregularities caused by atrial fibrillation. We systematically searched MEDLINE, EMBASE, CINAHL and LILACS until 16 March 2015. Two reviewers identified eligible studies, extracted data and appraised quality using the QUADAS-2 instrument. Meta-analysis, using the bivariate hierarchical random effects method, determined average operating points for sensitivities, specificities, positive and negative likelihood ratios (PLR, NLR); we constructed summary receiver operating characteristic plots. Twenty-one studies investigated 39 interventions (n = 15,129 pulse assessments) for detecting atrial fibrillation. Compared to 12-lead electrocardiography (ECG) diagnosed atrial fibrillation, blood pressure monitors (BPMs; seven interventions) and non-12-lead ECGs (20 interventions) had the greatest accuracy for detecting pulse irregularities attributable to atrial fibrillation (BPM: sensitivity 0.98 (95% confidence interval (CI) 0.92-1.00), specificity 0.92 (95% CI 0.88-0.95), PLR 12.1 (95% CI 8.2-17.8) and NLR 0.02 (95% CI 0.00-0.09); non-12-lead ECG: sensitivity 0.91 (95% CI 0.86-0.94), specificity 0.95 (95% CI 0.92-0.97), PLR 20.1 (95% CI 12-33.7), NLR 0.09 (95% CI 0.06-0.14)). There were similar findings for smartphone applications (six interventions) although these studies were small in size. The sensitivity and specificity of pulse palpation (six interventions) were 0.92 (95% CI 0.85-0.96) and 0.82 (95% CI 0.76-0.88), respectively (PLR 5.2 (95% CI 3.8-7.2), NLR 0.1 (95% CI 0.05-0.18)). BPMs and non-12-lead ECG were most accurate for detecting pulse irregularities caused by atrial fibrillation; other technologies may therefore be pragmatic alternatives to pulse palpation for the first step of atrial fibrillation screening. © The European Society of Cardiology 2015.

  11. Spelling pronunciation and visual preview both facilitate learning to spell irregular word

    NARCIS (Netherlands)

    Hilte, M.; Reitsma, P.

    2006-01-01

    Spelling pronunciations are hypothesized to be helpful in building up relatively stable phonologically underpinned orthographic representations, particularly for learning words with irregular phoneme-grapheme correspondences. In a four-week computer-based training, the efficacy of spelling

  12. On Impulsive Boundary Value Problems of Fractional Differential Equations with Irregular Boundary Conditions

    Directory of Open Access Journals (Sweden)

    Guotao Wang

    2012-01-01

    Full Text Available We study nonlinear impulsive differential equations of fractional order with irregular boundary conditions. Some existence and uniqueness results are obtained by applying standard fixed-point theorems. For illustration of the results, some examples are discussed.

  13. Inter-hospital Cross-validation of Irregular Discharge Patterns for Young vs. Old Psychiatric Patients

    Science.gov (United States)

    Mozdzierz, Gerald J.; Davis, William E.

    1975-01-01

    Type of discharge (irregular vs. regular) and length of time hospitalized were used as unobtrusive measures of psychiatric patient acceptance of hospital treatment regime among two groups (18-27 years and 45 years and above) of patients. (Author)

  14. Irregular singularities in Liouville theory and Argyres-Douglas type gauge theories, I

    Energy Technology Data Exchange (ETDEWEB)

    Gaiotto, D. [Institute for Advanced Study (IAS), Princeton, NJ (United States); Teschner, J. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2012-03-15

    Motivated by problems arising in the study of N=2 supersymmetric gauge theories we introduce and study irregular singularities in two-dimensional conformal field theory, here Liouville theory. Irregular singularities are associated to representations of the Virasoro algebra in which a subset of the annihilation part of the algebra act diagonally. In this paper we define natural bases for the space of conformal blocks in the presence of irregular singularities, describe how to calculate their series expansions, and how such conformal blocks can be constructed by some delicate limiting procedure from ordinary conformal blocks. This leads us to a proposal for the structure functions appearing in the decomposition of physical correlation functions with irregular singularities into conformal blocks. Taken together, we get a precise prediction for the partition functions of some Argyres-Douglas type theories on S{sup 4}. (orig.)

  15. Conflict management among irregular immigrants: the micro politics of intercultural respect.

    OpenAIRE

    Clough, Paul; Works in Progress Seminars Series

    2010-01-01

    A talk in the Works in Progress Seminars Series with the title of "Conflict management among irregular immigrants: the micro politics of intercultural respect". This talk is given by Prof Paul Clough.

  16. Irregular singularities in Liouville theory and Argyres-Douglas type gauge theories, I

    International Nuclear Information System (INIS)

    Gaiotto, D.; Teschner, J.

    2012-03-01

    Motivated by problems arising in the study of N=2 supersymmetric gauge theories we introduce and study irregular singularities in two-dimensional conformal field theory, here Liouville theory. Irregular singularities are associated to representations of the Virasoro algebra in which a subset of the annihilation part of the algebra act diagonally. In this paper we define natural bases for the space of conformal blocks in the presence of irregular singularities, describe how to calculate their series expansions, and how such conformal blocks can be constructed by some delicate limiting procedure from ordinary conformal blocks. This leads us to a proposal for the structure functions appearing in the decomposition of physical correlation functions with irregular singularities into conformal blocks. Taken together, we get a precise prediction for the partition functions of some Argyres-Douglas type theories on S 4 . (orig.)

  17. Effect of surface stress and irregularity of the interface on the ...

    Indian Academy of Sciences (India)

    Surface stress; irregularity of the interface; magneto-elastic crustal ... stress plays a vital role in the propagation of waves due to the fact that the surface of a ...... Mumbai, for his computational help towards the numerical calculations and graphs.

  18. Density and shape factor of sodium aerosol. Progress report, January 1, 1976--March 31, 1976

    International Nuclear Information System (INIS)

    Hinds, W.; First, M.W.

    1976-05-01

    Several approaches for characterizing the physical and aerodynamic properties of irregularly shaped aerosol particles are reviewed. Measurements of density modification factor, dynamic shape factor, and particle density using an aerosol centrifuge and a scanning electron microscope are described. Calibration procedures for this characterization method are described and preliminary results reported

  19. Efficient irregular wavefront propagation algorithms on Intel® Xeon Phi™

    OpenAIRE

    Gomes, Jeremias M.; Teodoro, George; de Melo, Alba; Kong, Jun; Kurc, Tahsin; Saltz, Joel H.

    2015-01-01

    We investigate the execution of the Irregular Wavefront Propagation Pattern (IWPP), a fundamental computing structure used in several image analysis operations, on the Intel® Xeon Phi™ co-processor. An efficient implementation of IWPP on the Xeon Phi is a challenging problem because of IWPP’s irregularity and the use of atomic instructions in the original IWPP algorithm to resolve race conditions. On the Xeon Phi, the use of SIMD and vectorization instructions is critical to attain high perfo...

  20. SUB-SAHARAN IRREGULAR MIGRANTS IN MOROCCO & THE EXCEPTIONAL REGULARISATION PROGRAMME IN 2014

    OpenAIRE

    Naama, Mbarek

    2017-01-01

    Naama, Mbarek. Sub-Saharan Irregular Migrants in Morocco and the Exceptional Regularisation Programme in 2014. Diak South Helsinki Finland. Spring 2017. 43 Pages. Language: English. Diaconia University of Applied Sciences, Degree Programme in Social Services, Option in Community Development, Bachelor of Social Services (UAS). After decades of ignoring irregular migration and refusing to acknowledge that Morocco is no longer just a transit but also a host country for increasing complex mig...

  1. Modalities of Tonometry and their Accuracy with Respect to Corneal Thickness and Irregularities

    OpenAIRE

    Carlos Gustavo V. De Moraes; Tiago S. Prata; Jeffrey Liebmann; Robert Ritch

    2008-01-01

    Recent advances in tonometry have led to the development of a number of devices with differing clinical applications. Their role in cases of abnormal corneal thickness and surface irregularities is particularly important, as inaccurate estimation of the true intraocular pressure (IOP) in such cases may lead to suboptimal evaluation. The purpose of the present review was to evaluate the accuracy of the most widely used devices in cases of corneal thickness and surface irregularities, based ...

  2. A Generalized FDM for solving the Poisson's Equation on 3D Irregular Domains

    Directory of Open Access Journals (Sweden)

    J. Izadian

    2014-01-01

    Full Text Available In this paper a new method for solving the Poisson's equation with Dirichlet conditions on irregular domains is presented. For this purpose a generalized finite differences method is applied for numerical differentiation on irregular meshes. Three examples on cylindrical and spherical domains are considered. The numerical results are compared with analytical solution. These results show the performance and efficiency of the proposed method.

  3. Some recent efforts toward high density implosions

    International Nuclear Information System (INIS)

    McClellan, G.E.

    1980-01-01

    Some recent Livermore efforts towards achieving high-density implosions are presented. The implosion dynamics necessary to compress DT fuel to 10 to 100 times liquid density are discussed. Methods of diagnosing the maximum DT density for a specific design are presented along with results to date. The dynamics of the double-shelled target with an exploding outer shell are described, and some preliminary experimental results are presented

  4. Diagnosing Diabetes and Learning about Prediabetes

    Science.gov (United States)

    ... Listen En Español Diagnosing Diabetes and Learning About Prediabetes There are several ways to diagnose diabetes. Each ... or equal to 200 mg/dl What is Prediabetes? Before people develop type 2 diabetes, they almost ...

  5. A simulation study of impulsive penetration of solar wind irregularities into the magnetosphere at the dayside magnetopause

    International Nuclear Information System (INIS)

    Ma, Z.W.; Hawkins, J.G.; Lee, L.C.

    1991-01-01

    A two-dimensional magnetohydrodynamic code is used to study impulsive penetration processes that occur when a plasma irregularity in the magnetosheath, modeled as a field-aligned filament, impinges on the dayside magnetopause. If the magnetic fields in the magnetosheath and magnetosphere are parallel or antiparallel, then a filament in the magnetosheath can always penetrate into the magnetosphere. However, if the fields in the magnetosheath and magnetosphere are not aligned, then a filament can only penetrate into the magnetosphere when its initial kinetic energy density exceeds the magnetic energy density attributed to the transverse component of the magnetic field by a factor of 50. In this case, the magnetospheric field lines reconnect behind the filament, thereby trapping it within the magnetosphere. Otherwise, the increasing magnetic stress in front of the filament will eventually stop the filament from further penetration. For typical parameters found at the dayside magnetopause, the threshold condition obtained from this two-dimensional model predicts that penetration is possible only when the angle between the fields is within approximately 5 of parallel or antiparallel. During the penetration process, velocity vortices are observed both inside the filament and in the external plasma. Either increased β within the magnetosphere, or the larger plasma density at the magnetopause associated with antiparallel magnetic fields, will act to reduce the penetration velocity

  6. Characterizing neural activities evoked by manual acupuncture through spiking irregularity measures

    International Nuclear Information System (INIS)

    Xue Ming; Wang Jiang; Deng Bin; Wei Xi-Le; Yu Hai-Tao; Chen Ying-Yuan

    2013-01-01

    The neural system characterizes information in external stimulations by different spiking patterns. In order to examine how neural spiking patterns are related to acupuncture manipulations, experiments are designed in such a way that different types of manual acupuncture (MA) manipulations are taken at the ‘Zusanli’ point of experimental rats, and the induced electrical signals in the spinal dorsal root ganglion are detected and recorded. The interspike interval (ISI) statistical histogram is fitted by the gamma distribution, which has two parameters: one is the time-dependent firing rate and the other is a shape parameter characterizing the spiking irregularities. The shape parameter is the measure of spiking irregularities and can be used to identify the type of MA manipulations. The coefficient of variation is mostly used to measure the spike time irregularity, but it overestimates the irregularity in the case of pronounced firing rate changes. However, experiments show that each acupuncture manipulation will lead to changes in the firing rate. So we combine four relatively rate-independent measures to study the irregularity of spike trains evoked by different types of MA manipulations. Results suggest that the MA manipulations possess unique spiking statistics and characteristics and can be distinguished according to the spiking irregularity measures. These studies have offered new insights into the coding processes and information transfer of acupuncture. (interdisciplinary physics and related areas of science and technology)

  7. Effects of surface irregularities on intensity data from laser scanning: an experimental approach.

    Directory of Open Access Journals (Sweden)

    G. Teza

    2008-06-01

    Full Text Available The results of an experiment carried out with the aim to investigate the role of surface irregularities on the intensity data provided by a terrestrial laser scanner (TLS survey are reported here. Depending on surface roughness, the interaction between an electromagnetic wave and microscopic irregularities leads to a Lambertian-like diffusive light reflection, allowing the TLS to receive the backscattered component of the signal. The described experiment consists in a series of TLS-based acquisitions of a rotating artificial target specifically conceived in order to highlight the effects on the intensity data due to surface irregularity. This target is articulated in a flat plate and in an irregular surface, whose macro-roughness has a characteristic length with the same order of the spot size. Results point out the different behavior of the plates. The intensity of the signal backscattered by the planar element decreases if the incidence angle increases, whereas the intensity of the signal backscattered by the irregular surface is almost constant if the incidence angle varies. Since the typical surfaces acquired in a geological/geophysical survey are generally irregular, these results imply that the intensity data can be easily used in order to evaluate the reflectance of the material at the considered wavelength, e.g. for pattern recognition purposes.

  8. Radar Observations of 8.3-m scale equatorial spread F irregularities over Trivandrum

    Directory of Open Access Journals (Sweden)

    D. Tiwari

    2004-03-01

    Full Text Available In this paper, we present observations of equatorial spread F (ESF irregularities made using a newly installed 18MHz radar located at Trivandrum. We characterize the morphology and the spectral parameters of the 8.3-m ESF irregularities which are found to be remarkably different from that observed so extensively at the 3-m scale size. We also present statistical results of the irregularities in the form of percentage occurrence of the echoes and spectral parameters (SNR, Doppler velocity, Spectral width. The Doppler spectra are narrower, less structured and less variable in time as compared to those observed for 3-m scale size. We have never observed the ESF irregularity velocities to be supersonic here unlike those at Jicamarca, and the velocities are found to be within ±200ms–1. The spectral widths are found to be less than 150ms–1. Hence, the velocities and spectral width both are smaller than those reported for 3-m scale size. The velocities and spectral widths are further found to be much smaller than those of the American sector. These observations are compared with those reported elsewhere and discussed in the light of present understanding on the ESF irregularities at different wavelengths.

    Key words. Ionoshphere (equatorial ionosphere, plasma waves and instabilities; ionospheric irregularities

  9. Radar Observations of 8.3-m scale equatorial spread F irregularities over Trivandrum

    Directory of Open Access Journals (Sweden)

    D. Tiwari

    2004-03-01

    Full Text Available In this paper, we present observations of equatorial spread F (ESF irregularities made using a newly installed 18MHz radar located at Trivandrum. We characterize the morphology and the spectral parameters of the 8.3-m ESF irregularities which are found to be remarkably different from that observed so extensively at the 3-m scale size. We also present statistical results of the irregularities in the form of percentage occurrence of the echoes and spectral parameters (SNR, Doppler velocity, Spectral width. The Doppler spectra are narrower, less structured and less variable in time as compared to those observed for 3-m scale size. We have never observed the ESF irregularity velocities to be supersonic here unlike those at Jicamarca, and the velocities are found to be within ±200ms–1. The spectral widths are found to be less than 150ms–1. Hence, the velocities and spectral width both are smaller than those reported for 3-m scale size. The velocities and spectral widths are further found to be much smaller than those of the American sector. These observations are compared with those reported elsewhere and discussed in the light of present understanding on the ESF irregularities at different wavelengths. Key words. Ionoshphere (equatorial ionosphere, plasma waves and instabilities; ionospheric irregularities

  10. New prospective 4D-CT for mitigating the effects of irregular respiratory motion

    Science.gov (United States)

    Pan, Tinsu; Martin, Rachael M.; Luo, Dershan

    2017-08-01

    Artifact caused by irregular respiration is a major source of error in 4D-CT imaging. We propose a new prospective 4D-CT to mitigate this source of error without new hardware, software or off-line data-processing on the GE CT scanner. We utilize the cine CT scan in the design of the new prospective 4D-CT. The cine CT scan at each position can be stopped by the operator when an irregular respiration occurs, and resumed when the respiration becomes regular. This process can be repeated at one or multiple scan positions. After the scan, a retrospective reconstruction is initiated on the CT console to reconstruct only the images corresponding to the regular respiratory cycles. The end result is a 4D-CT free of irregular respiration. To prove feasibility, we conducted a phantom and six patient studies. The artifacts associated with the irregular respiratory cycles could be removed from both the phantom and patient studies. A new prospective 4D-CT scanning and processing technique to mitigate the impact of irregular respiration in 4D-CT has been demonstrated. This technique can save radiation dose because the repeat scans are only at the scan positions where an irregular respiration occurs. Current practice is to repeat the scans at all positions. There is no cost to apply this technique because it is applicable on the GE CT scanner without new hardware, software or off-line data-processing.

  11. Influence of long-wavelength track irregularities on the motion of a high-speed train

    Science.gov (United States)

    Hung, C. F.; Hsu, W. L.

    2018-01-01

    Vertical track irregularities over viaducts in high-speed rail systems could be possibly caused by concrete creep if pre-stressed concrete bridges are used. For bridge spans that are almost uniformly distributed, track irregularity exhibits a near-regular wave profile that excites car bodies as a high-speed train moves over the bridge system. A long-wavelength irregularity induces low-frequency excitation that may be close to the natural frequencies of the train suspension system, thereby causing significant vibration of the car body. This paper investigates the relationship between the levels of car vibration, bridge vibration, track irregularity, and the train speed. First, this study investigates the vibration levels of a high-speed train and bridge system using 3D finite-element (FE) transient dynamic analysis, before and after adjustment of vertical track irregularities by means of installing shimming plates under rail pads. The analysis models are validated by in situ measurements and on-board measurement. Parametric studies of car body vibration and bridge vibration under three different levels of track irregularity at five train speeds and over two bridge span lengths are conducted using the FE model. Finally, a discontinuous shimming pattern is proposed to avoid vehicle suspension resonance.

  12. Properties of the Irregular Satellite System around Uranus Inferred from K2 , Herschel , and Spitzer Observations

    Energy Technology Data Exchange (ETDEWEB)

    Farkas-Takács, A.; Kiss, Cs.; Pál, A.; Molnár, L.; Szabó, Gy. M.; Hanyecz, O.; Sárneczky, K.; Szabó, R.; Marton, G.; Szakáts, R.; Kiss, L. L. [Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, Konkoly Thege Miklós út 15-17, H-1121 Budapest (Hungary); Mommert, M. [Department of Physics and Astronomy, Northern Arizona University, P.O. Box 6010, Flagstaff, AZ 86011 (United States); Müller, T., E-mail: farkas.aniko@csfk.mta.hu [Max-Plank-Institut für extraterrestrsiche Pyhsik, Garching (Germany)

    2017-09-01

    In this paper, we present visible-range light curves of the irregular Uranian satellites Sycorax, Caliban, Prospero, Ferdinand, and Setebos taken with the Kepler Space Telescope over the course of the K2 mission. Thermal emission measurements obtained with the Herschel /PACS and Spitzer /MIPS instruments of Sycorax and Caliban were also analyzed and used to determine size, albedo, and surface characteristics of these bodies. We compare these properties with the rotational and surface characteristics of irregular satellites in other giant planet systems and also with those of main belt and Trojan asteroids and trans-Neptunian objects. Our results indicate that the Uranian irregular satellite system likely went through a more intense collisional evolution than the irregular satellites of Jupiter and Saturn. Surface characteristics of Uranian irregular satellites seem to resemble the Centaurs and trans-Neptunian objects more than irregular satellites around other giant planets, suggesting the existence of a compositional discontinuity in the young solar system inside the orbit of Uranus.

  13. Properties of the Irregular Satellite System around Uranus Inferred from K2, Herschel, and Spitzer Observations

    Science.gov (United States)

    Farkas-Takács, A.; Kiss, Cs.; Pál, A.; Molnár, L.; Szabó, Gy. M.; Hanyecz, O.; Sárneczky, K.; Szabó, R.; Marton, G.; Mommert, M.; Szakáts, R.; Müller, T.; Kiss, L. L.

    2017-09-01

    In this paper, we present visible-range light curves of the irregular Uranian satellites Sycorax, Caliban, Prospero, Ferdinand, and Setebos taken with the Kepler Space Telescope over the course of the K2 mission. Thermal emission measurements obtained with the Herschel/PACS and Spitzer/MIPS instruments of Sycorax and Caliban were also analyzed and used to determine size, albedo, and surface characteristics of these bodies. We compare these properties with the rotational and surface characteristics of irregular satellites in other giant planet systems and also with those of main belt and Trojan asteroids and trans-Neptunian objects. Our results indicate that the Uranian irregular satellite system likely went through a more intense collisional evolution than the irregular satellites of Jupiter and Saturn. Surface characteristics of Uranian irregular satellites seem to resemble the Centaurs and trans-Neptunian objects more than irregular satellites around other giant planets, suggesting the existence of a compositional discontinuity in the young solar system inside the orbit of Uranus.

