Sample records for region axially deformed

  1. Dynamic control of knee axial deformities

    E. E. Malyshev


    Full Text Available The authors have evaluated the clinical examination of the patients with axial malalignments in the knee by the original method and device which was named varovalgometer. The measurements were conducted by tension of the cord through the spina iliaca anterior superior and the middle of the lower pole of patella. The deviation of the center of the ankle estimated by metal ruler which was positioned perpendicular to the lower leg axis on the level of the ankle joint line. The results of comparison of our method and computer navigation in 53 patients during the TKA show no statistically significant varieties but they differ by average 5° of valgus in clinical examination in comparison with mechanical axis which was identified by computer navigation. The dynamic control of axial malalignment can be used in clinical practice for estimation of the results of treatment of pathology with axial deformities in the knee; for the control of reduction and secondary displacement of the fractures around the knee; for assessment of instability; in planning of correctional osteotomies and intraoperative control of deformity correction; for estimation of Q angle in subluxation and recurrent dislocation of patella; in planning of TKA; during the growth of child it allows to assess the progression of deformity.

  2. Angular and axial deformities of the legs of children.

    McDonough, M W


    Age is often a determining factor in establishing a treatment program for these axial and angular problems. As can be seen, the deformities of torsion are noticeable from early life. Any tibial torsion should be treated early, but an excessive medial range of motion in the infant leg with a corresponding adequate lateral range of motion of the limb may be cautiously observed. Medial femoral torsion is a normal early finding in the infant thigh. The problem becomes evident as the child matures without the corresponding reduction in femoral torsion, leading to a persistence of fetal or infantile alignment. The gait consequences are usually noticed at 4 to 8 years of age. The angular changes generally are a delayed finding noticed in stance. The bowleg may be associated with marked tibial torsion and picked up early but the Blount's patient has been traditionally definable at 2 years of age. Levin and Drennan may hasten the time of diagnosis with their radiographic criteria. Knock-knee is an alignment disturbance noticed during the early to mid-childhood years, age 4 to 8 years. The diagnosis is important, differentiating physiologic from torsion-related deformities, and treatment, if warranted, should not be delayed. Generally the earlier these problems are discovered, the more optimistic the prognosis. Since the pediatric limb is in a constant state of transition, there will be a perpetual argument as to the need or efficacy of various approaches to the problems of knock-knee and bowleg. If observation is the treatment of choice, the percentage of cases which go on to osteotomies and epiphyseal stapling will continue. For those with axial or angular deformities, degenerative arthritis of the knee may be forthcoming. Swanson, Greene, and Allis warned of problems becoming "unphysiologic." If we consider the epiphyseal malleability, not only to deformity but to correction, we can appreciate Lenoir's comment of "every day the problem goes untreated is a golden

  3. Chaotic motion in axially symmetric potentials with oblate quadrupole deformation

    Letelier, Patricio S. [Departamento de Matematica Aplicada, IMECC, Universidade Estadual de Campinas, 13083-859, Campinas, SP (Brazil); Ramos-Caro, Javier, E-mail: [Departamento de Matematica Aplicada, IMECC, Universidade Estadual de Campinas, 13083-859, Campinas, SP (Brazil); Lopez-Suspes, Framsol, E-mail: [Facultad de Telecomunicaciones, Universidad Santo Tomas and Escuela de Fisica, Universidad Industrial de Santander, Bucaramanga (Colombia)


    By computing the Poincare's surfaces of section and Lyapunov exponents, we study the effect of introducing an oblate quadrupole in the dynamics associated with two generic spherical potentials of physical interest: the central monopole and the isotropic harmonic oscillator. In the former case we find saddle points in the effective potential, in contrast to the statements presented by Gueron and Letelier in [E. Gueron, P.S. Letelier, Phys. Rev. E 63 (2001) 035201]. The results we show in the second case have application in nuclear or atomic physics. In particular, we find values of oblate deformation leading to a disappearance of shell structure in the single-particle spectrum. -- Highlights: → We find chaotic motion around a monopole with oblate quadrupole deformation. → This corrects the statements introduced in [E. Gueron, P.S. Letelier, Phys. Rev. E 63 (2001) 035201]. → We present an alternative model for the potential due to an oblate deformed nuclei. → This leads to stochastic regions in the phase space of classical orbits. → It suggests that the shell structure of single-particle spectrum tends to disappear.

  4. Axial dependence of optical weak measurements in the critical region

    Araujo, Manoel P; Maia, Gabriel G


    The interference between optical beams of different polarizations plays a fundamental role in reproducing the optical analog of the electron spin weak measurement. The extraordinary point in optical weak measurements is represented by the possibility to estimate with great accuracy the Goos-Haenchen (GH) shift by measuring the distance between the peak of the outgoing beams for two opposite rotation angles of the polarizers located before and after the dielectric block. Starting from the numerical calculation of the GH shift, which clearly shows a frequency crossover for incidence near to the critical angle, we present a detailed study of the interference between s and p polarized waves in the critical region. This allows to determine in which conditions it is possible to avoid axial deformations and reproduce the GH curves. In view of a possible experimental implementation, we give the expected weak measurement curves for Gaussian lasers of different beam waist sizes propagating through borosilicate (BK7) an...

  5. Deformation and failure mechanisms of 18650 battery cells under axial compression

    Zhu, Juner; Zhang, Xiaowei; Sahraei, Elham; Wierzbicki, Tomasz


    An important deformation mode during ground impacts of battery packs made of cylindrical battery cells is axial compression. This type of loading subjects the cell to a complex deformation pattern and failure mechanism. The design of endcaps plays an important role in such deformations. To explore the sequence of deformation and the underlying failure mechanisms, a combined experimental/numerical study was carried out. Tests were conducted on 18650 cells, and the deformation of each component was carefully investigated and documented. There are four different stages in the force-displacement curve, corresponding with deformation of various components in the endcap assembly. A short circuit happens at a displacement of 4 mm. To clarify these observations, a detailed Finite Element model was set up, covering the geometry and the mechanical property of almost all the components of the cell. Using the simulation results, the sequence of the axial compression was revealed, which was subsequently validated by Micro CT scans as well as analytical solutions. Based on the precise analysis of the mechanical behavior, the cause of the short circuit during axial loading was clarified. Two failure mechanisms in the separator at the top section of the cell explain the possible causes of short circuit.

  6. Symmetries and Supersymmetries of the Dirac Hamiltonian with Axially-Deformed Scalar and Vector Potentials

    Leviatan, A


    We consider several classes of symmetries of the Dirac Hamiltonian in 3+1 dimensions, with axially-deformed scalar and vector potentials. The symmetries include the known pseudospin and spin limits and additional symmetries which occur when the potentials depend on different variables. Supersymmetries are observed within each class and the corresponding charges are identified.

  7. Symmetries and supersymmetries of the dirac hamiltonian with axially deformed scalar and vector potentials.

    Leviatan, A


    We consider several classes of symmetries of the Dirac Hamiltonian in 3 + 1 dimensions, with axially deformed scalar and vector potentials. The symmetries include the known pseudospin and spin limits and additional symmetries which occur when the potentials depend on different variables. Supersymmetries are observed within each class and the corresponding charges are identified.

  8. Analyses of axial, lateral and circumferential deformations of rock specimen in triaxial compression

    WANG Xue-bin


    The axial, lateral and circumferential strains were analyzed for a rock specimen subjected to shear failure in the form of a shear band bisecting the specimen in triaxial compression. Plastic deformation of the specimen stemmed from shear strain localization initiated at the peak shear stress. Beyond the onset of strain localization, the axial, lateral and circumferential strains were decomposed into two parts, respectively. One is the elas-tic strain described by general Hooke's law. The other is attributable to the plastic shear slips along shear band with a certain thickness dependent on the internal length of rock.The post-peak circumferential strain-axial strain curve of longer specimen is steeper than that of shorter specimen, as is consistent with the previous experiments. In elastic stage,the circumferential strain-axial strain curve exhibits nonlinear characteristic, as is in agreement with the previous experiment since confining pressure is loaded progressively until a certain value is reached. When the confining pressure is loaded completely, the circumferential strain-axial strain curve is linear in elastic and strain-softening stages. The predicted circumferential strain-axial strain curve in elastic and strain- softening stages agrees with the previous experiment.

  9. Inflation-predictable behavior and co-eruption deformation at Axial Seamount

    Nooner, Scott L.; Chadwick, William W.


    Deformation of the ground surface at active volcanoes provides information about magma movements at depth. Improved seafloor deformation measurements between 2011 and 2015 documented a fourfold increase in magma supply and confirmed that Axial Seamount’s eruptive behavior is inflation-predictable, probably triggered by a critical level of magmatic pressure. A 2015 eruption was successfully forecast on the basis of this deformation pattern and marked the first time that deflation and tilt were captured in real time by a new seafloor cabled observatory, revealing the timing, location, and volume of eruption-related magma movements. Improved modeling of the deformation suggests a steeply dipping prolate-spheroid pressure source beneath the eastern caldera that is consistent with the location of the zone of highest melt within the subcaldera magma reservoir determined from multichannel seismic results.

  10. Regional brain axial and radial diffusivity changes during development.

    Kumar, Rajesh; Nguyen, Haidang D; Macey, Paul M; Woo, Mary A; Harper, Ronald M


    The developing human brain shows rapid myelination and axonal changes during childhood, adolescence, and early adulthood, requiring successive evaluations to determine normative values for potential pathological assessment. Fiber characteristics can be examined by axial and radial diffusivity procedures, which measure water diffusion parallel and perpendicular to axons and show primarily axonal status and myelin changes, respectively. Such measures are lacking from widespread sites for the developing brain. Diffusion tensor imaging data were acquired from 30 healthy subjects (age 17.7 ± 4.6 years, range 8-24 years, body mass index 21.5 ± 4.5 kg/m(2), 18 males) using a 3.0-Tesla MRI scanner. Diffusion tensors were calculated, principal eigenvalues determined, and axial and radial diffusivity maps calculated and normalized to a common space. A set of regions of interest was outlined from widespread brain areas within rostral, thalamic, hypothalamic, cerebellar, and pontine regions, and average diffusivity values were calculated using normalized diffusivity maps and these regions of interest masks. Age-related changes were assessed with Pearson's correlations, and gender differences evaluated with Student's t-tests. Axial and radial diffusivity values declined with age in the majority of brain areas, except for midhippocampus, where axial diffusivity values correlated positively with age. Gender differences emerged within putamen, thalamic, hypothalamic, cerebellar, limbic, temporal, and other cortical sites. Documentation of normal axial and radial diffusivity values will help assess disease-related tissue changes. Axial and radial diffusivities change with age,with fiber structure and organization differing between sexes in several brain areas. The findings may underlie gender-based functional characteristics, and mandate partitioning age- and gender-related changes during developmental brain pathology evaluation.

  11. Innovative design of composite structures: Axisymmetric deformations of unsymmetrically laminated cylinders loaded in axial compression

    Hyer, M. W.; Paraska, P. J.


    The study focuses on the axisymmetric deformation response of unsymmetrically laminate cylinders loaded in axial compression by known loads. A geometrically nonlinear analysis is used. Though buckling is not studied, the deformations can be considered to be the prebuckling response. Attention is directed at three 16 layer laminates: a (90 sub 8/0 sub 8) sub T; a (0 sub 8/90 sub 8) sub T and a (0/90) sub 4s. The symmetric laminate is used as a basis for comparison, while the two unsymmetric laminates were chosen because they have equal but opposite bending-stretching effects. Particular attention is given to the influence of the thermally-induced preloading deformations that accompany the cool-down of any unsymmetric laminate from the consolidation temperature. Simple support and clamped boundary conditions are considered. It is concluded that: (1) The radial deformations of an unsymmetric laminate are significantly larger than the radial deformations of a symmetric laminate, although for both symmetric and unsymmetric laminates the large deformations are confined to a boundary layer near the ends of the cylinder; (2) For this nonlinear problem the length of the boundary layer is a function of the applied load; (3) The sign of the radial deformations near the supported end of the cylinder depends strongly on the sense (sign) of the laminate asymmetry; (4) For unsymmetric laminates, ignoring the thermally-induced preloading deformations that accompany cool-down results in load-induced deformations that are under predicted; and (5) The support conditions strongly influence the response but the influence of the sense of asymmetry and the influence of the thermally-induced preloading deformations are independent of the support conditions.

  12. Nonlocal shear deformable shell model for postbuckling of axially compressed microtubules embedded in an elastic medium.

    Shen, Hui-Shen


    Buckling and postbuckling analysis is presented for axially compressed microtubules (MTs) embedded in an elastic matrix of cytoplasm. The microtubule is modeled as a nonlocal shear deformable cylindrical shell which contains small scale effects. The surrounding elastic medium is modeled as a Pasternak foundation. The governing equations are based on higher order shear deformation shell theory with a von Kármán-Donnell-type of kinematic nonlinearity and include the extension-twist and flexural-twist couplings. The thermal effects are also included and the material properties are assumed to be temperature-dependent. The small scale parameter e (0) a is estimated by matching the buckling load from their vibrational behavior of MTs with the numerical results obtained from the nonlocal shear deformable shell model. The numerical results show that buckling load and postbuckling behavior of MTs are very sensitive to the small scale parameter e (0) a. The results reveal that the MTs under axial compressive loading condition have an unstable postbuckling path, and the lateral constraint has a significant effect on the postbuckling response of a microtubule when the foundation stiffness is sufficiently large.

  13. Strength and Deformation of Axially Loaded Fiber-Reinforced Polymer Sheet Confined Concrete Columns

    李静; 钱稼茹; 蒋剑彪


    Experimental results of 29 axially loaded fiber-reinforced polymer sheet (FS) confined concrete columns and two reference plain concrete columns are introduced. Twenty four column specimens were confined with carbon fiber sheet (CFS) and five column specimens were hybrid confined with both CFS and glass fiber sheet (GFS). The influence of aspect ratio, FS material, initial axial force ratio, and FS confinement degree on the strength and deformation of columns were studied. Based on the experimental results, the equations of complete stress-strain curve of CFS confined concrete are proposed. These equations are suitable for the nonlinear analysis of square and rectangular section columns. Suggestions of applying FS to confine concrete columns are presented.

  14. Finite Amplitude Method for Charge-Changing Transitions in Axially-Deformed Nuclei

    Mustonen, M T; Zenginerler, Z; Engel, J


    We describe and apply a version of the finite amplitude method for obtaining the charge-changing nuclear response in the quasiparticle random phase approximation. The method is suitable for calculating strength functions and beta-decay rates, both allowed and forbidden, in axially-deformed open-shell nuclei. We demonstrate the speed and versatility of the code through a preliminary examination of the effects of tensor terms in Skyrme functionals on beta decay in a set of spherical and deformed open-shell nuclei. Like the isoscalar pairing interaction, the tensor terms systematically increase allowed beta-decay rates. This finding generalizes previous work in semimagic nuclei and points to the need for a comprehensive study of time-odd terms in nuclear density functionals.

  15. Effect of Deformation Condition on Axial CompressivePrecision Forming Process of Tube with Curling Die


    The effect of the deformation condition on the axial compressive precision forming process of tube with curling die was investigated by using a rigid-plastic FEM. The results show that the forming accuracy depends mainly on geometric condition rρ/d0, little on tube material properties and friction condition; the relative gap Δ/2rρ of double-walled tubes obtained decreases with increasing rρ/d0, and there is a parameter k for a given t0/d0 or rρ/t0, when rρ,/d0>k, Δ/2rρ<1,otherwise Δ/2rρ>1.

  16. Octupole Deformed Nuclei in the Actinide Region

    Thorsteinsen, T; Rubio barroso, B; Simpson, J; Gulda, K; Sanchez-vega, M; Cocks, J; Nybo, K; Garcia borge, M; Aas, A; Fogelberg, B; Honsi, J; Smith, G; Naumann, R; Grant, I


    The aim of the present study is to investigate the limits of the "island" of octupole deformation in the mass region A=225. It is of particular importance to demonstrate experimentally the sudden disappearance of the stable octupole deformation in the presence of a well developed quadrupole field. \\\\ \\\\In order to establish the upper border line the $\\beta$ -decay chains of $^{227}$Rn $\\rightarrow ^{227}$Fr $\\rightarrow ^{227}$Ra and $^{231}$Fr $\\rightarrow ^{231}$Ra $\\rightarrow ^{231}$Ac were studied at PSB-ISOLDE using advanced fast timing and $\\gamma$-ray spectroscopy techniques. The lifetimes of the excited states have been measured in the picosecond range using the time-delayed $\\beta\\gamma\\gamma$(t) method.

  17. Influence of angular momentum in axially symmetric potentials with octupole deformation

    JIN Hua; SUN Zhen-Wu; ZHENG Ren-Rong


    The chaotic classical single-particle motion in an oblate octupole deformed potential with a non-zero z-component of angular momentum Lz is investigated. The stability analysis of the trajectories shows that with increasing rotation of the system, the unstable negative curvature regions of the effective potential surface decrease, which converts the chaotic motion of the system into a regular one.

  18. Description of the ground state of axially deformed nuclei within the Relativistic Hartree-Fock-Bogoliubov model

    Ebran, J-P [CEA/DAM/DIF, F-91297 Arpajon (France); Khan, E; Arteaga, D Pena [Institut de Physique Nucleaire, University Paris-Sud, IN2P3-CNRS, F-91406 Orsay Cedex (France); Vretenar, D, E-mail: [Physics Department, Faculty of Science, University of Zagreb, 10000 Zagreb (Croatia)


    The Relativistic Hartree-Fock-Bogoliubov model for axially deformed nuclei (RHFBz) is presented. The model involves a phenomenological Lagrangian with density-dependent meson-nucleon couplings in the particle-hole channel and the central part of the Gogny force in the particle-particle channel. The RHFBz equations are solved by expansion in the basis of a deformed harmonic oscillator. Illustrative RHFBz calculations are performed for Neon isotopes.

  19. Multi-axial load application and DIC measurement of advanced composite beam deformation behavior

    Berggreen C.


    Full Text Available For the validation of a new beam element formulation, a wide set of experimental data consisting of deformation patterns obtained for a number of specially designed composite beam elements, have been obtained. The composite materials applied in the beams consist of glass-fiber reinforced plastic with specially designed layup configurations promoting advanced coupling behavior. Furthermore, the beams are designed with different cross-section shapes. The data obtained from the experiments are also used in order to improve the general understanding related to practical implementation of mechanisms of elastic couplings due to anisotropic properties of composite materials. The knowledge gained from these experiments is therefore essential in order to facilitate an implementation of passive control in future large wind turbine blades. A test setup based on a four-column MTS servo-hydraulic testing machine with a maximum capacity of 100 kN was developed, see Figure 1. The setup allows installing and testing beams of different cross-sections applying load cases such as axial extension, shear force bending, pure bending in two principal directions as well as pure torsion, see Figure 2. In order to apply multi-axial loading, a load application system consisting of three hydraulic actuators were mounted in two planes using multi-axial servo-hydraulic control. The actuator setup consists of the main actuator on the servo-hydraulic test machine working in the vertical axis (depicted on Figure 1 placed at the testing machine crosshead and used for application of vertical forces to the specimens. Two extra actuators are placed in a horizontal plane on the T-slot table of the test machine in different positions in order to apply loading at the tip of the specimen in various configurations. In order to precisely characterize the global as well as surface deformations of the beam specimens tested, a combination of different measurement systems were used during

  20. Fully automatic measurements of axial vertebral rotation for assessment of spinal deformity in idiopathic scoliosis

    Forsberg, Daniel; Lundström, Claes; Andersson, Mats; Vavruch, Ludvig; Tropp, Hans; Knutsson, Hans


    Reliable measurements of spinal deformities in idiopathic scoliosis are vital, since they are used for assessing the degree of scoliosis, deciding upon treatment and monitoring the progression of the disease. However, commonly used two dimensional methods (e.g. the Cobb angle) do not fully capture the three dimensional deformity at hand in scoliosis, of which axial vertebral rotation (AVR) is considered to be of great importance. There are manual methods for measuring the AVR, but they are often time-consuming and related with a high intra- and inter-observer variability. In this paper, we present a fully automatic method for estimating the AVR in images from computed tomography. The proposed method is evaluated on four scoliotic patients with 17 vertebrae each and compared with manual measurements performed by three observers using the standard method by Aaro-Dahlborn. The comparison shows that the difference in measured AVR between automatic and manual measurements are on the same level as the inter-observer difference. This is further supported by a high intraclass correlation coefficient (0.971-0.979), obtained when comparing the automatic measurements with the manual measurements of each observer. Hence, the provided results and the computational performance, only requiring approximately 10 to 15 s for processing an entire volume, demonstrate the potential clinical value of the proposed method.

  1. Deformation Behavior and TExture Evolution of Steel Alloys under Axial-Torsional Loading

    Siriruk, A.; Kant, M.; Penumadu, D.; Garlea, E.; Vogel, S.


    Using hollow cylinder samples with suitable geometry obtained from round bar stock, the deformation behavior of bcc Fe based 12L14 steel alloy is evaluated under multi-axial conditions. A stacked strain gage rosette and extensometer mounted on the cylindrical surface at the mid height of the specimen provided strain tensor as a function of applied stress for pure tensile and torsion tests prior to yielding. This study examines elastic and yield behavior and effects of these with respect to texture evolution. Hollow cylinder specimen geometry (tubes) with small wall thickness and relatively (to its thickness) large inner diameter is used. The variation of observed yield surface in deviatoric plane and the effect on mode of deformation (tension versus torsion versus its combination) on stress-strain behavior is discussed. Bulk texture was studied using neutron time-of-flight diffractometer at High-Pressure-Preferred Orientation (HIPPO) - Los Alamos Neutron Science Center (LANSCE) instrument and the evolution of texture and related anisotropy for pure tension versus torsion are also included.

  2. Theoretical study on effect of radial and axial deformation on electron transport properties in a semiconducting Si–C nanotube

    Sudhanshu Choudhary; S Qureshi


    We investigate electron transport properties in a deformed (8, 0) silicon carbide nanotube by applying self consistent non-equilibrium Green’s function formalism in combination with the density-functional theory to a two-probe molecular junction constructed from deformed nanotube. The results suggest significant reduction in threshold voltage in the case of both radially compressed and axially elongated (8, 0) SiCNTs, a large difference in current–voltage characteristics was observed. Analysis of frontier molecular orbitals (FMO) and transmission spectrum show bandgap reduction in deformed nanotubes. Deformation introduces electronic states near the Fermi level, enhancing the conduction properties of (8, 0) SiCNT. The FMOs and the orbitals corresponding to peaks in () around Fermi level obviously has some major contributions from the deformed site. However, localization of the electronic state near the Fermi level is weak in (8, 0) SiCNT, possibly because of its large bandgap.

  3. Fluid–structure coupling analysis of deformation and stress in impeller of an axial-flow pump with two-way passage

    Ji Pei


    Full Text Available Axial-flow pump with a two-way passage has been widely employed in irrigation and drainage projects. Because of the shape of the two-way inlet passage, the impeller easily induces vibration due to unstable turbulent flow. This vibration results in structural cracks and even hinders the safe operation of the pump. Deformation and stress distributions in the impeller were calculated using two-way coupled fluid–structure interaction simulations, and a quantitative analysis of blade deformation and stress is carried out to determine the structure critical region. The results show that the values of deformation and stress significantly decrease with an increasing flow rate and a decreasing head, and the maximum total deformation can be found in the impeller rim, while the maximum equivalent stress can be obtained near the impeller hub. The total deformations in the blade rim decrease from blade leading edge to trailing edge, and the equivalent stress in the blade hub initially increases and then declines, and in the end, it rapidly increases from the blade outlet to inlet. These results reveal the deformation and stress in the impeller to ensure reliability and specific theoretical guidance for the structural optimization design of a pump device.

  4. C sub 6 sub 0 fullerene and its molecular complexes under axial and shear deformation

    Spitsina, N G; Bashkin, I V; Meletov, K P


    We have studied the pristine C sub 6 sub 0 and its molecular complexes with the organic donors bis(ethylenedithio) tetrathiafulvalene (BEDT-TTF or ET) and tetramethyltetraselenafulvalene (TMTSF) by means of ESR and Raman spectroscopy at high pressure. The important changes in the ESR signal of C sub 6 sub 0 were observed under axial pressure combined with shear deformation. It is shown that the treatment at a anisotropic pressure of 4 GPa results in a reduction in the symmetry of the C sub 6 sub 0 molecule and the formation of radicals. Treatment of the molecular complex of (ET) sub 2 centre dot C sub 6 sub 0 at a pressure of approx 4.5 GPa and a temperature of 150 deg. C leads to the formation of C sub 6 sub 0 dimers. The Raman spectra of the molecular complex C sub 6 sub 0 centre dot TMTSF centre dot 2(CS sub 2) were measured in situ at ambient temperature and pressures up to 9.5 GPa. The pressure behaviour of the Raman peaks reveals singularity at 5.0 +- 0.5 GPa related to the softening and splitting of so...

  5. Regional manifold learning for deformable registration of brain MR images.

    Ye, Dong Hye; Hamm, Jihun; Kwon, Dongjin; Davatzikos, Christos; Pohl, Kilian M


    We propose a method for deformable registration based on learning the manifolds of individual brain regions. Recent publications on registration of medical images advocate the use of manifold learning in order to confine the search space to anatomically plausible deformations. Existing methods construct manifolds based on a single metric over the entire image domain thus frequently miss regional brain variations. We address this issue by first learning manifolds for specific regions and then computing region-specific deformations from these manifolds. We then determine deformations for the entire image domain by learning the global manifold in such a way that it preserves the region-specific deformations. We evaluate the accuracy of our method by applying it to the LPBA40 dataset and measuring the overlap of the deformed segmentations. The result shows significant improvement in registration accuracy on cortex regions compared to other state of the art methods.

  6. Probing the symmetries of the Dirac Hamiltonian with axially deformed scalar and vector potentials by similarity renormalization group.

    Guo, Jian-You; Chen, Shou-Wan; Niu, Zhong-Ming; Li, Dong-Peng; Liu, Quan


    Symmetry is an important and basic topic in physics. The similarity renormalization group theory provides a novel view to study the symmetries hidden in the Dirac Hamiltonian, especially for the deformed system. Based on the similarity renormalization group theory, the contributions from the nonrelativistic term, the spin-orbit term, the dynamical term, the relativistic modification of kinetic energy, and the Darwin term are self-consistently extracted from a general Dirac Hamiltonian and, hence, we get an accurate description for their dependence on the deformation. Taking an axially deformed nucleus as an example, we find that the self-consistent description of the nonrelativistic term, spin-orbit term, and dynamical term is crucial for understanding the relativistic symmetries and their breaking in a deformed nuclear system.

  7. Effect of Radial and Axial Deformation on Electron Transport Properties in a Semiconducting Si-C Nanotube

    S. Choudhary


    Full Text Available We study the bias voltage dependent current characteristic in a deformed (8, 0 silicon carbide nanotube by applying self consistent non-equilibrium Green’s function formalism in combination with the density-functional theory to a two probe molecular junction constructed from deformed nanotube. The transmission spectra and electron density of states at zero bias shows a significant reduction in threshold in the case of both radially compressed and axially elongated nanotube. However, semiconductor to metal transition was not observed, though the results show large differences in current characteristic compared to a perfect nanotube.

  8. Influence of axial deformation of pipe string on down-hole operation%管柱轴向变形对井下作业的影响



    This paper reviews the impact of axial deformation of string on different down-hole operating conditions along with the importance of the calculation on axial deformation for the establishment of calculation model of down-hole string axial deformation theory.%综合分析了管柱轴向变形对井下不同作业工况的影响,阐述了计算井下作业管柱轴向变形的重要性,为建立井下作业管柱轴向变形理论计算模型做了很好的铺垫。

  9. Correction of the axial and appendicular deformities in a patient with Silver-Russel syndrome

    Ali Al Kaissi


    Full Text Available Background: Scoliosis and limb length discrepancy are the major orthopaedic abnormalities in patients with Silver-Russel syndrome (SRS. In this paper, we describe a series of orthopaedic interventions in an attempt to overcome the progressive pathologic mechanism in a 7-year-old girl who manifested the full phenotypic features of SRS. Materials and Methods: Unilateral hip dislocation, progressive scoliosis and limb length discrepancy have been dealt with through Pemberton osteotomy, spinal fusion and Taylor-Spatial-Frame respectively. Results: In order to correct the axial and the appendicular deformities a sum of seven operations were performed (between the age of 7 years and 13 years. Pemberton osteotomy was performed to treat dislocation of her right hip because of developmental dysplasia of the hip. Spinal fusion (spondylodesis of segments Th3-L5 was done to correct her scoliosis. And, to overcome the limb length discrepancy of 15-cm we used Taylor-Spatial-Frame with percutaneous distal corticotomy of the femur, and the proximal tibia, as well as the foot, were performed. We were able to minimize the limb length discrepancy to 5 cm. The girl became able to walk with the aid of a below knee orthosis and through lifting the left limb with 5-cm height shoe. Conclusion: Limb lengthening surgery in patients with multiple malformation complex as in SRS is associated with high recurrence risk because of; muscular hypotonia, overtubulation of the long bones, and the poor bone regenerative quality. Our interventions were principally directed towards improving the cosmetic outlook, functions and the biomechanics.

  10. Regional ground deformation and its controlling measures in China

    Zhou, Zhifang; Zhu, Haisheng; Huang, Yong


    With the development of construction of China Cities, there exist a lot of environmental geological problems involved in the geofracture, land subsidence, collapse, landslide, devolution, mudrock flow, floating sand, piping and soft ground deformation. Of big cities whose population is over one million in China, about 30 cities appears the land subsidence region. Other cities locate in the regions of collapse yellow earth or expand soil of strong swell-shrink charasteristic, soft ground and karst. In the paper, the cause and hazard of regionality ground deformation is summed up. The causes of regional land deformation caused by the natural geological effect and activities of human being are analyzed. According to the length of deformation course and endanger of society, economy and life, land deformation involves three types, that is, the delay, rapid and break land deformation. And the concrete countermeasure and method are provided.

  11. Comparison between formulas of rotational band for axially symmetric deformed nuclei

    WU Xi; LEI Yi-An


    The experimental rotational spectra of the deformed nuclei available in even-even and odd-A nuclei in the rare-earth and actinide regions are systematically analyzed with several rotational spectra formulas,including Bohr-Mottelson's I(I+l)-expansion,Harris'w2-expansion,ab and abc formulas.It is shown that the simple 2-parameter ab formula is much better than the widely used 2-parameter Bohr-Mottelson's AB formula and Harris'αβ formula.The available data of the rotational spectra of both ground-state band in even-even nuclei and one-quaasiparticle band in odd-A nuclei can be conveniently and rather accurately reproduced by ab formula and abc formula.The moment of inertia and the variation with rotational frequency of angular momentum can be satisfactorily reproduced by ab and abc formulas.

  12. [The deformation behavior of human lumbar intervertebral discs subjected to long term axial dynamic compressive forces (author's transl)].

    Köller, W; Funke, F; Hartmann, F


    49 specimens were studied in 67 axial compression tests; the duration test varied between 2 and 6 hours. All discs showed marked creep; after a big decrease in the first minutes the rate of creep decreases still slightly. Additional the results reveal a decreasing axial deformability with time. In the beginning of a test quickly the viscoelastic behavior alters to such a steady state that the disc behaves more like an elastic body. Loss of mass normally observed after compression tests is due to loss of liquid, but liquid absorption during mechanical load is possible too. The long term biochmechanical behavior is reproducible very well; a second experiment done with the same disc yields nearly the same results.

  13. Deformed suq(2) with deformed Coriolis effect description of superdeformed nuclei in A ~ 190 region

    Alharbi, Hamoud; Alhendi, Hamad; Aloyayd, Turki


    The deformed suq(2) model with Coriolis effect is applied to 79 superdeformed bands in the region A ~ 190. The transition energies and the moments of inertia are calculated within the model and their validity is investigated by comparing them with the experimental data. The effect of deformation of Coriolis effect in the transition energies and the moments of inertia was investigated. A comparison between the suq(2) with and without deformed Coriolis effect is made and shows significant improvements in fitting the experimental data. It was shown that deformation of improve the standard deviation of the transition energies up to 80%. Correlation between the deformation parameter ? and the excesses of neutrons over protons, S, has been observed. This correlation shows a decaying behavior. As a result, the deformation of Coriolis effect becomes weak with the increase of S.

  14. Nuclear deformations in the A approx. = 80-100 region

    Galeriu, D.; Bucurescu, D.; Ivascu, M.


    The occurrence of highly deformed nuclei in the A approx.80 and A approx.= 100 mass regions has been investigated in the framework of the Strutinsky approach with a Nilsson-type potential and the Yukawa-plus-exponential macroscopy mass formula, including elongation, necking and ..gamma.. deformation. Special emphasis was given to the spin-orbit potential parameters, which have large variations at the magic numbers and also depend on the shell filling. Good reproduction of the masses, deformations and shape transition was achieved in both mass regions. The phenomena of shape coexistence are also supported by the calculated potential energy surfaces. The odd-particle influence in driving the nucleus to deformed shapes is demonstrated. The results obtained are rather similar to those of the more elaborated Yukawa shell-model calculations, and show for the first time that a Nilsson-type model can also account for the large deformations of the light Kr, Sr and Zr nuclei.

  15. Concrete-Filled-Large Deformable FRP Tubular Columns under Axial Compressive Loading

    Omar I. Abdelkarim; Mohamed A. ElGawady


    The behavior of concrete-filled fiber tubes (CFFT) polymers under axial compressive loading was investigated. Unlike the traditional fiber reinforced polymers (FRP) such as carbon, glass, aramid, etc., the FRP tubes in this study were designed using large rupture strains FRP which are made of recycled materials such as plastic bottles; hence, large rupture strain (LRS) FRP composites are environmentally friendly and can be used in the context of green construction. This study performed finite...

  16. Concrete-Filled-Large Deformable FRP Tubular Columns under Axial Compressive Loading

    Omar I. Abdelkarim


    Full Text Available The behavior of concrete-filled fiber tubes (CFFT polymers under axial compressive loading was investigated. Unlike the traditional fiber reinforced polymers (FRP such as carbon, glass, aramid, etc., the FRP tubes in this study were designed using large rupture strains FRP which are made of recycled materials such as plastic bottles; hence, large rupture strain (LRS FRP composites are environmentally friendly and can be used in the context of green construction. This study performed finite element (FE analysis using LS-DYNA software to conduct an extensive parametric study on CFFT. The effects of the FRP confinement ratio, the unconfined concrete compressive strength ( , column size, and column aspect ratio on the behavior of the CFFT under axial compressive loading were investigated during this study. A comparison between the behavior of the CFFTs with LRS-FRP and those with traditional FRP (carbon and glass with a high range of confinement ratios was conducted as well. A new hybrid FRP system combined with traditional and LRS-FRP is proposed. Generally, the CFFTs with LRS-FRP showed remarkable behavior under axial loading in strength and ultimate strain. Equations to estimate the concrete dilation parameter and dilation angle of the CFFTs with LRS-FRP tubes and hybrid FRP tubes are suggested.

