WorldWideScience

Sample records for bows

  1. Bowed Strings

    Science.gov (United States)

    Rossing, Thomas D.; Hanson, Roger J.

    In the next eight chapters, we consider some aspects of the science of bowed string instruments, old and new. In this chapter, we present a brief discussion of bowed strings, a subject that will be developed much more thoroughly in Chap. 16. Chapters 13-15 discuss the violin, the cello, and the double bass. Chapter 17 discusses viols and other historic string instruments, and Chap. 18 discusses the Hutchins-Schelleng violin octet.

  2. Bow Crushing Forces

    DEFF Research Database (Denmark)

    Pedersen, Preben Terndrup

    1996-01-01

    The purpose of these notes is to present a basis for the estimation of the internal collision forces between conventinal merchant vessels and large volume offshore structures in the form of gravity-supported offshore installations and bridges crossing international shipping routes.The main emphasis...... is on the presentation of impact loads on fixed offshore structures due to bow collisions. The crushing forces are determined as functions of vessels size, vessels speed, bow profile, collision angles and eccentric impacts....

  3. Bow and catapult internal dynamics

    CERN Document Server

    Denny, M

    2003-01-01

    A simple model of bow and arrow dynamics is presented, which makes clear the physical principles, and reproduces the features obtained via more detailed, but less accessible calculations. We apply this instructive model to determine the efficiency of bows and of torsion-spring catapults.

  4. Articulated coordination of the right arm underlies control of bow parameters and quick bow reversals in skilled cello bowing

    OpenAIRE

    Julius eVerrel; Marjorie Hines Woollacott; Ulman eLindenberger

    2014-01-01

    Stringed instrument bowing is a complex coordinative motor skill acquired though years of intense practice. We apply a novel “freezing” analysis to investigate how movement at different joints contributes to bow transport (movement amplitude), stabilization of bow parameters (angle, velocity) during bow movements, and quick reversals of bow direction (acceleration amplitude). Participants were ten advanced or professional cellists (19–32 years, at least 10 years of practice) and ten age-match...

  5. Articulated coordination of the right arm underlies control of bow parameters and quick bow reversals in skilled cello bowing.

    Science.gov (United States)

    Verrel, Julius; Woollacott, Marjorie; Lindenberger, Ulman

    2014-01-01

    Stringed instrument bowing is a complex coordinative motor skill acquired though years of intense practice. We apply a novel "freezing" analysis to investigate how movement at different joints contributes to bow transport (movement amplitude), stabilization of bow parameters (angle, velocity) during bow movements, and quick reversals of bow direction (acceleration amplitude). Participants were ten advanced or professional cellists (19-32 years, at least 10 years of practice) and ten age-matched novice players. Arm and bow movements were recorded using 3D motion capture. To assess how performance depends on articulated use of the right arm, actual data were compared to surrogate data, generated by artificially removing movement at ("freezing") individual joints in measured arm movements. This analysis showed that both elbow and shoulder significantly contribute to bow transport in experts, while only the shoulder contributed to bow transport in novices. Moreover, experts showed more strongly increased variability of bow parameters and reduced acceleration amplitudes at bow reversals for surrogate compared to actual movement data. This indicates that movement across joints was organized to reduce bow variability and achieve quick bow reversals. Corresponding effects were less pronounced or absent in the novices, in particular for the wrist and elbow. Our results demonstrate the importance of articulated use of the right arm and clarify the contribution of different joints in experts' bowing performance. Moreover, they support theories of motor control and learning that propose exploitation of biomechanical degrees of freedom, in particular of distal joints, as a critical component in skilled motor performance.

  6. The player and the bowed string: coordination of bowing parameters in violin and viola performance.

    Science.gov (United States)

    Schoonderwaldt, E

    2009-11-01

    An experiment was conducted with four violin and viola players, measuring their bowing performance using an optical motion capture system and sensors on the bow. The measurements allowed for a detailed analysis of the use and coordination of the main bowing parameters bow velocity, bow force, and bow-bridge distance. An analysis of bowing strategies in detache playing of notes of three durations (0.2, 2, and 4 s) at three dynamic levels (pp, mf, and f) on all four strings is presented, focusing on the "steady" part of the notes. The results revealed clear trends in the coordinated variations of the bowing parameters depending on the constraints of the task, reflecting a common behavior as well as individual strategies. Furthermore, there were clear indications that the players adapted the bowing parameters to the physical properties of the string and the instrument, respecting the limits of the playable control parameter space.

  7. Articulated coordination of the right arm underlies control of bow parameters and quick bow reversals in skilled cello bowing

    Directory of Open Access Journals (Sweden)

    Julius eVerrel

    2014-08-01

    Full Text Available Stringed instrument bowing is a complex coordinative motor skill acquired though years of intense practice. We apply a novel freezing analysis to investigate how movement at different joints contributes to bow transport (movement amplitude, stabilization of bow parameters (angle, velocity during bow movements, and quick reversals of bow direction (acceleration amplitude. Participants were ten advanced or professional cellists (19-32 years, at least 10 years of practice and ten age-matched novice players. Arm and bow movements were recorded using 3D motion capture. To assess how performance depends on articulated use of the right arm, actual data were compared to surrogate data, generated by artificially removing movement at (freezing individual joints in measured arm movements. This analysis showed that both elbow and shoulder significantly contribute to bow transport in experts, while only the shoulder contributed to bow transport in novices. Moreover, experts showed more strongly increased variability of bow parameters and reduced acceleration amplitudes at bow reversals for surrogate compared to actual movement data. This indicates that movement across joints was organized to reduce bow variability and achieve quick bow reversals. Corresponding effects were less pronounced or absent in the novices, in particular for the wrist and elbow. Our results demonstrate the importance of articulated use of the right arm and clarify the contribution of different joints in experts’ bowing performance. Moreover, they support theories of motor control and learning that propose exploitation of biomechanical degrees of freedom, in particular of distal joints, as a critical component in skilled motor performance.

  8. [Bow artefact in B-image sonography].

    Science.gov (United States)

    Bönhof, J A; Stapff, M; Bönhof, B; Kremer, H; Zöllner, N; Linhart, P

    1983-09-01

    Bow-shaped artifacts can often be seen in B-mode-ultrasound examinations. In order to find out the origin of these artifacts, water tank experiments were carried out and compared with in vivo observations. The studies showed that bow-shaped artifacts are caused by beam breadth, and that their shape is influenced by the type of the B-mode-instrument, the adjustment of the machine, and by the shape of the reflector. In vitro and in vivo, bow-shaped artifacts arise at strong reflectors and are visible in regions of low echogeneity. In vivo bow-shaped artifacts may imitate pathological findings such as septa or sludge.

  9. Entropy Generation Across Earth's Bow Shock

    Science.gov (United States)

    Parks, George K.; McCarthy, Michael; Fu, Suiyan; Lee E. s; Cao, Jinbin; Goldstein, Melvyn L.; Canu, Patrick; Dandouras, Iannis S.; Reme, Henri; Fazakerley, Andrew; hide

    2011-01-01

    Earth's bow shock is a transition layer that causes an irreversible change in the state of plasma that is stationary in time. Theories predict entropy increases across the bow shock but entropy has never been directly measured. Cluster and Double Star plasma experiments measure 3D plasma distributions upstream and downstream of the bow shock that allow calculation of Boltzmann's entropy function H and his famous H-theorem, dH/dt O. We present the first direct measurements of entropy density changes across Earth's bow shock. We will show that this entropy generation may be part of the processes that produce the non-thermal plasma distributions is consistent with a kinetic entropy flux model derived from the collisionless Boltzmann equation, giving strong support that solar wind's total entropy across the bow shock remains unchanged. As far as we know, our results are not explained by any existing shock models and should be of interests to theorists.

  10. Energetics of the terrestrial bow shock

    Science.gov (United States)

    Hamrin, Maria; Gunell, Herbert; Norqvist, Patrik

    2017-04-01

    The solar wind is the primary energy source for the magnetospheric energy budget. Energy can enter through the magnetopause both as kinetic energy (plasma entering via e.g. magnetic reconnection and impulsive penetration) and as electromagnetic energy (e.g. by the conversion of solar wind kinetic energy into electromagnetic energy in magnetopause generators). However, energy is extracted from the solar wind already at the bow shock, before it encounters the terrestrial magnetopause. At the bow shock the supersonic solar wind is slowed down and heated, and the region near the bow shock is known to host many complex processes, including the accelerating of particles and the generation of waves. The processes at and near the bow shock can be discussed in terms of energetics: In a generator (load) process kinetic energy is converted to (from) electromagnetic energy. Bow shock regions where the solar wind is decelerated correspond to generators, while regions where particles are energized (accelerated and heated) correspond to loads. Recently, it has been suggested that currents from the bow shock generator should flow across the magnetosheath and connect to the magnetospause current systems [Siebert and Siscoe, 2002; Lopez et al., 2011]. In this study we use data from the Magnetospheric MultiScale (MMS) mission to investigate the energetics of the bow shock and the current closure, and we compare with the MHD simulations of Lopez et al., 2011.

  11. Modeling nonthermal emission from stellar bow shocks

    Science.gov (United States)

    Pereira, V.; López-Santiago, J.; Miceli, M.; Bonito, R.; de Castro, E.

    2016-04-01

    Context. Runaway O- and early B-type stars passing through the interstellar medium at supersonic velocities and characterized by strong stellar winds may produce bow shocks that can serve as particle acceleration sites. Previous theoretical models predict the production of high-energy photons by nonthermal radiative processes, but their efficiency is still debated. Aims: We aim to test and explain the possibility of emission from the bow shocks formed by runaway stars traveling through the interstellar medium by using previous theoretical models. Methods: We applied our model to AE Aurigae, the first reported star with an X-ray detected bow shock, to BD+43 3654, in which the observations failed in detecting high-energy emission, and to the transition phase of a supergiant star in the late stages of its life. Results: From our analysis, we confirm that the X-ray emission from the bow shock produced by AE Aurigae can be explained by inverse Compton processes involving the infrared photons of the heated dust. We also predict low high-energy flux emission from the bow shock produced by BD+43 3654, and the possibility of high-energy emission from the bow shock formed by a supergiant star during the transition phase from blue to red supergiant. Conclusions: Bow shocks formed by different types of runaway stars are revealed as a new possible source of high-energy photons in our neighborhood.

  12. 46 CFR 154.355 - Bow and stern loading piping.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Bow and stern loading piping. 154.355 Section 154.355... Arrangements § 154.355 Bow and stern loading piping. (a) Bow and stern loading piping must: (1) Meet § 154.310... other openings to accommodation, service, or control spaces that face the bow or stern loading area must...

  13. Effect of Buffer Bow Structure in Ship-Ship Collision

    DEFF Research Database (Denmark)

    Yamada, Yasuhira; Endo, Hisayoshi; Pedersen, Preben Terndrup

    2008-01-01

    tankers, the introduction of buffer bulbous bows has been proposed. Relatively soft buffer bows absorb part of the kinetic energy of the striking ship before penetrating the inner hull of the struck vessel. The purpose of the present paper is to verify the effectiveness of a prototype buffer bulbous bow......) and the forward velocity of the struck ship on the collapse mode of the bow of the striking vessel are investigated. Collapse modes, contact forces and energy absorption capabilities of the buffer bows are compared with those of conventional bows....

  14. Entropy generation across Earth's collisionless bow shock.

    Science.gov (United States)

    Parks, G K; Lee, E; McCarthy, M; Goldstein, M; Fu, S Y; Cao, J B; Canu, P; Lin, N; Wilber, M; Dandouras, I; Réme, H; Fazakerley, A

    2012-02-10

    Earth's bow shock is a collisionless shock wave but entropy has never been directly measured across it. The plasma experiments on Cluster and Double Star measure 3D plasma distributions upstream and downstream of the bow shock allowing calculation of Boltzmann's entropy function H and his famous H theorem, dH/dt≤0. The collisionless Boltzmann (Vlasov) equation predicts that the total entropy does not change if the distribution function across the shock becomes nonthermal, but it allows changes in the entropy density. Here, we present the first direct measurements of entropy density changes across Earth's bow shock and show that the results generally support the model of the Vlasov analysis. These observations are a starting point for a more sophisticated analysis that includes 3D computer modeling of collisionless shocks with input from observed particles, waves, and turbulences.

  15. 46 CFR 154.1870 - Bow and stern loading.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Bow and stern loading. 154.1870 Section 154.1870... STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Operations § 154.1870 Bow and stern loading. (a) When the bow or stern loading piping is not in use, the master shall lock closed the shut-off...

  16. Extraction of bowing parameters from violin performance combining motion capture and sensors.

    Science.gov (United States)

    Schoonderwaldt, E; Demoucron, M

    2009-11-01

    A method is described for measurement of a complete set of bowing parameters in violin performance. Optical motion capture was combined with sensors for accurate measurement of the main bowing parameters (bow position, bow velocity, bow acceleration, bow-bridge distance, and bow force) as well as secondary control parameters (skewness, inclination, and tilt of the bow). In addition, other performance features (moments of on/off in bow-string contact, string played, and bowing direction) were extracted. Detailed descriptions of the calculations of the bowing parameters, features, and calibrations are given. The described system is capable of measuring all bowing parameters without disturbing the player, allowing for detailed studies of musically relevant aspects of bow control and coordination of bowing parameters in bowed-string instrument performance.

  17. Plastic bowing of the ribs in children

    Energy Technology Data Exchange (ETDEWEB)

    Caro, P.A.; Borden, S. IV

    1988-06-01

    Four cases of plastic bowing of the ribs are presented. In three patients with Werdnig-Hoffman disease, plastic curvatures were associated with chronic pneumonia and atelectasis. We postulate that intrapulmonary retractive forces can deform ribs thinned by muscular atrophy. In turn, thoracic collapse can perpetuate lobar and segmental atelectasis. In one case of osteogenesis imperfecta without pneumonia, we believe normal muscle forces bent ribs weakened by deficiency of normal cortical architecture.

  18. Coordination in fast repetitive violin-bowing patterns.

    Directory of Open Access Journals (Sweden)

    Erwin Schoonderwaldt

    Full Text Available We present a study of coordination behavior in complex violin-bowing patterns involving simultaneous bow changes (reversal of bowing direction and string crossings (changing from one string to another. Twenty-two violinists (8 advanced amateurs, 8 students with violin as major subject, and 6 elite professionals participated in the experiment. We investigated the influence of a variety of performance conditions (specific bowing patterns, dynamic level, tempo, and transposition and level of expertise on coordination behavior (a.o., relative phase and amplitude and stability. It was found that the general coordination behavior was highly consistent, characterized by a systematic phase lead of bow inclination over bow velocity of about 15° (i.e., string crossings were consistently timed earlier than bow changes. Within similar conditions, a high individual consistency was found, whereas the inter-individual agreement was considerably less. Furthermore, systematic influences of performance conditions on coordination behavior and stability were found, which could be partly explained in terms of particular performance constraints. Concerning level of expertise, only subtle differences were found, the student and professional groups (higher level of expertise showing a slightly higher stability than the amateur group (lower level of expertise. The general coordination behavior as observed in the current study showed a high agreement with perceptual preferences reported in an earlier study to similar bowing patterns, implying that complex bowing trajectories for an important part emerge from auditory-motor interaction.

  19. Coordination in fast repetitive violin-bowing patterns.

    Science.gov (United States)

    Schoonderwaldt, Erwin; Altenmüller, Eckart

    2014-01-01

    We present a study of coordination behavior in complex violin-bowing patterns involving simultaneous bow changes (reversal of bowing direction) and string crossings (changing from one string to another). Twenty-two violinists (8 advanced amateurs, 8 students with violin as major subject, and 6 elite professionals) participated in the experiment. We investigated the influence of a variety of performance conditions (specific bowing patterns, dynamic level, tempo, and transposition) and level of expertise on coordination behavior (a.o., relative phase and amplitude) and stability. It was found that the general coordination behavior was highly consistent, characterized by a systematic phase lead of bow inclination over bow velocity of about 15° (i.e., string crossings were consistently timed earlier than bow changes). Within similar conditions, a high individual consistency was found, whereas the inter-individual agreement was considerably less. Furthermore, systematic influences of performance conditions on coordination behavior and stability were found, which could be partly explained in terms of particular performance constraints. Concerning level of expertise, only subtle differences were found, the student and professional groups (higher level of expertise) showing a slightly higher stability than the amateur group (lower level of expertise). The general coordination behavior as observed in the current study showed a high agreement with perceptual preferences reported in an earlier study to similar bowing patterns, implying that complex bowing trajectories for an important part emerge from auditory-motor interaction.

  20. The heliosphere's interstellar interaction: no bow shock.

    Science.gov (United States)

    McComas, D J; Alexashov, D; Bzowski, M; Fahr, H; Heerikhuisen, J; Izmodenov, V; Lee, M A; Möbius, E; Pogorelov, N; Schwadron, N A; Zank, G P

    2012-06-08

    As the Sun moves through the local interstellar medium, its supersonic, ionized solar wind carves out a cavity called the heliosphere. Recent observations from the Interstellar Boundary Explorer (IBEX) spacecraft show that the relative motion of the Sun with respect to the interstellar medium is slower and in a somewhat different direction than previously thought. Here, we provide combined consensus values for this velocity vector and show that they have important implications for the global interstellar interaction. In particular, the velocity is almost certainly slower than the fast magnetosonic speed, with no bow shock forming ahead of the heliosphere, as was widely expected in the past.

  1. Bow wave and spray dynamics by a wedge

    OpenAIRE

    Wang, Zhaoyuan; Yang, Jianming; Stern, Frederick

    2010-01-01

    Flows around a wedge-shaped bow are simulated with the aim of investigating the wave breaking mechanism and small scale features of ship bow waves. This fluid dynamics video shows the plunging wave breaking process around the wedge including the thin water sheet formation, overturning sheet with surface disturbance, fingering and breaking up into spray, plunging and splashing, and air entrainment.

  2. Marble bowing: comparative studies of three different public building facades

    Science.gov (United States)

    Siegesmund, S.; Ruedrich, J.; Koch, A.

    2008-12-01

    The veneer cladding of the Oeconomicum (OEC, Göttingen), the State Theatre of Darmstadt (STD, Darmstadt) and of the State and University Library (SUB, Göttingen) is characterised by pronounced bowing after a short time of exposure. Direct comparison of bowing data related to measurements from 2000 to 2003 at the SUB clearly show that the amplitude in bowing had significantly increased. The bowing is different in intensity and orientation (concave, convex). The cladding material (Peccia marble, Rosa Estremoz marble and Carrara marble) are different in lattice preferred orientation, grain size distribution and grain interlocking. Depending on the bowing, panels may show cracks mostly initiated at the dowels. The percentage of visible cracks and breakouts increases with the amplitude of bowing except for the STD. Repetitive heating-cooling under dry conditions leads to considerable inelastic residual strain only after the first or second thermal cycle. The residual strain continuously increases again if water is present, whereby the moisture content after a thermal cycle has a certain impact on the decay rate. The water-enhanced thermal dilatation strongly correlates with the deterioration rate obtained from the laboratory bow test. Detailed petrophysical investigations provide evidence that with increasing bowing a decrease of mechanical properties (flexural strength or breaking load at dowel hole) occur. Marble degradation is also connected with the increase in porosity and a general shift of the maximum pore radii to larger pore sizes. On-site damage analyses were combined with laboratory tests of the bowing potential to constrain factors that may influence the risk failure. The experimental bowing data clearly demonstrate that after 40 heating cycles combined with the effect of moisture a certain impact on the decay rate is observed. In the case of demounted panels the bowing tests show that already strongly deformed panels from the building exhibit a lower

  3. Radiographic characteristics of lower-extremity bowing in children.

    Science.gov (United States)

    Cheema, Jugesh I; Grissom, Leslie E; Harcke, H Theodore

    2003-01-01

    Lower-extremity bowing is common in infants and children and can result from a variety of conditions. At radiography, developmental bowing shows varus angulation centered at the knee, "metaphyseal beaking," thickening of the medial tibial cortices, and tilted ankle joints. Tibia vara (Blount disease) demonstrates genu varum and depression of the proximal tibia medially. Congenital bowing manifests as posteromedial bowing with cortical thickening along the concavity of the curvature and, in some cases, diaphyseal broadening. In rickets, radiographic changes occur primarily at sites of rapid growth and are predominantly metaphyseal, with widening of the zone of provisional calcification. Achondroplasia is characterized by shortening and thickening of the long bones with metaphyseal flaring and cupping. In neurofibromatosis, there may be anterolateral bowing of the tibia, and there is often focal narrowing and intramedullary sclerosis or cystic change at the apex of the angulation. The tibia is typically involved at the junction of the middle and distal thirds. Osteogenesis imperfecta demonstrates bowing from softening due to osteoporosis and multiple fractures and typically involves the entire skeleton. In camptomelic dysplasia, lower-extremity bowing is associated with a short trunk, short limbs, and deficiencies in pelvic bone development. Recognition of these pathologic conditions is important for differentiating those that will resolve spontaneously from those that require surgery or other treatment. Copyright RSNA, 2003

  4. H2 emission from non-stationary magnetized bow shocks

    Science.gov (United States)

    Tram, L. N.; Lesaffre, P.; Cabrit, S.; Gusdorf, A.; Nhung, P. T.

    2018-01-01

    When a fast moving star or a protostellar jet hits an interstellar cloud, the surrounding gas gets heated and illuminated: a bow shock is born that delineates the wake of the impact. In such a process, the new molecules that are formed and excited in the gas phase become accessible to observations. In this paper, we revisit models of H2 emission in these bow shocks. We approximate the bow shock by a statistical distribution of planar shocks computed with a magnetized shock model. We improve on previous works by considering arbitrary bow shapes, a finite irradiation field and by including the age effect of non-stationary C-type shocks on the excitation diagram and line profiles of H2. We also examine the dependence of the line profiles on the shock velocity and on the viewing angle: we suggest that spectrally resolved observations may greatly help to probe the dynamics inside the bow shock. For reasonable bow shapes, our analysis shows that low-velocity shocks largely contribute to H2 excitation diagram. This can result in an observational bias towards low velocities when planar shocks are used to interpret H2 emission from an unresolved bow. We also report a large magnetization bias when the velocity of the planar model is set independently. Our 3D models reproduce excitation diagrams in BHR 71 and Orion bow shocks better than previous 1D models. Our 3D model is also able to reproduce the shape and width of the broad H2 1-0S(1) line profile in an Orion bow shock (Brand et al. 1989).

  5. Structural changes in cuticles on violin bow hair caused by wear.

    Science.gov (United States)

    Yamamoto, Tomoko; Sugiyama, Shigeru

    2010-01-01

    A bow with horse tail hair is used to play the violin. New and worn-out bow hairs were observed by atomic force microscopy. The cuticles of the new bow hair were already damaged by bleach and delipidation, however the worn-out bow hairs were much more damaged and broken off by force, which relates to wearing out.

  6. Downsized Bow-Tie Antenna with Folded Elements

    Science.gov (United States)

    Nagatoshi, Mio; Tanaka, Shingo; Horiuchi, Satoru; Morishita, Hisashi

    It has been reported that by adding two folded elements, bow-tie antenna can be miniaturized, but the antenna has VSWR degradation problem. In this paper, the details of the VSWR degradation are investigated and the physical mechanism of the degradation is clarified. The best position for folded element is also shown. Moreover, the bow-tie antenna is bent in half in order to realize more size reduction. When the two folded elements are added to the half bent bow-tie antenna, the lowest operation frequency goes down and the proposed antenna can be more downsized than the previous proposed antenna. The gain is slightly lower than that of the previous model, however, the antenna area is reduced from 31%, which is the antenna area ratio of privious proposed antenna and conventional bow-tie antenna, to 19%. The bandwidth of 92% is obtained for VSWR≤2.

  7. Femoral bowing plane adaptation to femoral anteversion

    Directory of Open Access Journals (Sweden)

    Alp Akman

    2017-01-01

    Full Text Available Background: Femoral bowing plane (FBP is the unattended subject in the literature. More over the femoral shaft with its bowing is neglected in established anteversion determination methods. There is limited information about the relationship between FBP and anteversion. Thus we focused on this subject and hypothesized that there could be an adaptation of FBP to anteversion. Materials and Methods: FBP is determined on three-dimensional solid models derived from the left femoral computerized tomography data of 47 patients which were taken before for another reason and comparatively evaluated with anteversion. There were 20 women and 27 men. The mean age of patients was 56 years (range 21-84 years. Results: The anteversion values were found as the angle between a distal condylar axis (DCA and femoral neck anteversion axis (FNAA along an imaginary longitudinal femoral axis (LFA in the true cranio-caudal view. The FBP was determined as a plane that passes through the centre-points of three pre-determinated sections on the femoral shaft. The angles between DCA, FNAA and FBP were comparatively evaluated. The independent samples t-test was used for statistical analysis. At the end, it was found that FBP lies nearly perpendicular to the anteversion axis for the mean of our sample which is around 89° in females and 93° in males (range 78-102°. On the other hand, FBP does not lie close to the sagittal femoral plane (SFP; instead, there is an average 12.5° external rotation relative to the SFP. FBP is correlated well with anteversion in terms of FBP inclination from SFP and femoral torsion (i.e., angle between FBP and femoral neck anteversion axis (P0 < 0.001; r = 0.680 and r = −0.682, respectively. Combined correlation is perfect (R[2] = 1 as the FBP, SFP, and posterior femoral plane forms a triangle in the cranio-caudal view. Conclusions: We found that FBP adapts to anteversion. As FBP lies close to perpendicularity for the mean, femoral component

  8. Mesoscale Surface Pressure and Temperature Features Associated with Bow Echoes

    Science.gov (United States)

    2010-01-01

    contain several bowing segments. These multiple segments could occur at the same time and be located within the same bow, such as the serial derecho ...Examination of derecho environments using proximity soundings. Wea. Forecasting, 16, 329–342. Fovell, R. G., 2002: Upstream influence of numerically...Se- vere Local Storms, Hyannis, MA, Amer. Meteor. Soc., 4.6. Johns, R. H., and W. D. Hirt, 1987: Derechos : Widespread con- vectively induced

  9. Congenital anterolateral tibial bowing and polydactyly: a case report

    Directory of Open Access Journals (Sweden)

    Lemire Edmond G

    2007-07-01

    Full Text Available Abstract Congenital anterolateral bowing of the tibia is a rare deformity that may lead to pseudarthrosis and risk of fracture. This is commonly associated with neurofibromatosis type 1. In this report, we describe a 15-month old male with congenital anterolateral bowing of the right tibia and associated hallux duplication. This is a distinct entity with a generally favourable prognosis that should not be confused with other conditions such as neurofibromatosis type 1. Previously published cases are reviewed.

  10. Whistler waves at the Earth bow shock

    Science.gov (United States)

    Wei, Hanying; Russell, Christopher T.; Strangeway, Rorbert J.; Schwartz, Steve J.; An, Xin; Fischer, David; Le Contel, Olivier; Argall, Matthew; Paterson, William R.; Torbert, Roy B.

    2017-04-01

    The Magnetospheric Multiscale (MMS) spacecraft, with their state-of-the-art plasma and field instruments onboard, allow us to investigate electromagnetic waves at the bow shock and their association with small-scale disturbances in the shocked plasmas. Understanding these waves could improve our knowledge on the heating of electrons and ions across the shock ramp and the energy dissipation of supercritical shocks. We have found broad-band and narrow band waves across the shock ramp and slightly downstream. The broad-band waves propagate obliquely to the magnetic field direction and have frequencies up to the electron cyclotron frequency. Simultaneously, the electrons have quite disturbed velocities and are anisotropic in velocity space, leading to multiple possible instabilities, such as kinetic cross-field streaming instability, low-hybrid drift instability, etc. In the same region with the broad-band wave, there are narrow-band waves at a few hundred Hertz with durations under a second. These waves are right-handed circularly polarized and propagate along the magnetic field lines. The broad-band waves are only observed at the shock ramp, but the narrow-band waves are observed more frequently further downstream in the magnetosheath. Both wave types are likely to be whistler mode with different generation mechanisms. In this paper, we examine the electric and magnetic fields of these waves, as well as the plasma observations to understand the wave generation and their effects on the shock and magnetosheath plasmas.

  11. X-ray study of bow shocks in runaway stars

    Science.gov (United States)

    De Becker, M.; del Valle, M. V.; Romero, G. E.; Peri, C. S.; Benaglia, P.

    2017-11-01

    Massive runaway stars produce bow shocks through the interaction of their winds with the interstellar medium, with the prospect for particle acceleration by the shocks. These objects are consequently candidates for non-thermal emission. Our aim is to investigate the X-ray emission from these sources. We observed with XMM-Newton a sample of five bow shock runaways, which constitutes a significant improvement of the sample of bow shock runaways studied in X-rays so far. A careful analysis of the data did not reveal any X-ray emission related to the bow shocks. However, X-ray emission from the stars is detected, in agreement with the expected thermal emission from stellar winds. On the basis of background measurements we derive conservative upper limits between 0.3 and 10 keV on the bow shocks emission. Using a simple radiation model, these limits together with radio upper limits allow us to constrain some of the main physical quantities involved in the non-thermal emission processes, such as the magnetic field strength and the amount of incident infrared photons. The reasons likely responsible for the non-detection of non-thermal radiation are discussed. Finally, using energy budget arguments, we investigate the detectability of inverse Compton X-rays in a more extended sample of catalogued runaway star bow shocks. From our analysis we conclude that a clear identification of non-thermal X-rays from massive runaway bow shocks requires one order of magnitude (or higher) sensitivity improvement with respect to present observatories.

  12. Venus bow shocks at unusually large distances from the planet

    Science.gov (United States)

    Steinolfson, R. S.; Cable, S.

    1993-01-01

    Recent analysis of data from the Pioneer Venus Orbiter (PVO) has shown that the bow shock often travels to unusually large distances from the planet when the solar wind magnetosonic Mach number is near unity. We suggest that distant bow shocks can be explained as an integral part of the response of the global solar wind/Venus interaction to the anomalous local solar wind conditions that existed during the time of these observations. The lower-than-normal plasma beta and magnetosonic Mach number are in a parameter regime for which the usual fast-mode bow shock close to the planet may not provide the necessary compression and deflection of the solar wind. Using MHD simulations we show that, for these conditions, the usual fast shock is replaced by a bow shock consisting of an intermediate shock near the Sun-Venus line and a fast shock at large distances from the Sun-Venus line. This composite bow shock propagates upstream away from the planet at a low speed and appears to be approaching a new equilibrium stand-off location at a large distance from the planet.

  13. Bow and Oblique Shock Formation in Soap Film

    Science.gov (United States)

    Kim, Ildoo; Mandre, Shreyas; Sane, Aakash

    2015-11-01

    In recent years, soap films have been exploited primarily to approximate two-dimensional flows while their three-dimensional character is relatively unattended. An example of the three-dimensional character of the flow in a soap film is the observed Marangoni shock wave when the flow speed exceeds the wave speed. In this study, we investigated the formation of bow and oblique shocks in soap films generated by wedges with different deflection angles. When the wedge deflection angle is small and the film flows fast, oblique shocks are observed. When the oblique shock cannot exists, bow shock is formed upstream the wedge. We characterized the oblique shock angle as a function of the wedge deflection angle and the flow speed, and we also present the criteria for transition between bow and oblique Marangoni shocks in soap films.

  14. CONGENITAL POSTEROMEDIAL BOWING OF THE TIBIA: REPORT OF 2 CASES

    Directory of Open Access Journals (Sweden)

    Ângela Isabel Miguel Dias

    2017-01-01

    Comments: Posteromedial bowing of the tibia is a rare entity, with few cases reported in literature. Its true incidence remains unknown. It implies differential diagnosis with the tibial congenital pseudarthrosis, usually related to neurofibromatosis. Most often its treatment is conservative, because it tends to resolve spontaneously (mostly under 8 years without any clinical consequences. Our aim is to alert pediatricians to establish the possibility of this clinical entity when dealing with tibial bowing, minimizing parental anxiety resulting from it. Nevertheless we emphasize the importance of evaluation by an orthopedist as there are clinical situations in which diagnosis may not be as evident.

  15. 76 FR 13666 - Pitney Bowes, Inc., Mailing Solutions Management, Global Engineering Group, Including On-Site...

    Science.gov (United States)

    2011-03-14

    ... Employment and Training Administration Pitney Bowes, Inc., Mailing Solutions Management, Global Engineering... Solutions Management Division, Engineering Quality Assurance, Shelton, Connecticut. The Department's Notice... firm worker group should read: Pitney Bowes, Inc., Mailing Solutions Management, Global Engineering...

  16. Analysis of the Giacobini-Zinner bow wave

    Energy Technology Data Exchange (ETDEWEB)

    Smith, E.J.; Slavin, J.A.; Bame, S.J.; Thomsen, M.F.; Cowley, S.W.H.; Richardson, I.G.; Hovestadt, D.; Ipavich, F.M.; Ogilvie, K.W.; Coplan, M.A.

    1986-01-01

    The cometary bow wave of P/Giacobini-Zinner has been analyzed using the complete set of ICE field and particle observations to determine if it is a shock. Changes in the magnetic field and plasma flow velocities from upstream to downstream have been analyzed to determine the direction of the normal and the propagation velocity of the bow wave. The velocity has then been compared with the fast magnetosonic wave speed upstream to derive the Mach number and establish whether it is ''supersonic'', i.e., a shock, or ''subsonic,'' i.e., a large amplitude wave. The various measurements have also been compared with values derived from a Rankine-Hugoniot analysis. The results indicate that, inbound, the bow wave is a shock with M = 1.5. Outbound, a subsonic mach number is obtained, however, arguments are presented that the bow wave is also likely to be a shock at this location. 11 refs., 4 figs., 2 tabs.

  17. Hierarchical modularity of nested bow-ties in metabolic networks

    Directory of Open Access Journals (Sweden)

    Luo Jian-Hua

    2006-08-01

    Full Text Available Abstract Background The exploration of the structural topology and the organizing principles of genome-based large-scale metabolic networks is essential for studying possible relations between structure and functionality of metabolic networks. Topological analysis of graph models has often been applied to study the structural characteristics of complex metabolic networks. Results In this work, metabolic networks of 75 organisms were investigated from a topological point of view. Network decomposition of three microbes (Escherichia coli, Aeropyrum pernix and Saccharomyces cerevisiae shows that almost all of the sub-networks exhibit a highly modularized bow-tie topological pattern similar to that of the global metabolic networks. Moreover, these small bow-ties are hierarchically nested into larger ones and collectively integrated into a large metabolic network, and important features of this modularity are not observed in the random shuffled network. In addition, such a bow-tie pattern appears to be present in certain chemically isolated functional modules and spatially separated modules including carbohydrate metabolism, cytosol and mitochondrion respectively. Conclusion The highly modularized bow-tie pattern is present at different levels and scales, and in different chemical and spatial modules of metabolic networks, which is likely the result of the evolutionary process rather than a random accident. Identification and analysis of such a pattern is helpful for understanding the design principles and facilitate the modelling of metabolic networks.

  18. Small Arms of the Scythians. On the Time of Sigmoid Bow Appearance in Eastern Europe

    Directory of Open Access Journals (Sweden)

    Lukyashko Sergey Ivanovich

    2015-12-01

    Full Text Available Horse archers well-known in the ancient world used composite sigmoid bows for shooting (archery, the specific constructive features of which have been studied by the researchers. This type of a bow was convergently formed in Eastern China in the middle of the 2nd millennium B.C. and in the North Caucasus in the middle of the 4th millennium B.C. It gets transferred to the Northern Black Sea Region by the Scythians in the late 7th - early 6th centuries B.C. that resulted in the dramatic transformation of arrowheads’ types. The Greeks became aware of this weapon in the last third of the 6th century B.C. Bows can be divided into simple and complex ones. The simple bows are made from one solid bar, while the complex bows are made of several layers of different wood species. Composite bows are constructed from a few consequently connected bars. These types also include a reinforced bow – the bow springing qualities of which are reinforced by bone or tendon plates. Since the ancient masters combined different production methods, the definition of a composite reinforced bow can be found in the literature. European small arms development was focused on improving a simple bow. The strength of such bow was achieved by its size. However, massive bows are unsuitable for firing from a horse. Therefore, in cultures associated with the development of riding the search of methods of bow strength increase at the condition of reducing its size, was going on. In Asia, the focus was made on the material rather than shoulders design. As a result, complex composite bows appear in the East, which were made from several pieces of wood, connected with the central part of the handle at an angle. After the appearance of the Scythians in the middle East the angular design of bows was replaced by a sigmoid shape (scythicus acrus.

  19. Magnetic field fluctuations across the Earth’s bow shock

    Directory of Open Access Journals (Sweden)

    A. Czaykowska

    Full Text Available We present a statistical analysis of 132 dayside (LT 0700-1700 bow shock crossings of the AMPTE/IRM spacecraft. We perform a superposed epoch analysis of low frequency, magnetic power spectra some minutes up-stream and downstream of the bow shock. The events are devided into categories depending on the angle θBn between bow shock normal and interplanetary magnetic field, and on plasma-β. In the foreshock upstream of the quasi-parallel bow shock, the power of the magnetic fluctuations is roughly 1 order of magnitude larger (δB ~ 4 nT for frequencies 0.01–0.04 Hz than upstream of the quasi-perpendicular shock. There is no significant difference in the magnetic power spectra upstream and downstream of the quasi-parallel bow shock; only at the shock itself, is the magnetic power enhanced by a factor of 4. This enhancement may be due to either an amplification of convecting upstream waves or to wave generation at the shock interface. On the contrary, downstream of the quasi-perpendicular shock, the magnetic wave activity is considerably higher than upstream. Down-stream of the quasi-perpendicular low-β bow shock, we find a dominance of the left-hand polarized component at frequencies just below the ion-cyclotron frequency, with amplitudes of about 3 nT. These waves are identified as ion-cyclotron waves, which grow in a low-β regime due to the proton temperature anisotropy. We find a strong correlation of this anisotropy with the intensity of the left-hand polarized component. Downstream of some nearly perpendicular (θBn ≈ 90° high-β crossings, mirror waves are identified. However, there are also cases where the conditions for mirror modes are met downstream of the nearly perpendicular shock, but no mirror waves are observed.

    Key words. Interplanetary physics (plasma waves and turbulence – Magnetospheric physics (magnetosheath; plasma waves and

  20. Magnetic field fluctuations across the Earth’s bow shock

    Directory of Open Access Journals (Sweden)

    A. Czaykowska

    2001-03-01

    Full Text Available We present a statistical analysis of 132 dayside (LT 0700-1700 bow shock crossings of the AMPTE/IRM spacecraft. We perform a superposed epoch analysis of low frequency, magnetic power spectra some minutes up-stream and downstream of the bow shock. The events are devided into categories depending on the angle θBn between bow shock normal and interplanetary magnetic field, and on plasma-β. In the foreshock upstream of the quasi-parallel bow shock, the power of the magnetic fluctuations is roughly 1 order of magnitude larger (δB ~ 4 nT for frequencies 0.01–0.04 Hz than upstream of the quasi-perpendicular shock. There is no significant difference in the magnetic power spectra upstream and downstream of the quasi-parallel bow shock; only at the shock itself, is the magnetic power enhanced by a factor of 4. This enhancement may be due to either an amplification of convecting upstream waves or to wave generation at the shock interface. On the contrary, downstream of the quasi-perpendicular shock, the magnetic wave activity is considerably higher than upstream. Down-stream of the quasi-perpendicular low-β bow shock, we find a dominance of the left-hand polarized component at frequencies just below the ion-cyclotron frequency, with amplitudes of about 3 nT. These waves are identified as ion-cyclotron waves, which grow in a low-β regime due to the proton temperature anisotropy. We find a strong correlation of this anisotropy with the intensity of the left-hand polarized component. Downstream of some nearly perpendicular (θBn ≈ 90° high-β crossings, mirror waves are identified. However, there are also cases where the conditions for mirror modes are met downstream of the nearly perpendicular shock, but no mirror waves are observed.Key words. Interplanetary physics (plasma waves and turbulence – Magnetospheric physics (magnetosheath; plasma waves and instabilities

  1. Hot flow anomaly observed at Jupiter's bow shock

    Science.gov (United States)

    Valek, P. W.; Thomsen, M. F.; Allegrini, F.; Bagenal, F.; Bolton, S.; Connerney, J.; Ebert, R. W.; Gladstone, R.; Kurth, W. S.; Levin, S.; Louarn, P.; Mauk, B.; McComas, D. J.; Pollock, C.; Reno, M.; Szalay, J. R.; Weidner, S.; Wilson, R. J.

    2017-08-01

    A Hot Flow Anomaly (HFA) is created when an interplanetary current sheet interacts with a planetary bow shock. Previous studies have reported observing HFAs at Earth, Mercury, Venus, Mars, and Saturn. During Juno's approach to Jupiter, a number of its instruments operated in the solar wind. Prior to crossing into Jupiter's magnetosphere, Juno observed an HFA at Jupiter for the first time. This Jovian HFA shares most of the characteristics of HFAs seen at other planets. The notable exception is that the Jovian HFA is significantly larger than any HFA seen before. With an apparent size greater than 2 × 106 km the Jovian HFA is orders of magnitude larger than those seen at the other planets. By comparing the size of the HFAs at the other planets with the Jovian HFA, we conclude that HFAs size scales with the size of planetary bow shocks that the interplanetary current sheet interacts with.

  2. Bowing to the Dharma: Japanese Buddhist Women Leaders & Healers

    Directory of Open Access Journals (Sweden)

    Paula Arai

    2017-11-01

    Full Text Available The prodigious stream of Japanese Buddhist women in roles of leadership and healing extends the length of Japanese Buddhist history. This article will highlight the transformative power of bowing that helped galvanize Sōtō Zen nuns on the eve of the twentieth century and feature twentieth-century leaders who institutionalized their disciplined commitments. It will also offer a window into the creative healing practices that characterizes women’s activity in the home.

  3. Arctic Bowyery – The Use of Compression Wood in Bows in the Subarctic and Arctic Regions of Eurasia and America

    Directory of Open Access Journals (Sweden)

    Marcus Lepola

    2015-06-01

    Full Text Available This paper is a study of the traditional use of a special kind of wood in bow construction in Eurasia and North America. This special kind of wood, called compression wood and coming from coniferous trees, has unique qualities that makes it suitable for bow construction. Bows made using this special wood have been referred to as Finno-Ugric bows, Sámi bows, Two-Wood bows and Eurasia laminated bows. These bows appear to have developed from archaic forms of compression wood self bows that were made from a single piece of wood. Recently features similar to the Eurasian compression wood bows have been discovered in bows originating from Alaska, and the use of compression wood for bow manufacture has been known to some Canadian Inuit groups. This paper addresses the origin and possible diffusion pattern of this innovation in bow technology in Eurasia and suggests a timeframe and a possible source for the transfer of this knowledge to North America. This paper also discusses the role of the Asiatic composite bow in the development of bows in Eurasia.

  4. Arctic Bowyery – the Use of Compression Wood in Bows in the Subarctic and Arctic Regions of Eurasia and America

    Directory of Open Access Journals (Sweden)

    Marcus Lepola

    2015-06-01

    Full Text Available This paper is a study of the traditional use of a special kind of wood in bow construction in Eurasia and North America. This special kind of wood, called compression wood and coming from coniferous trees, has unique qualities that makes it suitable for bow construction. Bows made using this special wood have been referred to as Finno-Ugric bows, Sámi bows, Two-Wood bows and Eurasia laminated bows. These bows appear to have developed from archaic forms of compression wood self bows that were made from a single piece of wood. Recently features similar to the Eurasian compression wood bows have been discovered in bows originating from Alaska, and the use of compression wood for bow manufacture has been known to some Canadian Inuit groups. This paper addresses the origin and possible diffusion pattern of this innovation in bow technology in Eurasia and suggests a timeframe and a possible source for the transfer of this knowledge to North America. This paper also discusses the role of the Asiatic composite bow in the development of bows in Eurasia.

  5. PLANETARY EMBRYO BOW SHOCKS AS A MECHANISM FOR CHONDRULE FORMATION

    Energy Technology Data Exchange (ETDEWEB)

    Mann, Christopher R.; Boley, Aaron C. [Department of Physics and Astronomy University of British Columbia Vancouver, BC V6T 1Z1 (Canada); Morris, Melissa A. [Physics Department State University of New York at Cortland Cortland, NY 13045 (United States)

    2016-02-20

    We use radiation hydrodynamics with direct particle integration to explore the feasibility of chondrule formation in planetary embryo bow shocks. The calculations presented here are used to explore the consequences of a Mars-size planetary embryo traveling on a moderately excited orbit through the dusty, early environment of the solar system. The embryo’s eccentric orbit produces a range of supersonic relative velocities between the embryo and the circularly orbiting gas and dust, prompting the formation of bow shocks. Temporary atmospheres around these embryos, which can be created via volatile outgassing and gas capture from the surrounding nebula, can non-trivially affect thermal profiles of solids entering the shock. We explore the thermal environment of solids that traverse the bow shock at different impact radii, the effects that planetoid atmospheres have on shock morphologies, and the stripping efficiency of planetoidal atmospheres in the presence of high relative winds. Simulations are run using adiabatic and radiative conditions, with multiple treatments for the local opacities. Shock speeds of 5, 6, and 7 km s{sup −1} are explored. We find that a high-mass atmosphere and inefficient radiative conditions can produce peak temperatures and cooling rates that are consistent with the constraints set by chondrule furnace studies. For most conditions, the derived cooling rates are potentially too high to be consistent with chondrule formation.

  6. Dependence of sound characteristics on the bowing position in a violin

    Science.gov (United States)

    Roh, YuJi; Kim, Young H.

    2014-12-01

    A quantitative analysis of violin sounds produced for different bowing positions over the full length of a violin string has been carried out. An automated bowing machine was employed in order to keep the bowing parameters constant. A 3-dimensional profile of the frequency spectrum was introduced in order to characterize the violin's sound. We found that the fundamental frequency did not change for different bowing positions, whereas the frequencies of the higher harmonics were different. Bowing the string at 30 mm from the bridge produced musical sounds. The middle of the string was confirmed to be a dead zone, as reported in previous works. In addition, the quarter position was also found to be a dead zone. Bowing the string 90 mm from the bridge dominantly produces a fundamental frequency of 864 Hz and its harmonics.

  7. Numerical Study on the Effect of Buffer Bow Structure in Ship-to-ship Collisions

    DEFF Research Database (Denmark)

    Yamada, Yasuhira; Endo, Hisayoshi; Pedersen, Preben Terndrup

    2005-01-01

    A disastrous oil spill from a struck oil tanker has become one of the major problems in view of conservation of maritime environment. So far double hulls (D/H) have been introduced to reduce the consequences of collision and grounding events In order to further reduce the oil spill from struck oil...... tankers, the introduction of buffer bulbous bows has been proposed. Relatively soft buffer bows absorb part of the kinetic energy of the striking ship before penetrating the inner hull of the struck vessel. The purpose of the present paper is to verify the effectiveness of a prototype buffer bulbous bow......) and the forward velocity of the struck ship on the collapse mode of the bow of the striking vessel are investigated. Collapse modes, contact forces and energy absorption capabilities of the buffer bows are compared with those of conventional bows....

  8. Towards a generalized friction controller: from the bowed string to Unusual Musical Instruments

    DEFF Research Database (Denmark)

    Serafin, Stefania; Young, Diana

    2017-01-01

    We present case studies of unusual instruments that share the same excitation mechanism as that of the bowed string. The musical saw, Tibetan singing bow, glass harmonica, and bowed cymbal all produce sound by rubbing a hard object on the surface of the instrument. For each, we discuss the design...... of its physical model and present a means for expressively controlling it. Finally, we propose a new kind of generalized friction controller to be used in all these examples....

  9. Trends and correlation analysis in diagnosing turbine rotor bow

    Directory of Open Access Journals (Sweden)

    Tomasz GAŁKA

    2009-01-01

    Full Text Available Permanent rotor bow in a steam turbine is a serious failure which usually demands a time-consuming and costly repair. Its vibration-related symptoms are not specific and qualitative diagnosis typically has to employ results obtained during transients.In a 230 MW power steam turbine, gradual dynamic behavior deterioration was observed, immediately after commissioning. Increase of the fundamental component of rear intermediate-pressure turbine bearing vertical vibration was detected, with the time constant of the order of months. Permanent rotor bow, exceeding 200 m, turned out to be the cause. Rotor repair resulted in a dramatic improvement of dynamic behavior, which, however, soon began to deteriorate again. Vibration spectra had been detected in the off-line mode since commissioning, which allowed to determine vibration time histories.Vibration trends analysis does not provide sufficient information to determine root cause, but allows for eliminating a number of possible malfunctions that give similar symptoms. In particular, the possibility of a sudden random-type damage due to human error is eliminated, which in fact is the most common cause of a permanent bow.Analysis of vibration amplitude correlation between vertical and axial directions reveals very strong correlation between fundamental components in the turbine under consideration, as well in the other one, in which similar failure has been observed. Third unit of the same type, apart from qualitatively different vibration trends, is characterized by correlation factors lower by a few times.This particular case is indicative of the importance of evolutionary symptoms (vibration amplitude time dependence and increase rate, as well as correlation factors in qualitative diagnosis. Such symptoms can be very useful in distinguishing between possible failures which result in similar changes of machine vibration behavior.

  10. Modeling of the Archery Bow and Arrow Vibrations

    Directory of Open Access Journals (Sweden)

    I. Zaniewski

    2009-01-01

    Full Text Available Vibration processes in the compound and open kinematical chain with an external link, as a model of an archery bow and arrow system, are evaluated. A mechanical and mathematical model of bend oscillations of the system during accelerate motion of the external link is proposed. Correlation between longitudinal acceleration and natural frequencies is obtained. There are recommendations regarding determination of virtual forms to study arrow vibrations and buckling. The models and methods have been adapted for realization into the engineering method using well-known mathematical software packages.

  11. Effective Maxillary Protraction with Tandem Traction Bow Appliance

    Directory of Open Access Journals (Sweden)

    Pravin Kumar S Marure

    2014-01-01

    Full Text Available Tandem traction bow appliance (TTBA promotes patient compliance, because it is more esthetic and comfortable than extraoral appliances. TTBA should be used only in case where maxillary deficiency and normal mandible is present. Advantages of it includes good oral hygiene, early treatment of any Class III malocclusion, optimal retention, distribution of the forces for protraction to all maxillary teeth, free mandibular movement. It can be used in conjunction with fixed appliances if necessary. This paper includes two case reports. The treatment results in both the cases demonstrated significant skeletal and dental response to TTBA therapy. Skeletal change was primarily a result of anterior movement of the maxilla.

  12. Lunar Surface Potential Increases during Terrestrial Bow Shock Traversals

    Science.gov (United States)

    Collier, Michael R.; Stubbs, Timothy J.; Hills, H. Kent; Halekas, Jasper; Farrell, William M.; Delory, Greg T.; Espley, Jared; Freeman, John W.; Vondrak, Richard R.; Kasper, Justin

    2009-01-01

    Since the Apollo era the electric potential of the Moon has been a subject of interest and debate. Deployed by three Apollo missions, Apollo 12, Apollo 14 and Apollo 15, the Suprathermal Ion Detector Experiment (SIDE) determined the sunlit lunar surface potential to be about +10 Volts using the energy spectra of lunar ionospheric thermal ions accelerated toward the Moon. We present an analysis of Apollo 14 SIDE "resonance" events that indicate the lunar surface potential increases when the Moon traverses the dawn bow shock. By analyzing Wind spacecraft crossings of the terrestrial bow shock at approximately this location and employing current balancing models of the lunar surface, we suggest causes for the increasing potential. Determining the origin of this phenomenon will improve our ability to predict the lunar surface potential in support of human exploration as well as provide models for the behavior of other airless bodies when they traverse similar features such as interplanetary shocks, both of which are goals of the NASA Lunar Science Institute's Dynamic Response of the Environment At the Moon (DREAM) team.

  13. Bow Shock Leads the Way for a Speeding Hot Jupiter

    Science.gov (United States)

    Kohler, Susanna

    2015-09-01

    As hot Jupiters whip around their host stars, their speeds can exceed the speed of sound in the surrounding material, theoretically causing a shock to form ahead of them. Now, a study has reported the detection of such a shock ahead of transiting exoplanet HD 189733b, providing a potential indicator of the remarkably strong magnetic field of the planet.Rushing PlanetsDue to their proximity to their hosts, hot Jupiters move very quickly through the stellar wind and corona surrounding the star. When this motion is supersonic, the material ahead of the planet can be compressed by a bow shock and for a transiting hot Jupiter, this shock will cross the face of the host star in advance of the planets transit.In a recent study, a team of researchers by Wilson Cauley of Wesleyan University report evidence of just such a pre-transit. The teams target is exoplanet HD 189733b, one of the closest hot Jupiters to our solar system. When the authors examined high-resolution transmission spectra of this system, they found that prior to the optical transit of the planet, there was a large dip in the transmission of the first three hydrogen Balmer lines. This could well be the absorption of an optically-thick bow shock as it moves past the face of the star.Tremendous MagnetismOperating under this assumption, the authors create a model of the absorption expected from a hot Jupiter transiting with a bow shock ahead of it. Using this model, they show that a shock leading the planet at a distance of 12.75 times the planets radius reproduces the key features of the transmission spectrum.This stand-off distance is surprisingly large. Assuming that the location of the bow shock is set by the point where the planets magnetospheric pressure balances the pressure of the stellar wind or corona that it passes through, the planetary magnetic field would have to be at least 28 Gauss. This is seven times the strength of Jupiters magnetic field!Understanding the magnetic fields of exoplanets is

  14. Effect of Body Structure on Skill Formation in a Force Precision Task Mimicking Cello Bowing Movement

    Science.gov (United States)

    Ogihara, Naomichi; Yamazaki, Nobutoshi

    To elucidate the skill formation mechanism in a complex force precision task mimicking cello bowing movements, three-dimensional joint orientations and changes in bowing force are measured for 2 novice and 2 expert subjects. A rigid link model of the human upper limb is constructed in order to calculate changes in joint moment, potential energy and structural inductivity of motion during bowing, and the motions are compared kinetically. Results show that the novices generate low-in-potential energy bowing motion, but not suitable for skillful control of the bow. In contrast, the experts can fulfill a task requirement by skillfully coordinating the musculo-skeletal system, but the motion is not easy as that of the novices. It is suggested that the transition from a novice to an expert may be difficult due to the ease in the initially generated motion, which obstructs the search for the optimal skillful motion.

  15. Unequal outer and inner bow configurations: comparing 2 asymmetric headgear systems.

    Science.gov (United States)

    Brosh, Tamar; Portal, Schay; Sarne, Ofer; Vardimon, Alexander D

    2005-07-01

    Asymmetric headgear is used when different molar distalization forces (MDF) are needed on the right and left sides of the jaw to correct a Class II molar relationship. We investigated 2 asymmetric headgear configurations, the outer-bow and the inner-bow, on cervical-pull headgear. In the first configuration, 5 hooks were soldered on 1 side of the outer bow at 10-mm intervals, making this side shorter; in the other, 4 stops (1.5 mm) were added to 1 side of the inner bow, making this side longer. The right and left MDF and the extraoral force (EF) were measured simultaneously with 2 fork transducers and a testing machine, respectively. A 40-mm difference between the long and short outer bows resulted in a 2.17-fold greater MDF on the long-side molar (7:3 ratio). The 3-4 stop configuration provided the optimal inner-bow arrangement, with stop/no-stop MDF ratios of 7:3 and 10:0, respectively, at 10 N EF. At low-to-medium EF levels, a unilateral MDF developed on the stop side with zero MDF on the no-stop side. The sum of the right and left MDF nearly equaled the EF in the outer-bow asymmetry and was 60% in the inner-bow setting; this suggests strong lateral forces in the latter. Clinically, for a bilateral unequal Class II relationship, the system of choice is outer-bow asymmetric headgear. For a unilateral Class II relationship with 1 side in a Class I molar relationship (Class II subdivision), inner-bow asymmetric headgear is recommended.

  16. Curvature and bow of bulk GaN substrates

    Energy Technology Data Exchange (ETDEWEB)

    Foronda, Humberto M.; Young, Erin C.; Robertson, Christian A.; Speck, James S. [Materials Department, UCSB, Santa Barbara, California 93106 (United States); Romanov, Alexey E. [Materials Department, UCSB, Santa Barbara, California 93106 (United States); Ioffe Physico-Technical Institute RAS, St. Petersburg 194021 (Russian Federation); ITMO University, St. Petersburg 197101 (Russian Federation); Beltz, Glenn E. [Mechanical Engineering Department, UCSB, Santa Barbara, California 93106 (United States)

    2016-07-21

    We investigate the bow of free standing (0001) oriented hydride vapor phase epitaxy grown GaN substrates and demonstrate that their curvature is consistent with a compressive to tensile stress gradient (bottom to top) present in the substrates. The origin of the stress gradient and the curvature is attributed to the correlated inclination of edge threading dislocation (TD) lines away from the [0001] direction. A model is proposed and a relation is derived for bulk GaN substrate curvature dependence on the inclination angle and the density of TDs. The model is used to analyze the curvature for commercially available GaN substrates as determined by high resolution x-ray diffraction. The results show a close correlation between the experimentally determined parameters and those predicted from theoretical model.