  14. Modification of transmission dose algorithm for irregularly shaped radiation field and tissue deficit

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Hyong Geon; Shin, Kyo Chul [Dankook Univ., College of Medicine, Seoul (Korea, Republic of); Huh, Soon Nyung; Woo, Hong Gyun; Ha, Sung Whan [Seoul National Univ., College of Medicine, Seoul (Korea, Republic of); Lee, Hyoung Koo [The Catholic Univ., College of Medicine, Seoul (Korea, Republic of)

    2002-07-01

    Algorithm for estimation of transmission dose was modified for use in partially blocked radiation fields and in cases with tissue deficit. The beam data was measured with flat solid phantom in various conditions of beam block. And an algorithm for correction of transmission dose in cases of partially blocked radiation field was developed from the measured data. The algorithm was tested in some clinical settings with irregular shaped field. Also, another algorithm for correction of transmission dose for tissue deficit was developed by physical reasoning. This algorithm was tested in experimental settings with irregular contours mimicking breast cancer patients by using multiple sheets of solid phantoms. The algorithm for correction of beam block could accurately reflect the effect of beam block, with error within {+-}1.0%, both with square fields and irregularly shaped fields. The correction algorithm for tissue deficit could accurately reflect the effect of tissue deficit with errors within {+-}1.0% in most situations and within {+-}3.0% in experimental settings with irregular contours mimicking breast cancer treatment set-up. Developed algorithms could accurately estimate the transmission dose in most radiation treatment settings including irregularly shaped field and irregularly shaped body contour with tissue deficit in transmission dosimetry.

  15. Modification of transmission dose algorithm for irregularly shaped radiation field and tissue deficit

    International Nuclear Information System (INIS)

    Yun, Hyong Geon; Shin, Kyo Chul; Huh, Soon Nyung; Woo, Hong Gyun; Ha, Sung Whan; Lee, Hyoung Koo

    2002-01-01

    Algorithm for estimation of transmission dose was modified for use in partially blocked radiation fields and in cases with tissue deficit. The beam data was measured with flat solid phantom in various conditions of beam block. And an algorithm for correction of transmission dose in cases of partially blocked radiation field was developed from the measured data. The algorithm was tested in some clinical settings with irregular shaped field. Also, another algorithm for correction of transmission dose for tissue deficit was developed by physical reasoning. This algorithm was tested in experimental settings with irregular contours mimicking breast cancer patients by using multiple sheets of solid phantoms. The algorithm for correction of beam block could accurately reflect the effect of beam block, with error within ±1.0%, both with square fields and irregularly shaped fields. The correction algorithm for tissue deficit could accurately reflect the effect of tissue deficit with errors within ±1.0% in most situations and within ±3.0% in experimental settings with irregular contours mimicking breast cancer treatment set-up. Developed algorithms could accurately estimate the transmission dose in most radiation treatment settings including irregularly shaped field and irregularly shaped body contour with tissue deficit in transmission dosimetry

  16. Irregular menses predicts ovarian cancer: Prospective evidence from the Child Health and Development Studies.

    Science.gov (United States)

    Cirillo, Piera M; Wang, Erica T; Cedars, Marcelle I; Chen, Lee-May; Cohn, Barbara A

    2016-09-01

    We tested the hypothesis that irregular menstruation predicts lower risk for ovarian cancer, possibly due to less frequent ovulation. We conducted a 50-year prospective study of 15,528 mothers in the Child Health and Development Studies cohort recruited from the Kaiser Foundation Health Plan from 1959 to 1966. Irregular menstruation was classified via medical record and self-report at age 26. We identified 116 cases and 84 deaths due to ovarian cancer through 2011 via linkage to the California Cancer Registry and Vital Statistics. Contrary to expectation, women with irregular menstrual cycles had a higher risk of ovarian cancer incidence and mortality over the 50-year follow-up. Associations increased with age (p irregular menstruation and ovarian cancer-we unexpectedly found higher risk for women with irregular cycles. These women are easy to identify and many may have polycystic ovarian syndrome. Classifying high-risk phenotypes such as irregular menstruation creates opportunities to find novel early biomarkers, refine clinical screening protocols and potentially develop new risk reduction strategies. These efforts can lead to earlier detection and better survival for ovarian cancer. © 2016 UICC.

  17. Investigation on the relationship among sporadic Na, sporadic E, Field aligned irregularities and neutral winds

    Science.gov (United States)

    Sundararajan, Sridharan; Patra, Amit Kumar; Pant, Tarun; Gurubaran, Subramanian; Raghunath, Karnam

    In the Mesosphere and Lower Thermosphere region (80-100 km), metallic atoms, namely, sodium, potassium, lithium, Iron etc are formed due to ablation of meteors. The lidars based on resonance fluorescence principle has been used to study the vertical distribution of sodium atoms, because of their large abundance than other metals. The profiles of sodium density sometimes show enhancement by a factor of 2 than the normal layer in a narrow altitude region of 2 km and on these occasions, they are called sporadic sodium layer, or briefly Ns. On the other hand, there are observations on sporadic E and radar observations of Field Aligned Irregularities (FAI) associated with these sporadic E. Some investigations have been made to understand the relationship between sporadic E and FAI. Considering that sporadic E is composed of metallic ions and the time of metallic ions are larger compared to other ions, the sodium observations in the same height region would be of significant importance to understand the process involved. Despite a few past observations, no clear picture has emerged due to lack of simultaneous measurements of these parameters. The simultaneous observations of FAI echoes by the Indian MST radar and sodium concentration by the sodium lidar at Gadanki (13.5o N, 79.2o E) are being used to investigate the above mentioned relationship. The Sporadic E and neutral wind information are obtained from the ionosonde, meteor/MF radar observations from Trivandrum (8.5o N, 77E) and Tirunelveli (8.7o N, 77.8o E). The results obtained will be presented during the meeting.

  18. Excitation thresholds of field-aligned irregularities and associated ionospheric hysteresis at very high latitudes observed using SPEAR-induced HF radar backscatter

    Directory of Open Access Journals (Sweden)

    D. M. Wright

    2009-07-01

    Full Text Available On 10 October 2006 the SPEAR high power radar facility was operated in a power-stepping mode where both CUTLASS radars were detecting backscatter from the SPEAR-induced field-aligned irregularities (FAIs. The effective radiated power of SPEAR was varied from 1–10 MW. The aim of the experiment was to investigate the power thresholds for excitation (Pt and collapse (Pc of artificially-induced FAIs in the ionosphere over Svalbard. It was demonstrated that FAI could be excited by a SPEAR ERP of only 1 MW, representing only 1/30th of SPEAR's total capability, and that once created the irregularities could be maintained for even lower powers. The experiment also demonstrated that the very high latitude ionosphere exhibits hysteresis, where the down-going part of the power cycle provided a higher density of irregularities than for the equivalent part of the up-going cycle. Although this second result is similar to that observed previously by CUTLASS in conjunction with the Tromsø heater, the same is not true for the equivalent incoherent scatter measurements. The EISCAT Svalbard Radar (ESR failed to detect any hysteresis in the plasma parameters over Svalbard in stark contract with the measurements made using the Tromsø UHF.

  19. Excitation thresholds of field-aligned irregularities and associated ionospheric hysteresis at very high latitudes observed using SPEAR-induced HF radar backscatter

    Directory of Open Access Journals (Sweden)

    D. M. Wright

    2009-07-01

    Full Text Available On 10 October 2006 the SPEAR high power radar facility was operated in a power-stepping mode where both CUTLASS radars were detecting backscatter from the SPEAR-induced field-aligned irregularities (FAIs. The effective radiated power of SPEAR was varied from 1–10 MW. The aim of the experiment was to investigate the power thresholds for excitation (Pt and collapse (Pc of artificially-induced FAIs in the ionosphere over Svalbard. It was demonstrated that FAI could be excited by a SPEAR ERP of only 1 MW, representing only 1/30th of SPEAR's total capability, and that once created the irregularities could be maintained for even lower powers. The experiment also demonstrated that the very high latitude ionosphere exhibits hysteresis, where the down-going part of the power cycle provided a higher density of irregularities than for the equivalent part of the up-going cycle. Although this second result is similar to that observed previously by CUTLASS in conjunction with the Tromsø heater, the same is not true for the equivalent incoherent scatter measurements. The EISCAT Svalbard Radar (ESR failed to detect any hysteresis in the plasma parameters over Svalbard in stark contract with the measurements made using the Tromsø UHF.

  20. Modelling and Predicting the Breaking Strength and Mass Irregularity of Cotton Rotor-Spun Yarns Containing Cotton Fiber Recovered from Ginning Process by Using Artificial Neural Network Algorithm

    Directory of Open Access Journals (Sweden)

    Mohsen Shanbeh

    2011-01-01

    Full Text Available One of the main methods to reduce the production costs is waste recycling which is the most important challenge for the future. Cotton wastes collected from ginning process have desirable properties which could be used during spinning process. The purpose of this study was to develop predictive models of breaking strength and mass irregularity (CV% of cotton waste rotor-spun yarns containing cotton waste collected from ginning process by using the artificial neural network trained with backpropagation algorithm. Artificial neural network models have been developed based on rotor diameter, rotor speed, navel type, opener roller speed, ginning waste proportion and yarn linear density as input parameters. The parameters of artificial neural network model, namely, learning, and momentum rate, number of hidden layers and number of hidden processing elements (neurons were optimized to get the best predictive models. The findings showed that the breaking strength and mass irregularity of rotor spun yarns could be predicted satisfactorily by artificial neural network. The maximum error in predicting the breaking strength and mass irregularity of testing data was 8.34% and 6.65%, respectively.

  1. Investigating the Role of Gravity Wave on Equatorial Ionospheric Irregularities using SABER and C/NOFS Satellites Observations

    Science.gov (United States)

    Nigussie, M.; Damtie, B.; Moldwin, M.; Yizengaw, E.; Tesema, F.; Tebabal, A.

    2017-12-01

    Theoretical simulations have shown that gravity wave (GW) seeded perturbations amplified by Rayleigh-Taylor Instability (RTI) results in ESF (equatorial spread F); however, there have been limited observational studies using simultaneous observations of GW and ionospheric parameters. In this paper, for the fist time, simultaneous atmospheric temperature perturbation profiles that are due to GWs obtained from Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) on-board the TIMED satellite and equatorial in -situ ion density and vertical plasma drift velocity observations with and without ESF activity obtained from C/NOFS satellites are used to investigate the effect of GW on the generation of ESF. The horizontal and vertical wavelengths of ionospheric oscillations and GWs respectively have been estimated applying wavelet transforms. Cross wavelet analysis has also been applied between two closely observed profiles of temperature perturbations to estimate the horizontal wavelength of the GWs. Moreover, vertically propagating GWs that dissipate energy at the upper atmosphere have been investigated using spectral analysis compared with theoretical results. The analysis show that when the ion density shows strong post sunset irregularity between 20 and 24 LT, vertically upward drift velocities increase between 17 and 19 LT, but it becomes vertically downward when the ion density shows smooth variation. The horizontal wavelengths estimated from C/NOFS and SABER observations show excellent agreement when ion density observations show strong fluctuations; otherwise, they have poor agreement. It is also found that altitude profiles of potential energy of GW increases up to 90 km and then decreases significantly. It is found that the vertical wavelength of GW, corresponding to the dominant spectral power, ranges from about 7 km to 20 km regardless of the situation of the ionosphere; however, GWs with vertical wavelengths between 100 m to 1 km are found to

  2. Nonlinearly coupled dynamics of irregularities in the equatorial electrojet

    Energy Technology Data Exchange (ETDEWEB)

    Atul, J.K., E-mail: jkatulphysics@gmail.com [Department of Physics, College of Commerce under Magadh University, Patna 800020 (India); Sarkar, S. [FCIPT, Institute for Plasma Research, Gandhinagar 382428 (India); Singh, S.K. [Department of Physics, College of Commerce under Magadh University, Patna 800020 (India)

    2016-04-01

    Kinetic wave description is used to study the nonlinear influence of background Farley Buneman (FB) modes on the Gradient Drift (GD) modes in the equatorial electrojet ionosphere. The dominant nonlinearity is mediated through the electron flux term in the governing fluid equation which further invokes a turbulent current into the system. Electron dynamics reveals the modification in electron collision frequency and inhomogeneity scale length. It is seen that the propagation and growth rate of GD modes get modified by the background FB modes. Also, a new quasimode gets excited through the quadratic dispersion relation. Physical significance of coupled dynamics between the participating modes is also discussed. - Highlights: • Nonlinear influence of Farley Buneman mode on the Gradient drift mode, is investigated. • Electron collision frequency and density gradient scale length get modified. • A new quasimode gets excited due to the competition between these modes. • It seems to be important for modelling of Equatorial Electrojet current system.

  3. Nonlinearly coupled dynamics of irregularities in the equatorial electrojet

    International Nuclear Information System (INIS)

    Atul, J.K.; Sarkar, S.; Singh, S.K.

    2016-01-01

    Kinetic wave description is used to study the nonlinear influence of background Farley Buneman (FB) modes on the Gradient Drift (GD) modes in the equatorial electrojet ionosphere. The dominant nonlinearity is mediated through the electron flux term in the governing fluid equation which further invokes a turbulent current into the system. Electron dynamics reveals the modification in electron collision frequency and inhomogeneity scale length. It is seen that the propagation and growth rate of GD modes get modified by the background FB modes. Also, a new quasimode gets excited through the quadratic dispersion relation. Physical significance of coupled dynamics between the participating modes is also discussed. - Highlights: • Nonlinear influence of Farley Buneman mode on the Gradient drift mode, is investigated. • Electron collision frequency and density gradient scale length get modified. • A new quasimode gets excited due to the competition between these modes. • It seems to be important for modelling of Equatorial Electrojet current system.

  4. Hemolytic disease of the newborn caused by irregular blood subgroup (Kell, C, c, E, and e) incompatibilities: report of 106 cases at a tertiary-care centre.

    Science.gov (United States)

    Karagol, Belma Saygili; Zenciroglu, Aysegul; Okumus, Nurullah; Karadag, Nilgun; Dursun, Arzu; Hakan, Nilay

    2012-06-01

    To determine the clinical spectrum of hemolytic disease due to irregular blood subgroup incompatibility in hospitalized neonates. The medical records of the all hospitalized newborn patients diagnosed with indirect hyperbilirubinemia due to subgroup incompatibility in Kell, C, c, E, and e systems were included in the study. Data from 106 newborns with hemolytic jaundice due to irregular blood subgroups were retrospectively evaluated, and clinical and laboratory findings were compared between patients . The treatment modalities given to the patients of each subgroup types and the laboratory findings and treatment modalities of the cases according to Coombs tests results were also analyzed. Fetal affection of the hemolysis and also fetal losses due to irregular red-cell alloimmunization were not detected in prenatal course, as there was no follow-up of these pregnancies. The mean postnatal hospitalizing age was 6.1 ± 5.2 days after birth. The mean total bilirubin level and the mean hemoglobin value on hospitalization were 343.7 ± 63.3 µmol/L (=20.1 ± 3.7 mg/dL) and 14.9 ± 3.4 g/dL, respectively. Of 106 patients identified with irregular subgroup incompatibility, 40 infants (37.7%) were associated with C, 22 (20.8%) with c, 30 (28.3%) with E, 9 (8.5%) with e, and 5 (4.7%) with Kell subgroup system. Positive Coombs tests (either direct and/or indirect) occurred in 28.3% of the study cases. Hydrops fetalis was determined in 5 of 106 neonates (4.7%). Twenty-two of 106 (20.8%) patients required total exchange transfusion. Positive Coombs test in cases required total exchange transfusion was 63.6%. Our data expose the magnitude and spectrum of the potential developing severe hemolytic disease and immune hydrops due to irregular subgroup incompatibility. Minor group antibody screening is recommended both in the mother and the high-risk infants with hyperbilirubinemia and hemolytic disease of the newborn. Copyright © 2012 Thieme Medical Publishers, Inc., 333 Seventh

  5. Noninfectious differential diagnoses of pneumonia

    International Nuclear Information System (INIS)

    Wielandner, A.; Toelly, A.; Agarwal, P.; Bardach, C.

    2017-01-01

    In patients with a clinical suspicion of pneumonia, typical clinical and laboratory features along with the detection of infiltrates on chest X-ray are as a rule considered diagnostic and therapy is immediately initiated; however, studies have shown that in up to 5% of patients with an initial suspicion of pneumonia, another noninfectious pulmonary disease was the underlying cause. Early recognition and differentiation of diseases mimicking pneumonia are prerequisites for an adequate therapy. The aim of this review is to present the important noninfectious differential diagnoses of pneumonia and to provide the reader with tools for a systematic diagnostic approach. A literature search was carried out. As alterations in the lungs often result in similar imaging appearances and a differentiation between transudates, exsudates, blood and cells is not feasible by chest X-ray or CT, a systematic approach is essential to make an appropriate diagnosis. Hence, consideration of the temporal course, predominant pattern, distribution of findings, additional findings and clinical presentation are indispensable. (orig.) [de

  6. Alterations found with computerized tomography in newly diagnosed type 2 diabetics

    International Nuclear Information System (INIS)

    Bruna, J.

    1989-01-01

    In 28 newly diagnosed type 2 diabetic patients (insulin-independent), computerized tomography (CT) was used to determine the density of the pancreas and the kidneys, densities of the liver, spleen and blood in the abdominal aorta, and to investigate pathological changes in the tissues mentioned above. The results were correlated with laboratory findings. The following changes were found: decreased density of the pancreas (29.4 H) and the liver (49.1 H) and increased density of the spleen (56.3 H) and blood in the abdominal aorta (43.7 H). The decreased density of the pancreas appears to be connected with disorders of lipoprotein metabolism. The decreased liver density was related to increased energy intake by food and to overweight evaluated by Broc's index. Other CT findings in the newly diagnosed type 2 diabetics (changes in the size of the pancreas, and kidneys, kidney cysts, nephrolithiasis, sclerotic plaques on aorta) were not significant. (author). 2 tabs., 11 refs

  7. Dose calculations for irregular fields using three-dimensional first-scatter integration

    International Nuclear Information System (INIS)

    Boesecke, R.; Scharfenberg, H.; Schlegel, W.; Hartmann, G.H.

    1986-01-01

    This paper describes a method of dose calculations for irregular fields which requires only the mean energy of the incident photons, the geometrical properties of the irregular field and of the therapy unit, and the attenuation coefficient of tissue. The method goes back to an approach including spatial aspects of photon scattering for inhomogeneities for the calculation of dose reduction factors as proposed by Sontag and Cunningham (1978). It is based on the separation of dose into a primary component and a scattered component. The scattered component can generally be calculated for each field by integration over dose contributions from scattering in neighbouring volume elements. The quotient of this scattering contribution in the irregular field and the scattering contribution in the equivalent open field is then the correction factor for scattering in an irregular field. A correction factor for the primary component can be calculated if the attenuation of the photons in the shielding block is properly taken into account. The correction factor is simply given by the quotient of primary photons of the irregular field and the primary photons of the open field. (author)

  8. Method of determining effects of heat-induced irregular refractive index on an optical system.

    Science.gov (United States)

    Song, Xifa; Li, Lin; Huang, Yifan

    2015-09-01

    The effects of an irregular refractive index on optical performance are examined. A method was developed to express a lens's irregular refractive index distribution. An optical system and its mountings were modeled by a thermomechanical finite element (FE) program in the predicted operating temperature range, -45°C-50°C. FE outputs were elaborated using a MATLAB optimization routine; a nonlinear least squares algorithm was adopted to determine which gradient equation best fit each lens's refractive index distribution. The obtained gradient data were imported into Zemax for sequential ray-tracing analysis. The root mean square spot diameter, modulation transfer function, and diffraction ensquared energy were computed for an optical system under an irregular refractive index and under thermoelastic deformation. These properties are greatly reduced by the irregular refractive index effect, which is one-third to five-sevenths the size of the thermoelastic deformation effect. Thus, thermal analyses of optical systems should consider not only thermoelastic deformation but also refractive index irregularities caused by inhomogeneous temperature.

  9. The nature and source of irregular discharges to stormwater entering Sydney estuary, Australia

    International Nuclear Information System (INIS)

    Beck, H.J.; Birch, G.F.