  17. Axial Region Optimization for Cycle Length Extension of Small Modular PWR

    Choe, Ji Won [UNIST, Ulsan (Korea, Republic of); Shin, Ho Cheol; Jung, Ji Eun [KHNP CRI, Daejeon (Korea, Republic of); Zheng, Youqi; Tak, Tae Woo; Lee, Deok Jung [UNIST, Ulsan (Korea, Republic of)


    This paper studied axial region sensitivity test in SMPWR to extend the cycle length. Zr- {sup 167}Er, Zr-B and Zr-Gd are used for BA material, the height of cutback and axial region has been changed. The cycle length of the reference core is 798 EFPD (26.6 EFPM), and there is no cutback and only {sup 167}Er-Zr is used in R-BA.Soluble boron-free small modular pressurized water reactor (SMPWR) can be a transportable size core due to the absence of the chemical volume control system (CVCS) and the amount of liquid radioactive waste, and further remove the corrosion problem caused by boric acid. The SMPWR needs large amount of burnable absorber (BA) instead of soluble boron, but the more the amount of BA is, the shorter the fuel cycle length is. Therefore, this paper studies axial region sensitivity test to make fuel cycle length of SMWPR longer. The procedure of axial region sensitivity test is as follows: cutback sensitivity tests, material and height sensitivity tests in the axial's reactor core design code system, has been used for these simulation. The optimal BA for cutback region is 10 cm of cutback with natural Gd 10 % in Zr-Gd, and the cycle length increases to 942 EFPD (31.4 months). Through the axial region sensitivity test, the cycle length becomes 1026 EFPD (34.2 months), but the peaking factors were not satisfied their limits. The 4.8-month increases compared with the reference core through the cutback sensitivity test. The possibility to excess reactivity with control rods in this core should verify.

  18. Fayans functional for deformed nuclei. Uranium region

    Tolokonnikov, S V; Kortelainen, M; Lutostansky, Yu S; Saperstein, E E


    Fayans energy density functional (EDF) FaNDF^0 has been applied to the nuclei around uranium region. Ground state characteristics of the Th, U and Pu isotopic chains, up to the two-neutron drip line, are found and compared with predictions from several Skyrme EDFs. The two-neutron drip line is found for FaNDF^0, SLy4 and SkM^* EDFs for a set of elements with even proton number, from Pb up to Fm.

  19. Timing and Style of Deformation in the Floresta Massif, Axial Eastern Cordillera, Colombia

    Saylor, J.; Stockli, D. F.; Mora, A.


    The Floresta Massif is one of the largest exposures of Paleozoic and Pre-Cambrian rocks in the Eastern Cordillera. Estimates for the age of onset of shortening-related deformation in the Eastern Cordillera range from late Cretaceous to late Miocene (e.g., Hoorn et al., 1995; Bayona et al., 2008; Parra et al., 2009). The massif is typically interpreted as being exhumed along a high-angle reverse fault (the Soapaga fault) that reactivated Mesozoic extensional structures (e.g., Kammer and Sanchez, 2006). We examined these dual linked issued with new zircon U/Th-He (ZHe) data, new geological mapping and previously published apatite fission track (AFT) data from the Floresta Massif and the associated footwall strata. Previously, an overturned Paleozoic - Cretaceous sequence was mapped emplaced on Tertiary strata along the Soapaga fault. However, new geologic mapping identifies two previously unrecognized thrusts which place, from west to east, Paleozoic strata on Jurassic strata (Fault 3), Jurassic strata on Cretaceous strata (Fault 2) and Cretaceous strata on Tertiary strata (along the previously identified Fault 1). These results are confirmed by AFT and ZHe data. ZHe ages show no resetting in the Tertiary footwall strata, but show partial resetting in the Cretaceous strata and full resetting in the Jurassic and Paleozoic strata. Similarly, AFT data show older ages in the Cretaceous strata than in the Jurassic or Paleozoic strata. Fully reset ZHe ages from Jurassic strata show that exhumation of the Floresta Massif was ongoing by at least the early Oligocene (~ 30 Ma). However, this deformation post-dates an older episode of deformation associated with partially reset ZHe ages in the Cretaceous strata. Based on a decrease in lag time in detrital ZHe data, we infer that the earlier episode of deformation occurred in the mid - late Eocene (45 - 35 Ma).

  20. Nuclear Phase Transition from Spherical to Axially Symmetric Deformed Shapes Using Interacting Boson Model

    Khalaf A. M.


    Full Text Available The interacting boson model (sd-IBM1 with intrinsic coherent state is used to study the shape phase transitions from spherical U(5 to prolate deformed SU(3 shapes in Nd- Sm isotopic chains. The Hamiltonian is written in the creation and annihilation form with one and two body terms.For each nucleus a fitting procedure is adopted to get the best model parameters by fitting selected experimental energy levels, B(E2 transi- tion rates and two-neutron separation energies with the calculated ones.The U(5-SU(3 IBM potential energy surfaces (PES’s are analyzed and the critical phase transition points are identified in the space of model parameters.In Nd-Sm isotopic chains nuclei evolve from spherical to deformed shapes by increasing the boson number. The nuclei 150 Nd and 152 Sm have been found to be close to critical points.We have also studied the energy ratios and the B(E2 values for yrast band at the critical points.

  1. Fascial deformation in the lateral elbow region: A conceptual approach

    R. Stoeckart (Rob); A. Vleeming (Andry); J.L. Simons; R.P. van Helvoirt (R.); C.J. Snijders (Chris)


    markdownabstractAbstract In embalmed preparations, the antebrachial fascia in the lateral elbow region is shown to be deformed by load application to the triceps muscle. From this fascia, muscles arise which are primarily concerned with the extension of wrist and fingers. In the case of lateral ep

  2. Fascial deformation in the lateral elbow region: A conceptual approach

    R. Stoeckart (Rob); A. Vleeming (Andry); J.L. Simons; R.P. van Helvoirt (R.); C.J. Snijders (Chris)


    markdownabstractAbstract In embalmed preparations, the antebrachial fascia in the lateral elbow region is shown to be deformed by load application to the triceps muscle. From this fascia, muscles arise which are primarily concerned with the extension of wrist and fingers. In the case of lateral ep

  3. Fascial deformation in the lateral elbow region: A conceptual approach

    R. Stoeckart (Rob); A. Vleeming (Andry); J.L. Simons; R.P. van Helvoirt (R.); C.J. Snijders (Chris)


    markdownabstractAbstract In embalmed preparations, the antebrachial fascia in the lateral elbow region is shown to be deformed by load application to the triceps muscle. From this fascia, muscles arise which are primarily concerned with the extension of wrist and fingers. In the case of lateral

  4. Deformations of Axially Symmetric Initial Data and the Mass-Angular Momentum Inequality

    Cha, Ye Sle


    We show how to reduce the general formulation of the mass-angular momentum inequality, for axisymmetric initial data of the Einstein equations, to the known maximal case whenever a geometrically motivated system of equations admits a solution. This procedure is based on a certain deformation of the initial data which preserves the relevant geometry, while achieving the maximal condition and its implied inequality (in a weak sense) for the scalar curvature; this answers a question posed by R. Schoen. The primary equation involved, bears a strong resemblance to the Jang-type equations studied in the context of the positive mass theorem and the Penrose inequality. Each equation in the system is analyzed in detail individually, and it is shown that appropriate existence/uniqueness results hold with the solution satisfying desired asymptotics. Lastly, it is shown that the same reduction argument applies to the basic inequality yielding a lower bound for the area of black holes in terms of mass and angular momentum...

  5. Implications of the center of rotation concept for the reconstruction of anterior column lordosis and axial preloads in spinal deformity surgery.

    Koller, Heiko; Mayer, Michael; Zenner, Juliane; Resch, Herbert; Niederberger, Alfred; Fierlbeck, Johann; Hitzl, Wolfgang; Acosta, Frank L


    In thoracolumbar deformity surgery, anterior-only approaches are used for reconstruction of anterior column failures. It is generally advised that vertebral body replacements (VBRs) should be preloaded by compression. However, little is known regarding the impact of different techniques for generation of preloads and which surgical principle is best for restoration of lordosis. Therefore, the authors analyzed the effect of different surgical techniques to restore spinal alignment and lordosis as well as the ability to generate axial preloads on VBRs in anterior column reconstructions. The authors performed a laboratory study using 7 fresh-frozen specimens (from T-3 to S-1) to assess the ability for lordosis reconstruction of 5 techniques and their potential for increasing preloads on a modified distractable VBR in a 1-level thoracolumbar corpectomy. The testing protocol was as follows: 1) Radiographs of specimens were obtained. 2) A 1-level corpectomy was performed. 3) In alternating order, lordosis was applied using 1 of the 5 techniques. Then, preloads during insertion and after relaxation using the modified distractable VBR were assessed using a miniature load-cell incorporated in the modified distractable VBR. The modified distractable VBR was inserted into the corpectomy defect after lordosis was applied using 1) a lamina spreader; 2) the modified distractable VBR only; 3) the ArcoFix System (an angular stable plate system enabling in situ reduction); 4) a lordosizer (a customized instrument enabling reduction while replicating the intervertebral center of rotation [COR] according to the COR method); and 5) a lordosizer and top-loading screws ([LZ+TLS], distraction with the lordosizer applied on a 5.5-mm rod linked to 2 top-loading pedicle screws inserted laterally into the vertebra). Changes in the regional kyphosis angle were assessed radiographically using the Cobb method. The bone mineral density of specimens was 0.72 ± 22.6 g/cm(2). The maximum regional

  6. Temporal evolution of continental lithospheric strength in actively deforming regions

    Thatcher, W.; Pollitz, F.F.


    It has been agreed for nearly a century that a strong, load-bearing outer layer of earth is required to support mountain ranges, transmit stresses to deform active regions and store elastic strain to generate earthquakes. However the dept and extent of this strong layer remain controversial. Here we use a variety of observations to infer the distribution of lithospheric strength in the active western United States from seismic to steady-state time scales. We use evidence from post-seismic transient and earthquake cycle deformation reservoir loading glacio-isostatic adjustment, and lithosphere isostatic adjustment to large surface and subsurface loads. The nearly perfectly elastic behavior of Earth's crust and mantle at the time scale of seismic wave propagation evolves to that of a strong, elastic crust and weak, ductile upper mantle lithosphere at both earthquake cycle (EC, ???10?? to 103 yr) and glacio-isostatic adjustment (GIA, ???103 to 104 yr) time scales. Topography and gravity field correlations indicate that lithosphere isostatic adjustment (LIA) on ???106-107 yr time scales occurs with most lithospheric stress supported by an upper crust overlying a much weaker ductile subtrate. These comparisons suggest that the upper mantle lithosphere is weaker than the crust at all time scales longer than seismic. In contrast, the lower crust has a chameleon-like behavior, strong at EC and GIA time scales and weak for LIA and steady-state deformation processes. The lower crust might even take on a third identity in regions of rapid crustal extension or continental collision, where anomalously high temperatures may lead to large-scale ductile flow in a lower crustal layer that is locally weaker than the upper mantle. Modeling of lithospheric processes in active regions thus cannot use a one-size-fits-all prescription of rheological layering (relation between applied stress and deformation as a function of depth) but must be tailored to the time scale and tectonic

  7. New type of brittle deformations: two-axial turn structure of fractures in the Kovdor carbonatite intrusion (NW Russia)

    Zhirov, Dmitry


    undulation induced by the generalized plane estimated at ±1 meter. The poles of the mapped planes are plotted in the stereogram and compared with model calculations while the planes themselves are visualized in a 3D model. The behavior of the fissure selection in the stereogram and in the 3D model fully corresponds to the laws of two-axial codirectional turn of fractures. This is a new type of brittle deformations, which is of significance for the interpretation of evolutional features and modern state of the stress field in the Kovdor central-type carbonatite intrusion.

  8. Studies of Stable Octupole Deformations in the Radium Region


    The purpose of the present project is to locate and identify states in the atomic nuclei possessing stable pearshaped octupole deformation. Such states, formally related to the structures known in molecular physics, manifest themselves as families of parity doublets in odd nuclei.\\\\ \\\\ The best possibilities for observing stable octupole deformations are offered in the Ra-region. Both theoretical calculations and experimental indications support such expectations. Such indications are the non-observation of two-phonon octupole vibrational states in the ISOLDE studies of the even-even radium nuclei, and the reversed sign of the decoupling factor of the ground state band in |2|2|5Ra observed in the single-neutron transfer reactions. In order to establish the predicted strong E1 and E3-transitions between the parity doublets in odd nuclei with stable octupole deformations it is proposed to study conversion electrons in odd-mass francium radium and radon isotopes following the @b-decay of francium and astatine. \\...

  9. Dimensions of the human sclera: Thickness measurement and regional changes with axial length.

    Norman, Richard E; Flanagan, John G; Rausch, Sophie M K; Sigal, Ian A; Tertinegg, Inka; Eilaghi, Armin; Portnoy, Sharon; Sled, John G; Ethier, C Ross


    Scleral thickness, especially near the region of the optic nerve head (ONH), is a potential factor of interest in the development of glaucomatous optic neuropathy. Our goal was to characterize the scleral thickness distribution and other geometric features of human eyes. Eleven enucleated human globes (7 normal and 4 ostensibly glaucomatous) were imaged using high-field microMRI, providing 80 microm isotropic resolution over the whole eye. The MRI scans were segmented to produce 3-D corneoscleral shells. Each shell was divided into 15 slices along the anterior-posterior axis of the eye, and each slice was further subdivided into the anatomical quadrants. Average thickness was measured in each region, producing 60 thickness measurements per eye. Hierarchical clustering was used to identify trends in the thickness distribution, and scleral geometric features were correlated with globe axial length. Thickness over the whole sclera was 670 +/- 80 microm (mean +/- SD; range: 564 microm-832 microm) over the 11 eyes. Maximum thickness occurred at the posterior pole of the eye, with mean thickness of 996 +/- 181 microm. Thickness decreased to a minimum at the equator, where a mean thickness of 491 +/- 91 microm was measured. Eyes with a reported history of glaucoma were found to have longer axial length, smaller ONH canal dimensions and thinner posterior sclera. Several geometrical parameters of the eye, including posterior scleral thickness, axial length, and ONH canal diameter, appear linked. Significant intra-individual and inter-individual variation in scleral thickness was evident. This may be indicative of inter-individual differences in ocular biomechanics. Copyright 2009 Elsevier Ltd. All rights reserved.

  10. Axial guided wave technique for rapid inspection of the "Noodle" regions in a stiffened composite component

    Manogharan, Prabhakaran; Rajagopal, Prabhu; Balasubramaniam, Krishnan


    Composite structures are used in a wide variety of applications. The use of stiffened composites is common in aerospace box-like components and provides the additional stiffness required. Examples of such stiffened structural geometries include airfoils, fuselage, wing box, tail section, etc. The inspection of the radius filler "Noodle" that fills the interface between skin and stiffener has been of great concern to the aerospace composites industry. This paper describes the 3D FEM models of the ultrasonic axially propagating guided wave modes. Additionally, the models were used for understanding their confinement in the Noodle region, their leakage to the remaining sections of the component and their interaction with defects of different types, sizes and their locations along Noodle region. The ultrasonic guided wave modes that propagate along the length of the Noodle were identified using the 3D finite element model. These simulations were validated using graphite-epoxy test coupons and components from aerospace industry.

  11. Development of regional liquefaction-induced deformation hazard maps

    Rosinski, A.; Knudsen, K.-L.; Wu, J.; Seed, R.B.; Real, C.R.; ,


    This paper describes part of a project to assess the feasibility of producing regional (1:24,000-scale) liquefaction hazard maps that are based-on potential liquefaction-induced deformation. The study area is the central Santa Clara Valley, at the south end of San Francisco Bay in Central California. The information collected and used includes: a) detailed Quaternary geological mapping, b) over 650 geotechnical borings, c) probabilistic earthquake shaking information, and d) ground-water levels. Predictions of strain can be made using either empirical formulations or numerical simulations. In this project lateral spread displacements are estimated and new empirical relations to estimate future volumetric and shear strain are used. Geotechnical boring data to are used to: (a) develop isopach maps showing the thickness of sediment thatis likely to liquefy and deform under earthquake shaking; and (b) assess the variability in engineering properties within and between geologic map units. Preliminary results reveal that late Holocene deposits are likely to experience the greatest liquefaction-induced strains, while Holocene and late Pleistocene deposits are likely to experience significantly less horizontal and vertical strain in future earthquakes. Development of maps based on these analyses is feasible.

  12. Deformation Behavior of Ultra-low Carbon Steel in Ferrite Region during Warm Processing

    XU Guang; CHEN Zhenye; LIU Li; YU Shengfu


    The hot deformation experiments of ultra-low carbon steel in ferrite range were carried out ina hot simulator in order to research hot deformation behaviors of ultra-low carbon steel in ferrite range at low temperature.The results show that the influences of deformation parameters on flow stress are different to those in austenitic deformation.The deformation characteristic parameters were calculated for ultra-low carbon steel in ferrite region.The flow stress equation for ultra-low carbon steel in ferritic deformation at low temperature was obtained.

  13. Nonlocal axial load-bearing capacity of two neighboring perpendicular single-walled carbon nanotubes accounting for shear deformation

    Kiani, Keivan


    This study is devoted to examine load-bearing capacity of a nanosystem composed of two adjacent perpendicular single-walled carbon nanotubes (SWCNTs) which are embedded in an elastic matrix. Accounting for the nonlocality and the intertube van der Waals forces, the governing equations are established based on the nonlocal Euler-Bernoulli, Timoshenko, and higher-order beam theories. These are sets of coupled integro-ordinary differential equations whose analytical solutions are unavailable. Hence, an efficient meshless methodology is proposed and the discrete governing equations are obtained via Galerkin approach. By solving the resulting set of eigenvalue equations, the axial buckling load of the elastically embedded nanosystem is evaluated. The roles of the radius and slenderness ratio of the constitutive SWCNTs, free distance between two tubes, small-scale parameter, aspect ratio, transverse and rotational stiffness of the surrounding matrix on the axial buckling load of the nanosystem are comprehensively addressed. The obtained results can be regarded as a pivotal step for better understanding the mechanism of elastic buckling of more complex systems such as elastically embedded-orthogonal membranes or even forests of SWCNTs.

  14. Correction of static axial alignment in children with knee varus or valgus deformities through guided growth: Does it also correct dynamic frontal plane moments during walking?

    Böhm, Harald; Stief, Felix; Sander, Klaus; Hösl, Matthias; Döderlein, Leonhard


    Malaligned knees are predisposed to the development and progression of unicompartmental degenerations because of the excessive load placed on one side of the knee. Therefore, guided growth in skeletally immature patients is recommended. Indication for correction of varus/valgus deformities are based on static weight bearing radiographs. However, the dynamic knee abduction moment during walking showed only a weak correlation to malalignment determined by static radiographs. Therefore, the aim of the study was to measure the effects of guided growth on the normalization of frontal plane knee joint moments during walking. 15 legs of 8 patients (11-15 years) with idiopathic axial varus or valgus malalignment were analyzed. 16 typically developed peers served as controls. Instrumented gait analysis and clinical assessment were performed the day before implantation and explantation of eight-plates. Correlation between static mechanical tibiofemoral axis angle (MAA) and dynamic frontal plane knee joint moments and their change by guided growth were performed. The changes in dynamic knee moment in the frontal plane following guided growth showed high and significant correlation to the changes in static MAA (R=0.97, pknee moment before treatment showed a more pathological one after treatment. In conclusion, the changes in the dynamic load situation during walking can be predicted from the changes in static alignment. If pre-surgical gait analysis reveals a natural load situation, despite a static varus or valgus deformity, the intervention must be critically discussed.

  15. Surface Deformation Monitoring in Permafrost Regions of Tibetan Plateau Based on Alos Palsar Data

    Chen, L. M.; Qiao, G.; Lu, P.


    The permafrost region of Qinghai-Tibet Plateau is widely distributed with the freeze/thaw processes that cause surface structural damage. The differential interferometry synthetic aperture radar (DInSAR) can detect large scale surface deformation with high precision, thus can be used to monitor the freeze/thaw processes of frozen soil area. In this paper, the surface deformation pattern of Qinghai-Tibet railway was analyzed by using the PALSAR 1.0 raw data of the ALOS satellite (L band) and 90m resolution SRTM DEM data, with the help of two-pass DInSAR method in GAMMA software, and the differential interferograms and deformation maps were obtained accordingly. Besides, the influence of temperature, topography and other factors on deformation of frozen soil were also studied. The following conclusions were obtained: there is a negative correlation between deformation and temperature, and there is a delay between the deformation change and that of temperature; deformation and elevation are positively correlated; the permafrost deformation is also affected by solar radiation that could form variable amplitude variation.

  16. Deformation of Ne isotopes in the island-of-inversion region

    Sumi, Takenori; Tagami, Shingo; Kimura, Masaaki; Matsumoto, Takuma; Ogata, Kazuyuki; Shimizu, Yoshifumi R; Yahiro, Masanobu


    The deformation of Ne isotopes in the island-of-inversion region is determined by the double-folding model with the Melbourne $g$-matrix and the density calculated by the antisymmetrized molecular dynamics (AMD). The double-folding model reproduces, with no adjustable parameter, the measured reaction cross sections for the scattering of $^{28-32}$Ne from $^{12}$C at 240MeV/nucleon. The quadrupole deformation thus determined is around 0.4 in the island-of-inversion region and $^{31}$Ne is a halo nuclei with large deformation. We propose the Woods-Saxon model with a suitably chosen parameterization set and the deformation given by the AMD calculation as a convenient way of simulating the density calculated directly by the AMD. The deformed Woods-Saxon model provides the density with the proper asymptotic form. The pairing effect is investigated, and the importance of the angular momentum projection for obtaining the large deformation in the island-of-inversion region is pointed out.

  17. Dense seismic networks as a tool to characterize active faulting in regions of slow deformation

    Custódio, Susana; Arroucau, Pierre; Carrilho, Fernando; Cesca, Simone; Dias, Nuno; Matos, Catarina; Vales, Dina


    The theory of plate tectonics states that the relative motion between lithospheric plates is accommodated at plate boundaries, where earthquakes occur on long faults. However, earthquakes with a wide range of magnitudes also occur both off plate boundaries, in intra-plate settings, and along discontinuous, diffuse plate boundaries. These settings are characterized by low rates of lithospheric deformation. A fundamental limitation in the study of slowly deforming regions is the lack of high-quality observations. In these regions, earthquake catalogs have traditionally displayed diffuse seismicity patterns. The location, geometry and activity rate of faults - all basic parameters for understanding fault dynamics - are usually poorly known. The dense seismic networks deployed in the last years around the world have opened new windows in observational seismology. Although high-magnitude earthquakes are rare in regions of slow deformation, low-magnitude earthquakes are well observable on the time-scale of these deployments. In this presentation, we will show how data from dense seismic deployments can be used to characterize faulting in regions of slow deformation. In particular, we will present the case study of western Iberia, a region undergoing low-rate deformation and which has generated some of the largest earthquakes in Europe, both intraplate (mainland) and interplate (offshore). The methods that we employ include automated earthquake detection methods to lower the completeness magnitude of catalogs, earthquake relocations, focal mechanisms patterns, waveform similarity and clustering analysis.

  18. Inherited weaknesses control deformation in the flat slab region of Central Argentina

    Stevens, A.; Carrapa, B.; Larrovere, M.; Aciar, R. H.


    The Sierras Pampeanas region of west-central Argentina has long been considered a geologic type-area for flat-slab induced thick-skinned deformation. Frictional coupling between the horizontal subducting plate and South American lithosphere from ~12 Ma to the present provides an obvious causal mechanism for the basement block uplifts that characterize this region. New low temperature thermochronometry data show basement rocks from the central Sierras Pampeanas (~ longitude 66 ̊ W) including Sierras Cadena de Paiman, Velasco and Mazan retain a cooling history of Paleozoic - Mesozoic tectonics events. Results from this study indicate that less than 2 km of basement has been exhumed since at least the Mesozoic. These trends recorded by both apatite fission track (AFT) and apatite helium (AHe) thermochronometry suggest that recent Mio-Pliocene thick-skinned deformation associated with flat-slab subduction follow inherited zones of weakness from Paleozoic terrane sutures and shear zones and Mesozoic rifting. If a Cenozoic foreland basin exisited in this region, its thickness was minimal and was controlled by paleotopography. Pre-Cenozoic cooling ages in these ranges that now reach as high as 4 km imply significant exhumation of basement rocks before the advent of flat slab subduction in the mid-late Miocene. It also suggests that thick-skinned deformation associated with flat slab subduction may at least be facilitated by inherited crustal-scale weaknesses. At the most, pre-existing zones of weakness may be required in regions of thick-skinned deformation. Although flat-slab subduction plays an important role in the exhumation of the Sierras Pampeanas, it is likely not the sole mechanism responsible for thick-skinned deformation in this region. This insight sheds light on the interpretation of modern and ancient regions of thick-skinned deformation in Cordilleran systems.

  19. Deformation behavior of Zr-based bulk metallic glass and composite in the supercooled liquid region


    A Zr-based bulk metallic glass (BMG) with a composition of (Zr75Cu25)78.5Ta4Ni10Al7.5 and a bulk metallic glass matrix composite (BMGC) with a composition of (Zr75Cu25)74.5Ta8Ni10Al7.5 have been prepared by copper-mold casting. The compres-sive deformation behavior of the BMG and BMGC was investigated in the super-cooled region at different temperatures and various strain rates ranging from 8×10-4s-1 to 8×10-2s-1. It was found that both the strain rate and test temperature signifi-cantly affect the deformation behavior of the two alloys. The deformation follows Newtonian flow at low strain rates but non-Newtonian flow at high strain rates. The deformation mechanism for the two kinds of alloys was discussed in terms of the transition state theory.

  20. Three evolutionary stages of the collision orogenic deformation in the Middle Yangtze Region


    A discussion of collision orogenic deformation has been made for the Middle Yangtze Region. Based on its deformation assemblage orders, three developing stages are classified successively as compression thrust uplift, strike-slip escape rheology and tension extension inversion. The collision orogenesis of the studied region has been divided into three developing periods of initial, chief and late orogeny. Based on the data from Wugong Mts., Jiuling Mts. and Xuefeng Mts.,for each stage, its variation of stress and strain axes, the conversion of joint fractures and their relative tectonic evolution are described, models are plotted and corresponding explanations are made for the rock chronology dating value in the same tectonic period.

  1. Tectonophysics map of discontinuous deformation of Rybnik region

    Głogowska Magdalena


    Full Text Available In this paper, a Tectonophysics map of Rybnik region is presented which is based on the method of determining the direction of the trajectory of the principal stresses in the rock mass and axis orientation of these stresses. This method is used in tectonophysics and is based on the character and parameters of faults. The whole map of Rybnik region encompasses an area of active mines: Rydułtowy-Anna, Marcel, Chwałowice, Jankowice as well as closed ones: Rymer and 1 May of Marcel mine. The paper presents only some fragments of the maps made for the four fault systems and a collective map of tectonophysic, i.e., showing chart areas of compaction for all the systems. The tectonophysics map was made to a scale of 1:20 000. Before the proper work which was the reconstruction of the compaction zone, preparatory work was done. This consisted of updates in 2013 of the tectonics of this area. As a result, tectonic maps were obtained where faults were projected on one level to get their proper azimuth and their inclination. So, a map was made which was used to separate four fault systems arising in similar conditions of stress. Next followed the reconstruction of the main stress fields, which was the cause of faults. On the map there are plotted trajectories showing minimum stress (σ3 and areas of compaction. The maps thus constructed will be used for further studies on the stress spreading and the impact of these areas for geomechanical properties.

  2. Energy dissipation in the blade tip region of an axial fan

    Bizjan, B.; Milavec, M.; Širok, B.; Trenc, F.; Hočevar, M.


    A study of velocity and pressure fluctuations in the tip clearance flow of an axial fan is presented in this paper. Two different rotor blade tip designs were investigated: the standard one with straight blade tips and the modified one with swept-back tip winglets. Comparison of integral sound parameters indicates a significant noise level reduction for the modified blade tip design. To study the underlying mechanisms of the energy conversion and noise generation, a novel experimental method based on simultaneous measurements of local flow velocity and pressure has also been developed and is presented here. The method is based on the phase space analysis by the use of attractors, which enable more accurate identification and determination of the local flow structures and turbulent flow properties. Specific gap flow energy derived from the pressure and velocity time series was introduced as an additional attractor parameter to assess the flow energy distribution and dissipation within the phase space, and thus determines characteristic sources of the fan acoustic emission. The attractors reveal a more efficient conversion of the pressure to kinetic flow energy in the case of the modified (tip winglet) fan blade design, and also a reduction in emitted noise levels. The findings of the attractor analysis are in a good agreement with integral fan characteristics (efficiency and noise level), while offering a much more accurate and detailed representation of gap flow phenomena.

  3. Estimation of GNSS Multiscale Strain Field and Detection of Regional Crustal Deformation

    XU Keke


    Full Text Available Using GNSS data,the estimation model for GNSS multiscale strain field was established based on spherical wavelet. The key technologies for wavelet center location, wavelet scale choices and regularization parameter calculation were discussed in detail. For further testing the correctness of the model, the simulated data in locked fault areas was generated according to negative dislocation theory. With spherical wavelet model, the strain field in locked strike-slip fault areas was estimated,and the results agreed well with the characteristics of actual crustal deformation. Meanwhile, the experiments on crustal deformation anomaly detection with multiscale strain field were completed. The results showed that the small fault deformation of 50 km appeared obviously in the small scale(8th scale stain field, but there wasn't signals in the large scale (4 to 7 scale. The large fault deformation of 150 km only showed a part of information in the small scale (8th scale stain field, but showed more completely and clearly in the large scale(4 to 7 scale.So it's concluded that crustal deformation of different spatial coverage scope embody in the different scales strain field, and the small scale strain field have the ability to detect regional deformation anomaly.

  4. Reduction of longitudinal axial residual stresses in near-root region of circumferential joint of steam pipeline in technological way

    V. M. Prokhorenko


    Full Text Available The paper proposes a variant for solving the problem of reduction of longitudinal residual stresses in near-root region of a circumferential welded joint of section of steam pipeline by FEM simulation of the stress-strain state of repaired section of a circumferential weld in the zone of lack of root penetration on a thin-wall shell of 89 mm diameter and 6 mm wall thickness from steel 20. The result of solving the problem is total distribution of stresses and residual plastic deformations in the repaired zone.

  5. Correlation between distribution and shape of VMS deposits and regional deformation patterns, Skellefte district, northern Sweden

    Bauer, Tobias E.; Skyttä, Pietari; Hermansson, Tobias; Allen, Rodney L.; Weihed, Pär


    The Skellefte district in northern Sweden is host to abundant volcanogenic massive sulphide (VMS) deposits comprising pyritic, massive, semi-massive and disseminated Zn-Cu-Au ± Pb ores surrounded by disseminated pyrite and with or without stockwork mineralisation. The VMS deposits are associated with Palaeoproterozoic upper crustal extension (D1) that resulted in the development of normal faults and related transfer faults. The VMS ores formed as sub-seafloor replacement in both felsic volcaniclastic and sedimentary rocks and partly as exhalative deposits within the uppermost part of the volcanic stratigraphy. Subsequently, the district was subjected to deformation (D2) during crustal shortening. Comparing the distribution of VMS deposits with the regional fault pattern reveals a close spatial relationship of VMS deposits to the faults that formed during crustal extension (D1) utilising the syn-extensional faults as fluid conduits. Analysing the shape and orientation of VMS ore bodies shows how their deformation pattern mimics those of the hosting structures and results from the overprinting D2 deformation. Furthermore, regional structural transitions are imitated in the deformation patterns of the ore bodies. Plotting the aspect ratios of VMS ore bodies and the comparison with undeformed equivalents in the Hokuroko district, Japan allow an estimation of apparent strain and show correlation with the D2 deformation intensity of the certain structural domains. A comparison of the size of VMS deposits with their location shows that the smallest deposits are not related to known high-strain zones and the largest deposits are associated with regional-scale high-strain zones. The comparison of distribution and size with the pattern of high-strain zones provides an important tool for regional-scale mineral exploration in the Skellefte district, whereas the analysis of ore body shape and orientation can aid near-mine exploration activities.

  6. Interseismic deformation associated with three-dimensional faults in the greater Los Angeles region, California

    Marshall, Scott T.; Cooke, Michele L.; Owen, Susan E.


    Existing interseismic models are not well-suited to simulate deformation within the network of finite, intersecting, nonplanar faults observed in the greater Los Angeles region. Instead of applying fault slip rates to a model a priori, we allow three-dimensional fault surfaces to interact and accumulate mechanically viable slip distributions and then use the deep nonseismogenic portion of slip to calculate interseismic deformation. We apply this approach to the Los Angeles region and find that the geologic timescale model results match well geologic slip rate data and the interseismic timescale model results match well the heterogeneous GPS velocity pattern in the Los Angeles region. Model results suggest that localized geodetic convergence in the San Gabriel basin can be achieved with slip on multiple active fault surfaces in the Los Angeles region including relatively fast slip on the Sierra Madre fault and slow slip on the Puente Hills thrusts, in agreement with geologic data. The ability of the three-dimensional model to reproduce well both geologic slip rates and interseismic geodetic velocity patterns suggests that current day contraction rates in the greater Los Angeles region are compatible with long-term geologic deformation rates and disputes suggestions of significant temporal variations in fault slip rates inferred from existing investigations.

  7. Hydrodynamic instabilities in the developing region of an axially rotating pipe flow

    Miranda-Barea, A; Fabrellas-García, C; Parras, L; Pino, C del, E-mail: [Universidad de Málaga, Escuela Técnica Superior de Ingeniería Industrial, Ampliación Campus de Teatinos, 29071, Málaga, España (Spain)


    We conduct experiments in a rotating Hagen–Poiseuille flow (RHPF) through flow visualizations when the flow becomes convectively and absolutely unstable at low-to-moderate Reynolds numbers, Re. We characterize periodic patterns at a very high swirl parameter, L, when the flow overcomes the absolutely unstable region. These non-steady helical filaments wrapped around the axis appear in the developing region of the pipe. Experimentally, we compute the onset of these oscillations in the (L, Re)-plane finding that the rotation rate decreases as the Reynolds number increases in the process of achieving the time-dependent state. Additionally, we report information regarding frequencies and wavelengths that appear downstream of the rotating pipe for convectively and absolutely unstable flows, even for very high swirl parameters at which the flow becomes time-dependent in the developing region. We do not observe variations in the trends of these parameters, so these hydrodynamic instabilities in the developing region do not affect the unstable travelling waves downstream of the pipe. (paper)

  8. Estimation of transient deformation on cGPS measurements at Taiwan region: Implications for tectonic and surface processes

    Chen, K. H.; Chan, Y. C.