  17. The bowed catheter sign: a risk for pericardial tamponade

    Energy Technology Data Exchange (ETDEWEB)

    Towbin, Richard [Phoenix Children' s Hospital, Department of Radiology, Phoenix, AZ (United States)

    2008-03-15

    The use of a central venous catheter (CVC) has become commonplace in the care of children with a wide variety of medical and surgical problems. Complications resulting from the insertion of these catheters are well recognized and can be life-threatening. When a temporary CVC or other catheter is inserted into the central venous system it is secured to the skin with a combination of sutures and sterile dressing. This fixes the catheter in place and does not allow it to retract, thereby putting pressure on the right atrial wall via the catheter tip if it is too long. The probability of wall penetration is increased if a catheter or device is tapered at the point of contact. The purpose of this case report is to present the bowed catheter sign and to review the anatomy of the cavotricuspid isthmus, a possible predisposing factor to cardiac perforation and tamponade. (orig.)

  18. On the kinematics and thickness of the terrestrial bow shock

    Science.gov (United States)

    Kruparova, Oksana; Krupar, Vratislav; Santolik, Ondrej; Soucek, Jan; Safrankova, Jana; Nemecek, Zdenek; Nemec, Frantisek; Maksimovic, Milan

    2017-04-01

    The bow shock (BS) is formed due to the continuous interaction between the supersonic solar wind and the Earth's magnetosphere ahead of the magnetopause. Thanks to its proximity, BS is a perfect object to study a wide range of phenomena related to collisionless shocks and wave-particle interactions. We have analyzed more than 500 quasi-perpendicular BS crossings between 2001 and 2015 using data retrieved by the magnetometers aboard the four Cluster spacecraft. Applying a simple timing method to four-point measurement, we estimated the BS normal direction and velocity along this direction case by case. Next, we applied the Butterworth filter to numerical derivations of time-intensity profiles to estimate temporal sizes of BS magnetic ramps, and consequently spatial ones using obtained velocities. We have found that BS ramp scales are statistically around 50 km. We discuss relation between the BS ramp scales and both Alfven and magnetosonic Mach numbers.

  19. Violin Pedagogy and the Physics of the Bowed String

    Science.gov (United States)

    McLeod, Alexander Rhodes

    The paper describes the mechanics of violin tone production using non-specialist language, in order to present a scientific understanding of tone production accessible to a broad readership. As well as offering an objective understanding of tone production, this model provides a powerful tool for analyzing the technique of string playing. The interaction between the bow and the string is quite complex. Literature reviewed for this study reveals that scientific investigations have provided important insights into the mechanics of string playing, offering explanations for factors which both contribute to and limit the range of tone colours and dynamics that stringed instruments can produce. Also examined in the literature review are significant works of twentieth century violin pedagogy exploring tone production on the violin, based on the practical experience of generations of teachers and performers. Hermann von Helmholtz described the stick-slip cycle which drives the string in 1863, which replaced earlier ideas about the vibration of violin strings. Later, scientists such as John Schelleng and Lothar Cremer were able to demonstrate how the mechanics of the bow-string interaction can create different tone colours. Recent research by Anders Askenfelt, Knut Guettler, and Erwin Schoonderwaldt have continued to refine earlier research in this area. The writings of Lucien Capet, Leopold Auer, Carl Flesch, Paul Rolland, Kato Havas, Ivan Galamian, and Simon Fischer are examined and analyzed. Each author describes a different approach to tone production on the violin, representing a different understanding of the underlying mechanism. Analyzing these writings within the context of a scientific understanding of tone production makes it possible to compare these approaches more consistently, and to synthesize different concepts drawn from the diverse sources evaluated.

  20. A comparison of 3 methods of face-bow transfer recording: implications for orthognathic surgery.

    Science.gov (United States)

    Gateno, J; Forrest, K K; Camp, B

    2001-06-01

    The purpose of this study was to compare the occlusal plane inclination of models mounted using 3 different systems for face-bow transfer with the actual occlusal plane inclination as measured on a cephalometric radiograph. Twenty-two subjects were enrolled in this study. Three alginate impressions of the maxillary dentition were taken, and 3 stone dental models were produced for each subject. Face-bow recordings were obtained on each subject using the SAM Anatomical Face-bow (Great Lakes Orthodontics Products, Ltd, Tonawanda, NY), the Erickson Surgical Face-bow (Great Lakes Orthodontics Products, Ltd) and a new technique developed by one of the authors (J.G.). For each subject, the dental models were mounted on a SAM articulator using each of the 3 face-bow recordings. Finally, a lateral cephalometric radiograph was obtained for each subject. The occlusal plane inclination was measured on the models and on the cephalometric radiographs. Differences among groups were tested using a 1-way analysis of variance. Bonferroni test was used for post hoc comparison between different pairs of groups. The average occlusal plane inclination using the SAM Anatomical Face-bow was 7.8 degrees +/- 4.2 degrees greater than the actual-a difference that was statistically significant. The mean occlusal plane inclination of the models obtained using the Erickson Surgical Face-bow was 4.4 degrees +/- 2.2 degrees greater than the actual-a difference that was also statistically significant. The mean occlusal plane inclination of the models obtained by the new technique was only 0.9 degrees +/- 1.2 degrees greater than the actual; this difference was not statistically significant. The new mounting technique is more accurate than the conventional SAM Face-bow or the Erickson Face-bow for reproducing the actual occlusal plane inclination. Copyright 2001 American Association of Oral and Maxillofacial Surgeons.

  1. Spatial scales of the magnetic ramp at the Venusian bow shock

    National Research Council Canada - National Science Library

    A. P. Dimmock; S. N. Walker; T. L. Zhang; S. A. Pope

    2011-01-01

    .... The study encompasses around 60 crossings of the Venusian bow shock from 2006 to 2009. The statistical relationship between the shock ramp spatial scales, overshoot and upstream shock parameters are investigated...

  2. DOUBLE BOW SHOCKS AROUND YOUNG, RUNAWAY RED SUPERGIANTS: APPLICATION TO BETELGEUSE

    Energy Technology Data Exchange (ETDEWEB)

    Mackey, Jonathan; Mohamed, Shazrene; Neilson, Hilding R.; Langer, Norbert; Meyer, Dominique M.-A., E-mail: jmackey@astro.uni-bonn.de [Argelander-Institut fuer Astronomie, Auf dem Huegel 71, D-53121 Bonn (Germany)

    2012-05-20

    A significant fraction of massive stars are moving supersonically through the interstellar medium (ISM), either due to disruption of a binary system or ejection from their parent star cluster. The interaction of their wind with the ISM produces a bow shock. In late evolutionary stages these stars may undergo rapid transitions from red to blue and vice versa on the Hertzsprung-Russell diagram, with accompanying rapid changes to their stellar winds and bow shocks. Recent three-dimensional simulations of the bow shock produced by the nearby runaway red supergiant (RSG) Betelgeuse, under the assumption of a constant wind, indicate that the bow shock is very young (<30, 000 years old), hence Betelgeuse may have only recently become an RSG. To test this possibility, we have calculated stellar evolution models for single stars which match the observed properties of Betelgeuse in the RSG phase. The resulting evolving stellar wind is incorporated into two-dimensional hydrodynamic simulations in which we model a runaway blue supergiant (BSG) as it undergoes the transition to an RSG near the end of its life. We find that the collapsing BSG wind bubble induces a bow shock-shaped inner shell around the RSG wind that resembles Betelgeuse's bow shock, and has a similar mass. Surrounding this is the larger-scale retreating bow shock generated by the now defunct BSG wind's interaction with the ISM. We suggest that this outer shell could explain the bar feature located (at least in projection) just in front of Betelgeuse's bow shock.

  3. Asymmetric Outer Bow Length and Cervical Headgear Force System: 3D Analysis Using Finite Element Method.

    Science.gov (United States)

    Geramy, Allahyar; Hassanpour, Mehdi; Emadian Razavi, Elham Sadat

    2015-03-01

    This study sought to assess distal and lateral forces and moments of asymmetric headgears by variable outer bow lengths. Four 3D finite element method (FEM) models of a cervical headgear attached to the maxillary first molars were designed in SolidWorks 2010 software and transferred to ANSYS Workbench ver. 11 software. Models contained the first molars, their periodontal ligament (PDL), cancellous and cortical bones, a mesiodistal slice of the maxillae and the headgear. Models were the same except for the outer bow length in headgears. The headgear was symmetric in model 1. In models 2 to 4, the headgears were asymmetric in length with differences of 5mm, 10mm and 15mm, respectively. A 2.5 N force in horizontal plane was applied and the loading manner of each side of the outer bow was calculated trigonometrically using data from a volunteer. The 15mm difference in outer bow length caused the greatest difference in lateral (=0.21 N) and distal (= 1.008 N) forces and also generated moments (5.044 N.mm). As the difference in outer bow length became greater, asymmetric effects increased. Greater distal force in the longer arm side was associated with greater lateral force towards the shorter arm side and more net yawing moment. A difference range of 1mm to 15 mm of length in cervical headgear can be considered as a safe length of outer bow shortening in clinical use.

  4. Anterior Femoral Bow and Possible Effect on the Stifle Joint: A Comparison between Humans and Dogs.

    Science.gov (United States)

    Ocal, M K; Sabanci, S S; Cobanoglu, M; Enercan, M

    2017-08-01

    The aim of the study was to compare the anterior bow of the femur between dogs and humans in terms of the possible impact on the stifle joint. The femoral radiographs obtained retrospectively were used to determine the angles and positions of the anterior bow in both dogs (n = 135) and humans (n = 57). Descriptive statistics and Pearson's correlation analysis were used for the statistical analyses of the variables. The mean anterior bow angle (ABA) was 18.3 ± 2.02° and 4.88 ± 1.24° in dogs and humans, respectively. The bow position was at the distal shaft in dogs (64.9 ± 2.04%) and almost at the mid-shaft of the bone (46.5 ± 5.52%) in humans. The ABA was related to the bow position in both humans and dogs. Additionally, the angle correlated with age in humans, while it was correlated with weight and breed in dogs. In conclusion, it is suggested that the anterior bow should be used as a landmark on the femoral axis for the biomechanical research of stifle joint, and dog stifle could be used as a suitable model for human knee in experimental studies for clinicians, while making sure that ethical principles are fully respected. © 2017 Blackwell Verlag GmbH.

  5. PENGARUH ANTI-SLAMMING BULBOUS BOW TERHADAP GERAKAN SLAMMING PADA KAPAL PERINTIS 200 DWT

    Directory of Open Access Journals (Sweden)

    Muhammad Iqbal

    2016-02-01

    Full Text Available Analisis seakeeping (kemampuan olah gerak kapal merupakan aspek penting dalam perancangan kapal. Berdasarkan analisis tersebut, dapat diketahui batas operasional dari sebuah kapal. Salah satunya adalah dapat mengetahui kemampuan kapal pada tinggi gelombang signifikan (Hs tertentu. Memodifikasi bentuk haluan kapal dengan membuat dasar dari haluan tersebut lebih rendah dibandingkan dengan dasar lambung kapal nya (dibawah garis baseline kapal dinamakan Anti-Slamming Bow. Pada penelitian ini, anti-slamming bow ditambahkan dengan ­bulbous bow yang dinamakan dengn Anti-Slamming Bulbous Bow (ASB. Panjang (lasb dan tinggi (hasb Anti-Slamming Bulbous Bow divariasikan untuk mendapatkan probabilitas dan intensitas slamming yang paling rendah. Metode untuk menghitung RAO menggunakan Metode Panel. Hasil penelitian menunjukkan bahwa nilai probabilitas pada kapal existing (model awal pada Hs = 4 m dan Tave = 5 s pada kecepatan 14 knot tidak memenuhi standar kriteria Nordforsk ’87 karena memiliki nilai probabilitas slamming sebesar 12,19%. Selain model awal, model 1, model 3 dan model 5 juga tidak memenuhi standar kriteria karena memiliki nilai probabilitas slamming sebesar 5,19%, 5,04% dan 5,10%. Parameter ukuran anti-slamming bulbous bow terbaik terdapat pada model 6 dimana rasio panjang ASB terhadap Lpp kapal sebesar 0,4 dan rasio tinggi ASB terhadap sarat kapal sebesar 0,4. Sedangkan bentuk Bulbous terbaik adalah Bulbous A yaitu bulbous tipe bentuk titik air tergantung. Model ini memiliki nilai  probabilas sebesar 1,95% dan memenuhi kriteria Nordforsk ’87.

  6. Control wafer bow of InGaP on 200 mm Si by strain engineering

    Science.gov (United States)

    Wang, Bing; Bao, Shuyu; Made, Riko I.; Lee, Kwang Hong; Wang, Cong; Eng Kian Lee, Kenneth; Fitzgerald, Eugene A.; Michel, Jurgen

    2017-12-01

    When epitaxially growing III–V compound semiconductors on Si substrates the mismatch of coefficients of thermal expansion (CTEs) between III–V and Si causes stress and wafer bow. The wafer bow is deleterious for some wafer-scale processing especially when the wafer size is large. Strain engineering was applied in the epitaxy of InGaP films on 200 mm silicon wafers having high quality germanium buffers. By applying compressive strain in the InGaP films to compensate the tensile strain induced by CTE mismatch, wafer bow was decreased from about 100 μm to less than 50 μm. X-ray diffraction studies show a clear trend between the decrease of wafer bow and the compensation of CTE mismatch induced tensile strain in the InGaP layers. In addition, the anisotropic strain relaxation in InGaP films resulted in anisotropic wafer bow along two perpendicular (110) directions. Etch pit density and plane-view transmission electron microscopy characterizations indicate that threading dislocation densities did not change significantly due to the lattice-mismatch applied in the InGaP films. This study shows that strain engineering is an effective method to control wafer bow when growing III–V semiconductors on large size Si substrates.

  7. Bow shock models of ultracompact H II regions

    Energy Technology Data Exchange (ETDEWEB)

    Mac Low, M.; Van Buren, D.; Wood, D.O.S.; Churchwell, E. (NASA, Ames Research Center, Moffett Field, CA (USA) Joint Institute for Laboratory Astrophysics, Boulder, CO (USA) JPL, Pasadena, CA (USA) Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (USA) Washburn Observatory, Madison, WI (USA))

    1991-03-01

    This paper presents models of ultracompact H II regions as the bow shocks formed by massive stars, with strong stellar winds, moving supersonically through molecular clouds. The morphologies, sizes and brightnesses of observed objects match the models well. Plausible models are provided for the ultracompact H II regions G12.21 - 0.1, G29.96 - 0.02, G34.26 + 0.15, and G43.89 - 0.78. To do this, the equilibrium shape of the wind-blown shell is calculated, assuming momentum conservation. Then the shell is illuminated with ionizing radiation from the central star, radiative transfer for free-free emission through the shell is performed, and the resulting object is visualized at various angles for comparison with radio continuum maps. The model unifies most of the observed morphologies of ultracompact H II regions, excluding only those objects with spherical shells. Ram pressure confinement greatly lengthens the life of ultracompact H II regions, explaining the large number that exist in the Galaxy despite their low apparent kinematic ages. 32 refs.

  8. Bow shock models of ultracompact H II regions

    Science.gov (United States)

    Mac Low, Mordecai-Mark; Van Buren, Dave; Wood, Douglas O. S.; Churchwell, ED

    1991-01-01

    This paper presents models of ultracompact H II regions as the bow shocks formed by massive stars, with strong stellar winds, moving supersonically through molecular clouds. The morphologies, sizes and brightnesses of observed objects match the models well. Plausible models are provided for the ultracompact H II regions G12.21 - 0.1, G29.96 - 0.02, G34.26 + 0.15, and G43.89 - 0.78. To do this, the equilibrium shape of the wind-blown shell is calculated, assuming momentum conservation. Then the shell is illuminated with ionizing radiation from the central star, radiative transfer for free-free emission through the shell is performed, and the resulting object is visualized at various angles for comparison with radio continuum maps. The model unifies most of the observed morphologies of ultracompact H II regions, excluding only those objects with spherical shells. Ram pressure confinement greatly lengthens the life of ultracompact H II regions, explaining the large number that exist in the Galaxy despite their low apparent kinematic ages.

  9. Dentofacial effects of a modified tandem traction bow appliance.

    Science.gov (United States)

    Atalay, Zeynep; Tortop, Tuba

    2010-12-01

    The aim of this study was to evaluate the dentofacial effects of a modified tandem traction bow appliance (modified TTBA) in skeletal Class III subjects, and the effect of age on treatment response. The material consisted of the pre-treatment/pre-observation and post-treatment/post-observation lateral cephalograms and hand-wrist films of 45 children with skeletal and dental Class III malocclusions. Thirty patients were treated with a modified TTBA. Two treatment groups of 15 patients each were formed: an early (nine girls, six boys; mean skeletal age: 8.18 ± 0.50 years) and a late treatment (5 girls, 10 boys; mean skeletal age: 11.75 ± 1.00 years) group. The remaining 15 children (5 girls, 10 boys; mean skeletal age: 7.90 ± 0.62 years) were observed without treatment for 8 months and served as a control for the early treatment group. Wilcoxon and Mann-Whitney U-tests were used for statistical analysis. Significant forward maxillary movement was determined in both treatment groups (P skeletal correction of the Class III malocclusion was achieved.

  10. Comparison of accelerated ion populations observed upstream of the bow shocks at Venus and Mars

    Directory of Open Access Journals (Sweden)

    M. Yamauchi

    2011-03-01

    Full Text Available Foreshock ions are compared between Venus and Mars at energies of 0.6~20 keV using the same ion instrument, the Ion Mass Analyser, on board both Venus Express and Mars Express. Venus Express often observes accelerated protons (2~6 times the solar wind energy that travel away from the Venus bow shock when the spacecraft location is magnetically connected to the bow shock. The observed ions have a large field-aligned velocity compared to the perpendicular velocity in the solar wind frame, and are similar to the field-aligned beams and intermediate gyrating component of the foreshock ions in the terrestrial upstream region. Mars Express does not observe similar foreshock ions as does Venus Express, indicating that the Martian foreshock does not possess the intermediate gyrating component in the upstream region on the dayside of the planet. Instead, two types of gyrating protons in the solar wind frame are observed very close to the Martian quasi-perpendicular bow shock within a proton gyroradius distance. The first type is observed only within the region which is about 400 km from the bow shock and flows tailward nearly along the bow shock with a similar velocity as the solar wind. The second type is observed up to about 700 km from the bow shock and has a bundled structure in the energy domain. A traversal on 12 July 2005, in which the energy-bunching came from bundling in the magnetic field direction, is further examined. The observed velocities of the latter population are consistent with multiple specular reflections of the solar wind at the bow shock, and the ions after the second reflection have a field-aligned velocity larger than that of the de Hoffman-Teller velocity frame, i.e., their guiding center has moved toward interplanetary space out from the bow shock. To account for the observed peculiarity of the Martian upstream region, finite gyroradius effects of the solar wind protons compared to the radius of the bow shock curvature and

  11. Exploiting biomechanical degrees of freedom for fast and accurate changes in movement direction: coordination underlying quick bow reversals during continuous cello bowing

    Directory of Open Access Journals (Sweden)

    Julius eVerrel

    2013-04-01

    Full Text Available Theoretical and empirical evidence suggests that accurate and efficient motor performance may be achieved by task-specific exploitation of biomechanical degrees of freedom. We investigate coordination of the right arm in a task requiring a sudden yet precisely controlled reversal of movement direction: bow reversals during continuous (legato tone production on a stringed instrument. Ten advanced or professional cello players (at least ten years of practice and ten age-matched novice players took part in the study. Kinematic data from the bow and the right arm were analyzed in terms of velocity and acceleration profiles, as well as temporal coordination along the arm. As expected, experts’ bow velocity and acceleration profiles differed markedly from those of novice participants, with higher peak accelerations and quicker direction changes. Importantly, experts achieved the change in movement direction with a single acceleration peak while novices tended to use multiple smaller acceleration peaks. Experts moreover showed a proximal-distal gradient in timing and amplitudes of acceleration peaks, with earlier and lower-amplitude reversals at more proximal joints. We suggest that this coordination pattern allows generating high accelerations at the end effector while reducing the required joint torques at the proximal joints. This may underlie experts’ ability to produce fast bow reversals efficiently and with high spatiotemporal accuracy. The findings are discussed in terms of motor control theory as well as potential implications for musicians’ performance and health.

  12. Congenital posteromedial bowing of the tibia: a retrospective analysis of growth abnormalities in the leg.

    Science.gov (United States)

    Shah, Hitesh H; Doddabasappa, Siddesh N; Joseph, Benjamin

    2009-05-01

    We studied case records and radiographs of 20 children with congenital posteromedial bowing of the tibia (CPMBT) retrospectively to determine the pattern of correction of the bowing, the associated growth abnormalities of the tibia and fibula, and the role of surgical intervention in CPMBT. The magnitude of diaphyseal bowing in two planes and the physeal inclination were measured. Abnormalities of ossification of the distal tibial epiphysis and inclination of the distal articular surface if present were noted and shortening of the tibia was recorded. The rate of resolution of deformity was noted from sequential radiographs and expressed as percentage reduction per month of follow-up. At initial presentation the magnitude of deformity varied; the most severe posterior diaphyseal bow was 70 degrees whereas the most severe medial diaphyseal bow was 64 degrees. Two distinct mechanisms seem to be responsible for resolution of the deformity in CPMBT; one involves physeal realignment and the other involves diaphyseal remodeling. In the first year of life, rapid resolution of angulation was noted; the rate of resolution reduced significantly thereafter. In a proportion of children with CPMBT residual deformity may persist till over 4 years of age. Physeal realignment occurred at a faster rate than diaphyseal remodeling. The degree of shortening was related to the severity of bowing and shortening as great as 40% was noted in a patient. Wedging of the distal tibial epiphysis and fibular hypoplasia with valgus inclination of the distal tibial articular surface occur in some children with CPMBT. Eccentric ossification of the distal tibial epiphysis in early childhood may be a predictor of wedging of the distal tibial epiphysis later on. We recommend all the children with CPMBT to be followed up periodically till skeletal maturity, to identify cases with residual bowing, ankle deformity, muscle weakness, and limb length inequality as active surgical intervention may be needed

  13. Polarized bow shocks reveal features of the winds and environments of massive stars

    Science.gov (United States)

    Shrestha, Manisha

    2018-01-01

    Massive stars strongly affect their surroundings through their energetic stellar winds and deaths as supernovae. The bow shock structures created by fast-moving massive stars contain important information about the winds and ultimate fates of these stars as well as their local interstellar medium (ISM). Since bow shocks are aspherical, the light scattered in the dense shock material becomes polarized. Analyzing this polarization reveals details of the bow shock geometry as well as the composition, velocity, density, and albedo of the scattering material. With these quantities, we can constrain the properties of the stellar wind and thus the evolutionary state of the star, as well as the dust composition of the local ISM.In my dissertation research, I use a Monte Carlo radiative transfer code that I optimized to simulate the polarization signatures produced by both resolved and unresolved stellar wind bow shocks (SWBS) illuminated by a central star and by shock emission. I derive bow shock shapes and densities from published analytical calculations and smooth particle hydrodynamic (SPH) models. In the case of the analytical SWBS and electron scattering, I find that higher optical depths produce higher polarization and position angle rotations at specific viewing angles compared to theoretical predictions for low optical depths. This is due to the geometrical properties of the bow shock combined with multiple scattering effects. For dust scattering, the polarization signature is strongly affected by wavelength, dust grain properties, and viewing angle. The behavior of the polarization as a function of wavelength in these cases can distinguish among different dust models for the local ISM. In the case of SPH density structures, I investigate how the polarization changes as a function of the evolutionary phase of the SWBS. My dissertation compares these simulations with polarization data from Betelgeuse and other massive stars with bow shocks. I discuss the

  14. Ion Events Observed by Wind far Upstream From the Bow Shock and by Geotail / Imp-8 Near the Bow Shock and Within the Plasma Sheet

    Science.gov (United States)

    Anagnostopoulos, G.; Efthymiadis, D.; Sarris, E. T.; Krimigis, S. M.

    2002-12-01

    Mason et al. (1996) reported characteristics of short duration energetic (>~30 keV/neucleon) heavy ion enhancements observed by the WIND spacecraft at large distances upstream from the bow shock during two periods of high speed streams (Jan. 20, 1995 - Feb. 19, 1995) and Desai et al (2000) extended their study and presented results from a statistical analysis of upstream events rich in CNO species as observed by the WIND spacecraft between 1994 day 325 to 1999 day 92. Desai et al. suggested that some ion characteristics (as for instance, the fact that the majority of the events were observed in the dawn-noon sector, the solar-wind-like ion composition and the heavy ion dominance of the total energy ion spectrum above ~0.5 MeV) appear to pose severe problems for the leakage model, while other characteristics appear to pose serious challenges for the Fermi acceleration model. In this paper we compare the statistical results of Desai et al. with the results from previous statistical and case studies and we show that the Wind observations are in general consistent with the leakage model. Furthermore, we examine simultaneous multispacecraft observations during time periods of some typical events presented by the authors (Mason et al., 1996; Desai et al., 2000) and we compare them with predictions from the leakage and bow shock acceleration models. In particular: (a) we present observations by WIND far upstream from the bow shock and by Geotail and IMP-8 within the magnetosphere and we infer that particle acceleration within the plasma sheet and subsequent leakage to the upstream region are responsible for the generation of these upstream ion events, and (b) we compare the upstream WIND observations with observations obtained by Geotail and IMP-8 near the bow shock, and we infer that the near bow shock observations do not fit with major predictions of Fermi acceleration models.

  15. Investigating the Function of Play Bows in Dog and Wolf Puppies (Canis lupus familiaris, Canis lupus occidentalis).

    Science.gov (United States)

    Byosiere, Sarah-Elizabeth; Espinosa, Julia; Marshall-Pescini, Sarah; Smuts, Barbara; Range, Friederike

    2016-01-01

    Animals utilize behavioral signals across a range of different contexts in order to communicate with others and produce probable behavioral outcomes. During play animals frequently adopt action patterns used in other contexts. Researchers have therefore hypothesized that play signals have evolved to clarify communicative intent. One highly stereotyped play signal is the canid play bow, but its function remains contested. In order to clarify how canid puppies use play bows, we used data on play bows in immature wolves (ages 2.7-7.8 months) and dogs (ages 2 to 5 months) to test hypotheses evaluated in a previous study of adult dogs. We found that young dogs used play bows similarly to adult dogs; play bows most often occurred after a brief pause in play followed by complementary highly active play states. However, while the relative number of play bows and total observation time was similar between dog and wolf puppies, wolves did not follow this behavioral pattern, as play bows were unsuccessful in eliciting further play activity by the partner. While some similarities for the function of play bows in dog and wolf puppies were documented, it appears that play bows may function differently in wolf puppies in regards to re-initiating play.

  16. Investigating the Function of Play Bows in Dog and Wolf Puppies (Canis lupus familiaris, Canis lupus occidentalis.

    Directory of Open Access Journals (Sweden)

    Sarah-Elizabeth Byosiere

    Full Text Available Animals utilize behavioral signals across a range of different contexts in order to communicate with others and produce probable behavioral outcomes. During play animals frequently adopt action patterns used in other contexts. Researchers have therefore hypothesized that play signals have evolved to clarify communicative intent. One highly stereotyped play signal is the canid play bow, but its function remains contested. In order to clarify how canid puppies use play bows, we used data on play bows in immature wolves (ages 2.7-7.8 months and dogs (ages 2 to 5 months to test hypotheses evaluated in a previous study of adult dogs. We found that young dogs used play bows similarly to adult dogs; play bows most often occurred after a brief pause in play followed by complementary highly active play states. However, while the relative number of play bows and total observation time was similar between dog and wolf puppies, wolves did not follow this behavioral pattern, as play bows were unsuccessful in eliciting further play activity by the partner. While some similarities for the function of play bows in dog and wolf puppies were documented, it appears that play bows may function differently in wolf puppies in regards to re-initiating play.

  17. Finite element method (FEM) analysis of the force systems produced by asymmetric inner headgear bows.

    Science.gov (United States)

    Geramy, Allahyar; Kizilova, Natalya; Terekhov, Leonid

    2011-11-01

    Extra-oral traction appliances were introduced more than a century ago and continue to be used to produce orthopaedic and/or dental changes in the maxilla. While force systems produced by asymmetric outer bows have been studied extensively, the force systems produced by asymmetric inner bows have been overlooked. To analyse the forces acting on the maxillary first molars: when the size of one bayonet bend is increased; when the point of application of the distalising force on the inner bow is moved to one side; when one molar is displaced palatally. Four FEM models of cervical headgear attached to maxillary first molars were designed in SolidWorks 2010 and transferred to an ANSYS Workbench Ver. 12.1. Model 1, each molar was 23 mm from the midpalatal line and the inner bow was symmetrical; Model 2, the left molar was displaced 4 mm towards the midpalatal line and the inner bow was symmetrical; Model 3, the molars were equidistant (23 mm) from the midpalatal line, but the left molar was engaged by a 2 mm larger bayonet bend; Model 4, the molars were equidistant (23 mm) from the midpalatal line but the join between the inner and outer bows was displaced 2 mm towards the left molar. In all FEM models, a 2N force was applied to the inner bow at the join between inner and outer bows and the energy transmitted to the teeth and the von Mises stresses on the molar PDLs were assessed. There were marked differences in the strain energy on the teeth and the von Mises stresses on their PDLs. A 14 to 20 per cent increase in energy and force was produced on the tooth closer to the symmetric plane of the headgear. In addition, the increase in energy produced a 30 to 62 per cent increase in the von Mises stresses within the PDLs. Small asymmetries in molar position, the size of a bayonet bend and the point of application of a force on an inner bow resulted in asymmetrical forces on the molars. These forces were higher on the molar closer to the symmetric plane of the headgear.

  18. Unilateral Outer Bow Expanded Cervical Headgear Force System: 3D Analysis Using Finite Element Method.

    Science.gov (United States)

    Geramy, Allahyar; Mortezai, Omid; Esmaily, Masomeh; Darvishpour, Hojat

    2015-04-01

    Headgears are among the effective orthodontic appliances to achieve treatment goals. Unilateral molar distal movement is sometimes needed during an orthodontic treatment, which can be achieved by an asymmetric headgear. Different unilateral headgears have been introduced. The main goal of this study was to analyze the force system of unilateral expanded outer bow asymmetric headgears by the finite element method (FEM). Six 3D finite element models of a mesiodistal slice of the maxilla containing upper first molars, their periodontal ligaments (PDLs), cancellous bone, cortical bone, and a cervical headgear with expanded outer bow attached to maxillary first molars were designed in SolidWorks 2010 and meshed in ANSYS Workbench ver. 12.1. The models were the same except for the degree of outer bow expansion. The outer bow ends were loaded with 2 N force. The distal driving force and the net moment were evaluated. A decrease in the distalizing force in the normal side molar from 1.69 N to 1.37 N was shown by increasing the degree of unilateral expansion. At the same time, the force increased from 2.19 N to 2.49 N in the expanded side molar. A net moment increasing from 2.26 N.mm to 4.64 N.mm was also shown. Unilateral outer bow expansion can produce different distalizing forces in molars, which increase by increasing the expansion.

  19. Unilateral Outer Bow Expanded Cervical Headgear Force System: 3D Analysis Using Finite Element Method

    Directory of Open Access Journals (Sweden)

    Allahyar Geramy

    2015-10-01

    Full Text Available Objectives: Headgears are among the effective orthodontic appliances to achieve treatment goals. Unilateral molar distal movement is sometimes needed during an orthodontic treat- ment, which can be achieved by an asymmetric headgear. Different unilateral headgears have been introduced. The main goal of this study was to analyze the force system of uni- lateral expanded outer bow asymmetric headgears by the finite element method (FEM.Materials and Methods: Six 3D finite element models of a mesiodistal slice of the maxilla containing upper first molars, their periodontal ligaments (PDLs, cancellous bone, cortical bone, and a cervical headgear with expanded outer bow attached to maxillary first molars were designed in SolidWorks 2010 and meshed in ANSYS Workbench ver. 12.1. The mod- els were the same except for the degree of outer bow expansion. The outer bow ends were loaded with 2-Newton force. The distal driving force and the net moment were evaluated.Results: A decrease in the distalizing force in the normal side molar from 1.69 N to 1.37 N was shown by increasing the degree of unilateral expansion. At the same time, the force increased from 2.19 N to 2.49 N in the expanded side molar. A net moment increasing from 2.26 N.mm to 4.64 N.mm was also shown.Conclusion: Unilateral outer bow expansion can produce different distalizing forces in mo- lars, which increase by increasing the expansion.

  20. BOWS (bioinformatics open web services) to centralize bioinformatics tools in web services.

    Science.gov (United States)

    Velloso, Henrique; Vialle, Ricardo A; Ortega, J Miguel

    2015-06-02

    Bioinformaticians face a range of difficulties to get locally-installed tools running and producing results; they would greatly benefit from a system that could centralize most of the tools, using an easy interface for input and output. Web services, due to their universal nature and widely known interface, constitute a very good option to achieve this goal. Bioinformatics open web services (BOWS) is a system based on generic web services produced to allow programmatic access to applications running on high-performance computing (HPC) clusters. BOWS intermediates the access to registered tools by providing front-end and back-end web services. Programmers can install applications in HPC clusters in any programming language and use the back-end service to check for new jobs and their parameters, and then to send the results to BOWS. Programs running in simple computers consume the BOWS front-end service to submit new processes and read results. BOWS compiles Java clients, which encapsulate the front-end web service requisitions, and automatically creates a web page that disposes the registered applications and clients. Bioinformatics open web services registered applications can be accessed from virtually any programming language through web services, or using standard java clients. The back-end can run in HPC clusters, allowing bioinformaticians to remotely run high-processing demand applications directly from their machines.

  1. BOW SHOCK FRAGMENTATION DRIVEN BY A THERMAL INSTABILITY IN LABORATORY ASTROPHYSICS EXPERIMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki-Vidal, F.; Lebedev, S. V.; Pickworth, L. A.; Swadling, G. F.; Skidmore, J.; Hall, G. N.; Bennett, M.; Bland, S. N.; Burdiak, G.; De Grouchy, P.; Music, J.; Suttle, L. [Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2BW (United Kingdom); Ciardi, A. [Sorbonne Universités, UPMC Univ. Paris 6, UMR 8112, LERMA, F-75005, Paris (France); Rodriguez, R.; Gil, J. M.; Espinosa, G. [Departamento de Fisica de la Universidad de Las Palmas de Gran Canaria, E-35017 Las Palmas de Gran Canaria (Spain); Hartigan, P. [Department of Physics and Astronomy, Rice University, 6100 S. Main, Houston, TX 77521-1892 (United States); Hansen, E.; Frank, A., E-mail: f.suzuki@imperial.ac.uk [Department of Physics and Astronomy, University of Rochester, Rochester, NY 14627 (United States)

    2015-12-20

    The role of radiative cooling during the evolution of a bow shock was studied in laboratory-astrophysics experiments that are scalable to bow shocks present in jets from young stellar objects. The laboratory bow shock is formed during the collision of two counterstreaming, supersonic plasma jets produced by an opposing pair of radial foil Z-pinches driven by the current pulse from the MAGPIE pulsed-power generator. The jets have different flow velocities in the laboratory frame, and the experiments are driven over many times the characteristic cooling timescale. The initially smooth bow shock rapidly develops small-scale nonuniformities over temporal and spatial scales that are consistent with a thermal instability triggered by strong radiative cooling in the shock. The growth of these perturbations eventually results in a global fragmentation of the bow shock front. The formation of a thermal instability is supported by analysis of the plasma cooling function calculated for the experimental conditions with the radiative packages ABAKO/RAPCAL.

  2. Blade bowing effects on radial equilibrium of inlet flow in axial compressor cascades

    Directory of Open Access Journals (Sweden)

    Han XU

    2017-10-01

    Full Text Available The circumferentially averaged equation of the inlet flow radial equilibrium in axial compressor was deduced. It indicates that the blade inlet radial pressure gradient is closely related to the radial component of the circumferential fluctuation (CF source item. Several simplified cascades with/without aerodynamic loading were numerically studied to investigate the effects of blade bowing on the inlet flow radial equilibrium. A data reduction program was conducted to obtain the CF source from three-dimensional (3D simulation results. Flow parameters at the passage inlet were focused on and each term in the radial equilibrium equation was discussed quantitatively. Results indicate that the inviscid blade force is the inducement of the inlet CF due to geometrical asymmetry. Blade bowing induces variation of the inlet CF, thus changes the radial pressure gradient and leads to flow migration before leading edge (LE in the cascades. Positive bowing drives the inlet flow to migrate from end walls to mid-span and negative bowing turns it to the reverse direction to build a new equilibrium. In addition, comparative studies indicate that the inlet Mach number and blade loading can efficiently impact the effectiveness of blade bowing on radial equilibrium in compressor design.

  3. Bow shock nebulae of hot massive stars in a magnetized medium

    Science.gov (United States)

    Meyer, D. M.-A.; Mignone, A.; Kuiper, R.; Raga, A. C.; Kley, W.

    2017-01-01

    A significant fraction of OB-type, main-sequence massive stars are classified as runaway and move supersonically through the interstellar medium (ISM). Their strong stellar winds interact with their surroundings, where the typical strength of the local ISM magnetic field is about 3.5-7 μG, which can result in the formation of bow shock nebulae. We investigate the effects of such magnetic fields, aligned with the motion of the flow, on the formation and emission properties of these circumstellar structures. Our axisymmetric, magneto-hydrodynamical simulations with optically thin radiative cooling, heating and anisotropic thermal conduction show that the presence of the background ISM magnetic field affects the projected optical emission of our bow shocks at Hα and [O III] λ 5007 which become fainter by about 1-2 orders of magnitude, respectively. Radiative transfer calculations against dust opacity indicate that the magnetic field slightly diminishes their projected infrared emission and that our bow shocks emit brightly at 60 μm. This may explain why the bow shocks generated by ionizing runaway massive stars are often difficult to identify. Finally, we discuss our results in the context of the bow shock of ζ Ophiuchi and we support the interpretation of its imperfect morphology as an evidence of the presence of an ISM magnetic field not aligned with the motion of its driving star.

  4. Improved bow shock models for Herbig-Haro objects - Application to HH 2A-prime

    Science.gov (United States)

    Raymond, John C.; Hartmann, Lee; Hartigan, Patrick

    1988-01-01

    An improved version of the bow shock theory previously applied to Herbig-Haro objects is presented. The modifications provide a more accurate calculation of the ionization state of material entering the bow shock. The revised preionization does not drastically affect the emission-line predictions for a 200 km/s bow shock model, though the effects will be more severe for slower shock velocities. The line profiles of the new models resemble the observed profiles somewhat more closely, and the relative emission-line intensities typically differ by 30 percent from those predicted by the older models. The models agree well with new IUE spectra and existing optical data for HH 2A-prime.

  5. Research on bulbous bow optimization based on the improved PSO algorithm

    Science.gov (United States)

    Zhang, Sheng-long; Zhang, Bao-ji; Tezdogan, Tahsin; Xu, Le-ping; Lai, Yu-yang

    2017-08-01

    In order to reduce the total resistance of a hull, an optimization framework for the bulbous bow optimization was presented. The total resistance in calm water was selected as the objective function, and the overset mesh technique was used for mesh generation. RANS method was used to calculate the total resistance of the hull. In order to improve the efficiency and smoothness of the geometric reconstruction, the arbitrary shape deformation (ASD) technique was introduced to change the shape of the bulbous bow. To improve the global search ability of the particle swarm optimization (PSO) algorithm, an improved particle swarm optimization (IPSO) algorithm was proposed to set up the optimization model. After a series of optimization analyses, the optimal hull form was found. It can be concluded that the simulation based design framework built in this paper is a promising method for bulbous bow optimization.

  6. Electron bow-wave injection of electrons in laser-driven bubble acceleration.

    Science.gov (United States)

    Ma, Y Y; Kawata, S; Yu, T P; Gu, Y Q; Sheng, Z M; Yu, M Y; Zhuo, H B; Liu, H J; Yin, Y; Takahashi, K; Xie, X Y; Liu, J X; Tian, C L; Shao, F Q

    2012-04-01

    An electron injection regime in laser wake-field acceleration, namely electron bow-wave injection, is investigated by two- and three-dimensional particle-in-cell simulation as well as analytical model. In this regime electrons in the intense electron bow wave behind the first bubble catch up with the bubble tail and are trapped by the bubble finally, resulting in considerable enhancement of the total trapped electron number. For example, with the increase of the laser intensity from 2 × 10(19) to 1 × 10(20) W/cm(2), the electron trapping changes from normal self-injection to bow-wave injection and the trapped electron number is enhanced by two orders of magnitude. An analytical model is proposed to explain the numerical observation.

  7. Prenatal diagnosis of metatropic dysplasia: beware of the pseudo-bowing sign

    Energy Technology Data Exchange (ETDEWEB)

    Garel, Catherine [Trousseau Hospital, University Hospitals of the East of Paris, Department of Radiology, Paris (France); Hopital d' Enfants Armand-Trousseau, Department of Radiology, Paris (France); Dhouib, Amira; Sileo, Chiara; Ducou le Pointe, Hubert [Trousseau Hospital, University Hospitals of the East of Paris, Department of Radiology, Paris (France); Cormier-Daire, Valerie [Paris Descartes University, Sorbonne Paris Cite, Necker-Enfants-Malades Hospital, Department of Genetics, Paris (France)

    2014-03-15

    Metatropic dysplasia is a very rare form of osteochondrodysplasia with only one case of prenatal diagnosis described in the literature. It is characterized by marked shortening of the long bones with severe platyspondyly and dumbbell-shape metaphyses. We report a case of metatropic dysplasia that was diagnosed prenatally and describe the findings on US and CT. The pregnancy was terminated and the post-mortem radiographs are shown. The woman had been referred for short and bowed long bones. Severe metaphyseal enlargement was a misleading finding because it had been misinterpreted as limb bowing. Thus when abnormal curvature of the long bones is observed at prenatal US, attention should be drawn not only to the diaphyses but also to the metaphyses because severe metaphyseal enlargement might be responsible for pseudo-bowing. (orig.)

  8. Asymmetric Outer Bow Length and Cervical Headgear Force System: 3D Analysis Using Finite Element Method

    Directory of Open Access Journals (Sweden)

    Allahyar Geramy

    2015-10-01

    Full Text Available Objectives: This study sought to assess distal and lateral forces and moments of asymmetric headgears by variable outer bow lengths.Materials and Methods: Four 3D finite element method (FEM models of a cer- vical headgear attached to the maxillary first molars were designed in SolidWorks2010 software and transferred to ANSYS Workbench ver. 11 software. Modelscontained the first molars, their periodontal ligament (PDL, cancellous and cor- tical bones, a mesiodistal slice of the maxillae and the headgear. Models were the same except for the outer bow length in headgears. The headgear was symmetric in model 1. In models 2 to 4, the headgears were asymmetric in length with dif- ferences of 5mm, 10mm and 15mm, respectively. A 2.5 N force in horizontal plane was applied and the loading manner of each side of the outer bow was cal- culated trigonometrically using data from a volunteer.Results: The 15mm difference in outer bow length caused the greatest difference in lateral (=0.21 N and distal (= 1.008 N forces and also generated moments (5.044 N.mm.Conclusion: As the difference in outer bow length became greater, asymmetric effects increased. Greater distal force in the longer arm side was associated with greater lateral force towards the shorter arm side and more net yawing moment. Clinical Relevance:A difference range of 1mm to 15 mm of length in cervical headgear can be consi-dered as a safe length of outer bow shortening in clinical use.

  9. Acute traumatic stroke: a case of bow hunter's stroke in a child.

    Science.gov (United States)

    Duval, E L; Van Coster, R; Verstraeten, K

    1998-06-01

    Acute traumatic stroke of the cerebellum is rarely seen in children. In adults, chiropractical manipulation, yoga exercises, bow hunting and cervical trauma have all been associated with vertebrobasillar damage and subsequent stroke due to cerebellar infarction. We present a case of bow hunter's stroke in a child. An 11-year-old boy developed deep coma one day after minor occipital head injury due to an infarct in the left cerebellum and ipsilateral medulla oblongata. Magnetic resonance angiography (MRA) showed hypoperfusion of the left vertebral artery and occlusion of the posterior and anterior inferior cerebellar arteries (PICA and AICA respectively).

  10. Anomalous band bowing in pulsed laser deposited MgxZn1-xO films

    Science.gov (United States)

    Agrawal, Arpana; Dar, Tanveer Ahmad; Phase, D. M.; Sen, Pratima

    2013-12-01

    Random variation of band bowing in pulsed laser deposited Mg doped (x=0.090, 0.147, 0.211, 0.268) ZnO thin films was observed. The X-ray diffraction and ultraviolet-visible spectroscopy data reveal lattice relaxation and increase in band gap as well as disorderness in the samples. The X-ray photoelectron spectroscopy data confirm the presence of magnesium and oxygen interstitials (Mgi and Oi) as well as oxygen vacancies (VO). The randomness of band bowing is attributed to the presence of these defects.

  11. The distant bow shock and magnetotail of Venus - Magnetic field and plasma wave observations

    Science.gov (United States)

    Russell, C. T.; Luhmann, J. G.; Elphic, R. C.; Scarf, F. L.

    1981-01-01

    An examination of the magnetic field and plasma wave data obtained by the Pioneer Venus orbiter in the wake region behind Venus discloses a well developed bow shock whose location is similar to that observed on previous missions in contrast to the dayside bow shock. Venus also has a well developed magnetotail in which the field strenght is enhanced over magnetosheath values and in which the magnetic field is aligned approximately with the solar wind direction. The boundary between magnetosheath and magnetotail is also marked by a change in the plasma wave spectrum.

  12. 76 FR 78234 - Medicine Bow-Routt National Forests and Thunder Basin National Grassland, Campbell County, WY...

    Science.gov (United States)

    2011-12-16

    ... Forest Service Medicine Bow-Routt National Forests and Thunder Basin National Grassland, Campbell County...: Send written comments to Richard A. Cooksey, Deputy Forest Supervisor, Medicine Bow-Routt National... Information Relay Service (FIRS) at 1-800-877-8339 between 8 a.m. and 8 p.m., Eastern Time, Monday through...

  13. Non-stationarity of the quasi-perpendicular bow shock: comparison between Cluster observations and simulations

    Czech Academy of Sciences Publication Activity Database

    Comisel, H.; Scholer, M.; Souček, Jan; Matsukiyo, S.

    2011-01-01

    Roč. 29, č. 2 (2011), s. 263-274 ISSN 0992-7689 Institutional research plan: CEZ:AV0Z30420517 Keywords : bow shock * Cluster * plasma waves * shock waves Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.842, year: 2011 http://www.ann-geophys.net/29/263/2011/angeo-29-263-2011.pdf

  14. Bow shocks as tracers of the environment and stellar outflows near the supermassive black hole.

    Science.gov (United States)

    Stofanova, L.; Zajaček, M.; Karas, V.

    2017-10-01

    Bow shocks develop near stars in the supersonic motion with respect to the surrounding interstellar environment. In particular, extended shocks emerge due to the interaction of stars with strong winds. We discuss the expected shape and orientation of bow shocks in the context of fast moving stars near a supermassive black hole (SMBH) embedded within Bondi-type accretion flow (Zajaček et al. 2016, MNRAS; Štofanová 2016, BSc. Thesis). We present models which take into account different velocities of the probe star and also consider various scenarios for the ambient medium near the vicinity of the black hole such as an inflow/outflow of the material towards/outwards SMBH or a model which considers inflow and outflow at the same time. Under suitable circumstances, a bow shock structure can be detected in infrared domain and their properties can trace the environment of the Galactic center. On the other hand, if density of the ambient medium is determined from mm/radio observations, bow shocks can be used to constrain mass-loss rates of massive OB/WR stars. X-rays can supplement the spectral evidence, though, the structures are below the angular resolution of the current instruments even in the most favourable case of the Milky Way's SMBH (Sgr A*).

  15. A benchmark study of procedures for analysis of axial crushing of bulbous bows

    DEFF Research Database (Denmark)

    Yamada, Yasuhira; Pedersen, Preben Terndrup

    2008-01-01

    Simplified methods to estimate mean axial crushing forces of plated structures are reviewed and applied to a series of experimental results for axial crushing of large-scale bulbous bow models. Methods based on intersection unit elements such as L-, T- and X-type elements as well as methods based...

  16. Modelling the ballistics and thermodynamics of bow spray droplets for marine icing

    NARCIS (Netherlands)

    Hoes, C.M.; Aalbers, AB; Hoving, J.S.

    2016-01-01

    In preparation to the SALTO JIP (Safe Arctic Logistics, Transport & Operations) work was done towards developing an improved model for icing due to sea spray at the bow of a ship. The so-called SHIPICE model may be used in a probabilistic risk-based approach and consists of two main segments: 1.

  17. Fuzzy Bayesian Network-Bow-Tie Analysis of Gas Leakage during Biomass Gasification

    Science.gov (United States)

    Yan, Fang; Xu, Kaili; Yao, Xiwen; Li, Yang

    2016-01-01

    Biomass gasification technology has been rapidly developed recently. But fire and poisoning accidents caused by gas leakage restrict the development and promotion of biomass gasification. Therefore, probabilistic safety assessment (PSA) is necessary for biomass gasification system. Subsequently, Bayesian network-bow-tie (BN-bow-tie) analysis was proposed by mapping bow-tie analysis into Bayesian network (BN). Causes of gas leakage and the accidents triggered by gas leakage can be obtained by bow-tie analysis, and BN was used to confirm the critical nodes of accidents by introducing corresponding three importance measures. Meanwhile, certain occurrence probability of failure was needed in PSA. In view of the insufficient failure data of biomass gasification, the occurrence probability of failure which cannot be obtained from standard reliability data sources was confirmed by fuzzy methods based on expert judgment. An improved approach considered expert weighting to aggregate fuzzy numbers included triangular and trapezoidal numbers was proposed, and the occurrence probability of failure was obtained. Finally, safety measures were indicated based on the obtained critical nodes. The theoretical occurrence probabilities in one year of gas leakage and the accidents caused by it were reduced to 1/10.3 of the original values by these safety measures. PMID:27463975

  18. Fuzzy Bayesian Network-Bow-Tie Analysis of Gas Leakage during Biomass Gasification.

    Directory of Open Access Journals (Sweden)

    Fang Yan

    Full Text Available Biomass gasification technology has been rapidly developed recently. But fire and poisoning accidents caused by gas leakage restrict the development and promotion of biomass gasification. Therefore, probabilistic safety assessment (PSA is necessary for biomass gasification system. Subsequently, Bayesian network-bow-tie (BN-bow-tie analysis was proposed by mapping bow-tie analysis into Bayesian network (BN. Causes of gas leakage and the accidents triggered by gas leakage can be obtained by bow-tie analysis, and BN was used to confirm the critical nodes of accidents by introducing corresponding three importance measures. Meanwhile, certain occurrence probability of failure was needed in PSA. In view of the insufficient failure data of biomass gasification, the occurrence probability of failure which cannot be obtained from standard reliability data sources was confirmed by fuzzy methods based on expert judgment. An improved approach considered expert weighting to aggregate fuzzy numbers included triangular and trapezoidal numbers was proposed, and the occurrence probability of failure was obtained. Finally, safety measures were indicated based on the obtained critical nodes. The theoretical occurrence probabilities in one year of gas leakage and the accidents caused by it were reduced to 1/10.3 of the original values by these safety measures.

  19. Fuzzy Bayesian Network-Bow-Tie Analysis of Gas Leakage during Biomass Gasification.

    Science.gov (United States)

    Yan, Fang; Xu, Kaili; Yao, Xiwen; Li, Yang

    2016-01-01

    Biomass gasification technology has been rapidly developed recently. But fire and poisoning accidents caused by gas leakage restrict the development and promotion of biomass gasification. Therefore, probabilistic safety assessment (PSA) is necessary for biomass gasification system. Subsequently, Bayesian network-bow-tie (BN-bow-tie) analysis was proposed by mapping bow-tie analysis into Bayesian network (BN). Causes of gas leakage and the accidents triggered by gas leakage can be obtained by bow-tie analysis, and BN was used to confirm the critical nodes of accidents by introducing corresponding three importance measures. Meanwhile, certain occurrence probability of failure was needed in PSA. In view of the insufficient failure data of biomass gasification, the occurrence probability of failure which cannot be obtained from standard reliability data sources was confirmed by fuzzy methods based on expert judgment. An improved approach considered expert weighting to aggregate fuzzy numbers included triangular and trapezoidal numbers was proposed, and the occurrence probability of failure was obtained. Finally, safety measures were indicated based on the obtained critical nodes. The theoretical occurrence probabilities in one year of gas leakage and the accidents caused by it were reduced to 1/10.3 of the original values by these safety measures.

  20. Large Scale Earth's Bow Shock with Northern IMF as Simulated by ...

    Indian Academy of Sciences (India)

    magnetopause—bow shock—PIC code—. MHD model. c Indian Academy of ..... Table 1. The solar wind input scaled parameters for the PIC and their corresponding values for the MHD code. Parameters. PIC code. GUMICS-v4. CPU time.

  1. 76 FR 65717 - City of Broken Bow, OK; Notice of Availability of Final Environmental Assessment

    Science.gov (United States)

    2011-10-24

    ... Energy Regulatory Commission City of Broken Bow, OK; Notice of Availability of Final Environmental Assessment In accordance with the National Environmental Policy Act of 1969 and the Federal Energy Regulatory... Forest. Staff prepared a final environmental assessment (EA), which analyzes the potential environmental...

  2. The Effect of Buffer Bow Structures on Collision Damages of Oil Tankers

    DEFF Research Database (Denmark)

    Yamada, Yasuhira; Pedersen, Preben Terndrup; Friis-Hansen, Peter

    2007-01-01

    SSCAT for collision scenarios where striking ships at various speeds, sizes and bulb shapes collide perpendicularly with a VLCC in fully loaded condition. The probability of oil spill from the struck VLCC in cases where all the striking ships use buffer bulbous bows was compared with the case where all...

  3. Tracing Sources Of Nitrate And Sulfate In The Bow River, Alberta Canada, Using Isotope Techniques

    Science.gov (United States)

    Chao, J.; Mayer, B.; Ryan, C.

    2009-05-01

    The Bow River in Alberta is a major tributary to the South Saskatchewan River in western Canada. Urban development and agricultural activities including feedlot operations within the Bow River Basin can potentially impact the river water quality by elevating nitrate and sulfate concentrations. In this project, we applied hydrological, chemical and isotopic techniques to identify sources of nitrate and sulfate in the Bow River. The study area stretches approximately 570km along the Bow River from Lake Louise in the Rocky Mountain headwaters to near its confluence with the Oldman River in the prairies. Between June 2007 and July 2008, monthly samples were taken from the Bow River for major ion chemistry and stable isotope ratio measurements of H, O, C, N and S. Flow data from Alberta Environment were used in combination with chemical data to estimate fluxes of nitrate, sulfate and other ionic solutes along the river. Isotope results show that Bow River water near Lake Louise was characterized by δ15N-NO3 values between 0 and +4‰ and δ18O-NO3 values between +7 and +11‰ falling within the range typical for nitrate produced by nitrification in forest ecosystems. Between Canmore and Calgary, δ15N- NO3 increased to values between +3 and +8‰, and δ18O-NO3 ranged between -5 and +5‰. Nitrate discharged from the Bonnybrook wastewater treatment plant in Calgary has elevated δ15N-NO3 values of +8‰ and low δ18O-NO3 values of -10‰. Nitrate flux increased over an order of magnitude in the river as a result of wastewater effluent discharge at Calgary. In the agricultural irrigation districts downstream of Calgary, δ15N-NO3 values varied between +6 and +11‰, whereas δ18O-NO3 values ranged between -11 and +1‰. The elevated δ15N-NO3 and low δ18O-NO3 values indicate that sewage derived nitrate from the wastewater treatment plant is the major cause for increased nitrate fluxes in the Bow River downstream of Calgary. At Lake Louise, δ34S-SO4 values varied

  4. Polarization signatures of bow shocks: A diagnostic tool to constrain the properties of stellar winds and ISM

    Science.gov (United States)

    Shrestha, Manisha; Hoffman, Jennifer L.; Nielson, Hilding R.; Ignace, Richard

    2017-01-01

    When a stellar wind traveling at supersonic speed interacts with almost stationary ISM, a bow shock shape is formed. By studying a bow shock, we can obtain information about the properties of the stellar wind as well as the surrounding ISM. Bow shocks are asymmetric structures, and thus produce net polarization even if they are unresolved. Hence, polarization studies of bow shocks can provide complementary constraints on their properties.We simulate the polarization signatures of circumstellar material with bow shock geometries using a Monte Carlo radiative transfer code called SLIP. We use the analytic solution from Wilkin (1996) to define the geometry and mass surface density of the bow shock in our models. We present results from our simulations showing how changing CSM optical depth, CSM albedo, photon source, and scattering particles (electrons or different types of dust particles) affects the observed polarization in both resolved and unresolved cases. In the optically thin regime of the unresolved electron-scattering case, the polarization peaks at an inclination angle of 90°, in agreement with analytical single-scattering models. In optically thick cases, a second polarization peak appears near 130°, which we propose is due to multiple scattering. Given these results, an observed polarization value can constrain the inclination of an unresolved bow shock to two possible angles, which in turn constrain the motion of the star. In case of resolved bow shocks, our simulations produce polarization maps which we compare with observations.We also present results from our dust-scattering simulations, which show that multicolor broadband polarization observations can constrain the characteristics of the dust in a resolved or unresolved bow shock-shaped CSM configuration.