    2014-01-01

    Irregular discharges of polluted stormwater into drainage systems during base flow (no rainfall) result in acute ecological impacts within fluvial and estuarine environments. In this study, metal and TSS concentrations were significantly more variable during business hours of weekdays (i.e. high-business activity) than weekends/public holidays (i.e. low-business activity) within three highly-urbanised catchments of Sydney estuary (Australia), as determined by analysing multivariate dispersion (PERMDISP). Concentrations of TSS and all metals analysed (Al, Ca, Cu, Fe, Mg, Pb and Zn) were also significantly greater during high- than low-business periods within at least one of the three catchments. In no case were concentrations significantly higher during low- than high-business periods. This pattern of contamination supports the hypothesis that commercial and industrial sources are major contributors of irregular discharges of contamination to Sydney estuary. Irregular discharges and consequential ecological impacts may be effectively reduced in this environment by focussing management efforts on these activities. - Highlights: • Irregular discharges of pollution have acute impacts on aquatic ecosystems. • These discharges were thought to be made during low activity periods, such as night. • Pollution was more concentrated and erratic during high- than low-business periods. • Timing of pollution suggests commercial and industrial activities are major sources. • Discharges effectively reduced by managing commercial and industrial activities. - Previously unreported irregular, illegal discharges of polluted stormwater released to estuaries result in acute ecological impacts and are potentially related to commercial/industrial activities

  10. 30 MHz radar observations of artificial E region field-aligned plasma irregularities

    Directory of Open Access Journals (Sweden)

    D. L. Hysell

    2008-02-01

    Full Text Available Artificial E region field aligned irregularities (FAIs have been observed during heating experiments at the HAARP facility using a new 30 MHz coherent scatter radar imager deployed near Homer, Alaska. Irregularities were observed during brief experiments on three quiet days in July and August, 2007, when the daytime E region critical frequency was close to 3 MHz. Irregularities were consistently generated and detected during experiments with O-mode HF pumping on zenith with a 1-min on, 1-min off CW modulation. The scattering cross sections, rise, and fall times of the echoes were observed as well as their spectral properties. Results were found to be mainly in agreement with observations from other mid- and high-latitude sites with some discrepancies. Radar images of the irregularity-filled volume on one case exhibited clear variations in backscatter power and Doppler shift across the volume. The images furthermore show the emergence of a small irregularity-filled region to the south southwest of the main region in the approximate direction of magnetic zenith.

  11. Using forbidden ordinal patterns to detect determinism in irregularly sampled time series.

    Science.gov (United States)

    Kulp, C W; Chobot, J M; Niskala, B J; Needhammer, C J

    2016-02-01

    It is known that when symbolizing a time series into ordinal patterns using the Bandt-Pompe (BP) methodology, there will be ordinal patterns called forbidden patterns that do not occur in a deterministic series. The existence of forbidden patterns can be used to identify deterministic dynamics. In this paper, the ability to use forbidden patterns to detect determinism in irregularly sampled time series is tested on data generated from a continuous model system. The study is done in three parts. First, the effects of sampling time on the number of forbidden patterns are studied on regularly sampled time series. The next two parts focus on two types of irregular-sampling, missing data and timing jitter. It is shown that forbidden patterns can be used to detect determinism in irregularly sampled time series for low degrees of sampling irregularity (as defined in the paper). In addition, comments are made about the appropriateness of using the BP methodology to symbolize irregularly sampled time series.

  12. On the total irregularity strength of caterpillar with each internal vertex has degree three

    Science.gov (United States)

    Indriati, Diari; Rosyida, Isnaini; Widodo

    2018-04-01

    Let G be a simple, connected and undirected graph with vertex set V and edge set E. A total k-labeling f:V \\cup E\\to \\{1,2,\\ldots,k\\} is defined as totally irregular total k-labeling if the weights of any two different both vertices and edges are distinct. The weight of vertex x is defined as wt(x)=f(x)+{\\sum }xy\\in Ef(xy), while the weight of edge xy is wt(xy)=f(x)+f(xy)+f(y). A minimum k for which G has totally irregular total k-labeling is mentioned as total irregularity strength of G and denoted by ts(G). This paper contains investigation of totally irregular total k-labeling and determination of their total irregularity strengths for caterpillar graphs with each internal vertex between two stars has degree three. The results are ts({S}n,3,n)=\\lceil \\frac{2n}{2}\\rceil, ts({S}n,3,3,n)=\\lceil \\frac{2n+1}{2}\\rceil and ts({S}n,3,3,3,n)=\\lceil \\frac{2n+2}{2}\\rceil for n > 4:

  13. Simulating Seismic Wave Propagation in Viscoelastic Media with an Irregular Free Surface

    Science.gov (United States)

    Liu, Xiaobo; Chen, Jingyi; Zhao, Zhencong; Lan, Haiqiang; Liu, Fuping

    2018-05-01

    In seismic numerical simulations of wave propagation, it is very important for us to consider surface topography and attenuation, which both have large effects (e.g., wave diffractions, conversion, amplitude/phase change) on seismic imaging and inversion. An irregular free surface provides significant information for interpreting the characteristics of seismic wave propagation in areas with rugged or rapidly varying topography, and viscoelastic media are a better representation of the earth's properties than acoustic/elastic media. In this study, we develop an approach for seismic wavefield simulation in 2D viscoelastic isotropic media with an irregular free surface. Based on the boundary-conforming grid method, the 2D time-domain second-order viscoelastic isotropic equations and irregular free surface boundary conditions are transferred from a Cartesian coordinate system to a curvilinear coordinate system. Finite difference operators with second-order accuracy are applied to discretize the viscoelastic wave equations and the irregular free surface in the curvilinear coordinate system. In addition, we select the convolutional perfectly matched layer boundary condition in order to effectively suppress artificial reflections from the edges of the model. The snapshot and seismogram results from numerical tests show that our algorithm successfully simulates seismic wavefields (e.g., P-wave, Rayleigh wave and converted waves) in viscoelastic isotropic media with an irregular free surface.

  14. Morning Cortisol Levels and Perceived Stress in Irregular Shift Workers Compared with Regular Daytime Workers

    Directory of Open Access Journals (Sweden)

    Harri Lindholm

    2012-01-01

    Full Text Available The 24/7 work environment and irregular shifts may markedly enhance the psychological pressure of media work. Changes in the hypothalamic-pituitary-adrenal axis reflect adaptation to stress. We analysed the correlation between subjective stress, sleep, salivary cortisol, and melatonin hormones among Finnish media workers with regular daytime work (RDW and with irregular shift work (ISW while controlling confounders. From 874 employees with regular daytime work or with irregular shift work, 70 employees from both groups were randomly selected. The final number of employees with a complete salivary cortisol profile was 66 in the RDW group and 65 in the ISW group. Five saliva samples were gathered from each subject before and during a working day. The salivary cortisol level of the sample taken 60 minutes after awakening (T1 was compared to the salivary cortisol level taken immediately after awakening (T0, T1/T0 ratio. The ratio was higher in the ISW group than in RDW group. Irregular shift work (P<0.001, severe stress (P<0.05, and less sleep (P<0.05 were independently associated with an augmented cortisol response after awakening. A stressful work environment and irregular shift work enhance cortisol excretion after waking. In the long run, this may become detrimental to health.

  15. Application of the pothole DAF method to vehicles traversing periodic roadway irregularities

    Science.gov (United States)

    Pesterev, A. V.; Bergman, L. A.; Tan, C. A.; Yang, B.

    2005-01-01

    This paper is a sequel to the work discussed in Pesterev et al. (Journal of Sound and Vibration, in press). In that paper, it was suggested that the technique to determine the effect of a local road surface irregularity on the dynamics of a vehicle modelled as a linear multi-degree-of-freedom system relies on the so-called pothole dynamic amplification factor (DAF), which is a complex-valued function specific to the irregularity shape. This paper discusses the companion problem of how to determine the DAF function for an irregularity represented as a superposition of simpler ones. Another purpose of this paper is to demonstrate the application of the pothole DAF functions technique to finding a priori estimates of the effect of irregularities with a repeated structure. Specifically, we solve the problem of finding the conditions under which the dynamic effect of two identical potholes located one after another is greater than that due to the single pothole. We also find the estimate for the number of periods of a periodic irregularity that are sufficient in order to consider the oscillator response as steady state. The discussions are illustrated by numerical examples.

  16. Is CT effective in diagnosing the acute appendicitis?: Focus on comparison of unenhanced CT with barium enema

    International Nuclear Information System (INIS)

    Choi, Seong Hee; Hahm, So Hee; Kang Jin Hwa; Moon, Jeong Hwa

    1994-01-01

    To evaluate the role of unenhanced CT in diagnosing the acute appendicitis. We retrospectively analyzed conventional contrast-enhanced abdominal CT scans of 197 normal patients and barium enemas of 26 out of the 197 patients. Additional unenhanced CT scans of right lower abdomen were performed on 30 patients who were suspected of having acute appendicitis; barium enema was performed in 26 patients. In the analysis of the conventional CT scans, we could detect 132 (67%) normal appendices. On barium enema of 26 out of 197 patients, abruptly narrowed appendix was visualized in 5 cases and luminal irregularity in 4 cases but all 26 cases showed normal appendix on CT. In the 30 cases of unenhanced CT, all appendices were visualized. Among 12 cases which were proved as acute appendicitis, barium enema was done in 10 cases; abruptly narrowed appendix was shown in 3 and luminal irregularity in 1. Among 18 cases which were diagnosed as normal appendix, nonvisualization of appendix was in 1 case, abruptly narrowed lumen in 3, and luminal irregularity in 9. Unenhanced CT in the area of the cecum may be an effective and safe diagnostic tool acute appendicitis

  17. Actors and factors in the governance of irregular migration : a comparative analysis of Albanian, Georgian, Ukrainian, Pakistani and Afghani irregular flows to Greece

    OpenAIRE

    TRIANDAFYLLIDOU, Anna

    2015-01-01

    Proceedings from the conference "Governing Irregular Migration : States, Actors and Intermediaries", Athens 8-9 July 2015 The loss of over a thousand human lives in the effort to cross the Mediterranean during April 2015 has once again drawn media and political attention to the challenges that the EU is facing in its efforts to govern migration and asylum. However, what seems to be still far from complete is our (the experts and the politicians) understanding of what drives people to put t...

  18. Prices and costs of irregularity in renewable resources in the liberalized electricity markets

    International Nuclear Information System (INIS)

    Menanteau, Ph.; Finon, D.

    2004-01-01

    The problems raised by incorporating irregular production are of a technical nature (risk of non-availability during peak demand, the requirements for additional reserves) but the electricity markets methods of operation impose economic penalties, which greatly exceed these additional technical costs. In this document, the authors examine the nature of the technical problems posed by irregularity of production and the additional costs resulting from this, and then analyse the origins of the economic penalties that the operation of liberalized electricity markets impose, taking in particular the example of the British market, the New Energy Trading Arrangement (NETA). It would appear that the markets' operating rules may conflict, in certain cases, with the targets for promoting electricity generation from renewable resources. Two types of solutions can therefore be envisaged: a set of rules to limit the impact on irregular production or collective handling of the adjustment to production from renewable resources as already exists in the Nordic electricity markets. (authors)

  19. Working irregular shift patterns is associated with functional constipation among healthy trainee nurses

    Directory of Open Access Journals (Sweden)

    Ali Ebrahim

    2017-11-01

    Full Text Available The circadian system has a role in regulating gastrointestinal physiology. Perturbation of this system is associated with gastrointestinal tract dysfunction. Shiftwork and poor sleep quality are associated with functional gastrointestinal disorders among many professional groups. This study compared bowel habits between trainee nurses with regular and irregular patterns of shiftwork. Male and female nursing students, enrolled on the first year (regular shifts; n=49 and the fourth year (irregular shifts, n=48 of a nursing degree course were surveyed. Questionnaires were used to assess functional diarrhea and constipation over a three month period. The prevalence of functional constipation among regular shift workers was lower than that found among irregular shift workers; 31.3% and 61.2%, respectively. There was no difference between the two groups in relation to the prevalence of diarrhea. This suggests an association between shiftwork and functional constipation, but not with functional diarrhea.

  20. Spiking irregularity and frequency modulate the behavioral report of single-neuron stimulation.

    Science.gov (United States)

    Doron, Guy; von Heimendahl, Moritz; Schlattmann, Peter; Houweling, Arthur R; Brecht, Michael

    2014-02-05

    The action potential activity of single cortical neurons can evoke measurable sensory effects, but it is not known how spiking parameters and neuronal subtypes affect the evoked sensations. Here, we examined the effects of spike train irregularity, spike frequency, and spike number on the detectability of single-neuron stimulation in rat somatosensory cortex. For regular-spiking, putative excitatory neurons, detectability increased with spike train irregularity and decreasing spike frequencies but was not affected by spike number. Stimulation of single, fast-spiking, putative inhibitory neurons led to a larger sensory effect compared to regular-spiking neurons, and the effect size depended only on spike irregularity. An ideal-observer analysis suggests that, under our experimental conditions, rats were using integration windows of a few hundred milliseconds or more. Our data imply that the behaving animal is sensitive to single neurons' spikes and even to their temporal patterning. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Application of Wuhan Ionospheric Oblique Backscattering Sounding System (WIOBSS) for the investigation of midlatitude ionospheric irregularities

    Science.gov (United States)

    Wang, Jin; Zhou, Xiaoming; Qiao, Lei; Gong, Wanlin

    2018-03-01

    An upgrade of Wuhan Ionospheric Backscattering Sounding System (WIOBSS) was developed in 2015. Based on the Universal Serial Bus (USB), and a high performance FPGA, the newly designed WIOBSS has a completely digital structure, which makes it portable and flexible. Two identical WIOBSSs, which were situated at Mile (24.31°N, 103.39°E) and Puer (22.74°N, 101.05°E) respectively, were used to investigate the ionospheric irregularities. The comparisons of group distance, Doppler shift and width between Mile-Puer and Puer-Mile VHF ionospheric propagation paths indicate that the reciprocity of the irregularities is satisfied at midlatitude region. The WIOBSS is robust in the detection of ionospheric irregularities.

  2. Institutional Root Cause of the Irregularity of Social Security Funds in China

    Institute of Scientific and Technical Information of China (English)

    Bingwen Zheng

    2007-01-01

    This paper analyzes institutional defects in the Chinese social security system, based on irregularities in social security funds revealed in the Audit Report by the China National Audit Office. The author divides the irregularities into five categories according to the nature of fund use. The results show that the institutional root cause of the irregularities lies in the unreasonable design and operation of the social security system, which currently faces management and institutional risks. This paper argues that simple rhetoric about strengthening regulation and supervision cannot help to reduce illegal practices, or to realize risk control. The only solution is to reform the social security system. Specifically, the Chinese Government should regulate the administrative cost of the social security system,and the behavior of its agencies, through legislation, reform the investment regime to increase rate of return of pension assets, and adjust and reshape the existing social security system, so as to elevate its pooling level.

  3. On the areas of various bodies in the Euclidean space: The case of irregular convex polygons

    International Nuclear Information System (INIS)

    Ozoemena, P.C.

    1988-11-01

    A theorem is proposed for the areas of n-sided irregular convex polygons, of given length of sides. The theorem is illustrated as a simple but powerful one in estimating the areas of irregular polygons, being dependent only on the number of sides n (and not on any of the explicit angles) of the irregular polygon. Finally, because of the global symmetry shown by equilateral triangles, squares and circles under group (gauge) theory, the relationships governing their areas, when they are inscribed or escribed in one another are discussed as riders, and some areas of their applications in graph theory, ratios and maxima and minima problems of differential calculus briefly mentioned. (author). 11 refs, 6 figs, 1 tab

  4. Multiple frequency radar observations of high-latitude E region irregularities in the HF modified ionosphere

    International Nuclear Information System (INIS)

    Noble, S.T.; Djuth, F.T.; Jost, R.J.

    1987-01-01

    In September 1983, experiments were conducted in Scandinavia using the high-power heating facility near Tromso, Norway. The purpose of the HF ionospheric modification experiments was to investigate the behavior of artificially produced E region irregularities at auroral latitudes. The majority of observations were made with backscatter radars operating at 46.9 and 143.8 MHz, but limited observations were also made at 21.4 and 140.0 MHz. These radars are sensitive to irregularities having scale lengths of between 1 and 7 m across the geomagnetic field lines. The growth and decay of the irregularities are scale length dependent with the shorter lengths growing and dissipating more rapidly than the longer lengths (e-folding growth times = 10 1 --10 2 ms; decay times = 10 2 --10 3 ms). During periods of full power ordinary mode heating, irregularities having peak cross sections of 10 4 m 2 at 46.9 MHz and 10 5 m 2 at 143.8 MHz are observed. However, the cross sections normally measured are 1 to 2 orders of magnitude smaller than the peak values. The cross sections are nonlinearly dependent on the HF power and begin to saturate at levels greater than 50--75 percent of full power. Past E and F region data from Arecibo are used in conjunction with the Tromso measurements to ascertain the relative roles played by various mechanisms in exciting irregularities. In the E region, the results tend to favor those instability processes which operate at the upper hybrid resonance level (e.g., thermal parametric and resonance instabilities) over those that operate at the reflection level (e.g., parametric decay instability). However, it is likely that anyh of the mechanisms studied could at times contribute to irregularity production in the E regions

  5. The majority of irregular menstrual cycles in adolescence are ovulatory: results of a prospective study.

    Science.gov (United States)

    Peña, Alexia S; Doherty, Dorota A; Atkinson, Helen C; Hickey, Martha; Norman, Robert J; Hart, Roger

    2018-03-01

    While ovulation is most likely to occur in adolescent girls with regular menstrual cycles, there are limited data on the incidence of ovulation in girls with irregular menstrual cycles in early postmenarcheal years. The aim of the study was to evaluate the presence of ovulation in healthy postmenarcheal girls with irregular menstrual cycles. Prospective cohort study over 12 weeks including 40 healthy postmenarcheal girls recruited from the population-based cohort of adolescents from Western Australian Pregnancy Cohort (Raine) Study with irregular menstrual cycles defined by either menstrual cycles 35 days in duration or cycle length that varied from month to month by >4 days according to menstrual diaries. Ovulation defined by urinary pregnanediol-3α-glucuronide/creatinine measurements higher than three times above minimum value obtained from 12 samples (1 per week). Forty girls (37 Caucasians) with irregular menstrual cycles aged 15.1 (median (IQR) 14.9-15.4) years who were 2.3 (1.9-3.3) years postmenarche were assessed. Urinary pregnanediol-3α-glucuronide/creatinine values identified that 33 girls (82.5%) ovulated during the 3 months of observation and 7 girls had anovulatory cycles. Menstrual diaries collected for a median (IQR) of 159 (137.5-188.2) days showed median minimal and maximum menstrual cycle duration of 24 (11.5-29) and 38.5 (35-48) days, respectively. A large proportion of healthy adolescent girls with irregular menstrual cycles are still ovulating despite irregular and infrequent menses. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  6. Spatial relationship of 1-meter equatorial spread-F irregularities and depletions in total electron content

    International Nuclear Information System (INIS)

    Tsunoda, R.T.; Towle, D.M.

    1979-01-01

    An experiment was conducted at Kwajalein Atoll, Marshall Islands to investigate the spatial relationship of 1-m equatorial spread-F irregularities to total electron content (TEC) depletions. A high-power radar was operated (1) in a backscatter scan mode to spatially map the distribution of 1-m irregularities, and (2) in a dual-frequency, satellite-track mode to obtain the longitudinal TEC variations. We show that radar backscatter ''plumes'' found in the disturbed, nighttime equatorial ionosphere are longitudinally coincident with TEC depletions. We suggest that the TEC depletions are probably due to the presence of plasma ''bubbles'' in the equatorial F layer

  7. Controllable irregular melting induced by atomic segregation in bimetallic clusters with fabricating different initial configurations

    International Nuclear Information System (INIS)

    Li Guojian; Liu Tie; Wang Qiang; Lue Xiao; Wang Kai; He Jicheng

    2010-01-01

    The melting process of Co, Co-Cu and Co-Ni clusters with different initial configurations is studied in molecular dynamics by a general embedded atom method. An irregular melting, at which energy decreases as the temperature increase near the melting point, is found in the onion-like Co-Cu-Co clusters, but not in the mixed Co-Cu and onion-like Co-Ni-Co clusters. From the analysis of atomic distributions and energy variation, the results indicate the irregular melting is induced by Cu atomic segregation. Furthermore, this melting can be controlled by doping hetero atoms with different surface energies and controlling their distributions.