    Transient deformation on geodetic time series is usually caused by the tectonic or surface processes. Surface processes include multiple durations that could be trapped or ignored using general time series analysis. We first recognize overall transient signals in Taiwan region recorded by continuous GPS (cGPS) networks. Sparse estimation techniques and Bi-splines function are used to detect the signals on cGPS time series then estimate the parameters. Our study analyzes the transient deformation by using a multi-dataset of the cGPS, seismogram, digital terrain model (DTM), and rainfall gauges. We establish a systematic classification by weighting both the empirical trigger factors and regional criterion to classify the signals into seven types. Spatial and temporal characteristics of transient deformation show three major contributions in Taiwan region including the seismic-related, landslides-related, and slow-slip transients. The cGPS networks in Taiwan region show long-term transient deformation at rates 2-68 mm/yr, ~14%-75% of their tectonic interseismic velocities. Tectonic and surface processes involve ~38%-85% and ~15%-62%, respectively, in the transient deformation under different geological units of Taiwan region. The lack of consideration for the transient deformation in surface processes would underestimate their biases on tectonic interseismic velocity. Statistical linking between cGPS transient deformation, tectonic and surface processes of Taiwan indicate that earthquake, typhoon, and topography play important roles in the occurrence of transient deformation.

  9. Axial symmetry around the recoil axis for the 238U(α, α'f) reaction and the fission probability in the giant resonance region

    Leo, R. de; Harakeh, M.N.; Micheletti, S.; Plicht, J. van der; van der Woude, Adriaan; David, P.; Janszen, H.


    A measurement of the α-spectrum in the region of the isoscalar giant resonances from 238U at Eα = 120 MeV in coincidence with out-of-plane fission fragments shows the validity of the hypothesis of axial symmetry with respect to the recoil axis. Similar to what was observed in previous in-plane

  10. Dynamics of the Balkans deformation : regional impact of the Western Hellenic subduction-collision transition

    Métois, Marianne; D'Agostino, Nicola; Copley, Alex


    The increasing number of GPS measurements in the Balkan Peninsula over the last decades has brought new insights on the kinematic of the Eurasian plate there, revealing a significant ( 5 mm/yr) clockwise rotation motion of the entire region around the Scutari-Pec line in North Albania [Métois et al. 2015]. The focal mechanisms of recent earthquakes in this seismically active area are consistent with this deformation pattern. In this study, we use simple dynamic models based on the thin viscous sheet approximation to test the influence of realistic kinematic boundary conditions and gradients of gravitational potential energy on the predicted surface deformation in the region. In addition, we compare the surface velocity field with maps of azimuthal anisotropy at depth to assess whether mantle motions may drive part of the observed lithosphere deformation. We show that the observed shearing and rotation around Albania can be explained at the first order by kinematic boundary conditions applied on a viscous lithosphere (η ˜ 2.1021Pa.s), while GPE gradients may control the smaller-scale patterns of deformation. Our models appear to be very sensitive to the abrupt velocity-change imposed across the Kefalonia fault in northern Greece where the subduction to collision transition takes place. We propose that the large-scale shearing of the region observed in the GPS data results mainly from this lithospheric tearing, that is one of the most active structure in the area. This hypothesis implies that the slab tearing initiation would have been an important controlling factor on the tectonic history of the Balkans and that the current velocity gradient across the Kefalonia fault is probably sufficient to trigger a large scale shearing propagating up to central Serbia.

  11. Sytematics of dynamic moment of inertia in super-deformed bands in Mass ~150 region

    Roy, S


    An empirical semi-classical model have been proposed to investigate the nature of dynamic moment-of-inertia , of the super-deformed (SD) bands in nuclei of mass 150 region. The model incorporates an additional frequency dependent distortion, to the dynamic moment-of-inertia term akin to a vibrational component to explain the extreme spin structure of these bands. Using this model two separate components to the dynamic moment of inertia, $\\Im^{(2)}$ have been identified for the SD band structure for the mass 150 region. Three distinct nature of the moment-of-inertia, also have been identified using the two parameter model.

  12. Co-axial superposed folding and inverted regional metamorphism in the Tonga Formation: Cretaceous accretionary thrust tectonics in the Cascades crystalline core

    Luke, Jensen; Lebit, Hermann; Paterson, Scott; Miller, Robert; Vernon, Ron


    The Cascades crystalline core forms part of the Cretaceous magmatic belt of western North America and exposes a crustal section composed of primarily tonalitic plutons that intruded siliciclastic metasediments of an arc-derived accretional system, and local meta-basalt/chert sequences. This study is the first attempt to correlate the well understood intrusive and P-T-t history of the metasedimentary and plutonic terrane with the kinematics and tectonic boundary conditions by rigorous analysis of structures documented in the Tonga Formation exposed at the western edge of the core. The Tonga Formation comprises pelite-psammite metasediments, which increase from greenschist ( 300-350° C) to amphibolite grade ( 500-600° C) from south to north. This metamorphic gradient is inverted relative to a major westward verging and downward facing fold system that dominates the internal architecture of the formation and implies that the initial regional metamorphic signature was established prior to the early fold generation. Subsequent co-axial fold superposition is seen as a consequence of the persistent accretional west-vergent thrusting in the foreland of the magmatic arc. The central section of the Cascades Range, exposed in western Washington, forms part of the Cretaceous accretional/magmatic arc extending over 4,000 km along western North America from Baja California to British Columbia (Fig. 1a) (e.g. Misch, 1966; Brown, 1987; Tabor et al., 1989). Two models exist for the evolution of the Cascades crystalline core with one invoking magmatic loading (e.g. Brown and Walker, 1993) as the major cause for rapid loading, consequent regional metamorphism and vertical uplift (Evans and Berti, 1986). Conversely, other workers favor a model that suggests loading as a consequence of tectonic, thrust-related thickening, followed by rapid exhumation of the exposed crustal section of 10 to 40 km paleodepth (e.g. Matzel, 2004; Patterson et al., 2004; Stowell et al., 2007). In this

  13. Algorithmic localisation of noise sources in the tip region of a low-speed axial flow fan

    Tóth, Bence; Vad, János


    An objective and algorithmised methodology is proposed to analyse beamform data obtained for axial fans. Its application is demonstrated in a case study regarding the tip region of a low-speed cooling fan. First, beamforming is carried out in a co-rotating frame of reference. Then, a distribution of source strength is extracted along the circumference of the rotor at the blade tip radius in each analysed third-octave band. The circumferential distributions are expanded into Fourier series, which allows for filtering out the effects of perturbations, on the basis of an objective criterion. The remaining Fourier components are then considered as base sources to determine the blade-passage-periodic flow mechanisms responsible for the broadband noise. Based on their frequency and angular location, the base sources are grouped together. This is done using the fuzzy c-means clustering method to allow the overlap of the source mechanisms. The number of clusters is determined in a validity analysis. Finally, the obtained clusters are assigned to source mechanisms based on the literature. Thus, turbulent boundary layer - trailing edge interaction noise, tip leakage flow noise, and double leakage flow noise are identified.

  14. Axial 3D region of interest reconstruction using weighted cone beam BPF/DBPF algorithm cascaded with adequately oriented orthogonal butterfly filtering

    Tang, Shaojie; Tang, Xiangyang


    Axial cone beam (CB) computed tomography (CT) reconstruction is still the most desirable in clinical applications. As the potential candidates with analytic form for the task, the back projection-filtration (BPF) and the derivative backprojection filtered (DBPF) algorithms, in which Hilbert filtering is the common algorithmic feature, are originally derived for exact helical and axial reconstruction from CB and fan beam projection data, respectively. These two algorithms have been heuristically extended for axial CB reconstruction via adoption of virtual PI-line segments. Unfortunately, however, streak artifacts are induced along the Hilbert filtering direction, since these algorithms are no longer accurate on the virtual PI-line segments. We have proposed to cascade the extended BPF/DBPF algorithm with orthogonal butterfly filtering for image reconstruction (namely axial CB-BPP/DBPF cascaded with orthogonal butterfly filtering), in which the orientation-specific artifacts caused by post-BP Hilbert transform can be eliminated, at a possible expense of losing the BPF/DBPF's capability of dealing with projection data truncation. Our preliminary results have shown that this is not the case in practice. Hence, in this work, we carry out an algorithmic analysis and experimental study to investigate the performance of the axial CB-BPP/DBPF cascaded with adequately oriented orthogonal butterfly filtering for three-dimensional (3D) reconstruction in region of interest (ROI).

  15. Axial myopathy

    Witting, Nanna; Andersen, Linda K; Vissing, John


    musculature involvement in the majority of myopathies in which paraspinal musculature was examined. Even in diseases named after a certain pattern of non-axial muscle affection, such as facioscapulohumeral and limb girdle muscular dystrophies, affection of the axial musculature was often severe and early...

  16. Characteristics of Recent Horizontal Crustal Movement and Tectonic Deformation in the Northwest China Region

    Liu Wenyi; Wang Shuangxu; Wang Wenping; Zhang Xiaoliang; Cui Duxin; Xue Fuping


    Making use of observation data of GPS in the Northwest China region and infrared distancemeasurements crossing the Qilian-Longshoushan fault zone up to 2004, aided by the least square collocation and inversion of negative dislocation model for the boundaries of elastic blocks and the singular force-source, the dynamic evolution features of deformation and strain fields before and after the Ms = 8. 1 earthquake on the west of Kunlun Mountains Pass,especially the recent tectonic deformation and stress field status three years after this earthquake are studied. The possible regions or segments of active blocks and their boundaries reflecting accumulation background of high strain energy of producing earthquakes over middle magnitude, are obtained, as well as the potential epicenter. The results show that after short-term relaxation and adjustment in the northern margin of Qinghai-Xizang (Tibet) block after the Ms = 8. 1 earthquake, the main control action of background field of northeastward pushing of Indian plate is now recovering. Moreover, the following regions are found to have the background of high strain energy accumulation. They are the middle segment of the northern Tianshan fault zone and its meeting region with the western segment, the middle and western segments of southern Tianshan fault zone and the meeting region with Western Kunlun fault zone, the middle segment of Altun fault, the middle-eastern segment of Qilianshan fault zone and its meeting region with Haiyuan fault, the meeting region of northern margin fault of west Qinling Range and the southeastward expanding line of Zhuanglanghe fault; The Linze and Haiyuan areas also see accumulation of strain energy to some degree.

  17. 圆柱轴类零件径向与轴向热变形异常现象研究%Study on Abnormal Phenomena of Radial and Axial Thermal Deformation of Cylindrical Parts

    罗哉; 陆艺; 郭斌; 范伟军


    A phenomenon was found by experimental results that the same size of cylindrical parts had different radial and axial thermal deformations under the same conditions. And the traditional therodynamic theory could not explain this phenomenon. The relationship between volume expansion coefficient and linear expansion coefficient of crystal was built up by using the Lattice vibration theory of solid--state physics. Based on this relationship, a radial thermal deformation of cylindrical model was set up. The model was different with the traditional model. The experimental results show that the value which calculated by the model is closer to the experimental results than that by the tradition- al model, and cylindrical parts have different radial and axial thermal expansion coefficient. Tradition- al model of axial thermal deformation can not be used in micro--field when calculating the radial thermal deformation of cylindrical parts.%通过实验发现了直径和长度相同的轴在径向和轴向具有不同的热变形量,传统的热力学理论不能解释这一现象。利用固体物理学晶格振动理论,推导了晶体体积膨胀系数与线膨胀系数之间的关系;将金属材料近似为晶体材料,利用线膨胀系数与体积膨胀系数的关系并结合对材料线膨胀系数研究的成果,建立了轴类零件径向热变形模型,理论分析证实了轴类零件径向热膨胀系数与轴向热膨胀系数不同。实验结果表明:轴类零件径向热变形模型计算结果较传统热力学计算结果更接近实验结果,且径向和轴向具有不同的热膨胀系数,在高精度领域,轴类零件的径向热变形不能使用轴向热膨胀系数进行计算。

  18. Coseismic seafloor deformation in the trench region during the Mw8.8 Maule megathrust earthquake

    Maksymowicz, A.; Chadwell, C. D.; Ruiz, J.; Tréhu, A. M.; Contreras-Reyes, E.; Weinrebe, W.; Díaz-Naveas, J.; Gibson, J. C.; Lonsdale, P.; Tryon, M. D.


    The Mw 8.8 megathrust earthquake that occurred on 27 February 2010 offshore the Maule region of central Chile triggered a destructive tsunami. Whether the earthquake rupture extended to the shallow part of the plate boundary near the trench remains controversial. The up-dip limit of rupture during large subduction zone earthquakes has important implications for tsunami generation and for the rheological behavior of the sedimentary prism in accretionary margins. However, in general, the slip models derived from tsunami wave modeling and seismological data are poorly constrained by direct seafloor geodetic observations. We difference swath bathymetric data acquired across the trench in 2008, 2011 and 2012 and find ~3-5 m of uplift of the seafloor landward of the deformation front, at the eastern edge of the trench. Modeling suggests this is compatible with slip extending seaward, at least, to within ~6 km of the deformation front. After the Mw 9.0 Tohoku-oki earthquake, this result for the Maule earthquake represents only the second time that repeated bathymetric data has been used to detect the deformation following megathrust earthquakes, providing methodological guidelines for this relatively inexpensive way of obtaining seafloor geodetic data across subduction zone.

  19. Contact Region Estimation Based on a Vision-Based Tactile Sensor Using a Deformable Touchpad

    Yuji Ito


    Full Text Available A new method is proposed to estimate the contact region between a sensor and an object using a deformable tactile sensor. The sensor consists of a charge-coupled device (CCD camera, light-emitting diode (LED lights and a deformable touchpad. The sensor can obtain a variety of tactile information, such as the contact region, multi-axis contact force, slippage, shape, position and orientation of an object in contact with the touchpad. The proposed method is based on the movements of dots printed on the surface of the touchpad and classifies the contact state of dots into three types—A non-contacting dot, a sticking dot and a slipping dot. Considering the movements of the dots with noise and errors, equations are formulated to discriminate between the contacting dots and the non-contacting dots. A set of the contacting dots discriminated by the formulated equations can construct the contact region. Next, a method is developed to detect the dots in images of the surface of the touchpad captured by the CCD camera. A method to assign numbers to dots for calculating the displacements of the dots is also proposed. Finally, the proposed methods are validated by experimental results.

  20. Seismic velocity structure in the shallower part of the subducting Pacific lithosphere around the Japan Trench axial region

    Azuma, R.; Hino, R.; Ito, Y.; Yamamoto, Y.; Suzuki, K.


    We have revealed that the Vp of the oceanic crust and upper mantle of the Pacific lithosphere is significantly reduced near the axial part of the Japan Trench, from airgun-OBS seismic experiments made at the outer rise and the inner trench regions of the trench (Azuma et al., 2009). From the spatial correlation between the Vp reduction and the development of the horst- graven structure, it is suggested that the Vp reduction is possibly caused by the fracturing and water infiltration accompanying the lithospheric bending. However, in order to thoroughly understand the mechanism of the structural change, we must clarify the Vs structure of the subducting oceanic lithosphere. This study uses two different datasets. One is the data obtained by the seismic experiments described by Azuma et al. (2009). We analyzed converted S waves from the airgun source recorded on the horizontal components of OBS by a 2D ray tracing method (Zelt and Smith, 1992) and determined the Vp/Vs ratio in the Pacific lithosphere before it subducts. Another is the earthquake arrival time data. We observed inter- and intra-plate earthquakes beneath the inner trench slope by an OBS array deployed at the outer rise region and analyzed the P and S wave travel times by using a 3D ray tracing method (Zhao et al., 1992). The latter is the first attempt of estimation of seismic velocity of the slab mantle around trench axis. The results of seismic experiments show that the Vp/Vs ratio of the oceanic crustal layer 2, of the layer 3, and of the uppermost mantle at the outer rise are 2.08-2.11, 1.84-1.87 and 1.71-1.72, respectively. In comparison with the ratio of a normal oceanic lithosphere (Shinohara et al., 2008), Vp/Vs of the layer 2 at the outer rise significantly increases whereas the Vp/Vs does not show significant change either in the layer 3 or in the upper mantle. The travel time analysis of the earthquake data shows that the Vp/Vs ratio of the slab mantle beneath the trench is 1.73-1.74, which

  1. Current regional stress field and the resultant crustal deformation in SE Korea and their tectonic implication

    Kim, M. C.; Cho, H.; Son, M.


    To determine current regional stress field and to characterize the resultant crustal deformation in SE Korea, Quaternary fault, focal mechanism, and geotechnical in-situ stress data were synthetically analyzed. The Quaternary faults are extensively observed along major inherited fault zones and show compatible orientations with general trends of the inherited faults. Most of the Quaternary faults have a top-to-the-west thrust geometry and kinematics and show a tendency of upward-decreasing dip angle and upward-narrowing gouge zone. Slip-sense indicators and paleo-stress field reconstructions indicate that the faults resulted from reverse or transpressional faulting under an E-W compression. All the magnetic fabrics (AMS) of the fault gouges also indicate the prevailing reverse-slip faulting under an ENE-WNW compression. The dominant oblate magnetic fabrics parallel to fault plane and the degrees of anisotropy increasing in proportion to their oblatenesses indicate that the fabrics have formed by a progressive deformation due to continuous simple shear during the last reactivation stage as reverse faulting. The focal mechanism study in and around the Korean Peninsula show the horizontally clustered P-axes in ENE-WSW direction and the girdle-distributed T-axes in NNW trend. The geotechnical in-situ stress data in south Korea also show NE- or ENE-trending maximum horizontal stress. The current crustal deformation in Korea thus can be characterized by contractional structures produced under a regional E-W or ENE-WSW compression stress field, and most of the Quaternary faults resulted from the local re-activation of appropriately oriented inherited major faults. Considering the tectonic setting and structural features in Asia during the Neogene, the current stress regime is interpreted to have been caused by the cooperation of westward shallow subduction of Pacific Plate and collision of Indian and Eurasian continents since about 5-3.5 Ma.

  2. Regional tectonic deformation in Southern California, inferred from terrestrial geodesy and the global positioning system

    Shen, Zhengkang

    Tectonic deformation in two regions in Southern California, the Southern Coast Ranges and the Los Angeles Basin, was studied. Results show that in the Southern Coast Ranges, regional deformation is predominantly controlled by deep strike slip motion along the San Andreas Fault, at a rate of 32 plus or minus 2 mm/yr. The deep slip along the San Gregorio-Hosgri Fault is about 1-3 mm/yr, assuming a locked fault depth of 20 km. Convergence normal to the San Andreas Fault in the Southern Coast ranges is not significantly different from zero. About 5 mm/yr convergence is detected from the Santa Maria Basin. In the Los Angeles Basin area, this study demonstrates about 10 mm/yr relative motion trending northwest from San Pedro Hill to the San Gabriel Mountains. The direction of motion closely parallels to the trend of the frontal fault system at the southern margin of the San Gabriel Mountains. The basin suffers from north-south convergence and east-west extension, at a rate of about 0.07 mu rad/yr for either components. The convergence rate normal to the San Andreas across the basin is 4 plus or minus 3 mm/yr, implying smaller compression than previous estimates (e.g., Cline et al. 1984).

  3. Effect of blood donation-mediated volume reduction on regional right ventricular deformation in healthy subjects.

    Açar, Göksel; Alizade, Elnur; Avci, Anıl; Cakir, Hakan; Efe, Suleyman Cagan; Kalkan, Mehmet Emin; Tabakci, Mehmet Mustafa; Toprak, Cuneyt; Tanboğa, Ibrahim Halil; Esen, Ali Metin


    Strain (S) and strain rate (SR) are known to be altered in diseases associated with right ventricular (RV) pressure/volume overload and RV myocardial dysfunction; however determinants of S/SR are incompletely understood. The aim of this study was to examine the effect of blood donation-mediated volume reduction on regional RV deformation in healthy young adults. Study population was composed of 61 consecutive healthy subjects who were volunteers for blood donation. All underwent standard echocardiography and two-dimensional S and SR imaging by speckle tracking before and after 450 mL blood donation. We found no change in RV lateral wall SR in all three segments. However, the S in the apical and mid segments of the RV lateral wall immediately decreased after blood donation [-26.2 ± 3.3 vs. -23.2 ± 3.3 % (p subjects caused a regional difference in RV longitudinal deformation with the lower mid and apical S that was related to parameters of volume load severity. However, RV systolic SR was found to be resistant to the effects of volume depletion.

  4. Formation and coalescence of strain localized regions in ferrite phase of DP600 steels under uniaxial tensile deformation

    Alaie, A., E-mail: [Department of Mechanical Engineering, Isfahan University of Technology, Isfahan (Iran, Islamic Republic of); Kadkhodapour, J. [Department of Mechanical Engineering, Shahid Rajaee Teacher Training University, Tehran (Iran, Islamic Republic of); Institute for Materials Testing, Materials Science and Strength of Materials (IMWF), University of Stuttgart, Stuttgart (Germany); Ziaei Rad, S. [Department of Mechanical Engineering, Isfahan University of Technology, Isfahan (Iran, Islamic Republic of); Asadi Asadabad, M. [Materials Research School, Isfahan (Iran, Islamic Republic of); Schmauder, S. [Institute for Materials Testing, Materials Science and Strength of Materials (IMWF), University of Stuttgart, Stuttgart (Germany)


    In this study the key factors in the creation and coalescence of strain localization regions in dual-phase steels were investigated. An in-situ tensile setup was used to follow the microscopic deformation of ferrite phase inside the microstructure of DP600 steel. The test was continued until the specimen was very close to final failure. The captured scanning electron microscopy (SEM) micrographs enabled us to directly observe the evolution of deformation bands as a contour of strain distribution in the ferrite matrix. The image processing method was used to quantify the ferrite microscopic strains; the obtained strain maps were superimposed onto the SEM micrographs. The results revealed important deformational characteristics of the microstructure at the microscopic level. It was observed that despite the formation of slip bands inside the large grains during the early stages of deformation, the large ferrite grains did not contribute to the formation of high-strain bands until the final stages of severe necking. The behavior of voids and initial defects inside the localization bands was also studied. In the final stages of deformation, cracks were observed to preferentially propagate in the direction of local deformation bands and to coalescence with each other to form the final failure lines in the microstructure. It was observed that in the final stages of deformation, the defects or voids outside the deformation bands do not contribute to the final failure mechanisms and could be considered to be of minor importance.

  5. Calculation of axially bearing capacity of a batter pile based on mechanism of deformation compatibility%基于变形协调的斜桩轴向承载力计算方法

    张麒蛰; 卓卫东; 范立础


    In order to obtain the axial bearing capacity of a batter pile , the calculation formula for the axially bearing capacity of a batter pile was deduced based on the non-uniform distribution char-acteristics of the friction resistance around the batter pile shaft and the mechanism of pile -soil deformation compatibility .The results calculated by the proposed formula and the method given by the design code of pile were compared to explore the influence of the factors , such as pile inclina-tion, diameter, length and utmost friction resistance around pile shaft , on axial bearing capacity. The calculated results showed that the value of the pile axially bearing capacity calculated by the proposed formula decreased with the increase of pile inclination .For different pile diameters , the pile axially bearing capacity was 7%smaller than that calculated by the code's formula.The shorter of the pile length or the lesser of the utmost friction resistance of the pile was , the smaller bearing capacity calculated by the code's formula was than the values calculated by the proposed formula . Finally , with the increase of the pile length or utmost friction resistance , the value of bearing capaci-ty calculated by this proposed formula was greater than the value calculated by the code's formula. The proposed formula also takes into account of the influence of pile inclination and the mechanism of pile-soil deformation compatibility .It can be a reference to calculate axial bearing capacity of bat-ter piles.%为进一步研究斜桩轴向承载力计算方法,基于斜桩的桩周摩阻力不均匀分布的特性和桩-土受力变形协调的原则,推导了斜桩轴向承载力计算公式,通过对比本文公式与规范公式的计算结果,揭示了桩身倾角、桩径、桩长和桩侧极限摩阻力等因素对斜桩轴向容许承载力的影响规律。结果表明:鉴于规范公式未考虑斜桩桩身倾角对承载力的影响,本文公式计算得

  6. Mechanism of crustal deformation in the Sichuan-Yunnan region, southeastern Tibetan Plateau: Insights from numerical modeling

    Li, Yujiang; Liu, Shaofeng; Chen, Lianwang; Du, Yi; Li, Hong; Liu, Dongying


    The characteristics of crustal deformation and its dynamical mechanisms in the Sichuan-Yunnan region are of interest to many researchers because they can help explain the deformation pattern of the eastern Tibetan Plateau. In this paper, we employ a precise three-dimensional viscoelastic finite element model to simulate the crustal deformation in the Sichuan-Yunnan region, southeastern Tibetan Plateau. We investigate the influence of lower crustal flow and rheological variations by comparing the modeled results with GPS observations. The results demonstrate that lower crustal flow plays an important role in crustal deformation in the Sichuan-Yunnan region. The best fitting is achieved when the flow velocity of the lower crust is approximately 10-11 mm/a faster than that of the upper crust. Additionally, crustal rheological properties affect regional crustal deformation. When the viscosity of the middle and lower crust in the South China block reaches 1022 and 1023 Pa·s, respectively, the modeled results match observations well, especially for the magnitude of crustal motion within the South China block. Finally, our dynamic model shows that the maximum principal stress field of the Sichuan-Yunnan region exhibits clear zoning, gradually shifting from an approximately east-west orientation in the northern Bayan Har block to southeast in the South China block, southwest in the western Yunnan block, and a radially divergent distribution in the Middle Yunnan and Southern Yunnan blocks.

  7. Regional Longitudinal Myocardial Deformation Provides Incremental Prognostic Information in Patients with ST-Segment Elevation Myocardial Infarction.

    Tor Biering-Sørensen

    Full Text Available Global longitudinal systolic strain (GLS has recently been demonstrated to be a superior prognosticator to conventional echocardiographic measures in patients after myocardial infarction (MI. The aim of this study was to evaluate the prognostic value of regional longitudinal myocardial deformation in comparison to GLS, conventional echocardiography and clinical information.In total 391 patients were admitted with ST-Segment elevation myocardial infarction (STEMI, treated with primary percutaneous coronary intervention and subsequently examined by echocardiography. All patients were examined by tissue Doppler imaging (TDI and two-dimensional strain echocardiography (2DSE.During a median-follow-up of 5.3 (IQR 2.5-6.1 years the primary endpoint (death, heart failure or a new MI was reached by 145 (38.9% patients. After adjustment for significant confounders (including conventional echocardiographic parameters and culprit lesion, reduced longitudinal performance in the anterior septal and inferior myocardial regions (but not GLS remained independent predictors of the combined outcome. Furthermore, inferior myocardial longitudinal deformation provided incremental prognostic information to clinical and conventional echocardiographic information (Harrell's c-statistics: 0.63 vs. 0.67, p = 0.032. In addition, impaired longitudinal deformation outside the culprit lesion perfusion region was significantly associated with an adverse outcome (p<0.05 for all deformation parameters.Regional longitudinal myocardial deformation measures, regardless if determined by TDI or 2DSE, are superior prognosticators to GLS. In addition, impaired longitudinal deformation in the inferior myocardial segment provides prognostic information over and above clinical and conventional echocardiographic risk factors. Furthermore, impaired longitudinal deformation outside the culprit lesion perfusion region seems to be a paramount marker of adverse outcome.

  8. Resorptive remodeling in maxillary anterior region after bimaxillary surgery for skeletal Class III deformities.

    Lee, Paul; Kim, Yong-Il; Kim, Seong-Sik; Park, Soo-Byung; Son, Woo-Sung


    The aim of this retrospective study was to evaluate bony remodelling in the anterior region of the maxilla after bimaxillary surgery for skeletal Class III deformities preoperatively, immediately postoperatively, and 6 months postoperatively. For accurate analysis, cone-beam computed tomographic (CT) images of 29 patients (12 men and 17 women; mean age 22 (range 19 to 44) years) were used. The nasopalatine canal, unaffected by the maxillary Le Fort I osteotomy, was used for the reference points (posterosuperior, midpoint, and posteroinferior). The changes in the distance from each of the points on the nasopalatine canal to the corresponding anterior border of the maxilla were measured and analysed at the 3 stages (pbimaxillary surgery with superior maxillary movement, which suggests that the postoperative change in the position of point A is affected by operative movement as well as by postoperative relapse and bony remodelling. Copyright © 2015 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  9. Comparison of seismotomographic and thermogravitational models with distribution of the seismotectonic deformation orientations for Kamchatka region

    Bushenkova, Natalia; Kuchay, Olga; Chervov, Victor; Koulakov, Ivan


    In this study we reveal the relationships between the structure of the lithosphere, the distribution of convective flows in the upper mantle and the character of seismotectonic deformations (STD) that is especially important for regions of active continental margins. We present a comprehensive analysis of seismotomographic and thermogravitational models together with the distribution of the STD principal axes orientations for the Kamchatka region, where crustal displacements are accompanied with seismic and volcanic activity. Our previous results have shown that: the variations of the lithosphere thickness significantly affect the structure of convective flows in the upper mantle [Chervov, Chernykh, 2014]; the pattern of these flows, in turn, correlate with the distribution and the orientations of STD principal axes (for the Altai-Sayan region with surrounding areas [Bushenkova, at al., 2014]). Based on the upper mantle seismic tomography model beneath Kamchatka and adjacent regions by Koulakov et al. (2011) and taking into account the variations of the lithosphere structure, we have calculated a numerical 3D model of thermal convection in the upper mantle. Also, we have estimated the distribution of orientations of the STD principal axes. We used the focal mechanisms of 511 earthquakes occurred in the period of 1976-2015 [] in the Kamchatka region. These focal mechanisms were transformed to the 3D STD distributions based on the Riznichenko's method (1985). In this case, the STD was determined as an average seismic moment tensor of all earthquakes in a unit volume for the selected time. We found that the STD principal axes distribution is inherited for different depth layers along the entire eastern coast of Kamchatka. Abrupt changes in the orientation of the principal axes of elongation and shortening, and a change of the direction of their dipping are observed in area zone of 53.0- 54.50 N. This zone coincides with an

  10. The deformation of ice-debris landforms in the Khumbu Region from InSAR

    Schmidt, D. A.; Barker, A. D.; Hallet, B.


    We present new interferometric synthetic aperture radar (InSAR) results for the Khumbu region, Nepal, using PALSAR data from the ALOS1 satellite. Glaciers and ice-debris landforms represent a critical water resource to communities in the Himalayas and other relatively arid alpine environments. Changes in climate have impacted this resource as the volume of ice decreases. The monitoring of rock glaciers and debris covered glaciers is critical to the assessment of these natural resources and associated hazards (e.g. Glacial Lake Outburst Floods--GLOFs). Satellite data provide one means to monitor ice-containing landforms over broad regions. InSAR measures the subtle deformation of the surface, with mm precision, that is related to deformation or changes in ice volume within rock glaciers and debris-covered glaciers. While previous work in the region had used C-band (6 cm wavelength) SAR data from the ERS satellite, we utilize L-band data (24 cm) from the ALOS satellite, which provides better coherence, especially where the phase gradient is large. After processing 20 differential interferograms that span from 2008 to 2011, we focus on the 5 interferograms with the best overall coherence. Based on three 45-day interferograms and two 3-year interferograms, all of which have relatively small perpendicular baselines (glaciers. From the 3-year interferograms, we map the boundary of active movement along the perimeter of the debris-covered toe of Khumbu Glacier. Movement over this longer time period leads to a loss of coherence, clearly delimiting actively moving areas. Of particular note, active movement is detected in the glacier-moraine dam of Imja Lake, which has implications for GLOF hazard. The significant vertical relief in the Himalaya region poses a challenge for doing differential radar interferometry, as artifacts in the digital elevation model (DEM) can propagate into the differential interferograms. Additionally, large changes in topography or glacier surfaces

  11. A concept for energy harvesting from quasi-static structural deformations through axially loaded bilaterally constrained columns with multiple bifurcation points

    Lajnef, N.; Burgueño, R.; Borchani, W.; Sun, Y.


    A major obstacle limiting the development of deployable sensing and actuation solutions is the scarcity of power. Converted energy from ambient loading using piezoelectric scavengers is a possible solution. Most of the previously developed research focused on vibration-based piezoelectric harvesters which are typically characterized by a response with a narrow natural frequency range. Several techniques were used to improve their effectiveness. These methods focus only on the transducer’s properties and configurations, but do little to improve the stimuli from the source. In contrast, this work proposes to focus on the input deformations generated within the structure, and the induction of an amplified amplitude and up-converted frequency toward the harvesters’ natural spectrum. This paper introduces the concept of using mechanically-equivalent energy converters and frequency modulators that can transform low-amplitude and low-rate service deformations into an amplified vibration input to the piezoelectric transducer. The introduced concept allows energy conversion within the unexplored quasi-static frequency range (≪1 Hz). The post-buckling behavior of bilaterally constrained columns is used as the mechanism for frequency up-conversion. A bimorph cantilever polyvinylidene fluoride (PVDF) piezoelectric beam is used for energy conversion. Experimental prototypes were built and tested to validate the introduced concept and the levels of extractable power were evaluated for different cases under varying input frequencies. Finally, finite element simulations are reported to provide insight into the scalability and performance of the developed concept.

  12. Polyphase deformation and metamorphism of the Cuiabá group in the Poconé region (MT, Paraguay Fold and Thrust Belt: kinematic and tectonic implications

    Bruno Rodrigo Vasconcelos

    Full Text Available Several deformation models have been proposed for the Paraguay Belt, which primarily differ in the number of phases of deformation, direction of vergence and tectonic style. Structural features presented in this work indicate that the tectonics was dominated by low dip thrust sheets in an initial phase, followed by two progressive deformation phases. The first phase of deformation is characterized by a slate cleavage and axial plane of isoclinal recumbent folds with a NE axial direction, with a recrystallization of the minerals in the greenschist facies associated with horizontal shear zones with a top-to-the-SE sense of movement. The second stage shows vergence towards the NW, characterized by crenulation cleavage axial plane to F2 open folds over S0 and S1, locally associated with reverse faults. The third phase of deformation is characterized by subvertical faults and fractures with a NW direction showing sinistral movement, which are commonly filled by quartz veins. The collection of tectonic structures and metamorphic paragenesis described indicate that the most intense deformation at the deeper crustal level, greenschistfacies, occurred during F1, which accommodated significant crustal shortening through isoclinal recumbent folds and shear zones with low dip angles and hangwall movement to the SE, in a thin-skinned tectonic regime. The F2 deformation phase was less intense and had a brittle to ductile behavior that accommodated a slight shortening through normal open subvertical folds, and reverse faults developed in shallower crustal level, with vergence towards the Amazonian Craton. The third phase was less pervasive, and the shortening was accommodated by relief subvertical sinistral faults.