  5. THE ROLE OF PICKUP IONS ON THE STRUCTURE OF THE VENUSIAN BOW SHOCK AND ITS IMPLICATIONS FOR THE TERMINATION SHOCK

    Energy Technology Data Exchange (ETDEWEB)

    Lu Quanming; Shan Lican; Zhang Tielong; Wu Mingyu; Wang Shui [CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary Science, University of Science and Technology of China, Hefei 230026 (China); Zank, Gary P. [Center for Space Plasma and Aeronomic Research (CSPAR), University of Alabama in Huntsville, Huntsville, AL 35899 (United States); Yang Zhongwei [SOA Key Laboratory for Polar Science, Polar Research Institute of China, Shanghai (China); Du Aimin, E-mail: qmlu@ustc.edu.cn [Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029 (China)

    2013-08-20

    The recent crossing of the termination shock by Voyager 2 has demonstrated the important role of pickup ions (PUIs) in the physics of collisionless shocks. The Venus Express (VEX) spacecraft orbits Venus in a 24 hr elliptical orbit that crosses the bow shock twice a day. VEX provides a unique opportunity to investigate the role of PUIs on the structure of collisionless shocks more generally. Using VEX observations, we find that the strength of the Venusian bow shock is weaker when solar activity is strong. We demonstrate that this surprising anti-correlation is due to PUIs mediating the Venusian bow shock.

  6. Bow shock models for the velocity structure of ultracompact H II regions

    Science.gov (United States)

    Van Buren, Dave; Mac Low, Mordecai-Mark

    1992-01-01

    The velocity structure of ultracompact H II regions is modeled assuming that O stars moving supersonically through molecular clouds sweep up bow shocks to produce the observed objects. The expected radio recombination line emission is calculated for the case of an optically thin continuum and the strong effect of changing the viewing angle is shown. The kinematic information removes the degeneracy with ram pressure of a previous model, allowing measurement of stellar velocity vectors and cloud densities. A detailed model for G29.96-0.02 shows good agreement with observations by Wood and Churchwell, supporting the bow shock hypothesis. It is found that the exciting star of G29 is moving at 20 km/s relative to the gas, suggesting that O stars acquire a large velocity dispersion early in their lives.

  7. MAVEN observations of gyrotropic electron distributions upstream of Mars bow shock

    Science.gov (United States)

    Meziane, Karim; McFadden, James; Hamza, A. M.; Mazelle, Christian; Jakosky, Bruce; Mitchell, David; Halekas, Jasper; Espley, Jared; Connerney, J. E. D.

    2016-07-01

    Recent observations upstream from the Martian bow shock by the MAVEN Solar Wind Electron Analyzer (SWEA) experiment are presented. Flux enhancements of electrons with energies 70-400 eV are always observed when MAVEN spacecraft is magnetically connected to the shock. A detailed examination of the pitch angle distribution shows that the enhanced fluxes are associated with electrons moving away from Mars. In the full 3-D angular distribution, the electrons appear in an 'annulus' centered along the IMF direction. Moreover, the gyrotropic character is observed over a large range of shock geometry from quasi-parallel to quasi-perpendicular. These signatures in the electron distribution function strongly suggest that the reflection off the shock is the main mechanism for the production of Martian foreshock electrons. A quantitative analysis of electron distributions is carried out in order to probe the characteristics of the Martian bow shock.

  8. ULF waves upstream of the Venus bow shock - Properties of one-hertz waves

    Science.gov (United States)

    Orlowski, D. S.; Russell, C. T.

    1991-01-01

    Pioneer Venus Orbiter data are used here to study the properties of a class of ULF upstream waves with relatively high observed frequencies. These waves show significant similarity to 'one-Hz' waves identified at earth in the ISEE 1 and 2 observations and the whistler waves identified earlier by IMP 6 observations. The waves appear almost immediately after the spacecraft crosses the magnetic field tangent line to the bow shock surface into the region of connected field lines. The wave amplitude decreases with distance from the shock measured along the magnetic field line. Group velocities calculated using the cold plasma dispersion relation indicate that the waves have sufficient upstream velocities to propagate form the shock into the solar wind. The totality of observations seem best explained by a source of right-handed whistler mode waves at the bow shock.

  9. Spatial scales of the magnetic ramp at the Venusian bow shock

    Directory of Open Access Journals (Sweden)

    A. P. Dimmock

    2011-11-01

    Full Text Available Typically multi-spacecraft missions are ideally suited to the study of shock spatial scales due to the separation of temporal and spatial variations. These missions are not possible at all locations and therefore in-situ multi-spacecraft measurements are not available beyond the Earth. The present paper presents a study of shock spatial scales using single spacecraft measurements made by the Venus Express spacecraft. The scales are determined based on previous knowledge of shock overshoot scales measured by the ISEE and Cluster missions. The study encompasses around 60 crossings of the Venusian bow shock from 2006 to 2009. The statistical relationship between the shock ramp spatial scales, overshoot and upstream shock parameters are investigated. We find that despite somewhat different solar wind conditions our results are comparable with those based on multi-spacecraft missions at the terrestrial bow shock.

  10. Characterization of Saturn's bow shock: Magnetic field observations of quasi-perpendicular shocks

    CERN Document Server

    Sulaiman, A H; Dougherty, M K

    2016-01-01

    Collisionless shocks vary drastically from terrestrial to astrophysical regimes resulting in radically different characteristics. This poses two complexities. Firstly, separating the influences of these parameters on physical mechanisms such as energy dissipation. Secondly, correlating observations of shock waves over a wide range of each parameter, enough to span across different regimes. Investigating the latter has been restricted since the majority of studies on shocks at exotic regimes (such as supernova remnants) have been achieved either remotely or via simulations, but rarely by means of in-situ observations. Here we present the parameter space of MA bow shock crossings from 2004-2014 as observed by the Cassini spacecraft. We find that Saturn's bow shock exhibits characteristics akin to both terrestrial and astrophysical regimes (MA of order 100), which is principally controlled by the upstream magnetic field strength. Moreover, we determined the {\\theta}Bn of each crossing to show that Saturn's (days...

  11. The Energetic Ion Events Measured Upstream the Earth's Bow Shock by STEREO, Cluster, ACE and Geotail: Where is the Origin?

    Science.gov (United States)

    Kronberg, E.; Bucik, R.; Haaland, S.; Klecker, B.; Daly, P. W.; Desai, M. I.; Yamauchi, M.; Gómez-Herrero, R.

    2009-12-01

    In earlier studies (e.g. Desai et al., 2008}) the observations of upstream events up to 3800 R_E were reported during declining phase of the solar cycle in 2007. These upstream events observed by STEREO-A mainly occurred after the corotating compression region passed the Earth's magnetosphere. We study the relation of these upstream events (from about 130 to 1600 R_E away from the Earth) with the observations in the direct vicinity of the terrestrial bow shock (up to X = 18 R_E). For this purpose simultaneous measurements of energetic ions with energies >30 keV by particle instruments onboard STEREO-A, STEREO-B, ACE (far upstream region), and onboard Cluster and Geotail (the direct vicinity of the bow shock) are used. The upstream events are observed simultaneously mainly when the magnetic field is pointing along the line joining those satellites in far upstream region with those near the terrestrial bow shock. Therefore the connection of the magnetic field to the bow shock plays an important role for the occurrence of the many energetic events far upstream. Nevertheless there is a number of energetic events whose origin seems not to be connected to the terrestrial bow shock. Using the estimation of the propagation time of solar wind discontinuities we show that these energetic events convect together with the solar wind, pass the upstream region of the Earth's bow shock and trigger the upstream events in the vicinity of the bow shock, not the other way around. The ion intensity observed by STEREO-A and STEREO-B in these cases is often significantly higher than that observed in front of the bow shock by Cluster and Geotail. This suggests that, particles are accelerated in the solar wind, possibly by enhanced wave activity in high speed streams and corotating interaction regions (CIR).

  12. Observation of Motion of Bowed Strings and Resonant Strings in Violin Performances

    Science.gov (United States)

    Matsutani, Akihiro

    2013-10-01

    The motion of a bowed string and a resonant string of a violin were simultaneously observed for the first time. The results of the direct observation of string motion in double stops and harmonics are also presented. The importance of the resonance was experimentally demonstrated from these observations. It is suggested that players should take account of the resonance and ideal Helmholtz motion in violin performances.

  13. [A drill-bow in Horace, Odes 3.6.7].

    Science.gov (United States)

    Moog, Ferdinand Peter

    2004-01-01

    With the short poem Odes 3.26 Horaces says--ostensibly--farewell to the subject of love. A symbol of his retreat is the order given to his followers: they ought to lay in the Temple of Venus the three objects which he has used in his night escapades struggling for the girls' love: lucida funalia (torches), vectis (jemmies), and arcus. The last words has been puzzling the scholars for centuries. Many took offence at the transmitted text and offered conjectures of their own. Some, however, defended arcus using different arguemtns, for instance that arcus refers to bows and arrows as weapons of the lascivious night-reveller. Also the author of this article retains arcus in the text. The context and grammatical construction let assume that also this noun denotes a tool of a burglar, preferably a drill driven by a fiddle-bow. Such instruments were use by carpenters, joiners, and surgeons. Apart from this, gigantic drill-bows were known among military machines. These were frequently applied in sieges. Horace might have seen descriptions and drawings of them in military handbooks which he presumably read in order to prepare himself for his short and rather inglorious career as an officer in the army of Caesar's murderers. For Romans without military experience who suddenly obtained a high rank at war this was a typical way of making good their shortcomings. The parallel between the siege of a town and the attack upon the beloved girl's house must be regarded as a poetic exaggeration; the reader should be amused by an impracticable idea. Furthermore, a possible connection between Horace's poem and the Heracles of Euripides is pointed out here for the first time. In Heracles 942-6 the hero, driven insane by Lyssa's work, asks for his bow, his arrows and siege instruments to take Mycenae, the fortress of his tormentor Eurystheus. In fact he brakes into his own bedroom and kills his spouse and his son.

  14. Self-assembled silver nanoparticles in a bow-tie antenna configuration.

    Science.gov (United States)

    Eskelinen, Antti-Pekka; Moerland, Robert J; Kostiainen, Mauri A; Törmä, Päivi

    2014-03-26

    The self-assembly of silver nanoparticles into a bow-tie antenna configuration is achieved with the DNA origami method. Instead of complicated particle geometries, spherical silver nanoparticles are used. Formation of the structures in high yields is verified with transmission electron microscopy and agarose gel electrophoresis. According to finite-difference time-domain simulations, the antenna configuration could be used as a DNA sensor.

  15. Increase The Absorptive Capacity Of Light Of The Photocells By Embedded In Bow-tie Antenna

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Chenguang [School of Science, Beijing University of Posts and Telecommunications, Beijing, 100876 (China); Lang Peilin [Key Laboratory of Information Photonics and Optical Communications (BUPT), Ministry of Education, Beijing 100876 (China); Zhang Ru, E-mail: napolles@sohu.com

    2011-02-01

    The application of silicon photocells has been widely used in biological and energy field, how to improve the efficiency of silicon photocells has become the research hot spots. The light absorption efficiency is not ideal, only 10% to 20% of solar energy can be transformed into electricity, the paper embeds metal bow-tie antenna in the crystals of silicon, by the field enhancement of the surface plasma, it highly increase the absorptive capacity of light of the silicon photocells.

  16. Variation of the ratio of specific heats across a detached bow shock

    Science.gov (United States)

    Chao, J. K.; Wiskerchen, M. J.

    1974-01-01

    Equations are derived which allow the ratio of specific heats behind the earth's bow shock to be evaluated if several pre-shock parameters (the specific-heat ratio, the Alfvenic Mach number, the sonic Mach number, and the angle between the shock normal at the stagnation point and the magnetic field) and the density jump across the shock are known. Numerical examples show that the dependence of the post-shock ratio on the pre-shock ratio is weak.

  17. Phenomenology of the earth's bow shock system - A summary description of experimental results

    Science.gov (United States)

    Greenstadt, E. W.

    1976-01-01

    Observational data on the earth's bow shock system are classified and characterized. Foreshock components, midshock components, and aftershock components are discussed separately. Schematic representations of the field and plasma particle parameters are elaborated, with attention given to quasi-perpendicular geometry and quasi-parallel geometry. Magnetic pulsation structure is delineated. Schematic profiles of field, particle, and wave behavior through a representative quasi-perpendicular shock crossing are displayed.

  18. Farby-Perot observations and new models of the HH 47A and HH 47D bow shocks

    Science.gov (United States)

    Morse, Jon A.; Hartigan, Patrick; Heathcote, Steve; Raymond, John C.; Cecil, Gerald

    1994-01-01

    We present new models for the HH 47A and HH 47D bow shocks based on line flux and velocity maps obtained with an imaging Fabry-Perot spectrometer. We confirm that HH 47A and HH 47D each show a bow shock/Mach disk morphology, and that velocity variability in the outflow can account for the observed structures. While it was suggested a decade ago that the inner working surface HH 47A appears to be traveling into the wake of HH 47D, we find kinematic evidence that the outer bow shock HH 47D is also not the primary ejection event in the outflow but follows in the wake of previously ejected material. By comparing the observed line ratios and line profiles to those predicted by our bow shock models, we find that both bow shocks have substantially lower shock velocities than their space motions would imply, and that the emission from each bow shock is systematically blueshifted from the rest-frame velocity of the ambient emission, indicating a comoving preshock medium. We derive kinematic ages of approximately 1150 yr for HH 47D and approximately 550 yr for HH 47A, which implies that the stellar driving source may undergo repetitive eruptions similar to FU Orionis-type outbursts every several hundred years. This timescale is similar to estimates made by Reipurth and collaborators for the separation between major outbursts in the HH 34 and HH 111 stellar jets.

  19. Ship Bow Force-Deformation Curves for Ship-Impact Demand of Bridges considering Effect of Pile-Cap Depth

    Directory of Open Access Journals (Sweden)

    Wei Fan

    2014-01-01

    Full Text Available Since static analysis procedures in the vessel impact-resistant design codes neglect dynamic amplification effects related to bridge mass, ship-impact responses of bridges may be potentially underestimated. For this reason, several dynamic vessel-impact analysis techniques had been recently proposed, where a force-deformation curve was employed to model the vessel bow stiffness. Most of the recent works mainly focused on the force-deformation curves of the barge bows rather than the ship bows. In this paper, a high-resolution finite element model is developed to obtain the ship bow force-deformation curves. The global and local characteristics of the ship bow force-deformation curves are discussed based on the finite element crush analyses between the ship bows and the rigid walls. Effect of pile-cap depth on the force-deformation curves (rather than only impact forces is studied in detail, and the corresponding empirical equations are developed using an energy ratio method. Finally, a practical example of ship-bridge collision is investigated to validate the force-deformation curves considering the effect of pile-cap depth. It is found from the case study that the effect of pile-cap depth plays an important role in quantifying structural demand under impact loads. The case study also indicates that the developed equations are reasonable in practical applications.

  20. The structure of bow shocks formed by the interaction of pulsed-power driven magnetised plasma flows with conducting obstacles

    Science.gov (United States)

    Burdiak, G. C.; Lebedev, S. V.; Bland, S. N.; Clayson, T.; Hare, J.; Suttle, L.; Suzuki-Vidal, F.; Garcia, D. C.; Chittenden, J. P.; Bott-Suzuki, S.; Ciardi, A.; Frank, A.; Lane, T. S.

    2017-07-01

    We present an experimental study of the development and structure of bow shocks produced by the interaction of a magnetised, collisional, super-Alfvénic plasma flow with conducting cylindrical obstacles. The plasma flow with an embedded, frozen-in magnetic field (ReM ˜ 20) is produced by the current-driven ablation of fine aluminium wires in an inverse, exploding wire array z-pinch. We show that the orientation of the embedded field with respect to the obstacles has a dramatic effect on the bow shock structure. When the field is aligned with the obstacle, a sharp bow shock is formed with a global structure that is determined simply by the fast magneto-sonic Mach number. When the field is orthogonal to the obstacle, magnetic draping occurs. This leads to the growth of a magnetic precursor and the subsequent development of a magnetised bow shock that is mediated by two-fluid effects, with an opening angle and a stand-off distance, that are both many times larger than in the parallel geometry. By changing the field orientation, we change the fluid regime and physical mechanisms that are responsible for the development of the bow shocks. MHD simulations show good agreement with the structure of well-developed bow shocks. However, collisionless, two-fluid effects will need to be included within models to accurately reproduce the development of the shock with an orthogonal B-field.

  1. Interactions of massive stars with the interstellar medium: Bow shocks and superbubbles

    Energy Technology Data Exchange (ETDEWEB)

    Maclow, M.

    1989-01-01

    Stellar winds and supernovae from massive stars carry most of the energy transferred from stars to the interstellar medium. The structures created by these processes reveal glimpses of the movement of mass between stars and the galactic ecological cycle. Two such structures are modeled bow shocks and superbubbles. Multiple supernovae and winds from OB associations carve large holes filled with hot gas in the galactic disk. These superbubbles sweep up thin, cold, dense shells that eventually grow large enough to blow out of the disk, venting hot gas into the galactic halo. To model superbubbles, the blast waves from supernovae within them are analytically described, showing they become subsonic before reaching the walls or cooling radiatively. The Kompaneets or thin-shell approximation are used to numerically model the growth of superbubbles in stratified disks until they become Raleigh-Taylor unstable. ZEUS, a two-dimensional hydrodynamics code was used to follow the breakup of the shell. The differences between the results and previous models are explained. Considering stars with strong winds leads to an explanation for ultracompact H II regions (USHRs). It was proposed that UCHRs are trapped in bow shocks swept up by the winds of massive stars moving supersonically through molecular clouds. A thin shell approximation was used to find the shape of such bow shocks. Simulated maps were produced and compared to G12.21 - 0.01, G29.96 - 0.02, G34.26 + 0.15, and G43.89 - 0.78.

  2. Risk analysis of urban gas pipeline network based on improved bow-tie model

    Science.gov (United States)

    Hao, M. J.; You, Q. J.; Yue, Z.

    2017-11-01

    Gas pipeline network is a major hazard source in urban areas. In the event of an accident, there could be grave consequences. In order to understand more clearly the causes and consequences of gas pipeline network accidents, and to develop prevention and mitigation measures, the author puts forward the application of improved bow-tie model to analyze risks of urban gas pipeline network. The improved bow-tie model analyzes accident causes from four aspects: human, materials, environment and management; it also analyzes the consequences from four aspects: casualty, property loss, environment and society. Then it quantifies the causes and consequences. Risk identification, risk analysis, risk assessment, risk control, and risk management will be clearly shown in the model figures. Then it can suggest prevention and mitigation measures accordingly to help reduce accident rate of gas pipeline network. The results show that the whole process of an accident can be visually investigated using the bow-tie model. It can also provide reasons for and predict consequences of an unfortunate event. It is of great significance in order to analyze leakage failure of gas pipeline network.

  3. High-Energy-Density, Laboratory-Astrophysics Studies of Jets and Bow Shocks

    Energy Technology Data Exchange (ETDEWEB)

    Foster, J M; Wilde, B H; Rosen, P A; Perry, T S; Khokhlov, A M; Coker, R F; Frank, A; Keiter, P A; Blue, B E; Drake, R P; Knauer, J P; Williams, R R

    2005-01-24

    Large-scale directional outflows of supersonic plasma, also known as ''jets'', are ubiquitous phenomena in astrophysics [1]. The interaction of such jets with surrounding matter often results in spectacular bow shocks, and intense radiation from radio to gamma-ray wavelengths. The traditional approach to understanding such phenomena is through theoretical analysis and numerical simulations. However, such numerical simulations have limited resolution, often assume axial symmetry, do not include all relevant physical processes, and fail to scale correctly in Reynolds number and perhaps other key dimensionless parameters. Additionally, they are frequently not tested by comparison with laboratory experiments. Recent advances in high-energy-density physics using large inertial-confinement-fusion devices now allow controlled laboratory experiments on macroscopic volumes of plasma of direct relevance relevant to astrophysics [2]. In this Letter we report the first results of experiments designed to study the evolution of supersonic plasma jets and the bow shocks they drive into a surrounding medium. Our experiments reveal both regular and highly complex flow patterns in the bow shock, thus opening a new window--complementary to computer simulations--into understanding the nature of three-dimensional astrophysical jets.

  4. The Asymmetric Bow Shock/Pulsar Wind Nebula of PSR J2124–3358

    Science.gov (United States)

    Romani, Roger W.; Slane, Patrick; Green, Andrew W.

    2017-12-01

    We describe new measurements of the remarkable Hα/UV/X-ray bow shock and pulsar wind nebula (PWN) of the isolated millisecond pulsar (MSP) PSR J2124‑3358. Chandra X-ray Observatory imaging shows a one-sided jet structure with a softer equatorial outflow. KOALA integral field unit spectroscopy shows that non-radiative emission dominates the bow shock and that the Hα nebula is asymmetric about the pulsar velocity with an elongation into the plane of the sky. We extend analytic models of the contact discontinuity to accommodate such shapes and compare these to the data. Using Hubble Space Telescope UV detections of the pulsar and bow shock, radio timing distance, proper motion measurements, and the CXO-detected projected spin axis, we model the 3D PWN momentum flux distribution. The integrated momentum flux depends on the ionization of the ambient ISM, but for an expected ambient warm neutral medium, we infer I=2.4× {10}45 {{g}} {{cm}}2. This implies {M}{NS}=1.6{--}2.1 {M}ȯ , depending on the equation of state, which in turn suggests that the MSP gained significant mass during recycling and then lost its companion. However, this conclusion is at present tentative, since lower ionization allows ∼ 30 % lower masses, and uncertainty in the parallax allows up to 50% error.

  5. Interaction of single-pulse laser energy with bow shock in hypersonic flow

    Directory of Open Access Journals (Sweden)

    Hong Yanji

    2014-04-01

    Full Text Available Pressure sensing and schlieren imaging with high resolution and sensitivity are applied to the study of the interaction of single-pulse laser energy with bow shock at Mach 5. An Nd:YAG laser operated at 1.06 μm, 100 mJ pulse energy is used to break down the hypersonic flow in a shock tunnel. Three-dimensional Navier–Stokes equations are solved with an upwind scheme to simulate the interaction. The pressure at the stagnation point on the blunt body is measured and calculated to examine the pressure variation during the interaction. Schlieren imaging is used in conjunction with the calculated density gradients to examine the process of the interaction. The results show that the experimental pressure at the stagnation point on the blunt body and schlieren imaging fit well with the simulation. The pressure at the stagnation point on the blunt body will increase when the transmission shock approaches the blunt body and decrease with the formation of the rarefied wave. Bow shock is deformed during the interaction. Quasi-stationary waves are formed by high rate laser energy deposition to control the bow shock. The pressure and temperature at the stagnation point on the blunt body and the wave drag are reduced to 50%, 75% and 81% respectively according to the simulation. Schlieren imaging has provided important information for the investigation of the mechanism of the interaction.

  6. Magnetosheath Filamentary Structures Formed by Ion Acceleration at the Quasi-Parallel Bow Shock

    Science.gov (United States)

    Omidi, N.; Sibeck, D.; Gutynska, O.; Trattner, K. J.

    2014-01-01

    Results from 2.5-D electromagnetic hybrid simulations show the formation of field-aligned, filamentary plasma structures in the magnetosheath. They begin at the quasi-parallel bow shock and extend far into the magnetosheath. These structures exhibit anticorrelated, spatial oscillations in plasma density and ion temperature. Closer to the bow shock, magnetic field variations associated with density and temperature oscillations may also be present. Magnetosheath filamentary structures (MFS) form primarily in the quasi-parallel sheath; however, they may extend to the quasi-perpendicular magnetosheath. They occur over a wide range of solar wind Alfvénic Mach numbers and interplanetary magnetic field directions. At lower Mach numbers with lower levels of magnetosheath turbulence, MFS remain highly coherent over large distances. At higher Mach numbers, magnetosheath turbulence decreases the level of coherence. Magnetosheath filamentary structures result from localized ion acceleration at the quasi-parallel bow shock and the injection of energetic ions into the magnetosheath. The localized nature of ion acceleration is tied to the generation of fast magnetosonic waves at and upstream of the quasi-parallel shock. The increased pressure in flux tubes containing the shock accelerated ions results in the depletion of the thermal plasma in these flux tubes and the enhancement of density in flux tubes void of energetic ions. This results in the observed anticorrelation between ion temperature and plasma density.

  7. Effect of an isotropic outflow from the Galactic Centre on the bow-shock evolution along the orbit

    Science.gov (United States)

    Zajaček, M.; Eckart, A.; Karas, V.; Kunneriath, D.; Shahzamanian, B.; Sabha, N.; Mužić, K.; Valencia-S., M.

    2016-01-01

    Motivated by the observations of several infrared-excess bow-shock sources and proplyd-like objects near the Galactic Centre, we analyse the effect of a potential outflow from the centre on bow-shock properties. We show that due to the non-negligible isotropic central outflow the bow-shock evolution along the orbit becomes asymmetric between the pre-peribothron and post-peribothron phases. This is demonstrated by the calculation of the bow-shock size evolution, the velocity along the shocked layer, the surface density of the bow shock, and by emission-measure maps close to the peribothron passage. Within the ambient velocity range of ≲2000 km s-1 the asymmetry is profound and the changes are considerable for different outflow velocities. As a case study we perform model calculations for the Dusty S-cluster Object (DSO/G2) as a potential young stellar object that is currently being monitored and has passed the pericentre at ˜2000 Schwarzschild radii from the supermassive black hole (Sgr A*) in 2014. We show that the velocity field of the shocked layer can contribute to the observed increasing line width of the DSO source up to the peribothron. Subsequently, supposing that the line emission originates in the bow shock, a decrease of the line width is expected. Furthermore, the decline of the bow-shock emission measure in the post-peribothron phase could help to reveal the emission of the putative star. The dominant contribution of circumstellar matter (either inflow or outflow) is consistent with the observed stable luminosity and compactness of the DSO/G2 source during its pericentre passage.

  8. Martian Bow Shock and Magnetic Pile-Up Barrier Formation Due to the Exosphere Ion Mass-Loading

    Directory of Open Access Journals (Sweden)

    Eojin Kim

    2011-03-01

    Full Text Available Bow shock, formed by the interaction between the solar wind and a planet, is generated in different patterns depending on the conditions of the planet. In the case of the earth, its own strong magnetic field plays a critical role in determining the position of the bow shock. However, in the case of Mars of which has very a small intrinsic magnetic field, the bow shock is formed by the direct interaction between the solar wind and the Martian ionosphere. It is known that the position of the Martian bow shock is affected by the mass loading-effect by which the supersonic solar wind velocity becomes subsonic as the heavy ions originating from the planet are loaded on the solar wind. We simulated the Martian magnetosphere depending on the changes of the density and velocity of the solar wind by using the three-dimensional magnetohydrodynamic model built by modifying the comet code that includes the mass loading effect. The Martian exosphere model of was employed as the Martian atmosphere model, and only the photoionization by the solar radiation was considered in the ionization process of the neutral atmosphere. In the simulation result under the normal solar wind conditions, the Martian bow shock position in the subsolar point direction was consistent with the result of the previous studies. The three-dimensional simulation results produced by varying the solar wind density and velocity were all included in the range of the Martian bow shock position observed by Mariner 4, Mars 2, 3, 5, and Phobos 2. Additionally, the simulation result also showed that the change of the solar wind density had a greater effect on the Martian bow shock position than the change of the solar wind velocity. Our result may be useful in analyzing the future observation data by Martian probes.

  9. ANALISA OLAH GERAK KAPAL DI GELOMBANG REGULER PADA KAPAL TIPE AXE BOW

    Directory of Open Access Journals (Sweden)

    Romadhoni Romadhoni

    2016-10-01

    Full Text Available Kapal dengan tipe AXE BOW merupakan pengembangan dari Inovasi Enlarged ship Concept yang di desain dan dikembangkan pada tahun 1995 oleh Delft University dan Damen Shipyard. Konsep Axe- Bow sendiri merupakan re-design bentuk haluan kapal yang pada penelitian sebelumnya dapat memberikan nilai hambatan yang lebih rendah dibandingan haluan tanpa bentuk Axe Bow.  Pada penelitian ini menganalisa tentang enam derajat kebebasan, khususnya pada gerakan vertikal yaitu heaving, pitching dan rolling pada gelombang reguler yang disajikan dalam grafik Response Amplitudo Operator (RAO’s. dengan memasukkan parameter seperti variasi kecepatan serta sudut gelombang yaitu 0°,45°,90° dan 180° kemudian dari grafik dapat terlihat nilai sub-kritis, kritis dan sangat kritis pada setiap gerakan. Perhitungan dilakukan dengan bantuan komputasi software Seakeeper ver.13, Hasil penelitian ini adalah nilai gerakan heave maksimum terjadi pada saat kecepatan 12.68 m/s kondisi sudut datang gelombang 180° dengan nilai RAO sebesar 2,54 m/m pada frekuensi 0,95 rad/s. Selanjutnya terjadi penurunan nilai gerakan roll seiring dengan bertambahnya kecepatan kapal. Nilai roll maksimum terjadi sudut datang gelombang 90° saat kecepatan kapal 0/ms dengan nilai RAO 15.5 deg/m pada frekuensi 0,95 rad/s, sedangkan nilai roll minimum terjadi pada kecepatan 12.68 m/s dengan sudut datang 90o nilai RAO 15.04 deg/m. pada fekuensi 1.25 rad/s. dan gerakan pith maksimum terjadi pada kecepatan kapal 12.68 m/s arah gelombang 180o dengan nilai RAO 11.29 deg/m pada frekuensi 1.0 rad/s.

  10. Analytic MHD Theory for Earth's Bow Shock at Low Mach Numbers

    Science.gov (United States)

    Grabbe, Crockett L.; Cairns, Iver H.

    1995-01-01

    A previous MHD theory for the density jump at the Earth's bow shock, which assumed the Alfven M(A) and sonic M(s) Mach numbers are both much greater than 1, is reanalyzed and generalized. It is shown that the MHD jump equation can be analytically solved much more directly using perturbation theory, with the ordering determined by M(A) and M(s), and that the first-order perturbation solution is identical to the solution found in the earlier theory. The second-order perturbation solution is calculated, whereas the earlier approach cannot be used to obtain it. The second-order terms generally are important over most of the range of M(A) and M(s) in the solar wind when the angle theta between the normal to the bow shock and magnetic field is not close to 0 deg or 180 deg (the solutions are symmetric about 90 deg). This new perturbation solution is generally accurate under most solar wind conditions at 1 AU, with the exception of low Mach numbers when theta is close to 90 deg. In this exceptional case the new solution does not improve on the first-order solutions obtained earlier, and the predicted density ratio can vary by 10-20% from the exact numerical MHD solutions. For theta approx. = 90 deg another perturbation solution is derived that predicts the density ratio much more accurately. This second solution is typically accurate for quasi-perpendicular conditions. Taken together, these two analytical solutions are generally accurate for the Earth's bow shock, except in the rare circumstance that M(A) is less than or = 2. MHD and gasdynamic simulations have produced empirical models in which the shock's standoff distance a(s) is linearly related to the density jump ratio X at the subsolar point. Using an empirical relationship between a(s) and X obtained from MHD simulations, a(s) values predicted using the MHD solutions for X are compared with the predictions of phenomenological models commonly used for modeling observational data, and with the predictions of a

  11. Multispacecraft observations of the terrestrial bow shock and magnetopause during extreme solar wind disturbances

    DEFF Research Database (Denmark)

    Tatrallyay, M.; Erdos, G.; Nemeth, Z.

    2012-01-01

    by the interplanetary magnetic field (IMF) component transverse to the solar wind flow. The observed magnetopause crossings could be predicted with a reasonable accuracy (0.1-0.2 RE) by one of the presented models at least. For geosynchronous magnetopause crossings observed by the GOES satellites, (1) the new model...... interplanetary disturbances. The results of a global 3-D MHD model were in good agreement with the Cluster observations on 17 January 2005, but they did not predict the bow shock crossings on 31 October 2003....

  12. Beam-Steerable Microstrip-Fed Bow-Tie Antenna Array for Fifth Generation Cellular Communications

    DEFF Research Database (Denmark)

    Ojaroudiparchin, Naser; Shen, Ming; Pedersen, Gert Frølund

    2016-01-01

    The design and performance of mm-wave phased array antenna for 5G mobile broadband communication systems has been provided in this manuscript. The antenna is designed on a N9000 PTFE substrate with 0.787 mm thickness and 2.2 dielectric constant and 65×130 mm2 overall dimension. Eight elements...... of bow-tie antennas have been used at the top-edge region of mobile phone PCB. The antenna elements fed by microstrip lines are designed to operate at 17 GHz. The simulated results give good performances in terms of different antenna parameters. In addition, an investigation on the distance between...

  13. Estimation of violin bowing features from Audio recordings with Convolutional Networks

    DEFF Research Database (Denmark)

    Perez-Carillo, Alfonso; Purwins, Hendrik

    2017-01-01

    . However, the acquisition process usually involves the use of expensive sensing systems and complex setups that are generally intrusive in practice. An alternative to direct acquisition is through the analysis of the audio signal. So called indirect acquisition has many advantages including the simplicity...... and low-cost of the acquisition and its nonintrusive nature. The main challenge is designing robust detection algorithms to be as accurate as the direct approaches. In this paper, we present an indirect acquisition method to estimate violin bowing controls from audio signal analysis based on training...

  14. Dynamics of ion sound waves in the front of the terrestrial bow shock

    Directory of Open Access Journals (Sweden)

    I. Giagkiozis

    2011-05-01

    Full Text Available Single spacecraft measurements from the Cluster 3 satellite are used to identify nonlinear processes in ion-sound turbulence observed within the front of the quasiperpendicular terrestrial bow shock. Ion sound waves possess spatial scales that are too small for the efficient use of multipoint measurements on inter-satellite separation scales. However, it is shown how frequency domain modelling can be applied to single spacecraft electric field data obtained using the EFW internal burst mode. The resulting characteristics of the nonlinear processes are used to argue about the possible wave sources and investigate their dynamics.

  15. Archery by the Apaches – implications of using the bow and arrow in hunter-gatherer communities

    Directory of Open Access Journals (Sweden)

    Žiga Šmit

    2016-12-01

    Full Text Available This review focuses on the technical and social details of production, training, and use of archery equipment by a Native American tribe, the Apaches. The study aims to understand the use of the bow in the Mesolithic and Early and Middle Neolithic societies of the Old World. The paper further describes arrow ballistics. An arrow and bow with similar dimensions and materials to those used by the Apaches was reconstructed and used in ballistic experiments. Shooting and the subsequent model calculation showed that the effective range of arrows made of reed and projected by a bow of medium strength (16–18kg was not more than approx. 20m. Due to the initial flat part of the ballistic trajectory, such arrows were quite efficient in close-range contests. Within the model calculation, a regression procedure was introduced to determine the arrow air-drag parameters from an ensemble of shots.

  16. Cometary compact H II regions are stellar-wind bow shocks

    Energy Technology Data Exchange (ETDEWEB)

    Van Buren, D.; Mac Low, M.; Wood, D.O.S.; Churchwell, E. (Johns Hopkins Univ., Baltimore, MD (USA) Canadian Institute for Theoretical Astrophysics, Toronto (Canada) NASA, Ames Research Center, Moffett Field, CA (USA) Joint Institute for Laboratory Astrophysics, Boulder, CO (USA) Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (USA) Washburn Observatory, Madison, WI (USA))

    1990-04-01

    Comet-shaped H II regions, like G34.3 + 0.2, are easily explained as bow shocks created by wind-blowing massive stars moving supersonically through molecular clouds. The required velocities of the stars through dense clumps are less than about 10 km/s, comparable to the velocity dispersion of stars in OB associations. An analytic model of bow shocks matches the gross characteristics seen in the radio continuum and the velocity structure inferred from hydrogen recombination and molecular line observations. The champagne flow model cannot account for these structures. VLBI observations of masers associated with the shells of cometary compact H II regions should reveal tailward proper motions predominantly parallel to the shell, rather than perpendicular. It is predicted that over a decade baseline, high signal-to-noise VLA observations of this class of objects will show headward pattern motion in the direction of the symmetry axis, but not expansion. Finally, shock-generated and coronal infrared lines are also predicted. 57 refs.

  17. Simulation study of magnetic holes at the Earth's collisionless bow shock

    Energy Technology Data Exchange (ETDEWEB)

    Eliasson, B; Shukla, P K [Institut fuer Theoretische Physik IV, Fakultaet fuer Physik und Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany); Department of Physics, Umeaa University, SE-90187 Umeaa (Sweden)

    2007-06-15

    Recent observations by the Cluster and Double Star spacecraft at the Earth's bow shock have revealed localized magnetic field and density holes in the solar wind plasma. These structures are characterized by a local depletion of the magnetic field and the plasma density, and by a strong increase of the plasma temperature inside the magnetic and density cavities. Our objective here is to report results of a hybrid-Vlasov simulations of ion-Larmor-radius sized plasma density cavities with parameters that are representative of the high-beta solar wind plasma at the Earth's bow shock. We observe the asymmetric self-steepening and shock-formation of the cavity, and a strong localized temperature increase (by a factor of 5-7) of the plasma due to reflections and shock surfing of the ions against the collisionless shock. Temperature maxima are correlated with density minima, in agreement with Cluster observations. For oblique incidence of the solar wind, we observe efficient acceleration of ions along the magnetic field lines by the shock drift acceleration process.

  18. Ionospheric Bow Waves and Perturbations Induced by the 21 August 2017 Solar Eclipse

    Science.gov (United States)

    Zhang, Shun-Rong; Erickson, Philip J.; Goncharenko, Larisa P.; Coster, Anthea J.; Rideout, William; Vierinen, Juha

    2017-12-01

    During solar eclipses, the Moon's shadow causes a large reduction in atmospheric energy input, including not only the stratosphere but also the thermosphere and ionosphere. The eclipse shadow has a supersonic motion which is theoretically expected to generate atmospheric bow waves, similar to a fast-moving river boat, with waves starting in the lower atmosphere and propagating into the ionosphere. However, previous geographically limited observations have had difficulty detecting these weak waves within the natural background atmospheric variability, and the existence of eclipse-induced ionospheric waves and their evolution in a complex coupling system remain controversial. During the 21 August 2017 eclipse, high fidelity and wide coverage ionospheric observations provided for the first time an oversampled set of eclipse data, using a dense network of Global Navigation Satellite System receivers at ˜2,000 sites in North America. We show the first unambiguous evidence of ionospheric bow waves as electron content disturbances over central/eastern United States, with ˜1 h duration, 300-400 km wavelength and 280 m/s phase speed emanating from and tailing the totality region. We also identify large ionospheric perturbations moving at the supersonic speed of the maximum solar obscuration which are too fast to be associated with known gravity wave or large-scale traveling ionospheric disturbance processes. This study reveals complex interconnections between the Sun, Moon, and Earth's neutral atmosphere and ionosphere and demonstrates persistent coupling processes between different components of the Earth's atmosphere, a topic of significant community interest.

  19. Compound semiconductor alloys: From atomic-scale structure to bandgap bowing

    Science.gov (United States)

    Schnohr, C. S.

    2015-09-01

    Compound semiconductor alloys such as InxGa1-xAs, GaAsxP1-x, or CuInxGa1-xSe2 are increasingly employed in numerous electronic, optoelectronic, and photonic devices due to the possibility of tuning their properties over a wide parameter range simply by adjusting the alloy composition. Interestingly, the material properties are also determined by the atomic-scale structure of the alloys on the subnanometer scale. These local atomic arrangements exhibit a striking deviation from the average crystallographic structure featuring different element-specific bond lengths, pronounced bond angle relaxation and severe atomic displacements. The latter, in particular, have a strong influence on the bandgap energy and give rise to a significant contribution to the experimentally observed bandgap bowing. This article therefore reviews experimental and theoretical studies of the atomic-scale structure of III-V and II-VI zincblende alloys and I-III-VI2 chalcopyrite alloys and explains the characteristic findings in terms of bond length and bond angle relaxation. Different approaches to describe and predict the bandgap bowing are presented and the correlation with local structural parameters is discussed in detail. The article further highlights both similarities and differences between the cubic zincblende alloys and the more complex chalcopyrite alloys and demonstrates that similar effects can also be expected for other tetrahedrally coordinated semiconductors of the adamantine structural family.

  20. Diversity of sponges (Porifera) from cryptic habitats on the Belize barrier reef near Carrie Bow Cay.

    Science.gov (United States)

    Rützler, Klaus; Piantoni, Carla; Van Soest, Rob W M; Díaz, M Cristina

    2014-05-29

    The Caribbean barrier reef near Carrie Bow Cay, Belize, has been a focus of Smithsonian Institution (Washington) reef and mangrove investigations since the early 1970s. Systematics and biology of sponges (Porifera) were addressed by several researchers but none of the studies dealt with cryptic habitats, such as the shaded undersides of coral rubble, reef crevices, and caves, although a high species diversity was recognized and samples were taken for future reference and study. This paper is the result of processing samples taken between 1972 and 2012. In all, 122 species were identified, 14 of them new (including one new genus). The new species are Tetralophophora (new genus) mesoamericana, Geodia cribrata, Placospongia caribica, Prosuberites carriebowensis, Timea diplasterina, Timea oxyasterina, Rhaphidhistia belizensis, Wigginsia curlewensis, Phorbas aurantiacus, Myrmekioderma laminatum, Niphates arenata, Siphonodictyon occultum, Xestospongia purpurea, and Aplysina sciophila. We determined that about 75 of the 122 cryptic sponge species studied (61%) are exclusive members of the sciophilic community, 47 (39 %) occur in both, light-exposed and shaded or dark habitats. Since we estimate the previously known sponge population of Carrie Bow reefs and mangroves at about 200 species, the cryptic fauna makes up 38 % of total diversity.

  1. Modeling plasma glow discharges in Air near a Mach 3 bow shock with KRONOS

    Science.gov (United States)

    Rassou, Sebastien; Labaune, Julien; Packan, Denis; Elias, Paul-Quentin

    2016-09-01

    In this work, plasma glow discharge in Air is modeled near a Mach 3 bow shock. Numerical simulations are performed using the coupling KRONOS which have been developed at ONERA. The flow field is modeled using the code CFD: CEDRE from ONERA and the electrical and plasma part by the EDF open-source code CODE_SATURNE. The plasma kinetic modeling consists on a two-term Boltzmann equation solver and a chemical reaction solver depending of the electric field. The coupling KRONOS is fully parallelized and run on ONERA supercomputers. The shock wave is formed by the propagation of a supersonic flow (M = 3) through a truncated conical model mounted with a central spike. Depending on the spike's voltage value, corona, glow or arc regime could be obtained in a steady flow. The parameters for the supersonic flow and the spike configurations are chosen to be in glow discharge regime and to reproduce the experimental setup. In our simulations, 12 species and 80 reactions (ionization, electronic or vibrational excitation, attachment etc ...) are considered to properly model the glow discharge and the afterglow. In a stationary flow, glow discharge is observed only at the upstream of the shock wave near the high voltage spike. Behind the bow shock, in the afterglow, negative ions are provided by electrons attachment with O2. The negative ions flow convection ensures the electrical conduction and the establishment of the glow discharge.

  2. Woods with physical, mechanical and acoustic properties similar to those of Caesalpinia echinata have high potential as alternative woods for bow makers

    Directory of Open Access Journals (Sweden)

    Eduardo Luiz Longui

    2014-09-01

    Full Text Available For nearly two hundred years, Caesalpinia echinata wood has been the standard for modern bows. However, the threat of extinction and the enforcement of trade bans have required bow makers to seek alternative woods. The hypothesis tested was that woods with physical, mechanical and acoustic properties similar to those of C. echinata would have high potential as alternative woods for bows. Accordingly, were investigated Handroanthus spp., Mezilaurus itauba, Hymenaea spp., Dipteryx spp., Diplotropis spp. and Astronium lecointei. Handroanthus and Diplotropis have the greatest number of similarities with C. echinata, but only Handroanthus spp. showed significant results in actual bow manufacture, suggesting the importance of such key properties as specific gravity, speed of sound propagation and modulus of elasticity. In practice, Handroanthus and Dipteryx produced bows of quality similar to that of C. echinata.

  3. Application of the Bow Tie method for evaluation of safety in the procedure of logging wells; Aplicacion del metodo de Bow Tie para la evaluacion de seguridad en la practica de perfilaje de pozos

    Energy Technology Data Exchange (ETDEWEB)

    Alfonso Pallares, C; Perez Reyes, Y.; Sarabia Molina, I.I. [Centro Nacional de Seguridad Nuclear (CNSN), La Habana (Cuba)

    2013-07-01

    This work consists of an assessment of security in the practice of logging of oil wells, using the method of Bow Tie for being a simple method of evaluation of the risk, which makes it possible in a structured way to set priorities to manage risk.

  4. Pulsar Wind Nebulae with Bow Shocks: Non-thermal Radiation and Cosmic Ray Leptons

    Science.gov (United States)

    Bykov, A. M.; Amato, E.; Petrov, A. E.; Krassilchtchikov, A. M.; Levenfish, K. P.

    2017-07-01

    Pulsars with high spin-down power produce relativistic winds radiating a non-negligible fraction of this power over the whole electromagnetic range from radio to gamma-rays in the pulsar wind nebulae (PWNe). The rest of the power is dissipated in the interactions of the PWNe with the ambient interstellar medium (ISM). Some of the PWNe are moving relative to the ambient ISM with supersonic speeds producing bow shocks. In this case, the ultrarelativistic particles accelerated at the termination surface of the pulsar wind may undergo reacceleration in the converging flow system formed by the plasma outflowing from the wind termination shock and the plasma inflowing from the bow shock. The presence of magnetic perturbations in the flow, produced by instabilities induced by the accelerated particles themselves, is essential for the process to work. A generic outcome of this type of reacceleration is the creation of particle distributions with very hard spectra, such as are indeed required to explain the observed spectra of synchrotron radiation with photon indices Γ≲ 1.5. The presence of this hard spectral component is specific to PWNe with bow shocks (BSPWNe). The accelerated particles, mainly electrons and positrons, may end up containing a substantial fraction of the shock ram pressure. In addition, for typical ISM and pulsar parameters, the e+ released by these systems in the Galaxy are numerous enough to contribute a substantial fraction of the positrons detected as cosmic ray (CR) particles above few tens of GeV and up to several hundred GeV. The escape of ultrarelativistic particles from a BSPWN—and hence, its appearance in the far-UV and X-ray bands—is determined by the relative directions of the interstellar magnetic field, the velocity of the astrosphere and the pulsar rotation axis. In this respect we review the observed appearance and multiwavelength spectra of three different types of BSPWNe: PSR J0437-4715, the Guitar and Lighthouse nebulae, and

  5. Implications of MODIS bow-tie distortion on aerosol optical depth retrievals, and techniques for mitigation

    Science.gov (United States)

    Sayer, A. M.; Hsu, N. C.; Bettenhausen, C.

    2015-12-01

    The scan geometry of the Moderate Resolution Imaging Spectroradiometer (MODIS) sensors, combined with the Earth's curvature, results in a pixel shape distortion known as the "bow-tie effect". Specifically, sensor pixels near the edge of the swath are elongated along-track and across-track compared to pixels near the centre of the swath, resulting in an increase of pixel area by up to a factor of ∼ 9 and, additionally, the overlap of pixels acquired from consecutive scans. The Deep Blue and Dark Target aerosol optical depth (AOD) retrieval algorithms aggregate sensor pixels and provide level 2 (L2) AOD at a nominal horizontal pixel size of 10 km, but the bow-tie distortion means that they also suffer from this size increase and overlap. This means that the spatial characteristics of the data vary as a function of satellite viewing zenith angle (VZA) and, for VZA > 30°, corresponding to approximately 50 % of the data, are areally enlarged by a factor of 50 % or more compared to this nominal pixel area and are not spatially independent of each other. This has implications for retrieval uncertainty and aggregated statistics, causing a narrowing of AOD distributions near the edge of the swath, as well as for data comparability from the application of similar algorithms to sensors without this level of bow-tie distortion. Additionally, the pixel overlap is not obvious to users of the L2 aerosol products because only pixel centres, not boundaries, are provided within the L2 products. A two-step procedure is proposed to mitigate the effects of this distortion on the MODIS aerosol products. The first (simple) step involves changing the order in which pixels are aggregated in L2 processing to reflect geographical location rather than scan order, which removes the bulk of the overlap between L2 pixels and slows the rate of growth of L2 pixel size vs. VZA. This can be achieved without significant changes to existing MODIS processing algorithms. The second step involves

  6. Is "Bow" for an Arrow or for Hair? A Classroom Demonstration on Gender Differences in Interpreting Ambiguous Information

    Science.gov (United States)

    Fa-Kaji, Naomi; Nguyen, Linda; Hebl, Mikki; Skorinko, Jeanine

    2016-01-01

    This article details a classroom demonstration of how gender differences in cognitive schemas can result in men and women differentially interpreting the same information. Students heard a series of six homonyms (e.g., bow and nail) spoken aloud and wrote down the first word with which they free-associated each homonym. When hearing the words…

  7. Effect of an isotropic outflow from the Galactic Centre on the bow-shock evolution along the orbit

    Czech Academy of Sciences Publication Activity Database

    Zajaček, Michal; Eckart, A.; Karas, Vladimír; Kunneriath, Devaky; Shahzamanian, B.; Sabha, N.; Muzic, K.; Valencia-S, M.

    2016-01-01

    Roč. 455, č. 2 (2016), s. 1257-1274 ISSN 0035-8711 R&D Projects: GA ČR(CZ) GC13-00070J Institutional research plan: CEZ:AV0Z1003909 Institutional support: RVO:67985815 Keywords : galactic centre * black hole * bow-shock Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.961, year: 2016

  8. A Prospective Evaluation of Duplex Ultrasound for Thoracic Outlet Syndrome in High-Performance Musicians Playing Bowed String Musicians

    Directory of Open Access Journals (Sweden)

    Garret Adam

    2018-01-01

    Full Text Available Thoracic outlet syndrome (TOS is a neurovascular condition involving the upper extremity, which is known to occur in individuals who perform chronic repetitive upper extremity activities. We prospectively evaluate the incidence of TOS in high-performance musicians who played bowed string musicians. Sixty-four high-performance string instrument musicians from orchestras and professional musical bands were included in the study. Fifty-two healthy volunteers formed an age-matched control group. Bilateral upper extremity duplex scanning for subclavian vessel compression was performed in all subjects. Provocative maneuvers including Elevated Arm Stress Test (EAST and Upper Limb Tension Test (ULTT were performed. Abnormal ultrasound finding is defined by greater than 50% subclavian vessel compression with arm abduction, diminished venous waveforms, or arterial photoplethysmography (PPG tracing with arm abduction. Bowed string instruments performed by musicians in our study included violin (41%, viola (33%, and cello (27%. Positive EAST or ULTT test in the musician group and control group were 44%, and 3%, respectively (p = 0.03. Abnormal ultrasound scan with vascular compression was detected in 69% of musicians, in contrast to 15% of control subjects (p = 0.03. TOS is a common phenomenon among high-performance bowed string instrumentalists. Musicians who perform bowed string instruments should be aware of this condition and its associated musculoskeletal symptoms.

  9. Atelier Bow-Wow on the Representation of Behaviorology: Yosiharu Tsukamoto in conversation with Anne Elisabeth Toft and Christina Capetillo

    DEFF Research Database (Denmark)

    Toft, Anne Elisabeth; Capetillo, Christina

    2015-01-01

    Yoshiharu Tsukamoto discussing the representational practices of Atelier Bow-Wow and its work on “Behaviorology”: How do you represent the seemingly un-representable? How do you depict and illustrate what is not tangible? How do you represent social practices, time-based processes, situations, sp...

  10. Bow-tie risk assessment combining causes and effects applied to gasoil storage in an abandoned salt cavern,

    NARCIS (Netherlands)

    Visser, K; Hendriks, D.; Wildenborg, T.; Duijne, H.

    2014-01-01

    A semi-quantitative risk assessment is presented for the storage of gas oil in depleted salt caverns in the Twente region, the Netherlands. It is based on a bow-tie model, in which an incident, leakage of gas oil from the storage system (cavern and wells), is evaluated by assessing its possible

  11. Nowcasting and forecasting of the magnetopause and bow shock—A status update

    Science.gov (United States)

    Petrinec, S. M.; Redmon, R. J.; Rastaetter, L.

    2017-01-01

    There has long been interest in knowing the shape and location of the Earth's magnetopause and of the standing fast-mode bow shock upstream of the Earth's magnetosphere. This quest for knowledge spans both the research and operations arenas. Pertinent to the latter, nowcasting and near-term forecasting are important for determining the extent to which the magnetosphere is compressed or expanded due to the influence of the solar wind bulk plasma and fields and the coupling to other magnetosphere-ionosphere processes with possible effects on assets. This article provides an update to a previous article on the same topic published 15 years earlier, with focus on studies that have been conducted, the current status of nowcasting and forecasting of geophysical boundaries, and future endeavors.

  12. Gyrating ions and large-amplitude monochromatic MHD waves upstream of the earth's bow shock

    Science.gov (United States)

    Thomsen, M. F.; Gosling, J. T.; Bame, S. J.; Rusell, C. T.

    1985-01-01

    Episodes of nearly monochromatic, low-frequency (0.03 Hz) hydromagnetic waves are occasionally observed upstream of the earth's bow shock. High time resolution (3 s) measurements of two-dimensional ion distributions during two nearly monochromatic wave events reveal that the ion distributions asociated with these waves are 'gyrating ions.' Such distributions consists of suprathermal ions with parallel and perpendicular velocities confined to a fairly narrow range of (nonzero) values. The ions are also often confined to a fairly narrow range of gyrophase angle ('gyrophase bunched'). In one of the two cases, the observed frequency of the waves agrees quite well with the Doppler shifted resonance frequency of waves in right-hand resonance with the observed gyrating ions. In the second case, the observed frequency is lower than the predicted frequency by a factor of 1.5-2.

  13. Short term memory bowing effect is consistent with presentation rate dependent decay.

    Science.gov (United States)

    Tarnow, Eugen

    2010-12-01

    I reanalyze the free recall data of Murdock, J Exp Psychol 64(5):482-488 (1962) and Murdock and Okada, J Verbal Learn and Verbal Behav 86:263-267 (1970) which show the famous bowing effect in which initial and recent items are recalled better than intermediate items (primacy and recency effects). Recent item recall probabilities follow a logarithmic decay with time of recall consistent with the tagging/retagging theory. The slope of the decay increases with increasing presentation rate. The initial items, with an effectively low presentation rate, decay with the slowest logarithmic slope, explaining the primacy effect. The finding that presentation rate limits the duration of short term memory suggests a basis for memory loss in busy adults, for the importance of slow music practice, for long term memory deficiencies for people with attention deficits who may be artificially increasing the presentation rates of their surroundings. A well-defined, quantitative measure of the primacy effect is introduced.

  14. On the proper Mach number and ratio of specific heats for modeling the Venus bow shock

    Science.gov (United States)

    Tatrallyay, M.; Russell, C. T.; Luhmann, J. G.; Barnes, A.; Mihalov, J. D.