  8. Regular-, irregular-, and pseudo-character processing in Chinese: The regularity effect in normal adult readers

    Directory of Open Access Journals (Sweden)

    Dustin Kai Yan Lau

    2014-03-01

    Full Text Available Background Unlike alphabetic languages, Chinese uses a logographic script. However, the pronunciation of many character’s phonetic radical has the same pronunciation as the character as a whole. These are considered regular characters and can be read through a lexical non-semantic route (Weekes & Chen, 1999. Pseudocharacters are another way to study this non-semantic route. A pseudocharacter is the combination of existing semantic and phonetic radicals in their legal positions resulting in a non-existing character (Ho, Chan, Chung, Lee, & Tsang, 2007. Pseudocharacters can be pronounced by direct derivation from the sound of its phonetic radical. Conversely, if the pronunciation of a character does not follow that of the phonetic radical, it is considered as irregular and can only be correctly read through the lexical-semantic route. The aim of the current investigation was to examine reading aloud in normal adults. We hypothesized that the regularity effect, previously described for alphabetical scripts and acquired dyslexic patients of Chinese (Weekes & Chen, 1999; Wu, Liu, Sun, Chromik, & Zhang, 2014, would also be present in normal adult Chinese readers. Method Participants. Thirty (50% female native Hong Kong Cantonese speakers with a mean age of 19.6 years and a mean education of 12.9 years. Stimuli. Sixty regular-, 60 irregular-, and 60 pseudo-characters (with at least 75% of name agreement in Chinese were matched by initial phoneme, number of strokes and family size. Additionally, regular- and irregular-characters were matched by frequency (low and consistency. Procedure. Each participant was asked to read aloud the stimuli presented on a laptop using the DMDX software. The order of stimuli presentation was randomized. Data analysis. ANOVAs were carried out by participants and items with RTs and errors as dependent variables and type of stimuli (regular-, irregular- and pseudo-character as repeated measures (F1 or between subject

  9. The transition from regular to irregular motions, explained as travel on Riemann surfaces

    International Nuclear Information System (INIS)

    Calogero, F; Santini, P M; Gomez-Ullate, D; Sommacal, M

    2005-01-01

    We introduce and discuss a simple Hamiltonian dynamical system, interpretable as a three-body problem in the (complex) plane and providing the prototype of a mechanism explaining the transition from regular to irregular motions as travel on Riemann surfaces. The interest of this phenomenology-illustrating the onset in a deterministic context of irregular motions-is underlined by its generality, suggesting its eventual relevance to understand natural phenomena and experimental investigations. Here only some of our main findings are reported, without detailing their proofs: a more complete presentation will be published elsewhere

  10. Low density in liver of idiopathic portal hypertension

    International Nuclear Information System (INIS)

    Ishito, Hiroyuki

    1988-01-01

    In order to evaluate the diagnostic value of low density in liver on computed tomography (CT), CT scans of 11 patients with idiopathic portal hypertension (IPH) were compared with those from 22 cirrhotic patients, two patients with scarred liver and 16 normal subjects. Low densities on plain CT scans in patients with IPH were distinctly different from those observed in normal liver. Some of the low densities had irregular shape with unclear margin and were scattered near the liver surface, and others had vessel-like structures with unclear margin and extended as far as near the liver surface. Ten of the 11 patients with IPH had low densities mentioned above, while none of the 22 cirrhotic patients had such low densities. The present results suggest that the presence of low densities in liver on plain CT scan is clinically beneficial in diagnosis of IPH. (author)

  11. Difficult diagnoses in the skeletal radiology

    International Nuclear Information System (INIS)

    Freyschmidt, Juergen

    2013-01-01

    The book on difficult diagnoses in the skeletal radiology discusses the path from symptom to diagnoses including image interpretation. Specific case studies concern the skull, the spinal cord, pelvis, shoulder and chest, upper and lower extremities. The used radiological techniques include projecting radiography, computerized tomography, scintiscanning, PET/CT, NNR imaging and ultrasonography.

  12. From experience : applying the risk diagnosing methodology

    NARCIS (Netherlands)

    Keizer, J.A.; Halman, J.I.M.; Song, X.M.

    2002-01-01

    No risk, no reward. Companies must take risks to launch new products speedily and successfully. The ability to diagnose and manage risks is increasingly considered of vital importance in high-risk innovation. This article presents the Risk Diagnosing Methodology (RDM), which aims to identify and

  13. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... website. Skip to main content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open ... Diagnosed with Cancer You are here Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation ...

  14. Immunoparesis in newly diagnosed Multiple Myeloma patients

    DEFF Research Database (Denmark)

    Sorrig, Rasmus; Klausen, Tobias W.; Salomo, Morten

    2017-01-01

    Immunoparesis (hypogammaglobulinemia) is associated to an unfavorable prognosis in newly diagnosed Multiple myeloma (MM) patients. However, this finding has not been validated in an unselected population-based cohort. We analyzed 2558 newly diagnosed MM patients in the Danish Multiple Myeloma...

  15. From experience: applying the risk diagnosing methodology

    NARCIS (Netherlands)

    Keizer, Jimme A.; Halman, Johannes I.M.; Song, Michael

    2002-01-01

    No risk, no reward. Companies must take risks to launch new products speedily and successfully. The ability to diagnose and manage risks is increasingly considered of vital importance in high-risk innovation. This article presents the Risk Diagnosing Methodology (RDM), which aims to identify and

  16. The failure diagnoses of nuclear reactor systems

    International Nuclear Information System (INIS)

    Sheng Huanxing.

    1986-01-01

    The earlier period failure diagnoses can raise the safety and efficiency of nuclear reactors. This paper first describes the process abnormality monitoring of core barrel vibration in PWR, inherent noise sources in BWR, sodium boiling in LMFBR and nuclear reactor stability. And then, describes the plant failure diagnoses of primary coolant pumps, loose parts in nuclear reactors, coolant leakage and relief valve location

  17. Diagnosing differences between business process models

    NARCIS (Netherlands)

    Dijkman, R.M.; Dumas, M.; Reichert, M.; Shan, M.-C.

    2008-01-01

    This paper presents a technique to diagnose differences between business process models in the EPC notation. The diagnosis returns the exact position of a difference in the business process models and diagnoses the type of a difference, using a typology of differences developed in previous work.

  18. Non-stationary random vibration analysis of a 3D train-bridge system using the probability density evolution method

    Science.gov (United States)

    Yu, Zhi-wu; Mao, Jian-feng; Guo, Feng-qi; Guo, Wei

    2016-03-01

    Rail irregularity is one of the main sources causing train-bridge random vibration. A new random vibration theory for the coupled train-bridge systems is proposed in this paper. First, number theory method (NTM) with 2N-dimensional vectors for the stochastic harmonic function (SHF) of rail irregularity power spectrum density was adopted to determine the representative points of spatial frequencies and phases to generate the random rail irregularity samples, and the non-stationary rail irregularity samples were modulated with the slowly varying function. Second, the probability density evolution method (PDEM) was employed to calculate the random dynamic vibration of the three-dimensional (3D) train-bridge system by a program compiled on the MATLAB® software platform. Eventually, the Newmark-β integration method and double edge difference method of total variation diminishing (TVD) format were adopted to obtain the mean value curve, the standard deviation curve and the time-history probability density information of responses. A case study was presented in which the ICE-3 train travels on a three-span simply-supported high-speed railway bridge with excitation of random rail irregularity. The results showed that compared to the Monte Carlo simulation, the PDEM has higher computational efficiency for the same accuracy, i.e., an improvement by 1-2 orders of magnitude. Additionally, the influences of rail irregularity and train speed on the random vibration of the coupled train-bridge system were discussed.

  19. Sedimentation of bidisperse, uncharged colloidal sphere suspensions: Influence of viscosity and irregular surfaces

    NARCIS (Netherlands)

    Thies-Weesie, Dominique M. E.; Philipse, Albert P.; Lekkerkerker, Henk N. W.

    1996-01-01

    The sedimentation velocity of uncharged, nonaggregated silica spheres under gravity is strongly reduced after addition of small amounts of nonsedimenting small spheres. This reduction is largely due to surface irregularities on a nanoscale of the large spheres at which a limited number of small

  20. Metaphyseal cortical irregularities in children: A new perspective on a multi-focal growth variant

    International Nuclear Information System (INIS)

    Keats, T.E.; Joyce, J.M.

    1984-01-01

    The occurrence of metaphyseal cortical irregularities in adolescents in many different bones indicates a commonality of these lesions as a variation of normal growth, rater than a stress or avulsive by-product. The histologically recognized incomplete nature of the metaphysical cortex in children offers an attractive explanation for this phenomenon. (orig.)

  1. An irregular grid approach for pricing high-dimensional American options

    NARCIS (Netherlands)

    Berridge, S.J.; Schumacher, J.M.

    2008-01-01

    We propose and test a new method for pricing American options in a high-dimensional setting. The method is centered around the approximation of the associated complementarity problem on an irregular grid. We approximate the partial differential operator on this grid by appealing to the SDE

  2. Lateralized effects of orthographical irregularity and auditory memory load on the kinematics of transcription typewriting.

    Science.gov (United States)

    Bloemsaat, Gijs; Van Galen, Gerard P; Meulenbroek, Ruud G J

    2003-05-01

    This study investigated the combined effects of orthographical irregularity and auditory memory load on the kinematics of finger movements in a transcription-typewriting task. Eight right-handed touch-typists were asked to type 80 strings of ten seven-letter words. In half the trials an irregularly spelt target word elicited a specific key press sequence of either the left or right index finger. In the other trials regularly spelt target words elicited the same key press sequence. An auditory memory load was added in half the trials by asking participants to remember the pitch of a tone during task performance. Orthographical irregularity was expected to slow down performance. Auditory memory load, viewed as a low level stressor, was expected to affect performance only when orthographically irregular words needed to be typed. The hypotheses were confirmed. Additional analysis showed differential effects on the left and right hand, possibly related to verbal-manual interference and hand dominance. The results are discussed in relation to relevant findings of recent neuroimaging studies.

  3. Irregular migration and informal economy in Southern and Central-Eastern Europe: breaking the vicious cycle?

    Science.gov (United States)

    Maroukis, Thanos; Iglicka, Krystyna; Gmaj, Katarzyna

    2011-01-01

    The flexible and cheap labour that European “post-industrial” economies are in need of is often facilitated by undeclared labour. The undocumented migrant, from his/her part, relatively easily finds work that suits his -- at least initial -- plans. What lies behind this nexus between irregular migration and informal economy? To what extent can this nexus be attributed to the structural features of the so-called “secondary”, as opposed to “primary”, labour market? And how does migration policy correlate with this economic context and lead to the entrapment of migrants in irregularity? Finally, can this vicious cycle of interests and life-strategies be broken and what does the experience of the migrants indicate in this respect? This paper addresses these questions via an exploration of the grounds upon which irregular migration and the shadow economy complement each other in southern Europe (SE) and central and Eastern Europe (CEE) (two regions at different points in the migration cycle). In doing so, the dynamic character of the nexus between informal economy and irregular migration will come to the fore, and the abstract identity of the “average” undocumented migrant will be deconstructed.

  4. PERIODIC ORBIT FAMILIES IN THE GRAVITATIONAL FIELD OF IRREGULAR-SHAPED BODIES

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Yu [State Key Laboratory of Astronautic Dynamics, Xi’an Satellite Control Center, Xi’an 710043 (China); Baoyin, Hexi, E-mail: jiangyu_xian_china@163.com [School of Aerospace Engineering, Tsinghua University, Beijing 100084 (China)

    2016-11-01

    The discovery of binary and triple asteroids in addition to the execution of space missions to minor celestial bodies in the past several years have focused increasing attention on periodic orbits around irregular-shaped celestial bodies. In the present work, we adopt a polyhedron shape model for providing an accurate representation of irregular-shaped bodies and employ the model to calculate their corresponding gravitational and effective potentials. We also investigate the characteristics of periodic orbit families and the continuation of periodic orbits. We prove a fact, which provides a conserved quantity that permits restricting the number of periodic orbits in a fixed energy curved surface about an irregular-shaped body. The collisions of Floquet multipliers are maintained during the continuation of periodic orbits around the comet 1P/Halley. Multiple bifurcations in the periodic orbit families about irregular-shaped bodies are also discussed. Three bifurcations in the periodic orbit family have been found around the asteroid 216 Kleopatra, which include two real saddle bifurcations and one period-doubling bifurcation.

  5. Modalities of Tonometry and their Accuracy with Respect to Corneal Thickness and Irregularities

    Science.gov (United States)

    De Moraes, Carlos Gustavo V.; Prata, Tiago S.; Liebmann, Jeffrey; Ritch, Robert

    2010-01-01

    Recent advances in tonometry have led to the development of a number of devices with differing clinical applications. Their role in cases of abnormal corneal thickness and surface irregularities is particularly important, as inaccurate estimation of the true intraocular pressure (IOP) in such cases may lead to suboptimal evaluation. The purpose of the present review was to evaluate the accuracy of the most widely used devices in cases of corneal thickness and surface irregularities, based on a survey of the published literature. The analysis was based on a Medline search focusing mainly on papers that have evaluated the devices’ accuracy with respect to corneal thickness and irregularities. Nine device types (Goldmann tonometer, Tono-Pen, Perkins tonometer, Ocular Response Analyzer, non-contact tonometer, pneumatonometer, I-Care rebound tonometer, Pascal dynamic contour tonometer (DCT) and Phosphene tonometer) were described in detail. Moreover, the physical principles and major utility of each tonometer were compared. Each of the many different commercially available tonometers has specific advantages and disadvantages. New non-invasive technologies are getting closer to a precise estimation of the true IOP. However, among all tonometers, none is highly accurate when both corneal thickness and surface irregularities are present. Fifty years after its development, Goldmann tonometry remains the gold standard to which all other devices are compared.

  6. Simultaneous radar and spaced receiver VHF scintillation observations of ESF irregularities

    Directory of Open Access Journals (Sweden)

    D. Tiwari

    2006-07-01

    Full Text Available Simultaneous observations of equatorial spread F (ESF irregularities made on 10 nights during March-April 1998 and 1999, using an 18-MHz radar at Trivandrum (77° E, 8.5° N, dip 0.5° N and two spaced receivers recording scintillations on a 251-MHz signal at Tirunelveli (77.8° E, 8.7° N, dip 0.4° N, have been used to study the evolution of Equatorial Spread F (ESF irregularities. Case studies have been carried out on the day-to-day variability in ESF structure and dynamics, as observed by 18-MHz radar, and with spaced receiver measurements of average zonal drift Vo of the 251-MHz radio wave diffraction pattern on the ground, random velocity Vc, which is a measure of random changes in the characteristics of scintillation-producing irregularities, and maximum cross-correlation CI of the spaced receivers signals. Results show that in the initial phase of plasma bubble development, the greater the maximum height of ESF irregularities responsible for the radar backscatter, the greater the decorrelation is of the spaced receiver scintillation signals, indicating greater turbulence. The relationship of the maximum spectral width derived from the radar observations and CI also supports this result.

  7. Simultaneous radar and spaced receiver VHF scintillation observations of ESF irregularities

    Directory of Open Access Journals (Sweden)

    D. Tiwari

    2006-07-01

    Full Text Available Simultaneous observations of equatorial spread F (ESF irregularities made on 10 nights during March-April 1998 and 1999, using an 18-MHz radar at Trivandrum (77° E, 8.5° N, dip 0.5° N and two spaced receivers recording scintillations on a 251-MHz signal at Tirunelveli (77.8° E, 8.7° N, dip 0.4° N, have been used to study the evolution of Equatorial Spread F (ESF irregularities. Case studies have been carried out on the day-to-day variability in ESF structure and dynamics, as observed by 18-MHz radar, and with spaced receiver measurements of average zonal drift Vo of the 251-MHz radio wave diffraction pattern on the ground, random velocity Vc, which is a measure of random changes in the characteristics of scintillation-producing irregularities, and maximum cross-correlation CI of the spaced receivers signals. Results show that in the initial phase of plasma bubble development, the greater the maximum height of ESF irregularities responsible for the radar backscatter, the greater the decorrelation is of the spaced receiver scintillation signals, indicating greater turbulence. The relationship of the maximum spectral width derived from the radar observations and CI also supports this result.

  8. The Marine Corps Civil Military Operations (CMO) Capability: Inadequate for Current and Future Irregular Environments

    Science.gov (United States)

    2011-05-02

    the 2011 National Military Strategy contend and numerous analysts posit, that the United States will continue to prosecute irregular warfare or a...think tank reports, and the ruminations of various luminaries that the United States will be involved in inegular wmfare throughout the remainder of

  9. Short-term magnetic field alignment variations of equatorial ionospheric irregularities

    International Nuclear Information System (INIS)

    Johnson, A.L.

    1988-01-01

    The ionospheric irregularities that cause equatorial scintillation are elongated along the north-south magnetic field lines. During a 1981 field campaign at Ascension Island, 250-MHz receivers were spaced from 300 m to 1.6 km along the field lines, and the signals received from the Marisat satellite were cross correlated. Data collected during eight nights of fading showed a linear relationship between fading rate and cross correlation. The alignment of the antennas was adjusted to give a zero time lag between the widely spaced receivers with a measurement accuracy of 0.03 s. Since the average irregularity velocity was 125 m/s, this time accuracy translated to an angular measurement accuracy of 0.1 deg. During a 4-hour period of nightly fading, occasional differences in time of arrival were noted that corresponded to a tilt in the north-south alignment of + or - 1 deg. Data from several nights of fading were analyzed, and each night exhibited the same variance in the north-south irregularity alignment. It is postulated that the shift in the measured peak correlation may have been caused by patches of irregularities at different altitudes where the magnetic field lines have a slightly different direction. 13 references

  10. The governance of international migration in Turkey and Morocco: Irregular migrants’ access to right to stay

    NARCIS (Netherlands)

    Üstübici Önay, A.E.

    2015-01-01

    This thesis analyses migrant experiences of illegality in Turkey and Morocco by taking into account how both countries responded to increasing pressure by the European Union to govern irregular migration within their territories. In dialogue with literatures on the legal production of migrant

  11. A Strategy of Attrition through Enforcement: The Unmaking of Irregular Migration in Malaysia

    OpenAIRE

    Choo Chin Low

    2017-01-01

    This article reviews Malaysia's attempt to achieve zero migration irregularity by focusing on workplace enforcement, and examines how Malaysia's migration control has become a struggle between the state and employers. Applying the framework of "enforcement through attrition", this research examines three newly introduced principles governing workplace enforcement: employer sanctions, the Strict Liability Principle, and the Employers' Mandatory Commitment. The shift to employers in Malaysia's ...

  12. Using Localised Quadratic Functions on an Irregular Grid for Pricing High-Dimensional American Options

    NARCIS (Netherlands)

    Berridge, S.J.; Schumacher, J.M.

    2004-01-01

    We propose a method for pricing high-dimensional American options on an irregular grid; the method involves using quadratic functions to approximate the local effect of the Black-Scholes operator.Once such an approximation is known, one can solve the pricing problem by time stepping in an explicit

  13. On total irregularity strength of caterpillar graphs with two leaves on each internal vertex

    Science.gov (United States)

    Rosyida, I.; Widodo; Indriati, D.

    2018-04-01

    Let G(V, E) be a graph. A function f from V(G)\\cup E(G) to the set {1, 2, …, k} is said to be a totally irregular total k-labeling of G if the weights of any two different vertices x and y in V (G) satisfy {w}f(x)\

  14. Modelling the Cost Performance of a Given Logistics Network Operating Under Regular and Irregular Conditions

    NARCIS (Netherlands)

    Janic, M.

    2009-01-01

    This paper develops an analytical model for the assessment of the cost performance of a given logistics network operating under regular and irregular (disruptive) conditions. In addition, the paper aims to carry out a sensitivity analysis of this cost with respect to changes of the most influencing

  15. Special Operations, Irregular Warfare, and Operational Art: A Theory of Special Operations

    Science.gov (United States)

    2013-12-10

    is mostly but not wholly a land phenomenon. Naval forces have combatted maritime irregulars such as pirates for millennia, for example see: Plutarch ...SW2502SocialMediaAndUW.html (accessed June 15, 2013). Plaster, John L. SOG: Secret Wars of America’s Commandos in Vietnam. New York: Simon & Schuster, 1997. Plutarch

  16. A Novel Energy Yields Calculation Method for Irregular Wind Farm Layout

    DEFF Research Database (Denmark)

    Hou, Peng; Hu, Weihao; Soltani, Mohsen

    2015-01-01

    Due to the increasing size of offshore wind farm, the impact of the wake effect on energy yields become more and more evident. The Seafloor topography would limit the layout of the wind farm so that irregular layout is usually adopted inlarge scale offshore wind farm. However, the calculation...