  13. Lithospheric architecture and deformation of NE Tibet: New insights on the interplay of regional tectonic processes

    Guo, Xiaoyu; Gao, Rui; Li, Sanzhong; Xu, Xiao; Huang, Xingfu; Wang, Haiyan; Li, Wenhui; Zhao, Shujuan; Li, Xiyao


    GPS measurements indicate rapid lateral extrusion of the NE Tibetan Plateau, which causes active NE-directed crustal shortening and has initiated oblique shearing along the margins of NE Tibet. However, the Tibetan highlands terminate around 103°E longitude and topographic relief disappears to the northeast. The exact reasons for this drop in elevation remain obscure due to widespread Tertiary sediments and Quaternary loess, which obscure details of the lithospheric structure. This study describes a new 310 km-long deep seismic reflection line striking NE-SW across the interior of NE Tibet. Integrating its data with a previously described 165 km-long deep seismic profile of the Tibet-Ordos transition zone together, these datasets provide a complete picture of the crustal architecture of the north-easternmost Tibetan Plateau. Gravity anomaly and previous geological evidence also help constrain complex deformation pattern in the region. Interpretations of these patterns indicate the importance of the large-scale sinistral Haiyuan fault zone and inherited vertical variation in mechanical properties of the lithosphere in the overall tectonic evolution of the NE Tibetan Plateau. The overall crustal architecture obtained in this study provides spatial context for the neotectonic evolution of NE Tibet and helps constrain the interplay of geologic and geodynamic processes affecting NE Tibet and adjacent regions.

  14. A seismic reflection and GLORIA study of compressional deformation in the Gorringe Bank region, eastern North Atlantic

    Hayward, N.; Watts, A. B.; Westbrook, G. K.; Collier, J. S.


    Seismic reflection and GLORIA side-scan sonar data obtained on RRS Charles Darwin cruise CD64 reveal new information on the styles of deformation in the Gorringe Bank region, at the eastern end of the Azores-Gibraltar plate boundary. Previous studies suggest that Gorringe Bank was formed by the overthrusting of a portion of the African plate upon the Eurasian plate. The new seismic data show, however, that the most intensely deformed region is located south of Gorringe Bank, on the northern flanks of a NW-SE-trending submarine ridge which includes the Ampere and Coral Patch seamounts. The deformation is expressed as long-wavelength (up to 60 km), large-amplitude (up to 800 m) folds in the sediments and underlying acoustic basement, which in places are associated with one or more reverse faults, and as a fabric of short-wavelength folds (up to 3 km) with a NE trend. In contrast, the same sedimentary units when traced beneath the flanking plains are undeformed, except for some faults with a small throw (~30 m), some of which offset the seafloor. GLORIA data show that recent deformation is broadly distributed over the region. Structural trends rotate from 45 deg in the west to 70 deg in the east of the region, nearly perpendicular to the NW-verging plate motion vectors as determined from plate kinematic models. Flexure modelling suggests that a portion of Gorringe Bank has loaded 152 Ma oceanic lithosphere and that a maximum of 50 km of shortening has occurred at Gorringe Bank since the mid-Miocene. Our observations support a model in which there is no single plate boundary in the region, rather that the deformation is distributed over a 200-330 km wide zone.

  15. Magnetic Twist and Writhe of Active Regions: On the Origin of Deformed Flux Tubes

    Fuentes, M López; Mandrini, C H; Pevtsov, A A; van Driel-Gesztelyi, L


    We study the long term evolution of a set of 22 bipolar active regions (ARs) in which the main photospheric polarities are seen to rotate one around the other during several solar rotations. We first show that differential rotation is not at the origin of this large change in the tilt angle. A possible origin of this distortion is the nonlinear development of a kink-instability at the base of the convective zone; this would imply the formation of a non-planar flux tube which, while emerging across the photosphere, would show a rotation of its photospheric polarities as observed. A characteristic of the flux tubes deformed by this mechanism is that their magnetic twist and writhe should have the same sign. From the observed evolution of the tilt of the bipoles, we derive the sign of the writhe of the flux tube forming each AR; while we compute the sign of the twist from transverse field measurements. Comparing the handedness of the magnetic twist and writhe, we find that the presence of kink-unstable flux tube...

  16. Development of high-performance and low-noise axial-flow fan units in their local operating region

    Heo, Seung; Ha, Min Ho; Cheong, Cheol Ung [Pusan National University, Busan (Korea, Republic of); Kim, Tae Hoon [LG Electronics Inc., Changwon (Korea, Republic of)


    Aerodynamic and aeroacoustic performances of an axial-flow fan unit are improved by modifying its housing structure without changing the fan blade. The target axial-flow fan system is used to lower temperature of a compressor and a condenser in the machine room of a household refrigerator which has relatively high system resistance due to complex layout of structures inside it. First, the performance of the fan system is experimentally characterized by measuring its volume flow rate versus static pressure using a fan performance tester satisfying the AMCA (Air Movement and Control Association) regulation, AMCA 210-07. The detailed structure of flow driven by the fan is numerically investigated using a virtual fan performance tester based on computational fluid dynamics techniques. The prediction result reveals possible loss due to radial and tangential velocity components in the wake flow downstream of the fan. The length of the fan housing is chosen as a design parameter for improving the aerodynamic and aeroacoustic performances of the fan unit by reducing the identified radial and tangential velocity components. Three fan units with different housing lengths longer than the original are analyzed using the virtual fan performance tester. The results confirm the improved aerodynamic performance of the proposed three designs. The flow field driven by the proposed fan unit is closely examined to find the causes for the observed performance improvements, which ensures that the radial and tangential velocity components in the wake flow are reduced. Finally, the improved performance of the proposed fan systems is validated by comparing the P-Q and efficiency curves measured using the fan performance tester. The noise emission from the household refrigerator is also found to be lessened when the new fan units are installed.

  17. Axially deformed solution of the Skyrme-Hartree-Fock-Bogoliubov equations using the transformed harmonic oscillator basis (II) HFBTHO v2.00d: A new version of the program

    Stoitsov, M. V.; Schunck, N.; Kortelainen, M.; Michel, N.; Nam, H.; Olsen, E.; Sarich, J.; Wild, S.


    We describe the new version 2.00d of the code HFBTHO that solves the nuclear Skyrme-Hartree-Fock (HF) or Skyrme-Hartree-Fock-Bogoliubov (HFB) problem by using the cylindrical transformed deformed harmonic oscillator basis. In the new version, we have implemented the following features: (i) the modified Broyden method for non-linear problems, (ii) optional breaking of reflection symmetry, (iii) calculation of axial multipole moments, (iv) finite temperature formalism for the HFB method, (v) linear constraint method based on the approximation of the Random Phase Approximation (RPA) matrix for multi-constraint calculations, (vi) blocking of quasi-particles in the Equal Filling Approximation (EFA), (vii) framework for generalized energy density with arbitrary density-dependences, and (viii) shared memory parallelism via OpenMP pragmas. Program summaryProgram title: HFBTHO v2.00d Catalog identifier: ADUI_v2_0 Program summary URL: Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU General Public License version 3 No. of lines in distributed program, including test data, etc.: 167228 No. of bytes in distributed program, including test data, etc.: 2672156 Distribution format: tar.gz Programming language: FORTRAN-95. Computer: Intel Pentium-III, Intel Xeon, AMD-Athlon, AMD-Opteron, Cray XT5, Cray XE6. Operating system: UNIX, LINUX, WindowsXP. RAM: 200 Mwords Word size: 8 bits Classification: 17.22. Does the new version supercede the previous version?: Yes Catalog identifier of previous version: ADUI_v1_0 Journal reference of previous version: Comput. Phys. Comm. 167 (2005) 43 Nature of problem: The solution of self-consistent mean-field equations for weakly-bound paired nuclei requires a correct description of the asymptotic properties of nuclear quasi-particle wave functions. In the present implementation, this is achieved by using the single-particle wave functions

  18. Relativistic RPA in axial symmetry

    Arteaga, D Pena; 10.1103/PhysRevC.77.034317


    Covariant density functional theory, in the framework of self-consistent Relativistic Mean Field (RMF) and Relativistic Random Phase approximation (RPA), is for the first time applied to axially deformed nuclei. The fully self-consistent RMF+RRPA equations are posed for the case of axial symmetry and non-linear energy functionals, and solved with the help of a new parallel code. Formal properties of RPA theory are studied and special care is taken in order to validate the proper decoupling of spurious modes and their influence on the physical response. Sample applications to the magnetic and electric dipole transitions in $^{20}$Ne are presented and analyzed.

  19. Impact of permafrost degradation on embankment deformation of Qinghai-Tibet Highway in permafrost regions

    彭惠; 马巍; 穆彦虎; 金龙


    Based on long-term monitoring data, the relationships between permafrost degradation and embankment deformation are analyzed along the Qinghai−Tibet Highway (QTH). Due to heat absorbing effect of asphalt pavement and climate warming, permafrost beneath asphalt pavement experienced significant warming and degradation. During the monitoring period, warming amplitude of the soil at depth of 5 m under asphalt ranged from 0.21 °C at the XD1 site to 0.5 °C at the KL1 site. And at depth of 10 m, the increase amplitude of ground temperature ranged from 0.47 °C at the NA1 site to 0.07 °C at the XD1 site. Along with ground temperature increase, permafrost table beneath asphalt pavement decline considerably. Amplitude of permafrost table decline varied from 0.53 m at the KL1 site to 3.51 m at the NA1 site, with mean amplitude of 1.65 m for 8 monitoring sites during the monitoring period. Due to permafrost warming and degradation, the embankment deformation all performed as settlement at these sites. At present, those settlements still develop quickly and are expected to continue to increase in the future. The embankment deformations can be divided into homogeneous deformation and inhomogeneous deformation. Embankment longitudinal inhomogeneous deformation causes the wave deformations and has adverse effects on driving comfort and safety, while lateral inhomogeneous deformation causes longitudinal cracks and has an adverse effect on stability. Corresponding with permafrost degradation processes, embankment settlement can be divided into four stages. For QTH, embankment settlement is mainly comprised of thawing consolidation of ice-rich permafrost and creep of warming permafrost beneath permafrost table.

  20. A Contribution to Mitigating Seismic Risk in the Bay Area: The Bay Area Regional Deformation (BARD) GPS Network

    Houlie, N.; Romanowicz, B.; Hellweg, P.


    In the San Francisco Bay Area (SFBA), two million people live in a geologically complex, tectonically active region that has experienced several historic earthquakes, including the 1868 Hayward, the 1906 San Francisco, and 1989 Loma Prieta earthquakes. Geodetic measurements, which are especially useful for detecting deformation and strain on deep structures throughout the seismic cycle, show that Bay Area deformation is both spatially complex and varying with time. Increasingly, GPS data can also be used in real time to complement seismic data in providing robust real-time earthquake information, and, potentially, early warning. The Bay Area Regional Deformation (BARD) network of permanent, continuously operating Global Positioning System (GPS) receivers monitors crustal deformation in the Bay Area and northern California. BARD is a network collocated with several seismic networks (BDSN, NHFN, mini-PBO) operating in Northern California. As the local determination of magnitude is problematic for large earthquakes, the GPS will provide strong constraints on rupture geometry and amount of slip along the slipping fault. Thus, the collocation of all the networks will help mitigate earthquake- related risks associated with an earthquake in the SFBA or in northern California.

  1. StaMPS Improvement for Deformation Analysis in Mountainous Regions: Implications for the Damavand Volcano and Mosha Fault in Alborz

    Sanaz Vajedian


    Full Text Available Interferometric Synthetic Aperture Radar (InSAR capability to detect slow deformation over terrain areas is limited by temporal decorrelation, geometric decorrelation and atmospheric artefacts. Multitemporal InSAR methods such as Persistent Scatterer (PS-InSAR and Small Baseline Subset (SBAS have been developed to deal with various aspects of decorrelation and atmospheric problems affecting InSAR observations. Nevertheless, the applicability of both PS-InSAR and SBAS in mountainous regions is still challenging. Correct phase unwrapping in both methods is hampered due to geometric decorrelation in particular when using C-band SAR data for deformation analysis. In this paper, we build upon the SBAS method implemented in StaMPS software and improved the technique, here called ISBAS, to assess tectonic and volcanic deformation in the center of the Alborz Mountains in Iran using both Envisat and ALOS SAR data. We modify several aspects within the chain of the processing including: filtering prior to phase unwrapping, topographic correction within three-dimensional phase unwrapping, reducing the atmospheric noise with the help of additional GPS data, and removing the ramp caused by ionosphere turbulence and/or orbit errors to better estimate crustal deformation in this tectonically active region. Topographic correction is done within the three-dimensional unwrapping in order to improve the phase unwrapping process, which is in contrast to previous methods in which DEM error is estimated before/after phase unwrapping. Our experiments show that our improved SBAS approach is able to better characterize the tectonic and volcanic deformation in the center of the Alborz region than the classical SBAS. In particular, Damavand volcano shows an average uplift rate of about 3 mm/year in the year 2003–2010. The Mosha fault illustrates left-lateral motion that could be explained with a fault that is locked up to 17–18 km depths and slips with 2–4 mm

  2. The deformation behavior of soil mass in the subsidence region of Beijing, China

    Tian, F.; Liu, J.-R.; Luo, Y.; Zhu, L.; Yang, Y.; Zhou, Y.


    Land subsidence induced by excessive groundwater withdrawal has been a major environmental and geological problem in the Beijing plain area. The monitoring network of land subsidence in Beijing has been established since 2002 and has covered the entire plain area by the end of 2008. Based on data from extensometers and groundwater observation wells, this paper establishes curves of variations over time for both soil mass deformation and water levels and the relationship between soil mass deformation and water level. In addition, an analysis of deformation behavior is carried out for soil mass with various lithologies at different depths depending on the corresponding water level. Finally, the deformation behavior of soil mass is generalized into five categories. The conclusions include: (i) the current rate of deformation of the shallow soil mass is slowing, and most of the mid-deep and deep soil mass continue to compress at a more rapid speed; (ii) the sand strata behaves elastically, while the clay soil mass at different depths is usually characterized by elastic-plastic and creep deformation, which can be considered as visco-elastoplastic.

  3. Imaging active faulting in a region of distributed deformation from the joint clustering of focal mechanisms and hypocentres: Application to the Azores-western Mediterranean region

    Custódio, Susana; Lima, Vânia; Vales, Dina; Cesca, Simone; Carrilho, Fernando


    The matching between linear trends of hypocentres and fault planes indicated by focal mechanisms (FMs) is frequently used to infer the location and geometry of active faults. This practice works well in regions of fast lithospheric deformation, where earthquake patterns are clear and major structures accommodate the bulk of deformation, but typically fails in regions of slow and distributed deformation. We present a new joint FM and hypocentre cluster algorithm that is able to detect systematically the consistency between hypocentre lineations and FMs, even in regions of distributed deformation. We apply the method to the Azores-western Mediterranean region, with particular emphasis on western Iberia. The analysis relies on a compilation of hypocentres and FMs taken from regional and global earthquake catalogues, academic theses and technical reports, complemented by new FMs for western Iberia. The joint clustering algorithm images both well-known and new seismo-tectonic features. The Azores triple junction is characterised by FMs with vertical pressure (P) axes, in good agreement with the divergent setting, and the Iberian domain is characterised by NW-SE oriented P axes, indicating a response of the lithosphere to the ongoing oblique convergence between Nubia and Eurasia. Several earthquakes remain unclustered in the western Mediterranean domain, which may indicate a response to local stresses. The major regions of consistent faulting that we identify are the mid-Atlantic ridge, the Terceira rift, the Trans-Alboran shear zone and the north coast of Algeria. In addition, other smaller earthquake clusters present a good match between epicentre lineations and FM fault planes. These clusters may signal single active faults or wide zones of distributed but consistent faulting. Mainland Portugal is dominated by strike-slip earthquakes with fault planes coincident with the predominant NNE-SSW and WNW-ESE oriented earthquake lineations. Clusters offshore SW Iberia are

  4. Structural evolution of the Rieserferner Pluton: insight into the localization of deformation and regional tectonics implications

    Ceccato, Alberto; Pennacchioni, Giorgio


    deformation structures within the RFP is controlled by the development and later reactivation in shear of two main sets of joints during cooling and progressive exhumation of the pluton. These joints were either exploited as faults or localized ductile shear zones. In the RFP, the kinematics of shear reactivation is complex, with the same joint set recording different senses of shear and transport directions. Preliminary kinematic analysis and qualitative paleostress reconstruction show that there has been a clockwise rotation of the main regional shortening direction from WNW-ESE, during the first ductile event, to N-S during later brittle deformation. These two different shortening directions fit with those inferred, respectively, for Austroalpine nappe stacking by Ratschbacher (1989) and for the Alpine convergence during late Oligocene-Miocene within the Tauern window (Pennacchioni & Mancktelow, 2007). References Cesare, B. (1994). Hercynite as the product of staurolite decomposition in the contact aureole of Vedrette di Ries, eastern Alps, Italy. Contributions to Mineralogy and Petrology, 116(3), 239-246. Pennacchioni, G., Di Toro, G., Brack, P., Menegon, L., & Villa, I. M. (2006). Brittle-ductile-brittle deformation during cooling of tonalite (Adamello, Southern Italian Alps). Tectonophysics, 427(1), 171-197. Pennacchioni, G., & Mancktelow, N. S. (2007). Nucleation and initial growth of a shear zone network within compositionally and structurally heterogeneous granitoids under amphibolite facies conditions. Journal of Structural Geology, 29(11), 1757-1780. Ratschbacher, L., Frisch, W., Neubauer, F., Schmid, S. M., & Neugebauer, J. (1989). Extension in compressional orogenic belts: the eastern Alps. Geology, 17(5), 404-407. Romer, R. L., & Siegesmund, S. (2003). Why allanite may swindle about its true age. Contributions to Mineralogy and Petrology, 146(3), 297-307. Steenken, A., Siegesmund, S., & Heinrichs, T. (2000). The emplacement of the Rieserferner Pluton (Eastern

  5. Research on Long-term Deformation of Concrete-filled Steel Tubular Stubs with Expansive Additive Under Axial Loading%钢管微膨胀混凝土轴压短柱长期变形研究

    王玉银; 耿悦; 张素梅


    针对钢管混凝土拱桥中普遍采用的钢管微膨胀高性能混凝土,考虑轴压比、加载龄期等因素的影响,进行了圆钢管微膨胀混凝土轴心受压短柱的长期变形试验研究。采用逐步积分法,将5种不同混凝土收缩、徐变模型进行适当修正,应用于钢管微膨胀混凝土轴心受压短柱的长期变形分析,并将分析结果与试验结果进行对比。分析了含钢率、加载龄期、持荷时间、混凝土强度等因素对钢管微膨胀混凝土构件长期静力性能的影响。研究结果表明:修正后的EC2,MC90及AFREM模型在分析加载龄期不超过28d的钢管微膨胀混凝土构件在轴向荷载作用下的长期变形性能时具有较高的精度;核心混凝土时效作用对钢管微膨胀混凝土构件长期静力响应的影响显著。%Aimed at high performance concrete-filled steel tubular(CFST) with expansive additive which has been widely adopted in CFST arch bridges,considering the influence of axial compression ratio and loading age,test study of long-term deformation of circular CFST stubs with expansive additive under axial loading was carried out.Using step-by-step integration method,5 different concrete models of shrinkage and creep were modified,then modified models were applied to long-term deformation analysis of CFST stubs with expansive additive.Analysis result and test result were compared.The influences of ratio of steel area over concrete area,loading age,duration of loading,strength of the core concrete,etc.on the long-term static performance of these CFST specimens were analyzed.Results show that the modified models EC2,MC90 and AFREM can well predict the long-term deformation performance of CFST stubs with expansive additive loaded before 28 days.Time-effects of core concrete have considerable influence on the long-term static response of CFST specimens with expansive additive.


    O. A. Kuchay


    Full Text Available The inversion seismic tomography algorithm (ITS was used to calculate 3D seismic anomalies models for velocities of P- and S-waves in the zone of the Sunda arc, Indonesia. In the area under study, strong earthquakes (M>4.8 are clustered in the zone of high P-wave velocities. Earthquake hypocenters are located in zones of both high and low velocity anomalies of S-waves. The giant Sumatra earthquake (December 26, 2004, Mw=9.0 ruptured the greatest fault length of any recorded earthquake, and the rupture started in the area wherein the sign of P-wave velo­city anomalies is abruptly changed. We calculated seismotectonic deformations (STD from data on mechanisms of 2227 earthquakes recorded from 1977 to 2013, and our calculations show that the STD component, that controls vertical extension of rocks, is most stable through all the depth levels. In the marginal regions at the western and eastern sides of the Sunda arc, the crustal areas (depths from 0 to 35 km are subject to deformations which sign is opposite to that of deformations in the central part. Besides, at depths from 70 to 150 km beneath the Sumatra earthquake epicentre area, the zone is subject to deformations which sign is opposite to that of deformations in the studied part of the Sunda arc. For earthquakes that may occur in the crust in the Sunda arc in the contact zone of the plates, maximum magnitudes depend on the direction of pressure imposed by the actively subducting plate, which is an additional criteria for determining the limit magnitude for the region under study. 

  7. Extreme deformations and clusterization at high spin in the A ~ 40 mass region

    Ray, Debisree; Afanasjev, Anatoli


    Recent revival of the interest to the study of superdeformation and clusterization in light nuclei has motivated us to undertake the study of extreme deformations in the A ~ 32 - 50 N ~ Z nuclei. Unfortunately, at spin zero the predicted structures with extreme deformation are located at high excitation energies which prevents their experimental observation. On the other hand, the rotation brings such structures closer to the yrast line and, in principle, makes their observation possible with future generation of facilities such as GRETA. Thus, the systematic study of the extremely deformed structures and clusterization has been performed in the framework of cranked relativistic mean field theory. The major features of such structures, the spins at which they become yrast and the possiblities of their experimental observation will be discussed in this presentation. This work has been supported by the U.S. Department of Energy under the Grant DE-FG02-07ER41459.

  8. Validation of the deformable image registration system elastix in the head and neck region

    Zukauskaite, R.; Brink, C.; Hansen, C. R.


    evaluates the accuracy of the open source deformable registration tool elastix when used for registration of different organ structures on planning CT and relapse CT scans of head and neck patients. Materials and Methods: Twenty patients treated with definitive IMRT for oral cavity, oropharynx...... cord, mandible, right/left parotid and submandibular glands, thyroid gland and vertebrae C3-5) on planning CT (pCT), relapse CT (rCT) and re-delineated again on the planning CT (reCT). The contouring on the relapse CT was mapped to the planning CT using elastix ( Spatial...... delineation. Significant correlations within single organs were not found. Conclusions: Deformable registration of head and neck CT images using elastix resulted in a combined delineation and deformation uncertainty of approximately twice the uncertainty related to the manual delineation performed on one CT...

  9. What drives microplate motion and deformation in the northeastern Caribbean plate boundary region?

    van Benthem, S.A.C.|info:eu-repo/dai/nl/304833657; Govers, R.|info:eu-repo/dai/nl/108173836; Wortel, R.|info:eu-repo/dai/nl/068439202


    The north Caribbean plate boundary zone is a broad deformation zone with several fault systems and tectonic blocks that move with different velocities. The indentation by the Bahamas Platform (the “Bahamas Collision”) is generally invoked as a cause of this fragmentation. We propose that a second


    V. Yu. Timofeev


    Full Text Available Tilt measurements have been taken in the underground gallery at Talaya Seismological Station for almost three decades, from March 1985 till 2014. Based on such data, deformation curves were constructed and analysed in the frame of elastic and viscous-elastic models of the geological medium. From estimated annual deformation rates, it became possible to reveal deformation cycles ranging from 3 to 18 years with amplitudes up to 5 arc-seconds (2·10–5. For the bedrock in the Talaya stream valley, the elastic modulus was estimated at 20 GPa. In frame of the Kelvin viscoelastic model, the apparent viscosity of the medium was estimated at 1019 Pa·sec by deformation delay curve for 1989–2014 epoch. Observed vertical rates were used to estimate the size of the studied area (from 0.1 km to 6.0 km. The values estimated in our experimental investigation are used in a wide range of geophysical studies: modelling tectonic, co-seismic and post-seismic processes.

  11. What drives microplate motion and deformation in the northeastern Caribbean plate boundary region?

    van Benthem, S.A.C.|info:eu-repo/dai/nl/304833657; Govers, R.|info:eu-repo/dai/nl/108173836; Wortel, R.|info:eu-repo/dai/nl/068439202


    The north Caribbean plate boundary zone is a broad deformation zone with several fault systems and tectonic blocks that move with different velocities. The indentation by the Bahamas Platform (the “Bahamas Collision”) is generally invoked as a cause of this fragmentation. We propose that a second dr

  12. Three evolutionary stages of the collision orogenic deformation in the Middle Yangtze Region

    SUN; Yan


    13]Sun Yan Sbu Liangshu, Faure, M. et al., Tectonic development of the metamorphic core complex of Wugongshan in the Northern Jiangxi Province, Jour. of Nanjing University, 1997, 33: 447-449.[14]Faure. M., Sun Yah, Shu Liangshu et al., Extensional tectonics within a subduction-type orogen, the case study of the Wugongshan dome, Tectonophysics, 1996, 263: 77- 106.[15]Shu Liangshu, Shi Yangshen, Guo Lingzhi et al., Plate Tectonic Evolution and the Kinematics of Collisional Orogeny in the Middle Jiangnan, Eastern China, Nanjing: Publishing House of Nanjing University, 1995, 14-149.[16]Sun Yan, Shi Zejin Study on mechanical parameters of rocks and regional layerslip system in Hunan-Jiangxi area, Science in China, Ser. B. 1993, 36(8): 962-975.[17]Xu Zhiqin, Chui Junwen, Tectonic Dynamics of the Continental China, Beijing: Metallurgical Industry Publishing House, 1996, 89-178.[18]Sun Yan, Tectonics and mineralization of Lachlan Fold Belt, Canberra, Geol. Soc. of Australia, 1991, 29: 52-53.[19]Faure, M., The geodynamic evolution of the Eastern Eurasian margin in Mesozoic times, Tectonophysics, 1992, 208: 97-411.[20]Herwegh, M., Handy, M. R., Heilbronner, R., Evolution of mylonitic microfabric (EMM), a computer application for educational purposes, Tectonophysics, 1999, 303: 141-146.21.Wiens, D. A., Sliding skis and slipping faults, Nature, 1998, 279: 824-825.[21]Sun Yan, Suzuki, T., Study on the ductile deformation domain of the simple shear in rocks, Science in China, Ser. B, 1992,35(12): 1512-1520.[22]Molnar, P., Tapponnier, P., Cenozoic tectonics of Asia: effects of a continental collision, Science, 1975, 189: 419-426.[23]Buke, K.. Sengor, A. B. C., Tectonic escape in evolution of the continenental crust, in Reflection Seismology, The Continental Crust, Geodynamics Series (14). (eds. Barazangi, M., Brown, L.), Washington D.C.: American Geophysical Union,1986. 41 -53.[24]Shan Yanjun, Xia Bangdong, A preliminary discussion on

  13. Application of Persistent Scatterers deformation inventories to assess regional landslide susceptibility

    Oliveira, S. C.; Nico, G.; Zêzere, J. L.; Catalão, J.; Garcia, R. A. C.; Benevides, P.; Piedade, A.


    The consistency of landslide inventories is an important issue when analyzing a hazard scenario. Landslide Inventory maps depends on the scope, the available resources, and the scale of investigation, and are conditioned by factors such as the chosen data acquisition technique (e.g. field survey or aerial photo-interpretation), the experience of the geomorphologist, and the complexity of the study area (Guzzetti et al. 2000). In addition, the time available to complete the landslide inventory may be a constrain regarding its reliability. It is now generally accepted that landslide inventories must be permanently up to date. However, it is not easy to guarantee the complete update as well as the robustness of landslide inventories for large areas, because of the time consuming process of landslide data acquisition. In this context, Interferometric Synthetic Aperture Radar (InSAR) methods can provide data to turn more reliable the existent landslide inventories and consequently improve landslide susceptibility assessment at the regional/basin scales. The aim of this work is: i) to evaluate the possibility to use Interferometric Synthetic Aperture Radar data to generate landslide inventories; ii) to assess landslide susceptibility at a regional/basin scale with Persistent Scatterers-based landslide inventories; and iii) to validate the reliability of this landslide susceptibility map with an independent filed survey-based landslide inventory. A dataset of 58 ERS-1/2 SAR images, from 1992 to 1998, and a second dataset of 25 ENVISAT/ASAR images, from 2003 to 2009, were processed. The Persistent Scatters (PS) technique was used to estimate the Line Of Sight (LOS) surface deformation. All PSs located on a slope and with a positive LOS velocity (subsidence) are believed to be indicative of landslide activity. The main assumption after images processing and verification (validation) is that the resultant PS data-base corresponds to landslide activity, so, each PS is assumed

  14. Dynamic response of the occipito-atlanto-axial (C0-C1-C2) complex in right axial rotation.

    Chang, H; Gilbertson, L G; Goel, V K; Winterbottom, J M; Clark, C R; Patwardhan, A


    The torque-angular deformation in right axial rotation until failure of the ligamentous occipito-atlanto-axial complex subjected to variable loading rate (dynamic) axial torque was characterized using a biaxial MTS system. A special fixture and gear box that permitted right axial rotation of the specimen until failure without imposing any additional constraints were used to obtain the data. The specimens were divided into three groups and tested until failure at three different dynamic loading rates: 50, 100, and 400 degrees/s. A previous study by the authors provided data for quasi-static (4 degrees/s) loading conditions. The torque versus rotation curves can be divided into two straight regions and two transition zones. The plots clearly indicated that at loading rates higher than 4 degrees/s, the specimens became stiffer in the region of steadily increasing resistance prior to failure. The increase in stiffness was maximum at 100 degrees/s. The stiffness decreased somewhat at 400 degrees/s in comparison with 100 degrees/s, but this decrease was not significant. The resulting torque-right axial rotation curves were also examined to estimate the magnitude of maximum resistance (torque) and the corresponding angular rotation value. The average maximum resistance torque increased from 13.6 Nm at 4 degrees/s to 27.8 Nm at 100 degrees/s. The corresponding right angular rotation data (65-78 degrees), however, did not show any significant variation with loading rate. Posttest dissection of the specimens indicated that the type of injury observed was related to the rate of axial loading imposed on a specimen during testing.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. From superdeformation to extreme deformation and clusterization in the N~Z nuclei of the A~40 mass region

    Ray, D


    A systematic search for extremely deformed structures in the N~Z nuclei of the A~40 mass region has been performed for the first time in the framework of covariant density functional theory. At spin zero such structures are located at high excitation energies which prevents their experimental observation. The rotation acts as a tool to bring these exotic shapes to the yrast line or its vicinity so that their observation could become possible with future generation of $\\gamma-$tracking (or similar) detectors such as GRETA and AGATA. The major physical observables of such structures (such as transition quadrupole moments as well as kinematic and dynamic moments of inertia), the underlying single-particle structure and the spins at which they become yrast or near yrast are defined. The search for the fingerprints of clusterization and molecular structures is performed and the configurations with such features are discussed. The best candidates for observation of extremely deformed structures are identified. For ...

  16. Analysis of permanent deformations of railway embankments under repeated vehicle loadings in permafrost regions

    Wei Ma; Tuo Chen


    By large-scale dynamic tests carried out on a traditional sand-gravel embankment at the Beilu River section along the Qinghai-Tibet Railroad, we collected the acceleration waveforms close to the railway tracks when trains passed. The dynamic train loading was converted into an equivalent creep stress, using an equivalent static force method. Also, the creep equation of frozen soil was introduced according to the results of frozen soil rheological triaxial tests. A coupled creep model based on a time-hardening power function rule and the Druker-Prager yield and failure criterion was estab-lished to analyze the creep effects of a plain fill embankment under repeated train loads. The temperature field of the embankment in the permafrost area was set at the current geothermal conditions. As a result, the permanent deformation of the embankment under train loading was obtained, and the permanent deformation under the train loads to the total em-bankment deformation was also analyzed.

  17. Evolution of the lithosphere-asthenosphere system in the Carpathian-Pannonian region following the Miocene extension: as viewed in petrology, geochemistry, deformation pattern of mantle xenoliths and geophysical observations

    Kovács, István; Falus, György; Szabó, Csaba; Pintér, Zsanett; Hegedűs, Endre; Mihály, Judith; Németh, Csaba; Liptai, Nóra; Patkó, Levente; Tommasi, Andrea; Barou, Fabrice; Zajacz, Zoltán; Tribus, Martina; Konzett, Jürgen; Stalder, Roland


    Detailed geochemical and deformation analysis of numerous of mantle xenoliths from the Carpathian-Pannonian region revealed that the present lithosphere, which suffered significant thinning in the Miocene, may be divided into two major layers based on the equilibrium temperatures as indicators for the depth of origin. The shallower layer, from the MOHO to ~40 km depth, is characterized mostly by fine grained, equigranular to porphyroclastic xenoliths, generally displays an 'axial [010]' deformation pattern typical for transpressional deformation regime. Mineral constituents from this shallower layer show high Mg#, low H2O content in nominally anhydrous minerals (NAMs) and depleted in basaltic major elements implying that this layer may have undergone considerable depletion. Trace element patterns, however, show enrichment most probably due to subsequent metasomatic enrichment episodes. The deeper layer is below ~40 km and above the present lithosphere-asthenosphere boundary. The xenoliths show mainly coarse grained, protogranular texture with 'A-type' deformation pattern typical for asthenospheric flow. Minerals usually have lower Mg# and richer in basaltic major elements. The NAMs from this layer show higher H2O content than those in the shallow layer. Trace element patterns, on the other hand, do not refer to later refertilization episodes by showing dominantly depleted pattern. There is also a special group of tabular equigranular xenoliths, which may represent a domain separating these shallower and deeper layers of the present day lithosphere. This group shows geochemical and deformation properties resembling more the shallower layer, however, the H2O content of NAMs is the highest among all studied samples. Xenoliths, nevertheless, displaying transitional character among these major groups also occur indicating the complex history of the upper mantle. We suggest that the deeper, more H2O rich and less-depleted layer of the present day lithosphere is a

  18. Monitoring and analysis of ground temperature and deformation within Qinghai-Tibet Highway subgrade in permafrost region

    YaHu Tian; YuPeng Shen; WenBing Yu; JianHong Fang


    In order to study the stability of the Qinghai-Tibet Highway embankment at Chumaerhe in the permafrost region of northwest China, the ground temperature and deformation at different depths were monitored under the left and right shoulders of the embankment where thermosyphons were set up only on the left shoulder. Based on the monitored data, characteristics of ground temperature and deformation of the left and right shoulders are analyzed and discussed. The results show that the start time of freezing or thawing of the seasonal active layer was about one to two months later than that of the embankment body itself. The stability of each shoulder was mainly controlled by the settlement of different soil layers, whereas frost heave of soil had scarcely any effect on the stability of the embankment. For the left shoulder, the settlement was mainly influenced by the seasonal active layer and then by the embankment body itself, due to freeze-thaw cycles which may change the soil properties; however, the permafrost layer remained fairly stable. For the right shoulder, creep of the warm permafrost layer was the main influence factor on its stability, followed by settlement of embankment body itself, and finally settlement of the seasonal active layer. Compared with the deformation of the left shoulder, the permafrost layer under the right shoulder was less stable, which indicates that the thermosyphons had a significantly positive effect on the stability of warm permafrost.