    1984-01-01

    Observational data from the Pioneer Venus Orbiter are used to investigate the physical characteristics of the Venus bow shock, and to explore some general issues in the numerical simulation of collisionless shocks. It is found that since equations from gas-dynamic (GD) models of the Venus shock cannot in general replace MHD equations, it is not immediately obvious what the optimum way is to describe the desired MHD situation with a GD code. Test case analysis shows that for quasi-perpendicular shocks it is safest to use the magnetospheric Mach number as an input to the GD code. It is also shown that when comparing GD predicted temperatures with MHD predicted temperatures total energy should be compared since the magnetic energy density provides a significant fraction of the internal energy of the MHD fluid for typical solar wind parameters. Some conclusions are also offered on the properties of the terrestrial shock.

  15. Large amplitude MHD waves upstream of the Jovian bow shock: Reinterpretation

    Science.gov (United States)

    Goldstein, M. L.; Wong, H. K.; Vinas, A. F.; Smith, C. W.

    1984-01-01

    Observations of large amplitude magnetohydrodynamic (MHD) waves upstream of the Jovian bow shock were previously interpreted as arising from a resonant electromagnetic ion beam instability. That interpretation was based on the conclusion that the observed fluctuations were predominantly right elliptically polarized in the solar wind rest frame. Because it was noted that the fluctuations are, in fact, left elliptically polarized, a reanalysis of the observations was necessary. Several mechanisms for producing left hand polarized MHD waves in the observed frequency range were investigated. Instabilities excited by protons appear unlikely to account for the observations. A resonant instability excited by relativistic electrons escaping from the Jovian magnetosphere is a likely source of free energy consistent with the observations. Evidence for the existence of such a population of electrons was found in both the Low Energy Charged Particle experiments and Cosmic Ray experiments on Voyager 2.

  16. Large-amplitude MHD waves upstream of the Jovian bow shock Reinterpretation

    Science.gov (United States)

    Goldstein, M. L.; Wong, H. K.; Vinas, A. F.; Smith, C. W.

    1985-01-01

    Observations of large amplitude magnetohydrodynamic (MHD) waves upstream of the Jovian bow shock were previously interpreted as arising from a resonant electromagnetic ion beam instability. That interpretation was based on the conclusion that the observed fluctuations were predominantly right elliptically polarized in the solar wind rest frame. Because it was noted that the fluctuations are, in fact, left elliptically polarized, a reanalysis of the observations was necessary. Several mechanisms for producing left hand polarized MHD waves in the observed frequency range were investigated. Instabilities excited by protons appear unlikely to account for the observations. A resonant instability excited by relativistic electrons escaping from the Jovian magnetosphere is a likely source of free energy consistent with the observations. Evidence for the existence of such a population of electrons was found in both the Low Energy Charged Particle experiments and Cosmic Ray experiments on Voyager 2.

  17. A Multi-wavelength Study of an Isolated MSP Bow Shock

    Science.gov (United States)

    Romani, Roger W.; Slane, Patrick; Green, Andrew

    2017-08-01

    PSR J2124-3358 is the only single MSP known to sport an Halpha bow shock. This shock, now also seen in the UV, encloses an unusual X-ray pulsar wind nebula (PWN) with a long off-axis trail. Combining the X-ray and UV images with AAT/KOALA integral field spectroscopy of the Halpha emission, we have an unusually complete picture of the pulsar's (101 km/s transverse) motion and the latitudinal distribution of its wind flux. These images reveal the 3-D orientation of a hard-spectrum PWN jet and a softer equatorial outflow. Within the context of a thin shock model, we can constrain the total energy output of the pulsar and the neutron star moment of inertia. The IFU spectra show extreme Balmer dominance, which also constrains the nature of the UV shock emission.

  18. Recurrent juvenile ischemic stroke caused by bow hunter's stroke revealed by carotid duplex ultrasonography.

    Science.gov (United States)

    Takekawa, Hidehiro; Suzuki, Keisuke; Nishihira, Takahito; Iwasaki, Akio; Hoshiyama, Eisei; Okamura, Madoka; Numao, Ayaka; Suzuki, Shiho; Hirata, Koichi

    2015-07-01

    Bow hunter's stroke (BHS) is a rare cause of vertebrobasilar insufficiency due to rotational vertebral artery (VA) occlusion associated with head turning. We report a juvenile patient presenting with recurrent ischemic stroke caused by BHS, which was revealed by carotid duplex ultrasonography. Carotid duplex ultrasonography performed in the neutral position showed normal findings. However, disappearance of end-diastolic blood flow of contralateral VAs was observed with head rotation. Digital subtraction angiography confirmed occlusion at C1/2 levels in the VA contralateral to the head rotation, bilaterally. Importantly, our patient did not recognize the association of head rotation and previous episodes of stroke. We suggest that BHS should be considered in patients with cryptogenic stroke occurring in the vertebrobasilar artery territory.

  19. Phase ordering of zig-zag and bow-shaped hard needles in two dimensions.

    Science.gov (United States)

    Tavarone, Raffaele; Charbonneau, Patrick; Stark, Holger

    2015-09-21

    We perform extensive Monte Carlo simulations of a two-dimensional bent hard-needle model in both its chiral zig-zag and its achiral bow-shape configurations and present their phase diagrams. We find evidence for a variety of stable phases: isotropic, quasi-nematic, smectic-C, anti-ferromorphic smectic-A, and modulated-nematic. This last phase consists of layers formed by supramolecular arches. They create a modulation of the molecular polarity whose period is sensitively controlled by molecular geometry. We identify transition densities using correlation functions together with appropriately defined order parameters and compare them with predictions from Onsager theory. The contribution of the molecular excluded area to deviations from Onsager theory and simple liquid crystal phase morphology is discussed. We demonstrate the isotropic-quasi-nematic transition to be consistent with a Kosterlitz-Thouless disclination unbinding scenario.

  20. From Bows to Sound-Chests: Tracing the Ancestry of the Violin

    Directory of Open Access Journals (Sweden)

    Janelle R. Finley

    2016-04-01

    Full Text Available The ancestry of the violin is a subject that has been studied, researched, debated, and written about in great detail. However, despite all of the research and study, the ancestry of the violin is still not certain. This paper presents two schools of thought that propose different theories as to how the ancestry of the violin should be determined and what instruments should be included in the ancestry of the violin. The first school of thought proposes that the violin’s ancestry should be traced through the bow. The second theory proposes that the violin’s ancestry should be traced through the sound-chest of the violin. This paper also presents the different arguments for and against each theory, the importance of this topic, and the paper’s position on this topic. Research for this paper was accomplished through the use of scholarly books on the subject of the history of the violin.

  1. The effects of cervical headgear with an expanded inner bow in the permanent dentition.

    Science.gov (United States)

    Varlik, Selin Kale; Iscan, Hakan N

    2008-08-01

    In this study, the effects of cervical headgear (CHG) use on the transverse dimension of the maxillary dental arch were evaluated in patients in the permanent dentition. Thirteen girls and 12 boys (mean age: 13.41 +/- 0.52 years) with a bilateral full cusp Class II molar relationship comprised the study group. Fifteen girls and 10 boys with a Class I normal occlusion comprised the controls. In the treatment group, CHG with an expanded inner bow was used for a mean period of 11.2 +/- 5.6 months. The headgear was used for molar distalization and the force magnitude was 196.1 cN. After CHG treatment, the patients underwent non-extraction fixed orthodontic treatment for 14.1 +/- 2.5 months. During this period, the control group received regular dental check-ups. Dental casts obtained at the beginning (T1) and end (T2) of headgear use and at the end of orthodontic treatment (T3) and posteroanterior cephalograms taken at T1 and T2 were evaluated. A Student's t-test was used for intergroup comparison at T1, T2, and T3 and a Mann-Whitney U-test with a Bonferroni correction for comparison of treatment/observation changes. At T2, intercanine (0.96 +/- 0.56 mm), interpremolar (1.6 +/- 0.55 mm for the first premolar, 1.74 +/- 0.65 mm for the second premolar), and intermolar (2.31 +/- 0.75 mm) widths increased, while the distance between the intersection of the zygomatic process and the maxillary alveolar process on the right (JR) and left (JL) did not change. Fixed orthodontic treatment did not have any effect on any of the measurements. With the intentional expansion of the inner bow of CHG, the amount of maxillary dental arch expansion achieved in the permanent dentition was statistically significant (P < 0.017).

  2. Electron Scattering by High-Frequency Whistler Waves at Earth's Bow Shock

    Science.gov (United States)

    Oka, M.; Wilson, L. B., III; Phan, T. D.; Hull, A. J.; Amano, T.; Hoshino, M.; Argall, M. R.; Le Contel, O.; Agapitov, O.; Gersham, D. J.; hide

    2017-01-01

    Electrons are accelerated to non-thermal energies at shocks in space and astrophysical environments. While different mechanisms of electron acceleration have been proposed, it remains unclear how non-thermal electrons are produced out of the thermal plasma pool. Here, we report in situ evidence of pitch-angle scattering of non-thermal electrons by whistler waves at Earths bow shock. On 2015 November 4, the Magnetospheric Multiscale (MMS) mission crossed the bow shock with an Alfvn Mach number is approximately 11 and a shock angle of approximately 84deg. In the ramp and overshoot regions, MMS revealed bursty enhancements of non-thermal (0.52 keV) electron flux, correlated with high-frequency (0.2 - 0.4 Omega(sub ce), where Omega(sub ce) is the cyclotron frequency) parallel-propagating whistler waves. The electron velocity distribution (measured at 30 ms cadence) showed an enhanced gradient of phase-space density at and around the region where the electron velocity component parallel to the magnetic field matched the resonant energy inferred from the wave frequency range. The flux of 0.5 keV electrons (measured at 1ms cadence) showed fluctuations with the same frequency. These features indicate that non-thermal electrons were pitch-angle scattered by cyclotron resonance with the high-frequency whistler waves. However, the precise role of the pitch-angle scattering by the higher-frequency whistler waves and possible nonlinear effects in the electron acceleration process remains unclear.

  3. Electron Scattering by High-frequency Whistler Waves at Earth’s Bow Shock

    Science.gov (United States)

    Oka, M.; Wilson, L. B., III; Phan, T. D.; Hull, A. J.; Amano, T.; Hoshino, M.; Argall, M. R.; Le Contel, O.; Agapitov, O.; Gershman, D. J.; Khotyaintsev, Y. V.; Burch, J. L.; Torbert, R. B.; Pollock, C.; Dorelli, J. C.; Giles, B. L.; Moore, T. E.; Saito, Y.; Avanov, L. A.; Paterson, W.; Ergun, R. E.; Strangeway, R. J.; Russell, C. T.; Lindqvist, P. A.

    2017-06-01

    Electrons are accelerated to non-thermal energies at shocks in space and astrophysical environments. While different mechanisms of electron acceleration have been proposed, it remains unclear how non-thermal electrons are produced out of the thermal plasma pool. Here, we report in situ evidence of pitch-angle scattering of non-thermal electrons by whistler waves at Earth’s bow shock. On 2015 November 4, the Magnetospheric Multiscale (MMS) mission crossed the bow shock with an Alfvén Mach number ˜11 and a shock angle ˜84°. In the ramp and overshoot regions, MMS revealed bursty enhancements of non-thermal (0.5-2 keV) electron flux, correlated with high-frequency (0.2-0.4 {{{Ω }}}{ce}, where {{{Ω }}}{ce} is the cyclotron frequency) parallel-propagating whistler waves. The electron velocity distribution (measured at 30 ms cadence) showed an enhanced gradient of phase-space density at and around the region where the electron velocity component parallel to the magnetic field matched the resonant energy inferred from the wave frequency range. The flux of 0.5 keV electrons (measured at 1 ms cadence) showed fluctuations with the same frequency. These features indicate that non-thermal electrons were pitch-angle scattered by cyclotron resonance with the high-frequency whistler waves. However, the precise role of the pitch-angle scattering by the higher-frequency whistler waves and possible nonlinear effects in the electron acceleration process remains unclear.

  4. Injection and acceleration of H+ and He2+ at Earth's bow shock

    Directory of Open Access Journals (Sweden)

    M. Scholer

    1999-05-01

    Full Text Available We have performed a number of one-dimensional hybrid simulations (particle ions, massless electron fluid of quasi-parallel collisionless shocks in order to investigate the injection and subsequent acceleration of part of the solar wind ions at the Earth's bow shock. The shocks propagate into a medium containing magnetic fluctuations, which are initially superimposed on the background field, as well as generated or enhanced by the electromagnetic ion/ion beam instability between the solar wind and backstreaming ions. In order to study the mass (M and charge (Q dependence of the acceleration process He2+ is included self-consistently. The upstream differential intensity spectra of H+ and He2+ can be well represented by exponentials in energy. The e-folding energy Ec is a function of time: Ec increases with time. Furthermore the e-folding energy (normalized to the shock ramming energy Ep increases with increasing Alfvén Mach number of the shock and with increasing fluctuation level of the initially superimposed turbulence. When backstreaming ions leave the shock after their first encounter they exhibit already a spectrum which extends to more than ten times the shock ramming energy and which is ordered in energy per charge. From the injection spectrum it is concluded that leakage of heated downstream particles does not contribute to ion injection. Acceleration models that permit thermal particles to scatter like the non-thermal population do not describe the correct physics.Key words. Interplanetary physics (planetary bow shocks · Space plasma physics (charged particle motion and acceleration; numerical simulation studies

  5. Automated bow shock and radiation belt edge identification methods and their application for Cluster, THEMIS/ARTEMIS and Van Allen Probes data

    Science.gov (United States)

    Facsko, Gabor; Sibeck, David; Balogh, Tamas; Kis, Arpad; Wesztergom, Viktor

    2017-04-01

    The bow shock and the outer rim of the outer radiation belt are detected automatically by our algorithm developed as a part of the Boundary Layer Identification Code Cluster Active Archive project. The radiation belt positions are determined from energized electron measurements working properly onboard all Cluster spacecraft. For bow shock identification we use magnetometer data and, when available, ion plasma instrument data. In addition, electrostatic wave instrument electron density, spacecraft potential measurements and wake indicator auxiliary data are also used so the events can be identified by all Cluster probes in highly redundant way, as the magnetometer and these instruments are still operational in all spacecraft. The capability and performance of the bow shock identification algorithm were tested using known bow shock crossing determined manually from January 29, 2002 to February 3,. The verification enabled 70% of the bow shock crossings to be identified automatically. The method shows high flexibility and it can be applied to observations from various spacecraft. Now these tools have been applied to Time History of Events and Macroscale Interactions during Substorms (THEMIS)/Acceleration, Reconnection, Turbulence, and Electrodynamics of the Moon's Interaction with the Sun (ARTEMIS) magnetic field, plasma and spacecraft potential observations to identify bow shock crossings; and to Van Allen Probes supra-thermal electron observations to identify the edges of the radiation belt. The outcomes of the algorithms are checked manually and the parameters used to search for bow shock identification are refined.

  6. Bowing and expansion of natural stone panels: marble and limestone testing and assessment

    Directory of Open Access Journals (Sweden)

    Grelk, Bent

    2008-06-01

    Full Text Available Natural stone has been used as a building material for centuries. In the past, load bearing members were made of entirely of stone, but in the last 50 years new processing techniques have made the production and use of thin facade cladding a profitable venture. Unfortunately however, marble facades on buildings in Europe and elsewhere have undergone severe deterioration. The EC-financed TEAM project (2000-2005 studied the bowing observed on marble facades in both cold and warm climates. TEAM’s main objectives were to understand and explain the expansion, bowing, and strength loss mechanisms governing the decay of marble- and limestone-clad facades, and to draft new European standards to prevent the use of marble and limestone poorly suited to outdoor cladding. A survey of some 200 buildings afforded a clear picture of the geographical, geological and climatic scope of the problem. Detailed case studies of six buildings resulted in a facade assessment methodology that included a monitoring system and risk assessment. Both laboratory and field research was conducted on almost 100 different types of stone from different countries and in place in different climates. The outcome was the determination of the decay mechanisms and critical factors. Two test methods and respective precision statements, one for bowing and the other for irreversible thermal expansion in high humidity conditions, were prepared for submission to CEN TC 246.La piedra natural se ha empleado como material de construcción durante siglos. En el pasado, se solía utilizar en elementos de carga, pero en los últimos 50 años las nuevas técnicas de procesamiento han permitido que sea comercialmente rentable producir y utilizar revestimientos para fachadas de espesor reducido. Desafortunadamente, numerosas fachadas de mármol de edificios tanto en Europa como fuera de ella han sufrido graves problemas derivados del deterioro de la piedra. El proyecto TEAM (2000

  7. Two-Polarisation Physical Model of Bowed Strings with Nonlinear Contact and Friction Forces, and Application to Gesture-Based Sound Synthesis

    Directory of Open Access Journals (Sweden)

    Charlotte Desvages

    2016-05-01

    Full Text Available Recent bowed string sound synthesis has relied on physical modelling techniques; the achievable realism and flexibility of gestural control are appealing, and the heavier computational cost becomes less significant as technology improves. A bowed string sound synthesis algorithm is designed, by simulating two-polarisation string motion, discretising the partial differential equations governing the string’s behaviour with the finite difference method. A globally energy balanced scheme is used, as a guarantee of numerical stability under highly nonlinear conditions. In one polarisation, a nonlinear contact model is used for the normal forces exerted by the dynamic bow hair, left hand fingers, and fingerboard. In the other polarisation, a force-velocity friction curve is used for the resulting tangential forces. The scheme update requires the solution of two nonlinear vector equations. The dynamic input parameters allow for simulating a wide range of gestures; some typical bow and left hand gestures are presented, along with synthetic sound and video demonstrations.

  8. Non-stationarity of the quasi-perpendicular bow shock: comparison between Cluster observations and simulations

    Directory of Open Access Journals (Sweden)

    H. Comişel

    2011-02-01

    Full Text Available We have performed full particle electromagnetic simulations of a quasi-perpendicular shock. The shock parameters have been chosen to be appropriate for the quasi-perpendicular Earth's bow shock observed by Cluster on 24 January 2001 (Lobzin et al., 2007. We have performed two simulations with different ion to electron mass ratio: run 1 with mi/me=1840 and run 2 with mi/me=100. In run 1 the growth rate of the modified two-stream instability (MTSI is large enough to get excited during the reflection and upstream gyration of part of the incident solar wind ions. The waves due to the MTSI are on the whistler mode branch and have downstream directed phase velocities in the shock frame. The Poynting flux (and wave group velocity far upstream in the foot is also directed in the downstream direction. However, in the density and magnetic field compression region of the overshoot the waves are refracted and the Poynting flux in the shock frame is directed upstream. The MTSI is suppressed in the low mass ratio run 2. The low mass ratio run shows more clearly the non-stationarity of the shock with a larger time scale of the order of an inverse ion gyrofrequency (Ωci: the magnetic field profile flattens and steepens with a period of ~1.5Ωci−1. This non-stationarity is different from reformation seen in previous simulations of perpendicular or quasi-perpendicular shocks. Beginning with a sharp shock ramp the large electric field in the normal direction leads to high reflection rate of solar wind protons. As they propagate upstream, the ion bulk velocity decreases and the magnetic field increases in the foot, which results in a flattening of the magnetic field profile and in a decrease of the normal electric field. Subsequently the reflection rate decreases and the whole shock profile steepens again. Superimposed on this 'breathing' behavior are in the realistic mass ratio case the waves due to the MTSI. The simulations lead us to a re-interpretation of

  9. Dispersion of low frequency plasma waves upstream of the quasi-perpendicular terrestrial bow shock

    Directory of Open Access Journals (Sweden)

    A. P. Dimmock

    2013-08-01

    Full Text Available Low frequency waves in the foot of a supercritical quasi-perpendicular shock front have been observed since the very early in situ observations of the terrestrial bow shock (Guha et al., 1972. The great attention that has been devoted to these type of waves since the first observations is explained by the key role attributed to them in the processes of energy redistribution in the shock front by various theoretical models. In some models, these waves play the role of the intermediator between the ions and electrons. It is assumed that they are generated by plasma instability that exist due to the counter-streaming flows of incident and reflected ions. In the second type of models, these waves result from the evolution of the shock front itself in the quasi-periodic process of steepening and overturning of the magnetic ramp. However, the range of the observed frequencies in the spacecraft frame are not enough to distinguish the origin of the observed waves. It also requires the determination of the wave vectors and the plasma frame frequencies. Multipoint measurements within the wave coherence length are needed for an ambiguous determination of the wave vectors. In the main multi-point missions such as ISEE, AMPTE, Cluster and THEMIS, the spacecraft separation is too large for such a wave vector determination and therefore only very few case studies are published (mainly for AMPTE UKS AMPTE IRM pair. Here we present the observations of upstream low frequency waves by the Cluster spacecraft which took place on 19 February 2002. The spacecraft separation during the crossing of the bow shock was small enough to determine the wave vectors and allowed the identification of the plasma wave dispersion relation for the observed waves. Presented results are compared with whistler wave dispersion and it is shown that contrary to previous studies based on the AMPTE data, the phase velocity in the shock frame is directed downstream. The consequences of this

  10. Study on the effect of the CANFLEX-NU fuel element bowing on the critical heat flux

    Energy Technology Data Exchange (ETDEWEB)

    Suk, Ho Chun; Cho, Moon Sung; Jeon, Ji Su

    2001-01-01

    The effect of the CANFLEX-NU fuel element bowing on the critical heat flux is reviewed and analyzed, which is requested by KINS as the Government design licensing condition for the use of the fuel bundles in CANDU power reactors. The effect of the gap between two adjacent fuel elements on the critical heat flux and onset-of-dryout power is studied. The reduction of the width of a single inter-rod gap from its nominal size to the minimum manufacture allowance of 1 mm has a negligible effects on the thermal-hydraulic performance of the bundle for the given set of boundary conditions applied to the CANFLEX-43 element bundle in an uncrept channel. As expected, the in-reactor irradiation test results show that there are no evidence of the element bow problems on the bundle performance.

  11. The effect of element bow on dryout power and post-dryout heat transfer in CANDU fuel bundles

    Energy Technology Data Exchange (ETDEWEB)

    Sutradhar, S.C.; Schenk, J.R. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

    1997-07-01

    Dryout and post-dryout tests were performed in a modified 37-element simulated CANDU fuel bundle, with one outer element of the last bundle bowed at gradual but controlled steps toward the pressure-tube wall. The dryout power decreased moderately as the gap size was reduced from nominal to about 40%. For smaller-than-40%-gap sizes, however, the dryout power increased in most cases; this resulted in almost equal dryout powers at the nominal and zero gap sizes. The maximum surface temperature of the bowed element at up to 20% overpower increased with decreasing gap sizes; however, for gap sizes smaller than 35% of the nominal gap, the surface temperature fluctuated moderately. (author)

  12. Pattern Switchable Antenna System Using Inkjet-Printed Directional Bow-Tie for Bi-Direction Sensing Applications.

    Science.gov (United States)

    Eom, Seung-Hyun; Seo, Yunsik; Lim, Sungjoon

    2015-12-10

    In this paper, we propose a paper-based pattern switchable antenna system using inkjet-printing technology for bi-direction sensor applications. The proposed antenna system is composed of two directional bow-tie antennas and a switching network. The switching network consists of a single-pole-double-throw (SPDT) switch and a balun element. A double-sided parallel-strip line (DSPSL) is employed to convert the unbalanced microstrip mode to the balanced strip mode. Two directional bow-tie antennas have different radiation patterns because of the different orientation of the reflectors and antennas. It is demonstrated from electromagnetic (EM) simulation and measurement that the radiation patterns of the proposed antenna are successfully switched by the SPDT switch.

  13. A methodology to select a group of species among 131 tropical (colombian) species for bowed timber applications

    OpenAIRE

    Caicedo-Llano,Natalia

    2014-01-01

    We present a methodology of selecting wood species for architectural purposes, especially when a curved shape is required. First, a mechanical criterion is associated with a morphology, more specifically a characteristic value of stress-strain relation is associated with the attitude of wood for bowing. Second, a filtering is done using data of wood in the green state and in the dry state, and then the wood selection is refined by using relevant criteria related to environment and economic co...

  14. Kaguya observations of the lunar wake in the terrestrial foreshock: Surface potential change by bow-shock reflected ions

    Science.gov (United States)

    Nishino, Masaki N.; Harada, Yuki; Saito, Yoshifumi; Tsunakawa, Hideo; Takahashi, Futoshi; Yokota, Shoichiro; Matsushima, Masaki; Shibuya, Hidetoshi; Shimizu, Hisayoshi

    2017-09-01

    There forms a tenuous region called the wake behind the Moon in the solar wind, and plasma entry/refilling into the wake is a fundamental problem of the lunar plasma science. High-energy ions and electrons in the foreshock of the Earth's magnetosphere were detected at the lunar surface in the Apollo era, but their effects on the lunar night-side environment have never been studied. Here we show the first observation of bow-shock reflected protons by Kaguya (SELENE) spacecraft in orbit around the Moon, confirming that solar wind plasma reflected at the terrestrial bow shock can easily access the deepest lunar wake when the Moon stays in the foreshock (We name this mechanism 'type-3 entry'). In a continuous type-3 event, low-energy electron beams from the lunar night-side surface are not obvious even though the spacecraft location is magnetically connected to the lunar surface. On the other hand, in an intermittent type-3 entry event, the kinetic energy of upward-going field-aligned electron beams decreases from ∼ 80 eV to ∼ 20 eV or electron beams disappear as the bow-shock reflected ions come accompanied by enhanced downward electrons. According to theoretical treatment based on electric current balance at the lunar surface including secondary electron emission by incident electron and ion impact, we deduce that incident ions would be accompanied by a few to several times higher flux of an incident electron flux, which well fits observed downward fluxes. We conclude that impact by the bow-shock reflected ions and electrons raises the electrostatic potential of the lunar night-side surface.

  15. Assessing the potential for rainbow trout reproduction in tributaries of the Mountain Fork River below Broken Bow Dam, southeastern Oklahoma

    Science.gov (United States)

    Long, James M.; Starks, Trevor A.; Farling, Tyler; Bastarache, Robert

    2016-01-01

    Stocked trout (Salmonidae) in reservoir tailwater systems in the Southern United States have been shown to use tributary streams for spawning and rearing. The lower Mountain Fork of the Little River below Broken Bow Dam is one of two year-round tailwater trout fisheries in Oklahoma, and the only one with evidence of reproduction by stocked rainbow trout (Oncorhynchus mykiss). Whether stocked trout use tributaries in this system for spawning is unknown. Furthermore, an

  16. Perspectives on grizzly bear management in Banff National Park and the Bow River Watershed, Alberta: A Q methodology study

    OpenAIRE

    Chamberlain, Emily Carter

    2006-01-01

    Conserving populations of large carnivores such as grizzly bears (Ursus arctos) requires not only biophysical research, but also an understanding of the values and beliefs of the people involved with and affected by carnivore management. I used Q methodology to examine views of stakeholders concerning grizzly bear management in the Banff-Bow Valley region of Alberta, Canada. In recent years, decision-making about bears in this region has been characterized by acrimonious disputes over scienti...

  17. Traction bow for acute reduction of fracture and/or dislocation of the thoracic or thoracolumbar spine.

    Science.gov (United States)

    Wang, G J; Eschenroeder, H C; Redler, M R; Stamp, W G

    1988-01-01

    Treatment of acute fractures and/or fracture dislocations of the thoracic or thoracolumbar spine has traditionally involved bedrest or the use of traction devices with external hanging weights, until surgical correction can be accomplished. A fiberglass tubular traction bow with continuous adjustable elastic tension has been designed for the application of skeletal traction. When used to treat thoracic or thoracolumbar fractures and/or dislocations, it can maintain distraction forces in an uninterrupted fashion. Ten patients with acute fractures and/or dislocations of the thoracic or thoracolumbar spine were treated with this traction bow. All of the spinal deformities showed dramatic improvement within the first 3 h of treatment. The patients all showed immediate lessening of acute severe pain, and those with incomplete neurologic loss showed improvement of their neurologic function. The patients all tolerated the device well and were able to undergo radiologic examination and, ultimately, spinal fusion while they were stabilized in the traction bow. We believe this device is especially valuable for immediate reduction of spine and care of patients with fractures or fracture dislocations of the thoracolumbar spine.

  18. Modified tandem traction bow appliance compared with facemask therapy in treating Class III malocclusions.

    Science.gov (United States)

    Tortop, Tuba; Kaygisiz, Emine; Gencer, Deniz; Yuksel, Sema; Atalay, Zeynep

    2014-07-01

    To compare the effects of the modified tandem traction bow appliance (MTTBA) and the facemask in treating patients with Class III malocclusion. The material consisted of the pre-post treatment\\pre-post observation lateral cephalograms of 65 subjects with skeletal and dental Class III malocclusion. In the first group 21 patients (mean age: 10 years, 6 months) were treated with a Delaire-type facemask (FM). In the second group 22 patients treated (mean age: 10 years) with MTTBA. The remaining 22 children (mean age: 9 years, 7 months) were observed without treatment for 11 months. Increase in SNA, N-FH ⊥ A, and ANB angles were significantly greater in the treatment groups compared to the control group. However, ANB angle showed a significantly greater increase in the FM group (2.8 ± 0.30°) than in the MTTBA group (2.0 ± 0.18°). The overjet and molar relation increased significantly in both treatment groups, but in the FM group (5.2 ± 0.40 mm) increase in overjet was significantly greater than in the MTTBA group (4.0 ± 0.27 mm). Mesial movement of upper molar and incisor were found to be greater in the FM group compared to the modified TTBA group. Both appliances were found to be effective in the treatment of Class III malocclusion. Their skeletal and dental effects showed differences due to their design.

  19. Computational fluid dynamics based bulbous bow optimization using a genetic algorithm

    Science.gov (United States)

    Mahmood, Shahid; Huang, Debo

    2012-09-01

    Computational fluid dynamics (CFD) plays a major role in predicting the flow behavior of a ship. With the development of fast computers and robust CFD software, CFD has become an important tool for designers and engineers in the ship industry. In this paper, the hull form of a ship was optimized for total resistance using CFD as a calculation tool and a genetic algorithm as an optimization tool. CFD based optimization consists of major steps involving automatic generation of geometry based on design parameters, automatic generation of mesh, automatic analysis of fluid flow to calculate the required objective/cost function, and finally an optimization tool to evaluate the cost for optimization. In this paper, integration of a genetic algorithm program, written in MATLAB, was carried out with the geometry and meshing software GAMBIT and CFD analysis software FLUENT. Different geometries of additive bulbous bow were incorporated in the original hull based on design parameters. These design variables were optimized to achieve a minimum cost function of "total resistance". Integration of a genetic algorithm with CFD tools proves to be effective for hull form optimization.

  20. Postural stability, clicker reaction time and bow draw force predict performance in elite recurve archery.

    Science.gov (United States)

    Spratford, Wayne; Campbell, Rhiannon

    2017-06-01

    Recurve archery is an Olympic sport that requires extreme precision, upper body strength and endurance. The purpose of this research was to quantify how postural stability variables both pre- and post-arrow release, draw force, flight time, arrow length and clicker reaction time, collectively, impacted on the performance or scoring outcomes in elite recurve archery athletes. Thirty-nine elite-level recurve archers (23 male and 16 female; mean age = 24.7 ± 7.3 years) from four different countries volunteered to participate in this study prior to competing at a World Cup event. An AMTI force platform (1000Hz) was used to obtain centre of pressure (COP) measurements 1s prior to arrow release and 0.5s post-arrow release. High-speed footage (200Hz) allowed for calculation of arrow flight time and score. Results identified clicker reaction time, draw force and maximum sway speed as the variables that best predicted shot performance. Specifically, reduced clicker reaction time, greater bow draw force and reduced postural sway speed post-arrow release were predictors of higher scoring shots. It is suggested that future research should focus on investigating shoulder muscle tremors at full draw in relation to clicker reaction time, and the effect of upper body strength interventions (specifically targeting the musculature around the shoulder girdle) on performance in recurve archers.

  1. Relativistic Electrons Produced by Foreshock Disturbances Observed Upstream of Earth's Bow Shock

    Science.gov (United States)

    Wilson, L. B., III; Sibeck, D. G.; Turner, D. L.; Osmane, A.; Caprioli, D.; Angelopoulos, V.

    2016-01-01

    Charged particles can be reflected and accelerated by strong (i.e., high Mach number) astrophysical collisionless shock waves, streaming away to form a foreshock region in communication with the shock. Foreshocks are primarily populated by suprathermal ions that can generate foreshock disturbances-largescale (i.e., tens to thousands of thermal ion Larmor radii), transient (approximately 5-10 per day) structures. They have recently been found to accelerate ions to energies of several keV. Although electrons in Saturn's high Mach number (M > 40) bow shock can be accelerated to relativistic energies (nearly 1000 keV), it has hitherto been thought impossible to accelerate electrons beyond a few tens of keV at Earth's low Mach number (1 =M shock. Here we report observations of electrons energized by foreshock disturbances to energies up to at least approximately 300 keV. Although such energetic electrons have been previously observed, their presence has been attributed to escaping magnetospheric particles or solar events. These relativistic electrons are not associated with any solar or magnetospheric activity. Further, due to their relatively small Larmor radii (compared to magnetic gradient scale lengths) and large thermal speeds (compared to shock speeds), no known shock acceleration mechanism can energize thermal electrons up to relativistic energies. The discovery of relativistic electrons associated with foreshock structures commonly generated in astrophysical shocks could provide a new paradigm for electron injections and acceleration in collisionless plasmas.

  2. CFD analyses of the rod bowing effect on the subchannel outlet temperature distribution

    Energy Technology Data Exchange (ETDEWEB)

    Ekstroem, Karoliina; Toppila, Timo [Fortum Power and Heat, Fortum (Finland)

    2017-09-15

    In the Loviisa 1 and 2 nuclear power plants the subcooling margin of the hottest subchannel of the fuel assembly is monitored. The temperature of the coolant in the hottest subchannel is limited to the constant saturation temperature. Bending of the fuel rods occurs during normal operation due to the differences in the heat profiles of the rods. The coolant temperature will rise more in the subchannel with smaller flow area due to the bending and this has to be taken into account in the safety margin of subchannel enthalpy rise. Computational Fluid Dynamics (CFD) simulations are used to estimate how much the estimated maximum bow of a rod affects the temperature rise of the subchannel. The quantitative uncertainty of the predicted enthalpy rise in fuel bundle subchannel is estimated based on the uncertainty of modelling of mixing between subchannels. The measured turbulence quantities from LDA measurements of cold test assembly made in 1990s in Fortum are compared with CFD results to give uncertainty estimation for turbulence, which is further used for uncertainty estimation of mixing and simulated subchannel enthalpy rise.

  3. ANALISA PENGARUH BENTUK LAMBUNG AXE BOW PADA KAPAL HIGH SPEED CRAFT TERHADAP HAMBATAN TOTAL

    Directory of Open Access Journals (Sweden)

    Romadhoni Oni

    2015-06-01

    Full Text Available Hambatan merupakan salah satu faktor utama yang mempengaruhi proses perancangan sebuah kapal. Kapal dengan bentuk lambung yang baik akan menghasilkan hambatan yang efisiensi sehingga operasional kapal dan pergerakan kapal lebih baik. Pada ini penelitian dilakukan dengan memodelkan kapal high speed craft tipe Crew boat panjang 38 meter, lebar 7.6 meter, tinggi 3.65 meter dan draft 1.89 meter. Selanjutnya diselidiki model lambung kapal yang menghasilkan hambatan total paling kecil menggunakan pendekatan studi numerik software (maxsuft hullspeed metode savitsky dan holtrop dan software Computational Fluid Dynamics (CFD. Hasil penelitian berdasarkan analisa numerik (Maxsuft –Hullspeed dan CFD menujukkan pada kecepatan sevice bentuk lambung model AXE Bow memiliki nilai hambatan yang lebih kecil dibandingkan model kapal planing hull chine (HPC dan rounded hull (RH. Hasil perhitungan numerik dan CFD memiliki nilai yang hampir sama pada setiap variasi model. Hasil komparisi yang dilakukan didapatkan selisih total hambatan pada kecepatan 25 knot yaitu  model HPC 1.8 kN, model HPCAB 5.2 kN, model RH 4.8 kN dan model 5.1 kN. Dari perbandingan kedua metode tersebut memiliki selisih cukup kecil yaitu  kurang dari 5%. Selain mendapatkan nilai hambatan Software CFD akan menghasilkan nilai  perbandingan gaya angkat (lift force, dan total pressure yang terdistribusi  pada permukaan model setiap variasi kecepatan.

  4. Relativistic Electrons Produced by Foreshock Disturbances Observed Upstream of Earth's Bow Shock

    Science.gov (United States)

    Wilson, L. B., III; Sibeck, D. G.; Turner, D. L.; Osmane, A.; Caprioli, D.; Angelopoulos, V.

    2016-01-01

    Charged particles can be reflected and accelerated by strong (i.e., high Mach number) astrophysical collisionless shock waves, streaming away to form a foreshock region in communication with the shock. Foreshocks are primarily populated by suprathermal ions that can generate foreshock disturbances-largescale (i.e., tens to thousands of thermal ion Larmor radii), transient (approximately 5-10 per day) structures. They have recently been found to accelerate ions to energies of several keV. Although electrons in Saturn's high Mach number (M > 40) bow shock can be accelerated to relativistic energies (nearly 1000 keV), it has hitherto been thought impossible to accelerate electrons beyond a few tens of keV at Earth's low Mach number (1 =M electrons energized by foreshock disturbances to energies up to at least approximately 300 keV. Although such energetic electrons have been previously observed, their presence has been attributed to escaping magnetospheric particles or solar events. These relativistic electrons are not associated with any solar or magnetospheric activity. Further, due to their relatively small Larmor radii (compared to magnetic gradient scale lengths) and large thermal speeds (compared to shock speeds), no known shock acceleration mechanism can energize thermal electrons up to relativistic energies. The discovery of relativistic electrons associated with foreshock structures commonly generated in astrophysical shocks could provide a new paradigm for electron injections and acceleration in collisionless plasmas.

  5. Theory of 2{omega}{sub pe} radiation induced by the bow shock

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, P.H.; Wu, C.S. [Univ. of Maryland, College Park, MD (United States); Vinas, A.F.; Reiner, M.J.; Fainberg, J.; Stone, R.G. [NASA Goddard Space Flight Center, Greenbelt, MD (United States)

    1994-12-01

    A new radiation emission mechanism is proposed to explain electromagnetic radiation observed at twice the electron plasma frequency, 2{omega}{sub pe} in the upstream region of the Earth`s bow shock. This radiation has its origin at the electron foreshock boundary where energetic electron beams and intense narrow-band Langmuir waves are observed. The proposed emission mechanism results from the interaction of the electron beam and Langmuir waves that are backscattered off thermal ions. This interaction is described by a nonlinear dispersion equation which incorporates an effect owing to electron trajectory modulation by the backscattered Langmuir waves. Subsequent analysis of the dispersion equation reveals two important consequences. First, a long-wavelength electrostatic quasi-mode with frequency at 2{omega}{sup pe} is excited, and second, the quasi-mode and the electromagnetic mode are nonlinearly coupled. The implication is that, when the excited 2{omega}{sub pe} quasi-mode propagates in an inhomogeneous medium with slightly decreasing density, the quasi-mode can be converted directly into an electromagnetic mode. Hence the eletromagnetic radiation at twice the plasma frequency is generated. Numerical solutions of the dispersion equation with the choice of parameters that describe physical characteristics of the electron foreshock are presented, which illustrates the viability of the new mechanism. 24 refs., 2 figs.

  6. Theory of 2 omega(sub pe) radiation induced by the bow shock

    Science.gov (United States)

    Yoon, Peter H.; Wu, C. S.; Vinas, A. F.-; Reiner, M. J.; Fainberg, J.; Stone, R. G.

    1994-01-01

    A new radiation emission mechanism is proposed to explain electomagnetic radiation observed at twice the electron plasma frequency, 2 omega(sub pe), in the upstream region of the Earth's bow shock. This radiation had its origin at the electron foreshock boundary where energetic electron beams and intense narrow-band Langmiur waves are observed. The proposed emission mechanism results from the interaction of the electron beam and Langmuir waves that are backscattered off thermal ions. This interaction is described by a nonlinear dispersion equation which incorporates an effect owing to electron trajectory modulation by the backscattered Langmuir waves. Subsequent analysis of the dispersion equation reveals two important consequences. First, a long-wavelength electrostatic quasi-mode with frequency at 2 omega(sub pe) is excited, and second, the quasi-mode and the electomagnetic mode are nonlinearly coupled. The implication is that, when the excited 2 omega(sub pe) quasi-mode propagates in an inhomgeneous medium with slightly decreasing density, the quasi-mode can be converted directly into an electromagnetic mode. Hense the electomagnetic radiation at twice the plasma frequency is generated. Numerical solutions of the dispersion equation with the choice of parameters that describe physical characteristics of the electron foreshock are presented, which illustrates the viability of the new mechanism.

  7. The Parametric Study and Fine-Tuning of Bow-Tie Slot Antenna with Loaded Stub.

    Science.gov (United States)

    Shafiei, M M; Moghavvemi, Mahmoud; Wan Mahadi, Wan Nor Liza

    2017-01-01

    A printed Bow-Tie slot antenna with loaded stub is proposed and the effects of changing the dimensions of the slot area, the stub and load sizes are considered in this paper. These parameters have a considerable effect on the antenna characteristics as well as its performance. An in-depth parametric study of these dimensions is presented. This paper proposes the necessary conditions for initial approximation of dimensions needed to design this antenna. In order to achieve the desired performance of the antenna fine tuning of all sizes of these parameters is required. The parametric studies used in this paper provide proper trends for initiation and tuning the design. A prototype of the antenna for 1.7GHz to 2.6GHz band is fabricated. Measurements conducted verify that the designed antenna has wideband characteristics with 50% bandwidth around the center frequency of 2.1GHz. Conducted measurements for reflection coefficient (S11) and radiation pattern also validate our simulation results.

  8. Experimental demonstration of bow-shock instability and its numerical analysis

    Science.gov (United States)

    Kikuchi, Y.; Ohnishi, N.; Ohtani, K.

    2017-05-01

    An experimental demonstration was carried out in a ballistic range at high Mach numbers with the low specific heat ratio gas hydrofluorocarbon HFC-134a to observe the unstable bow-shock wave generated in front of supersonic blunt objects. The shadowgraph images obtained from the experiments showed instability characteristics, in which the disturbances grow and flow downstream and the wake flow appears wavy because of the shock oscillation. Moreover, the influence of the body shape and specific heat ratio on the instability was investigated for various experimental conditions. Furthermore, the observed features, such as wave structure and disturbance amplitude, were captured by numerical simulations, and it was demonstrated that computational fluid dynamics could effectively simulate the physical instability. In addition, it was deduced that the shock instability is induced by sound emissions from the edge of the object. This inference supports the dependence of the instability on the specific heat ratio and Mach number because the shock stand-off distance is affected by these parameters and limits the sound wave propagation.

  9. Bow hull-form optimization in waves of a 66,000 DWT bulk carrier

    Directory of Open Access Journals (Sweden)

    Jin-Won Yu

    2017-09-01

    Full Text Available This paper uses optimization techniques to obtain bow hull form of a 66,000 DWT bulk carrier in calm water and in waves. Parametric modification functions of SAC and section shape of DLWL are used for hull form variation. Multi-objective functions are applied to minimize the wave-making resistance in calm water and added resistance in regular head wave of λ/L = 0.5. WAVIS version 1.3 is used to obtain wave-making resistance. The modified Fujii and Takahashi's formula is applied to obtain the added resistance in short wave. The PSO algorithm is employed for the optimization technique. The resistance and motion characteristics in calm water and regular and irregular head waves of the three hull forms are compared. It has been shown that the optimal brings 13.2% reduction in the wave-making resistance and 13.8% reduction in the added resistance at λ/L = 0.5; and the mean added resistance reduces by 9.5% at sea state 5.

  10. Potential pathogenic mechanism for stress fractures of the bowed femoral shaft in the elderly: Mechanical analysis by the CT-based finite element method.

    Science.gov (United States)

    Oh, Yoto; Wakabayashi, Yoshiaki; Kurosa, Yoshiro; Fujita, Koji; Okawa, Atsushi

    2014-11-01

    Stress fractures of the bowed femoral shaft (SBFs) may be one of the causes of atypical femoral fractures (AFFs). The CT-based finite element method (CT/FEM) can be used to structurally evaluate bone morphology and bone density based on patient DICOM data, thereby quantitatively and macroscopically assessing bone strength. Here, we clarify the pathogenic mechanism of SBFs and demonstrate this new understanding of AFFs through mechanical analysis by CT/FEM. A prospective clinical study was performed from April 2012 to February 2014. We assembled two study groups, the bowed AFF group (n=4 patients; mean age, 78.0 years) including those with a prior history of AFF associated with bowing deformity and the thigh pain group (n=14 patients; mean age, 78.6 years) comprising outpatients with complaints of thigh pain and tenderness. Stress concentration in the femoral shaft was analysed by CT/FEM, and the visual findings and extracted data were assessed to determine the maximum principal stress (MPS) and tensile stress-strength ratio (TSSR). In addition, we assessed femoral bowing, bone density, and bone metabolic markers. Wilcoxon's rank sum test was used for statistical analysis. All patients in the bowed AFF group showed a marked concentration of diffuse stress on the anterolateral surface. Thirteen patients in the thigh pain group had no significant findings. However, the remaining 1 patient had a finding similar to that observed in the bowed AFF group, with radiographic evidence of bowing deformity and a focally thickened lateral cortex. Patients were reclassified as having SBF (n=5) or non-SBF (n=13). Statistical analysis revealed significant differences in MPS (p=0.0031), TSSR (p=0.0022), and femoral bowing (lateral, p=0.0015; anterior, p=0.0022) between the SBF and non-SBF groups, with no significant differences in bone density or bone metabolic markers. Significant tensile stress due to bowing deformity can induce AFFs. SBFs should be considered a novel subtype of

  11. Large scale motions of Neptune's bow shock: Evidence for control of the shock position by the rotation phase of Neptune's magnetic field

    Science.gov (United States)

    Cairns, Iver H.; Smith, Charles W.; Kurth, William S.; Gurnett, Donald A.; Moses, Stewart L.

    1991-01-01

    The Voyager 2 spacecraft observed high levels of Langmuir waves before the inbound crossing of Neptune's bow shock, thereby signifying magnetic connection of the bow shock. The Langmuir waves occurred in multiple bursts throughout two distinct periods separated by an 85 minute absence of wave activity. The times of onsets, peaks, and disappearances of the waves were used together with the magnetic field directions and spacecraft position, to perform a 'remote-sensing' analysis of the shape and location of Neptune's bow shock prior to the inbound bow shock crossing. The bow shock is assumed to have a parabolidal shape with a nose location and flaring parameter determined independently for each wave event. The remote-sensing analysis give a shock position consistent with the time of the inbound shock crossing. The flaring parameter of the shock remains approximately constant throughout each period of wave activity but differs by a factor of 10 between the two periods. The absence of waves between two periods of wave activity coincides with a large rotation of the magnetic field and a large increase in the solar wind ram pressure' both these effects lead to magnetic disconnection of the spacecraft from shock. The planetwards motion of the shock's nose from 38.5 R(sub N) to 34.5 R(sub N) during the second time period occurred while the solar wind ram pressure remained constant to within 15 percent. This second period of planetwards motion of the shock is therefore strong evidence for Neptune's bow shock moving in response to the rotation of Neptune's oblique, tilted magnetic dipole. Normalizing the ram pressure, the remotely-sensed shock moves sunwards during the first wave period and planetwards in the second wave period. The maximum standoff distance occurs while the dipole axis is close to being perpendicular to the Sun-Neptune direction. The remote-sensing analysis provides strong evidence that the location of Neptune's bow shock is controlled by Neptune's rotation

  12. Nonlinear wave-particle interaction upstream from the Earth's bow shock

    Directory of Open Access Journals (Sweden)

    C. Mazelle

    2000-01-01

    Full Text Available Well-defined ring-like backstreaming ion distributions have been recently reported from observations made by the 3DP/PESA-High analyzer onboard the WIND spacecraft in the Earth's foreshock at large distances from the bow shock, which suggests a local production mechanism. The maximum phase space density for these distributions remains localized at a nearly constant pitch-angle value for a large number of gyroperiods while the shape of the distribution remains very steady. These distributions are also observed in association with quasi-monochromatic low frequency (~ 50 mHz waves with substantial amplitude (δB/B>0.2. The analysis of the magnetic field data has shown that the waves are propagating parallel to the background field in the right-hand mode. Parallel ion beams are also often observed in the same region before the observation of both the ring-like distributions and the waves. The waves appear in cyclotron resonance with the ion parallel beams. We investigate first the possibility that the ion beams could provide the free energy source for driving an ion/ion instability responsible for the ULF wave occurrence. For that, we solve the wave dispersion relation with the observed parameters. Second, we show that the ring-like distributions could then be produced by a coherent nonlinear wave-particle interaction. It tends to trap the ions into narrow cells in velocity space centered on a well-defined pitch-angle, directly related to the saturation wave amplitude in the analytical theory. The theoretical predictions are in good quantitative agreement with the observations

  13. Bowing, kneeling and 'prostration': athlete's collapse patterns during sudden cardiac arrhythmia/arrest on the field of play.

    Science.gov (United States)

    Baltsezak, Stanislav

    2014-11-01

    Sudden cardiac arrest (SCA) on the field of play remains one of the most tragic and challenging events for a team physician. Even with robust regular preparticipation cardiac screening we cannot prevent all cases of SCA. Ability to recognise imminent cardiac arrest occurring on the field of play remains an important step in managing this condition without delay. You Tube was searched for video clips clearly depicting the sequence of an athlete's collapse of cardiac origin. A pattern of collapse was subsequently analysed. 13 cases were available for public viewing on You Tube and demonstrated the final position of collapse. 12 collapses had full video footage of athlete's fall. All athletes were men. 84.6% (11) cases were from football (soccer). 15.4% (2) of cases were from martial arts. In 10 out of 12 cardiac event cases (83.3%) bowing and/or kneeling were followed by decubitus position. 58.3% (7) of cases demonstrated bowing at the beginning of collapse. 58.3% (7) cases had kneeling as an element of collapse. 61.5% (8 out of 13 cases) of casualties adopted position of 'prostration' (ie, prone) as final stage of collapse. When on the field of play, in the absence of head injury, athletes displaying bowing and/or kneeling positions followed by collapse should be assumed to have a life-threatening cardiac event. Final position of 'prostration' was adopted in over half of cardiogenic collapses. A sports medicine professional should bear this in mind and target his/her assessment and treatment accordingly. When attending such casualties, a defibrillator must be taken to the collapsed player. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  14. STEREO and Wind Observations of Intense Cyclotron Harmonic Waves at the Earth's Bow Shock and Inside the Magnetosheath

    Science.gov (United States)

    Breneman, A. W.; Cattell, C.

    2013-01-01

    We present the first observations of electron cyclotron harmonic waves at the Earth's bow shock from STEREO and Wind burst waveform captures. These waves are observed at magnetic field gradients at a variety of shock geometries ranging from quasi-parallel to nearly perpendicular along with whistler mode waves, ion acoustic waves, and electrostatic solitary waves. Large amplitude cyclotron harmonic waveforms are also observed in the magnetosheath in association with magnetic field gradients convected past the bow shock. Amplitudes of the cyclotron harmonic waves range from a few tens to more than 500 millivolts/meter peak-peak. A comparison between the short (15 meters) and long (100 meters) Wind spin plane antennas shows a similar response at low harmonics and a stronger response on the short antenna at higher harmonics. This indicates that wavelengths are not significantly larger than 100 meters, consistent with the electron cyclotron radius. Waveforms are broadband and polarizations are distinctively comma-shaped with significant power both perpendicular and parallel to the magnetic field. Harmonics tend to be more prominent in the perpendicular directions. These observations indicate that the waves consist of a combination of perpendicular Bernstein waves and field-aligned waves without harmonics. A likely source is the electron cyclotron drift instability which is a coupling between Bernstein and ion acoustic waves. These waves are the most common type of high-frequency wave seen by STEREO during bow shock crossings and magnetosheath traversals and our observations suggest that they are an important component of the high-frequency turbulent spectrum in these regions.

  15. Bow shock specularly reflected ions in the presence of low-frequency electromagnetic waves: a case study

    Directory of Open Access Journals (Sweden)

    K. Meziane

    2004-07-01

    Full Text Available An energetic ion (E≤40 event observed by the CLUSTER/CIS experiment upstream of the Earth's bow shock is studied in detail. The ion event is observed in association with quasi-monochromatic ULF MHD-like waves, which we show modulate the ion fluxes. According to three statistical bow shock position models, the Cluster spacecrafts are located at ~0.5 Re from the shock and the averaged bow shock θBn0 is about ~30°. The analysis of the three-dimensional angular distribution indicates that ions propagating roughly along the magnetic field direction are observed at the onset of the event. Later on, the angular distribution is gyrophase-bunched and the pitch-angle distribution is peaked at α0~θBn0, consistent with the specular reflection production mechanism. The analysis of the waves shows that they are left-handed in the spacecraft frame of reference (right-handed in the solar wind frame and propagate roughly along the ambient magnetic field; we have found that they are in cyclotron-resonance with the field-aligned beam observed just upstream. Using properties of the waves and particles, we explain the observed particle flux-modulation in the context of θBn changes at the shock caused by the convected ULF waves. We have found that the high count rates coincide with particles leaving the shock when θBn angles are less than ~40°, consistent with the specular reflection hypothesis as the production mechanism of ions.

  16. Bow shock specularly reflected ions in the presence of low-frequency electromagnetic waves: a case study

    Directory of Open Access Journals (Sweden)

    K. Meziane

    2004-07-01

    Full Text Available An energetic ion (E≤40 event observed by the CLUSTER/CIS experiment upstream of the Earth's bow shock is studied in detail. The ion event is observed in association with quasi-monochromatic ULF MHD-like waves, which we show modulate the ion fluxes. According to three statistical bow shock position models, the Cluster spacecrafts are located at ~0.5 Re from the shock and the averaged bow shock θBn0 is about ~30°. The analysis of the three-dimensional angular distribution indicates that ions propagating roughly along the magnetic field direction are observed at the onset of the event. Later on, the angular distribution is gyrophase-bunched and the pitch-angle distribution is peaked at α0Bn0, consistent with the specular reflection production mechanism. The analysis of the waves shows that they are left-handed in the spacecraft frame of reference (right-handed in the solar wind frame and propagate roughly along the ambient magnetic field; we have found that they are in cyclotron-resonance with the field-aligned beam observed just upstream. Using properties of the waves and particles, we explain the observed particle flux-modulation in the context of θBn changes at the shock caused by the convected ULF waves. We have found that the high count rates coincide with particles leaving the shock when θBn angles are less than ~40°, consistent with the specular reflection hypothesis as the production mechanism of ions.

  17. Significance of the 'bow and lean test' for the diagnosis of benign horizontal semicircular canal paroxysmal positional vertigo

    Directory of Open Access Journals (Sweden)

    Ying CHEN

    2012-10-01

    Full Text Available Objective To observe and assess the positive rate and accuracy of 'bow and lean test' in the horizontal semicircular canal benign paroxysmal positional vertigo (HSC-BPPV. Methods Ninety-two HSC-BPPV patients who were diagnosed by head roll test (HRT were enrolled, and then further tested with 'bow and lean test' (BLT between Oct 1, 2010 and Sep 30, 2011. They were treated by Barbecue maneuver or Brandt-Daroff exercise on the basis of HRT and BLT tests. The positive rate of BLT test was analyzed, and its accuracy for diagnosis and success rate for treatment of HSC-BPPV were compared between HRT and BLT. Results Among the 92 patients, 83(90.2% of them showed BLT nystagmus. Fifty-seven of 83 (68.7% patients showed both bowing nystagmus and leaning nystagmus, and 18(21.7% and 8(9.6% respectively showed bowing nystagmus alone or leaning nystagmus alone. Among 92 patients, 74(80.4% of them the affected side could be determined by HRT with 69 BLT positive and 5 BLT negative. Among the 69 BLT-positive patients, 60 patients showed the same result of HRT, and successful result was achieved by manipulation. 9 patients showed different result between BLT and HRT, in whom manipulation failed according to the result of HRT, but succeeded when manipulation was performed according to BLT. In 18 patients(19.6% it was not able to determine the affected side by HRT, but in 14 patients manipulation was successful when BLT result was applied. In 4 patients BLT failed to evoke nystagmus, but after practicing Brandt-Daroff exercise, vertigo and HRT nystagmus disappeared 3 days later. Among the 92 patients, 65(70.7% were cured according to HRT, while 83(90.2% got successful result according to BLT(P < 0.05. Conclusion The positive rate and accuracy for HSC-BPPV by BLT are high. It is a useful method for determining the affected side in HSC-BPPV, and to provide the basis for selecting effective manipulation treatment.