  17. Coherent and intermittent ensemble oscillations emerge from networks of irregular spiking neurons.

    Science.gov (United States)

    Hoseini, Mahmood S; Wessel, Ralf

    2016-01-01

    Local field potential (LFP) recordings from spatially distant cortical circuits reveal episodes of coherent gamma oscillations that are intermittent, and of variable peak frequency and duration. Concurrently, single neuron spiking remains largely irregular and of low rate. The underlying potential mechanisms of this emergent network activity have long been debated. Here we reproduce such intermittent ensemble oscillations in a model network, consisting of excitatory and inhibitory model neurons with the characteristics of regular-spiking (RS) pyramidal neurons, and fast-spiking (FS) and low-threshold spiking (LTS) interneurons. We find that fluctuations in the external inputs trigger reciprocally connected and irregularly spiking RS and FS neurons in episodes of ensemble oscillations, which are terminated by the recruitment of the LTS population with concurrent accumulation of inhibitory conductance in both RS and FS neurons. The model qualitatively reproduces experimentally observed phase drift, oscillation episode duration distributions, variation in the peak frequency, and the concurrent irregular single-neuron spiking at low rate. Furthermore, consistent with previous experimental studies using optogenetic manipulation, periodic activation of FS, but not RS, model neurons causes enhancement of gamma oscillations. In addition, increasing the coupling between two model networks from low to high reveals a transition from independent intermittent oscillations to coherent intermittent oscillations. In conclusion, the model network suggests biologically plausible mechanisms for the generation of episodes of coherent intermittent ensemble oscillations with irregular spiking neurons in cortical circuits. Copyright © 2016 the American Physiological Society.

  18. Eddy current heating of irregularly shaped plates by slow ramped fields

    International Nuclear Information System (INIS)

    Dresner, L.

    1979-01-01

    Theorems are presented for estimating eddy current heating of irregularly shaped plates by a perpendicular ramped field. The theorems, which are derived from two complementary variational principles, give upper and lower bounds to the eddy current heating. Illustrative results are given for rectangles, isosceles triangles, sectors of circular annuli, rhombuses, and L-shaped plates. A comparison is made with earlier work

  19. Metaphyseal cortical irregularities in children: A new perspective on a multi-focal growth variant

    Energy Technology Data Exchange (ETDEWEB)

    Keats, T.E.; Joyce, J.M.

    1984-07-01

    The occurrence of metaphyseal cortical irregularities in adolescents in many different bones indicates a commonality of these lesions as a variation of normal growth, rather than a stress or avulsive by-product. The histologically recognized incomplete nature of the metaphysical cortex in children offers an attractive explanation for this phenomenon.

  20. An Irregular Grid Approach for Pricing High-Dimensional American Options

    NARCIS (Netherlands)

    Berridge, S.J.; Schumacher, J.M.

    2004-01-01

    We propose and test a new method for pricing American options in a high-dimensional setting.The method is centred around the approximation of the associated complementarity problem on an irregular grid.We approximate the partial differential operator on this grid by appealing to the SDE

  1. Videokymography. Imaging and quantification of regular and irregular vocal fold vibrations

    NARCIS (Netherlands)

    Schutte, HK; Svec, JG; Sram, F; McCafferty, G; Coman, W; Carroll, R

    1996-01-01

    A newly developed imaging technique makes it possible to observe the vocal fold vibration pattern also under unstable conditions. In contrast to stroboscopy, which strongly relies on the regularity of the vibration under study videokymography enables the study of irregular patterns as well. The

  2. Spherical and irregular aberrations are important for the optimal performance of the human eye

    NARCIS (Netherlands)

    Nio, YK; Jansonius, NM; Fidler, [No Value; Geraghty, E; Norrby, S; Kooijman, AC

    Contrast sensitivity measured psychophysically at different levels of defocus can be used to evaluate the eye optics. Possible parameters of spherical and irregular aberrations, e.g, relative modulation transfer (RMT), myopic shift, and depth of focus, can be determined from these measurements. The

  3. Health care for irregular migrants: pragmatism across Europe: a qualitative study

    NARCIS (Netherlands)

    Dauvrin, M.; Lorant, V.; Sandhu, S.; Devillé, W.; Dia, H.; Dias, S.; Gaddini, A.; Ioannidis, E.; Jensen, N.K.; Kluge, U.; Mertaniemi, R.; Puigpinós i Riera, R.; Sárváry, A.; Straßmayr, C.; Stankunas, M.; Soares, J.J.F.; Welbel, M.; Priebe, S.

    2012-01-01

    Background Health services in Europe face the challenge of delivering care to a heterogeneous group of irregular migrants (IM). There is little empirical evidence on how health professionals cope with this challenge. This study explores the experiences of health professionals providing care to IM in

  4. Gait Characteristics Associated with Trip-Induced Falls on Level and Sloped Irregular Surfaces

    Directory of Open Access Journals (Sweden)

    Andrew Merryweather

    2011-11-01

    Full Text Available Same level falls continue to contribute to an alarming number of slip/trip/fall injuries in the mining workforce. The objective of this study was to investigate how walking on different surface types and transverse slopes influences gait parameters that may be associated with a trip event. Gait analysis was performed for ten subjects on two orientations (level and sloped on smooth, hard surface (control and irregular (gravel, larger rocks surfaces. Walking on irregular surfaces significantly increased toe clearance compared to walking on the smooth surface. There was a significant (p < 0.05 decrease in cadence (steps/min, stride length (m, and speed (m/s from control to gravel to larger rocks. Significant changes in external rotation and increased knee flexion while walking on irregular surfaces were observed. Toe and heel clearance requirements increased on irregular surfaces, which may provide an explanation for trip-induced falls; however, the gait alterations observed in the experienced workers used as subjects would likely improve stability and recovery from a trip.

  5. Modalities of Tonometry and their Accuracy with Respect to Corneal Thickness and Irregularities

    Directory of Open Access Journals (Sweden)

    Carlos Gustavo V. De Moraes

    2008-01-01

    Each of the many different commercially available tonometers has specific advantages and disadvantages. New non-invasive technologies are getting closer to a precise estimation of the true IOP. However, among all tonometers, none is highly accurate when both corneal thickness and surface irregularities are present. Fifty years after its development, Goldmann tonometry remains the gold standard to which all other devices are compared.

  6. The normal squamocolumnar junction is circumferentially even and minimal irregularities are manifestations of gastroesophageal acid reflux.

    Science.gov (United States)

    Guerrero Garcia Hall, Mats; Wenner, Jörgen; Öberg, Stefan

    2017-03-01

    The macroscopic appearance of the normal squamocolumnar junction (SCJ) is often described as serrated with short projections of columnar mucosa that extend into the esophagus. As studies of the normal SCJ are sparse, the aim of this study was to test the hypothesis that the normal SCJ is even and that irregularities are manifestations of acid reflux. Fifty asymptomatic subjects and 149 patients with symptoms suggestive of gastroesophageal reflux disease underwent endoscopy and 48-h pH monitoring with a pH electrode positioned immediately above the SCJ. The shape of the SCJ was assessed according to the Z-line appearance classification and correlated with clinical characteristics and the degree of esophageal acid exposure in the most distal esophagus. Even SCJs without irregularities were significantly more common in asymptomatic subjects compared with patients (50% versus 10%, p acid exposure in individuals with an even SCJ was within normal limits. With increasing degree of irregularity of the SCJ, the frequency and duration of reflux episodes, the degree of distal esophageal acid exposure, and the prevalence of abnormal acid exposure increased progressively and significantly. The shape of the normal SCJ is even and also minimal irregularities are a consequence of acid reflux, likely due to the formation of small areas of metaplastic columnar mucosa.

  7. Meal irregularity and cardiometabolic consequences: results from observational and intervention studies

    NARCIS (Netherlands)

    Pot, G.K.; Almoosawi, S; Stephen, AM

    2016-01-01

    Studying irregular meal patterns fits in with the latest research focusing not only on what people eat but also when they eat, also called chrono-nutrition. Chrono-nutrition involves studying the impact of nutrition on metabolism via circadian patterns, including three aspects of time:

  8. Irregular wave functions of a hydrogen atom in a uniform magnetic field

    Science.gov (United States)

    Wintgen, D.; Hoenig, A.

    1989-01-01

    The highly excited irregular wave functions of a hydrogen atom in a uniform magnetic field are investigated analytically, with wave function scarring by periodic orbits considered quantitatively. The results obtained confirm that the contributions of closed classical orbits to the spatial wave functions vanish in the semiclassical limit. Their disappearance, however, is slow. This discussion is illustrated by numerical examples.

  9. Mental health care for irregular migrants in Europe: Barriers and how they are overcome

    NARCIS (Netherlands)

    Straßmayr, Christa; Matanov, Aleksandra; Priebe, Stefan; Barros, Henrique; Canavan, Reamonn; Díaz-Olalla, José Manuel; Gabor, Edina; Gaddini, Andrea; Greacen, Tim; Holcnerová, Petra; Kluge, Ulrike; Welbel, Marta; Nicaise, Pablo; Schene, Aart H.; Soares, Joaquim J. F.; Katschnig, Heinz

    2012-01-01

    Background: Irregular migrants (IMs) are exposed to a wide range of risk factors for developing mental health problems. However, little is known about whether and how they receive mental health care across European countries. The aims of this study were (1) to identify barriers to mental health care

  10. Research on making reactor buildings of irregular plan and elevation forms aseismatic

    International Nuclear Information System (INIS)

    Okawa, Izuru; Yamauchi, Yasuyuki

    1997-01-01

    The necessity of pursuing the possibility of irregular form buildings as the condition of location for construction is limited, and the rational and economical arrangement of equipment and piping is considered. In order to know the effect that irregular forms exert to the aseismatic ability of buildings, it is indispensable to develop the program for precision three-dimensional elastoplastic analysis at the time of earthquakes. As the means of solving the problem, the introduction of seismic insulation structure is conceivable. The investigation of seismic insulator and its modeling and the analysis of earthquake response were carried out, and the irregular form and the effect of seismic insulation were investigated, and the results of vibration test using test specimens were summarized. The concrete items of investigation were the characteristics of input earthquake motion, the techniques of analysis, the parametric study taking the input and various characteristics of buildings in consideration, and the synthetic assessment. The vibration table experiment and the static loading experiment for the purpose of grasping the response behavior in the case of irregular form of wall type and seismic insulation type structures were carried out, and the results are reported. (K.I.)

  11. Pricing and hedging high-dimensional American options : an irregular grid approach

    NARCIS (Netherlands)

    Berridge, S.; Schumacher, H.

    2002-01-01

    We propose and test a new method for pricing American options in a high dimensional setting. The method is centred around the approximation of the associated variational inequality on an irregular grid. We approximate the partial differential operator on this grid by appealing to the SDE

  12. PERIODIC ORBIT FAMILIES IN THE GRAVITATIONAL FIELD OF IRREGULAR-SHAPED BODIES

    International Nuclear Information System (INIS)

    Jiang, Yu; Baoyin, Hexi

    2016-01-01

    The discovery of binary and triple asteroids in addition to the execution of space missions to minor celestial bodies in the past several years have focused increasing attention on periodic orbits around irregular-shaped celestial bodies. In the present work, we adopt a polyhedron shape model for providing an accurate representation of irregular-shaped bodies and employ the model to calculate their corresponding gravitational and effective potentials. We also investigate the characteristics of periodic orbit families and the continuation of periodic orbits. We prove a fact, which provides a conserved quantity that permits restricting the number of periodic orbits in a fixed energy curved surface about an irregular-shaped body. The collisions of Floquet multipliers are maintained during the continuation of periodic orbits around the comet 1P/Halley. Multiple bifurcations in the periodic orbit families about irregular-shaped bodies are also discussed. Three bifurcations in the periodic orbit family have been found around the asteroid 216 Kleopatra, which include two real saddle bifurcations and one period-doubling bifurcation.

  13. Young Japanese college students with dysmenorrhea have high frequency of irregular menstruation and premenstrual symptoms.

    Science.gov (United States)

    Fujiwara, Tomoko; Nakata, Rieko

    2007-01-01

    In this study, to estimate the current status of young women with menstrual disorders, the relation among dysmenorrhea, irregular menstruation and premenstrual symptoms was investigated by a questionnaire. Subjects ranging from 18 to 20 years old were recruited from 522 female students at Ashiya College in Japan. The intensity of dysmenorrhea was classified into 3 grades (score 1, not requiring analgesic; score 2, painful, requiring analgesic; score 3, painful, not relieved by analgesic). All participants were further divided into subsequent groups as having premenstrual symptoms or not and those having regular or irregular menstruation. Dysmenorrhea scores in the students with premenstrual symptoms or irregular menstruation were significantly higher than those without these symptoms (1.66+/-0.66 vs 1.41+/-0.59; 1.62+/-0.68 vs 1.49+/-0.61, respectively). There was no significant relation in the incidence between premenstrual symptoms and irregular menstruation. These findings suggest that considerable numbers of young women with dysmenorrhea are associated with premenstrual symptoms.

  14. Influence of the Wenchuan earthquake on self-reported irregular menstrual cycles in surviving women.

    Science.gov (United States)

    Li, Xiao-Hong; Qin, Lang; Hu, Han; Luo, Shan; Li, Lei; Fan, Wei; Xiao, Zhun; Li, Ying-Xing; Li, Shang-Wei

    2011-09-01

    To explore the influence of stress induced by the Wenchuan earthquake on the menstrual cycles of surviving women. Self-reports of the menstrual cycles of 473 women that survived the Wenchuan earthquake were analyzed. Menstrual regularity was defined as menses between 21 and 35 days long. The death of a child or the loss of property and social resources was verified for all surviving women. The severity of these losses was assessed and graded as high, little, and none. About 21% of the study participants reported that their menstrual cycles became irregular after the Wenchuan earthquake, and this percentage was significantly higher than before the earthquake (6%, p irregularity after the earthquake. Association analyses showed that some stressors of the Wenchuan earthquake were strongly associated with self-reports of menstrual irregularity, including the loss of children (RR: 1.58; 95% CI: 1.09, 2.28), large amounts of property (RR: 1.49; 95% CI: 1.03, 2.15), social resources (RR: 1.34; 95% CI: 1.00, 1.80) and the hormonal contraception use (RR: 1.62; 95% CI: 1.21, 1.83). Self-reported menstrual irregularity is common in women that survived the Wenchuan earthquake, especially in those who lost children, large amounts of property and social resources.

  15. Effects of irregular-shift work and physical activity on cardiovascular risk factors in truck drivers

    Directory of Open Access Journals (Sweden)

    Elaine Cristina Marqueze

    2013-06-01

    Full Text Available OBJECTIVE: To analyze the putative effect of type of shift and its interaction with leisure-time physical activity on cardiovascular risk factors in truck drivers. METHODS: A cross-sectional study was undertaken on 57 male truck drivers working at a transportation company, of whom 31 worked irregular shifts and 26 worked on the day-shift. Participants recorded their physical activity using the International Physical Activity Questionnaire along with measurements of blood pressure, body mass index and waist-hip ratio. Participants also provided a fasting blood sample for analysis of lipid-related outcomes. Data were analyzed using a factorial model which was covariate-controlled for age, smoking, work demand, control at work and social support. RESULTS: Most of the irregular-shift and day-shift workers worked more than 8 hours per day (67.7% and 73.1%, respectively. The mean duration of experience working the irregular schedule was 15.7 years. Day-shift workers had never engaged in irregular-shift work and had been working as a truck driver for 10.8 years on average. The irregular-shift drivers had lower work demand but less control compared to day-shift drivers (p < 0.05. Moderately-active irregular-shift workers had higher systolic and diastolic arterial pressures (143.7 and 93.2 mmHg, respectively than moderately-active day-shift workers (116 and 73.3 mmHg, respectively (p < 0.05 as well as higher total cholesterol concentrations (232.1 and 145 mg/dl, respectively (p = 0.01. Irrespective of their physical activity, irregular-shift drivers had higher total cholesterol and LDL-cholesterol concentrations (211.8 and 135.7 mg/dl, respectively than day-shift workers (161.9 and 96.7 mg/dl, respectively (ANCOVA, p < 0.05. CONCLUSIONS: Truck drivers are exposed to cardiovascular risk factors due to the characteristics of the job, such as high work demand, long working hours and time in this profession, regardless of shift type or leisure-time physical

  16. Effects of irregular two-dimensional and three-dimensional surface roughness in turbulent channel flows

    International Nuclear Information System (INIS)

    De Marchis, M.; Napoli, E.

    2012-01-01

    Highlights: ► 3D irregular rough surfaces produce higher effects than those observed over 2D. ► Effective slope is a geometrical parameter representative of the roughness effects. ► 3D rough surfaces enhance the turbulence isotropization. ► 2D and 3D irregular roughness partially support the wall similarity. ► Irregular rough surfaces shear some features with regular rough walls. - Abstract: Wall-resolved Large Eddy Simulation of fully developed turbulent channel flows over two different rough surfaces is performed to investigate on the effects of irregular 2D and 3D roughness on the turbulence. The two geometries are obtained through the superimposition of sinusoidal functions having random amplitudes and different wave lengths. In the 2D configuration the irregular shape in the longitudinal direction is replicated in the transverse one, while in the 3D case the sinusoidal functions are generated both in streamwise and spanwise directions. Both channel walls are roughened in such a way as to obtain surfaces with statistically equivalent roughness height, but different shapes. In order to compare the turbulence properties over the two rough walls and to analyse the differences with a smooth wall, the simulations are performed at the same Reynolds number Re τ = 395. The same mean roughness height h = 0.05δ (δ the half channel height) is used for the rough walls. The roughness function obtained with the 3D roughness is larger than in the 2D case, although the two walls share the same mean height. Thus, the considered irregular 3D roughness is more effective in reducing the flow velocity with respect to the 2D roughness, coherently with the literature results that identified a clear dependence of the roughness function on the effective slope (see ), higher in the generated 3D rough wall. The analysis of higher-order statistics shows that the effects of the roughness, independently on its two- or three-dimensional shape, are mainly confined in the inner

  17. The effect of earthquake on architecture geometry with non-parallel system irregularity configuration

    Science.gov (United States)

    Teddy, Livian; Hardiman, Gagoek; Nuroji; Tudjono, Sri

    2017-12-01

    Indonesia is an area prone to earthquake that may cause casualties and damage to buildings. The fatalities or the injured are not largely caused by the earthquake, but by building collapse. The collapse of the building is resulted from the building behaviour against the earthquake, and it depends on many factors, such as architectural design, geometry configuration of structural elements in horizontal and vertical plans, earthquake zone, geographical location (distance to earthquake center), soil type, material quality, and construction quality. One of the geometry configurations that may lead to the collapse of the building is irregular configuration of non-parallel system. In accordance with FEMA-451B, irregular configuration in non-parallel system is defined to have existed if the vertical lateral force-retaining elements are neither parallel nor symmetric with main orthogonal axes of the earthquake-retaining axis system. Such configuration may lead to torque, diagonal translation and local damage to buildings. It does not mean that non-parallel irregular configuration should not be formed on architectural design; however the designer must know the consequence of earthquake behaviour against buildings with irregular configuration of non-parallel system. The present research has the objective to identify earthquake behaviour in architectural geometry with irregular configuration of non-parallel system. The present research was quantitative with simulation experimental method. It consisted of 5 models, where architectural data and model structure data were inputted and analyzed using the software SAP2000 in order to find out its performance, and ETAB2015 to determine the eccentricity occurred. The output of the software analysis was tabulated, graphed, compared and analyzed with relevant theories. For areas of strong earthquake zones, avoid designing buildings which wholly form irregular configuration of non-parallel system. If it is inevitable to design a

  18. Refraction traveltime tomography based on damped wave equation for irregular topographic model

    Science.gov (United States)

    Park, Yunhui; Pyun, Sukjoon

    2018-03-01

    Land seismic data generally have time-static issues due to irregular topography and weathered layers at shallow depths. Unless the time static is handled appropriately, interpretation of the subsurface structures can be easily distorted. Therefore, static corrections are commonly applied to land seismic data. The near-surface velocity, which is required for static corrections, can be inferred from first-arrival traveltime tomography, which must consider the irregular topography, as the land seismic data are generally obtained in irregular topography. This paper proposes a refraction traveltime tomography technique that is applicable to an irregular topographic model. This technique uses unstructured meshes to express an irregular topography, and traveltimes calculated from the frequency-domain damped wavefields using the finite element method. The diagonal elements of the approximate Hessian matrix were adopted for preconditioning, and the principle of reciprocity was introduced to efficiently calculate the Fréchet derivative. We also included regularization to resolve the ill-posed inverse problem, and used the nonlinear conjugate gradient method to solve the inverse problem. As the damped wavefields were used, there were no issues associated with artificial reflections caused by unstructured meshes. In addition, the shadow zone problem could be circumvented because this method is based on the exact wave equation, which does not require a high-frequency assumption. Furthermore, the proposed method was both robust to an initial velocity model and efficient compared to full wavefield inversions. Through synthetic and field data examples, our method was shown to successfully reconstruct shallow velocity structures. To verify our method, static corrections were roughly applied to the field data using the estimated near-surface velocity. By comparing common shot gathers and stack sections with and without static corrections, we confirmed that the proposed tomography

  19. Validation studies of nursing diagnoses in neonatology

    Directory of Open Access Journals (Sweden)

    Pavlína Rabasová

    2016-03-01

    Full Text Available Aim: The objective of the review was the analysis of Czech and foreign literature sources and professional periodicals to obtain a relevant comprehensive overview of validation studies of nursing diagnoses in neonatology. Design: Review. Methods: The selection criterion was studies concerning the validation of nursing diagnoses in neonatology. To obtain data from relevant sources, the licensed professional databases EBSCO, Web of Science and Scopus were utilized. The search criteria were: date of publication - unlimited; academic periodicals - full text; peer-reviewed periodicals; search language - English, Czech and Slovak. Results: A total of 788 studies were found. Only 5 studies were eligible for content analysis, dealing specifically with validation of nursing diagnoses in neonatology. The analysis of the retrieved studies suggests that authors are most often concerned with identifying the defining characteristics of nursing diagnoses applicable to both the mother (parents and the newborn. The diagnoses were validated in the domains Role Relationship; Coping/Stress tolerance; Activity/Rest, and Elimination and Exchange. Diagnoses represented were from the field of dysfunctional physical needs as well as the field of psychosocial and spiritual needs. The diagnoses were as follows: Parental role conflict (00064; Impaired parenting (00056; Grieving (00136; Ineffective breathing pattern (00032; Impaired gas exchange (00030; and Impaired spontaneous ventilation (00033. Conclusion: Validation studies enable effective planning of interventions with measurable results and support clinical nursing practice.