  19. Influence of deposit architecture on intrastratal deformation, slope deposits of the Tres Pasos Formation, Chile

    Auchter, Neal C.; Romans, Brian W.; Hubbard, Stephen M.


    Slope sediments on passive and active margins deform and fail across a broad range of scales ranging from loading and sediment remobilization near the sediment-water interface to submarine landslides and mass movements that incorporate significant volumes of slope deposits. Deformational styles are characterized by updip extension and downdip compressional features that occur above a detachment surface. Conditions for failure and deformation include the presence of weak layer(s) that serve as a detachment surface, competency contrasts that allow for detachment and downslope movement, deformation above a detachment surface, and a triggering mechanism(s) that initiates failure. Slope failure processes and products are well documented at scales resolvable by seismic-reflection surveys and in instances of extensive downslope failure, but the processes and products associated with intermediate-scale slope deformation are poorly understood. Intrastratal deformation is defined as stratigraphically isolated zones of deformation bounded above and below by concordant and undeformed strata. In this study, outcrop examples of intrastratal deformation from the Upper Cretaceous Tres Pasos Formation are used to elucidate the influence of depositional architecture on slope deformation. The facies distribution associated with compensational stacking of lobe deposits is shown to have a first-order control on the location and style of deformation. Detachment planes that form in mudstone deposits associated with lobe fringe and interlobe deposits are spatially limited and deformation is restricted to interbedded sandstone and mudstone associated with off-axial lobe positions. Downslope translation was arrested by stratigraphic buttresses associated with more sandstone-prone axial deposits. Emplacement of a regionally extensive mass transport deposit is interpreted as the triggering mechanism for contemporaneous intrastratal deformation of > 60 m of underlying stratigraphy. A vertical

  20. A system for automated monitoring of embankment deformation along the Qinghai-Tibet Railway in permafrost regions

    YongPeng Yang; YaoHui Qu; HanCheng Cai; Jia Cheng; CaiMei Tang


    At present, the monitoring of embankment deformation in permafrost regions along the Qinghai-Tibet Railway is mainly done manually. However, the harsh climate on the plateau affects the results greatly by lowering the observation frequency, so the manual monitoring can barely meet the observational demand. This research develops a system of automated monitoring of embankment deformation, and aims to address the problems caused by the plateau climate and the perma-frost conditions in the region. The equipment consists of a monitoring module, a data collection module, a transmission module, and a data processing module. The field experiments during this program indicate that (1) the combined auto-mated monitoring device overcame the problems associated with the complicated and tough plateau environment by means of wireless transmission and automatic analysis of the embankment settlement data;(2) the calibration of the combined settlement gauge at −20 °C was highly accurate, with an error rate always <0.5%; (3) the gauge calibration at high-temperature conditions was also highly accurate, with an error rate<0.5%even though the surface of the instrument reached more than 50 °C;and (4) compared with the data manually taken, the data automatically acquired during field monitoring experiments demonstrated that the combined settlement gauge and the automated monitoring system could meet the requirements of the monitoring mission in permafrost regions along the Qinghai-Tibet Railway.

  1. Geodetic networks in Al-Hoceima, Fez-Meknes and Ouarzazate regions (Morocco) to monitor local deformations

    Gil, A. J.; Ruiz, A. M.; Lacy, M. C.; Galindo-Zaldívar, J.; Anahnah, F.; Ruano, P.; Álvarez-Lobato, P. Ayarza, F.; Arboleya, A. Teixel, M. L.; Azzouz, O.; Ahmamou, A. Chalouan, M.; Kchikach, A.


    In the framework of some interdisciplinary research projects, several geodetic studies have been initiated aiming to quantify ground deformation in some areas of Morocco: the Al-Hoceima region (Rif cordillera), the Fez-Meknes region and the Ouarzazate region (Atlas Mountains). The Al-Hoceima region, located in the central part of the Rif Cordilleras, has undergone an intense seismic activity, in which the most significant events occurred in 1994 and 2004 (M= 6.3). Although seismicity data support the presence of transcurrent faults, and available radar interferometry researches evidence surface deformations, geological data suggest that main seismogentic fault zone has not a surface expression. Anyway, a set of N-S oriented normal faults (Rouadi, Al-Hoceima, Trougout) determines the present-day geomorphology and seems to continue to be active in surface. In this area, a new non-permanent GPS network consisting of 6 sites has been installed and surveyed in June 2007 and September 2008. The repeated measurements of this network may allow to exactly determine the surface expression of deep tectonic deformations in this region, and to quantify the creep and the coseismic motions in the area, that will contribute to better understand the seismic hazard. The Prerif Ridges located in the Fez-Meknes region, constitute the active mountain front of the Rif cordillera that accommodates most of the recent convergence between Eurasia and African plates. South of the ridges, the Saïss foreland basin overlies the foreland rocks corresponding to the Middle Atlas. There are evidences of Quaternary uplift of the Prerif Ridges and deformation of recent sediments as consequence of the southwards propagation of reverse faults along the mountain front. In addition, the foreland basin undergoes a roughly N-S extensional regime. The region undergoes a moderate seismic activity, with catastrophic events like that occurred in 1755 which damaged Fez and Meknes. On September 2007, a non

  2. Global and Regional Axial Ocean Angular Momentum Signals and Length-of-day Variations (1985-1996)

    Ponte, Rui M.; Stammer, Detlef


    Changes in ocean angular momentum M about the polar axis are related to fluctuations in zonal currents (relative component M(sub tau) and latitudinal shifts in mass (planetary component M(sub Omega). Output from a 1 deg. ocean model is used to calculate global M(sub tau), (sub Omega), and M time series at 5 day intervals for the period January 1985 to April 1996. The annual cycle in M(sub tau), M(sub Omega), and M is larger than the semiannual cycle, and M(sub Omega) amplitudes are nearly twice those of M(sub tau). Year-to-year modulation of the seasonal cycle is present, but interannual variability is weak. The spectrum of M is red (background slope between omega(sup -1) and omega(sup -2) at sub-seasonal periods, implying a white or blue spectrum for the external torque on the ocean. Comparisons with previous studies indicate the importance of direct atmospheric forcing in inducing sub-seasonal M signals, relative to instabilities and other internal sources of rapid oceanic signals. Regional angular momentum estimates show that seasonal variability tends to be larger at low latitudes, but many local maxima exist because of the spatial structure of zonal current and mass variability. At seasonal timescales, latitudes approx. 20 deg. S - 10 deg. N contribute substantial variability to M(sub Omega), while signals in M(sub tau) can be traced to Antarctic Circumpolar Current transports and associated circulation. Variability in M is found to be small when compared with similar time series for the atmosphere and the solid Earth, but ocean signals are significantly coherent with atmosphere-solid Earth residuals, implying a measurable oceanic impact on length-of-day variations.

  3. Effect of austenite deformation in non-recrystallization region on microstructure development in low-silicon content TRIP-assisted steels

    Hosseini, Seyed Mohammad Kazem, E-mail: [Department of Materials Engineering, Imam Khomeini International University, Qazvin, P.O. Box: 34149-16818 (Iran, Islamic Republic of); Zaeri-Hanzaki, Abbass, E-mail: [School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran, P.O. Box: 14395-731 (Iran, Islamic Republic of); Yue, Steve, E-mail: [Department of Mining, and Materials Engineering, McGill University, University St., Montreal, QC, Canada H3A 2A7 (Canada)


    The influence of austenite deformation in non-recrystallization region on microstructural development in low-silicon content TRIP-assisted steels was investigated. Laboratory simulation of a typical thermomechanical control processing was carried out in an automated hot-compression testing machine. Specimens subjected to a typical multi-stage isothermal deformation/cooling program were deformed to true strains of 0, −0.15, −0.25 and −0.35 at various temperatures in austenite non-recrystallization region. Mössbauer spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM) and a novel tint-etching method were used to investigate the microstructure of deformed specimens. The results indicated that the maximum volume fraction (V{sub RA}) and carbon content (C{sub RA}%) of retained austenite can be obtained by deforming samples to some intermediate strains (ε=−0.15 for V{sub RA} and ε=−0.25 for C{sub RA}%). However, further straining of samples to ε=−0.35 resulted in a drastic reduction of both parameters due to formation of pearlite. It was found that a decrease in deformation temperature resulted in increasing V{sub RA} and C{sub RA}%. Moreover, deformation of austenite was associated with morphology changes in retained austenite particles from interlath film-like type in undeformed specimens to blocky and encapsulated types in the deformed specimens.

  4. System identification modeling and unstable behavior of the dynamics of flows within the tip region of an axial compressor blade passage

    Sterbentz, Dane M.; Prasai, Sujan; Hofle, Mary M.; Walters, Thomas; Lin, Feng; Li, Ji-chao; Bosworth, Ken; Schoen, Marco P.


    In recent years, the correlation coefficient of pressure data from the same blade passage in an axial compressor unit has been used to characterize the state of flow in the blade passage. In addition, the correlation coefficient has been successfully used as an indicator for active control action using air injection. In this work, the correlation coefficient approach is extended to incorporate system identification algorithms in order to extract a mathematical model of the dynamics of the flows within a blade passage. The dynamics analyzed in this research focus on the flow streams and pressure along the rotor blades as well as on the unsteady tip leakage flow from the rotor tip gaps. The system identification results are used to construct a root locus plot for different flow coefficients, starting far away from stall to near stall conditions. As the compressor moves closer to stall, the poles of the identified models move towards the imaginary axis of the complex plane, indicating an impending instability. System frequency data is captured using the proposed correlation based system identification approach. Additionally, an oscillatory tip leakage flow is observed at a flow coefficient away from stall and how this oscillation changes as the compressor approaches stall is an interesting result of this research. Comparative research is analyzed to determine why the oscillatory flow behavior occurs at a specific sensor location within the tip region of the rotor blade.

  5. Robust corrections for topographically-correlated atmospheric noise in InSAR data from large deforming regions

    Bekaert, David; Walters, Richard; Hooper, Andrew; Wright, Tim; Parker, Doug


    For Interferometric Synthetic Aperture Radar (InSAR) the atmosphere forms one of the biggest challenges when it comes to the extraction of small-magnitude long-wavelength tectonic signals. Spatio-temporal variation of water vapour, pressure and temperature in the troposphere is the main cause of these signals, introducing apparent differential path delays in interferograms of up to 15 cm. Several correction techniques have been applied in the past that rely on external data from weather models, GPS or spectrometer data, but these are typically limited by the lower spatial resolution of the auxiliary data. Alternatively, time-series InSAR techniques and filtering of the interferometric phase in space and time can be applied, but separating atmospheric delays from non-linear deformation is challenging. Another method, which can be applied to individual interferograms, is to estimate the correlation between interferometric phase and topography, either in a non-deforming area or using a frequency band insensitive to deformation. While this method can be successful for small areas, it does not account for spatial variation of atmospheric properties, which can be significant across regions larger than 100 km. While the slope relating phase and topography can be reliably estimated for subregions, the intercept cannot, as it is biased by the presence of unrelated signals. The intercept cannot however be neglected, as the mean height of each subregion typically varies, leading to a different intercept for each window. Here we present a new power-law representation of the topographically-correlated phase delay that can be applied locally and which is able to account for these spatial variations in atmospheric properties. We estimate the power-law from sounding data to fit altitudes of up to 4 km, as this includes the topography range in most regions of interest. We also constrain the power-law by specifying the height above which the relative tropospheric delays are

  6. High-Temperature Deformation Behavior of a Ti-6Al-7Nb Alloy in Dual-Phase (α + β) and Single-Phase (β) Regions

    Pilehva, F.; Zarei-Hanzaki, A.; Moemeni, S.; Khalesian, A. R.


    The present study aimed to characterizing the microstructure evolution of a Ti-6Al-7Nb biomedical type titanium alloy during hot working through hot compression tests. The hot deformation cycles were conducted under the strain rate of 0.0025, 0.025, and 0.25 s-1 in the temperature range of 850-1150 °C where both dual-phase (α + β) and single-phase (β) regions could be accessible. The flow stress behavior of the material for the entire deformation regime was interpreted via microstructural observations. The results indicated that in the single-phase β region (1050-1150 °C), the dynamically recrystallized (DRX) grains were formed at the deformed and elongated beta grain boundaries as a necklace-like structure. The variations in the dynamically recrystallized grain size were determined to follow the Zener-Hollomon relationship where DRX grain size was decreased by reducing the temperature and increasing the strain rate. The alloy deformation characteristics in α + β region were somewhat different. During deformation in the upper α + β temperature range (e.g., 1000 °C), the β phase would accommodate most of the deformation, while α regions remained undeformed. In the lower α + β temperature range (e.g., 850-950 °C), the kinking/bending of α lamellae as well as the subsequent globularization of α layers were postulated to be responsible for the observed flow softening behavior.

  7. Experimental study on the vertical deformation of aquifer soils under conditions of withdrawing and recharging of groundwater in Tongchuan region, China

    Wei, Ya-ni; Fan, Wen; Cao, Yanbo


    Land subsidence due to aquifer-system compaction accompanying groundwater extraction is a global hazard. Rising urban construction and groundwater demand necessitate increased awareness and better understanding of the geological problem. Motivated by the lack of laboratory-scale studies on this issue, an experimental investigation on the newly developed Tongchuan region, China, is presented. The study addresses the deformation behaviors of three soil samples, with the lithology of silty clay, silt, and fine sand, under the conditions of groundwater withdrawal and recharge using the GDS Consolidation Testing System. Results indicate that all three samples were characterized by elastic-plastic deformation under the conditions of withdrawing and recharging. The vertical deformation of the silty clay in the aquitard above the first confined aquifer was larger than those of the other two samples, and its deformation is a gradual and long process; thus, considerable attention should be paid to deformation in this aquitard due to the apparent creep effect and tiny rebound deformation. However, the settlement of the fine sand in the second confined aquifer cannot be ignored due to the great thickness of the aquifer. For the same soil, as the pore-water pressure declined, the unit rate of vertical deformation decreased gradually, whereas the creep effect of deformation in the later declining stage of pore-water pressure was more apparent than that in the former declining stage. These observations are highly important to the local government, which is developing measures to prevent and control subsidence.

  8. Light axial vector mesons

    Chen, Kan; Liu, Xiang; Matsuki, Takayuki


    Inspired by the abundant experimental observation of axial vector states, we study whether the observed axial vector states can be categorized into the conventional axial vector meson family. In this paper we carry out analysis based on the mass spectra and two-body Okubo-Zweig-Iizuka-allowed decays. Besides testing the possible axial vector meson assignments, we also predict abundant information for their decays and the properties of some missing axial vector mesons, which are valuable to further experimental exploration of the observed and predicted axial vector mesons.

  9. Excavation-caused extra deformation of existing masonry residence in soft soil region

    Tang, Y.; Franceschelli, S.


    Growing need for construction of infrastructures and buildings in fast urbanization process creates challenges of interaction between buildings under construction and adjacent existing buildings. This paper presents the mitigation of contradiction between two parties who are involved the interaction using civil engineering techniques. Through the in-depth analysis of the results of monitoring surveys and enhanced accuracy and reliability of surveys, a better understanding of the behavior of deformable buildings is achieved. Combination with the original construction documents, the two parties agree that both of them are responsible for building damages and a better understanding for the rehabilitation of the existing buildings is focused on. Two cases studies are used to demonstrate and describe the importance of better understanding of the behavior of existing buildings and their rehabilitations. The objective of this study is to insight into mechanisms of soil-structure interaction for buildings adjacent to deep excavations, which can result in a damage in existing masonry residence, and to take the optimized measures to make deep excavations safety and economic and adjacent buildings keep good serviceability in urban areas with soft soil conditions.

  10. Regional polyphase deformation of the Eastern Sierras Pampeanas (Argentina Andean foreland): strengths and weaknesses of paleostress inversion

    Traforti, Anna; Zampieri, Dario; Massironi, Matteo; Viola, Giulio; Alvarado, Patricia; Di Toro, Giulio


    The Eastern Sierras Pampeanas of central Argentina are composed of a series of basement-cored ranges, located in the Andean foreland c. 600 km east of the Andean Cordillera. Although uplift of the ranges is partly attributed to the regional Neogene evolution (Ramos et al. 2002), many questions remain as to the timing and style of deformation. In fact, the Eastern Sierras Pampeanas show compelling evidence of a long lasting brittle history (spanning the Early Carboniferous to Present time), characterised by several deformation events reflecting different tectonic regimes. Each deformation phase resulted in further strain increments accommodated by reactivation of inherited structures and rheological anisotropies (Martino 2003). In the framework of such a polyphase brittle tectonic evolution affecting highly anisotropic basement rocks, the application of paleostress inversion methods, though powerful, suffers from some shortcomings, such as the likely heterogeneous character of fault slip datasets and the possible reactivation of even highly misoriented structures, and thus requires careful analysis. The challenge is to gather sufficient fault-slip data, to develop a proper understanding of the regional evolution. This is done by the identification of internally consistent fault and fracture subsets (associated to distinct stress states on the basis of their geometric and kinematic compatibility) in order to generate a chronologically-constrained evolutionary conceptual model. Based on large fault-slip datasets collected in the Sierras de Cordoba (Eastern Sierras Pampeanas), reduced stress tensors have been generated and interpreted as part of an evolutionary model by considering the obtained results against: (i) existing K-Ar illite ages of fault gouges in the study area (Bense et al. 2013), (ii) the nature and orientation of pre-existing anisotropies and (iii) the present-day stress field due to the convergence of the Nazca and South America plates (main shortening

  11. Deformation Rates in the Snake River Plain and Adjacent Basin and Range Regions Based on GPS Measurements

    Payne, S. J.; McCaffrey, R.; King, R. W.; Kattenhorn, S. A.


    We estimate horizontal velocities for 405 sites using Global Positioning System (GPS) phase data collected from 1994 to 2010 within the Northern Basin and Range Province, U.S.A. The velocities reveal a slowly-deforming region within the Snake River Plain in Idaho and Owyhee-Oregon Plateau in Oregon separated from the actively extending adjacent Basin and Range regions by shear. Our results show a NE-oriented extensional strain rate of 5.6 ± 0.7 nanostrain/yr in the Centennial Tectonic Belt and an ~E-oriented extensional strain rate of 3.5 ± 0.2 nanostrain/yr in the Great Basin. These extensional rates contrast with the very low strain rate within the 125 km x 650 km region of the Snake River Plain and Owyhee-Oregon Plateau which is not distinguishable from zero (-0.1 ± 0.4 x nanostrain/yr). Inversions of Snake River Plain velocities with dike-opening models indicate that rapid extension by dike intrusion in volcanic rift zones, as previously hypothesized, is not currently occurring. GPS data also disclose that rapid extension in the surrounding regions adjacent to the slowly-deforming region of the Snake River Plain drives shear between them. We estimate right-lateral shear with slip rates of 0.3-1.5 mm/yr along the northwestern boundary adjacent to the Centennial Tectonic Belt and left-lateral oblique extension with slip rates of 0.5-1.5 mm/yr along the southeastern boundary adjacent to the Intermountain Seismic Belt. The fastest lateral shearing evident in the GPS occurs near the Yellowstone Plateau where earthquakes with right-lateral strike-slip focal mechanisms are within a NE-trending zone of seismicity. The regional velocity gradients are best fit by nearby poles of rotation for the Centennial Tectonic Belt, Snake River Plain, Owyhee-Oregon Plateau, and eastern Oregon, indicating that clockwise rotation is not locally driven by Yellowstone hotspot volcanism, but instead by extension to the south across the Wasatch fault possibly due to gravitational

  12. Regional Longitudinal Myocardial Deformation Provides Incremental Prognostic Information in Patients with ST-Segment Elevation Myocardial Infarction

    Biering-Sørensen, Tor; Jensen, Jan Skov; Pedersen, Sune H;


    BACKGROUND: Global longitudinal systolic strain (GLS) has recently been demonstrated to be a superior prognosticator to conventional echocardiographic measures in patients after myocardial infarction (MI). The aim of this study was to evaluate the prognostic value of regional longitudinal...... myocardial deformation in comparison to GLS, conventional echocardiography and clinical information. METHOD: In total 391 patients were admitted with ST-Segment elevation myocardial infarction (STEMI), treated with primary percutaneous coronary intervention and subsequently examined by echocardiography. All...... patients were examined by tissue Doppler imaging (TDI) and two-dimensional strain echocardiography (2DSE). RESULTS: During a median-follow-up of 5.3 (IQR 2.5-6.1) years the primary endpoint (death, heart failure or a new MI) was reached by 145 (38.9%) patients. After adjustment for significant confounders...

  13. Complex deformation in the Caucasus region revealed by ambient noise seismic tomography

    Legendre, Cédric P.; Tseng, Tai-Lin; Chen, Ying-Nien; Huang, Tzu-Ying; Gung, Yuan-Cheng; Karakhanyan, Arkadiy; Huang, Bor-Shouh


    Cross-correlation of 3years of ambient seismic noise recorded at 35 seismic stations deployed in Caucasus region yields hundreds of short-period surface-wave phase-speed dispersion curves on inter-station paths. We inverted these measurements using two techniques to construct tomographic images of the principal geological units of Caucasus. High-resolution isotropic and azimuthally anisotropic phase-velocity maps (at periods between 5 and 20s) and shear-velocity tomographic maps between 5 and 30km are generated. The resulting maps show a velocity dichotomy between the Caucasus region and the surrounding that is interpreted in term of changes in crustal thickness. There is also a strong dichotomy in the anisotropic pattern between the eastern part and the western part of the Caucasus. This difference in both amplitudes and directions of the 2ψ anisotropy is linked to the tectonic regime changes in the region. These observations suggest a good correlation between the tomographic models and the geology of the region. It was also possible to identify the early stage of the indentation of the Arabian Plate into the Eurasian plate, as well as to detect the possible magma chamber responsible for the Javakheti highland.

  14. A review about the mechanisms associated with active deformation, regional uplift and subsidence in southern South America

    Folguera, Andrés; Gianni, Guido; Sagripanti, Lucía; Rojas Vera, Emilio; Novara, Iván; Colavitto, Bruno; Alvarez, Orlando; Orts, Darío; Tobal, Jonathan; Giménez, Mario; Introcaso, Antonio; Ruiz, Francisco; Martínez, Patricia; Ramos, Victor A.


    A broad range of processes acted simultaneously during the Quaternary producing relief in the Andes and adjacent foreland, from the Chilean coast, where the Pacific Ocean floor is being subducted beneath South American, to the Brazilian and the Argentinean Atlantic platform area. This picture shows to be complex and responds to a variety of processes. The Geoid exemplifies this spectrum of uplift mechanisms, since it reflects an important change at 35°S along the Andes and the foreland that could be indicating the presence of dynamic forces modeling the topography with varying intensity through the subduction margin. On the other hand, mountains uplifted in the Atlantic margin, along a vast sector of the Brazilian Atlantic coast and inland regions seem to be created at the area where the passive margin has been hyper-extended and consequently mechanically debilitated and the forearc region shifts eastwardly at a similar rate than the westward advancing continent. Therefore the forearc at the Arica latitudes can be considered as relatively stationary and dynamically sustained by a perpendicular-to-the-margin asthenospheric flow that inhibits trench roll back, determining a highly active orogenic setting at the eastern Andes in the Subandean region. To the south, the Pampean flat subduction zone creates particular conditions for deformation and rapid propagation of the orogenic front producing a high-amplitude orogen. In the southern Central and Patagonian Andes, mountain (orogenic) building processes are attenuated, becoming dominant other mechanisms of exhumation such as the i) impact of mantle plumes originated in the 660 km mantle transition, ii) the ice-masse retreat from the Andes after the Pleistocene producing an isostatic rebound, iii) the dynamic topography associated with the opening of an asthenospheric window during the subduction of the Chile ridge and slab tearing processes, iv) the subduction of oceanic swells linked to transform zones and v) the

  15. Evidence for fast seismic lid structure beneath the Californian margin and its implication on regional plate deformation

    Lai, V. H.; Graves, R. W.; Wei, S.; Helmberger, D. V.


    The lithospheric structure of the Pacific and North American plates play an important role in modulating plate deformation along the California margin. Pure path models indicate that the Pacific plate has a fast thick (80km) lid overlaying a strong low velocity zone (LVZ) extending to beyond 300 km depth. In contrast, the North America structure is characterized by a relatively thin (25-35km) lid and a shallow LVZ. Vertical ray paths have similar travel times across the plate boundary for the two models, making resolution of the transitional structure difficult. Earthquakes such as the 2014 March 10 Mw 6.8 Mendocino and 2014 August 25 Mw 6.0 Napa events recorded at regional distances across California provide an opportunity to study horizontal paths and track the lateral variation in the lower crust-uppermost mantle structure under the Californian margin. Observations from both Napa and Mendocino events show direct SH-wave arrivals at Southern California Seismic Network (SCSN) stations are systematically earlier (up to 10 s) for coastal and island stations relative to inland sites. The shift in SH arrival times may be due to features such as varying crustal thickness, varying upper mantle velocity and the presence of a fast seismic lid. To test the different hypotheses, we perform extensive forward modeling using both 1-D frequency-wavenumber and 3-D finite-difference approaches. The model that best fits the SH arrival times has a fast lid (Vs = 4.7 km/s) underlying the whole California margin, with the lid increasing in thickness from east to west to a maximum thickness about 70 km in the western offshore region. The fast, thick seismic lid lends strength and rigidity to the Pacific plate lithosphere in contrast with the weaker North American continental plate, which influences the overall plate deformation along the Californian margin and is in agreement with GPS measurements.

  16. Deformation of the late Miocene to Pliocene Inyo Surface, eastern Sierra region, California

    Jayko, A.S.


    A middle and late Miocene erosion surface, the Inyo Surface, underlies late Miocene mafic flows in the White Mountains and late Miocene and (or) early Pliocene flows elsewhere in the eastern Sierra region. The Inyo Surface is correlated with an erosion surface that underlies late Miocene mafic flows in the central and northern Sierra Nevada. The mafic flows had outpourings similar to flood basalts, although of smaller volume, providing paleohorizontal and paleolowland indicators. The flows filed and locally topped the existing landscape forming broad plateau-like flats. Topographic relief in the region was characterized by weathered and rounded slopesp rior to late Miocene mafic magmatism. Relicts of the older landscape lie adjacent to late Miocene and early Pliocene basalt-covered lowlands that now occur within the crests of ranges that have 2500-3000 m relief and dramatically steep escarpments. Late Miocene mafic flows that lie on the crest of the Sierra Nevada adjacent to the White Mountains predate significant activity on the Sierra Nevada frontal fault zone. These deposits and accompanying erosion surfaces provide excellent strain markers for reconstructing part of the Walker Lane north of the Garlock fault and west of the Amargosa drainage, here referred to as the eastern Sierra region. The Inyo Surface is a compound erosional surface that records at least four major erosion events during the Cenozoic. These four surfaces were first recognized on the Kern Plateau and named from oldest to youngest, the Summit Upland, the Subsummit Plateau, the Chagoopa Plateau, and the Canyon. The three older surfaces have also been subsequently modifi ed by Pleistocene glaciation. The compound erosion surface, which is locally overlain by late Miocene mafic flows in the northern and central Sierra Nevada, is here referred to as the Lindgren Surface. Correlatives in the eastern Sierra region are found in the White Mountains, Inyo Mountains, Darwin Plateau, Coso Range, and

  17. Inferences of Integrated Lithospheric Strength from Plate-Scale Analyses of Deformation Observed in the Aegean-Anatolian Region and the Indian Ocean

    Houseman, Gregory


    In the context of a comprehensive review of the rheology and strength of the lithosphere (Marine and Petroleum Geology, 2011, doi:10.1016/j.marpetgeo.2011.05.008), Evgene Burov described the difficulty of extrapolating rock deformation laws derived from laboratory experiments to the time and length scales that apply when the Earth's lithosphere is deformed. Not only does the extrapolation introduce a large uncertainty, but even the relative importance of different possible mechanisms of deformation may be uncertain. Even though lithospheric deformation has a strong conceptual and theoretical basis, it is therefore essential, as Burov argued, that deformation laws for the lithosphere must be calibrated by using observations of deformation that occurs on a lithospheric length scale and at geological strain rates. The influence of regionally varying factors like crustal thickness, geothermal gradient and tectonic environment may induce large variations in how rapidly the lithosphere may deform in response to an applied load, not least in the contrast from continent to ocean. Plates may be deformed by different loading mechanisms but, when deformation is distributed over a broad region, the strain-rate field may be approximately constant with depth and we may integrate the in-plane stress components across the thickness of the lithosphere to derive a depth-averaged constitutive law for the deformation. This approximation is the basis for the thin viscous sheet formulation of lithospheric deformation and, in combination with appropriate observations, it allows us to calibrate the integrated resistance to processes like regional extension or convergence. In this talk I will summarise what we learn about effective lithospheric rheology from two recent studies of the distribution and rates of diffuse deformation of the lithosphere in, firstly the Anatolian-Aegean region, and secondly the Central Indian Ocean. In the first case the distribution of deformation is consistent

  18. Open source deformable image registration system for treatment planning and recurrence CT scans : Validation in the head and neck region.

    Zukauskaite, Ruta; Brink, Carsten; Hansen, Christian Rønn; Bertelsen, Anders; Johansen, Jørgen; Grau, Cai; Eriksen, Jesper Grau


    Clinical application of deformable registration (DIR) of medical images remains limited due to sparse validation of DIR methods in specific situations, e. g. in case of cancer recurrences. In this study the accuracy of DIR for registration of planning CT (pCT) and recurrence CT (rCT) images of head and neck squamous cell carcinoma (HNSCC) patients was evaluated. Twenty patients treated with definitive IMRT for HNSCC in 2010-2012 were included. For each patient, a pCT and an rCT scan were used. Median interval between the scans was 8.5 months. One observer manually contoured eight anatomical regions-of-interest (ROI) twice on pCT and once on rCT. pCT and rCT images were deformably registered using the open source software elastix. Mean surface distance (MSD) and Dice similarity coefficient (DSC) between contours were used for validation of DIR. A measure for delineation uncertainty was estimated by assessing MSD from the re-delineations of the same ROI on pCT. DIR and manual contouring uncertainties were correlated with tissue volume and rigidity. MSD varied 1-3 mm for different ROIs for DIR and 1-1.5 mm for re-delineated ROIs performed on pCT. DSC for DIR varied between 0.58 and 0.79 for soft tissues and was 0.79 or higher for bony structures, and correlated with the volumes of ROIs (r = 0.5, p elastix in HNSCC on planning and recurrence CT scans is feasible; an uncertainty of the method is close to the voxel size length of the planning CT images.

  19. The interpretation of crustal dynamics data in terms of plate motions and regional deformation near plate boundaries

    Solomon, Sean C.

    During our participation in the NASA Crustal Dynamics Project under NASA contract NAS-27339 and grant NAG5-814 for the period 1982-1991, we published or submitted for publication 30 research papers and 52 abstracts of presentations at scientific meetings. In addition, five M.I.T. Ph.D. students (Eric Bergman, Steven Bratt, Dan Davis, Jeanne Sauber, Anne Sheehan) were supported wholly or in part by this project during their thesis research. Highlights of our research progress during this period include the following: application of geodetic data to determine rates of strain in the Mojave block and in central California and to clarify the relation of such strain to the San Andreas fault and Pacific-North American plate motions; application of geodetic data to infer post seismic deformation associated with large earthquakes in the Imperial Valley, Hebgen Lake, Argentina, and Chile; determination of the state of stress in oceanic lithosphere from a systematic study of the centroid depths and source mechanisms of oceanic intraplate earthquakes; development of models for the state of stress in young oceanic regions arising from the differential cooling of the lithosphere; determination of the depth extent and rupture characteristics of oceanic transform earthquakes; improved determination of earthquake slip vectors in the Gulf of California, an important data set for the estimation of Pacific-North American plate motions; development of models for the state of stress and mechanics of fold-and-thrust belts and accretionary wedges; development of procedures to invert geoid height, residual bathymetry, and differential body wave travel time residuals for lateral variations in the characteristic temperature and bulk composition of the oceanic upper mantle; and initial GPS measurements of crustal deformation associated with the Imperial-Cerro Prieto fault system in southern California and northern Mexico. Full descriptions of the research conducted on these topics may be

  20. On the Role of Arctic Sea Ice Deformations: An Evaluation of the Regional Arctic System Model Results with Observations.

    Osinski, Robert; Maslowski, Wieslaw; Roberts, Andrew


    The atmosphere - sea ice - ocean fluxes and their contribution to rapid changes in the Arctic system are not well understood and generally are not resolved by global climate models (GCMs). While many significant model refinements have been made in the recent past, including the representation of sea ice rheology, surface albedo and ice-albedo feedback, other processes such as sea ice deformations, still require further studies and model advancements. Of particular potential interest here are linear kinematic features (LKFs), which control winter air-sea heat exchange and affect buoyancy forces in the ocean. Their importance in Arctic climate change, especially under an increasing first-year ice cover, is yet to be determined and their simulation requires representation of processes currently at sub-grid scale of most GCMs. To address some of the GCM limitations and to better understand the role of LKFs in air-sea exchange we use the Regional Arctic System Model (RASM), which allows high spatio-temporal resolution and regional focus on the Arctic. RASM is a fully coupled regional climate model, developed to study dynamic and thermodynamic processes and their coupling across the atmosphere-sea ice-ocean interface. It consists of the Weather Research and Forecasting (WRF) atmospheric model, the Parallel Ocean Program (POP), the Community Ice Model (CICE) and the Variable Infiltration Capacity (VIC) land hydrology model. The sea ice component has been upgraded to the Los Alamos Community Ice Model version 5.1 (CICE5.1), which allows either Elastic-Viscous-Plastic (EVP) or a new anisotropic (EPA) rheology. RASM's domain is pan-Arctic, with the ocean and sea ice components configured at an eddy-permitting horizontal resolution of 1/12-degree as well as 1/48-degree, for limited simulations. The atmosphere and land model components are configured at 50-km grids. All the components are coupled at a 20-minute time step. Results from multiple RASM simulations are analyzed and

  1. Nitinol stent design - understanding axial buckling.

    McGrath, D J; O'Brien, B; Bruzzi, M; McHugh, P E


    Nitinol׳s superelastic properties permit self-expanding stents to be crimped without plastic deformation, but its nonlinear properties can contribute towards stent buckling. This study investigates the axial buckling of a prototype tracheobronchial nitinol stent design during crimping, with the objective of eliminating buckling from the design. To capture the stent buckling mechanism a computational model of a radial force test is simulated, where small geometric defects are introduced to remove symmetry and allow buckling to occur. With the buckling mechanism ascertained, a sensitivity study is carried out to examine the effect that the transitional plateau region of the nitinol loading curve has on stent stability. Results of this analysis are then used to redesign the stent and remove buckling. It is found that the transitional plateau region can have a significant effect on the stability of a stent during crimping, and by reducing the amount of transitional material within the stent hinges during loading the stability of a nitinol stent can be increased.