  18. Role of In-segregation in anomalously large band-gap bowings of (In,Al,Ga)N

    DEFF Research Database (Denmark)

    Gorczyka, I.; Suski, T.; Christensen, Niels Egede

    2011-01-01

    Large bowings of the band gap and its pressure coefficient in In-containing nitride semiconductor alloys are observed. Photoluminescence measurements for InxGa1-xN and InxAl1-xN combined with other experimental data show large scatter of the results. A comparison with ab-initio calculations...... suggests that this scatter can be ascribed to the formation of In clusters during the sample preparation. The explanation of the observed anomalies taking into account chemical and size effects indicates a specific nature of InN, different from other nitrides and other In-based binary semiconductors....

  19. Compositional bowing of band energies and their deformation potentials in strained InGaAs ternary alloys: A first-principles study

    Energy Technology Data Exchange (ETDEWEB)

    Khomyakov, Petr A.; Luisier, Mathieu; Schenk, Andreas [Integrated Systems Laboratory, Department of Information Technology and Electrical Engineering, ETH Zurich, Gloriastrasse 35, 8092 Zurich (Switzerland)

    2015-08-10

    Using first-principles calculations, we show that the conduction and valence band energies and their deformation potentials exhibit a non-negligible compositional bowing in strained ternary semiconductor alloys such as InGaAs. The electronic structure of these compounds has been calculated within the framework of local density approximation and hybrid functional approach for large cubic supercells and special quasi-random structures, which represent two kinds of model structures for random alloys. We find that the predicted bowing effect for the band energy deformation potentials is rather insensitive to the choice of the functional and alloy structural model. The direction of bowing is determined by In cations that give a stronger contribution to the formation of the In{sub x}Ga{sub 1−x}As valence band states with x ≳ 0.5, compared to Ga cations.

  20. Anti-slamming bulbous bow and tunnel stern applications on a novel Deep-V catamaran for improved performance

    Directory of Open Access Journals (Sweden)

    Mehmet Atlar

    2013-06-01

    Full Text Available While displacement type Deep-V mono hulls have superior seakeeping behaviour at speed, catamarans typically have modest behaviour in rough seas. It is therefore a logical progression to combine the superior seakeeping performance of a displacement type Deep-V mono-hull with the high-speed benefits of a catamaran to take the advantages of both hull forms. The displacement Deep-V catamaran concept was developed in Newcastle University and Newcastle University's own multi-purpose research vessel, which was launched in 2011, pushed the design envelope still further with the successful adoption of a novel anti-slamming bulbous bow and tunnel stern for improved efficiency. This paper presents the hullform development of this unique vessel to understand the contribution of the novel bow and stern features on the performance of the Deep-V catamaran. The study is also a further validation of the hull resistance by using advanced numerical analysis methods in conjunction with the model test. An assessment of the numerical predictions of the hull resistance is also made against physical model test results and shows a good agreement between them.

  1. Large Scale Earth's Bow Shock with Northern IMF as simulated by PIC code in parallel with MHD model

    CERN Document Server

    Baraka, Suleiman M

    2016-01-01

    In this paper, we propose a 3D kinetic model (Particle-in-Cell PIC ) for the description of the large scale Earth's bow shock. The proposed version is stable and does not require huge or extensive computer resources. Because PIC simulations work with scaled plasma and field parameters, we also propose to validate our code by comparing its results with the available MHD simulations under same scaled Solar wind ( SW ) and ( IMF ) conditions. We report new results from the two models. In both codes the Earth's bow shock position is found to be ~14.8 RE along the Sun-Earth line, and ~ 29 RE on the dusk side. Those findings are consistent with past in situ observations. Both simulations reproduce the theoretical jump conditions at the shock. However, the PIC code density and temperature distributions are inflated and slightly shifted sunward when compared to the MHD results. Kinetic electron motions and reflected ions upstream may cause this sunward shift. Species distributions in the foreshock region are depicted...

  2. Understanding the role of Whistler waves at the Bow shock of Earth: MMS observations and dispersion analysis

    Science.gov (United States)

    Wei, H.; Russell, C.; Schwartz, S. J.; An, X.; Strangeway, R. J.

    2016-12-01

    Abundant wave activity is generated at the bow shock of the Earth, that plays an important role in heating the electrons and ions and dissipating the excess energy of supercritical shocks. The Magnetospheric Multiscale (MMS) spacecrafts, with their state-of-the-art plasma and field instruments onboard, allow us to study these waves and better understand the role they play at the bow shock. We have find broad-band waves up to the electron cyclotron frequency across the shock ramp and slightly downstream of it, with large propagation angles with respect to the background magnetic field direction. Simultaneously, the electrons have quite disturbed velocities and are anisotropic in velocity space. In the same region, narrow-band waves at a few hundred Hertz are also observed with durations under a second. These waves are right-handed circularly polarized and propagate along the magnetic field lines. Both wave types are likely to be whistler mode, probably associated with electron streams in the shock ramp. We perform wave analysis of the magnetic and electric fields observed by MMS and carry out dispersion analysis with the guidance of the plasma observations to understand the wave generation and their effects on the shock and magnetosheath plasmas.

  3. Risk Analysis on Leakage Failure of Natural Gas Pipelines by Fuzzy Bayesian Network with a Bow-Tie Model

    Directory of Open Access Journals (Sweden)

    Xian Shan

    2017-01-01

    Full Text Available Pipeline is the major mode of natural gas transportation. Leakage of natural gas pipelines may cause explosions and fires, resulting in casualties, environmental damage, and material loss. Efficient risk analysis is of great significance for preventing and mitigating such potential accidents. The objective of this study is to present a practical risk assessment method based on Bow-tie model and Bayesian network for risk analysis of natural gas pipeline leakage. Firstly, identify the potential risk factors and consequences of the failure. Then construct the Bow-tie model, use the quantitative analysis of Bayesian network to find the weak links in the system, and make a prediction of the control measures to reduce the rate of the accident. In order to deal with the uncertainty existing in the determination of the probability of basic events, fuzzy logic method is used. Results of a case study show that the most likely causes of natural gas pipeline leakage occurrence are parties ignore signage, implicit signage, overload, and design defect of auxiliaries. Once the leakage occurs, it is most likely to result in fire and explosion. Corresponding measures taken on time will reduce the disaster degree of accidents to the least extent.

  4. Recent H-alpha Results on Pulsar B2224+65’s Bow-Shock Nebula, the “Guitar”

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    Timothy Dolch

    2016-09-01

    Full Text Available We used the 4 m Discovery Channel Telescope (DCT at Lowell observatory in 2014 to observe the Guitar Nebula, an Hα bow-shock nebula around the high-velocity radio pulsar B2224+65. Since the nebula's discovery in 1992, the structure of the bow-shock has undergone significant dynamical changes. We have observed the limb structure, targeting the “body” and “neck” of the guitar. Comparing the DCT observations to 1995 observations with the Palomar 200-inch Hale telescope, we found changes in both spatial structure and surface brightness in the tip, head, and body of the nebula.

  5. Atypical Femoral Shaft Fractures in Female Bisphosphonate Users Were Associated with an Increased Anterolateral Femoral Bow and a Thicker Lateral Cortex: A Case-Control Study

    Directory of Open Access Journals (Sweden)

    Seung Pil Jang

    2017-01-01

    Full Text Available The purpose of our study was to investigate the radiographic characteristics of atypical femoral shaft fractures (AFSFs in females with a particular focus on femoral bow and cortical thickness. We performed a fracture location-, age-, gender-, and ethnicity-matched case-control study. Forty-two AFSFs in 29 patients and 22 typical osteoporotic femoral shaft fractures in 22 patients were enrolled in AFSF group and control group, respectively. With comparing demographics between two groups, radiographically measured femoral bow and cortical thicknesses of AFSF group were compared with control group. All AFSF patients were females with a mean age of 74.4 years (range, 58–85 years. All had a history of bisphosphonate (BP use with a mean duration of 7.3 years (range 1–17 years. Femoral bow of AFSF group was significantly higher than control group on both anteroposterior (AP and lateral radiographs after age correction. Mean femoral bow on an AP radiograph was 12.39°±5.38° in AFSF group and 3.97±3.62° in control group (P<0.0001. Mean femoral bow on the lateral radiograph was 15.71°±5.62° in AFSF group and 10.72°±4.61° in control group (after age correction P=0.003. And cortical thicknesses of AFSF group demonstrated marked disparity between tensile and compressive side of bowed femurs in this study. An adjusted lateral cortical thickness was 10.5±1.4 mm in AFSF group and 8.1±1.3 mm in control group (after age correction P<0.0001 while medial cortical thickness of AFSF group was not statistically different from control group. Correlation analysis showed that the lateral femoral bow on the AP radiograph was solely related to lateral CTI (R=0.378, P=0.002. AFSFs in female BP users were associated with an increased anterolateral femoral bow and a thicker lateral cortex of femurs.

  6. [Comparative analysis of edentulous patients treated traditionally and with the use of a face-bow and Quick Master articulator].

    Science.gov (United States)

    Kubrak, J

    1998-01-01

    Correct determination of the occlusal plane is one of the most difficult stages of treatment. After determining the correct occlusal plane its reproduction is possible thanks to the use of articulators. These instruments simulate movements of the jaw in three planes. One of the most optimal articulators is a semi-adjustable type. These instruments are not complicated and give good treatment results. A modern semiadjustable type of articulator is Quick Master. The face-bow which comes together with this instrument is used for recording and transferring the occlusal relation to the articulator. This allows to mount models in an adequate three dimensional position in relation to the temporo-mandibular joint. The use of these instruments leads to many questions and doubts due to difficulties in their use. Therefore the aim of my study was to elaborate a simple method of occlusal recording. I have also compared the treatment results of edentulous patients treated with the use of an articulator and the use of a traditional method. Prosthetic restorations were prepared among 60 patients. The study material was divided into two groups of 30 patients each. In the control group for preparing complete dentures the Gysi method was employed as the most common. In the study group a face-bow and articulator were used. After preparing complete dentures detailed clinical control examinations were carried out and were repeated 24-48 hours after fitting the dentures and also after 3 and 6 months of their use. Working with the face-bow I have employed my own modification of recording the occlusion. The upper wax rim was placed on a slightly warmed bite fork and drawing pins were placed in the recording block to act as a type of key. The lower rim was warmed and brought to occlusal contact a couple of times. Next the face-bow was inserted. The recorded occlusion was transferred and mounted in the articulator. Teeth in both cases were set up similarly to the Gysi method. Lower teeth

  7. Band gap bowings and anomalous pressure effects in III–V nitride alloys: Role of In-segregation

    DEFF Research Database (Denmark)

    Gorczyca, I.; Suski, T.; Christensen, Niels Egede

    2011-01-01

    are most pronounced in InxAl1-xN, (with x=0.25) and depend strongly on clustering geometry. It is shown that the In–N bonds are shortened when more than one In-cation is bound to one nitrogen anion. The strong hybridization of wave functions (In-p,d-states and N-p-states) at the top of the valence band...... and experimental suggestions about the crucial role of In-segregation in InxGa1-xN and InxAl1-xN, different arrangements of In atoms, uniform and clustered are considered. The presence of In and its clustering introduces a significant reduction of both Eg and dEg/dp, as well as strong bowings. These effects...

  8. Bi-2212 and Y123 highly curved single-crystal-like objects: whiskers, bows and ring-like structures

    Science.gov (United States)

    Badica, Petre; Agostino, Angelo; Mizanur Rahman Khan, Mohammad; Cagliero, Stefano; Plapcianu, Carmen; Pastero, Linda; Truccato, Marco; Hayasaka, Yuichiro; Jakob, Gerhard

    2012-10-01

    High-temperature superconducting objects of Bi2Sr2CaCu2O8 and Y Ba2Cu3O7 highly curved in the ab-plane, such as curved/kinked whiskers, bows and ring-like structures, were obtained within a solid-liquid-solid (SLS) grass-like growth mechanism. As-grown objects are crystals with three-dimensional epitaxy similar to conventional single crystals: they can be viewed as crystal parts ‘cut’ from a conventional rectangular crystal. Between our curved objects and conventional crystals, whiskers or thin films there are some differences in the superconducting properties induced only by the shape factors and no new physics is observed. Some details of the growth mechanism are discussed, emphasizing curved-line formation.

  9. Design of a highly nonlinear twin bow-tie polymer photonic quasi-crystal fiber with high birefringence

    Science.gov (United States)

    Su, Wei; Lou, Shuqin; Zou, Hui; Han, Bolin

    2014-03-01

    A twin bow-tie polymer-based photonic quasi-crystal fiber with high birefringence, high nonlinearity and low dispersion as well as maintaining single mode operation is presented in the wavelength range 1.8-2.2 μm. Through optimizing fiber structure parameter using a full-vector finite-element method combined with perfectly matched layers boundary condition, the birefringence is as high as 2.43 × 10-3, the nonlinearity is as high as 118 W-1 km-1, and the dispersion is only 25 ps/nm/km at 2 μm with the holes pitch of 3.3 μm. From the point of fabrication, the influences of deviation of each air hole diameter are discussed to verify the robustness of the photonic quasi-crystal fiber designed.

  10. Acceleration of solar wind ions to 1 MeV by electromagnetic structures upstream of the Earth's bow shock

    Science.gov (United States)

    Stasiewicz, K.; Markidis, S.; Eliasson, B.; Strumik, M.; Yamauchi, M.

    2013-05-01

    We present measurements from the ESA/NASA Cluster mission that show in situ acceleration of ions to energies of 1 MeV outside the bow shock. The observed heating can be associated with the presence of electromagnetic structures with strong spatial gradients of the electric field that lead to ion gyro-phase breaking and to the onset of chaos in ion trajectories. It results in rapid, stochastic acceleration of ions in the direction perpendicular to the ambient magnetic field. The electric potential of the structures can be compared to a field of moguls on a ski slope, capable of accelerating and ejecting the fast running skiers out of piste. This mechanism may represent the universal mechanism for perpendicular acceleration and heating of ions in the magnetosphere, the solar corona and in astrophysical plasmas. This is also a basic mechanism that can limit steepening of nonlinear electromagnetic structures at shocks and foreshocks in collisionless plasmas.

  11. Remote sensing of local structure of the quasi-perpendicular Earth's bow shock by using field-aligned beams

    Directory of Open Access Journals (Sweden)

    B. Miao

    2009-03-01

    Full Text Available Field-aligned ion beams (FABs originate at the quasi-perpendicular Earth's bow shock and constitute an important ion population in the foreshock region. The bulk velocity of these FABs depends significantly on the shock normal angle, which is the angle between shock normal and upstream interplanetary magnetic field (IMF. This dependency may therefore be taken as an indicator of the local structure of the shock. Applying the direct reflection model to Cluster measurements, we have developed a method that uses proton FABs in the foreshock region for remote sensing of the local shock structure. The comparison of the model results with the multi-spacecraft observations of FAB events shows very good agreement in terms of wave amplitude and frequency of surface waves at the shock front.

  12. Quasiparticle self-consistent GW theory of III-V nitride semiconductors: Bands, gap bowing, and effective masses

    DEFF Research Database (Denmark)

    Svane, Axel; Christensen, Niels Egede; Gorczyca, I.

    2010-01-01

    The electronic band structures of InN, GaN, and a hypothetical ordered InGaN2 compound, all in the wurtzite crystal structure, are calculated using the quasiparticle self-consistent GW approximation. This approach leads to band gaps which are significantly improved compared to gaps calculated...... on the basis of the local approximation to density functional theory, although generally overestimated by 0.2–0.3 eV in comparison with experimental gap values. Details of the electronic energies and the effective masses including their pressure dependence are compared with available experimental information....... The band gap of InGaN2 is considerably smaller than what would be expected by linear interpolation implying a significant band gap bowing in InGaN alloys....

  13. Lithium and boron analysis by LA-ICP-MS results from a bowed PWR rod with contact

    Directory of Open Access Journals (Sweden)

    Puranen Anders

    2017-01-01

    Full Text Available A previously published investigation of an irradiated fuel rod from the Ringhals 2 PWR, which was bowed to contact with an adjacent rod, identified a significant but highly localised thinning of the clad wall and increased corrosion. Rod fretting was deemed unlikely due to the adhering oxide covering the surfaces. Local overheating in itself was also deemed insufficient to account for the accelerated corrosion. Instead, an enhanced concentration of lithium due to conditions of local boiling was hypothesised to explain the accelerated corrosion. Studsvik has developed a hot cell coupled LA-ICP-MS (Laser Ablation Inductively Coupled Plasma Mass Spectrometer equipment that enables a flexible means of isotopic analysis of irradiated fuel and other highly active surfaces. In this work, the equipment was used to investigate the distribution of lithium (7Li and boron (11B in the outer oxide at the bow contact area. Depth profiling in the clad oxide at the opposite side of the rod to the point of contact, which is considered to have experienced normal operating conditions and which has a typical oxide thickness, evidenced levels of ∼10–20 ppm 7Li and a 11B content reaching hundreds of ppm in the outer parts of the oxide, largely in agreement with the expected range of Li and B clad oxide concentrations from previous studies. In the contact area, the 11B content was similar to the reference condition at the opposite side. The 7Li content in the outermost oxide closest to the contact was, however, found to be strongly elevated, reaching several hundred ppm. The considerable and highly localised increase in lithium content at the area of enhanced corrosion thus offers strong evidence for a case of lithium induced breakaway corrosion during power operation, when rod-to-rod contact and high enough surface heat flux results in a very local increase in lithium concentration.

  14. Constraining Genome-Scale Models to Represent the Bow Tie Structure of Metabolism for 13C Metabolic Flux Analysis

    Directory of Open Access Journals (Sweden)

    Tyler W. H. Backman

    2018-01-01

    Full Text Available Determination of internal metabolic fluxes is crucial for fundamental and applied biology because they map how carbon and electrons flow through metabolism to enable cell function. 13 C Metabolic Flux Analysis ( 13 C MFA and Two-Scale 13 C Metabolic Flux Analysis (2S- 13 C MFA are two techniques used to determine such fluxes. Both operate on the simplifying approximation that metabolic flux from peripheral metabolism into central “core” carbon metabolism is minimal, and can be omitted when modeling isotopic labeling in core metabolism. The validity of this “two-scale” or “bow tie” approximation is supported both by the ability to accurately model experimental isotopic labeling data, and by experimentally verified metabolic engineering predictions using these methods. However, the boundaries of core metabolism that satisfy this approximation can vary across species, and across cell culture conditions. Here, we present a set of algorithms that (1 systematically calculate flux bounds for any specified “core” of a genome-scale model so as to satisfy the bow tie approximation and (2 automatically identify an updated set of core reactions that can satisfy this approximation more efficiently. First, we leverage linear programming to simultaneously identify the lowest fluxes from peripheral metabolism into core metabolism compatible with the observed growth rate and extracellular metabolite exchange fluxes. Second, we use Simulated Annealing to identify an updated set of core reactions that allow for a minimum of fluxes into core metabolism to satisfy these experimental constraints. Together, these methods accelerate and automate the identification of a biologically reasonable set of core reactions for use with 13 C MFA or 2S- 13 C MFA, as well as provide for a substantially lower set of flux bounds for fluxes into the core as compared with previous methods. We provide an open source Python implementation of these algorithms at https://github.com/JBEI/limitfluxtocore.

  15. Influence of atomic kinetics in the simulation of plasma microscopic properties and thermal instabilities for radiative bow shock experiments.

    Science.gov (United States)

    Espinosa, G; Rodríguez, R; Gil, J M; Suzuki-Vidal, F; Lebedev, S V; Ciardi, A; Rubiano, J G; Martel, P

    2017-03-01

    Numerical simulations of laboratory astrophysics experiments on plasma flows require plasma microscopic properties that are obtained by means of an atomic kinetic model. This fact implies a careful choice of the most suitable model for the experiment under analysis. Otherwise, the calculations could lead to inaccurate results and inappropriate conclusions. First, a study of the validity of the local thermodynamic equilibrium in the calculation of the average ionization, mean radiative properties, and cooling times of argon plasmas in a range of plasma conditions of interest in laboratory astrophysics experiments on radiative shocks is performed in this work. In the second part, we have made an analysis of the influence of the atomic kinetic model used to calculate plasma microscopic properties of experiments carried out on magpie on radiative bow shocks propagating in argon. The models considered were developed assuming both local and nonlocal thermodynamic equilibrium and, for the latter situation, we have considered in the kinetic model different effects such as external radiation field and plasma mixture. The microscopic properties studied were the average ionization, the charge state distributions, the monochromatic opacities and emissivities, the Planck mean opacity, and the radiative power loss. The microscopic study was made as a postprocess of a radiative-hydrodynamic simulation of the experiment. We have also performed a theoretical analysis of the influence of these atomic kinetic models in the criteria for the onset possibility of thermal instabilities due to radiative cooling in those experiments in which small structures were experimentally observed in the bow shock that could be due to this kind of instability.

  16. Simulated solar wind plasma interaction with the Martian exosphere: influence of the solar EUV flux on the bow shock and the magnetic pile-up boundary

    Directory of Open Access Journals (Sweden)

    R. Modolo

    2006-12-01

    Full Text Available The solar wind plasma interaction with the Martian exosphere is investigated by means of 3-D multi-species hybrid simulations. The influence of the solar EUV flux on the bow shock and the magnetic pile-up boundary is examined by comparing two simulations describing the two extreme states of the solar cycle. The hybrid formalism allows a kinetic description of each ions species and a fluid description of electrons. The ionization processes (photoionization, electron impact and charge exchange are included self-consistently in the model where the production rate is computed locally, separately for each ionization act and for each neutral species. The results of simulations are in a reasonable agreement with the observations made by Phobos 2 and Mars Global Surveyor spacecraft. The position of the bow shock and the magnetic pile-up boundary is weakly dependent of the solar EUV flux. The motional electric field creates strong asymmetries for the two plasma boundaries.

  17. Estimation of the Effect of Green Water and Bow Flare Slamming on the Wave-Induced Vertical Bending Moment Using Closed-Form Ex-pressions

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher; Mansour, A. E.

    2003-01-01

    ABSTRACT: The effect of impulsive loads like slamming and green water on deck on the wave-induced bending mo-ment is estimated by a semi-analytical approach. The impulse loads leading to transient vibrations are described in terms of magnitude, phase lag relative to the wave-induced peak and decay...... rate. These loads can be due to bow flare slamming, bottom slamming or green water loads as they all can be characterised by a short duration relative to the wave cycle. The magnitude of the bow flare slamming loads is estimated using accurate results from wedge-shaped sections, Zhao and Faltinsen...... (1993) and for green water loads the results from Buchner (1995) and Wang et al .(1998) are applied. The phase lag relative to the wave-induced peak and the decay rate are derived mainly from published experimental results, Sikora, (1998). The results are given in closed-form expressions...

  18. FEASIBILITY OF WIND TO SERVE UPPER SKAGIT'S BOW HILL TRIBAL LANDS AND FEASIBILITY UPDATE FOR RESIDENTIAL RENEWABLE ENERGY.

    Energy Technology Data Exchange (ETDEWEB)

    RICH, LAUREN

    2013-09-30

    A two year wind resource assessment was conducted to determine the feasibility of developing a community scale wind generation system for the Upper Skagit Indian Tribe's Bow Hill land base, and the project researched residential wind resource technologies to determine the feasibility of contributing renewable wind resource to the mix of energy options for our single and multi-family residential units.

  19. Assessing the potential for rainbow trout reproduction in tributaries of the Mountain Fork River below Broken Bow Dam, southeastern Oklahoma

    Science.gov (United States)

    James M. Long; Trevor A. Starks; Tyler Farling; Robert. Bastarache

    2016-01-01

    Stocked trout (Salmonidae) in reservoir tailwater systems in the Southern United States have been shown to use tributary streams for spawning and rearing. The lower Mountain Fork of the Little River below Broken Bow Dam is one of two year-round tailwater trout fisheries in Oklahoma, and the only one with evidence of reproduction by stocked rainbow trout (Oncorhynchus...

  20. Numerical Study of a Three Dimensional Interaction between two bow Shock Waves and the Aerodynamic Heating on a Wedge Shaped Nose Cone

    Science.gov (United States)

    Wu, N.; Wang, J. H.; Shen, L.

    2017-03-01

    This paper presents a numerical investigation on the three-dimensional interaction between two bow shock waves in two environments, i.e. ground high-enthalpy wind tunnel test and real space flight, using Fluent 15.0. The first bow shock wave, also called induced shock wave, which is generated by the leading edge of a hypersonic vehicle. The other bow shock wave can be deemed objective shock wave, which is generated by the cowl clip of hypersonic inlet, and in this paper the inlet is represented by a wedge shaped nose cone. The interaction performances including flow field structures, aerodynamic pressure and heating are analyzed and compared between the ground test and the real space flight. Through the analysis and comparison, we can find the following important phenomena: 1) Three-dimensional complicated flow structures appear in both cases, but only in the real space flight condition, a local two-dimensional type IV interaction appears; 2) The heat flux and pressure in the interaction region are much larger than those in the no-interaction region in both cases, but the peak values of the heat flux and pressure in real space flight are smaller than those in ground test. 3) The interaction region on the objective surface are different in the two cases, and there is a peak value displacement of 3 mm along the stagnation line.

  1. The effect of an outer-element bow on dryout power and post-dryout heat transfer of a 37-element bundle string

    Energy Technology Data Exchange (ETDEWEB)

    Sutradhar, S.C. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

    2000-07-01

    Dryout and post-dryout tests were performed with a modified 37-element simulated CANDU fuel string, with one outer element of the last bundle gradually bowed toward the flow tube wall. The element had 8% higher heat flux than the remaining outer ring elements and had the narrowest gap between it and the flow-tube wall. The initial dryout occurred on the bowed element for all element-to-wall gap sizes. The dryout power decreased moderately (4% average) as the gap size was reduced to 13.5% of the nominal (unbowed) gap. For smaller than 13.5% gaps, however, the dryout power increased slightly (1.2%) at the low (10.5 kg/s) flow rate and decreased by 5% at the high (16.0 kg/s) flow rate, compared to the nominal gap dryout power. Surface temperatures of the bowed element were recorded for different gap sizes and up to 20% overpower (maximum). The temperature increased by 26% at the maximum overpower as the element was moved from nominal to zero gap position. (author)

  2. A Bow-Tie Genetic Architecture for Morphogenesis Suggested by a Genome-Wide RNAi Screen in Caenorhabditis elegans

    Science.gov (United States)

    Nelson, Matthew D.; Zhou, Elinor; Kiontke, Karin; Fradin, Hélène; Maldonado, Grayson; Martin, Daniel; Shah, Khushbu; Fitch, David H. A.

    2011-01-01

    During animal development, cellular morphogenesis plays a fundamental role in determining the shape and function of tissues and organs. Identifying the components that regulate and drive morphogenesis is thus a major goal of developmental biology. The four-celled tip of the Caenorhabditis elegans male tail is a simple but powerful model for studying the mechanism of morphogenesis and its spatiotemporal regulation. Here, through a genome-wide post-embryonic RNAi-feeding screen, we identified 212 components that regulate or participate in male tail tip morphogenesis. We constructed a working hypothesis for a gene regulatory network of tail tip morphogenesis. We found regulatory roles for the posterior Hox genes nob-1 and php-3, the TGF-β pathway, nuclear hormone receptors (e.g. nhr-25), the heterochronic gene blmp-1, and the GATA transcription factors egl-18 and elt-6. The majority of the pathways converge at dmd-3 and mab-3. In addition, nhr-25 and dmd-3/mab-3 regulate each others' expression, thus placing these three genes at the center of a complex regulatory network. We also show that dmd-3 and mab-3 negatively regulate other signaling pathways and affect downstream cellular processes such as vesicular trafficking (e.g. arl-1, rme-8) and rearrangement of the cytoskeleton (e.g. cdc-42, nmy-1, and nmy-2). Based on these data, we suggest that male tail tip morphogenesis is governed by a gene regulatory network with a bow-tie architecture. PMID:21408209

  3. Habitat ecology and food and feeding of the herring bow crab Varuna litterata (Fabricius, 1798 of Cochin backwaters, Kerala, India

    Directory of Open Access Journals (Sweden)

    P. Lakshmi Devi

    2013-12-01

    Full Text Available Habitat ecology and food and feeding of the herring bow crab, Varuna litterata of Cochin Backwaters, Kerala, India were investigated for a period of one year (April 2011-March 2012. Among the 15 stations surveyed, the crabs were found to occur only in 4 stations, which had a close proximity to the sea. Sediment analysis of the stations revealed that the substratum of these stations is sandy in nature and is rich in organic carbon content (0.79% to 1.07%. These estuarine crabs is euryhaline and are found to be distributed in areas with a sandy substratum, higher organic carbon content and more tidal influx. The stomach contents analysis of crabs examined showed that their diet included crustacean remains, plants, sand and debris, fishes, miscellaneous group and unidentified matter. In adults and sub-adults, crustaceans formed the dominant food group, while in juveniles, sand and debris formed the dominant group. From the present study, V. litterata was found to be a predatory omnivore capable of ingesting both animal and plant tissues.

  4. Lexical study of the bow and arrow game vocabulary and the Parkatêjê log race

    Directory of Open Access Journals (Sweden)

    Marília de Nazaré de Oliveira Ferreira

    2017-09-01

    Full Text Available The work aims to provide subsidies for the documentation and analysis of the Parkatêjê language through the study of the lexicon of two traditional activities of the Parkatêjê people: the log race and the arrow game. For this, we set two lexical fields, log race and bow and arrow game, which were divided into five semantic fields: physical space; steps and processes; human elements; parts, components, specifications, measurements and instruments. Data collection was carried out in situ by applying linguistic questionnaires to informants of three age groups as the stratification made by Ferreira (2005. The development of this research was based on the theoretical postulations from the ethnolinguistics of Coșeriu (1990, Velarde (1991 and Rodrigues (2005, the Lexicology and lexicography (Biderman (2001 and Dubois et al. (1973; and the Lexical field theory from Coșeriu (1977, Abbade (2011 and Dubois et al. (1973. At the end of the study we achieve the structure and organization of the vocabulary that we propose to investigate, as well linguist peculiarities of the lexicon.

  5. Treatment with facemask and removable upper appliance versus modified tandem traction bow appliance: the effects on mandibular space.

    Science.gov (United States)

    Tortop, Tuba; Kaygisiz, Emine; Erkun, Safak; Yuksel, Sema

    2017-10-20

    The aim of this study was to evaluate and compare the mandibular arch posterior space changes in Class III patients treated with facemask (FM) with removable upper appliance or modified tandem traction bow appliance (MTTBA). Pre- and post-treatment and pre- and post-observation lateral cephalograms of 76 subjects with skeletal and dental Class III malocclusion from the period 2000-10 years formed the materials of this study. In the first group, 25 patients (10 girls, 15 boys; mean age: 10 years, 1 month) were treated with MTTBA. The average treatment time was 12 months. In the second group, 26 patients were treated (13 girls, 13 boys; mean age: 10 years, 4 months) with a Delaire-type FM. The average treatment time was 13 months. The remaining 25 children (9 girls, 16 boys; mean age: 9 years, 8 months) were observed without treatment for 10 months. ANOVA, Duncan, and paired t-tests were used for statistical evaluation. Although ramus width and mandibular posterior space increased significantly in all groups, no significant differences were found among the groups. Significant increase in tipping of lower molar (L6/GoMe) in the MTTBA group showed a significant difference compared with the FM and control groups. Significant retroclination of the lower incisors (L1/NB) in the MTTBA and FM treatment groups was significantly different compared with the control group. Retroclination of lower incisors in the MTTBA group was significantly greater than that in the FM group. FM and MTTBA treatment approaches did not affect the dimensions of posterior space. To generalize the results of this study, long term evaluation by considering the third molar position should be done.

  6. Risk analysis using AS/NZS 4360:2004, Bow-Tie diagram and ALARP on construction projects of Banyumanik Hospital

    Science.gov (United States)

    Sari, Diana Puspita; Pujotomo, Darminto; Wardani, Nadira Kusuma

    2017-11-01

    The Determination of risk is an uncertain event. Risks can have negative or positive impacts on project objectives. A project was defined as a series of activities and tasks that have a purpose, specifications, and limits of cost. Banyumanik Hospital Development Project is one of the construction projects in Semarang which have experienced some problems. The first problem is project delays on building stake. The second problem is delay of material supply. Finally, the problem that occurs is less management attention to health safety as evidenced by the unavailability of PPE for the workers. These problems will pose a risk to be a very important risk management performed by contractors at the Banyumanik Hospital Development Project to reduce the impact that would be caused by the risk borne by the provider of construction services. This research aim to risk identification, risk assessment and risk mitigation. Project risk management begins with the identification of risks based on the project life cycle. The risk assessment carried out by AS I NZS 4360: 2004 to the impacts of cost, time and quality. The results obtained from the method of AS I NZS 4360: 2004 is the risk that requires the handling of mitigation. Mitigated risk is the risk that had significant and high level. There are four risks that require risk mitigation with Bow-Tie diagrams which is work accidents, contract delays, material delays and design changes. Bow-Tie diagram method is a method for identifying causal and preventive action and recovery of a risk. Results obtained from Bow-Tie diagram method is a preventive action and recovery. This action is used as input to the ALARP method. ALARP method is used to determine the priority of the strategy proposed in the category broadly acceptable, tolerable, and unacceptable.

  7. Social-value maps for Arapaho, Roosevelt, Medicine Bow, Routt, and White River National Forests, Colorado and Wyoming

    Science.gov (United States)

    Ancona, Zachary H.; Semmens, Darius J.; Sherrouse, Benson C.

    2016-03-25

    Executive SummaryThe continued pressures of population growth on the life-sustaining, economic, and cultural ecosystem services provided by our national forests, particularly those located near rapidly growing urban areas, present ongoing challenges to forest managers. Achieving an effective assessment of these ecosystem services includes a proper accounting of the ecological, economic, and social values attributable to them. However, assessments of ecosystem goods and services notably lack information describing the spatial distribution and relative intensity of social values—the perceived, nonmarket values derived particularly from cultural ecosystem services. A geographic information system (GIS) tool developed to fill this need, Social Values for Ecosystem Services (SolVES; http://solves.cr.usgs.gov), now provides the capability to generate social-value maps at a range of spatial scales. This report presents some of the methods behind SolVES, procedures needed to apply the tool, the first formal map products resulting from its application at a regional scale, and a discussion of the management implications associated with this type of information.In this study, we use SolVES to identify the location and relative intensity of social values as derived from survey responses gathered from residents living in counties adjacent to Arapaho, Roosevelt, Medicine Bow, Routt, and White River National Forests. The results, presented as a series of social-value maps, represent the first publicly available spatial data on social-value intensity for the southern Rocky Mountain region. Our analysis identified high-value areas for social values including aesthetic, biodiversity, and life sustaining within wilderness areas. Other values, like recreation, show high-value areas both within wilderness and throughout the general forest areas, which can be attributed to people using the forests for a diverse set of recreational activities. The economic social-value type was lower

  8. Air quality monitoring in the Bow Corridor : final report December 1999 to August 2001. On-line ed.

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-11-06

    Alberta Environment monitored the air quality of the Bow Corridor and the Cochrane area from December 1999 to August 2001 in an effort to address recent concerns about particulate emissions from industrial, natural and domestic sources as well as concerns about air pollution from traffic along Highway 1 and in communities in the corridor. The Mobile Air Monitoring Laboratory (MAML) monitored air quality at 22 sites in the Cochrane, Exshaw, Canmore and Banff areas. The work included monitoring for sulphur dioxide, particulates, oxides of nitrogen, ozone, hydrocarbons, carbon monoxide, hydrogen sulphide and ammonia using continuous analyzers. In addition, a stationary particulate sampler was used to monitor very small, respirable particulates (PM2.5) as well as larger, inhalable particulates (PM10). Weather parameters such as wind, temperature and relative humidity were also monitored. A passive (no power required) air quality monitoring network was also set up to collect monthly samples of sulphur dioxide at 7 sites and nitrogen dioxide and ozone at 11 different sites. The pollutant levels were compared with air quality levels to Alberta's Ambient Air Quality Guidelines which are some of the most stringent in North America. Maximum one-hour concentrations were : 53 per cent of the one-hour guideline for sulphur dioxide; 15 per cent of the one-hour guideline for nitrogen dioxide; 68 per cent of the one-hour guideline for ozone; 8 per cent of the one-hour guideline for carbon monoxide; 20 per cent of the one-hour guideline for hydrogen sulphide; and 2 per cent of the one-hour guideline for ammonia. These air quality levels were compared to other locations in Alberta. The sources of airborne particulates were wind-blown dust from natural sources, limestone mining operations, manufacturing plants (cement, lime and magnesia), vehicle exhaust from local traffic and Highway 1, and smoke from recreational burning and forest fires. The sources of oxides of nitrogen are

  9. Take a Bow

    Science.gov (United States)

    Spitzer, Greg; Ogurek, Douglas J.

    2009-01-01

    Performing-arts centers can provide benefits at the high school and collegiate levels, and administrators can take steps now to get the show started. When a new performing-arts center comes to town, local businesses profit. Events and performances draw visitors to the community. Ideally, a performing-arts center will play many roles: entertainment…

  10. Technology Must Bow

    Science.gov (United States)

    Milne, Raymond S.

    1973-01-01

    Certain types of technological decision making are socially harmful causing unemployment, inequities of income, and decreased production. Technology should promote the improvement of society, not industry along. Social objectives of the developing countries should be thoroughly examined before instituting any technological decisions. (BL)

  11. ARAMIS project: a more explicit demonstration of risk control through the use of bow-tie diagrams and the evaluation of safety barrier performance.

    Science.gov (United States)

    de Dianous, Valérie; Fiévez, Cécile

    2006-03-31

    Over the last two decades a growing interest for risk analysis has been noted in the industries. The ARAMIS project has defined a methodology for risk assessment. This methodology has been built to help the industrialist to demonstrate that they have a sufficient risk control on their site. Risk analysis consists first in the identification of all the major accidents, assuming that safety functions in place are inefficient. This step of identification of the major accidents uses bow-tie diagrams. Secondly, the safety barriers really implemented on the site are taken into account. The barriers are identified on the bow-ties. An evaluation of their performance (response time, efficiency, and level of confidence) is performed to validate that they are relevant for the expected safety function. At last, the evaluation of their probability of failure enables to assess the frequency of occurrence of the accident. The demonstration of the risk control based on a couple gravity/frequency of occurrence is also possible for all the accident scenarios. During the risk analysis, a practical tool called risk graph is used to assess if the number and the reliability of the safety functions for a given cause are sufficient to reach a good risk control.

  12. Is nitrogen loading in wastewater more important than phosphorus? A historic review of the relationship between algae and macrophyte biomass and wastewater nutrient loading in the Bow River

    Science.gov (United States)

    Taube, Nadine; He, Jianxun; Ryan, Cathy; Valeo, Caterina

    2014-05-01

    The role of nutrient loading on biomass growth in wastewater-impacted rivers is important in understanding how to most effectively optimize wastewater treatment to avoid excessive biomass growth in the receiving water body. Nutrient loading is also affected by the nature of the effluent mixing in the river. This paper relates ammonium (NH4), nitrate (NO3) and total phosphorus (TP) from a wastewater treatment plant (WWTP) to epilithic algae and macrophyte biomass for determination of impacts of the WWTP on the Bow River ecosystem in Calgary, Alberta. Annual macrophyte biomass data and WWTP effluent nutrient data was analyzed for the years from 1981 - 2011. Locally Weighted Scatterplot Smoothing (LOWESS) was used to remove the influence of the river discharge from the biomass. The LOWESS method indicates that macrophytes do not grow beyond a maximum annual discharge of 300m3s-1. Algae biomass was most significantly correlated to daily mean discharge on sampling date and the LOWESS method indicates that they do not grow well beyond a daily mean discharge of 100m3s-1. Correlation analysis suggests that biomass in the Bow River is nitrogen limited. Epilithic algae are significantly correlated (p

  13. Existence or absence of bandgap bowing in II-VI ternary alloys: Comparison between common-anion and common-cation cases

    Science.gov (United States)

    Tit, Nacir; Obaidat, I. M.; Reshak, A. H.; Alawadhi, H.

    2010-02-01

    The common-anion and common-cation II-VI ternary alloys of the family Cd(Zn)Se(Te) are theoretically investigated based on two different methods. Within the virtual-crystal approximation (VCA), both the sp3s*-tight-binding method, with the inclusion of spin-orbit coupling, and the first-principle full-potential linear augmented plane waves (FP-LAPW) technique are employed to determine the alloy constituents' charge states (ionicities) and degree of bond polarity. The results show that: (i) in the common-cation ternary alloys (i.e., CdSexTe1-x and ZnSexTe1-x), the anions alter a strong competition in trapping more charge. Such a competition builds up a compromised effect yielding the bowing behaviour. Whereas, (ii) in the common-anion ternary alloys (i.e., CdyZn1-yTe and CdyZn1-ySe), the absence of such competition would cause the complete absence of bandgap bowing behaviour. The variation of the bandgap is found to be rather close to linear. The obtained good agreement between our theoretical results and the recently available photoluminescence data does further corroborate our claims.

  14. The ratio of specific heats for postshock plasmas of a detached bow shock - An MHD model. [in solar wind-earth interaction

    Science.gov (United States)

    Chao, J. K.; Wiskerchen, M. J.

    1974-01-01

    The empirical relationship between the standoff distance of a detached bow shock (generated by the flow of a supersonic gas past an impenetrable obstacle), the size of the obstacle, the Mach number of the gas, and the ratio of specific heats has been generalized to include the magnetic field. The value of the ratio of specific heats (gamma-prime) in the postshock plasma has been calculated in terms of the preshock Alfvenic and sonic Mach numbers and orientation of the magnetic field. The empirical relationship is further generalized by taking into consideration the normal momentum and energy flux due to waves and/or turbulence and/or heat flow in association with high Mach number shocks. The computed value of gamma prime is substantially modified in comparison with that given by the MHD or the gas dynamic model. For this generalized model the computed gamma prime can be considered to be a more precise thermodynamic quantity, since the macroscopic parameters of the plasma have been separated out. Application of this empirical relationship to the earth's bow shock has been given.

  15. On the impact of isoelectric impurities on band bowing and disorder of compound semiconductors; Ueber den Einfluss von isoelektronischen Stoerstellen auf Bandbiegung und Unordnung in Verbindungshalbleitern

    Energy Technology Data Exchange (ETDEWEB)

    Karcher, Christian

    2012-03-16

    Isolectronic impurities and their impact on the properties of compound semiconductors is discussed in two systems: Nitrogen in Ga(As,P) quantum wells on the one hand and Sulfur and Selenium in bulk ZnTe. The properties are reduced to two experimentally observable aspects: Band Bowing, i.e. the non-linearity of the band gap of the compound semiconductor and disorder, i.e. in particular the formation of a strongly localized density of states beneath the fundamental band gap. Apart of the pure experimental studies an insight into the theoretical model of disorder-induced temperature dependent luminescence properties of the compound semiconductors by means of Monte Carlo Simulations is given.

  16. End-Fire Phased Array 5G Antenna Design Using Leaf-Shaped Bow-Tie Elements for 28/38 GHz MIMO Applications

    DEFF Research Database (Denmark)

    Ojaroudiparchin, Naser; Shen, Ming; Pedersen, Gert F.

    2016-01-01

    In this paper, a new design of mm-Wave phased array 5G antenna for multiple-input multiple-output (MIMO) applications has been introduced. Two identical linear phased arrays with eight leaf-shaped bow-tie antenna elements have been used at different sides of the mobile-phone PCB. An Arlon AR 350...... dielectric with properties of h=0.5 mm, ε=3.5, and δ=0.0026 has been used as a substrate of the proposed design. The antenna is working in the frequency range of 25 to 40 GHz (more than 45% FBW) and can be easily fit into current handheld devices. The proposed MIMO antenna has good radiation performances...... at 28 and 38 GHz which both are powerful candidates to be the carrier frequency of the future 5G cellular networks....

  17. Changes of integral indexes of skilled shooters from a bow under the influence of experimental program of perfection of technical preparedness

    Directory of Open Access Journals (Sweden)

    Antonov S.V.

    2012-12-01

    Full Text Available The aspects of the directed development of co-ordinating capabilities of shooters are considered from a bow. In pedagogical experiment were attracted 45 sportsmen (24 boys, 21 girls. Experiment was lasted by 1 year and included 2 preparatory period of macrocycles. They contained for 20 week's microcycle which were incorporated in four mesocycle. It is set that the substantial increase of effectiveness in control exercises is possible at the correction of orientation of training process on development of co-ordinating capabilities. Trainings facilities of pedagogical direction are selected in relation to development of physical qualities in combination with co-ordinating capabilities. Diminishing of accents of development of the special displays of maximal force is recommended relatively speed-power to endurance. Directions of forming adequate structure of shot technique are set taking into account the specific feelings of competition activity.

  18. Bow-shaped caustics from conical prisms: a 13th-century account of rainbow formation from Robert Grosseteste's De iride.

    Science.gov (United States)

    Harvey, Joshua S; Smithson, Hannah E; Siviour, Clive R; Gasper, Giles E M; Sønnesyn, Sigbjørn O; Tanner, Brian K; McLeish, Tom C B

    2017-07-01

    The rainbow has been the subject of discussion across a variety of historical periods and cultures, and numerous optical explanations have been suggested. Here, we further explore the scientific treatise De iride [On the Rainbow] written by Robert Grosseteste in the 13th century. Attempting to account for the shape of the rainbow, Grosseteste bases his explanation on the optical properties of transparent cones, which he claims can give rise to arc-shaped projections through refraction. By stating that atmospheric phenomena are reducible to the geometric optics of a conical prism, the De iride lays out a coherent and testable hypothesis. Through both physical experiment and physics-based simulation, we present a novel characterization of cone-light interactions, demonstrating that transparent cones do indeed give rise to bow-shaped caustics-a nonintuitive phenomenon that suggests Grosseteste's theory of the rainbow is likely to have been grounded in observation.

  19. Drill-hole data, drill-site geology, and geochemical data from the study of Precambrian uraniferous conglomerates of the Medicine Bow Mountains and Sierra Madre of southeastern Wyoming

    Energy Technology Data Exchange (ETDEWEB)

    Karlstrom, K.E.; Houston, R.S.; Schmidt, T.G.; Inlow, D.; Flurkey, A.J.; Kratochvil, A.L.; Coolidge, C.M.; Sever, C.K.; Quimby, W.F.

    1981-02-01

    This volume is presented as a companion to Volume 1: The Geology and Uranium Potential of Precambrian Conglomerates in the Medicine Bow Mountains and Sierra Madre of Southeastern Wyoming; and to Volume 3: Uranium Assessment for Precambrian Pebble Conglomerates in Southeastern Wyoming. Volume 1 summarized the geologic setting and geologic and geochemical characteristics of uranium-bearing conglomerates in Precambrian metasedimentary rocks of southeastern Wyoming. Volume 3 is a geostatistical resource estimate of U and Th in quartz-pebble conglomerates. This volume contains supporting geochemical data, lithologic logs from 48 drill holes in Precambrian rocks of the Medicine Bow Mountains and Sierra Madre, and drill site geologic maps and cross-sections from most of the holes.

  20. Logs and paleoseismic interpretations from trenches 14C and 14D on the Bow Ridge fault, northeastern Yucca Mountain, Nye County, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Menges, C.M.; Taylor, E.M.; Vadurro, G.; Oswald, J.A.; Cress, R.; Murray, M.; Lundstrom, S.C.; Paces, J.B.; Mahan, S.A.

    1997-12-31

    Detailed studies of trenches 14D and 14C on the Bow Ridge fault indicate two to three displacements and long recurrence intervals during the middle to late Quaternary. The main trace of the fault is marked by a thick (20--40 centimeters wide) subvertical shear zone coated with multiple carbonate-silica laminae and several generations of fine-grained fissure-fill debris. Exposed in the trenches is a vertically stacked sequence of thin (0.3--1.5 meters thick) fine-grained colluvial, alluvial, and eolian deposits that commonly contain smaller wedge-shaped units or several weakly to strongly developed buried paleosols, or both. The two to three surface-rupture events are recognized at discrete stratigraphic intervals in the sequence based on (1) incremental up-section decreases in offset of marker horizons, (b) upward terminations of shear zones, fissure fills, and fractures, and (c) the position of small scarp-derived colluvial wedges deposited adjacent to the fault above downfaulted marker horizons. Preferred estimates of the vertical displacement per event are 12 and 40 centimeters. Left-oblique striations are observed on carbonate fault laminae, which, if tectonic in origin, increase the vertical displacement by factors of 1.1 to 1.7, yielding preferred net slip displacements per event of 13 to 70 centimeters. Thermoluminescence ages of 48 {+-} 20 and 132 {+-} 23 thousand years bracket the ages of the events, which probably occurred near the bounding ages of the time interval. These age constraints suggest long, average recurrence intervals between the three events of 75 to 210 ky; the preferred values range between 100 to 140 ky. The small net cumulative displacement of two dated reference horizons yield very low fault slip rates of 0.002 to 0.007 millimeters per year; the preferred value is 0.003 millimeters per year.

  1. Responsibility of a Filament Eruption for the Initiation of a Flare, CME, and Blast Wave, and its Possible Transformation into a Bow Shock

    Science.gov (United States)

    Grechnev, V. V.; Uralov, A. M.; Kuzmenko, I. V.; Kochanov, A. A.; Chertok, I. M.; Kalashnikov, S. S.

    2015-01-01

    Multi-instrument observations of two filament eruptions on 24 February and 11 May 2011 suggest the following updated scenario for eruptive flare, coronal mass ejection (CME), and shock wave evolution. An initial destabilization of a filament results in stretching out of the magnetic threads belonging to its body that are rooted in the photosphere along the inversion line. Their reconnection leads to i) heating of parts of the filament or its environment, ii) an initial development of the flare cusp, arcade, and ribbons, iii) an increasing similarity of the filament to a curved flux rope, and iv) to its acceleration. Then the pre-eruption arcade enveloping the filament becomes involved in reconnection according to the standard model and continues to form the flare arcade and ribbons. The poloidal magnetic flux in the curved rope developing from the filament progressively increases and forces its toroidal expansion. This flux rope impulsively expands and produces a magnetohydrodynamical disturbance, which rapidly steepens into a shock. The shock passes through the arcade that expands above the filament and then freely propagates for some time ahead of the CME like a decelerating blast wave. If the CME is slow, then the shock eventually decays. Otherwise, the frontal part of the shock changes into the bow-shock regime. This was observed for the first time in the 24 February 2011 event. When reconnection ceases, the flux rope relaxes and constitutes the CME core-cavity system. The expanding arcade develops into the CME frontal structure. We also found that reconnection in the current sheet of a remote streamer forced by the shock passage results in a running flare-like process within the streamer responsible for a type II burst. The development of dimming and various associated phenomena are discussed.

  2. Profiling Radar Observations and Numerical Simulations of a Downslope Wind Storm and Rotor on the Lee of the Medicine Bow Mountains in Wyoming

    Directory of Open Access Journals (Sweden)

    Binod Pokharel

    2017-02-01

    Full Text Available This study describes a downslope wind storm event observed over the Medicine Bow range (Wyoming, USA on 11 January 2013. The University of Wyoming King Air (UWKA made four along-wind passes over a five-hour period over the mountain of interest. These passes were recognized as among the most turbulent ones encountered in many years by crew members. The MacCready turbulence meter aboard the UWKA measured moderate to severe turbulence conditions on each pass in the lee of the mountain range, with eddy dissipation rate values over 0.5 m2/3 s−1. Three rawinsondes were released from an upstream location at different times. This event is simulated using the non-hydrostatic Weather Research and Forecast (WRF model at an inner- domain resolution of 1 km. The model produces a downslope wind storm, notwithstanding some discrepancies between model and rawinsonde data in terms of upstream atmospheric conditions. Airborne Wyoming Cloud Radar (WCR vertical-plane Doppler velocity data from two beams, one pointing to the nadir and one pointing slant forward, are synthesized to obtain a two-dimensional velocity field in the vertical plane below flight level. This synthesis reveals the fine-scale details of an orographic wave breaking event, including strong, persistent downslope acceleration, a strong leeside updraft (up to 10 m·s−1 flanked by counter-rotating vortices, and deep turbulence, extending well above flight level. The analysis of WCR-derived cross-mountain flow in 19 winter storms over the same mountain reveals that cross-mountain flow acceleration and downslope wind formation are difficult to predict from upstream wind and stability profiles.

  3. Use of safety case to accomplish with Brazilian regulations for drilling units; Uso de caso de seguranca para cumprir com as normas brasileiras para unidades de perfuracao: metodologia Bow Tie

    Energy Technology Data Exchange (ETDEWEB)

    Bardy, Mariana; Silveira, Paula Dias; Oliveira, Katia [Det Norske Veritas (DNV), Rio de Janeiro, RJ (Brazil). Risk Advisory

    2012-07-01

    The last accidents on the industry, mainly after BP accident in Texas City and Macondo blowout, showed and increased the importance of safety barriers on prevention of such events. The safety barriers can be identified in risk analysis studies such as Preliminary Hazard Analysis or HAZOP. But, the identification of safety barriers is not enough, it is necessary to maintain their integrity to guarantee that when demanded they work properly as expected. The methodology presented in this document aim to evaluate the integrity condition of safety barriers and their compliance with the project original characteristics using the Bow Tie and an audit process, and searching for actions that can guarantee the barriers integrity when demanded in a proactive way. The Bow Tie diagrams provide a graphic picture of accidental scenarios, join a relational perspective between event, cause, consequence and barriers, and additionally provide a clear view of possible threats and consequences related with events with high damage potential. The application of methodology described in this document is presented based on a case study related to an accidental release of flammable liquid due to dropped objects on the topside of an offshore unit. Among the benefits identified using this proposed methodology it can be highlighted the possibility to form an integrated overview of management system and of factors that can reduce losses. The Bow Tie diagram provides an overview of process accidents, in several different organization levels, and the integration between different areas responsible for management of different barriers groups. Complementing those diagrams with an audit process it can be determined the real image of company management system related to process safety, which make possible the identification of main points for improvement. (author)

  4. THE PLACE OF ARROW AND BOW IN TURKISH GOVERNMENT TRADITION AND SOVEREIGNTY COMPREHENSION OK VE YAYIN TÜRK DEVLET GELENEĞİ VE HÂKİMİYET ANLAYIŞINDAKI YERİ

    Directory of Open Access Journals (Sweden)

    Erkan GÖKSU

    2010-04-01

    Full Text Available The bow and arrow are very important not only being tools of defense or attack but from the culturel point of view for Turks. But these tools that symbolize force, power and strenght, have a special place in state and sovereignty comprehension for Turks who are known archer nation. Finally, bow was accepted as a mark of lordship and arrow as a mark of the vassalege. And also it was seen that arrow and bow were used as a state symbol in some Turkish states. Ok ve yay, Türkler için bir savunma veya saldırı aracı olmasının yanında kültürel bakımdan da büyük öneme sahiptir. Zira okçu millet olarak nitelendirilen Türkler için, genel olarak güç, kuvvet ve kudreti temsil eden bu silahların, devlet ve hâkimiyet anlayışı içerisinde de özel bir yeri vardır. Nitekim Türklerde yay metbuluk, ok ise tâbilik ya da vasallık alameti/sembolü olarak kabul edilmiştir. Hatta bazı Türk devletlerinde, devlet alameti/sembolü olarak ok ve yayın kullanıldığı görülmektedir.

  5. A cadaveric biomechanical study comparing the ease of femoral nail insertion: 1.0- vs 1.5-m bow designs.

    Science.gov (United States)

    Yuan, Huan; Acklin, Yves; Varga, Peter; Gueorguiev, Boyko; Windolf, Markus; Epari, Devakar; Schuetz, Michael; Schmutz, Beat

    2017-05-01

    Anatomic fit of intramedullary nails was suggested by previous studies to improve significantly when the nail radius of curvature (ROC) is closer to the average femoral anatomy. However, no attempt has been made to investigate the impact of different ROC designs on the nail insertion process. Therefore, this biomechanical study quantitatively compared the ease of insertion between femoral intramedullary nails with a 1.0-m and a 1.5-m bow radius. Long TFN-ADVANCED™ (TFNA, 1.0 m ROC) and Proximal Femoral Nail Antirotation nails (PFNA, 1.5 m ROC) were implanted pairwise into seven paired cadaver femora. All bones were reamed 1.5 mm larger than the nail diameter. Using a material testing machine, intramedullary nailing was then performed stepwise with 20-mm steps and a 10-mm/s insertion rate, and force was measured. The nail deformation caused by the insertion was assessed through 3D computer models built from pre- and post-nailing CT scans. The ease of insertion between TFNA and PFNA nails was quantified in terms of insertion force, insertion energy and nail deformation. There was no significant difference in the peak force generated during nailing between TFNA and PFNA nails (P = 0.731). However, the force measured at the end of insertion (P = 0.002) was significantly smaller in TFNA nails compared to PFNA nails. After implantation, TFNA nails showed significantly smaller deformation when compared to PFNA nails (P = 0.005, both ends aligned). Furthermore, less energy was required to insert TFNA nails; however, the difference was not significant (P = 0.25). Compared to PFNA nails, a significant decrease in insertion force and nail deformation was found at the end of insertion for TFNA nails. Results suggest that TFNA having a 1.0-m ROC is easier to insert for the set of femora used in this study compared to PFNA with a 1.5-m ROC.