  20. The Consistency Between Clinical and Electrophysiological Diagnoses

    Directory of Open Access Journals (Sweden)

    Esra E. Okuyucu

    2009-09-01

    Full Text Available OBJECTIVE: The aim of this study was to provide information concerning the impact of electrophysiological tests in the clinical management and diagnosis of patients, and to evaluate the consistency between referring clinical diagnoses and electrophysiological diagnoses. METHODS: The study included 957 patients referred to the electroneuromyography (ENMG laboratory from different clinics with different clinical diagnoses in 2008. Demographic data, referring clinical diagnoses, the clinics where the requests wanted, and diagnoses after ENMG testing were recorded and statistically evaluated. RESULTS: In all, 957 patients [644 (67.3% female and 313 (32.7% male] were included in the study. Mean age of the patients was 45.40 ± 14.54 years. ENMG requests were made by different specialists; 578 (60.4% patients were referred by neurologists, 122 (12.8% by orthopedics, 140 (14.6% by neurosurgeons, and 117 (12.2% by physical treatment and rehabilitation departments. According to the results of ENMG testing, 513 (53.6% patients’ referrals were related to their referral diagnosis, whereas 397 (41.5% patients had normal ENMG test results, and 47 (4.9% patients had a diagnosis that differed from the referring diagnosis. Among the relation between the referral diagnosis and electrophysiological diagnosis according to the clinics where the requests were made, there was no statistical difference (p= 0.794, but there were statistically significant differences between the support of different clinical diagnoses, such as carpal tunnel syndrome, polyneuropathy, radiculopathy-plexopathy, entrapment neuropathy, and myopathy based on ENMG test results (p< 0.001. CONCLUSION: ENMG is a frequently used neurological examination. As such, referrals for ENMG can be made to either support the referring diagnosis or to exclude other diagnoses. This may explain the inconsistency between clinical referring diagnoses and diagnoses following ENMG

  1. Influence of initial stress, irregularity and heterogeneity on Love-type wave propagation in double pre-stressed irregular layers lying over a pre-stressed half-space

    Science.gov (United States)

    Singh, Abhishek Kumar; Das, Amrita; Parween, Zeenat; Chattopadhyay, Amares

    2015-10-01

    The present paper deals with the propagation of Love-type wave in an initially stressed irregular vertically heterogeneous layer lying over an initially stressed isotropic layer and an initially stressed isotropic half-space. Two different types of irregularities, viz., rectangular and parabolic, are considered at the interface of uppermost initially stressed heterogeneous layer and intermediate initially stressed isotropic layer. Dispersion equations are obtained in closed form for both cases of irregularities, distinctly. The effect of size and shape of irregularity, horizontal compressive initial stress, horizontal tensile initial stress, heterogeneity of the uppermost layer and width ratio of the layers on phase velocity of Love-type wave are the major highlights of the study. Comparative study has been made to identify the effects of different shapes of irregularity, presence of heterogeneity and initial stresses. Numerical computations have been carried out and depicted by means of graphs for the present study.

  2. Questioning the Homogenization of Irregular Migrants in Educational Policy: From (Il)Legal Residence to Inclusive Education

    Science.gov (United States)

    Hemelsoet, Elias

    2011-01-01

    In this article Elias Hemelsoet questions the way irregular migrants are approached in educational policymaking. In most cases, estimations of the number of irregular migrants serve--despite large methodological problems--as a starting point for policymaking. Given the very diverse composition of this group of people, the question is whether…

  3. Exploring Individual Differences in Irregular Word Recognition among Children with Early-Emerging and Late-Emerging Word Reading Difficulty

    Science.gov (United States)

    Steacy, Laura M.; Kearns, Devin M.; Gilbert, Jennifer K.; Compton, Donald L.; Cho, Eunsoo; Lindstrom, Esther R.; Collins, Alyson A.

    2017-01-01

    Models of irregular word reading that take into account both child- and word-level predictors have not been evaluated in typically developing children and children with reading difficulty (RD). The purpose of the present study was to model individual differences in irregular word reading ability among 5th grade children (N = 170), oversampled for…

  4. Study of midlatitude ionospheric irregularities and E- and F-region coupling based on rocket and radar observations from Japan

    Science.gov (United States)

    Yamamoto, M.

    2015-12-01

    We have been studying ionspheric irregularities in mid-latitude region by using radars, sounding rockets, etc. The mid-latitude ionosphere was considered much stable than those in the equatorial or polar region in the past, but our studies for years have revealed that there are much active variabilities. We found variety of wave-like structures that are specific in the mid-latitudes. One of the phenomena is quasi-periodic echoes (QP echoes) first observed by the MU radar that reflects horizontal plasma-density structures associated to sporadic-E layers. Another phenomenon is medium-scale traveling ionospheric disturbance (MSTID) in the F-region. In the generation mechanism we think that Ionospheric E- and F-region coupling process is important. In this presentation, we will discuss nature of mid-latitude ionosphere based on our observations; the MU radar, sounding rocket campaigns of SEEK-1/2, and recent MSTID rocket experiment from JAXA Uchinoura Space Center in July 2013.

  5. Observations of the F-region ionospheric irregularities in the South American sector during the October 2003 "Halloween Storms"

    Directory of Open Access Journals (Sweden)

    Y. Sahai

    2009-12-01

    Full Text Available The response of the ionospheric F-region in the South American sector during the super geomagnetic storms on 29 and 30 October 2003 is studied in the present investigation. In this paper, we present ionospheric sounding observations during the period 29–31 October 2003 obtained at Palmas (a near equatorial location and Sao Jose dos Campos (a location under the southern crest of the equatorial ionospheric anomaly, Brazil, along with observations during the period 27–31 October 2003 from a chain of GPS stations covering the South American sector from Imperatriz, Brazil, to Rio Grande, Argentina. Also, complementary observations that include sequences of all-sky images of the OI 777.4 and 630.0 nm emissions observed at El Leoncito, Argentina, on the nights of 28–29 (geomagnetically quiet night and 29–30 (geomagnetically disturbed night October 2003, and ion densities observed in the South American sector by the DMSP F13, F14 and F15 satellites orbiting at about 800 km on 29 and 30 October 2003 are presented. In addition, global TEC maps derived from GPS observations collected from the global GPS network of International GPS Service (IGS are presented, showing widespread and drastic TEC changes during the different phases of the geomagnetic disturbances. The observations indicate that the equatorial ionospheric irregularities or plasma bubbles extend to the Argentinean station Rawson (geom. Lat. 33.1° S and map at the magnetic equator at an altitude of about 2500 km.

  6. Artificial E-region field-aligned plasma irregularities generated at pump frequencies near the second electron gyroharmonic

    Directory of Open Access Journals (Sweden)

    D. L. Hysell

    2009-07-01

    Full Text Available E region ionospheric modification experiments have been performed at HAARP using pump frequencies about 50 kHz above and below the second electron gyroharmonic frequency. Artificial E region field-aligned plasma density irregularities (FAIs were created and observed using the imaging coherent scatter radar near Homer, Alaska. Echoes from FAIs generated with pump frequencies above and below 2Ωe did not appear to differ significantly in experiments conducted on summer afternoons in 2008, and the resonance instability seemed to be at work in either case. We argue that upper hybrid wave trapping and resonance instability at pump frequencies below the second electron gyroharmonic frequency are permitted theoretically when the effects of finite parallel wavenumbers are considered. Echoes from a sporadic E layer were observed to be somewhat weaker when the pump frequency was 50 kHz below the second electron gyroharmonic frequency. This may indicate that finite parallel wavenumbers are inconsistent with wave trapping in thin sporadic E ionization layers.

  7. Artificial E-region field-aligned plasma irregularities generated at pump frequencies near the second electron gyroharmonic

    Directory of Open Access Journals (Sweden)

    D. L. Hysell

    2009-07-01

    Full Text Available E region ionospheric modification experiments have been performed at HAARP using pump frequencies about 50 kHz above and below the second electron gyroharmonic frequency. Artificial E region field-aligned plasma density irregularities (FAIs were created and observed using the imaging coherent scatter radar near Homer, Alaska. Echoes from FAIs generated with pump frequencies above and below 2Ωe did not appear to differ significantly in experiments conducted on summer afternoons in 2008, and the resonance instability seemed to be at work in either case. We argue that upper hybrid wave trapping and resonance instability at pump frequencies below the second electron gyroharmonic frequency are permitted theoretically when the effects of finite parallel wavenumbers are considered. Echoes from a sporadic E layer were observed to be somewhat weaker when the pump frequency was 50 kHz below the second electron gyroharmonic frequency. This may indicate that finite parallel wavenumbers are inconsistent with wave trapping in thin sporadic E ionization layers.

  8. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... options further? Fertility Preservation - Where Does It Fit? Options for Fertility Preservation The following diagram gives a brief description of fertility preservation options available to children diagnosed with cancer before and ...

  9. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... Not an option if there is a high risk of ovarian metastases. Discuss with your doctor. b ... an IRB . Resources For more information about infertility risk and fertility preservation options for children diagnosed with ...

  10. How Do Health Care Providers Diagnose Vaginitis?

    Science.gov (United States)

    ... used to diagnose vaginitis. 1 Centers for Disease Control and Prevention. (2010). Self-study STD ... Halvorson New Chief of Gynecologic Health and Disease Branch Division of Epidemiology, Statistics, ...

  11. Fertility Preservation for Children Diagnosed with Cancer

    Science.gov (United States)

    ... Skip to main content SaveMyFertility An Online Fertility Preservation Toolkit for Patients and Their Providers Open menu ... with Cancer You are here Home » Patients Fertility Preservation for Children Diagnosed with Cancer Fertility Preservation for ...

  12. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... for Children Diagnosed with Cancer Ask Your Doctor Information for Patients Many adult survivors of childhood cancer ... study approved by an IRB . Resources For more information about infertility risk and fertility preservation options for ...

  13. ADHD: the impact when not diagnosed

    OpenAIRE

    Souza,Isabella de; Mattos,Paulo; Pina,Camila; Fortes,Didia

    2008-01-01

    ADHD is a highly prevalent disorder in childhood with social, academic and familial difficulties when not diagnosed and treated correctly. The aim of this case report is to demonstrate the impairment of ADHD among generations of the same family.

  14. Fertility Preservation for Children Diagnosed with Cancer

    Medline Plus

    Full Text Available ... be fertility preservation options available and having your child see a reproductive specialist in a timely manner ... there are options for preserving fertility in your child diagnosed with cancer. You may be focused on ...

  15. Irregular incentives

    International Nuclear Information System (INIS)

    Cicchetti, M.A.

    1993-01-01

    Public utility regulation lacks a formal proxy for the economic profits that can be earned in an effectively competitive market if a firm is efficient or innovative. After all, public utility regulation operated on cost-plus basis. If a utility is efficient or innovative and lowers its costs, its typical reward is to have its rates reduced. This is a perverse incentive to motivate a utility to produce at the most efficient level. In addition, since regulation operates on this cost-plus basis, a utility can increase its net income, all other things being equal, by overinvesting in (or open-quotes gold-platingclose quotes) its system, another perverse incentive. Recognizing these flaws of regulation, academicians, utility executives, regulators, and legislators have tried over the last several years to implement incentive regulation plans that correct such perverse incentives. However, under many of the earnings-sharing or price-regulation incentive plans, the rewards for efficient production are not tied directly to measures under a company's control. In fact, such plans could prove highly detrimental to ratepayers and competitors of the regulated company and its affiliates. An incentive regulation plan that ties an appropriate reward for efficient production to specific efficiency gains is a better proxy of an effectively competitive environment. What's more, it is superior to an incentive plan that rewards circumstances beyond the company's control or self-serving manipulation. This is particularly true if no earnings cap is associated with the reward for efficiency. Rewards for efficient production should be tied to specific actions. A suitable incentive plan does not preclude appropriately derived flexible prices for certain products or services where warranted

  16. At få en diagnose

    DEFF Research Database (Denmark)

    Olesen, Birgitte Ravn; Jansbøl, Kirsten

    I dette hæfte ligger fokus på døvblindblevnes fortællinger om at have et handicap uden at kende sin diagnose og om at håndtre at få diagnosen RP eller Usher syndrom. Det er karakteristisk for fortællingerne, at det har stor betydning - hvornår i livet, man får sin diagnose - under hvilke...

  17. Challenges in diagnosing tuberculosis in children

    DEFF Research Database (Denmark)

    Rahman, Nadia; Pedersen, Karin Kæreby; Rosenfeldt, Vibeke

    2012-01-01

    Clinical investigations of childhood tuberculosis (TB) are challenged by the paucibacillary nature of the disease and the difficulties in obtaining specimens. We investigated the challenges in diagnosing TB in children in a low-incidence country.......Clinical investigations of childhood tuberculosis (TB) are challenged by the paucibacillary nature of the disease and the difficulties in obtaining specimens. We investigated the challenges in diagnosing TB in children in a low-incidence country....

  18. Use of bayesian operations for diagnosing accidents

    International Nuclear Information System (INIS)

    Kang, K.M.; Jae, M.; Suh, K.Y.

    2005-01-01

    In complex systems, it is necessary to model a logical representation of the overall system interaction with respect to the individual subsystems. Operators are allowed to follow EOPs (Emergency Operating Procedures) when reactor tripped because of accidents. But, it's very difficult to diagnose accidents and find out appropriate procedures to mitigate current accidents in a given short time. Even if they diagnose accidents, it also has possibility to misdiagnose. TMI accident is a good example of operators' errors. Methodology using Influence Diagrams has been developed and applied for representing the dependency behaviors and uncertain behaviors of complex systems. An example to diagnose the accidents such as SLOCA and SGTR with similar symptoms has been introduced. From the constructed model, operators could diagnose accidents at any states of accidents. This model can offer the information about accidents with given symptoms. This model might help operators to diagnose correctly and rapidly. It might be very useful to support operators to reduce human error. Also, from this study, it is applicable to diagnose other accidents with similar symptoms and to analyze causes of reactor trip. (authors)

  19. The Withdrawal of Health Care from Irregular Immigrants and Medical Conscientious Objection

    Directory of Open Access Journals (Sweden)

    Yolanda Garcìa Ruiz

    2016-12-01

    Full Text Available The economic crisis so strongly affecting some southern European countries has led to significant cuts in the system of universal public health care in Spain. Such measures particularly affect irregular immigrants and can also cause significant public health consequences. A form of civil resistance that deserves to be analyzed is the conscientious objection of Spanish doctors who have chosen to continue attending irregular immigrants in contravention of new the rules restricting their access to the public health system and their right to health. The aim of this paper is to analyze the new regulation which cut health care for irregular immigrants in Spain, the impact of this new regulation on the most vulnerable groups, and the response of doctors, who exercised their right to conscientious objection in relation to applying the new regulation. Finally to examine the announcement of change which came about as a consequence of international and domestic social pressure causing political risk to the Spanish National Government. La crisis económica, que ha afectado tan profundamente a algunos países del sur de Europa, ha dado lugar a significativos recortes en el sistema de atención sanitaria pública en España. Algunas de las medidas adoptadas han afectado específicamente a los inmigrantes irregulares y pueden tener, incluso, efectos en el ámbito de la salud pública. Una forma de desobediencia civil que merece ser analizada es la declaración de objeción de conciencia de determinados médicos y profesionales sanitarios españoles que han continuado atendiendo a los inmigrantes irregulares en contra de las nuevas  restricciones impuestas por el Gobierno que afectan al reconocimiento universal del derecho a la salud. El propósito de este artículo es el de analizar la nueva regulación que limita el acceso a la asistencia sanitaria de los inmigrantes irregulares en España, el impacto de esta nueva regulación en los grupos más vulnerables

  20. Simultaneous observations of ESF irregularities over Indian region using radar and GPS

    Directory of Open Access Journals (Sweden)

    S. Sripathi

    2008-10-01

    Full Text Available In this paper, we present simultaneous observations of temporal and spatial variability of total electron content (TEC and GPS amplitude scintillations on L1 frequency (1.575 GHz during the time of equatorial spread F (ESF while the MST radar (53 MHz located at Gadanki (13.5° N, 79.2° E, Dip latitude 6.3° N, a low latitude station, made simultaneous observations. In particular, the latitudinal and longitudinal extent of TEC and L-band scintillations was studied in the Indian region for different types of ESF structures observed using the MST radar during the low solar activity period of 2004 and 2005. Simultaneous radar and GPS observations during severe ESF events in the pre-midnight hour reveal that significant GPS L band scintillations, depletions in TEC, and the double derivative of the TEC index (DROTI, which is a measure of fluctuations in TEC, obtained at low latitudes coincide with the appearance of radar echoes at Gadanki. As expected, when the irregularities reach higher altitudes as seen in the radar map during pre-midnight periods, strong scintillations on an L-band signal are observed at higher latitudes. Conversely, when radar echoes are confined to only lower altitudes, weak scintillations are found and their latitudinal extent is small. During magnetically quiet periods, we have recorded plume type radar echoes during a post-midnight period that is devoid of L-band scintillations. Using spectral slopes and cross-correlation index of the VHF scintillation observations, we suggest that these irregularities could be "dead" or "fossil" bubbles which are just drifting in from west. This scenario is consistent with the observations where suppression of pre-reversal enhancement (PRE in the eastward electric field is indicated by ionosonde observations of the height of equatorial F layer and also occurrence of low spectral width in the radar observations relative to pre-midnight period. However, absence of L-band scintillations during

  1. Frequency and irregularity of heart rate in drivers suspected of driving under the influence of cannabis.

    Science.gov (United States)

    Khiabani, Hassan Z; Mørland, Jørg; Bramness, Jørgen G

    2008-12-01

    Delta 9-tetrahydrocannabinol (THC) is the major active component of cannabis. Cardiovascular effects of THC have previously been reported: tachycardia after intake, but also bradycardia at higher doses. The purpose of this study was, firstly, to investigate the frequency and irregularity of heart rate in a group of cannabis users in their natural surroundings. We also compared THC-positive drivers with a regular pulse with THC-positive drivers with an irregular pulse. The division of Forensic Toxicology and Drug Abuse (DFTDA) at the Norwegian Institute of Public Heath analyzes blood samples from all drivers suspected of driving under the influence of drugs. We studied pulse rate and regularity in 502 THC-positive drivers who tested negative for other substances. As a control group, we randomly selected 125 drug-negative cases from the database of the DFTDA; no alcohol, narcotics, or medicinal drugs of abuse were detected. The Delta9-THC-positive drivers had a higher mean pulse rate than the control group [82.8 beats/min (SD 16.3) versus 75.6 beats/min (SD 9.2)] and more cases with tachycardia were detected in the Delta9-THC-positive group (19.4% versus 1.6%). There was only one driver with an irregular heart beat in the control group, while there were nine among the Delta9-THC-positive drivers. The drivers with an irregular pulse were over-represented amongst those with the lowest blood Delta9-THC concentrations. This report represents a large study of subjects in a real-life situation and includes observations on pulse frequency, regularity, and blood Delta9-THC concentration. A substantial fraction of Delta9-THC-positive drivers had tachycardia, but there was no correlation between blood Delta9-THC concentration and pulse rate in the present study. We had no further diagnostic information on the cause of the pulse irregularities, but our results indicate that occasional users of cannabis tend to have irregular heart rates at low THC concentrations and at low

  2. Atmospheric pressure, density, temperature and wind variations between 50 and 200 km

    Science.gov (United States)

    Justus, C. G.; Woodrum, A.