  2. X-ray screening of the artificially deformed skulls from the Middle Bronze Age of the Low Volga region (paleopathology aspect

    Pererva Evgenii Vladimirovich


    Full Text Available The impact of the deforming structure on the human skull is one of the most challenging and debated questions in modern archeology and anthropology related to artificial deformation of the skull. This is precisely why the present study attempts to study the pathological artificially deformed skulls of representatives of the Catacomb culture originating from burial mound in the Lower Volga region. The analysis of the bone material was carried out with the use of X-ray method of the frontal and lateral views. Thirteen radiographs of skulls with traces of deliberate artificial deformation were examined. The skull shapes, structure of the skull calvarial bones, state of the cranial sutures, signs of intracranial hypertension, and symptoms of vascular and endocrine pathologies were explored and evaluated. The study discovered that Catacomb culture bearers used a variety of methods of skull deformation. Front occipital, occipital ring strain and conventional acrocephaly deformation modes were revealed. The viability and compatibility with normal human activity of artificial skull deformation was observed. In the childhood and newborn periods, individuals have applied constrictive and restrictive devices, trusses andother appliancesfor a few years, their impact couldresultin the intracranial hypertension syndrome, as well as in problems with cranial sutures obliteration. It is very much likely that the use of strain could stimulate the development of the internal frontal hyperostosis (Morgagni's disease which contributed to the emergence of endocrine abnormities in humans. The increased trauma rate of skeleton bones was observed in population of the Middle Bronze Age, as well as ear diseases which makes us once again address the issue of social and cultural phenomenon of intentional artificial deformation of the head tradition.

  3. High spin structures in the $A\\approx 40$ mass region: from superdeformation to extreme deformation and clusterization (an example of $^{28}$Si)

    Afanasjev, A V


    The search for extremely deformed structures in the yrast and near-yrast region of $^{28}$Si has been performed within the cranked relativistic mean field theory up to spin $I=20\\hbar$. The fingerprints of clusterization are seen (well pronounced) in the superdeformed (hyperdeformed) configurations.

  4. Ore body shapes versus regional deformation patterns as a base for 3D prospectivity mapping in the Skellefte Mining District, Sweden

    Bauer, T.; Skyttä, P.; Hermansson, T.; Weihed, P.


    The current work in progress is based on detailed structural analysis carried out during the last years, which unravels the crustal evolution of the ore bearing Palaeoproterozoic Skellefte District in northern Sweden. The shape and orientation of the volcanic-hosted massive sulfide (VMS) ore bodies through the district is modeled in three dimensions and reflected against the regional deformation patterns. By doing this we aim to understand the coupling between the transposition of the ore bodies and the deformation structures in the host rocks, honoring both local deformation features and regional structural transitions. The VMS ore bodies are modeled in gOcad (Paradigm) visualizing both the strike and dip of the ore lenses as well as their dimensions. 25 deposits are currently available in 3D and modelling of the remaining 55 deposits is planned or partly in progress. The ore deposits and mineralizations are classified according to their shape and size. The complexly deformed ore bodies are described each independently. Subsequently, the VMS deposits are plotted on the structural map of the Skellefte district displaying their size and strike, dip and plunge values in order to show their spatial distribution and their relationship with shear zones. The preliminary results show a good correlation between the shape and orientation of the ore bodies and the related structures. Plotting the VMS deposits on a structural map clearly demonstrates the close spatial relation of the ore deposits and regional scale shear zones. Furthermore, the deformation style within the ore deposits generally mimics the deformation style of the shear zones, e.g. the plunge of elongate ore bodies parallels the mineral lineation of the related shear zone. Based on these results, the location and shape of ore deposits may be estimated, which is an important tool for prospectivity mapping and near mine exploration of ore districts.

  5. Deformed shell model results for neutrinoless double beta decay of nuclei in A=60-90 region

    Sahu, R


    Nuclear transition matrix elements (NTME) for the neutrinoless double beta decay of $^{70}$Zn, $^{80}$Se and $^{82}$Se nuclei are calculated within the framework of the deformed shell model based on Hartree-Fock states. For $^{70}$Zn, jj44b interaction in $^{2}p_{3/2}$, $^{1}f_{5/2}$, $^{2}p_{1/2}$ and $^{1}g_{9/2}$ space with $^{56}$Ni as the core is employed. However, for $^{80}$Se and $^{82}$Se nuclei, a modified Kuo interaction with the above core and model space are employed. Most of our calculations in this region were performed with this effective interaction. However, jj44b interaction has been found to be better for $^{70}$Zn. After ensuring that DSM gives good description of the spectroscopic properties of low-lying levels in these three nuclei considered, the NTME are calculated. The deduced half-lives with these NTME, assuming neutrino mass is 1 eV, are $9.6 \\times 10^{25}$yr, $1.9 \\times 10^{27}$yr and $1.95 \\times 10^{24}$yr for $^{70}$Zn, $^{80}$Se and $^{82}$Se, respectively.

  6. Canny edge-based deformable image registration

    Kearney, Vasant; Huang, Yihui; Mao, Weihua; Yuan, Baohong; Tang, Liping


    This work focuses on developing a 2D Canny edge-based deformable image registration (Canny DIR) algorithm to register in vivo white light images taken at various time points. This method uses a sparse interpolation deformation algorithm to sparsely register regions of the image with strong edge information. A stability criterion is enforced which removes regions of edges that do not deform in a smooth uniform manner. Using a synthetic mouse surface ground truth model, the accuracy of the Canny DIR algorithm was evaluated under axial rotation in the presence of deformation. The accuracy was also tested using fluorescent dye injections, which were then used for gamma analysis to establish a second ground truth. The results indicate that the Canny DIR algorithm performs better than rigid registration, intensity corrected Demons, and distinctive features for all evaluation matrices and ground truth scenarios. In conclusion Canny DIR performs well in the presence of the unique lighting and shading variations associated with white-light-based image registration.

  7. Slope deformations in high-mountain regions as observed by InSAR: Examples from the Cordillera Blanca, Peru

    Frey, Holger; Strozzi, Tazio; Caduff, Rafael; Huggel, Christian; Klimeš, Jan; Vilímek, Vít; Wiesmann, Andreas; Kääb, Andreas; Cochachin, Alejo; Plummer, Stephen


    the dry period. Data archives of spaceborne SAR sensors such as ERS-1/2, ENVISAT, ALOS PALSAR-1/2, TerraSAR-X, Radarsat-2 and Sentinel-1 provide information reaching back to the 1990ies, allowing for detection and analysis of both current and past processes. Environmental conditions in the Peruvian Andes are particularly favourable for InSAR analyses, with an extended period of mostly cloud-free conditions during austral winter (dry season), sparse vegetation cover and only very limited snow coverage, factors that in other regions often limit the potential of this technology. This contribution shows the potential of InSAR products, providing unique information on slope deformations and surface displacements as identified as an important information source for integrative hazard assessments and glaciological investigations in high-mountain regions. In particular in combination with field investigations this technology is very powerful, not only for hazard research, but for other types of applications related to surface displacements and terrain deformations. In regions like the Cordillera Blanca, where a variety of potentially hazardous and interacting processes are present, often under conditions beyond historical evidences, such data products provide invaluable information for hazard assessments, early detection of hazard potentials, and a basis for prioritization and decision-making by the authorities.

  8. Modeling of Developing Inhomogeneities in the Ferrite Microstructure and Resulting Mechanical Properties Induced by Deformation in the Two-Phase Region

    Majta, J; Zurek, A.K.; Pietrzyk, M.


    The differences in microstructure development of hot deformed steels in the austenite and two-phase region have been effectively described using an integrated computer modeling process. In general, the complete model presented here takes into account kinetics of recrystallization, precipitation, phase transformation, recrystallized austenite grain size, ferrite grain size, and the resulting mechanical properties. The transformation submodel of niobium-microalloyed steels is based on the nucleation and grain growth theory and additivity rule. The thermomechanical part of the modeling process was effectively carried out using the finite element method. Results were obtained in different temperatures, strain rates, and range of deformation. The thermomechanical treatments are different for two grades of niobium-steels to make possible analysis of the resulting structure and properties for different histories of deformation and chemical composition.

  9. Computational Study of Axial Fatigue for Peripheral Nitinol Stents

    Meoli, Alessio; Dordoni, Elena; Petrini, Lorenza; Migliavacca, Francesco; Dubini, Gabriele; Pennati, Giancarlo


    Despite their success as primary treatment for vascular diseases, Nitinol peripheral stents are still affected by complications related to fatigue failure. Hip and knee movements during daily activities produce large and cyclic deformations of the superficial femoral artery, that concomitant to the effects of pulsatile blood pressure, may cause fatigue failure in the stent. Fatigue failure typically occurs in cases of very extended lesions, which often require the use of two or more overlapping stents. In this study, finite element models were used to study the fatigue behavior of Nitinol stents when subjected to cyclic axial compression in different conditions. A specific commercial Nitinol stent was chosen for the analysis and subjected to cyclic axial compression typical of the femoral vascular region. Three different configurations were investigated: stent alone, stent deployed in a tube, and two overlapping stents deployed in a tube. Results confirm that stent oversizing has an influence in determining both the mean and amplitude strains induced in the stent and plays an important role in determining the fatigue response of Nitinol stents. In case of overlapping stents, numerical results suggest higher amplitude strains concentrate in the region close to the overlapping portion where the abrupt change in stiffness causes higher cyclic compression. These findings help to explain the high incidence of stent fractures observed in various clinical trials located close to the overlapping portion.

  10. Reconstructions of the axial muscle insertions in the occipital region of dinosaurs: evaluations of past hypotheses on marginocephalia and tyrannosauridae using the extant phylogenetic bracket approach.

    Tsuihiji, Takanobu


    The insertions of the cervical axial musculature on the occiput in marginocephalian and tyrannosaurid dinosaurs have been reconstructed in several studies with a view to their functional implications. Most of the past reconstructions on marginocephalians, however, relied on the anatomy of just one clade of reptiles, Lepidosauria, and lack phylogenetic justification. In this study, these past reconstructions were evaluated using the Extant Phylogenetic Bracket approach based on the anatomy of various extant diapsids. Many muscle insertions reconstructed in this study were substantially different from those in the past studies, demonstrating the importance of phylogenetically justified inferences based on the conditions of Aves and Crocodylia for reconstructing the anatomy of non-avian dinosaurs. The present reconstructions show that axial muscle insertions were generally enlarged in derived marginocephalians, apparently correlated with expansion of their parietosquamosal shelf/frill. Several muscle insertions on the occiput in tyrannosaurids reconstructed in this study using the Extant Phylogenetic Bracket approach were also rather different from recent reconstructions based on the same, phylogenetic and parsimony-based method. Such differences are mainly due to differences in initial identifications of muscle insertion areas or different hypotheses on muscle homologies in extant diapsids. This result emphasizes the importance of accurate and detailed observations on the anatomy of extant animals as the basis for paleobiological inferences such as anatomical reconstructions and functional analyses.

  11. Direct contribution of axial impact compressive load to anterior tibial load during simulated ski landing impact.

    Yeow, C H; Lee, P V S; Goh, J C H


    Anterior tibial loading is a major factor involved in the anterior cruciate ligament (ACL) injury mechanism during ski impact landing. We sought to investigate the direct contribution of axial impact compressive load to anterior tibial load during simulated ski landing impact of intact knee joints without quadriceps activation. Twelve porcine knee specimens were procured. Four specimens were used as non-impact control while the remaining eight were mounted onto a material-testing system at 70 degrees flexion and subjected to simulated landing impact, which was successively repeated with incremental actuator displacement. Four specimens from the impacted group underwent pre-impact MRI for tibial plateau angle measurements while the other four were subjected to histology and microCT for cartilage morphology and volume assessment. The tibial plateau angles ranged from 29.4 to 38.8 degrees . There was a moderate linear relationship (Y=0.16X; R(2)=0.64; p<0.001) between peak axial impact compressive load (Y) and peak anterior tibial load (X). The anterior and posterior regions in the impacted group sustained surface cartilage fraying, superficial clefts and tidemark disruption, compared to the control group. MicroCT scans displayed visible cartilage deformation for both anterior and posterior regions in the impacted group. Due to the tibial plateau angle, increased axial impact compressive load can directly elevate anterior tibial load and hence contribute to ACL failure during simulated landing impact. Axial impact compressive load resulted in shear cartilage damage along anterior-posterior tibial plateau regions, due to its contribution to anterior tibial loading. This mechanism plays an important role in elevating ACL stress and cartilage deformation during impact landing.


    J. Huffer


    The purpose of this calculation is to develop axial profiles for estimating the axial variation in burnup of a boiling water reactor (BWR) assembly spent nuclear fuel (SNF) given the average burnup of an assembly. A discharged fuel assembly typically exhibits higher burnup in the center and lower burnup at the ends of the assembly. Criticality safety analyses taking credit for SNF burnup must account for axially varying burnup relative to calculations based on uniformly distributed assembly average burnup due to the under-burned tips. Thus, accounting for axially varying burnup in criticality analyses is also referred to as accounting for the ''end effect'' reactivity. The magnitude of the reactivity change due to ''end effect'' is dependent on the initial assembly enrichment, the assembly average burnup, and the particular axial profile characterizing the burnup distribution. The set of bounding axial profiles should incorporate multiple BWR core designs and provide statistical confidence (95 percent confidence that 95 percent of the population is bound by the profile) that end nodes are conservatively represented. The profiles should also conserve the overall burnup of the fuel assembly. More background on BWR axial profiles is provided in Attachment I.

  13. [Management of axial spondyloarthritis].

    Kiltz, U; Baraliakos, X; Braun, J


    The term spondyloarthritis (SpA) is now increasingly used to classify and diagnose patients who are characterized by inflammation in the axial skeleton and peripheral manifestations (arthritis and enthesitis). The management of SpA should be tailored according to the current manifestations of the disease, the disease activity and functional impairment. The current article focuses on diagnosis and therapy in patients with axial SpA. Diagnostic procedures are discussed in light of diagnostic utility and feasibility in daily routine care. Cornerstones of treatment in patients with axial SpA are a combination of regular exercise and pharmacological treatment options aiming at anti-inflammatory strategies.

  14. Deep inelastic reactions and isomers in neutron-rich nuclei across the perimeter of the A = 180-190 deformed region

    Dracoulis G.D.


    Full Text Available Recent results on high-spin isomers populated in deep-inelastic reactions in the transitional tungsten-osmium region are outlined with a focus on 190Os, 192Os and 194Os. As well as the characterization of several two-quasinutron isomers, the 12+ and 20+ isomers in 192Os are interpreted as manifestations of maximal rotation alignment within the neutron i13/2 and possibly proton h11/2 shells at oblate deformation.

  15. Tectonic property and deformation history of Sangzhi-Shimen synclinorium corridor profile in western margin region of Hunan-hubei Province

    郭建华; 王明艳; 朱美衡; 刘学锋; 张或丹; 刘辰生


    The Sangzhi-Shimen synclinorium, which is in the western margin region of the Hunan-Hubei Province and as the southeast part of the middle Yangtze platform, is a second-level tectonics unit in the south of this region.Along the profile, it can be divided into 5 third-level structure belts. By the comprehensive interpretation of seismic data and magnetotelluric (MT) sounding data, it is found that the surface structure is not in accordance with that of the underground, and this un-coordination can be conducted by many decollement surfaces between the layers.There are three periods of deformation in its geo-history in this region: before the early Yanshan stage, during the early Yanshan stage and after the early Yanshan stage, while the main deformation period is during the early Yanshan stage. And the mechanism of deformation is the thrust faults in basement, which are controlled by many decollements, in addition to the decollement of the cap-rock.

  16. Volcano-tectonic deformation in the Kivu Region, Central Africa: Results from six years of continuous GNSS observations of the Kivu Geodetic Network (KivuGNet)

    Geirsson, Halldor; d'Oreye, Nicolas; Mashagiro, Niche; Syauswa, Muhindo; Celli, Gilles; Kadufu, Benjamin; Smets, Benoît; Kervyn, François


    We present an overview of the installation, operation, and initial results of the 15-station KivuGNet (Kivu Geodetic Network) in the Kivu Region, Central Africa. The network serves primarily as a research and monitoring tool for active volcanic, earthquake, and plate boundary processes in the region. Continuous operation of in-situ measurement networks in naturally and politically harsh environments is challenging, but has proven fruitful in this case. During the operation of the network since 2009, KivuGNet has captured: co-eruptive deformation from two eruptions of Nyamulagira (in 2010 and 2011-2012); inter-eruptive deformation, which we interpret as a combination of plate motion across the Western - East Africa Rift, and decreasing deep-seated magma accumulation under the Nyiragongo-Nyamulagira region; co-seismic deformation from the Mw5.8 August 7, 2015 Lwiro earthquake at the western border of Lake Kivu. We hope that this study will serve as a motivation for further implementation of in-situ geodetic networks in under-monitored and under-studied sections of the East African Rift.

  17. Axial Halbach Magnetic Bearings

    Eichenberg, Dennis J.; Gallo, Christopher A.; Thompson, William K.


    Axial Halbach magnetic bearings have been investigated as part of an effort to develop increasingly reliable noncontact bearings for future high-speed rotary machines that may be used in such applications as aircraft, industrial, and land-vehicle power systems and in some medical and scientific instrumentation systems. Axial Halbach magnetic bearings are passive in the sense that unlike most other magnetic bearings that have been developed in recent years, they effect stable magnetic levitation without need for complex active control.

  18. Fractal analysis of INSAR and correlation with graph-cut based image registration for coastline deformation analysis: post seismic hazard assessment of the 2011 Tohoku earthquake region

    P. K. Dutta


    Full Text Available Satellite imagery for 2011 earthquake off the Pacific coast of Tohoku has provided an opportunity to conduct image transformation analyses by employing multi-temporal images retrieval techniques. In this study, we used a new image segmentation algorithm to image coastline deformation by adopting graph cut energy minimization framework. Comprehensive analysis of available INSAR images using coastline deformation analysis helped extract disaster information of the affected region of the 2011 Tohoku tsunamigenic earthquake source zone. We attempted to correlate fractal analysis of seismic clustering behavior with image processing analogies and our observations suggest that increase in fractal dimension distribution is associated with clustering of events that may determine the level of devastation of the region. The implementation of graph cut based image registration technique helps us to detect the devastation across the coastline of Tohoku through change of intensity of pixels that carries out regional segmentation for the change in coastal boundary after the tsunami. The study applies transformation parameters on remotely sensed images by manually segmenting the image to recovering translation parameter from two images that differ by rotation. Based on the satellite image analysis through image segmentation, it is found that the area of 0.997 sq km for the Honshu region was a maximum damage zone localized in the coastal belt of NE Japan forearc region. The analysis helps infer using matlab that the proposed graph cut algorithm is robust and more accurate than other image registration methods. The analysis shows that the method can give a realistic estimate for recovered deformation fields in pixels corresponding to coastline change which may help formulate the strategy for assessment during post disaster need assessment scenario for the coastal belts associated with damages due to strong shaking and tsunamis in the world under disaster risk

  19. Death Receptor 3 (TNFRSF25 Increases Mineral Apposition by Osteoblasts and Region Specific New Bone Formation in the Axial Skeleton of Male DBA/1 Mice

    Fraser L. Collins


    Full Text Available Objectives. Genome wide association studies identified TNFSF member TNF-like protein 1A (TL1A, TNFSF15 as a potential modulator of ankylosing spondylitis (AS. TL1A is the only confirmed TNFSF ligand of death receptor 3 (DR3, TNFRSF25; however, its role in disease pathology is not characterised. We evaluated DR3’s role in controlling osteoblast- (OB- dependent bone formation in vitro and in vivo. Methods. Osteoprogenitor cells and OB were cultured from male DR3-deficient (DR3ko and wild-type (DR3wt DBA/1 mice. DR3 and RANKL expression were tested by flow cytometry. Alkaline phosphatase and mineralization were quantified. Osteopontin, osteoprotegerin, and pro MMP-9 were measured by ELISA. A fluorescent probe (BoneTag was used to measure in vivo mineralization in 10-month-old mice. Results. DR3 was expressed on osteoprogenitors and OB from DR3wt mice. Alkaline phosphatase, osteopontin, and mineral apposition were significantly elevated in DR3wt cultures. Levels of RANKL were comparable whilst osteoprotegerin was significantly increased in DR3wt cultures. In vivo incorporation of BoneTag was significantly lower in the thoracic vertebrae of 10-month-old DR3ko mice. Conclusions. These data identify new roles for DR3 in regulating OB-dependent bone mineral apposition. They potentially begin to explain the atypical pattern of new bone formation observed in the axial skeleton of grouped, aging DBA/1 mice.

  20. The Welding Process and Deformation Control of Large Axial-Flow Compressor Casing%大型轴流压缩机机壳焊接工艺及变形控制

    徐金; 梁彦荣; 杨建伟; 张璞姚刚


    In this paper, the structure features of large type axial compressor welding casing was analyzed. The welding process method of (Ar) 80% + (CO2) 20%argon-rich mixed gas shielded arc welding was selected, then relative process testing was carried out according to standards. Finally the casing welding distortion was effective controlled by logical sequence of welding, and the performance indexes after welding all met the design requirements.%  分析了大型轴流压缩机焊接机壳的结构特点,选择(Ar)80%+(CO2)20%富氩混合气体保护焊的焊接工艺方法,并按标准进行了相关工艺试验,通过合理的拼装顺序有效控制了机壳的焊接变形,焊后各项指标达到设计要求。

  1. Seismites in slowly deforming regions - evidence for diffuse seismicity in the northern Ejina Basin (Gaxun Nur Basin)

    Rudersdorf, Andreas; Hartmann, Kai; Reicherter, Klaus


    Past earthquakes leave various types of evidence on the Earth's surface. Seismic waves in water-saturated sediments lead to the deformation of original bedding, unconformities and event layers. The term "seismite" was introduced to describe the various co-seismic effects of earthquakes on sediments that range from principally brittle deformation (e.g., neptunian dykes, hydrofracturing) to soft-sediment deformation (e.g., liquefaction, convolution, seismoslumps). The Gobi belt of left-lateral transpression between the active deformation zones of the Tibetan Plateau - driven by the India-Eurasian continental collision, and the Gobi-Altai mountain ranges - showing large-scale faulting as far-field responses of above-named collision, exhibits large and remote desert environments with rugged and low topography that are overprinted by strong eolian erosion by competing wind systems. The Ejina Basin (Gaxun Nur Basin, Inner Mongolia) has been extensively studied and shows evidence for neotectonic faulting (indirectly dated by affected lacustrine sediments) through detected lineaments, morphotectonic investigation and geophysical reconnaissance. The instrumental seismicity is low. Different modes of faulting are discussed, with both WSW-ENE and conjugate trending strike-slip faulting with associated pull-apart basins, as well as far-field-induced NW-SE trending thrusts, being found. The basin is a huge endorheic delta built by the Hei River (chin. Heihe, mong. Ruoshui) and comprises Quaternary sedimentary successions up to 300 m in thickness, which overlie Neogene and Mesozoic sedimentary bedrock. The Quaternary sedimentary successions consist of changing intercalations of eolian and fluvial sands, lacustrine silts and clays and playa evaporites. Positive landforms, such as yardangs (wind-sculpted clay terraces) in the lower reaches of the Hei River (northern Ejina Basin) serve as valuable outcrops for paleoseismic investigation. They exhibit units of deformed sediments

  2. On the relationship between tibia torsional deformation and regional muscle contractions in habitual human exercises in vivo.

    Yang, Peng-Fei; Kriechbaumer, Andreas; Albracht, Kirsten; Sanno, Maximilian; Ganse, Bergita; Koy, Timmo; Shang, Peng; Brüggemann, Gert-Peter; Müller, Lars Peter; Rittweger, Jörn


    The mechanical relationship between bone and muscle has been long recognized. However, it still remains unclear how muscles exactly load on bone. In this study, utilizing an optical segment tracking technique, the in vivo tibia loading regimes in terms of tibia segment deformation in humans were investigated during walking, forefoot and rear foot stair ascent and running and isometric plantar flexion. Results suggested that the proximal tibia primarily bends to the posterior aspect and twists to the external aspect with respect to the distal tibia. During walking, peak posterior bending and peak torsion occurred in the first half (22%) and second half (76%) of the stance phase, respectively. During stair ascent, two noticeable peaks of torsion were found with forefoot strike (38% and 82% of stance phase), but only one peak of torsion was found with rear foot strike (78% of stance phase). The torsional deformation angle during both stair ascent and running was larger with forefoot strike than rear foot strike. During isometric plantar flexion, the tibia deformation regimes were characterized more by torsion (maximum 1.35°) than bending (maximum 0.52°). To conclude, bending and torsion predominated the tibia loading regimes during the investigated activities. Tibia torsional deformation is closely related to calf muscle contractions, which further confirm the notion of the muscle-bone mechanical link and shift the focus from loading magnitude to loading regimes in bone mechanobiology. It thus is speculated that torsion is another, yet under-rated factor, besides the compression and tension, to drive long bone mechano-adaptation.

  3. The Wassa deposit: A poly-deformed orogenic gold system in southwest Ghana - Implications for regional exploration

    Perrouty, Stéphane; Jessell, Mark W.; Bourassa, Yan; Miller, John; Apau, Daniel; Siebenaller, Luc; Velásquez, Germán; Baratoux, Lenka; Aillères, Laurent; Béziat, Didier; Salvi, Stefano


    The Ashanti greenstone belt in southwest Ghana hosts many gold deposits distinguished by different timing and structural contexts. This study investigates the evolution of the Wassa system by integrating field and geophysical observations. This 4 million ounces (past production and current resources) gold deposit is interpreted to represent the oldest gold mineralization event in West Africa with gold-bearing pyrites aligned and stretched within the S1 ductile fabric. Mineralized quartz-carbonate veins were strongly deformed during the D1 deformation event. Three additional folding events are characterized by hectometer-scale tight to isoclinal folds, by a kilometer-scale synform fold centered on the mine and by a late recumbent metric-scale folds. Because of its early timing, the Wassa system represents a new poly-deformed deposit type in West Africa and highlights a potential for new discoveries in the underexplored meta-volcanic and meta-sedimentary Sefwi Group. Timing of the gold mineralization at the Wassa mine makes this deposit type a possible candidate for the source of the gold contained in the Tarkwa paleoplacer.

  4. Lower Crustal Flow and Its Relation to the Surface Deformation and Stress Distribution in Western Sichuan Region, China

    Yujiang Li; Lianwang Chen; Pei Tan; Hong Li


    The channel flow model was gradually being accepted with the more important multidisci-plinary evidences from geology and geophysics, but how the lower crustal flow influenced the surface de-formation quantitatively was unknown. Here, we develop a three-dimensional viscoelastic model to ex-plore the mechanical relations between the lower crustal flow and the surface deformation in western Si-chuan. Based on numerous tests, our results show that the modeled results fit well with the observed GPS data when the lower crust flows faster than the upper crust about 11 mm/a in the rhombic block, which can be useful to understand the possible mechanism of the surface deformation in western Sichuan. Moreover, taking the Xianshuihe fault as an example, we preliminarily analyze the relation between the active fault and stress field, according to the boundary constraints that deduced from the best model. The results show that the maximum shear stress on the Xianshuihe fault zone is mainly located in the fault terminal, intersections and the bend of the fault geometry, the stress level on the northwestern segment that has the high slip rate is relatively high. Additionally, with the reduction of the Young’s modulus in the fault zone, it’s conducive to generate the greater strain distribution, hence forming the high stress level.

  5. An Investigation on Axial Deformation Behavior of Thin-Wall Unfilled and Filled Tube with Aluminum Alloy (Al-Si7Mg) Foam Reinforced with SiC Particles

    Kumaraswamidhas, L. A.; Rajak, Dipen Kumar; Das, S.


    The objective of this research is to produce superior quality aluminum alloy foam with low relative density and higher resistance against compression deformation. This investigation has studied crash energy capacities of unfilled and filled aluminum alloy foams in mild steel tubes. The foam has been prepared by the melt route process with an addition of 5wt.% silicon carbide particles. The fabricated aluminum alloy foams were characterized by field emission scanning electron microscopy, x-ray diffraction, Fourier transform infrared spectroscopy, and Material Pro analyzer. It was observed that the foam-filled tubes could absorb more energy as compared to the unfilled tubes before reaching the complete densification point. Also, the aluminum alloy foams had better energy absorption capacity during the crash or impact loading. This article demonstrates the excellent ability of aluminum alloy foam application in the field where there is a need to absorb crash energy. It is to be noted that the amount of energy absorption will be greater for low-density foam filled in thin-wall rectangular section tubes. We have seen an increasing trend in the application of aluminum foams inside the thin-wall mild steel tubes for maximum energy absorption.

  6. Soft-impact dynamics of deformable bodies

    Andreaus, Ugo; Chiaia, Bernardino; Placidi, Luca


    Systems constituted by impacting beams and rods of non-negligible mass are often encountered in many applications of engineering practice. The impact between two rigid bodies is an intrinsically indeterminate problem due to the arbitrariness of the velocities after the instantaneous impact and implicates an infinite value of the contact force. The arbitrariness of after-impact velocities is solved by releasing the impenetrability condition as an internal constraint of the bodies and by allowing for elastic deformations at contact during an impact of finite duration. In this paper, the latter goal is achieved by interposing a concentrate spring between a beam and a rod at their contact point, simulating the deformability of impacting bodies at the interaction zones. A reliable and convenient method for determining impact forces is also presented. An example of engineering interest is carried out: a flexible beam that impacts on an axially deformable strut. The solution of motion under a harmonic excitation of the beam built-in base is found in terms of transverse and axial displacements of the beam and rod, respectively, by superimposition of a finite number of modal contributions. Numerical investigations are performed in order to examine the influence of the rigidity of the contact spring and of the ratio between the first natural frequencies of the beam and the rod, respectively, on the system response, namely impact velocity, maximum displacement, spring stretching and contact force. Impact velocity diagrams, nonlinear resonance curves and phase portraits are presented to determine regions of periodic motion with impacts and the appearance of chaotic solutions, and parameter ranges where the functionality of the non-structural element is at risk.

  7. Measuring Regional Changes in the Diastolic Deformation of the Left Ventricle of SHR Rats Using microPET Technology and Hyperelastic Warping



    The objective of this research was to assess applicability of a technique known as hyperelastic warping for the measurement of local strains in the left ventricle (LV) directly from microPET image data sets. The technique uses differences in image intensities between template (reference) and target (loaded) image data sets to generate a body force that deforms a finite element (FE) representation of the template so that it registers with the target images. For validation, the template image was defined as the end-systolic microPET image data set from a Wistar Kyoto (WKY) rat. The target image was created by mapping the template image using the deformation results obtained from a FE model of diastolic filling. Regression analysis revealed highly significant correlations between the simulated forward FE solution and image derived warping predictions for fiber stretch (R2 = 0.96), circumferential strain (R2 = 0.96), radial strain (R2 = 0.93), and longitudinal strain (R2 = 0.76) (p<0.001for all cases). The technology was applied to microPET image data of two spontaneously hypertensive rats (SHR) and a WKY control. Regional analysis revealed that, the lateral freewall in the SHR subjects showed the greatest deformation compared with the other wall segments. This work indicates that warping can accurately predict the strain distributions during diastole from the analysis of microPET data sets.

  8. Altered Axial Skeletal Development

    The axial skeleton is routinely examined in standard developmental toxicity bioassays and has proven to be sensitive to a wide variety of chemical agents. Dysmorphogenesis in the skull, vertebral column and ribs has been described in both human populations and in laboratory anima...


    C.G. Xu; G.H. Liu; G.S. Ren; Z. Shen; C.P. Ma; W. W. Ren


    A flexible technique of hot working of bars by axial feed rolling was introduced. The processdeformation, strain field, stress field, and temperature field of the parts are analyzed by finite elementmethod (FEM)-simulation software DEFORM-3D. The material flow rule and tool load have beeninvestigated.

  10. Surface nanoscale axial photonics

    Sumetsky, M


    Dense photonic integration promises to revolutionize optical computing and communications. However, efforts towards this goal face unacceptable attenuation of light caused by surface roughness in microscopic devices. Here we address this problem by introducing Surface Nanoscale Axial Photonics (SNAP). The SNAP platform is based on whispering gallery modes circulating around the optical fiber surface and undergoing slow axial propagation readily described by the one-dimensional Schr\\"odinger equation. These modes can be steered with dramatically small nanoscale variation of the fiber radius, which is quite simple to introduce in practice. The extremely low loss of SNAP devices is achieved due to the fantastically low surface roughness inherent in a drawn fiber surface. In excellent agreement with the developed theory, we experimentally demonstrate localization of light in quantum wells, halting light by a point source, tunneling through potential barriers, dark states, etc. This demonstration, prototyping basi...

  11. Scalar Resonances in Axially Symmetric Spacetimes

    Ranea-Sandoval, Ignacio F


    We study properties of resonant solutions to the scalar wave equation in several axially symmetric spacetimes. We prove that non-axial resonant modes do not exist neither in the Lanczos dust cylinder, the $(2+1)$ extreme BTZ spacetime nor in a class of simple rotating wormhole solutions. Moreover, we find unstable solutions to the wave equation in the Lanczos dust cylinder and in the $r^2 <0$ region of the extreme $(2+1)$ BTZ spacetime, two solutions that possess closed timelike curves. Similarities with previous results obtained for the Kerr spacetime are explored.

  12. 轴型肌皮瓣移植修复颈胸部难愈性创面%Axial myocutaneous flap transplantation for repair of refractory wound in the cervico-thoracic region

    黎洪棉; 高建华; 姜平; 黎小间


    BACKGROUND: Axial myocutaneous flap transplantation is the common method for repair of various refractory. Thir method had certain blindness in judgment of the main arteiies in flaps before surgery in the past. Therefore, it is importantto develop a more accurate method.OBJECTIVE: To introduce the application experiences of axial myocutaneous flap in repair of refractory wound in the cervico-thoracic region.METHODS: Color dopplerflow imaging was used to examine the starting point, branching point, exterior diameter, vessel trend, vessel length and hemodynamic parameters of the main arteries of 4 types flaps from 62 cases. The axial myocutaneous flaps were designed according to the detection. The sizes of the axial myocutaneous flaps ranged from(£cfTK7cm)to(18cnft13cm;L RESULTS AND CONCLUSION: According to color dopplerflow imaging, one case of thoracodorsal artery had slow blood flow, rough vascular wall and obvious arteriosclerosis, and the other cases were with smooth blood flew and vascular wall, and without embolism, arteriosclerosis or absence of blood vessel. The starting point, branching point, exterior diameter, vessel trend and anatomic layers of the detected arteries were displayed clearly, in consistency with the results of operation; the flap completely survived in 60 cases with primary healing; distal partial necrosis occurred in 2 cases and was cured by symptomatic treatment. All the cases were followed up for4weeks to 6 years. 24 months in average, and the flaps were with a normal color, good texture and satisfactory appearance. Choosing a suitable pedicled musculo cutaneous flap for refractory wound in cervico-thoracic region according to specific conditions can achieve satisfactoryfunction and appearance. Color dopplerfloAi imaging e asimple, inturtri/e and and non-invashse method to judge blood vessel of axial myocutaneous flaps, and can guide the axial myocutaneous flap transplantation.%背景:轴型肌皮瓣移植是当前修复各种难愈

  13. Helium release during shale deformation: Experimental validation

    Bauer, Stephen J.; Gardner, W. Payton; Heath, Jason E.