  6. SURVEY, SILVER BOW COUNTY, MT

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Survey data includes spatial datasets and data tables necessary to digitally represent data collected in the survey phase of the study. (Source: FEMA Guidelines and...

  7. Sailing comfort through axe bow

    NARCIS (Netherlands)

    Verdult, E.

    2012-01-01

    Every year, the Royal Netherlands Sea Rescue Institution (KNRM) heads out to sea 2000 times to rescue people. In conditions with high waves, the lifeboats hit the water so hard that the crew have diffilty keeping upright in the pilot house. Sailing slowly is therefore the only option. But the boats

  8. Another string.... but no bow.

    LENUS (Irish Health Repository)

    Green, Connor

    2011-04-01

    Based on a positive personal experience, the authors advocate the use of a wound protector\\/retractor such as the Alexis system in total hip arthroplasty, to avoid intra-operative bacterial contamination from the skin, while avoiding damage to the skin and other soft tissues.

  9. Madeiras utilizadas na fabricação de arcos para instrumentos de corda: aspectos anatômicos Anatomical features of woods used in the manufacture of bows for stringed instruments

    Directory of Open Access Journals (Sweden)

    Veronica Angyalossy

    2005-12-01

    Full Text Available A madeira de pau-brasil (Caesalpinia echinata Lam. é mundialmente empregada na confecção de arcos para instrumentos de corda, uma vez que apresenta características únicas de ressonância, densidade, durabilidade, beleza, entre outras qualidades, que a tornam ideal para tal uso. Diferentes amostras de pau-brasil, contudo, fornecem arcos com qualidades distintas. No comércio nacional outras madeiras estão sendo empregadas na produção de arcos. Realizou-se, neste estudo, uma análise qualitativa e quantitativa de diferentes amostras de pau-brasil com o objetivo de apontar diferenças na estrutura da madeira que possam contribuir para o entendimento das causas da variação na qualidade do arco, além da análise de outras espécies objetivando determinar, do ponto de vista estrutural, semelhanças ou diferenças com o pau-brasil. Conclui-se que variações no diâmetro dos vasos, distribuição e quantidade de parênquima axial e orientação dos elementos axiais e radiais são parâmetros que devem ser considerados quando se busca determinar as causas das diferenças na qualidade dos arcos de pau-brasil. Constatou-se que arcos de boa qualidade apresentam grã linheira e textura fina. Esta última característica decorre da menor proporção de vasos cujo diâmetro é reduzido, raios homogêneos e fibras com paredes espessas e/ou muito espessas. Assim, a relação entre a estrutura e a qualidade do arco está diretamente relacionada com as dimensões, a distribuição e a proporção das células do lenho.Pernambuco wood (Caesalpinia echinata Lam. has special characteristics like resonance, density, durability, and beauty; for this reason, it is considered the best material for stringed instruments bows. Besides pernambuco wood has been used around the world, some samples, and consequently some bows, are better than others. In Brazil, others woody species have been used in the manufacture of bows. In this paper some wood samples of

  10. Lithology, fault displacement, and origin of secondary calcium carbonate and opaline silica at Trenches 14 and 14D on the Bow Ridge Fault at Exile Hill, Nye County, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, E.M.; Huckins, H.E.

    1995-02-01

    Yucca Mountain, a proposed site for a high-level nuclear-waste repository, is located in southern Nevada, 20 km east of Beatty, and adjacent to the southwest comer of the Nevada Test Site (NTS) (fig. 1). Yucca Mountain is located within the Basin and Range province of the western United States. The climate is semiarid, and the flora is transitional between that of the Mojave Desert to the south and the Great Basin Desert to the north. As part of the evaluation, hydrologic conditions, especially water levels, of Yucca Mountain and vicinity during the Quaternary, and especially the past 20,000 years, are being characterized. In 1982, the US Geological Survey, in cooperation with the US Department of Energy (under interagency agreement DE-A104-78ET44802), excavated twenty-six bulldozer and backhoe trenches in the Yucca Mountain region to evaluate the nature and frequency of Quaternary faulting (Swadley and others, 1984). The trenches were oriented perpendicular to traces of suspected Quaternary faults and across projections of known bedrock faults into Quaternary deposits. Trench 14 exposes the Bow Ridge Fault on the west side of Exile Hill. Although the original purpose of the excavation of trench 14 was to evaluate the nature and frequency of Quaternary faulting on the Bow Ridge Fault, concern arose as to whether or not the nearly vertical calcium carbonate (the term ``carbonate`` in this study refers to calcium carbonate) and opaline silica veins in the fault zone were deposited by ascending waters (ground water). These veins resemble in gross morphology veins commonly formed by hydrothermal processes.

  11. [Bow legged adjectives in ancient literature].

    Science.gov (United States)

    Simon, Frantisek; Steger, Florian

    2011-01-01

    This article addresses the issue of capturing the medical entity called 'curved legs' in a terminologically exact way. In so doing, it refers to the long-lasting process of differentiation of exact nuances of meaning in Ancient Greek and Latin. In the chronological perusal of ancient Greek literature, it becomes evident that the various adjectives employed are often vague when looking at non-medical literature. By contrast, in the Hippocratic corpus these terms are for the first time annotated with explanations intended to lead to a more precise understanding of the described deformity. Further attempts of differentiation can be found in the writings of Galen, who not only distinguishes between outward and inward curvatures, but also between deformities of the thigh and lower leg as well as between pathological and natural curvatures. Latin literature also provides a series of adjectives that were initially often used in the meaning of 'curved' but it was not until Celsus that these were differentiated with respect to the type and direction of the curvature. When comparing Greek and Latin adjectives, it turns out that though the Latin term blaesus can be traced back etymologically to the Greek word beta lambda alpha iota sigma ó zeta, the meaning of beta lambda alpha iota sigma ó zeta does not fully correspond to that of the Latin word. It is not before the later common transliteration of Greek words that this adjective took on the meaning of beta lambda alpha iota sigma ó zeta; however, this was finally lost again. In summary, the article concludes that exact word meanings in ancient literature are often unclear and precise ascriptions of meanings are inconsistent. In the case of "curved legs," this has led to misunderstandings regarding the respective types and directions of the curvature.

  12. Leaders bow heads for synagogue tragedy

    Index Scriptorium Estoniae

    2005-01-01

    4. juulil 1941 põletasid natsid Riias maha sünagoogi, mille käigus võis hukkuda kuni 2000 juuti. 4. juuli mälestustseremoonial osales hulk tipp-poliitikuid ja väliskülalisi, kellele Iisraeli suursaadik Gary Koren pani südamele propageerida antisemitismi null-tolerantsi Lätis

  13. Bell's Spaceships: The Views from Bow and Stern

    Science.gov (United States)

    Lewis, Geraint F.; Barnes, Luke A.; Sticka, Martin J.

    2018-01-01

    Unravelling apparent paradoxes has proven to be a powerful tool for understanding the complexities of special relativity. In this paper, we focus upon one such paradox, namely Bell's spaceship paradox, examining the relative motion of two uniformly accelerating spaceships. We consider the view from either spaceship, with the exchange of photons between the two. This recovers the well-known result that the leading spaceship loses sight of the trailing spaceship as it is redshifted and disappears behind what is known as the `Rindler horizon'. An immediate impact of this is that if either spaceship tries to measure the separation through `radar ranging', bouncing photons off one another, they would both eventually fail to receive any of the photon `pings' that they emit. We find that the view from this trailing spaceship is, however, starkly different, initially, seeing the leading spaceship with an increasing blueshift, followed by a decreasing blueshift. We conclude that, while the leading spaceship loses sight of the trailing spaceship, for the trailing spaceship the view of the separation between the two spaceships, and the apparent angular size of the leading spaceship, approach asymptotic values. Intriguingly, for particular parameterisation of the journey of the two spaceships, these asymptotic values are identical to those properties seen before the spaceships began accelerating, and the view from the trailing spaceship becomes identical to when the two spaceships were initially at rest.

  14. Tibial Bowing and Pseudarthrosis in Neurofibromatosis Type 1

    Science.gov (United States)

    2015-01-01

    University of Plymouth, Peninsula College of Medicine and Dentistry , Plymouth, UK 15The Neurofibromatosis Institute, La Crescenta, California...genetic origins. Acta Paediatr 2009;98:693–8. 6 Thiel C, Wilken M, Zenker M, Sticht H, Fahsold R, Gusek-Schneider GC, Rauch A. Independent NF1 and PTPN11

  15. Plane wave scattering by bow-tie posts

    Science.gov (United States)

    Lech, Rafal; Mazur, Jerzy

    2004-04-01

    The theory of scattering in free space by a novel structure of a two-dimensional dielectric-metallic post is developed with the use of a combination of a modified iterative scattering procedure and an orthogonal expansion method. The far scattered field patterns for open structures are derived. The rotation of the post affects its scattered field characteristic, which permits to make adjustments in characteristic of the posts arrays.

  16. Hierarchical modularity of nested bow-ties in metabolic networks

    OpenAIRE

    Zhao, Jing; Yu, Hong; Luo, Jian-Hua; Cao, Zhi-Wei; Li, Yi-Xue

    2006-01-01

    Abstract Background The exploration of the structural topology and the organizing principles of genome-based large-scale metabolic networks is essential for studying possible relations between structure and functionality of metabolic networks. Topological analysis of graph models has often been applied to study the structural characteristics of complex metabolic networks. Results In this work, metabolic networks of 75 organisms were investigated from a topological point of view. Network decom...

  17. CERN Takes a Bow at the Montreux Jazz Festival

    CERN Multimedia

    CERN Bulletin

    2013-01-01

    A year after CERN announced the discovery of a Higgs boson on the world stage, several of the participating scientists found themselves in a new and unfamiliar arena – the renowned Montreux Jazz Festival.   The Canettes Blues Band of the CERN Music Club performing live on the Music In The Park stage at the Montreux Jazz Festival, on 18 July. CERN and the Montreux Jazz Foundation teamed up this summer to host a series of seminars and performances titled “The Physics of Music and the Music of Physics”.  The seminars took place in the historic Petit Palais and included a variety of presentations on the interplay between science and sound. Sound artist Bill Fontana kicked off the series by presenting the concepts and methods behind the creation of  “sound sculptures”.  As the current Collide@CERN artist-in-residence, Fontana has been placing microphones and sensors on accelerators, detectors and other objects at CERN t...

  18. Plasmonic eigenmodes in individual and bow-tie graphene nanotriangles

    DEFF Research Database (Denmark)

    Wang, Weihua; Christensen, Thomas; Jauho, Antti-Pekka

    2015-01-01

    In classical electrodynamics, nanostructured graphene is commonly modeled by the computationally demanding problem of a three-dimensional conducting film of atomic-scale thickness. Here, we propose an efficient alternative two-dimensional electrostatic approach where all calculation procedures...... are restricted to the graphene sheet. Furthermore, to explore possible quantum effects, we perform tight-binding calculations, adopting a random-phase approximation. We investigate multiple plasmon modes in 20 nm equilateral triangles of graphene, treating the optical response classically as well as quantum...... and even more reduced for zigzag edges. Our various results illustrate a surprising phenomenon: Even 20 nm large graphene structures clearly exhibit quantum plasmonic features due to atomic-scale details in the edge termination....

  19. Band gap bowing in quaternary nitride semiconducting alloys

    DEFF Research Database (Denmark)

    Gorczyka, Isabela; Suski, T.; Christensen, Niels Egede

    2011-01-01

    Structural properties of InxGayAl1−x−yN alloys are derived from total-energy minimization within the local-density approximation (LDA). The electronic properties are studied by band structure calculations including a semiempirical correction for the “LDA gap error.” The effects of varying...

  20. Buffer Bulbous Bows: A Measure to Reduce Oil Spill in Collisions

    DEFF Research Database (Denmark)

    Yamada, Yasuhira

    2007-01-01

    Formålet med denne afhandling at undersøge, hvor meget man ville kunne reducere olieudslip forårsaget af skibskollisioner ved at indføre mindre stærke bulbstævne på verdens skibe. Analysen omfatter såvel deterministiske som probabilistiske metoder. Afhandlingen består af et sammendrag og fem publ...

  1. The Lynn Maxilla Rotator Combination Appliance and Lynn Archial Face Bow.

    Science.gov (United States)

    Lynn, J M

    1989-01-01

    This combination orthopedic traction appliance offers a new dimension in treating long faced, mouth breathing patients, who generally exhibit pre-maxillary gingival excess and lip incompetency or a short upper lip. The dynamics of excessive clockwise growth can be reversed if the physical pressures placed on the craniofacial skeletal tissues are reversed. In many instances extraction therapy or orthognatic surgery may be unnecessary to achieve acceptable occlusion and facial esthetics. Dr. Ullrich Teuscher, M.D., D.M.D., of Zurich, Switzerland published an article in the American Journal of Orthodontics in 1978, which addressed a growth related traction treatment of Class II facial patterns. This appliance expands on this concept with important modifications. There are many causes of a "long face". One of the primary causes, however, is upper airway compromise. This may be a result of enlargement of the tonsils, adenoids, nasal tubinates, nasal polyps, hemangiomas, allergies, nasal septal deviations, nasal floor narrowing, etc. In our Westernized society of "non-chewing" youths (most fast or processed food we eat today is practically pre-chewed or per-digested), the orofacial musculature is lacking in functional use. This condition further enhances the lack of full facial development because the necessary forces transmitted from the masticatory musculature to the facial skeleton are lacking. Therefore, if a person has tendencies toward a narrow-face, nasal vault, etc., there is no chance that nature's inherent counterbalancing forces will have any positive effect in resolving the airway compromise by producing wide or broad dental arches, because these forces do not exist anymore as a result of no necessity to chew food. The purpose of this paper is not to study the etiology of upper respiratory compromise, but rather to suggest a possible treatment alternative which sequentially counteracts the undesirable forces placed on the craniofacial skeleton by the aforementioned pathologies or environmental conditions.

  2. [Deep venous thrombosis of the upper limb in a violin player: The "bow syndrome"].

    Science.gov (United States)

    Sanson, H; Gautier, V; Stansal, A; Sfeir, D; Franceschi, C; Priollet, P

    2016-12-01

    Exercise-induced thrombosis is a rare cause of deep venous thrombosis (DVT) of the upper limb and usually affects young subjects without comorbid conditions. The diagnosis may be challenging. A 23-year-old female right-handed French teacher and amateur violin player presented with edema of the root of the right arm associated with erythrocyanosis of the extremity and collateral circulation of the shoulder. History taking revealed oral contraception and recent change in violin playing habits. D-dimers were negative. A second duplex-Doppler was required before visualization of a DVT in the right subclavian vein. The patient was given low-molecular-weight heparin alone, followed by rivaroxaban. The outcome was very favorable at 48h. The patient was seen at 4 months and had not had a recurrent episode. The diagnosis of DVT of the upper limb is basically clinical. There is a clinical probability score for the introduction of anticoagulation even if the duplex-Doppler fails to visualize DVT, a situation that can occur due to the clavicular superposition in this region. Exercise-induced DVT should be suspected in patients with minimally intense but repeated exercise (hyper-abduction), e.g. as here playing the violin. Anticoagulation is the treatment of choice. The role for surgery and pharmacomechanical strategies remains to be defined. Exercise-induced thrombosis (Paget-Schroetter syndrome) should be suspected in young patients free of any comorbidity who develop a thrombosis of the upper limb. Studies comparing different therapeutic options would be useful to achieve more homogeneous management practices despite the heterogeneous clinical presentations. Copyright © 2016. Published by Elsevier Masson SAS.

  3. A frequency-based characterization of spiccato bowing in violin performance.

    Science.gov (United States)

    Shan, Gongbing; Visentin, Peter; Wooldridge, Luke; Wang, Changdong; Connolly, Dennis

    2007-12-01

    Performance of instrumental music requires high precision and the automisation of motor control to free the performer to focus on the artistic outcome. To acquire this high skill, training is experience-based, involves one-on-one instruction, and requires long hours of repetitive practice. This approach is consistent with a traditional model of vocational apprenticeship. Practice habits and long hours associated with training have been identified as sometimes contributing to high rates of vocational injury among musicians. This study explores violin performance, identifying generalizable perceptual markers to bridge the gap between science and experience in pedagogical methodology. Kinematic data were collected using 3-D motion capture. Dynamic modeling was used to specify internal loads. Eleven professional-level musicians were tested, ranging in age from 21 to 47 years (M = 36 yr., SD = 6). The study identified several motor-learning markers, speed-dependent motor control phases (increasing effort, optimization, and approaching physiological limits), string-dependent motor control, and an unexpected sympathetic resonance between the two arms, notwithstanding their very different functions. This study suggests that instrumental performance could be aided by identifying markers related to musical outcomes, performers' perceptions, and motor skill acquisition.

  4. Constraining Relativistic Bow Shock Properties in Rotation-powered Millisecond Pulsar Binaries

    Science.gov (United States)

    Wadiasingh, Zorawar; Harding, Alice K.; Venter, Christo; Böttcher, Markus; Baring, Matthew G.

    2017-04-01

    Multiwavelength follow-up of unidentified Fermi sources has vastly expanded the number of known galactic-field “black widow” and “redback” millisecond pulsar binaries. Focusing on their rotation-powered state, we interpret the radio to X-ray phenomenology in a consistent framework. We advocate the existence of two distinct modes differing in their intrabinary shock orientation, distinguished by the phase centering of the double-peaked X-ray orbital modulation originating from mildly relativistic Doppler boosting. By constructing a geometric model for radio eclipses, we constrain the shock geometry as functions of binary inclination and shock standoff R 0. We develop synthetic X-ray synchrotron orbital light curves and explore the model parameter space allowed by radio eclipse constraints applied on archetypal systems B1957+20 and J1023+0038. For B1957+20, from radio eclipses the standoff is R 0 ˜ 0.15-0.3 fraction of binary separation from the companion center, depending on the orbit inclination. Constructed X-ray light curves for B1957+20 using these values are qualitatively consistent with those observed, and we find occultation of the shock by the companion as a minor influence, demanding significant Doppler factors to yield double peaks. For J1023+0038, radio eclipses imply R 0 ≲ 0.4, while X-ray light curves suggest 0.1 ≲ R 0 ≲ 0.3 (from the pulsar). Degeneracies in the model parameter space encourage further development to include transport considerations. Generically, the spatial variation along the shock of the underlying electron power-law index should yield energy dependence in the shape of light curves, motivating future X-ray phase-resolved spectroscopic studies to probe the unknown physics of pulsar winds and relativistic shock acceleration therein.

  5. "Not Tied Up Neatly with a Bow": Professionals' Challenging Cases in Informed Consent for Genomic Sequencing.

    Science.gov (United States)

    Tomlinson, Ashley N; Skinner, Debra; Perry, Denise L; Scollon, Sarah R; Roche, Myra I; Bernhardt, Barbara A

    2016-02-01

    As the use of genomic technology has expanded in research and clinical settings, issues surrounding informed consent for genome and exome sequencing have surfaced. Despite the importance of informed consent, little is known about the specific challenges that professionals encounter when consenting patients or research participants for genomic sequencing. We interviewed 29 genetic counselors and research coordinators with considerable experience obtaining informed consent for genomic sequencing to understand their experiences and perspectives. As part of this interview, 24 interviewees discussed an informed consent case they found particularly memorable or challenging. We analyzed these case examples to determine the primary issue or challenge represented by each case. Challenges fell into two domains: participant understanding, and facilitating decisions about testing or research participation. Challenges related to participant understanding included varying levels of general and genomic literacy, difficulty managing participant expectations, and contextual factors that impeded participant understanding. Challenges related to facilitating decision-making included complicated family dynamics such as disagreement or coercion, situations in which it was unclear whether sequencing research would be a good use of participant time or resources, and situations in which the professional experienced disagreement or discomfort with participant decisions. The issues highlighted in these case examples are instructive in preparing genetics professionals to obtain informed consent for genomic sequencing.

  6. Theoretical research program to study chemical reactions in AOTV bow shock tubes

    Science.gov (United States)

    Taylor, Peter R.

    1993-01-01

    The main focus was the development, implementation, and calibration of methods for performing molecular electronic structure calculations to high accuracy. These various methods were then applied to a number of chemical reactions and species of interest to NASA, notably in the area of combustion chemistry. Among the development work undertaken was a collaborative effort to develop a program to efficiently predict molecular structures and vibrational frequencies using energy derivatives. Another major development effort involved the design of new atomic basis sets for use in chemical studies: these sets were considerably more accurate than those previously in use. Much effort was also devoted to calibrating methods for computing accurate molecular wave functions, including the first reliable calibrations for realistic molecules using full CI results. A wide variety of application calculations were undertaken. One area of interest was the spectroscopy and thermochemistry of small molecules, including establishing small molecule binding energies to an accuracy rivaling, or even on occasion surpassing, the experiment. Such binding energies are essential input to modeling chemical reaction processes, such as combustion. Studies of large molecules and processes important in both hydrogen and hydrocarbon combustion chemistry were also carried out. Finally, some effort was devoted to the structure and spectroscopy of small metal clusters, with applications to materials science problems.

  7. Influence of Bow-Wave Breaking on the Added Resistance of Fast Ships

    NARCIS (Netherlands)

    Choi, B.

    2018-01-01

    The publication of the Energy Efficiency Design Index (EEDI) by the International Maritime Organization (IMO) has recently stimulated the accurate assessment of actual sea performance of ships, which is evaluated as added resistance in waves. However, a satisfactory consensus on the evaluation

  8. Mapping the Structure of Directed Networks: Beyond the Bow-Tie Diagram

    Science.gov (United States)

    Timár, G.; Goltsev, A. V.; Dorogovtsev, S. N.; Mendes, J. F. F.

    2017-02-01

    We reveal a hierarchical, multilayer organization of finite components—i.e., tendrils and tubes—around the giant connected components in directed networks and propose efficient algorithms allowing one to uncover the entire organization of key real-world directed networks, such as the World Wide Web, the neural network of Caenorhabditis elegans, and others. With increasing damage, the giant components decrease in size while the number and size of tendril layers increase, enhancing the susceptibility of the networks to damage.

  9. Bedraggled Ballerinas on a Bus Back to Bow: The ‘Fairy Business’

    Directory of Open Access Journals (Sweden)

    Anne Witchard

    2011-09-01

    Full Text Available This paper begins to explore cultural connections between mid-Victorian music hall and dance modernism by looking at the role of the female dancer and her traverse of the socio-geographical space between the East End and the West End. I argue that by examining the ‘lost’ history of music-hall ballet we might find an indigenous performative tradition that presupposes the impact of the Ballets Russes on the London stage.

  10. Numerical Study on the Effect of Buffer Bow Structure in Ship-to-ship Collisions

    DEFF Research Database (Denmark)

    Yamada, Yasuhira; Endo, Hisayoshi; Pedersen, Preben Terndrup

    2005-01-01

    A disastrous oil spill from a struck oil tanker has become one of the major problems in view of conservation of maritime environment. So far double hulls (D/H) have been introduced to reduce the consequences of collision and grounding events In order to further reduce the oil spill from struck oil...... a very large crude oil carrier (VLCC) in ballast condition collides with the midship region of a D/H VLCC in a laden condition. Fracture of fillet welds, elastic-plastic material properties and strain rate effects, are taken into account in the simulations. The effect of the equivalent failure strain (FS...

  11. Risk assessment in gas and oil pipelines based on the fuzzy Bow-tie technique

    Directory of Open Access Journals (Sweden)

    P. Heyrani

    2016-04-01

      Conclusion: Considering the recognized factors leading to destruction of pipelines and their most notable outcomes, instructions on how to control and reduce the potential consequences were suggested, with emphasis on the removal of the most probable causes.

  12. Bow Wave Measurements of the R/V Athena I: 2004

    Science.gov (United States)

    2005-12-01

    YAG laser, with an output of 2.5-3.0 watts at 532 nm (Melles-Griot Model MLM -0532). The laser sheet was imaged by two black and white, progressive scan...operating speeds where data were obtained. The time-averaged measurements seem to give good agreement with the predictions, at least in this case

  13. Early treatment of Class III malocclusion with a tandem traction bow appliance

    Directory of Open Access Journals (Sweden)

    Sneha Basaveshwar Valgadde

    2016-01-01

    Full Text Available Since Class III malocclusion is progressive in nature, the facial growth of Class III malocclusion worsens with age. Class III malocclusion is associated with a deviation in the sagittal relationship of the maxilla and the mandible, characterized by a deficient maxilla, retrognathic mandible, or a combination of both. The early orthopedic treatment of Class III malocclusions, at the end of primary dentition or the beginning of mixed dentition, prior to growth spurt, allows the accomplishment of successful results, providing facial balance, modifying the maxillofacial growth and development, and in many instances, preventing a future surgical treatment by increasing the stability. Many treatment approaches can be found in the literature regarding orthopedic and orthodontic treatment of Class III malocclusion, including intra- and extra-oral appliances. The major problem with extraoral anchorage has been of patient compliance due to its physical appearance. The case report presents an intraoral modified tandem appliance for maxillary protraction that has been used clinically to achieve successful results without relying much on patient co-operation.

  14. Propeller Design Optimization for Tunnel Bow Thrusters in the Bollard Pull Condition

    Science.gov (United States)

    2012-06-01

    cavitation risk . Beam theory was applied to determine stresses and calculate appropriate thicknesses. The sections were kept symmetric with respect to...initialization are included as Appendix D. 24 Motor Parameters Manufacturer Parker Back emf Constant 112.09 V/krpm Units Metric Resistance 2.97...avoid the need to open the motor housing and risk the watertight integrity of the fixture, additional thrust calibration runs were completed in an

  15. FAILURES AND DEFECTS IN THE BUILDING PROCESS – APPLYING THE BOW-TIE APPROACH

    DEFF Research Database (Denmark)

    Jørgensen, Kirsten

    2009-01-01

    Function failures, defects, mistakes and poor communication are major problems for the construction sector. A Danish research project focusing on failures and defects in building processes has been carried out over the last 2 years. As the empirical element in the research, a large construction...

  16. Bow Wave Measurements of the R/V Athena 1: 2003

    Science.gov (United States)

    2005-12-01

    unobstructed images. QViz Comuters Laser Scanning Mirror C rCamra 1 Camera 2 Figure 3: Ship-board quantitative flow visualization schematicL__5 Camara 3...developed at NSWCCD using National Instruments LabView software with the Image Processing ( Vision ) toolbox was used to determine the surface profile

  17. Bowing in the Right Direction: Hiland Mountain Correctional Center Women's String Orchestra Programme

    Science.gov (United States)

    Warfield, Duane

    2010-01-01

    The Hiland Mountain Correctional Center, a 400-bed facility for multi-level adult female offenders in Eagle River, Alaska, offers a unique educational programme to its prisoners: an orchestra. Founded in 2003, by volunteer Pati Crofut, orchestra membership grew from eight to 22 female offenders between 2003 and 2009. Crofut has devoted her time…

  18. Spatial scales of the magnetic ramp at the Venusian bow shock

    OpenAIRE

    A. P. Dimmock; Walker, S.N.; Zhang, T. L.; Pope, S. A.

    2011-01-01

    Typically multi-spacecraft missions are ideally suited to the study of shock spatial scales due to the separation of temporal and spatial variations. These missions are not possible at all locations and therefore in-situ multi-spacecraft measurements are not available beyond the Earth. The present paper presents a study of shock spatial scales using single spacecraft measurements made by the Venus Express spacecraft. The scales are determined based on previous knowledge of s...

  19. Planetary nebulae with UVIT: Far ultra-violet halo around the Bow Tie nebula (NGC 40)

    Science.gov (United States)

    Kameswara Rao, N.; Sutaria, F.; Murthy, J.; Krishna, S.; Mohan, R.; Ray, A.

    2018-01-01

    Context. NGC 40 is a planetary nebula with diffuse X-ray emission, suggesting an interaction of the high-speed wind from WC8 central star (CS) with the nebula. It shows strong C IV 1550 Å emission that cannot be explained by thermal processes alone. We present here the first map of this nebula in C IV emission using broad band filters on the Ultra-Violet Imaging Telescope (UVIT). Aim. We aim to map the hot C IV-emitting gas and its correspondence with soft X-ray (0.3-8 keV) emitting regions in order to study the shock interaction between the nebula and the ISM. We also aim to illustrate the potential of UVIT for nebular studies. Methods: We carry out a morphological study of images of the nebula obtained at an angular resolution of about 1.3″ in four UVIT filter bands that include C IV 1550 Å and [C II] 2326 Å lines as well as UV continuum. We also make comparisons with X-ray, optical, and IR images from the literature. Results: The [C II] 2326 Å images show the core of the nebula with two lobes on either side of CS similar to [N II]. The C IV emission in the core shows similar morphology and extent to that of diffuse X-ray emission concentrated in nebular condensations. A surprising UVIT discovery is the presence of a large faint far UV (FUV) halo in an FUV filter with λeff of 1608 Å. The UV halo is not present in any other UV filter. The FUV halo is most likely due to UV fluorescence emission from the Lyman bands of H2 molecules. Unlike the optical and IR halo, the FUV halo trails predominantly towards the south-east side of the nebular core, opposite to the CS's proper motion direction. Conclusions: Morphological similarity of C IV 1550 Å and X-ray emission in the core suggests that it results mostly from the interaction of strong CS wind with the nebula. The FUV halo in NGC 40 highlights the extensive existence of H2 molecules in the regions even beyond the optical and IR halos. Thus UV studies are important to estimate the amount of H2, which is probably the most dominant molecule and significant for mass-loss studies. Based on data obtained with the Ultra-Violet Imaging Telescope (UVIT) on the ASTROSAT satellite.

  20. Orthopedic cervical headgear with an expanded inner bow in class II correction

    National Research Council Canada - National Science Library

    Kirjavainen, M; Kirjavainen, T; Hurmerinta, K; Haavikko, K

    2000-01-01

    Forty consecutively referred children, 20 boys and 20 girls, with a Class II division I malocclusion and protrusive maxilla were treated with orthopedic cervical headgear with a 10 mm expanded inner...

  1. Optical properties of InAlGaAs quantum wells: Influence of segregation and band bowing

    DEFF Research Database (Denmark)

    Jensen, Jacob Riis; Hvam, Jørn Märcher; Langbein, Wolfgang

    1999-01-01

    Knowledge of the quaternary InAlGaAs material system is very limited for the composition range relevant for growth on GaAs substrates. We report on the characterization and modeling of InAlGaAs quantum wells with AlGaAs barriers, grown pseudomorphically on a GaAs substrate with molecular beam...... epitaxy. The quantum wells are characterized with photoluminescence, and the measured transition energies are modeled taking into account the influence of In segregation on the shape of the well potential. From the modeling we deduce a relation for the low temperature band gap of unstrained Inx(AlyGa1 – y...

  2. A discussion of the depositional environment and silica sources of the novaculite in Broken Bow, Oklahoma

    Energy Technology Data Exchange (ETDEWEB)

    Dubois, P.F. (Washington Univ., St. Louis, MO (United States). Earth and Planetary Sciences Dept.)

    1993-03-01

    There has been considerable research and speculation concerning the depositional environment for the silica sources of the Arkansas Novaculite in the Ouachita Mountains. Arkansas Novaculite conformably overlies Missouri Mountain Shale and underlies the Mississippian Stanley Shale group. Structural evidence in the Ouachita's supports a continent-continent collision and/or island arc subduction involving the continental margin of North America during Late Mississippian, after the novaculite sequence (Thomas, 1989, Appalachian-Ouachita orogen beneath the eastern gulf coastal plain, DNAG F-2). When considering the amount of silica required for deposition of massive and relatively pure silica-rich novaculite, the following were taken into account: (1) the source of the silica, (2) what environment will support silica-based marine life, and (3) what environmental conditions would account for thick, clean silica beds. Great quantities of silica most likely came from several sources. Structural evidence supports sources from the suspect Ouachita wedge and volcanic ash. Abundant fossil evidence suggests that a large portion of the silica source can be attributed to marine life such as radiolaria and sponge spicules. Though the role of metamorphic activity could be key in the formation of these novaculites, correlation of structural and sedimentary depositional features, and fossil evidence overwhelmingly indicate a marine environment for the silica source. The predisposition of radiolaria for an open ocean environment, the conodonts' restricted ranges, the preference of most siliceous sponges for a deep ocean environment, and the lack of stratigraphic evidence pointing to a shallowing of the seas, suggest that the Arkansas-Oklahoma novaculites from deep-marine radiolaria deposits with additional deposition from sedimentary sources.

  3. Effects of highways on grizzly bear movement in the Bow River Watershed, Alberta, Canada

    OpenAIRE

    Gibeau, Michael L.; Clevenger, Anthony P.; Herrero, Stephen; Wierzchowski, Jack

    2001-01-01

    Previous research on response by grizzly bears to roads has been confined to interactions with tertiary or unimproved road systems. To our knowledge no information exists to evaluate the potential of high-speed, high-volume highways to disrupt or prevent grizzly bear movement. We know of no other area within occupied grizzly bear habitat in North America that has such an extensive network of high-speed, high-volume highways. Between 1994 and 1998 we captured and radio-marked grizzly bears in ...

  4. The Fruits of Adversity: Technical Refinements of the Turkish Composite Bow during the Crusading Era

    Science.gov (United States)

    1991-01-01

    bringing spectacular victories against the Franks and Mongols in the latter half of the century. Because the institution of using mamluks was so vital a...safeguarded the "nomadic vitality " and the zealousness of a new convert to Islam.27 To ensure the exclusiveness of this class of military troop, a...post tergum sine intermissione in persequentes immittentes sagittas." Itinerarium peregrinorum, p. 118, cited in Smail, p. 162. 24Eventhough the Turkic

  5. Turning the knots in your stomach into bows: Reappraising arousal improves performance on the GRE

    Science.gov (United States)

    Jamieson, Jeremy P.; Mendes, Wendy Berry; Blackstock, Erin; Schmader, Toni

    2009-01-01

    This research examined the benefits of interpreting physiological arousal as a challenge response on practice and actual Graduate Record Examination (GRE) scores. Participants who were preparing to take the GRE reported to the laboratory for a practice GRE study. Participants assigned to a reappraisal condition were told arousal improves performance, whereas control participants were not given this information. We collected saliva samples at baseline and after the appraisal manipulation, which were then assayed for salivary alpha amylase (sAA), a measure of sympathetic nervous system activation. Reappraisal participants exhibited a significant increase in sAA and outperformed controls on the GRE-math section. One to three months later, participants returned to the lab and provided their score reports from their actual GRE. Again, reappraisal participants scored higher than controls on the GRE-math section. These findings illuminate the powerful influence appraisal has on physiology and performance both in and out of the laboratory. PMID:20161454

  6. Large Scale Earth's Bow Shock with Northern IMF as Simulated by ...

    Indian Academy of Sciences (India)

    Despite the large cell size of the current version of the PIC code, it is powerful to retain macrostructure of planets magnetospheres in very short time, thus it can be used for pedagogical test purposes. It is also likely complementary with MHD to deepen our understanding of the large scale magnetosphere.

  7. Comparison of upper limb muscles behaviour for skilled and recreational archers using compound bow

    Science.gov (United States)

    Ariffin, Muhammad Shahimi; Rambely, Azmin Sham

    2017-04-01

    The purpose of this study was to investigate muscles activity during archery by carrying out an electromyography (EMG) experiment towards 12 muscles and six joints involving two types of subject (skilled and recreational). EMG is used to detect muscle signals during any particular activity. There were two types of data recorded which were maximum voluntary contraction (MVC) and archery activity. The skilled archer was found to produce 280 N of biceps brachii, 213.9 N of the deltoid, 123.4 N of trapezius forces compare to that of the recreational archer with 371.1 N, 164.9 N and 163.8 N, respectively for the draw arm during drawing phase. It is concluded that the recreational archer tends to a muscle fatigue phenomenon thus may contribute to possible serious injuries.

  8. 'You have to bow right here': heteronormative scripts and intimate partner violence in women's same-sex relationships.

    Science.gov (United States)

    Sanger, Nadia; Lynch, Ingrid

    2017-06-28

    Intimate partner violence is increasingly recognised as occurring not only between heterosexual partners but also in same-sex relationships. Heterogendered relationship norms have been identified as intersecting with other social inequalities to create and sustain power differentials between partners - and fuel violence - yet remain largely unexplored in relation to women's same-sex relationships. Building on existing feminist research we explore the use of gendered scripts in South African lesbian and bisexual women's accounts of relationship norms and practices. We apply a feminist poststructuralist lens to focus-group discussion data to investigate how such scripts are drawn on to either uphold or challenge violent and coercive relationship practices. The findings illustrate the salience of heterogendered norms and demonstrate how violent practices become possible in contexts of deepening socioeconomic impoverishment - such as in post-apartheid South Africa - where race, space, gender and sexuality are tied to attempts at reclaiming respectable personhood. Efforts to dismantle inequitable gendered power relations and attendant violent practices require both macro-interventions aimed at shifting structural constraints on lesbian and bisexual women's agency, as well as micro-processes aimed at scripting equal power relations between partners as desirable.

  9. 78 FR 56650 - Medicine Bow-Routt National Forests and Thunder Basin National Grassland; Wyoming; Thunder Basin...

    Science.gov (United States)

    2013-09-13

    ... predator control in prairie dog colonies); and use of physical barriers (e.g., fencing and vegetative barriers). The Forest Service also proposes to make the following minor modifications to the 2009 Prairie... National Guard Armory--315 Pearson Road. October 8: Newcastle, Wyoming--USDA Hell Canyon Ranger District...

  10. Anti-slamming bulbous bow and tunnel stern applications on a novel Deep-V catamaran for improved performance

    OpenAIRE

    Mehmet Atlar; Kwangcheol Seo; Roderick Sampson; Devrim Bulent Danisman

    2013-01-01

    While displacement type Deep-V mono hulls have superior seakeeping behaviour at speed, catamarans typically have modest behaviour in rough seas. It is therefore a logical progression to combine the superior seakeeping performance of a displacement type Deep-V mono-hull with the high-speed benefits of a catamaran to take the advantages of both hull forms. The displacement Deep-V catamaran concept was developed in Newcastle University and Newcastle University's own multi-purpose research vessel...

  11. 75 FR 74678 - Medicine Bow-Routt National Forests and Thunder Basin National Grassland; Colorado and Wyoming...

    Science.gov (United States)

    2010-12-01

    ... MBRTB. Purpose and Need for Action: The purpose and need of the project is to prevent and reduce loss of... condition and biodiversity of the MBRTB by preventing or limiting the spread of aggressive, non-native plant... where effective ground application is not possible; and Maintain or improve protection measures for...

  12. Band gap bowing of nanocrystalline Zn(1-x)CaxO thin films for blue and ultraviolet optoelectronic applications

    Science.gov (United States)

    Narayanan, Nripasree; Deepak, N. K.

    2017-09-01

    Alloying materials having different band gaps is a tool to tailor the optical energy gaps of semiconducting materials. In the present study, the effect of alloying ZnO with CaO was investigated. Thin films of Zn(1-x)CaxO (0 ≤ x ≤ 0.20) were deposited on glass substrates by spray pyrolysis technique. All the films possessed nanocrystalline grains and crystallinity deteriorated with increase in Ca2+ substitution level. Elemental composition analysis confirmed the presence of Ca in the samples. Films showed good optical transmission in the visible and near infrared region and the absorption edge blue-shifted with Ca2+ substitution. Optical energy gap enhanced by 9.89% upon 20% Ca2+ substitution. Photoluminescence analysis also confirmed band gap broadening with mesovalent cation substitution.

  13. Bow has its short, crossbow has its long 弓亦有所短 弩亦有所长

    DEFF Research Database (Denmark)

    wu, zheng; Dai, Zheng

    2009-01-01

    There are two kinds of designer can be hired for a project. They are freelancer designer or designer in company. From designer’s perspective, they would consider about several aspects. The big fame could not equal to a big team. Designer could finish a project individually. The standard of good...... a design is blurry. The work of design generates several times value than it cost. In a company, designers follow a formal process, the quality is guaranteed. Freelancer is more flexible, the result can be a higher level and out of the box. It is easier to adapt to different project, but with higher risk....... Combine freelancer designer and designer in company is necessary to an innovative project. Designers should have an ability to adapt themself in between of these two design organization....

  14. 76 FR 9320 - Foreign-Trade Zone 274-Butte-Silver Bow, MT; Application for Manufacturing Authority REC Silicon...

    Science.gov (United States)

    2011-02-17

    ... Authority REC Silicon (Polysilicon and Silane Gas) Butte, MT An application has been submitted to the..., requesting manufacturing authority on behalf of REC Silicon, located in Butte, Montana. The application was... regulations of the Board (15 CFR part 400). It was formally filed on February 11, 2011. The REC Silicon...

  15. 75 FR 19936 - Medicine Bow-Routt National Forests, Brush Creek/Hayden Ranger District Saratoga, WY

    Science.gov (United States)

    2010-04-16

    ..., deadfall in beetle-kill areas has the potential to slow or prevent forest regeneration; negatively impact... products; promote forest regeneration; reduce hazard trees from high priority areas affecting public safety; improve recreational facilities and opportunities; improve wildlife habitat diversity; repair soil and...

  16. Steady-state Manoeuvring of a Generic ASD Tug in Escort Pull and Bow-rope Aided Push Operation

    Directory of Open Access Journals (Sweden)

    Jaroslaw Artyszuk

    2014-09-01

    Full Text Available This paper is devoted to expand the very promising research undertaken in the author's previous work, basically done on simplified modelling the escort push operation. Now, the other two modes of a tug's employment, as stated in the title, are covered. The special focus is again set on the indirect towing in that the towline force is much higher than the thruster force. The ratio of these two forces, referred to as the relative towing force (or amplification ratio is evaluated together with the hull drift angle and the thruster(-s angle for a given escort speed. This mutual relationship is known as the tug performance diagram. Although rather generic (container-type formulas are derived, they are supplied for exemplification purposes with simple, analytically given hull hydrodynamic forces. The aim is also here to provide a basis for further sensitivity analysis of the model and possible improvement/optimisation to the tug design. The obtained charts also could serve as rough and clear guidance for towmasters while escorting.

  17. A new rectenna circuit using a bow-tie antenna for the conversion of microwave power to dc power

    Science.gov (United States)

    Tran, Michael; Nguyen, Cam

    1993-01-01

    The novel rectenna circuit presented, which integrated a bowtie antenna with a diode, is capable of broadband, high-efficiency operation, and is insensitive to incident field angle. The device is noted, moreover, to behave as a lowpass filter for dc output. For 2.45 GHz operation, a 79-percent conversion efficiency has been demonstrated.

  18. A dynamics of the trainings loadings of highly skilled shooters is from a bow in precompetytion middle cycle

    Directory of Open Access Journals (Sweden)

    Briskin Yu.A.

    2010-08-01

    Full Text Available Quantity indicators of shots of sportsmen in building blocks of a mesocycle are defined. The qualifying determined dynamic of volumes of training loads of sportsmen fixed. Research was conducted with the participation 16 sportsmen of a combined team of Ukraine. The precompetitive mesocycle powered up 3 microcycle (2 failing and 1 regenerative. Duration of 2 first microcycle constituted 5 days (4 training and 1 assigned for "repose" and the third - one training day. It fixed, that the volume of a training load has undulating positive dynamic from the beginning before his completion. Correlations of qualification of sportsmen and volumes of a training load (r = 0,39-0,63 in different building blocks of a mesocycle fixed.

  19. Twin studies of schizophrenia: from bow-and-arrow concordances to star wars Mx and functional genomics.

    Science.gov (United States)

    Cardno, A G; Gottesman, I I

    2000-01-01

    Twin studies have been vital for establishing an important genetic contribution to the etiology of schizophrenia. The five newest studies since 1995 from Europe and Japan have confirmed earlier findings. They yielded probandwise concordance rates of 41-65% in monozygotic (MZ) pairs and 0-28% in dizygotic (DZ) pairs, and heritability estimates of approximately 80-85%. Twin studies are also valuable for investigating the etiological relationships between schizophrenia and other disorders, and the genetic basis of clinical heterogeneity within schizophrenia. Studies of discordant MZ pairs provide further insights into non-inherited factors that contribute to the multifactorial etiology of this disorder. More recently, twin studies have begun to be used to directly investigate molecular genetic and epigenetic processes underlying schizophrenia. Copyright 2000 Wiley-Liss, Inc.

  20. Arsenic Removal from Drinking Water by Adsorptive Media USEPA Demonstration Project at Bow, NH Final performance Evaluation Report

    Science.gov (United States)

    This report documents the activities performed during and the results obtained from the U.S. Environmental Protection Agency (EPA) arsenic removal treatment technology demonstration project at the White Rock Water Company (WRWC) public water system, a small residential drinking w...

  1. Bow Ties in the Sky. II. Searching for Gamma-Ray Halos in the Fermi Sky Using Anisotropy

    Science.gov (United States)

    Tiede, Paul; Broderick, Avery E.; Shalaby, Mohamad; Pfrommer, Christoph; Puchwein, Ewald; Chang, Philip; Lamberts, Astrid

    2017-12-01

    Many-degree-scale gamma-ray halos are expected to surround extragalactic high-energy gamma-ray sources. These arise from the inverse Compton emission of an intergalactic population of relativistic electron/positron pairs generated by the annihilation of ≳ 100 {GeV} gamma rays on the extragalactic background light. These are typically anisotropic due to the jetted structure from which they originate (in the case of radio galaxies) or are oriented perpendicular to a large-scale intergalactic magnetic field (for blazar geometries). Here, we propose a novel method for detecting these inverse Compton gamma-ray halos based on this anisotropic structure that is centered on the active galactic nucleus (AGN). By marginalizing over the radial distribution of halo photons, we demonstrate that the angular power spectrum shows a characteristic sawtooth pattern with a dominant dipolar power and elevated even multipoles. Specifically, we show that by stacking those angular power spectra instead of images, it is possible to robustly detect gamma-ray halos with existing Fermi Large Area Telescope (LAT) observations for a broad class of intergalactic magnetic fields. Importantly, by testing a large number of systematics, our suggested power spectrum statistics appears to be robust and unbiased with respect to systematic uncertainties within the LAT instrumental response and associated with contaminating astronomical sources.

  2. Disturbance history of the Medicine Bow Range, Wyoming, using historical documents, contemporary forest inventory, and lake sediment cores

    Science.gov (United States)

    V. Carter; A. Brunelle; J. Shaw

    2014-01-01

    In the late 1860s, Euro-American settlement and related activities, including logging, began affecting the composition and structure of forests of the western United States. These impacts were likely to be most substantial along the corridor of the trans-continental railroad. Construction and maintenance of the railroad created a high dependence for wood, especially...

  3. Quantification of cephalomedullary nail fit in the femur using 3D computer modelling: a comparison between 1.0 and 1.5m bow designs.

    Science.gov (United States)

    Schmutz, Beat; Amarathunga, Jayani; Kmiec, Stanley; Yarlagadda, Prasad; Schuetz, Michael

    2016-04-27

    The radius of curvature (ROC) misfit of cephalomedullary nails during anterograde nailing can lead to complications such as distal anterior cortical encroachment. This study quantified the anatomical fit of a new nail with 1.0-m ROC (TFN-ADVANCED(™) Proximal Femoral Nailing System [TFNA]) compared with a nail with 1.5-m ROC (Gamma3 Long Nail R1.5 [Gamma3]). We generated 63 three-dimensional models (48 female, 45 right femur) representing the cortical surfaces of the femora (31 Caucasian, 28 Japanese, and 4 Thai). The mean age of the specimens was 77 years (±8.1), and the mean height was 158.5 cm (±9.6). Utilizing a customized software tool, nail fit was determined from the total surface area of nail protrusion from the inner cortex surface and maximum distance of nail protrusion in the axial plane; the position of the distal nail tip within the canal was also determined. Overall, TFNA had both a significantly smaller mean total surface area of nail protrusion (915.8 vs. 1181.6 mm(2); P < 0.05) and a mean maximum distance of nail protrusion in the axial plane (1.9 vs. 2.1 mm; P = 0.007) when compared with Gamma3. The mean total surface area of nail protrusion was significantly smaller with TFNA versus Gamma3 in both the Caucasian (P = 0.0009) and Asian (Japanese and Thai) samples (P = 0.000002); the mean maximum distance of TFNA protrusion was significantly smaller in Asians (P = 0.04), but not in Caucasians (P = 0.08). Most tip positions for both nail types were anterior, but TFNA had a higher number of center positions than Gamma3 (13 vs. 7) and a shift from the far anterior cortex to the center of the medullary canal (overall and in Caucasians). In Asians, the most prominent position was far anterior for both nails. The 1.0-m ROC TFNA nail resulted in better fit than the 1.5-m ROC Gamma3 nail. Clinical trials and case studies should be conducted in the future to verify if these findings would also result in clinical improvements.

  4. Weapons in the 10–11th century Carpathian Basin. Studies in weapon technology and methodology – rigid bow applications and southern import swords in the archaeological material

    Directory of Open Access Journals (Sweden)

    Ádám Bíró

    2015-02-01

    Full Text Available Abstract of PhD thesis submitted in 2014 to the Archaeology Doctoral Programme, DoctoralSchool of History, Eötvös Loránd University, Budapest under the supervision of Tivadar Vida.

  5. Bow Your Head in Shame, or, Hold Your Head Up with Pride: Semantic Processing of Self-Esteem Concepts Orients Attention Vertically.

    Directory of Open Access Journals (Sweden)

    J Eric T Taylor

    Full Text Available Embodied cognition holds that abstract concepts are grounded in perceptual-motor simulations. If a given embodied metaphor maps onto a spatial representation, then thinking of that concept should bias the allocation of attention. In this study, we used positive and negative self-esteem words to examine two properties of conceptual cueing. First, we tested the orientation-specificity hypothesis, which predicts that conceptual cues should selectively activate certain spatial axes (in this case, valenced self-esteem concepts should activate vertical space, instead of any spatial continuum. Second, we tested whether conceptual cueing requires semantic processing, or if it can be achieved with shallow visual processing of the cue words. Participants viewed centrally presented words consisting of high or low self-esteem traits (e.g., brave, timid before detecting a target above or below the cue in the vertical condition, or on the left or right of the word in the horizontal condition. Participants were faster to detect targets when their location was compatible with the valence of the word cues, but only in the vertical condition. Moreover, this effect was observed when participants processed the semantics of the word, but not when processing its orthography. The results show that conceptual cueing by spatial metaphors is orientation-specific, and that an explicit consideration of the word cues' semantics is required for conceptual cueing to occur.

  6. Bow Your Head in Shame, or, Hold Your Head Up with Pride: Semantic Processing of Self-Esteem Concepts Orients Attention Vertically.

    Science.gov (United States)

    Taylor, J Eric T; Lam, Timothy K; Chasteen, Alison L; Pratt, Jay

    2015-01-01

    Embodied cognition holds that abstract concepts are grounded in perceptual-motor simulations. If a given embodied metaphor maps onto a spatial representation, then thinking of that concept should bias the allocation of attention. In this study, we used positive and negative self-esteem words to examine two properties of conceptual cueing. First, we tested the orientation-specificity hypothesis, which predicts that conceptual cues should selectively activate certain spatial axes (in this case, valenced self-esteem concepts should activate vertical space), instead of any spatial continuum. Second, we tested whether conceptual cueing requires semantic processing, or if it can be achieved with shallow visual processing of the cue words. Participants viewed centrally presented words consisting of high or low self-esteem traits (e.g., brave, timid) before detecting a target above or below the cue in the vertical condition, or on the left or right of the word in the horizontal condition. Participants were faster to detect targets when their location was compatible with the valence of the word cues, but only in the vertical condition. Moreover, this effect was observed when participants processed the semantics of the word, but not when processing its orthography. The results show that conceptual cueing by spatial metaphors is orientation-specific, and that an explicit consideration of the word cues' semantics is required for conceptual cueing to occur.

  7. Multi‐instrument observations from Svalbard of a traveling convection vortex, electromagnetic ion cyclotron wave burst, and proton precipitation associated with a bow shock instability

    DEFF Research Database (Denmark)

    Engebretson, M. J.; Yeoman, T. K.; Oksavik, K.

    2013-01-01

    An isolated burst of 0.35 Hz electromagnetic ion cyclotron (EMIC) waves was observed at four sites on Svalbard from 0947 to 0954 UT 2 January 2011, roughly 1 h after local noon. This burst was associated with one of a series of ~50 nT magnetic impulses observed at the northernmost stations......-based observations of the Hα line at Longyearbyen indicated proton precipitation at the same time as the EMIC wave burst, and NOAA-19, which passed over the west coast of Svalbard between 0951 and 0952, observed a clear enhancement of ring current protons at the same latitude. Electron precipitation from this same...... satellite indicated that the EMIC burst was located on closed field lines, but near to the polar cap boundary. We believe these are the first simultaneous observations of EMIC waves and precipitating energetic protons so near to the boundary of the dayside magnetosphere. Although several spacecraft upstream...

  8. ARSENIC REMOVAL FROM DRINKING WATER BY ADSORPTIVE MEDIA. U.S. EPA DEMONSTRATION PROJECT AT BOW, NH , SIX MONTH EVALUATION REPORT

    Science.gov (United States)

    This report documents the activities performed during and the results obtained from the first six months of the arsenic removal treatment technology demonstration project at the White Rock Water Company (WRWC) public water system, a small residential drinking water facility in Bo...

  9. "It's Just Like an Extra String to Your Bow": Exploring Higher Education Students' Perceptions and Experiences of Extracurricular Activity and Employability

    Science.gov (United States)

    Thompson, Leanne J.; Clark, Gordon; Walker, Marion; Whyatt, J. Duncan

    2013-01-01

    Students' experience of higher education comprises not only their academic studies but also their extracurricular activities. This article reports on the findings from a mixed-methods research project, exploring in detail the nature and value of extracurricular activity engagement and the significance of institutional schemes encouraging…

  10. 33 CFR 207.440 - St. Marys Falls Canal and Locks, Mich.; use, administration, and navigation.

    Science.gov (United States)

    2010-07-01

    ...) Vessels with non-friction winches or lack of both bow and stern thrusters. Four vessel-supplied line... bow/stern thrusters. Bow and/or stern thruster use shall be kept to a minimum while transiting the Soo... with bow or stern thrusters, may cause control difficulties for certain classes of vessels. Therefore...

  11. 33 CFR 401.6 - Markings.

    Science.gov (United States)

    2010-07-01

    ... both sides at the bow and stern. (b) In addition to the markings required by paragraph (a) of this... markings. (c) Where a vessel's bulbous bow extends forward beyond her stem head, a symbol of a bulbous bow... number indicating the total length in meters by which the bulbous bow projects beyond the stem. (68 Stat...

  12. Relações interpessoais na escola: uma trama de muitos fios, poucos laços e alguns nós/Interpersonal relations in the school: a tram of many wires, few bows and some knot

    Directory of Open Access Journals (Sweden)

    Adriana Stella Pierini

    2006-01-01

    Full Text Available A partir do olhar de uma profissional de educação que, atualmente, ocupa o lugar de orientadora pedagógica de uma escola pública municipal de educação fundamental, este artigo busca relatar um determinado percurso vivenciado por um subgrupo de profissionais na escola, evidenciando um diálogo reflexivo entre as práticas cotidianas e as relações interpessoais no espaço escolar. Desta forma, reflete o exercício de produção de conhecimento e pesquisa na escola e aborda, fundamentalmente, a importância do grupo na constituição do sujeito que, ao fazer emergir questões do seu cotidiano, direciona seu estudo, tendo como foco alguns elementos: a reflexão sobre o conceito de aula a partir da discussão sobre projetos e outras atividades escolares, a humanização das relações, os diversos tempos escolares e os vínculos que aí se constituem, os entraves pessoais e institucionais na transformação dos tempos regulamentados em tempos de convívio, e a importância da teoria na (re elaboração de conceitos, com base na afirmação de que o desenvolvimento do indivíduo não depende apenas do aspecto orgânico, mas principalmente, da qualidade das interações que mantém com o meio em que vive.With the point of view from a education professional that, actually, occupies the place of pedagogical guide of a municipal public school of primary education, this article intends to report a determinate course lived by a subgroup of professionals at the school, evidencing a reflexive dialog between quotidian practices and interpersonal relations at the school space. This way, reflects the knowledge production and research exercise at the school and approaching, fundamentally, the group importance in the subject constitution that, at the time he makes emerge questions about his quotidian, directs its study having as focus the following elements: the reflection about the class concept beginning with the discussion projects and other school activities, the humanization of relations, the diverse school times and the connections made since then, the personal and institutional difficulties in the transformation of the ruled times into sociability times and the importance of theory in the concept (re elaboration, based on the affirmation that subject development depend not only of the organic appearance, but mainly of the quality of the interaction that sustain the media in which he lives.