    1972-01-01

    Data on atmospheric pressure, density, temperature and winds between 50 and 200 km were collected from sources including Meteorological Rocket Network data, ROBIN falling sphere data, grenade release and pitot tube data, meteor winds, chemical release winds, satellite data, and others. These data were analyzed by a daily difference method and results on the distribution statistics, magnitude, and spatial structure of the irregular atmospheric variations are presented. Time structures of the irregular variations were determined by the analysis of residuals from harmonic analysis of time series data. The observed height variations of irregular winds and densities are found to be in accord with a theoretical relation between these two quantities. The latitude variations (at 50 - 60 km height) show an increasing trend with latitude. A possible explanation of the unusually large irregular wind magnitudes of the White Sands MRN data is given in terms of mountain wave generation by the Sierra Nevada range about 1000 km west of White Sands. An analytical method is developed which, based on an analogy of the irregular motion field with axisymmetric turbulence, allows measured or model correlation or structure functions to be used to evaluate the effective frequency spectra of scalar and vector quantities of a spacecraft moving at any speed and at any trajectory elevation angle.

  3. Invaded depth of extrahepatic bile duct cancer diagnosed on angiographic CT during late contrast enhancement

    International Nuclear Information System (INIS)

    Kikuyama, Masataka; Sasada, Yuzo; Koide, Shigeki; Hirai, Ritsuko; Oota, Yuji

    2006-01-01

    Thirteen patients with extrahepatic bile duct cancer were evaluated for enhancement pattern and tumor feature during late contrast enhancement on angiographic CT (AG-CT), performed before surgery. Eleven patients with late contrast enhancement had advanced cancers with invasion over the subserosal layer. Eight of these patients whose cancer had an irregular outer layer had invasion over the serosal layer (≥panc 1 b, General Rules for Surgical and Pathological Studies on Cancer of the Biliary Tract, Japanese Society of Biliary Surgery). Seven of the 13 patients had intra-pancreatic bile duct cancer. Among them, five had an irregular outer layer of the intra-pancreatic bile duct cancer; one of three with a wall thickness under 5 mm on AG-CT had panc 1 b invasion, and the other two had panc 2 (General Rules for Surgical and Pathological Studies on Cancer of the Biliary Tract, Japanese Society of Biliary Surgery) invasion. Two with a wall thickness over 5 mm on AG-CT had panc 2 invasion. These results suggest that late contrast enhancement on AG-CT is effective for diagnosing the depth of tumor invasion of the bile duct. (author)

  4. Irregular Firing and High-Conductance States in Spinal Motoneurons during Scratching and Swimming

    DEFF Research Database (Denmark)

    Guzulaitis, Robertas; Hounsgaard, Jorn; Alaburda, Aidas

    2016-01-01

    UNLABELLED: Intense synaptic transmission during scratch network activity increases conductance and induces irregular firing in spinal motoneurons. It is not known whether this high-conductance state is a select feature for scratching or a property that goes with spinal motor network activity...... in general. Here we compare conductance and firing patterns in spinal motoneurons during network activity for scratching and swimming in an ex vivo carapace-spinal cord preparation from adult turtles (Trachemys scripta elegans). The pattern and relative engagement of motoneurons are distinctly different...... in scratching and swimming. Nevertheless, we found increased synaptic fluctuations in membrane potential, irregular firing, and increased conductance in spinal motoneurons during scratch and swim network activity. Our finding indicates that intense synaptic activation of motoneurons is a general feature...

  5. Provision of health services to irregular migrants with a special focus on children.

    Science.gov (United States)

    Søvig, Karl Harald

    2011-01-01

    All European countries are now facing a situation where a part of the population consists of migrants without a permit to stay or reside. These persons may have health problems, and the question then rises regarding health services to irregular migrants. Normally, welfare benefits are offered those with a relationship to the country concerned, as citizen, asylum seeker, tourist, etc. Irregular migrants are outside the society, and it could be suggested that they therefore should be denied health services. On the other hand, common European standards of humanity lay obligations on the States, for example, where situations are life-threatening. This contribution gives an overview of relevant legal instruments, both from the UN, Council of Europe and the European Union. Although there are many similarities, the instruments have their differences, and there may even be some tensions regarding the underlying values.

  6. Identifying irregularly shaped crime hot-spots using a multiobjective evolutionary algorithm

    Science.gov (United States)

    Wu, Xiaolan; Grubesic, Tony H.

    2010-12-01

    Spatial cluster detection techniques are widely used in criminology, geography, epidemiology, and other fields. In particular, spatial scan statistics are popular and efficient techniques for detecting areas of elevated crime or disease events. The majority of spatial scan approaches attempt to delineate geographic zones by evaluating the significance of clusters using likelihood ratio statistics tested with the Poisson distribution. While this can be effective, many scan statistics give preference to circular clusters, diminishing their ability to identify elongated and/or irregular shaped clusters. Although adjusting the shape of the scan window can mitigate some of these problems, both the significance of irregular clusters and their spatial structure must be accounted for in a meaningful way. This paper utilizes a multiobjective evolutionary algorithm to find clusters with maximum significance while quantitatively tracking their geographic structure. Crime data for the city of Cincinnati are utilized to demonstrate the advantages of the new approach and highlight its benefits versus more traditional scan statistics.

  7. The phase curve survey of the irregular saturnian satellites: A possible method of physical classification

    Science.gov (United States)

    Bauer, James M.; Grav, Tommy; Buratti, Bonnie J.; Hicks, Michael D.

    2006-09-01

    During its 2005 January opposition, the saturnian system could be viewed at an unusually low phase angle. We surveyed a subset of Saturn's irregular satellites to obtain their true opposition magnitudes, or nearly so, down to phase angle values of 0.01°. Combining our data taken at the Palomar 200-inch and Cerro Tololo Inter-American Observatory's 4-m Blanco telescope with those in the literature, we present the first phase curves for nearly half the irregular satellites originally reported by Gladman et al. [2001. Nature 412, 163-166], including Paaliaq (SXX), Siarnaq (SXXIX), Tarvos (SXXI), Ijiraq (SXXII), Albiorix (SXVI), and additionally Phoebe's narrowest angle brightness measured to date. We find centaur-like steepness in the phase curves or opposition surges in most cases with the notable exception of three, Albiorix and Tarvos, which are suspected to be of similar origin based on dynamical arguments, and Siarnaq.

  8. The influence of rail surface irregularities on contact forces and local stresses

    Science.gov (United States)

    Andersson, Robin; Torstensson, Peter T.; Kabo, Elena; Larsson, Fredrik

    2015-01-01

    The effect of initial rail surface irregularities on promoting further surface degradation is investigated. The study concerns rolling contact fatigue formation, in particular in the form of the so-called squats. The impact of surface irregularities in the form of dimples is quantified by peak magnitudes of dynamic contact stresses and contact forces. To this end simulations of two-dimensional (later extended to three-dimensional) vertical dynamic vehicle-track interaction are employed. The most influencing parameters are identified. It is shown that even very shallow dimples might have a large impact on local contact stresses. Peak magnitudes of contact forces and stresses due to the influence of rail dimples are shown to exceed those due to rail corrugation.

  9. Feasibility study of flexible phased array ultrasonic technology using irregular surface specimen

    International Nuclear Information System (INIS)

    Lee, Seung Pyo; Moon, Yong Sik; Jung, Nam Du

    2015-01-01

    Nuclear power plant contain many dissimilar metal welds that connect carbon steel components with stainless steel pipes using alloy 600 welding materials. Primary water stress corrosion cracks at dissimilar metal welds have been continuously reported around the world. In periodic integrity evaluations, dissimilar metal welds are examined using a generic ultrasonic testing procedure, KPD-UT-10. In this procedure, the gap between the probe and examination surface is limited to 1/32 inch (0.8 mm). It is not easy to test some dissimilar metal welds in Korean plants applying ordinary technology because of their tapered shapes and irregular surface conditions. This paper introduces a method for applying a flexible phased array technology to improve the reliability of ultrasonic testing results for various shapes and surface conditions. The artificial flaws in specimens with irregular surfaces were completely detected using the flexible phased array ultrasonic technology. Therefore, it can be said that the technology is applicable to field examination.

  10. Feasibility study of flexible phased array ultrasonic technology using irregular surface specimen

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Seung Pyo; Moon, Yong Sik; Jung, Nam Du [NDE Performance Demonstration Team, Korea Hydro and Nuclear Power, Central Research Institute, Daejeon (Korea, Republic of)

    2015-02-15

    Nuclear power plant contain many dissimilar metal welds that connect carbon steel components with stainless steel pipes using alloy 600 welding materials. Primary water stress corrosion cracks at dissimilar metal welds have been continuously reported around the world. In periodic integrity evaluations, dissimilar metal welds are examined using a generic ultrasonic testing procedure, KPD-UT-10. In this procedure, the gap between the probe and examination surface is limited to 1/32 inch (0.8 mm). It is not easy to test some dissimilar metal welds in Korean plants applying ordinary technology because of their tapered shapes and irregular surface conditions. This paper introduces a method for applying a flexible phased array technology to improve the reliability of ultrasonic testing results for various shapes and surface conditions. The artificial flaws in specimens with irregular surfaces were completely detected using the flexible phased array ultrasonic technology. Therefore, it can be said that the technology is applicable to field examination.

  11. Serbian migration policy concerning irregular migration and asylum in the context of the EU integration process

    Directory of Open Access Journals (Sweden)

    Marta Stojić-Mitrović

    2016-02-01

    Full Text Available In this paper I would like to present Serbian migration policy concerning irregular migration and asylum in the context of the attempts of the Serbian state to become a member of the European Union. I would describe the history of the asylum system prior and after the implementation of the independent asylum system in Serbia in 2008. My presentation of the Serbian migration policy would be channelled by the analysis of some particular political issues, such as the externalization of the EU borders’ control, as well as some relevant elements of the European integration process, like visa liberalization. The second, more culturally specific dimension of the issue would be accessed through the demonstration of both legislative and public conceptualizations of the irregular migrants, asylum seekers and refugees in Serbia.

  12. CORPORATE GOVERNANCE AND ACCOUNTING IRREGULARITIES: Evidence from the Two-tiered Board Structure in Indonesia

    Directory of Open Access Journals (Sweden)

    Jaswadi JASWADI

    2012-09-01

    Full Text Available This study aims to investigate the extent to which the Indonesian corporate governance mechanism acts as an effective tool for protecting financial statements users against accounting irregularities. Considering that accounting irregularities might occur in between error and the fraud act, this study reviews the literature on minimizing the seriousness of these reporting incidences. The level of seriousness in misstatements is more severe when: (1 there is absence of financial expert(s on supervisory boards and audit committees, (2 companies have short tenured-CEOs and poor internal control systems, and (3 auditors are solely appointed by firms’ BOCs without agreement of block holders (known as referral. In addition, an examination of simultaneous effects of each corporate governance dimension reveals a general weakness of the BOCs and their audit committees. However, the BOC and audit committee could be an effective tool in mitigating reporting incidences, especially when they show high-quality collaboration.

  13. Stability Analysis Method for Rock Slope with an Irregular Shear Plane Based on Interface Model

    Directory of Open Access Journals (Sweden)

    Changqing Qi

    2018-01-01

    Full Text Available Landslide developed in rock mass usually has irregular shear plane. An approach for calculating distributed factor of safety of the irregular shear plane was put forward in this paper. The presented method can obtain not only the detailed stability status at any grid node of a complex shear plane but also the global safety of the slope. Thus, it is helpful to thoroughly understand the mechanism of slope failure. Comparing with the result obtained through the limit equilibrium method, the presented method was proved to be more accurate and suitable for stability analysis of rock slope with a thin shear plane. The stability of a potentially unstable rock slope was analyzed based on the presented method at the end of this paper. The detailed local stability, global stability, and the potential failure mechanism were provided.

  14. Mei symmetry and conservation laws of discrete nonholonomic dynamical systems with regular and irregular lattices

    International Nuclear Information System (INIS)

    Zhao Gang-Ling; Chen Li-Qun; Fu Jing-Li; Hong Fang-Yu

    2013-01-01

    In this paper, Noether symmetry and Mei symmetry of discrete nonholonomic dynamical systems with regular and the irregular lattices are investigated. Firstly, the equations of motion of discrete nonholonomic systems are introduced for regular and irregular lattices. Secondly, for cases of the two lattices, based on the invariance of the Hamiltomian functional under the infinitesimal transformation of time and generalized coordinates, we present the quasi-extremal equation, the discrete analogues of Noether identity, Noether theorems, and the Noether conservation laws of the systems. Thirdly, in cases of the two lattices, we study the Mei symmetry in which we give the discrete analogues of the criterion, the theorem, and the conservative laws of Mei symmetry for the systems. Finally, an example is discussed for the application of the results

  15. Method of adiabatic modes in studying problems of smoothly irregular open waveguide structures

    International Nuclear Information System (INIS)

    Sevastianov, L. A.; Egorov, A. A.; Sevastyanov, A. L.

    2013-01-01

    Basic steps in developing an original method of adiabatic modes that makes it possible to solve the direct and inverse problems of simulating and designing three-dimensional multilayered smoothly irregular open waveguide structures are described. A new element in the method is that an approximate solution of Maxwell’s equations is made to obey “inclined” boundary conditions at the interfaces between themedia being considered. These boundary conditions take into account the obliqueness of planes tangent to nonplanar boundaries between the media and lead to new equations for coupled vector quasiwaveguide hybrid adiabatic modes. Solutions of these equations describe the phenomenon of “entanglement” of two linear polarizations of an irregular multilayered waveguide, the appearance of a new mode in an entangled state, and the effect of rotation of the polarization plane of quasiwaveguide modes. The efficiency of the method is demonstrated by considering the example of numerically simulating a thin-film generalized waveguide Lüneburg lens.

  16. An Efficient Heuristic Approach for Irregular Cutting Stock Problem in Ship Building Industry

    Directory of Open Access Journals (Sweden)

    Yan-xin Xu

    2016-01-01

    Full Text Available This paper presents an efficient approach for solving a real two-dimensional irregular cutting stock problem in ship building industry. Cutting stock problem is a common cutting and packing problem that arises in a variety of industrial applications. A modification of selection heuristic Exact Fit is applied in our research. In the case referring to irregular shapes, a placement heuristics is more important to construct a complete solution. A placement heuristic relating to bottom-left-fill is presented. We evaluate the proposed approach using generated instance only with convex shapes in literatures and some instances with nonconvex shapes based on real problem from ship building industry. The results demonstrate that the effectiveness and efficiency of the proposed approach are significantly better than some conventional heuristics.

  17. An experimental study of irregular wave forces on multiple quasi-ellipse caissons

    Science.gov (United States)

    Ren, Xiaozhong; Zhang, Peng; Ma, Yuxiang; Meng, Yufan

    2014-09-01

    An experimental investigation of irregular wave forces on quasi-ellipse caisson structures is presented. Irregular waves were generated based on the Jonswap spectrum with two significant wave heights, and the spectrum peak periods range from 1.19 s to 1.81 s. Incident wave directions relative to the centre line of the multiple caissons are from 0° to 22.5°. The spacing between caissons ranges from 2 to 3 times that of the width of the caisson. The effects of these parameters on the wave forces of both the perforated and non-perforated caissons were compared and analyzed. It was found that the perforated caisson can reduce wave forces, especially in the transverse direction. Furthermore, the relative interval and incident wave direction have significant effects on the wave forces in the case of multiple caissons.

  18. Time-Scale and Time-Frequency Analyses of Irregularly Sampled Astronomical Time Series

    Directory of Open Access Journals (Sweden)

    S. Roques

    2005-09-01

    Full Text Available We evaluate the quality of spectral restoration in the case of irregular sampled signals in astronomy. We study in details a time-scale method leading to a global wavelet spectrum comparable to the Fourier period, and a time-frequency matching pursuit allowing us to identify the frequencies and to control the error propagation. In both cases, the signals are first resampled with a linear interpolation. Both results are compared with those obtained using Lomb's periodogram and using the weighted waveletZ-transform developed in astronomy for unevenly sampled variable stars observations. These approaches are applied to simulations and to light variations of four variable stars. This leads to the conclusion that the matching pursuit is more efficient for recovering the spectral contents of a pulsating star, even with a preliminary resampling. In particular, the results are almost independent of the quality of the initial irregular sampling.

  19. A research about characteristics of longitudinal variations of ES layers irregularities based on CHAMP occultation measurements

    Science.gov (United States)

    Liao, Sunmin

    2018-04-01

    Based on the data of CHAMP occultation measurements, this paper makes a preliminary analysis of the longitudinal variations of ES irregular structure by using Fourier decomposition and reconstruction technique. It is found that the longitudinal variations of the ES irregular structure show the features of multiple wave-numbers, which is dominated by the wave number 1 to the wave number 5 components, and decrease from the amplitudes of the wave number 6 components. The features of wave number structures are very different in different DIP latitude and different seasons. The number of crests in summer and autumn is mostly 3 or 4 crest structures, while the number of crests in spring achieves 5 at DIP 15°N with small fluctuates, the crests number of winter is the least. In the multiple wave-numbers structure, the wave number 4 component shows a significant dependence on the season, mainly in the summer and autumn, particularly obvious from July to October.

  20. Irregular Polyomino-Shaped Subarrays for Space-Based Active Arrays

    Directory of Open Access Journals (Sweden)

    R. J. Mailloux

    2009-01-01

    Full Text Available This paper presents new results showing the application of polyomino-based subarrays to limited field of view and wideband, wide-angle scanning. This technology can reduce the number of phase controls in arrays used for limited sector coverage or the number of time delay devices for wideband radar or communications, and so can reduce the cost of space-based active arrays. We concentrate on the wideband application. Results are presented by comparing the gain and peak sidelobe results of irregular polyomino subarray-based arrays with those of rectangular subarrays. It is shown that using irregular polyomino subarrays can result in a major decrease in sidelobes while presenting, in most cases, only a few tenths of a dB gain reduction compared to rectangular subarrays.

  1. A Hybrid Model Based on Wavelet Decomposition-Reconstruction in Track Irregularity State Forecasting

    Directory of Open Access Journals (Sweden)

    Chaolong Jia

    2015-01-01

    Full Text Available Wavelet is able to adapt to the requirements of time-frequency signal analysis automatically and can focus on any details of the signal and then decompose the function into the representation of a series of simple basis functions. It is of theoretical and practical significance. Therefore, this paper does subdivision on track irregularity time series based on the idea of wavelet decomposition-reconstruction and tries to find the best fitting forecast model of detail signal and approximate signal obtained through track irregularity time series wavelet decomposition, respectively. On this ideology, piecewise gray-ARMA recursive based on wavelet decomposition and reconstruction (PG-ARMARWDR and piecewise ANN-ARMA recursive based on wavelet decomposition and reconstruction (PANN-ARMARWDR models are proposed. Comparison and analysis of two models have shown that both these models can achieve higher accuracy.

  2. Irregular or absent periods--what can an ultrasound scan tell you?

    Science.gov (United States)

    Khalid, Asma

    2004-02-01

    Transvaginal ultrasonography has increased our appreciation of the physiological changes in the ovary and endometrium that occur during the normal menstrual cycle. It has become a primary investigative tool in women with irregular or absent periods. Its usefulness in cases of primary amenorrhoea to assess anatomy is also undisputed although it may have limitations in terms of its specificity. However, the interpretation of ultrasound images in women with irregular menses or secondary amenorrhoea is not entirely straightforward. This is particularly true in the diagnosis of polycystic ovary syndrome, a condition of uncertain aetiology, which may present with oligoamenorrhoea. This chapter aims to discuss the benefits and limitations of ultrasound while taking into account the broad overlap between normal and abnormal physiology, some of which has still to be elucidated.