    This work describes initial experimental results of helium tracer release monitoring during deformation of shale. Naturally occurring radiogenic 4He is present in high concentration in most shales. During rock deformation, accumulated helium could be released as fractures are created and new transport pathways are created. We present the results of an experimental study in which confined reservoir shale samples, cored parallel and perpendicular to bedding, which were initially saturated with helium to simulate reservoir conditions, are subjected to triaxial compressive deformation. During the deformation experiment, differential stress, axial, and radial strains are systematically tracked. Release of helium is dynamically measured using a helium mass spectrometer leak detector. Helium released during deformation is observable at the laboratory scale and the release is tightly coupled to the shale deformation. These first measurements of dynamic helium release from rocks undergoing deformation show that helium provides information on the evolution of microstructure as a function of changes in stress and strain.

  14. From superdeformation to extreme deformation and clusterization in the N ≈Z nuclei of the A ≈40 mass region

    Ray, D.; Afanasjev, A. V.


    A systematic search for extremely deformed structures in the N ≈Z nuclei of the A ≈40 mass region has been performed for the first time in the framework of covariant density functional theory. At spin zero such structures are located at high excitation energies, which prevents their experimental observation. The rotation acts as a tool to bring these exotic shapes to the yrast line or its vicinity so that their observation could become possible with future generation of γ -tracking (or similar) detectors such as GRETA and AGATA. The major physical observables of such structures (such as transition quadrupole moments, as well as kinematic and dynamic moments of inertia), the underlying single-particle structure and the spins at which they become yrast or near yrast, are defined. The search for the fingerprints of clusterization and molecular structures is performed and the configurations with such features are discussed. The best candidates for observation of extremely deformed structures are identified. For several nuclei in this study (such as 36Ar), the addition of several spin units above the currently measured maximum spin of 16 ℏ will inevitably trigger the transition to hyper- and megadeformed nuclear shapes.

  15. 轴流泵叶轮出口尾迹区非定常压力和速度场特性%Property of unsteady pressure and meridional velocity in wake region of axial-flow pump impeller

    张德胜; 施卫东; 李通通; 张华; 关醒凡


    为了分析轴流泵叶轮出口尾迹和势流交替干扰特性,基于RNGκ-ε湍流模型和SIMPLE算法,对南水北调工程用轴流泵模型进行了数值计算.通过定常预测的外特性结果与试验值进行比较,验证了计算网格和湍流模型的适用性,并在此基础上计算了轴流泵叶轮出口尾迹区非定常流场特性.研究结果表明,通过轴流泵全流场数值计算结果与试验值对比,在最优工况下计算扬程相对误差为4.56%,效率相对误差为2.78%,较好反映了轴流泵内部流动特性;在小流量工况下,轴流泵叶轮出口圆周方向轴面速度存在与叶片数相同的3个主波峰和3个次波峰;随着流量增大,叶轮出口圆周方向速度分布图中的波峰与导叶叶片数相同.在小流量工况和设计工况下,叶轮出口尾迹区压力脉动时域图出现3个主波峰,随着流量增大,额外产生了3个次波峰.基于FFT变换发现不同流量工况下的压力脉动主频均以叶频为主,其他谐频以叶频为基频,呈倍数出现,且主频的幅值随着流量减小而迅速上升.%In order to study the rotor-stator interaction in the wake region of the axial-flow impeller, the axial-flow pump model for South-to-North Water Diversion Project model was simulated based RNG k-e turbulence model and the SIMPLE algorithm. The calculated values by steady simulation were compared with the experimental results to verify the computational grid and the applicability of turbulence model, and the unsteady field was simulated based on the steady results. The numerical results show that the relative error of Head is 4.56% and efficiency is 2.78% in optimal condition compared with the experimental data. In small flow rata condition, three peaks and three second peaks occur on the meridional velocity at axial flow impeller outlet in the circumferential direction. As the flow rate increases, the number of the velocity peak at impeller outlet is same to the guide

  16. Deformation in nanocrystalline metals

    Helena Van Swygenhoven; Julia R. Weertman


    It is now possible to synthesize polycrystalline metals made up of grains that average less than 100 nm in size. Such nanocrystalline metals contain a significant volume fraction of interfacial regions separated by nearly perfect crystals. The small sizes involved limit the conventional operation of dislocation sources and thus a fundamental question arises: how do these materials deform plastically? We review the current views on deformation mechanisms in nanocrystalline, face-centered cubic...

  17. Critical Axial Load

    Walt Wells


    Full Text Available Our objective in this paper is to solve a second order differential equation for a long, simply supported column member subjected to a lateral axial load using Heun's numerical method. We will use the solution to find the critical load at which the column member will fail due to buckling. We will calculate this load using Euler's derived analytical approach for an exact solution, as well as Euler's Numerical Method. We will then compare the three calculated values to see how much they deviate from one another. During the critical load calculation, it will be necessary to calculate the moment of inertia for the column member.

  18. Two regions of seafloor deformation generated the tsunami for the 13 November 2016, Kaikoura, New Zealand earthquake

    Bai, Yefei; Lay, Thorne; Cheung, Kwok Fai; Ye, Lingling


    The 13 November 2016 Kaikoura, New Zealand, Mw 7.8 earthquake ruptured multiple crustal faults in the transpressional Marlborough and North Canterbury tectonic domains of northeastern South Island. The Hikurangi trench and underthrust Pacific slab terminate in the region south of Kaikoura, as the subdution zone transitions to the Alpine fault strike-slip regime. It is difficult to establish whether any coseismic slip occurred on the megathrust from on-land observations. The rupture generated a tsunami well recorded at tide gauges along the eastern coasts and in Chatham Islands, including a 4 m crest-to-trough signal at Kaikoura where coastal uplift was about 1 m, and at multiple gauges in Wellington Harbor. Iterative modeling of teleseismic body waves and the regional water-level recordings establishes that two regions of seafloor motion produced the tsunami, including an Mw 7.6 rupture on the megathrust below Kaikoura and comparable size transpressional crustal faulting extending offshore near Cook Strait.

  19. Determining Aerodynamic Loads Based on Optical Deformation Measurements

    Liu, Tianshu; Barrows, D. A.; Burner, A. W.; Rhew, R. D.


    This paper describes a videogrammetric technique for determining aerodynamic loads based on optical elastic deformation measurements. The data reduction methods are developed to extract the normal force and pitching moment from beam deformation data. The axial force is obtained by measuring the axial translational motion of a movable shaft in a spring/bearing device. Proof-of-concept calibration experiments are conducted to assess the accuracy of this optical technique.

  20. Paleomagnetic Study of a Miocene Deformation in a Region Close to the Camargo Volcanic Field, Chihuahua, Mexico

    Wogau-Chong, K.; Bohnel, H.; Aranda Gomez, J.


    The Sierra the Aguachile is a Miocene volcanic sequence located in the SE of Chihuahua State NW of the Camargo volcanic field and belongs to the Agua Mayo Group, which unconformably overlays Mesozoic calcareous units. The Sierra de Aguachile sequence defines a structure that may be interpreted as a plunging fold, which could be the result of a reactivation of the San Marcos Fault. This major fault is well known more to the east but may extend into the study area where it would be covered by the younger volcanic sequences; its main activity has been reported to be during the the Neocomian with reactivation phases in the Paleogene and Miocene. To test if the observed structure is the result of a tectonic deformation that happened after the emplacement of the volcanic sequence, a paleomagnetic study was carried out. A total of 14 sites were sampled from different parts of the structure, all in the capping ignimbrite layers. Site mean directions were determined using AF demagnetization. The fold test was applied to analyze if the remanence was acquired in situ or before the proposed folding. Precision parameters k before and after application of the tectonic corrections are 25.38 and 31.43, respectively. This indicates that the Sierra de Aguachile indeed was folded after emplacement of the ignimbrites, which restricts the age of the corresponding tectonic event to be younger than 31.3 +/- 0.7 Ma. Due to the gentle folding though, the difference in precision parameters is not significant at the 95% probability level.

  1. Tempering/ageing in region 50 – 600 °C of quenched and cold deformed 585 GOLD alloy for jewelry production

    R. Perić


    Full Text Available Numerous gold alloys posses the ability for thermal hardening, and this property is attractive for improving jewels strength, because the most noble alloys are weak. The thermal treating below the recrystallization temperature, is kind of tempering but also age-hardening. In this paper is made an attempt for studying the possibility for thermal hardening of 585 golden alloy. The goal is to increase the mechanical properties. Those demands could be reached by metallurgical controlling of phase transformations аnd proper thermal treating. Here is studied behavior of quenched and cold deformed gold alloy 585 after tempering/ageing in temperature region 50 - 600 °C, in intervals of 50 °C. The highest hardness values are obtained at temperatures about 200 °C for both initial states.

  2. A new interpretation of deformation rates in the Snake River Plain and adjacent basin and range regions based on GPS measurements

    Payne, S. J.; McCaffrey, R.; King, R. W.; Kattenhorn, S. A.


    Within the Northern Basin and Range Province, USA, we estimate horizontal velocities for 405 sites using Global Positioning System (GPS) phase data collected from 1994 to 2010. The velocities, together with geologic, volcanic, and earthquake data, reveal a slowly deforming region within the Snake River Plain in Idaho and Owyhee-Oregon Plateau in Oregon separated from the actively extending adjacent Basin and Range regions by shear. Our results show a NE-oriented extensional strain rate of 5.6 ± 0.7 × 10-9 yr-1 in the Centennial Tectonic Belt and an ˜E-oriented extensional strain rate of 3.5 ± 0.2 × 10-9 yr-1 in the Great Basin. These extensional rates contrast with the very low strain rate within the 125 km × 650 km region of the Snake River Plain and Owyhee-Oregon Plateau, which is indistinguishable from zero (-0.1 ± 0.4 × 10-9 yr-1). Inversions of the velocities with dyke-opening models indicate that rapid extension by dyke intrusion in volcanic rift zones, as previously hypothesized, is not currently occurring in the Snake River Plain. This slow internal deformation, in contrast to the rapidly extending adjacent Basin and Range regions, indicates shear along the boundaries of the Snake River Plain. We estimate right-lateral shear with slip rates of 0.3-1.4 mm yr-1 along the northwestern boundary adjacent to the Centennial Tectonic Belt and left-lateral oblique extension with slip rates of 0.5-1.5 mm yr-1 along the southeastern boundary adjacent to the Intermountain Seismic Belt. The fastest lateral shearing evident in the GPS occurs near the Yellowstone Plateau where strike-slip focal mechanisms and faults with observed strike-slip components of motion are documented. The regional velocity gradients are best fit by nearby poles of rotation for the Centennial Tectonic Belt, Snake River Plain, Owyhee-Oregon Plateau, and eastern Oregon, indicating that clockwise rotation is not locally driven by Yellowstone hotspot volcanism, but instead by extension to the

  3. Open-Axial-Field Magnet at ISR intersection I8


    This axial field spectrometer left the central collision region unobstructed in order to ease analysis of secondary particles emitted at large angle. The ISR circulating beams were passing through a hole in the magnet poles.

  4. Axial flow heat exchanger devices and methods for heat transfer using axial flow devices

    Koplow, Jeffrey P.


    Systems and methods described herein are directed to rotary heat exchangers configured to transfer heat to a heat transfer medium flowing in substantially axial direction within the heat exchangers. Exemplary heat exchangers include a heat conducting structure which is configured to be in thermal contact with a thermal load or a thermal sink, and a heat transfer structure rotatably coupled to the heat conducting structure to form a gap region between the heat conducting structure and the heat transfer structure, the heat transfer structure being configured to rotate during operation of the device. In example devices heat may be transferred across the gap region from a heated axial flow of the heat transfer medium to a cool stationary heat conducting structure, or from a heated stationary conducting structure to a cool axial flow of the heat transfer medium.

  5. Chemical U-Th-Pb Monazite Dating of Deformations versus Pluton Emplacement and the Proterozoic History of the Arkansas River Region,Colorado, USA

    CAO Hui


    Five lengthy periods involving multiple phases of cordierite and andalusite growth were revealed by detailed studies of foliation inflection/intersection axes (FIA) preserved in porphyroblasts in schists from the Arkansas River region in Colorado, USA. The regionally consistent character of the succession of five different FIA trends enabled the relative timing of each FIA with respect to the next to be determined. The FIA succession from first to last is: FIA 1 trending W-E, FIA 2 trending SSW-NNE, FIA 3 trending NNW-SSE, FIA 4 trending NW-SE and FIA 5 trending SW-NE. For four of the FIA sets, samples were found containing monazite grains preserved as inclusions. These were dated on an electron microprobe. The ages obtained concur exactly with the FIA succession, with FIA 1 at 1506±15 Ma, FIA 2 at 1467±23 Ma, FIA 3 at 1425±18 Ma, FIA 4 not dated and FIA 5 at 1366±20 Ma.These ages are directly reflected in a succession of plutons in the surrounding region dated by other isotopic approaches, suggesting that deformation, metamorphism and pluton emplacement occurred together episodically, but effectively continuously, for some 140 Ma.

  6. Crustal deformation and seismic measurements in the region of McDonald Observatory, West Texas. [Texas and Northern Chihuahua, Mexico

    Dorman, H. J.


    The arrival times of regional and local earthquakes and located earthquakes in the Basin and Range province of Texas and in the adjacent areas of Chihuahua, Mexico from January 1976 to August 1980 at the UT'NASA seismic array are summarized. The August 1931 Texas earthquake is reevaluated and the seismicity and crustal structure of West Texas is examined. A table of seismic stations is included.

  7. Reactive control of subsonic axial fan noise in a duct.

    Liu, Y; Choy, Y S; Huang, L; Cheng, L


    Suppressing the ducted fan noise at low frequencies without varying the flow capacity is still a technical challenge. This study examines a conceived device consisting of two tensioned membranes backed with cavities housing the axial fan for suppression of the sound radiation from the axial fan directly. The noise suppression is achieved by destructive interference between the sound fields from the axial fan of a dipole nature and sound radiation from the membrane via vibroacoustics coupling. A two-dimensional model with the flow effect is presented which allows the performance of the device to be explored analytically. The air flow influences the symmetrical behavior and excites the odd in vacuo mode response of the membrane due to kinematic coupling. Such an asymmetrical effect can be compromised with off-center alignment of the axial fan. Tension plays an important role to sustain the performance to revoke the deformation of the membrane during the axial fan operation. With the design of four appropriately tensioned membranes covered by a cylindrical cavity, the first and second blade passage frequencies of the axial fan can be reduced by at least 20 dB. The satisfactory agreement between experiment and theory demonstrates that its feasibility is practical.

  8. Slow axial drift in three-dimensional granular tumbler flow

    Zaman, Zafir; D'Ortona, Umberto; Umbanhowar, Paul B.; Ottino, Julio M.; Lueptow, Richard M.


    Models of monodisperse particle flow in partially filled three-dimensional tumblers often assume that flow along the axis of rotation is negligible. We test this assumption, for spherical and double cone tumblers, using experiments and discrete element method simulations. Cross sections through the particle bed of a spherical tumbler show that, after a few rotations, a colored band of particles initially perpendicular to the axis of rotation deforms: particles near the surface drift toward the pole, while particles deeper in the flowing layer drift toward the equator. Tracking of mm-sized surface particles in tumblers with diameters of 8-14 cm shows particle axial displacements of one to two particle diameters, corresponding to axial drift that is 1-3% of the tumbler diameter, per pass through the flowing layer. The surface axial drift in both double cone and spherical tumblers is zero at the equator, increases moving away from the equator, and then decreases near the poles. Comparing results for the two tumbler geometries shows that wall slope causes axial drift, while drift speed increases with equatorial diameter. The dependence of axial drift on axial position for each tumbler geometry is similar when both are normalized by their respective maximum values.

  9. A new interpretation of deformation rates in the Snake River Plain and adjacent basin and range regions based on GPS measurements

    S.J. Payne; R. McCaffrey; R.W. King; S.A. Kattenhorn


    We evaluate horizontal Global Positioning System (GPS) velocities together with geologic, volcanic, and seismic data to interpret extension, shear, and contraction within the Snake River Plain and the Northern Basin and Range Province, U.S.A. We estimate horizontal surface velocities using GPS data collected at 385 sites from 1994 to 2009 and present an updated velocity field within the Stable North American Reference Frame (SNARF). Our results show an ENE-oriented extensional strain rate of 5.9 {+-} 0.7 x 10{sup -9} yr{sup -1} in the Centennial Tectonic belt and an E-oriented extensional strain rate of 6.2 {+-} 0.3 x 10{sup -9} yr{sup -1} in the Intermountain Seismic belt combined with the northern Great Basin. These extensional strain rates contrast with the regional north-south contraction of -2.6 {+-} 1.1 x 10{sup -9} yr{sup -1} calculated in the Snake River Plain and Owyhee-Oregon Plateau over a 125 x 650 km region. Tests that include dike-opening reveal that rapid extension by dike intrusion in volcanic rift zones does not occur in the Snake River Plain at present. This slow internal deformation in the Snake River Plain is in contrast to the rapidly-extending adjacent Basin and Range provinces and implies shear along boundaries of the Snake River Plain. We estimate right-lateral shear with slip rates of 0.5-1.5 mm/yr along the northwestern boundary adjacent to the Centennial Tectonic belt and left-lateral oblique extension with slip rates of <0.5 to 1.7 mm/yr along the southeastern boundary adjacent to the Intermountain Seismic belt. The fastest lateral shearing occurs near the Yellowstone Plateau where strike-slip focal mechanisms and faults with observed strike-slip components of motion are documented. The regional GPS velocity gradients are best fit by nearby poles of rotation for the Centennial Tectonic belt, Idaho batholith, Snake River Plain, Owyhee-Oregon Plateau, and central Oregon, indicating that clockwise rotation is driven by extension to the

  10. Crustal deformation in the south-central Andes backarc terranes as viewed from regional broad-band seismic waveform modelling

    Alvarado, Patricia; Beck, Susan; Zandt, George; Araujo, Mario; Triep, Enrique


    The convergence between the Nazca and South America tectonic plates generates a seismically active backarc region near 31°S. Earthquake locations define the subhorizontal subducted oceanic Nazca plate at depths of 90-120 km. Another seismic region is located within the continental upper plate with events at depths Sierras Pampeanas and is responsible for the large earthquakes that have caused major human and economic losses in Argentina. South of 33°S, the intense shallow continental seismicity is more restricted to the main cordillera over a region where the subducted Nazca plate starts to incline more steeply, and there is an active volcanic arc. We operated a portable broad-band seismic network as part of the Chile-Argentina Geophysical Experiment (CHARGE) from 2000 December to 2002 May. We have studied crustal earthquakes that occurred in the back arc and under the main cordillera in the south-central Andes (29°S-36°S) recorded by the CHARGE network. We obtained the focal mechanisms and source depths for 27 (3.5 Sierras Pampeanas, over the flat-slab segment is dominated by reverse and thrust fault-plane solutions located at an average source depth of 20 km. One moderate-sized earthquake (event 02-117) is very likely related to the northern part of the Precordillera and the Sierras Pampeanas terrane boundary. Another event located near Mendoza at a greater depth (~26 km) (event 02-005) could also be associated with the same ancient suture. We found strike-slip focal mechanisms in the eastern Sierras Pampeanas and under the main cordillera with shallower focal depths of ~5-7 km. Overall, the western part of the entire region is more seismically active than the eastern part. We postulate that this is related to the presence of different pre-Andean geological terranes. We also find evidence for different average crustal models for those terranes. Better-fitting synthetic seismograms result using a higher P-wave velocity, a smaller average S-wave velocity and a

  11. Sedimentary record of regional deformation and dynamics of the thick-skinned southern Puna Plateau, central Andes (26-27°S)

    Zhou, Renjie; Schoenbohm, Lindsay M.; Sobel, Edward R.; Carrapa, Barbara; Davis, Donald W.


    The Puna Plateau, adjacent Eastern Cordillera and the Sierras Pampeanas of the central Andes are largely characterized by thick-skinned, basement-involved deformation. The Puna Plateau hosts ∼N-S trending bedrock ranges bounded by deep-seated reverse faults and sedimentary basins. We contribute to the understanding of thick-skinned dynamics in the Puna Plateau by constraining regional kinematics of the poorly understood southern Puna Plateau through a multidisciplinary approach. On the southeastern plateau, sandstone modal composition and detrital zircon U-Pb and apatite fission-track data from Cenozoic strata indicate basin accumulation during the late Eocene to early Oligocene (∼38-28 Ma). Provenance analysis reveals the existence of a regional-scale basin covering the southern Puna Plateau during late Eocene to early Oligocene time (∼38-28 Ma) that was sourced from both the western plateau and the eastern plateau margin and had a depocenter located to the west. Petrographic and detrital zircon U-Pb data reveal erosion of proximal western and eastern sources after ∼12 Ma, in mid-late Miocene time. This indicates that the regional basin was compartmentalized into small-scale depocenters by the growth of basement-cored ranges continuing into the late Miocene (∼12-8 Ma). We suggest that the Cenozoic history of the southern Puna Plateau records the formation of a regional basin that was possibly driven by lithospheric flexure during the late Eocene to early Oligocene, before the growth of distributed basement-cored ranges starting as early as the late Oligocene.

  12. Experimental Identification and Simulation of Time and/or Rate Dependent Reversible and Irreversible Deformation Regions for both a Titanium and Nickel Alloy

    Arnold, Steven M.; Lerch, Bradley A.; Sellers, Cory


    In this paper time and/or rate dependent deformation regions are experimentally mapped out as a function of temperature. It is clearly demonstrated that the concept of a threshold stress (a stress that delineate reversible and irreversible behavior) is valid and necessary at elevated temperatures and corresponds to the classical yield stress at lower temperatures. Also the infinitely slow modulus, (Es) i.e. the elastic modulus of the material if it was loaded at an infinitely slow strain rate, and the "dynamic modulus", modulus, Ed, which represents the modulus of the material if it is loaded at an infinitely fast rate are used to delineate rate dependent from rate independent regions. As demonstrated at elevated temperatures there is a significant difference between the two modulus values, thus indicating both significant time-dependence and rate dependence. In the case of the nickel-based super alloy, ME3, this behavior is also shown to be grain size specific. Consequently, at higher temperatures viscoelastic behavior exist below k (i.e., the threshold stress) and at stresses above k the behavior is viscoplastic. Finally a multi-mechanism, stress partitioned viscoelastic model, capable of being consistently coupled to a viscoplastic model is characterized over the full temperature range investigated for Ti-6-4 and ME3.

  13. Partial Dynamical Symmetry in Deformed Nuclei

    Leviatan, A. [Racah Institute of Physics, The Hebrew University, Jerusalem 91904 (Israel)


    We discuss the notion of partial dynamical symmetry in relation to nuclear spectroscopy. Explicit forms of Hamiltonians with partial SU(3) symmetry are presented in the framework of the interacting boson model of nuclei. An analysis of the resulting spectrum and electromagnetic transitions demonstrates the relevance of such partial symmetry to the spectroscopy of axially deformed nuclei. {copyright} {ital 1996 The American Physical Society.}

  14. Partial dynamical symmetry in deformed nuclei

    Leviatan, A


    We discuss the notion of partial dynamical symmetry in relation to nuclear spectroscopy. Explicit forms of Hamiltonians with partial SU(3) symmetry are presented in the framework of the interacting boson model of nuclei. An analysis of the resulting spectrum and electromagnetic transitions demonstrates the relevance of such partial symmetry to the spectroscopy of axially deformed nuclei.

  15. Contracture deformity

    Deformity - contracture ... Contracture can be caused by any of the following: Brain and nervous system disorders, such as cerebral ... Follow your health care provider's instructions for treating contracture at home. Treatments may include: Doing exercises and ...

  16. Volcano-tectonic deformation in the Kivu Region, Central Africa: Results from multi-year InSAR time series analysis and continuous GNSS observations of the Kivu Geodetic Network (KivuGNet)

    Geirsson, Halldor; D'Oreye, Nicolas; Smets, Benoît; Nobile, Adriano; Samsonov, Sergey; De Rauw, Dominique; Mashagiro, Niche; Kervyn, Francois


    The Kivu Region in Central Africa is a topographic dome cut by the depression of the western branch of the East African Rift, where the Nubia plate and the Victoria micro-plate are diverging by approximately 2-3 mm/yr (Stamps et al. 2008). Two closely spaced and frequently active volcanoes, Nyiragongo and Nyamulagira, are located at the plate boundary. Here, deformation signals from transient deformation events (i.e. earthquakes, eruptions, rifting episodes, intrusions or other subsurface mass movements) are intertwined with the more perpetual nature of inter-seismic strain accumulation and gradual magma accumulation. Here, we present deformation results from six years of operation of the 15- station KivuGNet (Kivu Geodetic Network) in the Kivu Region and multi-year InSAR time series of the region using the MSBAS approach (Samsonov & d'Oreye, 2012). Since 2009, KivuGNet has captured transient deformation from a) the 2010 eruption of Nyamulagira, b) the 2011-2012 eruption of Nyamulagira c) the Mw5.8 August 7, 2015 Katana earthquake at the western border of Lake Kivu. Importantly, the GPS data also show an ongoing deformation signal, which is most readily explained by long-term magma accumulation under the volcanic region. We use the GPS and InSAR deformation signals to constrain and compare source parameters of simplistic elastic models for the different time periods. Although not well constrained, most of the time periods indicate the presence of a deep (~15-30 km) magmatic source centered approximately under Nyamulagira or to the southeast of Nyamulagira, that inflates between eruptions and deflates during eruptions.

  17. Build Axial Gradient Field by Using Axial Magnetized Permanent Rings


    Axial magnetic field produced by an axial magnetized permanent ring was studied. For two permanent rings, if they are magnetized in the same directions, a nearly uniform axial field can be produced. If they are magnetized in opposite direction,an axial gradient magnetic field can be generated, with the field range changing from -B0 to B0. A permanent magnet with a high axial gradient field was fabricated, the measured results agree with the PANDIRA calculation very well. For wider usage,it is desirable for the field gradient to be changed. Some methods to produce the variable gradient field are presented. These kinds of axial gradient magnetic field can also be used as a beam focusing for linear accelerator if the periodic field can be produced along the beam trajectory. The axial magnetic field is something like a solenoid, large stray field will leak to the outside environment if no method is taken to control them. In this paper, one method is illustrated to shield off the outside leakage field.

  18. Dissipative Axial Inflation

    Notari, Alessio


    We analyze in detail the background cosmological evolution of a scalar field coupled to a massless abelian gauge field through an axial term $\\frac{\\phi}{f_\\gamma} F \\tilde{F}$, such as in the case of an axion. Gauge fields in this case are known to experience tachyonic growth and therefore can backreact on the background as an effective dissipation into radiation energy density $\\rho_R$, which which can lead to inflation without the need of a flat potential. We analyze the system, for momenta $k$ smaller than the cutoff $f_\\gamma$, including numerically the backreaction. We consider the evolution from a given static initial condition and explicitly show that, if $f_\\gamma$ is smaller than the field excursion $\\phi_0$ by about a factor of at least ${\\cal O} (20)$, there is a friction effect which turns on before that the field can fall down and which can then lead to a very long stage of inflation with a generic potential. In addition we find superimposed oscillations, which would get imprinted on any kind of...

  19. Axial stress localization facilitates pressure propagation in gelled pipes

    Norrman, Jens; Skjæraasen, Olaf; Oschmann, Hans-Jörg; Paso, Kristofer; Sjöblom, Johan


    Paraffin wax-oil gels are unique rheological fluids which undergo shear degradation starting at a deformation (shear strain level) of approximately 1%. Flow commencement in pipelines filled with wax-oil gels is a complex hydrodynamic process involving propagation of acoustic, diffusive, and rheological degradation pressure wave fronts. Dynamic simulation informed by qualified rheological relations provides useful insight into the physical nature of these flow processes. Eulerian simulations are presented which emulate known physical phenomena and essential characteristics of wax-gel flow dynamics. A constitutive rheological equation set accounts for deformation-driven reduction in yield stress and viscosity terms. No explicit time-dependent rheological parameters are utilized in the equations. Rheological yielding alters the nature of the dominant pressure wave from inherently diffusive towards self-sharpening. Axial stress localization effectively sequentializes the gel breakage process, quantified by reduced length of the pressure wave-front zone. Ultimately, axial stress localization allows flow in longer pipe segments, albeit with a concomitant time delay. Viscous behavior and yielding degradation behavior are shown to account for upward and downward concavity in transient axial pressure profiles, respectively. Overall, a unique synergy between gel compressibility and gel degradation is revealed. Deformation-coupled interaction between compressibility and degradation allows pressure propagation and subsequent sustained flow through a gel material which is otherwise immobile in the incompressible case.

  20. Formation and subdivision of deformation structures during plastic deformation

    Jakobsen, B.; Poulsen, H.F.; Lienert, U.;


    During plastic deformation of metals and alloys, dislocations arrange in ordered patterns. How and when these self-organization processes take place have remained elusive, because in situ observations have not been feasible. We present an x-ray diffraction method that provided data on the dynamics...... of individual, deeply embedded dislocation structures. During tensile deformation of pure copper, dislocation-free regions were identified. They showed an unexpected intermittent dynamics, for example, appearing and disappearing with proceeding deformation and even displaying transient splitting behavior....... Insight into these processes is relevant for an understanding of the strength and work-hardening of deformed materials....

  1. 变工况下周向弯曲风扇叶顶涡声特性%Research of Aerodynamic Noise Source in Tip Region of Axial Fans with Circumferential Skewed Blades at Off-Design Conditions

    金光远; 欧阳华; 胡彬彬; 吴亚东; 杜朝辉


    Aerodynamic noise source generated by tip leakage flow in circumferential skewed axial fans was studied by CFD simulation and experiments under off-design conditions. Relationship between tip leakage flow and aerodynamic noise was analyzed based on vortex-sound theory of low speed homentropic flow. Synergy between acoustic source and tip leakage vortex was discussed. Pressure test on casing wall and acoustic far field test were conducted to find how the different circumferential skewed direction control acoustic characteristics. The results show that the acoustic source generated by tip leakage vortex of circumferential skewed blades is an important noise source under off-design conditions. The angle between velocity vector and vortex vector controls the strength and the distribution of the acoustic source in tip clearance region. The acoustic source in tip clearance region is related with the acoustic far field under off-design conditions.%采用计算流体力学数值方法研究变工况下周向弯曲低压轴流风扇的叶顶泄漏流动特性,结合涡声理论分析泄漏涡与声源的协同特性,分析叶片不同周向弯曲方向对协同性的影响,并通过近场机匣壁面动态压力测量和远场声学测量,验证叶片周向弯曲方向对近远场声学特性的控制规律.研究表明,泄漏涡声源是周向弯曲叶轮小流量工况下的重要声源,速度矢量与涡矢量的夹角值控制叶顶区域声源强度和分布.近远场实验结果表明,泄漏涡声源与远场声学关系密切.

  2. Numerical Investigation of Influence of Tangent Pitch and Slanting Flow of Guide Vanes on the Axial Compressor Stage Parameters

    D. V. Arkhipov


    Full Text Available The flow redistribution in the axial stage through the stator axis blade deformation can create favorable conditions for raising stage efficiency and combined actions for axial compressor elements especially in ambient conditions. For this purpose, the axis deformation impact on the gas-dynamic stability margin and the coefficient of efficiency of axial compressor has been numerically investigated.The influence of guide vane (GV axis was considered with invariable rotor blades and different variants of stator. The GV axis form was changed on the arc of a circle in the range of ± 15% guide vane height in circumferential direction and in the axial direction in the range ± 10% of guide vane height, increments ± 2.5%.As an object, for investigation was chosen a numerical 3D model of transonic stage of axial compressor with the following values of basic parameters: circumferential speed in the rotor blade trips of 345 m/s, relative diameter of the hub being 0.7, and coefficient of discharge being 0.5. The stage was profiling by classic low Cu*r=const. Rotor and stator profiles for all variants under investigation were the same in the same radii.As to initial radial axis guide vane, the losses of total pressure in stator become substantially less throughout the height of blade in case there is a guide vane axis bending in axial direction in line of flow. Bending of the axis in the circumferential direction against the rotation leads to reducing total pressure losses especially in hub and shroud regions, and in the flow core there is no change.In future, the effects of a tangent pitch and a slanting flow can be of interest in case of the simultaneous bending in both directions, as well as when studying the influence of bending of the guide vanes, which are a part of a sector of stages and a multi-stage compressor in a wide range of operating conditions.

  3. Deformation mechanisms in experimentally deformed Boom Clay

    Desbois, Guillaume; Schuck, Bernhard; Urai, Janos


    Bulk mechanical and transport properties of reference claystones for deep disposal of radioactive waste have been investigated since many years but little is known about microscale deformation mechanisms because accessing the relevant microstructure in these soft, very fine-grained, low permeable and low porous materials remains difficult. Recent development of ion beam polishing methods to prepare high quality damage free surfaces for scanning electron microscope (SEM) is opening new fields of microstructural investigation in claystones towards a better understanding of the deformation behavior transitional between rocks and soils. We present results of Boom Clay deformed in a triaxial cell in a consolidated - undrained test at a confining pressure of 0.375 MPa (i.e. close to natural value), with σ1 perpendicular to the bedding. Experiments stopped at 20 % strain. As a first approximation, the plasticity of the sample can be described by a Mohr-Coulomb type failure envelope with a coefficient of cohesion C = 0.117 MPa and an internal friction angle ϕ = 18.7°. After deformation test, the bulk sample shows a shear zone at an angle of about 35° from the vertical with an offset of about 5 mm. We used the "Lamipeel" method that allows producing a permanent absolutely plane and large size etched micro relief-replica in order to localize and to document the shear zone at the scale of the deformed core. High-resolution imaging of microstructures was mostly done by using the BIB-SEM method on key-regions identified after the "Lamipeel" method. Detailed BIB-SEM investigations of shear zones show the following: the boundaries between the shear zone and the host rock are sharp, clay aggregates and clastic grains are strongly reoriented parallel to the shear direction, and the porosity is significantly reduced in the shear zone and the grain size is smaller in the shear zone than in the host rock but there is no evidence for broken grains. Comparison of microstructures

  4. Flow and deformation of the capillary glycocalyx in the wake of a leukocyte

    Damiano, Edward R.; Stace, Thomas M.