  13. Three-dimensional Features of the Outer Heliosphere Due to Coupling between the Interstellar and Heliospheric Magnetic Field. V. The Bow Wave, Heliospheric Boundary Layer, Instabilities, and Magnetic Reconnection

    Science.gov (United States)

    Pogorelov, N. V.; Heerikhuisen, J.; Roytershteyn, V.; Burlaga, L. F.; Gurnett, D. A.; Kurth, W. S.

    2017-08-01

    The heliosphere is formed due to interaction between the solar wind (SW) and local interstellar medium (LISM). The shape and position of the heliospheric boundary, the heliopause, in space depend on the parameters of interacting plasma flows. The interplay between the asymmetrizing effect of the interstellar magnetic field and charge exchange between ions and neutral atoms plays an important role in the SW-LISM interaction. By performing three-dimensional, MHD plasma/kinetic neutral atom simulations, we determine the width of the outer heliosheath—the LISM plasma region affected by the presence of the heliosphere—and analyze quantitatively the distributions in front of the heliopause. It is shown that charge exchange modifies the LISM plasma to such extent that the contribution of a shock transition to the total variation of plasma parameters becomes small even if the LISM velocity exceeds the fast magnetosonic speed in the unperturbed medium. By performing adaptive mesh refinement simulations, we show that a distinct boundary layer of decreased plasma density and enhanced magnetic field should be observed on the interstellar side of the heliopause. We show that this behavior is in agreement with the plasma oscillations of increasing frequency observed by the plasma wave instrument onboard Voyager 1. We also demonstrate that Voyager observations in the inner heliosheath between the heliospheric termination shock and the heliopause are consistent with dissipation of the heliospheric magnetic field. The choice of LISM parameters in this analysis is based on the simulations that fit observations of energetic neutral atoms performed by Interstellar Boundary Explorer.

  14. Technical assistance to the Montana Department of Health and Environmental Sciences. Arsenic and lead exposure study of residents living near the Rocker operable unit of the Silver Bow Creek Superfund site, Rocker, Montana. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Gaventa, S.; Coull, B.; Gedrose, J.; Jones, P.; Dennehy, D.

    1992-01-01

    The ATSDR and the Montana Department of Health and Environmental Sciences conducted a study to assess arsenic and lead exposure among residents of Rocker, Montana, where arsenic had been detected in soil up to 214,000 ppm. No statistically significant difference was found between Rocker residents and a comparison population with respect to the geometric mean of the urine arsenic levels. When data were combined from both groups, recent seafood ingestion was the variable most strongly associated with detectable urine arsenic levels. Although blood lead levels in the target area differed significantly from those in the comparison, a significant association was not detected between blood lead levels > or = 10 microgram/d1 and area of residence. Lead was detected in the blood of two siblings in the target area at levels of 20.7 and 31.3 microgram/d1. A lead based paint hazard and elevated concentrations of soil lead from the children's play area were detected in the household.

  15. Observing Arctic Sea Ice from Bow to Screen: Introducing Ice Watch, the Data Network of Near Real-Time and Historic Observations from the Arctic Shipborne Sea Ice Standardization Tool (ASSIST)

    Science.gov (United States)

    Orlich, A.; Hutchings, J. K.; Green, T. M.

    2013-12-01

    The Ice Watch Program is an open source forum to access in situ Arctic sea ice conditions. It provides the research community and additional stakeholders a convenient resource to monitor sea ice and its role in understanding the Arctic as a system by implementing a standardized observation protocol and hosting a multi-service data portal. International vessels use the Arctic Shipborne Sea Ice Standardization Tool (ASSIST) software to report near-real time sea ice conditions while underway. Essential observations of total ice concentration, distribution of multi-year ice and other ice types, as well as their respective stage of melt are reported. These current and historic sea ice conditions are visualized on interactive maps and in a variety of statistical analyses, and with all data sets available to download for further investigation. The summer of 2012 was the debut of the ASSIST software and the Ice Watch campaign, with research vessels from six nations reporting from a wide spatio-temporal scale spanning from the Beaufort Sea, across the North Pole and Arctic Basin, the coast of Greenland and into the Kara and Barents Seas during mid-season melt and into the first stages of freeze-up. The 2013 summer field season sustained the observation and data archiving record, with participation from some of the same cruises as well as other geographic and seasonal realms covered by new users. These results are presented to illustrate the evolution of the program, increased participation and critical statistics of ice regime change and record of melt and freeze processes revealed by the data. As an ongoing effort, Ice Watch/ASSIST aims to standardize observations of Arctic-specific sea ice features and conditions while utilizing nomenclature and coding based on the World Meteorological Organization (WMO) standards and the Antarctic Sea Ice and Processes & Climate (ASPeCt) protocol. Instigated by members of the CliC Sea Ice Working Group, the program has evolved with coordination from the International Arctic Research Center, software development by the Geographic Information Network of Alaska, and funding support from the Japanese Aerospace Exploration Agency (JAXA), the Japan Agency for Marine-Earth Science & Technology (JAMSTEC), and the National Science Foundation (NSF).

  16. The Frequency of Growing Season Frost in the Subalpine Environment (Medicine Bow Mountains, Southeastern Wyoming), The Interaction of Leaf Morphology and Infrared Radiational Cooling and the Effects of Freezing on Native Vegetation

    Science.gov (United States)

    1995-05-01

    majority of chilling stress studies have focused on crop plants of tropical or subtropical origin (Öquist and Wass 1988; Peeler and Naylor 1988...light energy. Plant Physiol 84:218-224 Eastham J and Rose CW 1988. Pasture evapotranspiration under varying tree planting density in an agroforestry ...fluorescence and photoinhibition in a tropical rainforest understory plant. Photosyn Res 27:135-142 Leuning R 1988. Leaf temperatures during radiation

  17. 78 FR 26614 - Narrow Woven Ribbon With Woven Selvedge From the People's Republic of China: Rescission of...

    Science.gov (United States)

    2013-05-07

    ... & Bow (Canada), Intercontinental Skyline, Multicolor, Supreme Laces Inc., Yama Ribbons, and Bows Co..., through August 31, 2012. Assessment The Department will instruct U.S. Customs and Border Protection (``CBP...

  18. 33 CFR 110.216 - Pacific Ocean at Santa Catalina Island, Calif.

    Science.gov (United States)

    2010-07-01

    ... place are prohibited. (4) The instructions of the Captain of the Port requiring vessels to anchor bow and stern, or with two bow anchors, or requiring shifting the anchorage of any vessel within the...

  19. 33 CFR 207.9 - Mystic River, Mass.; dam of Commonwealth of Massachusetts, Metropolitan District Commission.

    Science.gov (United States)

    2010-07-01

    ... accurately and distinctly marked at bow and stern showing the exact draft of water at such portions of the... for this purpose. (6) Equipment of each craft shall include a sufficient bow line and stern line. (j...

  20. 46 CFR 160.056-3 - Fittings and equipment.

    Science.gov (United States)

    2010-10-01

    ... fitting suitable for attaching a painter shall be fitted to the bow and stern. (b) Equipment. (1) The... attached to the bow and to the stern fittings. Each shall be of suitable material, at least 3/8-inch in...

  1. 33 CFR 165.150 - New Haven Harbor, Quinnipiac River, Mill River.

    Science.gov (United States)

    2010-07-01

    ... bridge is greater than twenty knots, and (iii) With the barge being towed on a hawser, stern first. (4..., bow first, with a second tug standing by to assist at the bow. (7) Nothing in this section is intended...

  2. 33 CFR 207.300 - Ohio River, Mississippi River above Cairo, Ill., and their tributaries; use, administration, and...

    Science.gov (United States)

    2010-07-01

    ... with bow and stern lines leading in opposite directions to prevent the vessel from “running” in the... of their bow waves and propeller washes on river banks; submerged or partially submerged structures...

  3. 33 CFR 207.10 - Charles River, Mass.; dam of Charles River Basin Commission.

    Science.gov (United States)

    2010-07-01

    ... accurately and distinctly marked at the bow and stern, showing the exact draft of water at such portions of... propellers on entering the lock after the bow of the vessel has entered, but will be drawn in by means of...

  4. A Projectile Motion Bullseye.

    Science.gov (United States)

    Lamb, William G.

    1985-01-01

    Explains a projectile motion experiment involving a bow and arrow. Procedures to measure "muzzle" velocity, bow elastic potential energy, range, flight time, wind resistance, and masses are considered. (DH)

  5. 77 FR 12323 - Draft Environmental Impact Statement for the General Management Plan, Buck Island Reef National...

    Science.gov (United States)

    2012-02-29

    ... anchoring for vessels at designated locations. No bow and stern anchoring would be permitted under this... Island for up to 72 vessels. Alternative C: This alternative provides for bow and stern anchoring and new... exception that shoreline bow and stern anchoring would be eliminated. Access to Buck Island would be...

  6. 33 CFR 207.275 - McClellan-Kerr Arkansas River navigation system: use, administration, and navigation.

    Science.gov (United States)

    2010-07-01

    ... deckhand, or more if the lockmaster so directs, shall be stationed at the bow and stern of tows. These... tend the lines at the bow and stern of each section of a tow that transits a lock or moors to the river... lockmaster. Vessels shall be moored with bow and stern lines leading in opposite directions to prevent the...

  7. 14 CFR 25.529 - Hull and main float landing conditions.

    Science.gov (United States)

    2010-01-01

    ... float landing conditions. (a) Symmetrical step, bow, and stern landing. For symmetrical step, bow, and stern landings, the limit water reaction load factors are those computed under § 25.527. In addition— (1.... (b) Unsymmetrical landing for hull and single float seaplanes. Unsymmetrical step, bow, and stern...

  8. 46 CFR 67.123 - Name and hailing port marking requirements.

    Science.gov (United States)

    2010-10-01

    ... the port and starboard bow and the stern of the vessel. The hailing port of the vessel must be marked on some clearly visible exterior part of the stern of the vessel. (b) Vessels with square bow. For vessels having a square bow, the name of the vessel must be marked on some clearly visible exterior part...

  9. 76 FR 69957 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Science.gov (United States)

    2011-11-09

    .... Rotation can be augmented by the use of the fitted bow and stern thrusters. The hull has been reinforced... appeared to be lower at the bow and stern aspects than at the beam (Greene, 1987a). Most drilling sounds... lines. Turret mooring allows orientation of the vessel's bow into the prevailing ice drift direction to...

  10. 76 FR 43639 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Science.gov (United States)

    2011-07-21

    ... the use of both stern and bow thrusters required for dynamic positioning during coupling. These data...B. Sound levels during coupling operations were dominated by the periodic use of the bow and stern... bow thruster actions. The EBRV would require the use of thrusters for dynamic positioning during...

  11. 76 FR 68974 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Science.gov (United States)

    2011-11-07

    ... turret by hydraulic jacks. Rotation can be augmented by the use of the fitted bow and stern thrusters... levels appeared to be lower at the bow and stern aspects than at the beam (Greene, 1987a). Most drilling... fouling of the anchor lines. Turret mooring allows orientation of the vessel's bow into the prevailing ice...

  12. 14 CFR 23.529 - Hull and main float landing conditions.

    Science.gov (United States)

    2010-01-01

    ... Water Loads § 23.529 Hull and main float landing conditions. (a) Symmetrical step, bow, and stern landing. For symmetrical step, bow, and stern landings, the limit water reaction load factors are those.... Unsymmetrical step, bow, and stern landing conditions must be investigated. In addition— (1) The loading for...

  13. 75 FR 8923 - Reorganization of Foreign-Trade Zone 274 Under Alternative Site Framework; City and County of...

    Science.gov (United States)

    2010-02-26

    ... authority to reorganize under the ASF with a service area of Butte-Silver Bow County, Montana, within and... and County of Butte-Silver Bow, MT Pursuant to its authority under the Foreign-Trade Zones Act of June... of general-purpose zones; Whereas, the City and County of Butte-Silver Bow, Montana, grantee of...

  14. Research study of space plasma boundary processes

    Science.gov (United States)

    Greenstadt, E. W.; Taylor, W. W. L.

    1984-01-01

    Representation of the Earth's bow shock and magnetopause and their geometrically determined macrostructure was investigated. Computer graphic depictions of the global distributions of bow shock structures and elementary animation of the dynamics of those distributions in the changing solar wind were developed. The shock-foreshock boundary and subcritical bow shocks as observed by ISEE 1 and 2 are discussed.

  15. Fountain rainbows.

    Science.gov (United States)

    Gedzelman, Stanley David; Hernández-Andrés, Javier

    2008-12-01

    We present the first measurements of radiance spectra of rainbows. The bows on two sunny days (3 and 6 June 2008) were produced by the fountain in the Parque de las Ciencias, Granada, Spain, that consists of a rectangular perimeter of 40 spray nozzles. Optical thickness of the spray from each nozzle was approximately 0.5. Spectral purity of the primary bow was highest for orange and blue, reaching values of 23% and 7%, respectively, while skylight 90 degrees from the Sun had a color purity of 34% (on 6 June). The secondary bow had much lower color purity with red absent because the regions around the bows and in Alexander's dark band were pale blue. The narrow sickle shape of the chromaticity curves for the primary bows and the absence of supernumerary bows indicated that the drop radius was between 0.2 and 0.4 mm.

  16. The Hutchins-Schelleng Violin Octet After 50 Years

    Science.gov (United States)

    Burns, Kevin; Maybury, Mark

    Scientifically speaking, the Hutchins-Schelleng violin octet is the most interesting of all the bowed string instruments. We refer specifically to those instruments resulting from the first application of physics to the design of bowed string instruments, viz., the scientific resonance scaling process developed by John Schelleng to dimension the violin - certainly the most “successful” and mature bowed string instrument - to cover a 3½ octave range.

  17. Characteristics of Task-specific Tremor in String Instrument Players

    OpenAIRE

    Lee, André; Chadde, Mareike; Altenmüller, Eckart; Schoonderwaldt, Erwin

    2014-01-01

    Background In recent studies primary bowing tremor has been described; however, tremor frequency has never been quantitatively assessed. In addition to describing phenomenological aspects of tremor we thus aimed at assessing tremor frequency. Our hypothesis was that primary bowing tremor is similar to the phenomenological aspects and frequency of primary writing tremor. Methods We quantified primary bowing tremor in four violinists under two conditions: open strings and a G major scale. Data ...

  18. Tracing Lines for violin and cello | Fokkens | Journal of the Musical ...

    African Journals Online (AJOL)

    A three-movement work for violin and cello,Tracing Lines is typical of Robert Fokkens's work since 2004. Initially inspired by the famous Xhosa bow-player Madosini, Fokkens has developed a compositional language which brings together techniques drawn from traditional Xhosa bow music with features from a range of ...

  19. 75 FR 41808 - Narrow Woven Ribbons With Woven Selvedge From the People's Republic of China: Final Determination...

    Science.gov (United States)

    2010-07-19

    ... verified the information submitted by Yama for use in our final determination. We used standard... Determination, we found that the following companies demonstrated eligibility for separate-rate status: Beauty... Ribbons and Bows Co., Ltd.. Yama Ribbons and 0 Bows Co., Ltd. Beauty Horn Investment Limited.. Tianjin Sun...

  20. Models of the circumstellar medium of evolving, massive runaway stars moving through the Galactic plane

    NARCIS (Netherlands)

    Meyer, D.M.-A.; Mackey, J.; Langer, N.; Gvaramadze, V.V.; Mignone, A.; Izzard, R.G.; Kaper, L.

    2014-01-01

    At least 5 per cent of the massive stars are moving supersonically through the interstellar medium (ISM) and are expected to produce a stellar wind bow shock. We explore how the mass-loss and space velocity of massive runaway stars affect the morphology of their bow shocks. We run two-dimensional

  1. 77 FR 9624 - Narrow Woven Ribbons With Woven Selvedge From Taiwan: Rescission, in Part, of Antidumping Duty...

    Science.gov (United States)

    2012-02-17

    ... Imports; (10) Papillon Ribbon & Bow (Canada); (11) Shienq Huong Enterprise Co., Ltd.; and (12) Supreme... Imports; (9) Papillon Ribbon & Bow (Canada); (10) Shienq Huong Enterprise Co., Ltd.; and (11) Supreme... Department will instruct U.S. Customs and Border Protection (CBP) to assess antidumping duties on all...

  2. 50 CFR 27.43 - Weapons other than firearms.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Weapons other than firearms. 27.43 Section 27.43 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR... Weapons other than firearms. The use or possession of cross bows, bows and arrows, air guns, spears, gigs...

  3. 14 CFR 25.527 - Hull and main float load factors.

    Science.gov (United States)

    2010-01-01

    ...) For the step landing case EC28SE91.036 (2) For the bow and stern landing cases EC28SE91.037 (b) The... of the attachment of the floats to the seaplane, the factor K 1 may be reduced at the bow and stern...

  4. 46 CFR 69.109 - Under-deck tonnage.

    Science.gov (United States)

    2010-10-01

    ...) For a vessel having a square bow or stern and tonnage deck with camber, the effect of the camber on... yield area, except in vessels (such as barges) with an upright bow or stern. (2) The breadths of each...) If the tonnage deck runs in a continuous line from stem to stern, the line of the tonnage deck is the...

  5. 75 FR 53672 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Science.gov (United States)

    2010-09-01

    ... conditions included the use of both stern and bow thrusters required for dynamic positioning during coupling... use of the bow and stern thrusters and ranged from 160 to 170 dBL. Figures 1-1 and 1-2 of the NEG and...

  6. 46 CFR 199.176 - Markings on lifesaving appliances.

    Science.gov (United States)

    2010-10-01

    ... plainly marked as follows: (1) Each side of each lifeboat and rescue boat bow must be marked in block... marked on the stern of the vessel to meet the requirements of subpart 67.123 of this chapter. (2) The number of persons for which the boast is equipped must be clearly marked, preferably on the bow, in...

  7. 75 FR 42071 - Taking and Importing Marine Mammals; Operations of a Liquified Natural Gas Port Facility in...

    Science.gov (United States)

    2010-07-20

    ... dominated by the periodic use of the bow and stern thrusters and ranged from 160 to 170 dBL. Figures 1-1 and... to the buoy through a series of engine and bow thruster actions. The EBRV would require the use of...

  8. 33 CFR 207.20 - Cape Cod Canal, Mass.; use, administration, and navigation.

    Science.gov (United States)

    2010-07-01

    ... is equipped with a rudder or a ship shaped bow, one tow line may be used. All tow lines of hawsers... exceeding 200 feet in length will be required to have an additional tug on the stern to insure that the tow... loaded firearms, ammunition, projectile firing devices, bows and arrows, crossbows, and explosives of any...

  9. 46 CFR 199.175 - Survival craft and rescue boat equipment.

    Science.gov (United States)

    2010-10-01

    ... must be capable of being used at each entrance on either side or at the stern of the boat to enable... the bow of the lifeboat, ready for use. On lifeboats to be launched by free-fall launching, both painters must be stowed near the bow ready for use. (A) If the painter is of synthetic material, the...

  10. 14 CFR 23.527 - Hull and main float load factors.

    Science.gov (United States)

    2010-01-01

    ... computed in the following manner: (1) For the step landing case EC28SE91.004 (2) For the bow and stern... K1 may be reduced at the bow and stern to 0.8 of the value shown in figure 2 of appendix I of this...

  11. 75 FR 49759 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Science.gov (United States)

    2010-08-13

    ... mammals that approach the vessel from the side or stern in order to ride the bow wave or rub on the seismic streamers deployed from the stern (and near the airgun array) as some scientists consider this a... summarized later in this document, data that are now available imply that TTS is unlikely to occur unless bow...

  12. 49 CFR 176.415 - Permit requirements for Division 1.5, ammonium nitrates, and certain ammonium nitrate fertilizers.

    Science.gov (United States)

    2010-10-01

    ... vessel must be moored bow to seaward, and must be maintained in a mobile status during loading, unloading... wire towing hawsers, each having an eye splice, lowered to the water's edge, one at the bow and the other at the stern. [Amdt. 176-30, 55 FR 52706, Dec. 21, 1990, as amended at 56 FR 66282, Dec. 20, 1991...

  13. 46 CFR 131.855 - Lifeboats and rescue boats.

    Science.gov (United States)

    2010-10-01

    ... must be plainly marked or painted on each side of the bow of each lifeboat and rescue boat in block... port whose marking on the stern is required by § 67.123 of this chapter. (b) The following must be plainly marked or painted on each side of the bow of each lifeboat and rescue boat in block capital...

  14. 33 CFR 165.756 - Regulated Navigation Area; Savannah River, Georgia.

    Science.gov (United States)

    2010-07-01

    ...'s hull. Fire Wire means a length of wire rope or chain hung from the bow and stern of a vessel in... the waterline, both on the off-shore bow and quarter of the ship. LNG vessels equipped with waterline...

  15. 46 CFR 169.739 - Lifeboats.

    Science.gov (United States)

    2010-10-01

    ... its stern as required by § 67.15 of this chapter must be plainly marked or painted on each side of the bow of each lifeboat in letters not less than 3 inches high. (b) Each lifeboat must have its number plainly marked or painted on each side of the bow in figures not less than 3 inches high. The lifeboats on...

  16. Weismann-Netter-Stuhl syndrome: report of two cases and treatment.

    Science.gov (United States)

    Gupta, Pratyush; Mittal, Ravi; Mittal, Samarth; Shankar, Vivek

    2014-02-04

    Weismann-Netter-Stuhl syndrome is a rarely reported cause of bowed legs; hence a thorough clinical and radiological examination is needed for its diagnosis. In view of the paucity of reports guiding the treatment of the deformity, we propose a one-level/two-level osteotomy with intramedullary nail fixation as a treatment modality for the tibial bowing.

  17. Double Bass

    Science.gov (United States)

    Askenfelt, Anders

    The study of the acoustics of bowed instruments has for several reasons focused on the violin. A substantial amount of knowledge has been accumulated over the last century (see Hutchins 1975, 1976; Hutchins and Benade 1997). The violin is discussed in Chap. 13, while the cello is discussed in Chap. 14. The bow is discussed in Chap. 16.

  18. 75 FR 18195 - Combined Notice of Filings #1

    Science.gov (United States)

    2010-04-09

    ... received the following electric rate filings: Docket Numbers: ER10-374-001. Applicants: Medicine Bow Power Partners, LLC. Description: Withdrawal of Request for Waiver of Medicine Bow Power Partners, LLC. Filed Date: 03/26/2010. Accession Number: 20100326-5082. Comment Date: 5 p.m. Eastern Time on Friday, April...

  19. Complicated Congenital Dislocation of the Knee: A Case Report

    Directory of Open Access Journals (Sweden)

    Firooz Madadi

    2016-10-01

    Radiologic investigation revealed bilateral knee joint dislocation accompanied by severe anterior bowing of both tibia proximally and posterior bowing of both femur distally, demonstrating a complicated congenital knee dislocation. Two-staged open reduction with proximal tibial osteotomy was performed to align the reduced knee joints. The patient was completely independent in her daily activities after surgical correction.

  20. Collisionless electrostatic shocks

    DEFF Research Database (Denmark)

    Andersen, H.K.; Andersen, S.A.; Jensen, Vagn Orla

    1970-01-01

    An attempt was made in the laboratory to observe the standing collisionless electrostatic shocks in connection with the bow shock of the earth......An attempt was made in the laboratory to observe the standing collisionless electrostatic shocks in connection with the bow shock of the earth...

  1. 36 CFR 242.25 - Subsistence taking of fish, wildlife, and shellfish: general regulations.

    Science.gov (United States)

    2010-07-01

    ..., mountain goat, moose, musk ox, Dall sheep, wolf, and wolverine. Bow means a longbow, recurve bow, or..., ground squirrel, marmot, wolf, or wolverine. Fyke net means a fixed, funneling (fyke) device used to... may not use wildlife as food for a dog or furbearer, or as bait, except as allowed for in § 242.26...

  2. 50 CFR 32.35 - Kansas.

    Science.gov (United States)

    2010-10-01

    ... only allow waterfowl hunting by boat in Bow Creek. You may not create a wake while in Bow Creek. 8. We only allow motorized vehicles on designated roads, parking lots, campgrounds, and boat ramps (see § 27... Kirwin Reservoir by foot to bank or ice fish. 2. We only allow motorized vehicles on designated roads...

  3. Inhibition of Lipopolysaccharide-Induced Proinflammatory Responses by Buddleja officinalis Extract in BV-2 Microglial Cells via Negative Regulation of NF-kB and ERK1/2 Signaling

    Directory of Open Access Journals (Sweden)

    Hae-Ran Park

    2013-07-01

    Full Text Available Buddleja officinalis has been traditionally used in the supportive treatment of inflammatory and neuronal diseases in Korea and China. Although several reports have shown the anti-inflammatory effects of Buddleja officinalis, the anti-neuroinflammatory effect has remained unclear. In this study, we aimed to investigate the inhibitory effects of flower buds of B. officinalis Maximowicz water extract (BOWE on LPS-induced inflammatory processes in BV-2 microglial cells. BOWE dose-dependently inhibited the production of nitric oxide as well as iNOS mRNA expression. Moreover, BOWE prevented IL-1β and IL-6 mRNA expression. However, BOWE had no effect on LPS-induced COX-2 or TNF-a mRNA expression. The extract also had no effect on LPS-stimulated p38 MAPK, JNK, and c-Jun phosphorylation, whereas ERK1/2 phosphorylation was strongly inhibited by BOWE. BOWE also inhibited the LPS-induced degradation of IkB-α, and LPS-induced phosphorylation of p65 NF-kB protein. These data indicate that BOWE inhibited the nitric oxide production and pro-inflammatory gene expression in BV-2 microglial cells, possibly through a negative regulation of the NF-kB and ERK1/2 pathways. Further identification of the direct target molecule(s of BOWE is required to support its use as an anti-neuroinflammatory agent against the neurodegenerative disorders.

  4. Inhibition of lipopolysaccharide-induced proinflammatory responses by Buddleja officinalis extract in BV-2 microglial cells via negative regulation of NF-kB and ERK1/2 signaling.

    Science.gov (United States)

    Oh, Won-Jun; Jung, Uhee; Eom, Hyun-Soo; Shin, Hee-June; Park, Hae-Ran

    2013-07-31

    Buddleja officinalis has been traditionally used in the supportive treatment of inflammatory and neuronal diseases in Korea and China. Although several reports have shown the anti-inflammatory effects of Buddleja officinalis, the anti-neuroinflammatory effect has remained unclear. In this study, we aimed to investigate the inhibitory effects of flower buds of B. officinalis Maximowicz water extract (BOWE) on LPS-induced inflammatory processes in BV-2 microglial cells. BOWE dose-dependently inhibited the production of nitric oxide as well as iNOS mRNA expression. Moreover, BOWE prevented IL-1β and IL-6 mRNA expression. However, BOWE had no effect on LPS-induced COX-2 or TNF-a mRNA expression. The extract also had no effect on LPS-stimulated p38 MAPK, JNK, and c-Jun phosphorylation, whereas ERK1/2 phosphorylation was strongly inhibited by BOWE. BOWE also inhibited the LPS-induced degradation of IkB-α, and LPS-induced phosphorylation of p65 NF-kB protein. These data indicate that BOWE inhibited the nitric oxide production and pro-inflammatory gene expression in BV-2 microglial cells, possibly through a negative regulation of the NF-kB and ERK1/2 pathways. Further identification of the direct target molecule(s) of BOWE is required to support its use as an anti-neuroinflammatory agent against the neurodegenerative disorders.

  5. An explorative study on pork loin recognition

    DEFF Research Database (Denmark)

    Larsen, Anders Boesen Lindbo; Hviid, Marchen Sonja; Larsen, Rasmus

    2013-01-01

    Bag-of-words (BoW) image description has shown good performance for a large variety of image recognition scenarios. We investigate approaches to alleviating a standard BoW image description pipeline representations for the specific task of recognizing pork loins. Specifically, we extend the Bo...

  6. Dynamic analysis of iris configuration with anterior segment optical coherence tomography.

    Science.gov (United States)

    Cheung, Carol Yim-lui; Liu, Shu; Weinreb, Robert N; Liu, Jing; Li, Haitao; Leung, Dexter Yu-lung; Dorairaj, Syril; Liebmann, Jeffrey; Ritch, Robert; Lam, Dennis Shun Chiu; Leung, Christopher Kai-shun

    2010-08-01

    To evaluate dynamic changes in iris configuration and their association with anterior chamber angle width by using anterior segment optical coherence tomography (ASOCT). Forty-six normal subjects with open angles and 40 with narrow angles (Shaffer grade iris bowing were captured with real-time video recording and nasal iris bowing, nasal anterior chamber angle, and pupil diameter were measured in serial image frames selected from the video capture. The associations between iris bowing, iris thickness, anterior chamber depth (ACD), age, anterior chamber angle, and pupillary diameter measurements were evaluated with univariate and multivariate regression analyses. The relationship between iris bowing and pupil diameter was largely linear, with three dynamic patterns observed: (1) convex-to-convex (iris remains convex in dark and light); (2) concave-to-convex (iris changes from concave to convex from light to dark); and (3) concave-to-concave (iris remains concave in dark and light). All the subjects with narrow angles had convex-to-convex anatomy, although 43% of the subjects with open angles also demonstrated this pattern. These individuals were older and had shorter axial length (both with P iris bowing in the light and dark. ACD and iris bowing were independently associated with anterior chamber angle width. Independent of ACD, iris bowing is an important biometric parameter that determines angle width. Investigation of iris dynamics may offer a new perspective in understanding the risk and mechanism of primary angle closure.

  7. Content-based retrieval of focal liver lesions using bag-of-visual-words representations of single- and multiphase contrast-enhanced CT images.

    Science.gov (United States)

    Yang, Wei; Lu, Zhentai; Yu, Mei; Huang, Meiyan; Feng, Qianjin; Chen, Wufan

    2012-12-01

    This paper is aimed at developing and evaluating a content-based retrieval method for contrast-enhanced liver computed tomographic (CT) images using bag-of-visual-words (BoW) representations of single and multiple phases. The BoW histograms are extracted using the raw intensity as local patch descriptor for each enhance phase by densely sampling the image patches within the liver lesion regions. The distance metric learning algorithms are employed to obtain the semantic similarity on the Hellinger kernel feature map of the BoW histograms. The different visual vocabularies for BoW and learned distance metrics are evaluated in a contrast-enhanced CT image dataset comprised of 189 patients with three types of focal liver lesions, including 87 hepatomas, 62 cysts, and 60 hemangiomas. For each single enhance phase, the mean of average precision (mAP) of BoW representations for retrieval can reach above 90 % which is significantly higher than that of intensity histogram and Gabor filters. Furthermore, the combined BoW representations of the three enhance phases can improve mAP to 94.5 %. These preliminary results demonstrate that the BoW representation is effective and feasible for retrieval of liver lesions in contrast-enhanced CT images.

  8. Shocks in collisionless plasmas

    Science.gov (United States)

    Parks, G. K.; Lee, E.; Fu, S. Y.; Lin, N.; Liu, Y.; Yang, Z. W.

    2017-12-01

    The Earth's bow shock is the best-known collisionless shock in space. Although much is known about the bow shock, the mechanisms of heating and thermalization processes still remain poorly understood. Collisionless shocks are different from ordinary fluid shocks, because a fraction of the incident solar wind is reflected from the bow shock and the transmitted particles are not immediately thermalized. The reflected particles interact with the incident solar wind producing waves and instabilities that can heat and accelerate particles to high energies. Some of the waves can grow to large amplitudes such as Short Large Amplitude Magnetic Structures. Other upstream nonlinear structures include hot flow anomalies and density holes. The upstream nonlinear structures subsequently convect Earthward with the SW and could impact the structure and dynamics of the bow shock. These observations have clearly indicated that the upstream dynamics are an integral part of the bow shock system. Although much has been learned about the behavior of Earth's bow shock dynamics from the existing data, many fundamental questions remain not answered. This article will review observations of ion dynamics of Earth's bow shock system, what we have learned from recent and past observations. We provide new perspectives from multi-spacecraft Cluster observations about the spatial and temporal variations including the fundamental shock heating, acceleration, and entropy generation processes.

  9. SEAKEEPING PERFORMANCE OF SEMI-SWATH IN FOLLOWING SEA USING CONTROLLED FINS STABILIZER

    OpenAIRE

    Rahimuddin

    2014-01-01

    Semi-SWATH ship design is a result of combining the good features of SWATH and Catamaran designs. However, the disadvantage of semi-SWATH is that she has low restoring force at bow that causes a tendency to bow-dive when running in following seas. In some critical conditions, the foredeck was found to be immersed underwater. One of the efforts to improve the ship???s performance is to install fin stabilizers at bow and stern. The fin stabilizers are used to compensate for the low restoring fo...

  10. Digital image monitoring to optimise safe port operation

    CSIR Research Space (South Africa)

    Phelp, D

    2008-11-01

    Full Text Available -dimensioned white strips (contrast strips) were fixed onto the top and either side of the ship, to provide contrast lines for identification of the ship motions. Two mirrors placed at 45° above the bow and stern gave a vertical view of the ship’s deck... pixel width, which cut the contrast strips (one vertical line at the bow, one at the stern and one horizontal line at bow or stern). These sample lines were scanned simultaneously and were projected as a single vertical line. By stacking these lines...

  11. Complicated Congenital Dislocation of the Knee: A Case Report.

    Science.gov (United States)

    Madadi, Firooz; Tahririan, Mohammad A; Karami, Mohsen; Madadi, Firoozeh

    2016-10-01

    Congenital dislocation of the knee (CDK) is a rare disorder. We report the case of a 7-year-old girl with bilateral knee stiffness, marked anterior bowing of both legs, and inability to walk without aid. Radiologic investigation revealed bilateral knee joint dislocation accompanied by severe anterior bowing of both tibia proximally and posterior bowing of both femur distally, demonstrating a complicated congenital knee dislocation. Two-staged open reduction with proximal tibial osteotomy was performed to align the reduced knee joints. The patient was completely independent in her daily activities after surgical correction.

  12. Quantitative functional analysis of Late Glacial projectile points from northern Europe

    DEFF Research Database (Denmark)

    Dev, Satya; Riede, Felix

    2012-01-01

    that, based on metric considerations, arch-backed points (pen-knife points or Federmesser) most likely were part of a bow-and-arrow weapon system, while large tanged points (Bromme points) most likely tipped spears propelled with the help of a spear-thrower/atlatl. This paper then presents...... of the Late Glacial, followed by a disappearance of the slender backed points, later to be followed by a miniaturization of tanged points. This can be interpreted as reflecting an initial parallel use of bow and spear-thrower, followed by a loss of bow-and-arrow technology, and a subsequent reintroduction...

  13. US standards lab comes under fire

    Science.gov (United States)

    Cartlidge, Edwin

    2014-09-01

    America's National Institute of Standards and Technology is accused of bowing to the nation's spies in supporting an encryption algorithm that appears to contain a "back door", as Edwin Cartlidge reports.

  14. Psychological factors and preferences for communicating prognosis in esophageal cancer patients

    NARCIS (Netherlands)

    Franssen, Sanne J.; Lagarde, Sjoerd M.; van Werven, Jochem R.; Smets, Ellen M. A.; Tran, Khe T. C.; Plukker, John Th. M.; van Lanschot, J. Jan B.; de Haes, Hanneke C. J. M.

    2009-01-01

    Objective: Discussing prognosis is often confronting and complex for cancer patients. This study investigates bow patients' psychological characteristics relate to their preferences concerning the disclosure of prognosis. Methods: One hundred and seventy-six esophageal cancer patients participated

  15. 33 CFR 207.640 - Sacramento Deep Water Ship Channel Barge Lock and Approach Canals; use, administration, and...

    Science.gov (United States)

    2010-07-01

    ... lock. All boats, when in the lock, shall be moored to the fastenings provided for that purpose, by bow and stern lines and other spring lines as may be necessary, and the lines shall not be let go until...

  16. Underwater Vehicle

    National Research Council Canada - National Science Library

    Dick, James L

    2007-01-01

    There is thus provided an underwater vehicle having facility for maneuvering alongside a retrieving vehicle, as by manipulation of bow and stern planes, for engaging a hull surface of the retrieving...

  17. 46 CFR 122.602 - Hull markings.

    Science.gov (United States)

    2010-10-01

    ... by protrusions, the vessel must be fitted with a reliable draft indicating system from which the bow and stern drafts can be determined. (g) On a vessel on which the number of passengers permitted on...

  18. 75 FR 41483 - Environmental Impacts Statements; Notice of Availability

    Science.gov (United States)

    2010-07-16

    ..., Hahns Peak/Bear Ears Ranger District, Medicine Bow-Routt National Forests, Routt County, CO, Wait Period... Implementation, San Mateo and Santa Clara Counties, CA, Comment Period Ends: 08/30/2010, Contact: Gary Stern, 707...

  19. Active faulting on the Ninetyeast Ridge and its relation to deformation of the Indo-Australian plate

    Digital Repository Service at National Institute of Oceanography (India)

    Sager, W.W.; Bull, J.M.; Krishna, K.S.

    of volcanic ash cored at DSDP Site 253 [Shipboard Scientific Party, 1974]. Faults were recognized by vertical offsets or discontinuities of sedimentary layers, monoclinal folds, bowing or kinking of sedimentary layers, coherent diffractions cutting...

  20. The National Shipbuilding Research Program. 1993 Ship Production Symposium. Paper No. 14: Composites for Large Ships

    National Research Council Canada - National Science Library

    Horsmon, Jr, Albert W

    1993-01-01

    .... Potential uses on large cargo vessels include bulbous bows, hatch covers, stern fairings, deck machinery enclosures and non-structural interiors. This paper reviews current usage and explores future potential on the use of composites on larger vessels.

  1. Navy Ship Propulsion Technologies: Options for Reducing Oil Use - Background for Congress

    National Research Council Canada - National Science Library

    O'Rourke, Ronald

    2006-01-01

    ...%. The Navy has installed fuel-saving bulbous bows and stern flaps on many of its ships. Ship fuel use could be reduced by shifting to advanced turbine designs such as an intercooled recuperated (ICR) turbine...

  2. 46 CFR 169.521 - Stowage.

    Science.gov (United States)

    2010-10-01

    ... of davits. (2) Lifeboats must not be stowed in the bow of the vessel nor so far aft as to be endangered by the propellers or overhang of the stern. (3) Lifeboats must be stowed so that it is not...

  3. 46 CFR 97.40-10 - Draft marks and draft indicating systems.

    Science.gov (United States)

    2010-10-01

    ... reliable draft indicating system from which the bow and stern drafts can be determined. ... rudderpost or at any place at the stern of the vessel as may be necessary for easy observation. The bottom of...

  4. 46 CFR 196.40-10 - Draft marks and draft indicating systems.

    Science.gov (United States)

    2010-10-01

    ... reliable draft indicating system from which the bow and stern drafts can be determined. ... rudderpost or at any place at the stern of the vessel as may be necessary for easy observance. The bottom of...

  5. Modelling of tidal hydrodynamics for a tropical ecosystem with implications for pollutant dispersion (Cochin Estuary, Southwest India)

    Digital Repository Service at National Institute of Oceanography (India)

    Balachandran, K.K.; Reddy, G.S.; Revichandran, C.; Srinivas, K.; Vijayan, P.R.; Thottam, T.J.

    of residual currents and particle trajectories are discussed. 2. Background The Cochin Estuary constitutes a complex estuarine system (Fig.1), characterized by an ox-bow shape with its long axes running parallel to the coast and numerous islands (Soman...

  6. 46 CFR 154.1872 - Cargo emergency jettisoning.

    Science.gov (United States)

    2010-10-01

    ... jettisoning. (a) The master shall ensure that emergency jettisoning piping under § 154.356, except bow and stern loading and discharging piping, is only used when an emergency exists. (b) Emergency jettisoning...

  7. 46 CFR 32.05-1 - Draft marks and draft indicating systems-TB/ALL.

    Science.gov (United States)

    2010-10-01

    ... reliable draft indicating system from which the bow and stern drafts can be determined. ... rudderpost or at any place at the stern of the vessel as may be necessary for easy observance. The bottom of...

  8. Basement configuration of KG offshore basin from magnetic anomalies

    Digital Repository Service at National Institute of Oceanography (India)

    Subrahmanyam, V.; Swamy, K.V.; Raj, N.

    to Dept. of Science & Technology, New Delhi for granting the Junior Research Fel- lowship through Inspire Programme. This is NIO (CSIR) contribution no. 7132. References Aftalion M, Bowes D R, Dash B and Dempster T J 1988 Late proterozoic charnockites...

  9. Global patterns and predictions of seafloor biomass using random forests

    Digital Repository Service at National Institute of Oceanography (India)

    Wei, Chih-Lin; Rowe, G.T.; Escobar-Briones, E.; Boetius, A.; Soltwedel, T.; Caley, M.J.; Soliman, Y.; Huettmann, F.; Qu, F.; Yu, Z.; Pitcher, C.R.; Haedrich, R.L.; Wicksten, M.K.; Rex, M.A.; Baguley, J.G.; Sharma, J.; Danovaro, R.; MacDonald, I.R.; Nunnally, C.C.; Deming, J.W.; Montagna, P.; Levesque, M.; Weslawsk, J.M.; Wlodarska-Kowalczuk, M.; Ingole, B.S.; Bett, B.J.; Billett, D.S.M.; Yool, A.; Bluhm, B.A.; Iken, K.; Narayanaswamy, B.E.

    forms (meiofauna, microfauna, bacteria and viruses), sampling problems are solved seemingly easily by utilizing small- diameter cores, but care has to be taken not to lose organisms by either washing or bow-wake of sampling devices. For these groups...

  10. Vertical Photographs

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set includes of photographs of marine mammals and sea turtles taken with high resolution cameras mounted in airplanes, unmanned platforms or the bow of...

  11. Genetics Home Reference: hypophosphatasia

    Science.gov (United States)

    ... abnormalities similar to another childhood bone disorder called rickets . Affected infants are born with short limbs, an ... of the first signs of the condition in children. Affected children may have short stature with bowed ...

  12. Travelers' Health: International Adoption

    Science.gov (United States)

    ... findings of sexual abuse Extremities: presence of bowing (rickets) or deformities Neurologic: presence and quality of reflexes In addition, all children should receive a developmental screening by a clinician ...

  13. Disease: H00761 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available dysplasia (SEMD) characterized by short, bowed lower limbs, mild brachydactyly, enlarged knee joints, and e...arly-onset osteoarthropathy. Radiographs show delayed epiphyseal ossification in hips and knees. Nonsense mu

  14. VLF Cutler: September 1997 Four-Panel Tests; RADHAZ and Field Strength Measurement

    National Research Council Canada - National Science Library

    Hansen, P

    1998-01-01

    The objective of the four panel tests was to provide VLF Cutler with the capability of performing the special painting project and normal maintenance on the bow tie area towers of an inactive array...

  15. MEDLINE Abstracts Classification Based on Noun Phrases Extraction

    Science.gov (United States)

    Ruiz-Rico, Fernando; Vicedo, José-Luis; Rubio-Sánchez, María-Consuelo

    Many algorithms have come up in the last years to tackle automated text categorization. They have been exhaustively studied, leading to several variants and combinations not only in the particular procedures but also in the treatment of the input data. A widely used approach is representing documents as Bag-Of-Words (BOW) and weighting tokens with the TFIDF schema. Many researchers have thrown into precision and recall improvements and classification time reduction enriching BOW with stemming, n-grams, feature selection, noun phrases, metadata, weight normalization, etc. We contribute to this field with a novel combination of these techniques. For evaluation purposes, we provide comparisons to previous works with SVM against the simple BOW. The well known OHSUMED corpus is exploited and different sets of categories are selected, as previously done in the literature. The conclusion is that the proposed method can be successfully applied to existing binary classifiers such as SVM outperforming the mixture of BOW and TFIDF approaches.

  16. 75 FR 51107 - Notice of Proposed Supplementary Rules for Public Lands in Routt County, CO: Emerald Mountain...

    Science.gov (United States)

    2010-08-18

    ... firearms, air rifles, pellet and BB guns, spring guns, bows and arrows, slings, paint ball markers, other..., fire, emergency, or law enforcement vehicle being used for emergency purposes; and Any vehicle whose...

  17. Japanese-American Communication: Mysteries, Enigmas, and Possibilities.

    Science.gov (United States)

    Bowman, Joel P.; Okuda, Tsugihiro

    1985-01-01

    Examines some of the differences between Americans and Japanese and shows how these differences influence perception and communication. Focuses on the bow and handshake, politeness, thoughtfulness, formality, social relationships, specificity and exaggeration, language, holidays, and possibilities for communication. (EL)

  18. Disease: H00761 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available l dysplasia (SEMD) characterized by short, bowed lower limbs, mild brachydactyly, enlarged knee joints, and ...early-onset osteoarthropathy. Radiographs show delayed epiphyseal ossification in hips and knees. Nonsense m

  19. Islamic Radicalism in North Africa Force Works, For Now

    National Research Council Canada - National Science Library

    Lewis, William

    1996-01-01

    .... Islamists in Algeria lost the presidential election held in November 1995, and the Muslim Brotherhood in Egypt bowed to government tactics of arrests and a ban on political activity in elections held last fall...

  20. 77 FR 23497 - Notice of Intent To Repatriate Cultural Items: Benton County Historical Society and Museum...

    Science.gov (United States)

    2012-04-19

    ... shells and small round black glass beads; 1 ceremonial bow; and 1 associated arrow. All of the items are... collected by Doctor Hill during a period of sixty years from all parts of the earth regardless of expense...

  1. 46 CFR 111.10-1 - Definitions.

    Science.gov (United States)

    2010-10-01

    .... (b) Drilling loads means all loads associated exclusively with the drilling operation including power to the drill table, mud system, and positioning equipment. ... motor, bow thruster motor, cargo transfer, drilling, cargo refrigeration for other than Class 5.2...

  2. Analysis and design of offshore tubular members against ship impacts

    OpenAIRE

    Yu, Zhaolong; Amdahl, Jørgen

    2018-01-01

    Ship collisions may be critical to the operational safety of ships and offshore structures, and should be carefully designed against. This paper investigates the response of offshore tubular members subjected to vessel bow and stern impacts with the nonlinear finite element code LS-DYNA. Two 7500 tons displacement supply vessels of modern design are modeled. Force-displacement curves for bow and stern indentation by rigid tubes are compared with design curves in the DNV-GL RP C204. Next, both...

  3. 76 FR 45518 - Takes of Marine Mammals Incidental to Specified Activities; Low-Energy Marine Geophysical Survey...

    Science.gov (United States)

    2011-07-29

    ...), and a full load draft of 5.8 m (19 ft). It is equipped with twin 360 azimuth stern thrusters each powered by a 3,000 horsepower (hp) DC motor and a water-jet bow thruster powered by a 1,600 hp DC motor..., 2010). Some dolphins seem to be attracted to the seismic vessel and floats, and some ride the bow wave...

  4. WEISMANN-NETTER-STUHL SYNDROME: A RARE FORM OF SKELETAL DYSPLASIA

    Directory of Open Access Journals (Sweden)

    Dr. Shalini Tripathi

    2009-07-01

    Full Text Available A case of Weismann-Netter-Stuhl syndrome was described because of its rare entity in pediatric age group. The clinical presentation was short stature with bowing of lower legs with characteristic radiological findings. It was differentiated from congenital syphilis and rickets by negative laboratory results and the characteristic radiographic features of anterior and medial bowing of the mid to distal third of the tibiae and fibulae and cortical hyperostosis of the concave margins.

  5. BLC Bank - Lebanon : Leading in Banking on Women

    OpenAIRE

    International Finance Corporation

    2016-01-01

    The overall objective of this study is to learn about the impact of International Finance Corporation’s (IFC) Banking on Women (BoW) Program in the Europe and Central Asia and the Middle East and North Africa (EMENA) through BLC Bank of Lebanon. The objective of this specific case study is to understand the success of the BoW program for BLC Bank in Lebanon in terms of the program’s contri...

  6. Updated Vertical Extent of Collision Damage

    DEFF Research Database (Denmark)

    Tagg, R.; Bartzis, P.; Papanikolaou, P.

    2002-01-01

    The probabilistic distribution of the vertical extent of collision damage is an important and somewhat controversial component of the proposed IMO harmonized damage stability regulations for cargo and passenger ships. The only pre-existing vertical distribution, currently used in the international...... cargo ship regulations, was based on a very simplified presumption of bow heights. This paper investigates the development of this damage extent distribution based on three independent methodologies; actual casualty measurements, world fleet bow height statistics, and collision simulation modeling...

  7. The Cognitive, Perceptual, and Neural Bases of Skilled Performance

    Science.gov (United States)

    1994-02-01

    memory (STMi) in a way that mimics cognitive data about working memory, including primacy , recency , and bowed order and error gradients. As new items are...also shown how network parameters control the type and shape of primacy , recency , or bowed temporal order gradients that will be stored. t Supported...Transient Tritanopia/Euchrornatopsia 58 4. Electrophysiology: Color 58 5. Electroplysiology: Spatial Effects : ERG 59 6. Electrophysiology: Spatial

  8. Disease: H00846 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available H00846 Fuhrmann syndrome; Fibular aplasia or hypoplasia, femoral bowing and poly-, ...syn-, and oligodactyly Fuhrmann syndrome is a non-lethal limb malformation disorder with various degrees of limb aplasia/hypoplasia... and joint dysplasia. Major manifestations include hypoplasia of the pelvis, aplasia or hypoplasia... of fibulae, severe bowing of femora, absence of nails, and polydactyly. Skeletal dysplasia...ption) Fuhrmann W, Fuhrmann-Rieger A, de Sousa F Poly-, syn- and oligodactylyl, aplasia or hypoplasia of fibula, hypoplasia

  9. Occurrence and endocrine effects of agrichemicals in a small Nebraska, USA, watershed.

    Science.gov (United States)

    Sellin Jeffries, Marlo K; Abbott, Kelty I; Cowman, Tim; Kolok, Alan S

    2011-10-01

    The Bow Creek watershed (Nebraska, USA) is dominated by the production of beef cattle and row crops; therefore, surface waters are likely to receive runoff containing steroid hormones and pesticides. The goal of the present study was to determine the occurrence and endocrine effects of agrichemicals in this watershed. To accomplish this, four sites within the watershed-Pearl, Bow, and East Bow Creeks and a site at the confluence with the Missouri River-were selected. In June of 2008, polar organic chemical integrative samplers (POCIS) were deployed at each site, whereas in June of 2009, water and sediment samples were collected. Caged fathead minnows (Pimephales promelas) were deployed at all of the selected sites in both years. Analysis of these samples revealed that steroid hormones were not present; however, pesticides were present in POCIS extracts and water samples. In general, the amount of pesticides was higher in POCIS retrieved from Pearl and Bow Creeks than in POCIS from East Bow Creek and the confluence. This variation between sites appeared to be related to row crop density, as row crop land cover surrounding the Pearl and Bow Creek sites was higher than that surrounding the East Bow and confluence sites. To determine the endocrine effects of agrichemicals within this watershed, the hepatic mRNA expression of vitellogenin and estrogen receptor α (ERα), as well as the gonadal expression of P450 aromatase A, was determined for the caged minnows. Females deployed at East Bow Creek and the confluence experienced decreases in the expression of ERα, suggesting that these females had been defeminized; however, this defeminization could not be attributed to any of the pesticides detected at these sites. Copyright © 2011 SETAC.

  10. Characteristics of Task-specific Tremor in String Instrument Players

    Directory of Open Access Journals (Sweden)

    André Lee

    2014-06-01

    Full Text Available Background: In recent studies primary bowing tremor has been described; however, tremor frequency has never been quantitatively assessed. In addition to describing phenomenological aspects of tremor we thus aimed at assessing tremor frequency. Our hypothesis was that primary bowing tremor is similar to the phenomenological aspects and frequency of primary writing tremor.Methods: We quantified primary bowing tremor in four violinists under two conditions: open strings and a G major scale. Data were analyzed using empirical mode decomposition because it takes into account non‐stationarity and non‐linearity of signals. For each patient we further described tremor phenomenology and assessed symptom onset, risk factors, medication, and family history with a structured anamnesis. We compare the findings to previous findings for primary bowing tremor and primary writing tremor.Results: We mainly found a flexion–extension tremor of the wrist with a frequency range of 4.7–6.7 Hz. There was no significant difference between the conditions. Mean onset age was 43±2.4 years. Medication included trihexyphenidyl, propranolol, primidone, and botulinum toxin. We found a positive family history in two patients and an injury prior to symptom onset in another two patients. Comparison of onset age, frequency range, family history, and injuries prior to onset revealed that our findings are very similar to previous findings on primary bowing tremor and primary writing tremor.Discussion: Our findings confirmed our hypothesis that primary bowing tremor is similar to primary writing tremor, with regard to phenomenology and epidemiology as well as tremor frequency. There was no difference in tremor frequency between conditions, suggesting that tremor is not influenced by bimanual coordination or bowing speed. Our findings thus provide new phenomenological aspects and may contribute to a better understanding of primary bowing tremor.

  11. Review of Hull Structural Monitoring Systems for Navy Ships

    Science.gov (United States)

    2013-05-01

    cases of uniaxial strain, the dummy gauge is attached perpendicularly to the active gauge. The dummy gauge is connected in a Wheatstone bridge ...interface (GUI) on the bridge . A more typical configuration with four long-base strain gauges (LBSGs) is however illustrated in Figure 2. In this...in the bow to measure slamming incidents, bow emergence and slamming pressures. On larger vessels where the deckhouse and bridge are located aft

  12. The Role of Hydromagnetic Waves in the Magnetosphere and the Ionosphere

    Science.gov (United States)

    1988-05-01

    diffuse aurora , Geophys. Res. Lett.. 6, 332, 1979. J. D. Winningham, and B. W. Reinisch, F layer ionization patches Ossakow, S. L., K. Papadopoulos J...Davis, 1971], in the high speed streams of the solar wind [Abraham-Shrauner and Feldman, 1977], in the upstream of the Jovian bow shock (Goldstein, et al...hand polarized finite amplitude Alien waves have also been observed in the upstream of the Jovian bow shock [Goldstein, et al., 1985]. It is shown

  13. Uranium assessment for the Precambrian pebble conglomerates in southeastern Wyoming

    Energy Technology Data Exchange (ETDEWEB)

    Borgman, L.E.; Sever, C.; Quimby, W.F.; Andrew, M.E.; Karlstrom, K.E.; Houston, R.S.

    1981-03-01

    This volume is a geostatistical resource estimate of uranium and thorium in quartz-pebble conglomerates, and is a companion to Volume 1: The Geology and Uranium Potential to Precambrian Conglomerates in the Medicine Bow Mountains and Sierra Madre of Southeastern Wyoming; and to Volume 2: Drill-Hole Data, Drill-Site Geology, and Geochemical Data from the Study of Precambrian Uraniferous Conglomerates of the Medicine Bow Mountains and the Sierra Madre of Southeastern Wyoming.

  14. Isolated femoral hypoplasia: an intrauterine differential diagnosis to campomelia

    Energy Technology Data Exchange (ETDEWEB)

    Koerber, Friederike; Benz-Bohm, Gabriele [University of Cologne, Department of Paediatric Radiology, Cologne (Germany); Schoenau, Eckard [University of Cologne, Department of Paediatrics, Cologne (Germany); Horwitz, A.Eldad [Klinikum Krefeld, Department of Paediatric Radiology, Krefeld (Germany)

    2005-06-01

    The isolated form of femoral bowing is an important differential diagnosis of campomelia. Therefore, knowledge of isolated anomalies is fundamental for prenatal diagnosis, especially for the differential diagnosis from severe syndromes. Four cases are presented to discuss the differential diagnosis of femoral bowing including a review of the literature. We report four newborn babies with unilateral bowing and shortening of the femur. Three had no further anomaly; one child had additional abnormalities due to coumarin embryopathy. The radiological findings were shortened femora with bowing and varus deformity and cortical thickening on the concave side. All other parts showed normal bone structure. The aetiology of femoral bowing is unknown. Early damage of the cartilaginous model followed by remodelling with thickening on the concave side of the bone similar to the healing of malaligned fractures is suspected. The isolated form of femoral bowing without any other anomalies has to be differentiated from complex and more often severe congenital syndromes such as campomelia. Postpartum radiological examination should be reduced to a single exposure of the affected limb and follow-up should be done by clinical examination. (orig.)