  3. Systematic study of intermediate-scale structures of equatorial plasma irregularities in the ionosphere based on CHAMP observations

    Directory of Open Access Journals (Sweden)

    Hermann eLühr

    2014-03-01

    Full Text Available Equatorial spread-F ionospheric plasma irregularities on the night-side, commonly called equatorial plasma bubbles (EPB, include electron density variations over a wide range of spatial scales. Here we focus on intermediate-scale structures ranging from 100 m to 10 km, which play an important role in the evolution of EPBs. High-resolution CHAMP magnetic field measurements sampled along north-south track at 50 Hz are interpreted in terms of diamagnetic effect for illustrating the details of electron density variations. We provide the first comprehensive study on intermediate-scale density structures associated with EPBs, covering a whole solar cycle from 2000 to 2010. The large number of detected events, almost 9000, allows us to draw a detailed picture of the plasma fine structure. The occurrence of intermediate-scale events is strongly favoured by high solar flux. During times of F10.7 < 100 sfu practically no events were observed. The longitudinal distribution of our events with respect to season or local time agrees well with that of the EPBs, qualifying the fine structure as a common feature, but the occurrence rates are smaller by a factor of 4 during the period 2000-2005. Largest amplitude electron density variations appear at the poleward boundaries of plasma bubbles. Above the dip-equator recorded amplitudes are small and fall commonly below our resolution. Events can generally be found at local times between 19 and 24 LT, with a peak lasting from 20 to 22 LT. The signal spectrum can be approximated by a power law. Over the frequency range 1 – 25 Hz we observe spectral indices between -1.4 and -2.6 with peak occurrence rates around -1.9. There is a weak dependence observed of the spectral index on local time. Towards later hours the spectrum becomes shallower. Similarly for the latitude dependence, there is a preference of shallower spectra for latitudes poleward of the ionisation anomaly crest. Our data suggest that the generation of

  4. Analysis of the Dynamic Response in the Railway Vehicles to the Track Vertical Irregularities. Part I: The Theoretical Model and the Vehicle Response Functions

    Directory of Open Access Journals (Sweden)

    M. Dumitriu

    2015-11-01

    Full Text Available The paper herein focuses on the dynamic response of a two-bogie vehicle to the excitations derived from the track vertical irregularities. The symmetrical and antisymmetrical modes due from the bounce and pitch motions of the axles’ planes in the two bogies are being considered. The analysis of the dynamic response in the vehicle relies on the response functions in three reference points of the carbody, composed by means of these response functions to the symmetrical and antisymmetrical excitation modes. Similarly, the dynamic response of the vehicle to the track stochastic irregularities is examined and expressed as a power spectral density of the carbody vertical acceleration and the root mean square of the acceleration and the index of the partial comfort to the vertical vibrations is calculated. The paper is structured into two parts. The Part I includes all the theoretical elements required for the analysis of the dynamic response in the vehicle, while Part II introduces the results of the numerical analysis.

  5. Development of Computer Program for Analysis of Irregular Non Homogenous Radiation Shielding

    International Nuclear Information System (INIS)

    Bang Rozali; Nina Kusumah; Hendro Tjahjono; Darlis

    2003-01-01

    A computer program for radiation shielding analysis has been developed to obtain radiation attenuation calculation in non-homogenous radiation shielding and irregular geometry. By determining radiation source strength, geometrical shape of radiation source, location, dimension and geometrical shape of radiation shielding, radiation level of a point at certain position from radiation source can be calculated. By using a computer program, calculation result of radiation distribution analysis can be obtained for some analytical points simultaneously. (author)

  6. Direct solution of the biharmonic equation on rectangular regions and the Poisson equation on irregular regions

    International Nuclear Information System (INIS)

    Buzbee, B.L.; Dorr, F.W.

    1974-01-01

    The discrete biharmonic equation on a rectangular region and the discrete Poisson equation on an irregular region can be treated as modifications to matrix problems with very special structure. It is shown how to use the direct method of matrix decomposition to formulate an effective numerical algorithm for these problems. For typical applications the operation count is O(N 3 ) for an N x N grid. Numerical comparisons with other techniques are included. (U.S.)

  7. Tremor irregularity, torque steadiness and rate of force development in Parkinson's disease

    DEFF Research Database (Denmark)

    Rose, Martin Høyer; Løkkegaard, Annemette; Sonne-Holm, Stig

    2013-01-01

    with idiopathic PD and 15 neurologically healthy matched controls performed isometric maximal contractions (extension/flexion) as well as steady submaximal and powerful isometric knee extensions. The patients with PD showed decreased isometric tremor irregularity. Torque steadiness was reduced in PD...... that both knee isometric tremor Approximate Entropy and torque steadiness clearly differentiate between patients with PD and healthy controls. Furthermore, severely compromised RFD was found in patients with PD and was associated with decreased agonist muscle activation....

  8. Penalized likelihood and multi-objective spatial scans for the detection and inference of irregular clusters

    Directory of Open Access Journals (Sweden)

    Fonseca Carlos M

    2010-10-01

    Full Text Available Abstract Background Irregularly shaped spatial clusters are difficult to delineate. A cluster found by an algorithm often spreads through large portions of the map, impacting its geographical meaning. Penalized likelihood methods for Kulldorff's spatial scan statistics have been used to control the excessive freedom of the shape of clusters. Penalty functions based on cluster geometry and non-connectivity have been proposed recently. Another approach involves the use of a multi-objective algorithm to maximize two objectives: the spatial scan statistics and the geometric penalty function. Results & Discussion We present a novel scan statistic algorithm employing a function based on the graph topology to penalize the presence of under-populated disconnection nodes in candidate clusters, the disconnection nodes cohesion function. A disconnection node is defined as a region within a cluster, such that its removal disconnects the cluster. By applying this function, the most geographically meaningful clusters are sifted through the immense set of possible irregularly shaped candidate cluster solutions. To evaluate the statistical significance of solutions for multi-objective scans, a statistical approach based on the concept of attainment function is used. In this paper we compared different penalized likelihoods employing the geometric and non-connectivity regularity functions and the novel disconnection nodes cohesion function. We also build multi-objective scans using those three functions and compare them with the previous penalized likelihood scans. An application is presented using comprehensive state-wide data for Chagas' disease in puerperal women in Minas Gerais state, Brazil. Conclusions We show that, compared to the other single-objective algorithms, multi-objective scans present better performance, regarding power, sensitivity and positive predicted value. The multi-objective non-connectivity scan is faster and better suited for the

  9. Measurements of linear attenuation coefficients of irregular shaped samples by two media method

    International Nuclear Information System (INIS)

    Singh, Sukhpal; Kumar, Ashok; Thind, Kulwant Singh; Mudahar, Gurmel S.

    2008-01-01

    The linear attenuation coefficient values of regular and irregular shaped flyash materials have been measured without knowing the thickness of a sample using a new technique namely 'two media method'. These values have also been measured with a standard gamma ray transmission method and obtained theoretically with winXCOM computer code. From the comparison it is reported that the two media method has given accurate results of attenuation coefficients of flyash materials

  10. Exploring Hardware Support For Scaling Irregular Applications on Multi-node Multi-core Architectures

    Energy Technology Data Exchange (ETDEWEB)

    Secchi, Simone; Ceriani, Marco; Tumeo, Antonino; Villa, Oreste; Palermo, Gianluca; Raffo, Luigi

    2013-06-05

    With the recent emergence of large-scale knowledge dis- covery, data mining and social network analysis, irregular applications have gained renewed interest. Classic cache-based high-performance architectures do not provide optimal performances with such kind of workloads, mainly due to the very low spatial and temporal locality of the irregular control and memory access patterns. In this paper, we present a multi-node, multi-core, fine-grained multi-threaded shared-memory system architecture specifically designed for the execution of large-scale irregular applications, and built on top of three pillars, that we believe are fundamental to support these workloads. First, we offer transparent hardware support for Partitioned Global Address Space (PGAS) to provide a large globally-shared address space with no software library overhead. Second, we employ multi-threaded multi-core processing nodes to achieve the necessary latency tolerance required by accessing global memory, which potentially resides in a remote node. Finally, we devise hardware support for inter-thread synchronization on the whole global address space. We first model the performances by using an analytical model that takes into account the main architecture and application characteristics. We describe the hardware design of the proposed cus- tom architectural building blocks that provide support for the above- mentioned three pillars. Finally, we present a limited-scale evaluation of the system on a multi-board FPGA prototype with typical irregular kernels and benchmarks. The experimental evaluation demonstrates the architecture performance scalability for different configurations of the whole system.

  11. From inverse problems in mathematical physiology to quantitative differential diagnoses.

    Directory of Open Access Journals (Sweden)

    Sven Zenker

    2007-11-01

    Full Text Available The improved capacity to acquire quantitative data in a clinical setting has generally failed to improve outcomes in acutely ill patients, suggesting a need for advances in computer-supported data interpretation and decision making. In particular, the application of mathematical models of experimentally elucidated physiological mechanisms could augment the interpretation of quantitative, patient-specific information and help to better target therapy. Yet, such models are typically complex and nonlinear, a reality that often precludes the identification of unique parameters and states of the model that best represent available data. Hypothesizing that this non-uniqueness can convey useful information, we implemented a simplified simulation of a common differential diagnostic process (hypotension in an acute care setting, using a combination of a mathematical model of the cardiovascular system, a stochastic measurement model, and Bayesian inference techniques to quantify parameter and state uncertainty. The output of this procedure is a probability density function on the space of model parameters and initial conditions for a particular patient, based on prior population information together with patient-specific clinical observations. We show that multimodal posterior probability density functions arise naturally, even when unimodal and uninformative priors are used. The peaks of these densities correspond to clinically relevant differential diagnoses and can, in the simplified simulation setting, be constrained to a single diagnosis by assimilating additional observations from dynamical interventions (e.g., fluid challenge. We conclude that the ill-posedness of the inverse problem in quantitative physiology is not merely a technical obstacle, but rather reflects clinical reality and, when addressed adequately in the solution process, provides a novel link between mathematically described physiological knowledge and the clinical concept of

  12. From Inverse Problems in Mathematical Physiology to Quantitative Differential Diagnoses

    Science.gov (United States)

    Zenker, Sven; Rubin, Jonathan; Clermont, Gilles

    2007-01-01

    The improved capacity to acquire quantitative data in a clinical setting has generally failed to improve outcomes in acutely ill patients, suggesting a need for advances in computer-supported data interpretation and decision making. In particular, the application of mathematical models of experimentally elucidated physiological mechanisms could augment the interpretation of quantitative, patient-specific information and help to better target therapy. Yet, such models are typically complex and nonlinear, a reality that often precludes the identification of unique parameters and states of the model that best represent available data. Hypothesizing that this non-uniqueness can convey useful information, we implemented a simplified simulation of a common differential diagnostic process (hypotension in an acute care setting), using a combination of a mathematical model of the cardiovascular system, a stochastic measurement model, and Bayesian inference techniques to quantify parameter and state uncertainty. The output of this procedure is a probability density function on the space of model parameters and initial conditions for a particular patient, based on prior population information together with patient-specific clinical observations. We show that multimodal posterior probability density functions arise naturally, even when unimodal and uninformative priors are used. The peaks of these densities correspond to clinically relevant differential diagnoses and can, in the simplified simulation setting, be constrained to a single diagnosis by assimilating additional observations from dynamical interventions (e.g., fluid challenge). We conclude that the ill-posedness of the inverse problem in quantitative physiology is not merely a technical obstacle, but rather reflects clinical reality and, when addressed adequately in the solution process, provides a novel link between mathematically described physiological knowledge and the clinical concept of differential diagnoses

  13. A 27-year-old woman diagnosed as polycystic ovary syndrome associated with Graves' disease.

    Science.gov (United States)

    Jung, Jung Hwa; Hahm, Jong Ryeal; Jung, Tae Sik; Kim, Hee Jin; Kim, Ho Soo; Kim, Sungsu; Kim, Soo Kyoung; Lee, Sang Min; Kim, Deok Ryong; Choi, Won Jun; Seo, Yeong Mi; Chung, Soon Il

    2011-01-01

    Polycystic ovary syndrome (PCOS) and Graves' disease are the common causes of menstrual irregularity leading to infertility in women of child-bearing age. A 21-year-old female patient visited us with complaints of oligomenorrhea and hand tremor. She was diagnosed as having PCOS and hyperthyroid Graves' disease, simultaneously. She had low body weight (BMI: 16.4 kg/m(2)), mild hirsutism, and thyrotoxicosis. The patient was treated with anti-thyroid drug and beta-blocker for about two years, and then recovered to normal thyroid function. Although some studies have suggested a connection between PCOS and autoimmune thyroiditis, no study indicated that PCOS is associated with Graves' disease until now. Here, we describe the first case report of a lean woman with normal insulin sensitivity presenting PCOS and Graves' disease simultaneously.

  14. Zonal drifts of ionospheric irregularities at temperate latitude in the Indian region

    Directory of Open Access Journals (Sweden)

    S. Kumar

    1995-07-01

    Full Text Available The systematic time differences observed in the onset of postsunset VHF scintillations recorded simultaneously at Ujjain (Geogr. lat. 23.2°N, Geogr. long. 75.6°E and Bhopal (Geogr. lat. 23.2°N, Geogr. long. 77.6°E, situated at the peak of the anomaly crest in the Indian region, have been analysed to determine the zonal drifts of scintillation-producing irregularities. The method is based on the assumption that the horizontal movement of irregularities does not change while crossing the F-region cross-over points of these stations. The calculated velocities of irregularities indicate an eastward drift decreasing from about 180 m s–1 to 55 m s–1 during the course of night. In the premidnight period, the drifts are reduced under the magnetically disturbed conditions. The average east-west extension of irregularites is found to be in the range of 200–500 km.

  15. MPPT-Based Control Algorithm for PV System Using iteration-PSO under Irregular shadow Conditions

    Directory of Open Access Journals (Sweden)

    M. Abdulkadir

    2017-02-01

    Full Text Available The conventional maximum power point tracking (MPPT techniques can hardly track the global maximum power point (GMPP because the power-voltage characteristics of photovoltaic (PV exhibit multiple local peaks in irregular shadow, and therefore easily fall into the local maximum power point. These conditions make it very challenging, and to tackle this deficiency, an efficient Iteration Particle Swarm Optimization (IPSO has been developed to improve the quality of solution and convergence speed of the traditional PSO, so that it can effectively track the GMPP under irregular shadow conditions. This proposed technique has such advantages as simple structure, fast response and strong robustness, and convenient implementation. It is applied to MPPT control of PV system in irregular shadow to solve the problem of multi-peak optimization in partial shadow. In order to verify the rationality of the proposed algorithm, however, recently the dynamic MPPT performance under varying irradiance conditions has been given utmost attention to the PV society. As the European standard EN 50530 which defines the recommended varying irradiance profiles, was released lately, the corresponding researchers have been required to improve the dynamic MPPT performance. This paper tried to evaluate the dynamic MPPT performance using EN 50530 standard. The simulation results show that iterative-PSO method can fast track the global MPP, increase tracking speed and higher dynamic MPPT efficiency under EN 50530 than the conventional PSO.

  16. Surface Irregularity Factor as a Parameter to Evaluate the Fatigue Damage State of CFRP

    Science.gov (United States)

    Zuluaga-Ramírez, Pablo; Frövel, Malte; Belenguer, Tomás; Salazar, Félix

    2015-01-01

    This work presents an optical non-contact technique to evaluate the fatigue damage state of CFRP structures measuring the irregularity factor of the surface. This factor includes information about surface topology and can be measured easily on field, by techniques such as optical perfilometers. The surface irregularity factor has been correlated with stiffness degradation, which is a well-accepted parameter for the evaluation of the fatigue damage state of composite materials. Constant amplitude fatigue loads (CAL) and realistic variable amplitude loads (VAL), representative of real in- flight conditions, have been applied to “dog bone” shaped tensile specimens. It has been shown that the measurement of the surface irregularity parameters can be applied to evaluate the damage state of a structure, and that it is independent of the type of fatigue load that has caused the damage. As a result, this measurement technique is applicable for a wide range of inspections of composite material structures, from pressurized tanks with constant amplitude loads, to variable amplitude loaded aeronautical structures such as wings and empennages, up to automotive and other industrial applications. PMID:28793655

  17. Wireless sensing without sensors—an experimental study of motion/intrusion detection using RF irregularity

    International Nuclear Information System (INIS)

    Lee, Pius W Q; Tan, Hwee-Pink; Seah, Winston K G; Yao, Zexi

    2010-01-01

    Motion and intrusion detection are often cited as wireless sensor network (WSN) applications with typical configurations comprising clusters of wireless nodes equipped with motion sensors to detect human motion. Currently, WSN performance is subjected to several constraints, namely radio irregularity and finite on-board computation/energy resources. Radio irregularity in radio frequency (RF) propagation rises to a higher level in the presence of human activity due to the absorption effect of the human body. In this paper, we investigate the feasibility of monitoring RF transmission for the purpose of intrusion detection through experimentation. With empirical data obtained from the Crossbow TelosB platform in several different environments, the impact of human activity on the signal strength of RF signals in a WSN is evaluated. We then propose a novel approach to intrusion detection by turning a constraint in WSN, namely radio irregularity, into an advantage for the purpose of intrusion detection, using signal fluctuations to detect the presence of human activity within the WSN. Unlike RF fingerprinting, the 'intruders' here neither transmit nor receive any RF signals. By enabling existing wireless infrastructures to serve as intrusion detectors instead of deploying numerous costly sensors, this approach shows great promise for providing novel solutions

  18. Validation of AEGIS/SCOPE2 system through actual core follow calculations with irregular operational conditions

    International Nuclear Information System (INIS)

    Tabuchi, M.; Tatsumi, M.; Ohoka, Y.; Nagano, H.; Ishizaki, K.

    2017-01-01

    This paper describes overview of AEGIS/SCOPE2 system, an advanced in-core fuel management system for pressurized water reactors, and its validation results of actual core follow calculations including irregular operational conditions. AEGIS and SCOPE2 codes adopt more detailed and accurate calculation models compared to the current core design codes while computational cost is minimized with various techniques on numerical and computational algorithms. Verification and validation of AEGIS/SCOPE2 has been intensively performed to confirm validity of the system. As a part of the validation, core follow calculations have been carried out mainly for typical operational conditions. After the Fukushima Daiichi nuclear power plant accident, however, all the nuclear reactors in Japan suffered from long suspension and irregular operational conditions. In such situations, measured data in the restart and operation of the reactors should be good examinations for validation of the codes. Therefore, core follow calculations were carried out with AEGIS/SCOPE2 for various cases including zero power reactor physics tests with irregular operational conditions. Comparisons between measured data and predictions by AEGIS/SCOPE2 revealed the validity and robustness of the system. (author)

  19. Transformation-cost time-series method for analyzing irregularly sampled data.

    Science.gov (United States)

    Ozken, Ibrahim; Eroglu, Deniz; Stemler, Thomas; Marwan, Norbert; Bagci, G Baris; Kurths, Jürgen

    2015-06-01

    Irregular sampling of data sets is one of the challenges often encountered in time-series analysis, since traditional methods cannot be applied and the frequently used interpolation approach can corrupt the data and bias the subsequence analysis. Here we present the TrAnsformation-Cost Time-Series (TACTS) method, which allows us to analyze irregularly sampled data sets without degenerating the quality of the data set. Instead of using interpolation we consider time-series segments and determine how close they are to each other by determining the cost needed to transform one segment into the following one. Using a limited set of operations-with associated costs-to transform the time series segments, we determine a new time series, that is our transformation-cost time series. This cost time series is regularly sampled and can be analyzed using standard methods. While our main interest is the analysis of paleoclimate data, we develop our method using numerical examples like the logistic map and the Rössler oscillator. The numerical data allows us to test the stability of our method against noise and for different irregular samplings. In addition we provide guidance on how to choose the associated costs based on the time series at hand. The usefulness of the TACTS method is demonstrated using speleothem data from the Secret Cave in Borneo that is a good proxy for paleoclimatic variability in the monsoon activity around the maritime continent.

  20. Electromagnetic waves in irregular multilayered spheroidal structures of finite conductivity: full wave solutions

    International Nuclear Information System (INIS)

    Bahar, E.

    1976-01-01

    The propagation of electromagnetic waves excited by electric dipoles oriented along the axis of multilayered spheroidal structures of finite conductivity is investigated. The electromagnetic parameters and the thickness of the layers of the structure are assumed to be functions of the latitude. In the analysis, electric and magnetic field transforms that constitute a discrete and a continuous spectrum of spherical waves are used to provide a suitable basis for the expansion of the electromagnetic fields at any point in the irregular spheroidal structure. For spheroidal structures with good conducting cores, the terms in the solutions associated with the continuous part of the wave spectrum vanish. In general, however, when the skin depth for the core is large compared to its dimensions or when the sources are located in the core of the structure and propagation in the core is of special interest, the contribution from the continuous part of the wave spectrum cannot be neglected. At each interface between the layers of the irregular spheroidal structure, exact boundary conditions are imposed. Since the terms of the field expansions in the irregular structure do not individually satisfy the boundary conditions, Maxwell's equations are reduced to sets of coupled ordinary first-order differential equations for the wave amplitudes. The solutions are shown to satisfy the reciprocity relationships in electromagnetic theory. The analysis may be applied to problems of radio wave propagation in a nonuniform model of the earth-ionosphere waveguide, particularly when focusing effects at the antipodes are important