  15. Foreshock and magnetosheath transients, origin and connection to the magnetopause.

    Science.gov (United States)

    Blanco-Cano, X.

    2014-12-01

    The solar wind interaction with earths's magnetosphere begins well ahead of the magnetopause when the solar wind encounters the foreshock, bow shock and magnetosheath. In these regions a variety of waves and magnetic structures exist and modify the solar wind. The foreshock is permeated by a variety of ultra low frequency (ULF) waves and magnetic transient structures such as shocklets, SLAMs, and cavitons. These structures are very compressive and are generated by the solar wind interaction with backstreaming particles plus non linear processes. Other structures such as hot flow anomalies (HFA), and spontaneous hot flow anomalies (SHFA) can also exist in the foreshock. HFAs are generated by discontinuities that arrive to the bow shock. Recent studies show that SHFA have the same profiles as HFA, but form by the interaction of foreshock cavitons with the bowshock. Foreshock bubbles can form when energetic ions upstream of the quasi-parallel bow shock interact with rotational discontinuities in the solar wind. All these structures can merge with the bow shock and be convected into the magnetosheath. The magnetosheath is both a place for rich plasma physical processes and a filter between solar wind and the magnetospheric plasma and magnetic field environments. It is permeated by the superposition of upstream convected structures plus locally generated waves (ion cyclotron and mirror mode). Recent studies have shown that jets and magnetosheath filamentary structures (MFS) can be observed downstream from the bow shock. Jets are associated to shock rippling efects and MFS to acceleration of particles at and near the shock. Due to the presence of the foreshock, bow shock and magnetosheath transients, the solar wind arriving to the magnetopause is very different to the pristine solar wind. In this talk we will address the main characteristics of these transients, discuss their origin, and how they can modify the solar wind, the bow shock, the magnetosheath and the

  16. Visual dictionaries as intermediate features in the human brain

    Directory of Open Access Journals (Sweden)

    Kandan eRamakrishnan

    2015-01-01

    Full Text Available The human visual system is assumed to transform low level visual features to object and scene representations via features of intermediate complexity. How the brain computationally represents intermediate features is still unclear. To further elucidate this, we compared the biologically plausible HMAX model and Bag of Words (BoW model from computer vision. Both these computational models use visual dictionaries, candidate features of intermediate complexity, to represent visual scenes, and the models have been proven effective in automatic object and scene recognition. These models however differ in the computation of visual dictionaries and pooling techniques. We investigated where in the brain and to what extent human fMRI responses to short video can be accounted for by multiple hierarchical levels of the HMAX and BoW models. Brain activity of 20 subjects obtained while viewing a short video clip was analyzed voxel-wise using a distance-based variation partitioning method. Results revealed that both HMAX and BoW explain a significant amount of brain activity in early visual regions V1, V2 and V3. However BoW exhibits more consistency across subjects in accounting for brain activity compared to HMAX. Furthermore, visual dictionary representations by HMAX and BoW explain significantly some brain activity in higher areas which are believed to process intermediate features. Overall our results indicate that, although both HMAX and BoW account for activity in the human visual system, the BoW seems to more faithfully represent neural responses in low and intermediate level visual areas of the brain.

  17. Stochastic aspects of motor behavior and their dependence on auditory feedback in experienced cellists.

    Science.gov (United States)

    Chen, Jessie; Woollacott, Marjorie; Pologe, Steve; Moore, George P

    2013-01-01

    This study aimed to investigate movement accuracy of experienced cellists, the statistical properties of their note sequences during a reciprocal task, and the degree to which these movement characteristics depend on auditory feedback. Nine experienced cellists were asked to shift alternately between two notes using only their index finger to make contact with the string and fingerboard. Shifting sequences continued for two minutes at a rate of one note per second. The task was performed under two conditions: with auditory feedback (provided by the bow) or without auditory feedback (i.e., without the use of bow). When the bow was used, subjects had no difficulty in shifting between target notes with precision and stability. Some variability was present, but notes in these sequences were generally uncorrelated. The contact data and correlations in most bowed trials resembled those expected of a renewal process, a process in which successive values are statistically independent and identically distributed. Without the bow, subjects lost their ability to reach the same target positions accurately; contact locations tended to drift and had a random quality, indicating that without the bow subjects were uncertain of the target location in relation to the spatial location of their fingertips. Within these unbowed sequences, finger positions were highly correlated-within and between note sequences. In some trials without the bow, the statistical correlation patterns of the sequence were consistent with the expectations of a discrete Wiener process. Throughout our study, computer simulations of renewal and Wiener processes enabled us to determine the types of correlations to be expected from these theoretical models. The implications of the statistical results in terms of subject behavior are discussed.

  18. Stochastic aspects of motor behavior and their dependence on auditory feedback in experienced cellists

    Directory of Open Access Journals (Sweden)

    Jessie eChen

    2013-07-01

    Full Text Available This study aimed to investigate movement accuracy of experienced cellists, the statistical properties of their note sequences during a reciprocal task, and the degree to which these movement characteristics depend on auditory feedback. Nine experienced cellists were asked to shift alternately between two notes using only their index finger to make contact with the string and fingerboard. Shifting sequences continued for two minutes at a rate of one note per second. The task was performed under two conditions: with auditory feedback (provided by the bow or without auditory feedback (i.e., without the use of bow. When the bow was used, subjects had no difficulty in shifting between target notes with precision and stability. Some variability was present, but notes in these sequences were generally uncorrelated. The contact data and correlations in most bowed trials resembled those expected of a renewal process, a process in which successive values are statistically independent and identically distributed. Without the bow, subjects lost their ability to reach the same target positions accurately; contact locations tended to drift and had a random quality, indicating that without the bow subjects were uncertain of the target location in relation to the spatial location of their fingertips. Within these unbowed sequences, finger positions were highly correlated-- within and between note sequences. In some trials without the bow, the statistical correlation patterns of the sequence were consistent with the expectations of a discrete Wiener process. Throughout our study, computer simulations of renewal and Wiener processes enabled us to determine the types of correlations to be expected from these theoretical models. The implications of the statistical results in terms of subject behavior are discussed.

  19. Tracheal CT morphology: correlation with distribution and extent of thoracic adipose tissue

    Energy Technology Data Exchange (ETDEWEB)

    Ap Dafydd, Derfel [Imperial College Healthcare NHS Trust, Department of Radiology, Charing Cross Hospital, London (United Kingdom); Desai, Sujal R. [King' s College Hospital NHS Foundation Trust, King' s College London, King' s Health Partners, London (United Kingdom); Gordon, Fabiana; Copley, Susan J. [Imperial College, London (United Kingdom)

    2016-10-15

    To evaluate the relationship between adipose tissue measurements and anterior bowing of the posterior tracheal wall in a large nonselected group of patients undergoing CT pulmonary angiography (CTPA). Consecutive patients undergoing CTPA over a 4-month period were analyzed retrospectively. Using an adapted scoring system (posterior bowing, flattening, mild/moderate or severe anterior bowing of the posterior tracheal membrane), the axial morphology and cross-sectional area of the trachea at the narrowest point and 1 cm above the aortic arch were evaluated. Measurements of adipose tissue were taken (anterior mediastinal fat width, sagittal upper abdominal diameter and subcutaneous fat thickness at the level of the costophrenic angle). Relationships between tracheal morphology and measurements of adipose tissue were analyzed. 296 patients were included (120 males, 176 females, mean age 59 years, range 19-90). Severe anterior bowing of the posterior tracheal wall correlated with increasing sagittal upper abdominal diameter (p = 0.002). Mild/moderate and severe anterior bowing of the posterior tracheal wall correlated with increasing mediastinal fat width (p = 0.000 and p = 0.031, respectively). Tracheal cross-sectional area was inversely correlated with increasing subcutaneous fat thickness (p = 0.022). The findings demonstrate a statistically significant relationship between CT tracheal morphology and adipose tissue measurements in a large nonselected population. (orig.)

  20. Spatial distribution of upstream magnetospheric ≥50 keV ions

    Directory of Open Access Journals (Sweden)

    G. C. Anagnostopoulos

    2000-01-01

    Full Text Available We present for the first time a statistical study of \\geq50 keV ion events of a magnetospheric origin upstream from Earth's bow shock. The statistical analysis of the 50-220 keV ion events observed by the IMP-8 spacecraft shows: (1 a dawn-dusk asymmetry in ion distributions, with most events and lower intensities upstream from the quasi-parallel pre-dawn side (4 LT-6 LT of the bow shock, (2 highest ion fluxes upstream from the nose/dusk side of the bow shock under an almost radial interplanetary magnetic field (IMF configuration, and (3 a positive correlation of the ion intensities with the solar wind speed and the index of geomagnetic index Kp, with an average solar wind speed as high as 620 km s-1 and values of the index Kp > 2. The statistical results are consistent with (1 preferential leakage of ~50 keV magnetospheric ions from the dusk magnetopause, (2 nearly scatter free motion of ~50 keV ions within the magnetosheath, and (3 final escape of magnetospheric ions from the quasi-parallel dawn side of the bow shock. An additional statistical analysis of higher energy (290-500 keV upstream ion events also shows a dawn-dusk asymmetry in the occurrence frequency of these events, with the occurrence frequency ranging between ~16%-~34% in the upstream region.Key words. Interplanetary physics (energetic particles; planetary bow shocks

  1. A robust design mark-resight abundance estimator allowing heterogeneity in resighting probabilities

    Science.gov (United States)

    McClintock, B.T.; White, Gary C.; Burnham, K.P.

    2006-01-01

    This article introduces the beta-binomial estimator (BBE), a closed-population abundance mark-resight model combining the favorable qualities of maximum likelihood theory and the allowance of individual heterogeneity in sighting probability (p). The model may be parameterized for a robust sampling design consisting of multiple primary sampling occasions where closure need not be met between primary occasions. We applied the model to brown bear data from three study areas in Alaska and compared its performance to the joint hypergeometric estimator (JHE) and Bowden's estimator (BOWE). BBE estimates suggest heterogeneity levels were non-negligible and discourage the use of JHE for these data. Compared to JHE and BOWE, confidence intervals were considerably shorter for the AICc model-averaged BBE. To evaluate the properties of BBE relative to JHE and BOWE when sample sizes are small, simulations were performed with data from three primary occasions generated under both individual heterogeneity and temporal variation in p. All models remained consistent regardless of levels of variation in p. In terms of precision, the AICc model-averaged BBE showed advantages over JHE and BOWE when heterogeneity was present and mean sighting probabilities were similar between primary occasions. Based on the conditions examined, BBE is a reliable alternative to JHE or BOWE and provides a framework for further advances in mark-resight abundance estimation. ?? 2006 American Statistical Association and the International Biometric Society.

  2. Spatial distribution of upstream magnetospheric ≥50 keV ions

    Directory of Open Access Journals (Sweden)

    G. Kaliabetsos

    Full Text Available We present for the first time a statistical study of geq50 keV ion events of a magnetospheric origin upstream from Earth's bow shock. The statistical analysis of the 50-220 keV ion events observed by the IMP-8 spacecraft shows: (1 a dawn-dusk asymmetry in ion distributions, with most events and lower intensities upstream from the quasi-parallel pre-dawn side (4 LT-6 LT of the bow shock, (2 highest ion fluxes upstream from the nose/dusk side of the bow shock under an almost radial interplanetary magnetic field (IMF configuration, and (3 a positive correlation of the ion intensities with the solar wind speed and the index of geomagnetic index Kp, with an average solar wind speed as high as 620 km s-1 and values of the index Kp > 2. The statistical results are consistent with (1 preferential leakage of ~50 keV magnetospheric ions from the dusk magnetopause, (2 nearly scatter free motion of ~50 keV ions within the magnetosheath, and (3 final escape of magnetospheric ions from the quasi-parallel dawn side of the bow shock. An additional statistical analysis of higher energy (290-500 keV upstream ion events also shows a dawn-dusk asymmetry in the occurrence frequency of these events, with the occurrence frequency ranging between ~16%-~34% in the upstream region.Key words. Interplanetary physics (energetic particles; planetary bow shocks

  3. Rapid Prediction of Damage to Struck and Striking Vessels in a Collision Event

    DEFF Research Database (Denmark)

    Lützen, Marie; Simonsen, Bo Cerup; Pedersen, Preben Terndrup

    2000-01-01

    This paper presents theory and application examples of a mathematical model for rapid prediciton of damage to both the side structure of a struck vessel and the bow of a striking vessel in a collision event.The geometry of the bow of the striking ship is idealised such that it can be described...... by only few parameters, still covering with sufficient accuracy almost all existing ship bows with and without bulbs.The model for the internal mechanics of the struck ship side is based on a set of so-called superelements. Each super-element represents an assembly of structural components and contains...... solutions for the structural behaviour of this assembly under deep collapse. By suming up the crushing force of each super-element, it is possible to determine the total contact load between the two involved ships.A number of parameter studies are presented where the sensitivity of the damage to the loading...

  4. Analysis of Ship Groundings on Soft Sea Beds

    DEFF Research Database (Denmark)

    Simonsen, Bo Cerup; Pedersen, Preben Terndrup

    1997-01-01

    The consequences associated with ships running aground depend very much on the soil characteristics of the sea bed and the geometrical shape of the ship bow. The penetration into the sea bed depends on these factors and the penetration is an important factor for the ship motion because...... it influences the ship heave and pitch motions as well as the friction between the ship and the soil.In this paper a rational calculation model is presented for the sea bed soil reaction forces on the ship bottom. The model is based on the assumption that the penetration of the ship bow generates a flow of pore...... by the theory of frictional soils in rupture. Frictional stresses on the bow surface are assumed to be related to the normal pressure by a simple Coulumb relation. The total soil reaction as a function of velocity and penetration is found by integration of normal pressure and frictional stresses over...

  5. Full Scale Measurements of the Hydro-Elastic Response of Large Container Ships for Decision Support

    DEFF Research Database (Denmark)

    Andersen, Ingrid Marie Vincent

    and slender bow and stern sections) and their normal cargo loading condition, container ships are typically operated in a still-water hogging condition (tension in deck and compression in the bottom structure). The wave-induced bending moment is added to the still-water bending moment, which, together...... frequency with the waves. Together with the relatively high design speed and often pronounced bow flare this makes large container ship more sensitive to slamming and, consequently, the effects of wave-induced hull girder vibrations. From full scale strain measurements of individual, measured hull girder......, but, in addition to ship size, speed and bow flare angle are also believed to be important factors contributing to the hull girder vibrations. The hull girder vibrational response is found to be dominated by the 2-node vertical bending mode. No torsional vibrations are found but torsion may, however...

  6. Singlet exciton condensation and bond-order-wave phase in the extended Hubbard model

    Science.gov (United States)

    Hafez-Torbati, Mohsen; Uhrig, Götz S.

    2017-09-01

    The competition of interactions implies the compensation of standard mechanisms, which leads to the emergence of exotic phases between conventional phases. The extended Hubbard model (EHM) is a fundamental example for the competition of the local Hubbard interaction and the nearest-neighbor density-density interaction, which at half-filling and in one dimension leads to a bond-order wave (BOW) between a charge-density wave (CDW) and a quasi-long-range order Mott insulator. We study the full momentum-resolved excitation spectrum of the one-dimensional EHM in the CDW phase, and we clarify the relation between different elementary energy gaps. We show that the CDW-to-BOW transition is driven by the softening of a singlet exciton at momentum π . The BOW is realized as the condensate of this singlet exciton.

  7. Overlap between Fibular Aplasia, Tibial Campomelia, and Oligosyndactyly and Fuhrmann's Syndromes in an Egyptian Female Infant.

    Science.gov (United States)

    Abdalla, Ebtesam M; El-Beheiry, Ahmed A

    2017-06-01

    We report a rare congenital limb defect with combined features of both fibular aplasia, tibial campomelia, and oligosyndactyly (FATCO) and Fuhrmann's syndromes. A female newborn infant, born to nonconsanguineous Egyptian parents, presented with isolated abnormalities of the lower limbs comprising bilateral shortening and anterior bowing of the lower limbs at the distal third of the tibia and split foot. Radiographic examination revealed complete absence of both fibulae, anterolateral bowing and shortening of the tibia, bowing of the femora, and absence of several metatarsal and phalangeal bones. The upper limbs were clinically and radiologically normal, and the infant had neither facial dysmorphism nor other associated visceral anomalies. The presented case highlights an extremely rare limb deficiency syndrome, and together with additional case reports, it could be useful to further delineate this condition.

  8. Multi-wavelength mid-infrared plasmonic antennas with single nanoscale focal point.

    Science.gov (United States)

    Blanchard, Romain; Boriskina, Svetlana V; Genevet, Patrice; Kats, Mikhail A; Tetienne, Jean-Philippe; Yu, Nanfang; Scully, Marlan O; Dal Negro, Luca; Capasso, Federico

    2011-10-24

    We propose and demonstrate a novel photonic-plasmonic antenna capable of confining electromagnetic radiation at several mid-infrared wavelengths to a single sub-wavelength spot. The structure relies on the coupling between the localized surface plasmon resonance of a bow-tie nanoantenna with the photonic modes of surrounding multi-periodic particle arrays. Far-field measurements of the transmission through the central bow-tie demonstrate the presence of Fano-like interference effects resulting from the interaction of the bow-tie antenna with the surrounding nanoparticle arrays. The near-field of the multi-wavelength antenna is imaged using an aperture-less near-field scanning optical microscope. This antenna is relevant for the development of near-field probes for nanoimaging, spectroscopy and biosensing. © 2011 Optical Society of America

  9. Automated classification of histopathology images of prostate cancer using a Bag-of-Words approach

    Science.gov (United States)

    Sanghavi, Foram M.; Agaian, Sos S.

    2016-05-01

    The goals of this paper are (1) test the Computer Aided Classification of the prostate cancer histopathology images based on the Bag-of-Words (BoW) approach (2) evaluate the performance of the classification grade 3 and 4 of the proposed method using the results of the approach proposed by the authors Khurd et al. in [9] and (3) classify the different grades of cancer namely, grade 0, 3, 4, and 5 using the proposed approach. The system performance is assessed using 132 prostate cancer histopathology of different grades. The system performance of the SURF features are also analyzed by comparing the results with SIFT features using different cluster sizes. The results show 90.15% accuracy in detection of prostate cancer images using SURF features with 75 clusters for k-mean clustering. The results showed higher sensitivity for SURF based BoW classification compared to SIFT based BoW.

  10. Imaging polarimetry of the fogbow: polarization characteristics of white rainbows measured in the high Arctic.

    Science.gov (United States)

    Horváth, Gábor; Hegedüs, Ramón; Barta, András; Farkas, Alexandra; Åkesson, Susanne

    2011-10-01

    The knowledge on the optics of fogbows is scarce, and their polarization characteristics have never been measured to our knowledge. To fill this gap we measured the polarization features of 16 fogbows during the Beringia 2005 Arctic polar research expedition by imaging polarimetry in the red, green and blue spectral ranges. We present here the first polarization patterns of the fogbow. In the patterns of the degree of linear polarization p, fogbows and their supernumerary bows are best visible in the red spectral range due to the least dilution of fogbow light by light scattered in air. In the patterns of the angle of polarization α fogbows are practically not discernible because their α-pattern is the same as that of the sky: the direction of polarization is perpendicular to the plane of scattering and is parallel to the arc of the bow, independently of the wavelength. Fogbows and their supernumeraries were best seen in the patterns of the polarized radiance. In these patterns the angular distance δ between the peaks of the primary and the first supernumerary and the angular width σ of the primary bow were determined along different radii from the center of the bow. δ ranged between 6.08° and 13.41°, while σ changed from 5.25° to 19.47°. Certain fogbows were relatively homogeneous, meaning small variations of δ and σ along their bows. Other fogbows were heterogeneous, possessing quite variable δ- and σ-values along their bows. This variability could be a consequence of the characteristics of the high Arctic with open waters within the ice shield resulting in the spatiotemporal change of the droplet size within the fog.

  11. Scoping of Flood Hazard Mapping Needs for Merrimack County, New Hampshire

    Science.gov (United States)

    2006-01-01

    the Merrimack River. This area is currently zone A and is zoned as industrial by the town and has had a lot of development. • On panel 2, a...detailed study is needed along the tributary to Bow Bog Brook from I-93 to Bow Bog Brook. This area is currently zone A and is zoned as industrial by the...needs a detailed study from Shindagan Brook to the Tannery Pond (Stone Bridge Road). • On panel 11, a detailed study is needed from Tannery Pond

  12. Alternative learning strategies as part of the educational process

    Science.gov (United States)

    Swartz, Ronald

    The terrible dissension which has endured for so many centuries is a striking lesson teaching us mutually to forgive our errors; dissension is the great evil of mankind and toleration is its only remedy we should all mutually tolerate each other, because we are all weak, inconsistent, a prey to change and error. Should a reed, bowed into the mud by the wind say to the neighboring reed, bowed in the opposite direction: Creep in my fashion, wretch, or I'll send in a request to have you uprooted and burned? (Voltaire, 1764/1962, pp. 487-489).Received: 7 May 1980; Revised: 16 April 1981;

  13. Mirror waves and mode transition observed in the magnetosheath by Double Star TC-1

    Directory of Open Access Journals (Sweden)

    J. Du

    2009-01-01

    Full Text Available The Double Star TC-1 magnetosheath pass on 26 February 2004 is used to investigate magnetic field fluctuations. Strong compressional signatures which last for more than an hour have been found near the magnetopause behind a quasi-perpendicular bow shock. These compressional structures are most likely mirror mode waves. There is a clear wave transition in the magnetosheath which probably results from the change of the interplanetary magnetic field (IMF cone angle. The wave characteristics in the magnetosheath are strongly controlled by the type of the upstream bow shock.

  14. Massive runaway stars in the Large Magellanic Cloud

    Science.gov (United States)

    Gvaramadze, V. V.; Kroupa, P.; Pflamm-Altenburg, J.

    2010-09-01

    The origin of massive field stars in the Large Magellanic Cloud (LMC) has long been an enigma. The recent measurements of large offsets (˜ 100 km s-1) between the heliocentric radial velocities of some very massive (O2-type) field stars and the systemic LMC velocity provides a possible explanation of this enigma and suggests that the field stars are runaway stars ejected from their birthplaces at the very beginning of their parent cluster's dynamical evolution. A straightforward way to prove this explanation is to measure the proper motions of the field stars and to show that they are moving away from one of the nearby star clusters or OB associations. This approach is, however, complicated by the long distance to the LMC, which makes accurate proper motion measurements difficult. We used an alternative approach for solving the problem (first applied for Galactic field stars), based on the search for bow shocks produced by runaway stars. The geometry of detected bow shocks would allow us to infer the direction of stellar motion, thereby determining their possible parent clusters. In this paper we present the results of a search for bow shocks around six massive field stars that have been proposed as candidate runaway stars. Using archival Spitzer Space Telescope data, we found a bow shock associated with one of our programme stars, the O2 V((f*)) star BI 237, which is the first-ever detection of bow shocks in the LMC. Orientation of the bow shock suggests that BI 237 was ejected from the OB association LH 82 (located at ≃ 120 pc in projection from the star). A by-product of our search is the detection of bow shocks generated by four OB stars in the field of the LMC and an arc-like structure attached to the candidate luminous blue variable R81 (HD 269128). The geometry of two of these bow shocks is consistent with the possibility that their associated stars were ejected from the 30 Doradus star-forming complex. We discuss implications of our findings for the

  15. 細長体理論による船体運動の解析(その3) : 前進速度の影響を考慮したrational strip theory

    OpenAIRE

    足達, 宏之; Hiroyuk, ADACHI; 船舶技術研究所推進性能部

    1980-01-01

    When a ship is moving through regular waves, the motion of the ship may be treated by the slender-ship theory. The consistent expansion of the slender-ship theory in the bow near field, where the distance from the bow is 0(ε^) with e being the slenderness parameter of ship, can be performed under the high frequency motion assumtion. For such situation the forward speed effect will be included in the free surface condition for the lowest order unsteady motion potential. Thus the governing boun...

  16. Large capacity multi-float configurations for the wave energy converter M4 using a time-domain linear diffraction model

    OpenAIRE

    Stansby, Peter; Carpintero Moreno, Efrain; Stallard, Timothy

    2017-01-01

    The moored three-float line absorber WEC M4 has been developed to optimise power capture through experiments and linear diffraction modelling. With the progression down wave from small to medium to large floats, the device heads naturally into the wave direction. The bow and mid floats are rigidly connected by a beam and a beam from the stern float is connected to the hinge point above the mid float for power take off (PTO). Increasing the bow to mid float spacing to be more than 50% greater ...

  17. Influence of basin-scale and mesoscale physical processes on biological productivity in the Bay of Bengal during the summer monsoon

    Digital Repository Service at National Institute of Oceanography (India)

    Muraleedharan, K.R.; Jasmine, P.; Achuthankutty, C.T.; Revichandran, C.; DineshKumar, P.K.; Anand, P.; Rejomon, G.

    of temperature, salinity and density (Fig. 5a) were bowed down to depths of 50?100 m, increasing the thickness of the mixed layer. The warm (29 C176C), low salinity (C2433.5) surface water resulted in sea level elevation of 5?15 cm in the central BoB above...). In the warm gyre region, the isopycnals were bowed down because of the clockwise circulation, deepening the MLD to >70 m and the thermocline to >190 m (Fig. 5a). The freshwater-induced stratification impedes the advection of nutrients in to the euphotic zone...

  18. Crystal structure of acetyl 29-methyl-29-methylidene-D:C-friedoolean-8-en-3beta-ol.

    Science.gov (United States)

    Honda, Chie; Kamisako, Wasuke; Miwa, Yoshihisa

    2003-03-01

    Acetyl 29-methyl-29-methylidene-D:C-friedoolean-8-en-3beta-o1 (2), derived from bryonolic acid (D:C-friedoolean-8-en-3beta-ol-29-oic acid) (1), was crystallographically analyzed. Rings A-E of 2 adopted chair, half-chair, half-chair, boat (with bow and stern at C-13 and C-16), boat (with bow and stem at C-19 and C-22) conformations, respectively. Good agreement was found between the structures from X-ray crystallography and that from MM2 calculations.

  19. Heavy metal accumulation in a flow restricted, tropical estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Balachandran, K.K.; Laluraj, C.M.; Nair, M.; Joseph, T.; Sheeba, P.; Venugopal, P.

    flow. The ox-bow shape of the lake (Soman, 1997) has a strong bearing on the tidal modulations and flushing characteristics, which eventu- ally govern the estuarine water balance and the biological dynamics. 2. Methods Surficial sediments were collected... effect, around Kadakkara, situated midway between Cochin and Azhikode’’. The geomor- phology (ox-bow shape) of the estuary and meandering flow can induce the formation of perennially-undulating water bodies or null zones. The weak flushing could result...

  20. River inputs and organic matter fluxes in the northern Bay of Bengal: Fatty acids

    Digital Repository Service at National Institute of Oceanography (India)

    Reemtsma, T.; Ittekkot, V.; Bartsch, M.; Nair, R.R.

    period. It was ascribed to the flooding of ox-bow lakes in the delta and the drainage of degraded organic material deposited there. 3.2. Temporal development of terri genous and marine fatty acid fluxes 90. 60' 'E v 30' B00' soo. 400" 200' a... with falling water. A comparable mechanism, the inter- mediate storage within ox-bow lakes in the flood plains, was suggested for the Ganges (It- tekkot et al., 1986). The marine fatty acid flux has an additional third maximum in July (Fig. 5b, No. 8...

  1. Nature of suspended particles in hydrothermal plume at 3°40'N Carlsberg ridge: A comparison with deep oceanic suspended matter

    Digital Repository Service at National Institute of Oceanography (India)

    Ray, D.; Babu, E.V.S.S.K.; SuryaPrakash, L.

    the plume. Concentration of particulate Mn is similar to that reported in Gorda Ridge plumes (0.76–1.66 nmol/l)3, but higher than Carlsberg event plume (0.46 nmol/l)9 or Rain- bow plume particulates (<0.5 nmol/l)4. Dissolved Mn in hydrothermal plume...-Sea Res. II, 1998, 45, 2637–2664. 4. Edmond, H. N. and German, C. R., Particle geochemistry of Rain- bow hydrothermal plume; Mid-Atlantic Ridge. Geochim. Cosmo- chim. Acta, 2004, 68, 759–772. 5. Lerche, D. and Nozaki, Y., Rare earth elements of sinking...

  2. A new species of Litarachna Walter, 1925 (Acari: Hydrachnidia) from the West Indian Coast, with a discussion on the diversity of the family Pontarachnidae Koenike, 1910

    Digital Repository Service at National Institute of Oceanography (India)

    Pesic, V.; Chatterjee, T.; Ingole, B.S.; Velip, D.; Pavicevic, A.

    bowed, not arrow-shaped and fused with postgenital sclerite, genital field less elongated (L/W ratio 1.6). Male: two pairs of wheel-like acetabula, posterior to the genital field, very large with many radiating spokes (maximum diameter L 19 µm...). Genital field L/W 51 (51)/32 (32). Pregenital and postgenital sclerite strongly bowed and fused. Between the posterior apodemes of the fourth coxal plates a pair of glandularia-like structures and a pair of small platelets with (according to Wiles et al...

  3. Airfoil structure

    Science.gov (United States)

    Frey, Gary A.; Twardochleb, Christopher Z.

    1998-01-01

    Past airfoil configurations have been used to improve aerodynamic performance and engine efficiencies. The present airfoil configuration further increases component life and reduces maintenance by reducing internal stress within the airfoil itself. The airfoil includes a chord and a span. Each of the chord and the span has a bow being summed to form a generally "C" configuration of the airfoil. The generally "C" configuration includes a compound bow in which internal stresses resulting from a thermal temperature gradient are reduced. The structural configuration reduces internal stresses resulting from thermal expansion.

  4. Alternative Inspection Methods for Single Shell Tanks

    Energy Technology Data Exchange (ETDEWEB)

    Peters, Timothy J.; Alzheimer, James M.; Hurley, David E.

    2010-01-19

    This document was prepared to provide evaluations and recommendations regarding nondestructive evaluation methods that might be used to determine cracks and bowing in the ceiling of waste storage tanks on the Hanford site. The goal was to determine cracks as small as 1/16 in. wide in the ceiling, and bowing as small as 0.25 in. This report describes digital video camera methods that can be used to detect a crack in the ceiling of the dome, and methods for determining the surface topography of the ceiling in the waste storage tanks to detect localized movements in the surface. A literature search, combined with laboratory testing, comprised this study.

  5. A probable new type of osteopenic bone disease

    Energy Technology Data Exchange (ETDEWEB)

    Widhe, Torulf L. [Department of Orthopaedics, Huddinge University Hospital (Sweden)

    2002-06-01

    A probable new type of osteopenic bone disease in two sisters and one female cousin is described. In infancy, the radiological findings were osteopenia, coxa vara, periosteal cloaking, bowing of the long bones, and flaring of the metaphyses. During growth, spinal pathology developed with compression of the vertebral bodies and scoliosis in one girl and kyphosis in another. All three children had genu valgum and two developed severe S-shaped bowing of the tibiae. Growth was stunted. Inheritance of this disorder is probably recessive. Type I and III collagen biosynthesis was normal. This condition is probably a hitherto undescribed form of osteogenesis imperfecta type III or a new bone disease. (orig.)

  6. Accuracy of Manufacturing the Scythian Arrow and Its Influence on the Arrow’s Ballistic Parameters

    Directory of Open Access Journals (Sweden)

    Aleksey V. Korobeinikov

    2014-03-01

    Full Text Available Analysis of Scythian arrowheads discovered in the area near the Severniy Donets River showed that they might belong to one batch, that is, they may probably have come from the same quiver. As archeologists date the findings back to the period of VII-IV centuries B.C., for this entire period, the Scythian bow did not have any substantial changes in its design. Due to the fact that the analysis involved both combat-purpose and hunting arrows, we have sufficient grounds to believe that the Scythians might have had a versatile bow to help them perform all kinds of combat and everyday tasks.

  7. Heat transfer unit and method for prefabricated vessel

    Energy Technology Data Exchange (ETDEWEB)

    Tamburello, David A.; Kesterson, Matthew R; Hardy, Bruce J.

    2017-11-07

    Vessel assemblies, heat transfer units for prefabricated vessels, and methods for heat transfer prefabricated vessel are provided. A heat transfer unit includes a central rod, and a plurality of peripheral rods surrounding the central rod and connected to the central rod. The plurality of peripheral rods are movable between a first collapsed position and a second bowed position, wherein in the second bowed position a midpoint of each of the plurality of peripheral rods is spaced from the central rod relative to in the first position. The heat transfer unit further includes a heat transfer element connected to one of the plurality of peripheral rods.

  8. Revisiting the round bottom flask rainbow experiment

    Science.gov (United States)

    Selmke, Markus; Selmke, Sarah

    2018-01-01

    A popular demonstration experiment in optics uses a round-bottom flask filled with water to project a circular rainbow on a screen with a hole through which the flask is illuminated. We show how the vessel's wall shifts the first- and second-order bows towards each other and consequently reduces the width of Alexander's dark band. We address the challenge this introduces in observing Alexander's dark band, and explain the importance of a sufficient distance between the flask and the screen. The wall-effect also introduces a splitting of the bows that can easily be misinterpreted.

  9. Le parler Buja des Yambuli (Bantou C.37) | Mangulu | Annales ...

    African Journals Online (AJOL)

    C'est ce qui s'est dégagé de la confrontation entre le parler des Yambuli et celui des Yaliambi (Secteur de l'Itimbiri). L'egbuta (Motingea 2002a) parlé dans la chefferie de BowE2la-BomEngE près d'Ibembo (Territoire d'Aketi) s'écarte encore davantage de ces deux. Mots-clés: bujá; Bumba; Yambuli; Molua; Kwanja; Ebonda ...

  10. Active Visual SLAM with Exploration for Autonomous Underwater Navigation

    Science.gov (United States)

    2012-01-01

    cross-track image overlap for a ∼45◦ horizontal camera field of view (in water). Occasionally the vehicle was commanded to swim back toward the bow...Part 1. Rife, J., and S. Rock (2001), Visual tracking of jellyfish in situ, Proceedings of the Inter- national Conference on Image Processing, 1, 289–292

  11. 14 CFR 25.535 - Auxiliary float loads.

    Science.gov (United States)

    2010-01-01

    ... float to the radius of gyration in roll. (c) Bow loading. The resultant limit load must be applied in... follows: EC28SE91.043 where— ρ=mass density of water (slugs/ft.2); V=volume of float (ft.2); C x...

  12. CASE REPORT CASE R Leri-Weill dyschondrosteosis: An under ...

    African Journals Online (AJOL)

    2009-12-03

    Dec 3, 2009 ... X and Y chromosomes in the pseudo-autosomal region. Heterozygous carriers of SHOX mutations ... features of Madelung deformity: bowing and shortening of the distal radius, widening of the distal radial-ulnar joint, and triangulation of the distal radial epiphysis, producing an ulnar slant to the articular.

  13. Semantic Image Based Geolocation Given a Map (Author’s Initial Manuscript)

    Science.gov (United States)

    2016-09-01

    retrieved images using geometric constraints [19]. The improvements of this methods include learning better vocabularies, develop- ing better...compute probabilities of building identities for image regions labelled as buildings in the image by semantic segmentation algorithm . Figure 3...meta information associated with the map and a single view reconstruction. This enhanced labeling then improves the BoW retrieval strategies in case

  14. Small Vocabulary with Saliency Matching for Video Copy Detection

    DEFF Research Database (Denmark)

    Ren, Huamin; Moeslund, Thomas B.; Tang, Sheng

    2013-01-01

    of vocabulary. BoW descriptors under a small vocabulary can be both robust and efficient, while keeping high recall rate compared with large vocabulary. However, the high false positives exists in small vocabulary also limits its application. To address this problem in small vocabulary, we propose a novel...

  15. Studying friction while playing the violin: exploring the stick-slip phenomenon.

    Science.gov (United States)

    Casado, Santiago

    2017-01-01

    Controlling the stick-slip friction phenomenon is of major importance for many familiar situations. This effect originates from the periodic rupture of junctions created between two rubbing surfaces due to the increasing shear stress at the interface. It is ultimately responsible for the behavior of many braking systems, earthquakes, and unpleasant squeaky sounds caused by the scratching of two surfaces. In the case of a musical bow-stringed instrument, stick-slip is controlled in order to provide well-tuned notes at different intensities. A trained ear is able to distinguish slight sound variations caused by small friction differences. Hence, a violin can be regarded as a perfect benchmark to explore the stick-slip effect at the mesoscale. Two violin bow hairs were studied, a natural horse tail used in a professional philharmonic orchestra, and a synthetic one used with a violin for beginners. Atomic force microscopy characterization revealed clear differences when comparing the surfaces of both bow hairs, suggesting that a structure having peaks and a roughness similar to that of the string to which both bow hairs rubbed permits a better control of the stick-slip phenomenon.

  16. Liquid Metal Machine Triggered Violin-Like Wire Oscillator.

    Science.gov (United States)

    Yuan, Bin; Wang, Lei; Yang, Xiaohu; Ding, Yujie; Tan, Sicong; Yi, Liting; He, Zhizhu; Liu, Jing

    2016-10-01

    The first ever oscillation phenomenon of a copper wire embraced inside a self-powered liquid metal machine is discovered. When contacting a copper wire to liquid metal machine, it would be swallowed inside and then reciprocally moves back and forth, just like a violin bow. Such oscillation could be easily regulated by touching a steel needle on the liquid metal surface.

  17. Modelling Analysis of Echo Signature and Target Strength of a Realistically Modelled Ship Wake for a Generic Forward Looking Active Sonar

    NARCIS (Netherlands)

    Schippers, P.

    2009-01-01

    The acoustic modelling in TNO’s ALMOST (=Acoustic Loss Model for Operational Studies and Tasks) uses a bubble migration model as realistic input for wake modelling. The modelled bubble cloud represents the actual ship wake. Ship hull, propeller and bow wave are the main generators of bubbles in the

  18. Religion and the Pan-African ideal

    African Journals Online (AJOL)

    . The general thrust of Moten's argument is that. Islamic society is capable of .... at a time when the revolutionary dream seemed fanciful and freedom of opinion was denied in the Third World. The Iranian revolution bowed to the will of the ...

  19. Timber seasoning and density characterstics of Cordia alliodora ...

    African Journals Online (AJOL)

    Shrinkage values of the timber at oven dry (0%) MC compared at 12% MC increased by about 1.7 times. Slight seasoning defects such as cup, bow, twist, end split and checks were observed. In general, the species revealed good timber properties and qualities. Therefore, the species has to be grown and well managed, ...

  20. TNO at TRECVID 2013: Multimedia Event Detection and Instance Search

    NARCIS (Netherlands)

    Bouma, H.; Azzopardi, G.; Spitters, M.M.; Wit, J.J. de; Versloot, C.A.; Zon, R.W.L. van der; Eendebak, P.T.; Baan, J.; Hove, R.J.M. ten; Eekeren, A.W.M. van; Haar, F.B. ter; Hollander, R.J.M. den; Huis, R.J. van; Boer, M.H.T. de; Antwerpen, G. van; Broekhuijsen, B.J.; Daniele, L.M.; Brandt, P.; Schavemaker, J.G.M.; Kraaij, W.; Schutte, K.

    2013-01-01

    We describe the TNO system and the evaluation results for TRECVID 2013 Multimedia Event Detection (MED) and instance search (INS) tasks. The MED system consists of a bag-of-word (BOW) approach with spatial tiling that uses low-level static and dynamic visual features, an audio feature and high-level

  1. Hamburgian weapon delivery technology: a quantitative comparative approach

    DEFF Research Database (Denmark)

    Riede, Felix

    2010-01-01

    cran). Numerous studies have addressed the question of whether these points tipped arrows fired from bows, darts launched with the help of spear-throwers, or some other projectile delivery weapon. This paper approaches the question of Hamburgian weapon delivery technology from a quantitative...

  2. Cultural Resources Survey of Five Mississippi River Revetment Items.

    Science.gov (United States)

    1985-08-01

    molasses. Both were placed in a revolving sieve, and the molasses was driven out as the sieve spun at 2000 revolutions per minute (DeBow 1851:89). This...Conseil de la vie Francaise en Amerique, Quebec. ’ Barber, Edwin Atlee 1902 Pottery and Porcelain of the United States. G.P. Putnam, New York. Baugher

  3. Sports, Physical Activity and Recreation in Early American History.

    Science.gov (United States)

    Ballou, Ralph B.

    Sports and physical recreation activities have been part of American life since the days of the early settlers. Although the settlers were faced with problems of survival, accounts of life in the colonies in the 1600's carry mention of bowling in the streets, play with bows and arrows, and ice skating. Other activities to gain popularity before…

  4. 32 CFR 552.129 - Requirements for carrying and use.

    Science.gov (United States)

    2010-07-01

    ... RESERVATIONS AND NATIONAL CEMETERIES REGULATIONS AFFECTING MILITARY RESERVATIONS Control of Firearms... legally authorized to possess firearms, ammunition, knives (with blades longer than 3 inches), bows and... having the weapon repaired: From quarters by the most direct route to approved range or to the location...

  5. Exploring the Relevance and Quality of the VaRemba Initiation ...

    African Journals Online (AJOL)

    Of much interest to the educator, were behaviour changes apparent in students soon after .... elderly woman. Initiation is a bridging course between. • boyhood and manhood. The course is an initiation from girlhood to. • womanhood. The removal of the foreskin of the male ... bow, or lie on the ground in the presence of.

  6. Classroom

    Indian Academy of Sciences (India)

    float in a baby bathtub? Would you be able to name the Sicilian genius who transformed his bathtub to one of the most advanced laboratories and whose ..... early part of the 20th century. Bowing to market forces we are. It is indeed remarkable that. Archimedes posed and solved a hydrostatic problem of eternal interest to.

  7. Rupture Analysis of Oil Tankers in a Side Collision

    DEFF Research Database (Denmark)

    Simonsen, Bo Cerup; Wierzbicki, Tomasz

    1996-01-01

    A closed form solution to the problem of initiation and steady state wedge cutting through a ductile metal plate is presented. The considered problemis an idealization of the cutting process of a sharp raked bow of a ship into a deck of a stricken ship.A new kinematic model is proposed...

  8. 1-Benzoyl-3,6-diphenyl-1,4-dihydro-1,2,4,5-tetra-zine.

    Science.gov (United States)

    Xu, Feng; Yang, Zhen-Zhen; Chen, Xiao-Fang; Zheng, Wen-Xiu

    2010-09-30

    In the title compound, C(21)H(16)N(4)O, the central tetra-zine ring adopts an unsymmetrical boat conformation with the two N atoms as the bow and stern. The crystal packing is stabilized by inter-molecular N-H-O hydrogen bonds.

  9. 1-Benzoyl-3,6-diphenyl-1,4-dihydro-1,2,4,5-tetra­zine

    Science.gov (United States)

    Xu, Feng; Yang, Zhen-Zhen; Chen, Xiao-Fang; Zheng, Wen-Xiu

    2010-01-01

    In the title compound, C21H16N4O, the central tetra­zine ring adopts an unsymmetrical boat conformation with the two N atoms as the bow and stern. The crystal packing is stabilized by inter­molecular N—H—O hydrogen bonds. PMID:21587635

  10. 77 FR 40802 - Seaway Regulations and Rules: Periodic Update, Various Categories

    Science.gov (United States)

    2012-07-11

    ... vessels 100 m or less. In section 401.15, ``Stern anchors'', the Seaway entities are requiring vessels of... barge unit greater than 125 m in overall length be equipped with a stern anchor. Several changes to the... wire line is used shall be powered. The line shall lead astern from the break of the bow through a...

  11. Extreme value prediction of the wave-induced vertical bending moment in large container ships

    DEFF Research Database (Denmark)

    Andersen, Ingrid Marie Vincent; Jensen, Jørgen Juncher

    2015-01-01

    Container ships of today are becoming increasingly larger. The increased ship size implies lower natural hull frequencies which influence the hull girder response in waves. The large bow and stern flare of container ships make them vulnerable to whipping-induced loads, and whipping loads may...

  12. Dissolved aluminium in the surface microlayer of the eastern Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Narvekar, P.V.; Singbal, S.Y.S.

    of the sampler (Singbal and Narvekar, 1988). Before sampling, the sampler was cleaned with 25% hydrochloric acid followed by thorough rinsings with fresh water and deionised water. The sampler was operated from the bow of the ship only in the up...

  13. Spatial variations in time-integrated plankton metabolic rates in Sagami Bay using triple oxygen isotopes and O2:Ar ratios

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.S.S.; Abe, O.; Saino, T.

    2006 in Sagami Bay, central Japan. Bubble-free surface waters were collected through the ship’s seawater-intake supply line, which was located at the bow at a nominal depth of 4 m. Dissolved gases were extracted using a 12-cm-long, hollow...

  14. 75 FR 49709 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Science.gov (United States)

    2010-08-13

    ... launched from the stern of a vessel and will survey the seafloor close to the vessel. The vessel will... unlikely to occur unless bow-riding odontocetes are exposed to airgun pulses much stronger than 180 dB re 1...

  15. 50 CFR 216.24 - Taking and related acts incidental to commercial fishing operations by tuna purse seine vessels...

    Science.gov (United States)

    2010-10-01

    ... from the backdown channel apex to the stern tiedown point. The dolphin safety panel must consist of... that begins at the outboard end of the last bow bunch pulled and continues to at least two-thirds the distance from the backdown channel apex to the stern tiedown point. (7) Experimental fishing operations...

  16. Sea truth validation of sea WiFS ocean colour sensor in the coastal waters of the eastern Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Desa, E.S.; Suresh, T.; Matondkar, S.G.P.; Desa, E.

    effect of the ship on the downwelling irradiance field leading to errors of 1 ? 2%, for clear skies with the sun within ? 45 degrees of the beam of the ship. Errors of up to 10% occur if the sun is off the bow or stern of the ship and wavelength...

  17. 15 (No. 2)

    African Journals Online (AJOL)

    mwakagugu

    Diagnostic casts were articulated with face-bow transfer and surgical template prepared with clearauto polymerizing resin. Surgical template was inserted in the .... Belser UC, Mericske-Stern R, Bernard JP,. Taylor TD. Prosthetic management of the partially dentate patient with fixed implant restorations Clin Oral Impl Res ...

  18. Estimation of bulk transfer coefficient for latent heat flux (Ce)

    Digital Repository Service at National Institute of Oceanography (India)

    Sadhuram, Y.

    Coefficients in Diabatic Conditions’, Bow~dary-Layer Meteo- rol. 8, 465-474. Murakami. T., Nakazowa. T., and He, T.: 1984, ‘On the 40-50 Day Oscillations During the Monsoon During the Northern Hemisphere Summer. Part II: Heat and Moisture Budget’, J. Mereoi...

  19. SWIFTER THAN EAGLES

    African Journals Online (AJOL)

    combination of machine gun fire and accurate bombing of the port bow the Ju 86 was able to head the Watussi for Cape Town but was unable to prevent her crew .... stern at an altitude of 20 feet scoring direct hits with three of his four 250 pound bombs and stopping the Prosperina in her tracks, allowing an RAF Beaufort to ...

  20. 46 CFR 69.111 - Between-deck tonnage.

    Science.gov (United States)

    2010-10-01

    ... complete deck runs in a continuous line from stem to stern, the line of the uppermost complete deck is the... different levels from stem to stern, the line of the uppermost complete deck is the longitudinal line of the... successively “1”, “2”, and so forth beginning at the bow. (4) Multiply the even numbered breadths by four and...

  1. Observations of trace gases and aerosols over the Indian Ocean during the monsoon transition period

    Digital Repository Service at National Institute of Oceanography (India)

    Mandal, T.K.; Khan, A.; Ahammed, Y.N.; Tanwar, R.S.; Parmar, R.S.; Zalpuri, K.S.; Gupta, P.K.; Jain, S.L.; Singh, R.; Mitra, A.P.; Garg, S.C.; Suryanarayana, A.; Murty, V.S.N.; DileepKumar, M.; Shepherd, A.J.

    .e., flushing the air through glass samplers. The glass sam- plers were flushed initially for ten minutes. After thorough flushing with ambient air, the air sam- ple was collected above atmospheric pressure (to avoid contamination due to leakage) at the bow...

  2. Reactivation of precambrian faults on the southwestern continental margin of India: Evidence from gravity anomalies

    Digital Repository Service at National Institute of Oceanography (India)

    Subrahmanyam, V.; Ramana, M.V.; Rao, D.G.

    reveal a gentle gradient of the sea bed from the nea~hore.(20 m) down to water depths of 100 m. Relatively steep gradients with Localized shoals are more ~rom~ent between 100 m and 1600 m. The figures also show an outward bowing (bight) in the 50...

  3. 1-Benzoyl-3,6-diphenyl-1,4-dihydro-1,2,4,5-tetrazine

    Directory of Open Access Journals (Sweden)

    Wen-Xiu Zheng

    2010-10-01

    Full Text Available In the title compound, C21H16N4O, the central tetrazine ring adopts an unsymmetrical boat conformation with the two N atoms as the bow and stern. The crystal packing is stabilized by intermolecular N—H—O hydrogen bonds.

  4. Bacterial domination over Archaea in ammonia oxidation in a monsoon-driven tropical estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Vipindas, P.V.; Anas, A.; Jasmin, C.; Lallu, K.R.; Fausia, K.H.; Balachandran, K.K.; Muraleedharan, K.R.; Nair, S.

    effluents [18] and formation of perennially undulating water bodies or null zones due to its geomorphology (ox-bow shaped) and meandering flow [19-21]. High nutrient loading during 6 monsoon season has been earlier documented not only in CE [11...

  5. 33 CFR 207.420 - Chicago River, Ill.; Sanitary District controlling works, and the use, administration, and...

    Science.gov (United States)

    2010-07-01

    ..., have at least one line out when entering the lock and shall be moored in the lock with two bow and two stern lines, which shall lead forward and aft at each end of the vessel or tow. When the gates are...

  6. Geologic implications of gas hydrates in the offshore of India: Results of the National Gas Hydrate Program Expedition 01

    Digital Repository Service at National Institute of Oceanography (India)

    Collett, T.S.; Boswell, R.; Cochran, J.R.; Kumar, P.; Lall, M.; Mazumdar, A.; Ramana, M.V.; Ramprasad, T.; Riedel, M.; Sain, K.; Sathe, A.V.; Vishwanath, K.; NGHP Expedition 01 Scientific Party

    hours and assisted by mammal watchers posted at both the bow and stern of the ship. No mammals were observed during any of the VSP operations. 2.4.5. NGHP-01 operational summary For organizational purposes, NGHP-01 was divided into five operational...

  7. VTOL/STOL visual study

    Science.gov (United States)

    Lewandowski, F. P.

    1980-01-01

    The development of data bases and real time techniques to improve the realism of sea state, bow and stern wake, and ship motion is addressed. This system was designed for use with the Vertical Motion Simulator to perform basic studies on VTOL/STOL aircraft.

  8. 77 FR 32071 - Seaway Regulations and Rules: Periodic Update, Various Categories

    Science.gov (United States)

    2012-05-31

    ...'', the SLSDC is addressing the use of wire lines on vessels 100 m or less. In section 401.15, ``Stern... with a stern anchor. Several changes to the Seaway Navigation section are being proposed. The Seaway... line shall lead astern from the break of the bow through a closed chock to suitable bitts on deck for...

  9. 77 FR 25829 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

    Science.gov (United States)

    2012-05-01

    ... be towed at a distance of ~30 feet (ft, or 10 m) from the stern at 6 ft (2 m) depth, which is... (7 m) from the stern at 3 ft (1 m) depth, also remotely adjustable when needed. The source vessels... seen by observers on active seismic vessels, occasionally at close distances (e.g., bow riding). Marine...

  10. A finite element simulation of tidal circulation in the Gulf of Kutch, India

    Digital Repository Service at National Institute of Oceanography (India)

    Unnikrishnan, A.S.; Luick, J.L.

    Columbia (Visser, Bow- man, & Crawford, 1990), and the Gulf of Carpentaria in northern Australia (Wolanski, 1993). 4. Conclusions The results of a 1-month model run were analysed to separate M 2 ,S 2 ,K 1 ,O 1 and M 4 , and compared with observations...

  11. 75 FR 19880 - Safety Zone; BW PIONEER at Walker Ridge 249, Outer Continental Shelf FPSO, Gulf of Mexico

    Science.gov (United States)

    2010-04-16

    ... shuttle tanker will connect its bow to the FPSO BW PIONEER and its stern to an attendant tug that will.... Basis and Purpose The Coast Guard is establishing a safety zone of 500 meters around the stern of the...) around the stern of the FPSO when it is moored to the turret buoy is a safety zone. If the FPSO detaches...

  12. 33 CFR 183.3 - Definitions.

    Science.gov (United States)

    2010-07-01

    ..., measured from end to end over the deck excluding sheer, and measured parallel to the centerline. Bow sprits... transom (stern) at the aft end. For the purposes of this definition, the topmost line in a boat's side is... at the stern of a boat projecting or facing aft. The upper boundary of the transom is the line...

  13. Innovative technologies to accurately model waves and moored ship motions

    CSIR Research Space (South Africa)

    van der Molen, W

    2010-09-01

    Full Text Available at the bow and one at the stern (see Figure 6). Two mirrors are placed at 45°, extending from the quay above the metal plates, and two video cameras are placed alongside the ship at a distance of about 10 m (model scale) to focus on the metal strips...

  14. 33 CFR 165.515 - Safety Zone: Cape Fear River, Wilmington, North Carolina.

    Science.gov (United States)

    2010-07-01

    ...′54″ N 77°57′06″ W (2) The safety zone boundary can be described as follows: starting at the stern of... moorings, down along the east bank of the Cape Fear River to the bow of the tug CAPTAIN JOHN TAXIS Memorial... Cape Fear River to the stern of the Battleship USS NORTH CAROLINA. (b) Definitions. The designated...

  15. Long-term changes in microbial and biochemical parameters in the Central Indian Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, C.; Nath, B.N.; Sharma, R.; LokaBharathi, P.A.; Dalal, S.G.

    of the sediment plume. Sediment samples were collected with a USNEL- type box corer of 50 x 50 x 50 cm dimensions. Although Bett et al. (1994) and Shirayama and Fukushima (1995) have indicated the inherent problem of bow wave effects with box core sampling, we...

  16. An interactive graphical system of XBT data quality control and visualization

    Digital Repository Service at National Institute of Oceanography (India)

    Pankajakshan, T.; Ghosh, A.K.; Sarupria, J.S.; Gopalakrishna, V.V.

    and correcting/flagging of features caused by wire stretch, wire break, bowing and nub in the mixed layer. Provision is given to compare individual XBT profiles with neighboring stations and also with 1 degree x 1-degree monthly climatologies. Quality flags...

  17. Numerical prediction of slamming loads

    DEFF Research Database (Denmark)

    Seng, Sopheak; Jensen, Jørgen J; Pedersen, Preben T

    2012-01-01

    It is important to include the contribution of the slamming-induced response in the structural design of large vessels with a significant bow flare. At the same time it is a challenge to develop rational tools to determine the slamming-induced loads and the prediction of their occurrence. Today i...

  18. (3.0. Akpede, FWACP, FMCP, Department of Paediatrics, EA ...

    African Journals Online (AJOL)

    2001-11-01

    Nov 1, 2001 ... NUTRITIONAL RICKETS IN YOUNG NIGERIAN CHILDREN IN THE SAHEL SAVANNA*. (3.0. Akpede, FWACP ... children of Moslem families (p <0.05) and children whose mothers were full-time housewives, unskilled or traders ... fever and difficult/rapid breathing), history of bowing of the legs in the child's ...

  19. 76 FR 45609 - Notice of Availability of the Draft Environmental Impact Statement for the Gateway West 230/500...

    Science.gov (United States)

    2011-07-29

    ..., Caribou-Targhee National Forest. Donald A. Simpson, Wyoming State Director. BILLING CODE 4310-22-P ... electric transmission line from the proposed Windstar Substation near the Dave Johnston Power Plant at... units of the National Forest System: 7 miles in the Douglas Ranger District of the Medicine Bow-Routt...

  20. The Peters' plus syndrome: a review

    NARCIS (Netherlands)

    Maillette de Buy Wenniger-Prick, Liesbeth J. J. M.; Hennekam, Raoul C. M.

    2002-01-01

    Peters' plus syndrome is an infrequently described entity that combines anomalies in the anterior chamber of the eye with other multiple congenital anomalies, and a developmental delay. Major symptoms are extremely variable anterior chamber anomalies, cupid bow of the upper lip, cleft lip and