    An analysis is presented of the axisymmetric axial and radial flow and deformation fields throughout the endothelial-cell glycocalyx surface layer in the wake region behind a leukocyte moving steadily through a capillary. The glycocalyx, modeled as a thin poroelastic surface layer lining the capillary wall, is assumed to consist of a binary mixture of a linearly viscous fluid constituent and an isotropic, highly compressible, linearly elastic solid constituent having a vanishingly small solid-volume fraction. Invoking the asymptotic approximations of lubrication theory in a frame of reference translating with the leukocyte, closed-form solutions are obtained to the leading-order boundary-value problems governing the axial and radial flow and deformation fields throughout the glycocalyx as well as the axial and radial flow fields throughout the free capillary lumen within the wake. A simple asymptotic expression is obtained for the length lchar of the wake region in terms of the translational speed U0 of the leukocyte, and the equilibrium thickness h0, permeability k0, and aggregate elastic modulus HA of the glycocalyx. The predicted wake length, as seen from an observer moving in a reference frame attached to the leukocyte, is consistent with the recovery time predicted from a one-dimensional analysis of glycocalyx deformation through a quiescent inviscid fluid. The two-dimensional fluid dynamical analysis presented here thus provides the appropriate relationships for extracting estimates of the mechanoelectrochemical properties of the glycocalyx from physiologically realistic constitutive models developed under simplified one-dimensional flow regimes. The directly measurable quantities lchar,U0, and h0, which are obtainable from in vivo observations of the wake region behind a leukocyte moving steadily through a capillary, can therefore be connected, through the results of this analysis, to estimates of the mechanoelectrochemical properties of the glycocalyx on

  5. Applicability of the laws of elasticity for the determination of the elastic-region length in the deformation zone during cold rolling

    Garber, E. A.; Shalaevskii, D. L.; Kozhevnikova, I. A.; Traino, A. I.


    The errors of calculating the energy-force parameters of cold rolling are analyzed. They appear because of the assumption of the classic rolling theory about the applicability of the Hertz formula, which is known in the theory of elasticity, to the calculation of the elastic-region length in the deformation zone. The Hertz formula, which is used to calculate the half-width of the contact area between a fixed cylinder and a plane that bounds an elastic half-space, is shown not to take into account the following factors that are characteristic and important for the roll-strip contact: the cold working of the strip, the strip thickness, the rotation of rolls accompanied by sliding friction, and the wear that decreases the initial roll roughness (i.e., changes in the friction coefficient). A method is proposed for taking into account these factors in the calculation of the energy-force parameters of cold rolling; it is based on the statistical processing of the parameters that are measured in operating mills and are present in the databases of their process control systems. The application of this method decreases the errors of calculating the rolling forces by 35 40% and refines some laws of the state of stress in a rolled strip.

  6. GPS-derived ground deformation (2005-2014) within the Gulf of Mexico region referred to a stable Gulf of Mexico reference frame

    Yang, L.; Yu, J.; Wang, G.


    This study investigates current ground deformation derived from the GPS geodesy infrastructure in the Gulf of Mexico region. The positions and velocity vectors of 161 continuous GPS (CGPS) stations are presented with respect to a newly established local reference frame, the Stable Gulf of Mexico Reference Frame (SGOMRF). Thirteen long-term ( > 5 years) CGPS are used to realize the local reference frame. The root mean square (RMS) of the velocities of the 13 SGOMRF reference stations achieves 0.2 mm yr -1 in the horizontal and 0.3 mm yr -1 in the vertical directions. GPS observations presented in this study indicate significant land subsidence in the coastal area of southeastern Louisiana, the greater Houston metropolitan area, and two cities in Mexico (Aguascalientes and Mexico City). The most rapid subsidence is recorded at the Mexico City International airport, which is up to 26.6 cm yr -1 (2008-2014). Significant spatial variation of subsidence rates is observed in both Mexico City and the Houston area. The overall subsidence rate in the Houston area is decreasing. The subsidence rate in southeastern Louisiana is relatively smaller (4.0-6.0 mm yr -1 ) but tends to be steady over time. This poses a potential threat to the safety of coastal infrastructure in the long-term.

  7. GPS-derived ground deformation (2005-2014) within the Gulf of Mexico region referred to a stable Gulf of Mexico reference frame

    Yu, Jiangbo; Wang, Guoquan


    This study investigates current ground deformation derived from the GPS geodesy infrastructure in the Gulf of Mexico region. The positions and velocity vectors of 161 continuous GPS (CGPS) stations are presented with respect to a newly established local reference frame, the Stable Gulf of Mexico Reference Frame (SGOMRF). Thirteen long-term (> 5 years) CGPS are used to realize the local reference frame. The root mean square (RMS) of the velocities of the 13 SGOMRF reference stations achieves 0.2 mm yr-1 in the horizontal and 0.3 mm yr-1 in the vertical directions. GPS observations presented in this study indicate significant land subsidence in the coastal area of southeastern Louisiana, the greater Houston metropolitan area, and two cities in Mexico (Aguascalientes and Mexico City). The most rapid subsidence is recorded at the Mexico City International airport, which is up to 26.6 cm yr-1 (2008-2014). Significant spatial variation of subsidence rates is observed in both Mexico City and the Houston area. The overall subsidence rate in the Houston area is decreasing. The subsidence rate in southeastern Louisiana is relatively smaller (4.0-6.0 mm yr-1) but tends to be steady over time. This poses a potential threat to the safety of coastal infrastructure in the long-term.

  8. Method to Measure Tone of Axial and Proximal Muscle


    The control of tonic muscular activity remains poorly understood. While abnormal tone is commonly assessed clinically by measuring the passive resistance of relaxed limbs1, no systems are available to study tonic muscle control in a natural, active state of antigravity support. We have developed a device (Twister) to study tonic regulation of axial and proximal muscles during active postural maintenance (i.e. postural tone). Twister rotates axial body regions relative to each other about the ...

  9. Study of axial magnetic effect

    Braguta, Victor [IHEP, Protvino, Moscow region, 142284 Russia ITEP, B. Cheremushkinskaya street 25, Moscow, 117218 (Russian Federation); School of Biomedicine, Far Eastern Federal University, Ajax 10 Building 25, Russian island, Vladivostok, 690922 (Russian Federation); Chernodub, M. N. [CNRS, Laboratoire de Mathématiques et Physique Théorique, Université François-Rabelais Tours, Fédération Denis Poisson, Parc de Grandmont, 37200 Tours, France Department of Physics and Astronomy, University of Gent, Krijgslaan 281, S9, B-9000 Gent (Belgium); School of Biomedicine, Far Eastern Federal University, Ajax 10 Building 25, Russian island, Vladivostok, 690922 (Russian Federation); Goy, V. A. [School of Natural Sciences, Far Eastern Federal University, Sukhanova street 8, Vladivostok, 690950 (Russian Federation); Landsteiner, K. [Instituto de Física Teórica UAM/CSIC, C/ Nicolás Cabrera 13-15, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Molochkov, A. V. [School of Biomedicine, Far Eastern Federal University, Ajax 10 Building 25, Russian island, Vladivostok, 690922 (Russian Federation); Ulybyshev, M. [ITEP, B. Cheremushkinskaya street 25, Moscow, 117218 Russia Institute for Theoretical Problems of Microphysics, Moscow State University, Moscow, 119899 (Russian Federation)


    The Axial Magnetic Effect manifests itself as an equilibrium energy flow of massless fermions induced by the axial (chiral) magnetic field. Here we study the Axial Magnetic Effect in the quenched SU(2) lattice gauge theory with massless overlap fermions at finite temperature. We numerically observe that in the low-temperature hadron phase the effect is absent due to the quark confinement. In the high-temperature deconfinement phase the energy flow is an increasing function of the temperature which reaches the predicted asymptotic T{sup 2} behavior at high temperatures. We find, however, that energy flow is about one order of magnitude lower compared to a theoretical prediction.

  10. Axial clamp for nuclear reactor head penetration conoseal joints

    Hackley, T.A.


    A method is described for forming a sealed coupling between two bodies, each body presenting an annular abutment surface. The respective bodies are arranged so that their respective annular abutment surfaces are axially adjacent one another, defining a space therebetween, wherein a deformable gasket is disposed within the space. The method comprises: providing one of the bodies with an annular projection; providing the other body with threads for receiving an annular locknut which can be tightened to bear against the annular projection of the one body; applying an external axial forced to the bodies for compressing the abutment surfaces together against the gasket to form a seal between the bodies; immobilizing the bodies relative to one another while the external force is being applied to the bodies by hand-tightening an annular locknut via the threads of the other body until the locknut abuts the annular projection of the one body, substantially preventing relative axial movement between the bodies when the external axial force is withdrawn; and withdrawing the external axial force applied to the bodies, leaving the two bodies coupled together via the seal.

  11. Crustal deformation rates in Assam Valley, Shillong Plateau, Eastern Himalaya, and Indo-Burmese region from 11 years (2002-2013) of GPS measurements

    Barman, Prakash; Jade, Sridevi; Shrungeshwara, T. S.; Kumar, Ashok; Bhattacharyya, Sanjeev; Ray, Jagat Dwipendra; Jagannathan, Saigeetha; Jamir, Wangshi Menla


    The present study reports the contemporary deformation of the tectonically complex northeast India using 11 years (2002-2013) of GPS observations. The central Shillong Plateau and few sites north of Plateau located in Assam Valley behave like a rigid block with 7 mm/year India-fixed southward velocity. The Euler pole of rotation of this central Shillong Plateau-Assam Valley (SH-AS) block is estimated to be at -25.1° ± 0.2°N, -97.8° ± 1.8°E with an angular velocity of 0.533° ± 0.10° Myr-1 relative to India-fixed reference frame. Kopili fault located between Shillong Plateau and Mikir massif records a dextral slip of 4.7 ± 1.3 mm/year with a locking depth of 10.2 ± 1.4 km indicating the fragmentation of Assam Valley across the fault. Presently, western edge of Mikir massif appears to be locked to Assam block indicating strain accumulation in this region. First-order elastic dislocation modelling of the GPS velocities estimates a slip rate of 16 mm/year along the Main Himalayan Thrust in Eastern Himalaya which is locked over a width of 130 km from the surface to a depth of 17 km with underthrusting Indian plate. Around 9 mm/year arc-normal convergence is accommodated in Lesser Himalaya just south of Main Central Thrust indicating high strain accumulation. Out of 36 mm/year (SSE) India-Sunda plate motion, about 16 mm/year motion is accommodated in Indo-Burmese Fold and Thrust Belt, both as normal convergence ( 6 mm/year) and active slip ( 7-11 mm/year) in this region.

  12. Deformation in nanocrystalline metals

    Helena Van Swygenhoven


    Full Text Available It is now possible to synthesize polycrystalline metals made up of grains that average less than 100 nm in size. Such nanocrystalline metals contain a significant volume fraction of interfacial regions separated by nearly perfect crystals. The small sizes involved limit the conventional operation of dislocation sources and thus a fundamental question arises: how do these materials deform plastically? We review the current views on deformation mechanisms in nanocrystalline, face-centered cubic metals based on insights gained by atomistic computer simulations. These insights are discussed with reference to recent striking experimental observations that can be compared with predictions made by the simulations.

  13. Some specifics of influence of pore pressure on physical properties of deformable rocks

    Sobolev, G. A.; Stakhovskaya, Z. I.; Mikayelyan, A. O.


    A study was made of a range of problems related to the physical and mechanical properties of limestones from the region of the Ingura hydroelectric powerplant under hydrostatic pore pressure with additional axial pressure. The purpose was to estimate the significance and effect of pore pressure on physical properties in rocks as a function of the stressed state under conditions of hydrostatic pressure and hydrostatic pressure with additional axial loading. The P wave velocity, resistivity and longitudinal deformation were measured under pressure with specimens which had been carefully dried and saturated under vacuum conditions with a 2 n solution of NaCl. Cyclical variations of pore pressure were found to cause compaction of the rock. Cyclical variations of pore pressure under complex stress conditions facilitate fracture and strength loss of the rock.

  14. Deformation microstructures

    Hansen, N.; Huang, X.; Hughes, D.A.


    Microstructural characterization and modeling has shown that a variety of metals deformed by different thermomechanical processes follows a general path of grain subdivision, by dislocation boundaries and high angle boundaries. This subdivision has been observed to very small structural scales...... of the order of 10 nm, produced by deformation under large sliding loads. Limits to the evolution of microstructural parameters during monotonic loading have been investigated based on a characterization by transmission electron microscopy. Such limits have been observed at an equivalent strain of about 10...

  15. [Biomechanical properties (compressive strength and compressive pressure at break) of hyaline cartilage under axial load].

    Spahn, G; Wittig, R


    Explanations concerning the physical properties of hyaline cartilage are different. It was the intention of this study to determine the material parameters of hyaline cartilage under axial load (elasticity, plasticity, elasticity and module pressure stress to break). Specimens from the medial femoral condyle (chondro-cortical ships) from adult female domestic pigs (n=28) were used for the experiments. The specimens were completely embedded in plaster to minimize shearing. Axial load was carried out by an universal mechanical testing machine (Zwick Z2.5/TS1S, Ulm, Germany) to determine elastic and plastic deformation and pressure stress to break. Axial load up to 5 MPa produces an almost elastic deformation, an increasing axial load results in a plastic deformation. In the range of 3 to 5 MPa the principle of Hooke is valid. The elasticity module amounted to 39.2 +/- 11.9 N/mm(2), determined under 3.8 MPa axial load. An axial load of 25.8 +/- 5.2 MPa (sigma max ) causes a break of cartilage. A strong correlation between break resistance and thickness of the chondral slice (r=0.71; p .05) was observed. The low module of chondral elasticity characterizes this tissue as "soft". Moderate axial load causes an ideal elastic, higher axial load a plastic deformation. The medium pressure to break to amounted 25.8 MPa. The medium pressure to break of 25.8 MPa is comparable with the forces produced by an unrestrained limited downfall from a height of 4.3 m. It must be concluded that isolated chondral fractures are rare consequences of a trauma as long as accompanying ligamentous or osseous damages are not found.

  16. Active axial spondyloarthritis: potential role of certolizumab pegol

    Ranatunga S


    Full Text Available Sriya Ranatunga, Anne V Miller Department of Internal Medicine, Southern Illinois University School of Medicine, Springfield, IL, USA Abstract: The axial spondyloarthropathies are a group of chronic inflammatory diseases that predominantly affect the axial joints. This group includes ankylosing spondylitis and nonradiographic axial spondyloarthropathy. While the pathogenesis of axial spondyloarthropathies is not clear, immunologically active tissues primarily include the entheses, ie, the areas where ligaments, tendons, and joint capsules attach to bone and to the annulus fibrosis at the vertebrae. One of the major mediators of the immune response in this group of diseases is tumor necrosis factor-alpha (TNFα. Blockade of TNFα results in reduced vascularity and inflammatory cell infiltration in the synovial tissues of affected joints. Certolizumab pegol (CZP is an Fc-free, PEGylated anti-TNFα monoclonal antibody. CZP has unique properties that differ from other available TNFα inhibitors by virtue of its lack of an Fc region, which minimizes potential Fc-mediated effects, and its PEGylation, which improves drug pharmacokinetics and bioavailability. It has been shown in clinical trials that CZP improves patient outcomes and reduces inflammation in the sacroiliac joints and spine in both ankylosing spondylitis and nonradiographic axial spondyloarthropathies. These data support CZP as a treatment option for axial spondyloarthropathies. Keywords: axial spondyloarthropathy, certolizumab pegol, anti-tumor necrosis factor-alpha, therapy

  17. Dissipative axial inflation

    Notari, Alessio; Tywoniuk, Konrad


    We analyze in detail the background cosmological evolution of a scalar field coupled to a massless abelian gauge field through an axial term phi/fγ F ~F, such as in the case of an axion. Gauge fields in this case are known to experience tachyonic growth and therefore can backreact on the background as an effective dissipation into radiation energy density ρR, which can lead to inflation without the need of a flat potential. We analyze the system, for momenta k smaller than the cutoff fγ, including the backreaction numerically. We consider the evolution from a given static initial condition and explicitly show that, if fγ is smaller than the field excursion phi0 by about a factor of at least Script O (20), there is a friction effect which turns on before the field can fall down and which can then lead to a very long stage of inflation with a generic potential. In addition we find superimposed oscillations, which would get imprinted on any kind of perturbations, scalars and tensors. Such oscillations have a period of 4-5 efolds and an amplitude which is typically less than a few percent and decreases linearly with fγ. We also stress that the curvature perturbation on uniform density slices should be sensitive to slow-roll parameters related to ρR rather than dot phi2/2 and we discuss the existence of friction terms acting on the perturbations, although we postpone a calculation of the power spectrum and of non-gaussianity to future work and we simply define and compute suitable slow roll parameters. Finally we stress that this scenario may be realized in the axion case, if the coupling 1/fγ to U(1) (photons) is much larger than the coupling 1/fG to non-abelian gauge fields (gluons), since the latter sets the range of the potential and therefore the maximal allowed phi0~ fG.

  18. Haglund's Deformity

    ... to follow the surgeon’s instructions for postsurgical care. Prevention To help prevent a recurrence of Haglund’s deformity: wear appropriate shoes; avoid shoes with a rigid heel back use arch supports or orthotic devices perform stretching exercises to prevent the Achilles tendon from tightening ...

  19. Complex-mode Galerkin approach in transverse vibration of an axially accelerating viscoelastic string

    ZHANG Neng-hui; WANG Jian-jun; CHENG Chang-jun


    Under the consideration of harmonic fluctuations of initial tension and axially velocity, a nonlinear governing equation for transverse vibration of an axially accelerating string is set up by using the equation of motion for a 3-dimensional deformable body with initial stresses. The Kelvin model is used to describe viscoelastic behaviors of the material. The basis function of the complex-mode Galerkin method for axially accelerating nonlinear strings is constructed by using the modal function of linear moving strings with constant axially transport velocity. By the constructed basis functions, the application of the complex-mode Galerkin method in nonlinear vibration analysis of an axially accelerating viscoelastic string is investigated. Numerical results show that the convergence velocity of the complex-mode Galerkin method is higher than that of the real-mode Galerkin method for a variable coefficient gyroscopic system.

  20. Evaluation of various Deformable Image Registrations for Point and Volume Variations

    Han, Su Chul; Park, Seungwoo; Lee, Soon Sung; Jung, Haijo; Kim, Mi-Sook; Yoo, Hyung Jun; Ji, Young Hoon; Yi, Chul Young; Kim, Kum Bae


    The accuracy of deformable image registration (DIR) has a significant dosimetric impact in radiation treatment planning. We evaluated accuracy of various DIR algorithms using variations of the deformation point and volume. The reference image (Iref) and volume (Vref) was first generated with virtual deformation QA software (ImSimQA, Oncology System Limited, UK). We deformed Iref with axial movement of deformation point and Vref depending on the types of deformation that are the deformation1 is to increase the Vref (relaxation) and the deformation 2 is to decrease . The deformed image (Idef) and volume (Vdef) acquired by ImSimQA software were inversely deformed to Iref and Vref using DIR algorithms. As a result, we acquired deformed image (Iid) from Idef and volume (Vid) from Vdef. The DIR algorithms were the Horn Schunk optical flow (HS), Iterative Optical Flow (IOF), Modified Demons (MD) and Fast Demons (FD) with the Deformable Image Registration and Adaptive Radiotherapy Toolkit (DIRART) of MATLAB. The imag...

  1. Constraining the Late Mesozoic and Early Tertiary Tectonic Evolution of Southern Mexico: Structure and Deformation History of the Tierra Caliente Region.

    Cabral-Cano; Draper; Lang; Harrison


    We analyze the structure and assess the deformation history of the Tierra Caliente Metamorphic Complex (TCMC) of southern Mexico, where Laramide accretion of exotic terranes is in debate. The TCMC consists of a south-plunging antiform fault that is bounded on both its eastern and western flanks. Tierra Caliente Metamorphic Complex rocks show at least two phases of compressional deformation. The first and most prominent records a mean tectonic transport direction of 068 degrees. This phase is responsible for east-verging asymmetrical folding and thrusting of both metamorphic and superjacent sedimentary rocks. The second phase has an average transport direction of 232 degrees and is restricted to the western portion of the TCMC. A third phase is responsible for normal faulting. Lack of discernible deformation before Late Cretaceous time indicates that the main deformation phase is coincident with Laramide orogenesis elsewhere in the North American Cordillera. The stratigraphy, structure, and deformational history of the TCMC do not require accretion of exotic terranes. We explain the Mesozoic tectonostratigraphic evolution of the TCMC in terms of deposition and deformation of Mesozoic volcanic and sedimentary strata over the attenuated continental crust of the North American plate.

  2. Quasi-static compression of electric resistance welded mild steel tubes with axial gradient-distributed microstructures

    Yao, Shengjie; Sun, Lei; Ma, Xudong [Harbin Institute of Technology, Weihai (China)


    This paper presents the deformation behavior and crash worthiness of electric resistance welded mild steel tubes with axial gradient microstructures in quasi-static compression. Three sets of tubes were prepared, and regions of each tube were Induction heated and directly quenched (IH-DQ). The effect of the length to diameter (L/D) ratio, and length of the IH-DQ region on crushing characteristics was investigated, and compared with untreated tubes. The compression tests revealed that improved energy absorption can be obtained in IHDQ tubes if the collapse is controlled by the formation of a concertina buckling mode. However, there was a tendency to produce mixed or Euler buckling modes as the ratio of L/D increased. Meanwhile, the results of the crush experiments and the FEM models showed that the heat-treatment process should be precisely controlled to produce the correct type of microstructure, and circumferential uniformity of microstructure distribution.

  3. A new classification for 'Pistol Grip Deformity'. Correlation between the severity of the deformity and the grade of osteoarthritis of the hip

    Ipach, Ingmar; Mittag, F.; Sachsenmaier, S.; Kluba, T. [Tuebingen Univ. (Germany). Dept. of Orthopaedic Surgery; Heinrich, P. [Klinikum rechts der Isar der Technischen Univ. Muenchen (Germany). Inst. fuer Medizinische Statistik und Epidemiologie


    Purpose: Two types of femoroacetabular impingement (FAI) are described as reasons for the early development of osteoarthritis of the hip. Cam impingement develops from contact between an abnormal head-neck junction and the acetabular rim. Pincer impingement is characterized by local or general overcoverage of the femoral head by the acetabular rim. Both forms might cause early osteoarthritis of the hip. A decreased head/neck offset has been recognized on AP pelvic views and labeled as 'pistol grip deformity'. The aim of the study was to develop a classification for this deformity with regard to the stage of osteoarthritis of the hip. Materials and Methods: 76 pelvic and axial views were analyzed for alpha angle and head ratio. 22 of them had a normal shape in the head-neck region and no osteoarthritis signs, 27 had a 'pistol grip deformity' and osteoarthritis I and 27 had a 'pistol grip deformity' and osteoarthritis II -IV . The CART method was used to develop a classification. Results: There was a statistically significant correlation between alpha angle and head ratio. A statistically significant difference in alpha angle and head ratio was seen between the three groups. Using the CART method, we developed a three-step classification system for the 'pistol grip deformity' with very high accuracy. This deformity was aggravated by increasing age. Conclusion: Using this model it is possible to differentiate between normal shapes of the head-neck junction and different severities of the pistol grip deformity. (orig.)

  4. Axial Current and Noether Charge

    Mahato, Prasanta


    A decade ago, a Lagrangian density has been proposed by the author where only the local symmetries of the Lorentz subgroup of (A)ds group is retained. This formalism has been found to produce some results encompassing that of standard Einstein-Hilbert formalism. In the present article, the conserved axial vector matter currents, constructed in some earlier paper, have been found to be a result of Noether's theorem. PACS: 04.20.Fy, 04.20.Cv, 11.40.-q Keywords: Torsion, Axial Current, Noether's Theorem

  5. Axial dispersion in flowing red blood cell suspensions

    Podgorski, Thomas; Losserand, Sylvain; Coupier, Gwennou


    A key parameter in blood microcirculation is the transit time of red blood cells (RBCs) through an organ, which can influence the efficiency of gas exchange and oxygen availability. A large dispersion of this transit time is observed in vivo and is partly due to the axial dispersion in the flowing suspension. In the classic Taylor-Aris example of a solute flowing in a tube, the combination of molecular diffusion and parabolic velocity profile leads to enhanced axial dispersion. In suspensions of non-Brownian deformable bodies such as RBCs, axial dispersion is governed by a combination of shear induced migration and shear-induced diffusion arising from hydrodynamic interactions. We revisit this problem in the case of RBC pulses flowing in a microchannel and show that the axial dispersion of the pulse eventually saturates with a final extension that depends directly on RBC mechanical properties. The result is especially interesting in the dilute limit since the final pulse length depends only on the channel width, exponent of the migration law and dimensionless migration velocity. In continuous flow, the dispersion of transit times is the result of complex cell-cell and cell-wall interactions and is strongy influenced by the polydispersity of the blood sample. The authors acknowledge support from LabEx TEC21 and CNES.

  6. Numerical modeling of land subsidence due to groundwater withdrawal in Aguascalientes Valley using regional coefficients of deformation determined by InSAR analysis.

    Pacheco, J.; Cabral, E.; Wdowinski, S.; Hernandez-Marin, M.; Ortíz, J. Á.; Solano Rojas, D. E.; Oliver-Cabrera, T.


    Land subsidence due to groundwater over-exploitation is a deformation process affecting many cities around the world. This type of subsidence develops gradual vertical deformations reaching only a few centimeters per year, but can affect large areas. Consequently, inhabitants of subsiding areas are not aware of the process until others effects are observed, such as ground surface faulting, damage to building, or changes in the natural superficial drain. In order to mitigate and forecast subsidence consequences, it is useful to conduct numerical modeling of the subsidence process. Modeling the subsidence includes the following three basic tasks: a) Delimitation of the shape of the deforming body; b) Determination of the forces that are causing the deformations; and c) Determination of the mechanical properties of the deforming body according with an accepted rheological model. In the case of a land subsidence process, the deforming body is the aquifer system that is being drained. Usually, stratigraphic information from pumping wells, and other geophysical data are used to define the boundaries and shape of the aquifer system. The deformation governing forces, or stresses, can be calculated using the theory of "effective stress". Mechanical properties are usually determined with laboratory testing of samples from shallow strata, because the determination of these properties in samples from the deepest strata is economically or technically unviable. Consequently, the results of the numerical modeling do not necessarily match the observed subsidence evolution and ground faulting. We present in this work numerical simulation results of the land subsiding of the Valley of Aguascalientes, Mexico. Two analyses for the same subsiding area are presented. In the first of them, we used the mechanical properties of only the shallow strata, whereas in the second analysis we used "macroscopic" mechanical properties data determined for the whole aquifer system using In

  7. Structural characterization of the internal domain of Paraguai Belt, in the Cangas region, south central portion of Mato Grosso, Brazil

    Bruno de Siqueira Costa

    Full Text Available The structural study of rocks in the district of Cangas showed the identification of three phases of deformation for the Cuiabá Group in this region. The main structure oriented 120/27 is related to the first phase of deformation defined by a slate cleavage, parallel to the bedding and to the axial plane of recumbent folds. In the early stages of this phase a family of quartz veins (V1 was generated, arranged parallel to the structures of this phase of deformation, being all almost deformed. The second phase of deformation formed a crenulation cleavage (Sn+1, axial plane of opened to gentle and asymmetric normal folds, with preferential orientation 110/68. The third phase of deformation is represented by a set of centimetric to decametric scale fractures and faults with metric slip that cut all previous structures, with orientations 35/82. Related to this phase of deformation occurs a second family of quartz veins (V2, which fills the fractures related to Dn+2 and may or may not be carrying gold mineralization.

  8. Axial compression physical testing of traditional and bird beak SHS T-joints

    陈誉; 王江


    The static tests of nine traditional and bird beak square hollow structure (SHS) T-joints with differentβ values and connection types under axial compression at brace end were carried out. Experimental test schemes, failure modes of specimens, jack load−vertical displacement curves, jack load−deformation of chord and strain intensity distribution curves of joints were presented. The effects ofβ and connection types on axial compression property of joints were studied. The results show that the ultimate axial compression capacity of common bird beak SHS T-joints and diamond bird beak SHS T-joints is larger than that of traditional SHS T-joint specimens with big values ofβ. The ultimate axial compression capacity of diamond bird beak SHS T-joints is larger than that of common bird beak SHS T-joints. Asβ increases, the increase of the ultimate axial compression capacity of diamond bird beak SHS T-joints over that of common bird beak joints grows. The ultimate axial compression capacity and the initial axial stiffness of all kinds of joints increase asβincreases, and the initial axial stiffness of the diamond bird beak SHS T-joints is the largest. The ductilities of common bird beak and diamond bird beak SHS T-joints increase asβ increases, but the ductility of the traditional SHS T-joints decreases asβ increases.

  9. Utilizing multiple scale models to improve predictions of extra-axial hemorrhage in the immature piglet.

    Scott, Gregory G; Margulies, Susan S; Coats, Brittany


    Traumatic brain injury (TBI) is a leading cause of death and disability in the USA. To help understand and better predict TBI, researchers have developed complex finite element (FE) models of the head which incorporate many biological structures such as scalp, skull, meninges, brain (with gray/white matter differentiation), and vasculature. However, most models drastically simplify the membranes and substructures between the pia and arachnoid membranes. We hypothesize that substructures in the pia-arachnoid complex (PAC) contribute substantially to brain deformation following head rotation, and that when included in FE models accuracy of extra-axial hemorrhage prediction improves. To test these hypotheses, microscale FE models of the PAC were developed to span the variability of PAC substructure anatomy and regional density. The constitutive response of these models were then integrated into an existing macroscale FE model of the immature piglet brain to identify changes in cortical stress distribution and predictions of extra-axial hemorrhage (EAH). Incorporating regional variability of PAC substructures substantially altered the distribution of principal stress on the cortical surface of the brain compared to a uniform representation of the PAC. Simulations of 24 non-impact rapid head rotations in an immature piglet animal model resulted in improved accuracy of EAH prediction (to 94 % sensitivity, 100 % specificity), as well as a high accuracy in regional hemorrhage prediction (to 82-100 % sensitivity, 100 % specificity). We conclude that including a biofidelic PAC substructure variability in FE models of the head is essential for improved predictions of hemorrhage at the brain/skull interface.

  10. Axial residual stresses in boron fibers

    Behrendt, D. R.


    A method of measuring axial residual stresses in boron fibers is presented. With this method, the axial residual stress distribution as a function of radius is determined from the fiber surface to the core including the average residual stress in the core. Such measurements on boron on tungsten (B/W) fibers show that the residual stresses for 102, 142, 203, and 366 micron diam fibers are similar, being compressive at the surface and changing monotonically to a region of tensile stress within the boron. At approximately 25% of the original radius, the stress reaches a maximum tensile stress of about 860 MN sq m and then decreases to a compressive stress near the tungsten boride core. Data are presented for 203-micron diam B/W fibers that show annealing above 900 C reduces the residual stresses. A comparison between 102-micron diam B/W and boron on carbon (B/C) show that the residual stresses are similar in the outer regions of the fibers, but that large differences near and in the core are observed. Fracture of boron fibers is discussed.

  11. Axially Symmetric, Spatially Homothetic Spacetimes

    Wagh, S M; Wagh, Sanjay M.; Govinder, Keshlan S.


    We show that the existence of appropriate spatial homothetic Killing vectors is directly related to the separability of the metric functions for axially symmetric spacetimes. The density profile for such spacetimes is (spatially) arbitrary and admits any equation of state for the matter in the spacetime. When used for studying axisymmetric gravitational collapse, such solutions do not result in a locally naked singularity.

  12. Thermophoresis of Axially Symmetric Bodies


    Sweden Abstract. Thermophoresis of axially symmetric bodies is investigated to first order in the Knudsen-mimber, Kn. The study is made in the limit...derived. Asymptotic solutions are studied. INTRODUCTION Thermophoresis as a phenomenon has been known for a long time, and several authors have approached

  13. Axial structure of the nucleon

    Veronique Bernard; Latifa Elouadrhiri; Ulf-G Meissner


    We review the current status of experimental and theoretical understanding of the axial nucleon structure at low and moderate energies. Topics considered include (quasi)elastic (anti)neutrino-nucleon scattering, charged pion electroproduction off nucleons and ordinary as well as radiative muon capture on the proton.

  14. Method to measure tone of axial and proximal muscle.

    Gurfinkel, Victor S; Cacciatore, Timothy W; Cordo, Paul J; Horak, Fay B


    The control of tonic muscular activity remains poorly understood. While abnormal tone is commonly assessed clinically by measuring the passive resistance of relaxed limbs, no systems are available to study tonic muscle control in a natural, active state of antigravity support. We have developed a device (Twister) to study tonic regulation of axial and proximal muscles during active postural maintenance (i.e. postural tone). Twister rotates axial body regions relative to each other about the vertical axis during stance, so as to twist the neck, trunk or hip regions. This twisting imposes length changes on axial muscles without changing the body's relationship to gravity. Because Twister does not provide postural support, tone must be regulated to counteract gravitational torques. We quantify this tonic regulation by the restive torque to twisting, which reflects the state of all muscles undergoing length changes, as well as by electromyography of relevant muscles. Because tone is characterized by long-lasting low-level muscle activity, tonic control is studied with slow movements that produce "tonic" changes in muscle length, without evoking fast "phasic" responses. Twister can be reconfigured to study various aspects of muscle tone, such as co-contraction, tonic modulation to postural changes, tonic interactions across body segments, as well as perceptual thresholds to slow axial rotation. Twister can also be used to provide a quantitative measurement of the effects of disease on axial and proximal postural tone and assess the efficacy of intervention.


    周喆; 秦伶俐; 黄文彬; 王红卫


    Whether the concept of effective stress and strain in elastic-plastic theory is still valid under the condition of finite deformation was mainly discussed. The uni-axial compression experiments in plane stress and plane strain states were chosen for study. In the two kinds of stress states, the stress- strain curve described by logarithm strain and rotated Kirchhoff stress matches the experiments data better than the curves defined by other stressstrain description.

  16. Optimization of axial blowers. Optimierung von Axial-Ventilatoren

    Bolte, W.


    For the optimum possible design of axial blowers, trials are evaluated in the article, which are based on the grid profile examined by N. Scholz. The computation for the pressure number and the primary degree of efficiency are shown as well as the evaluation of the effect of the Reynolds and mach number on the degree of efficiency and determination of the secondary losses. In a final example, the dimensions of a blower are computed from the data determined during the trials. (orig.).

  17. Nonaxial hexadecapole deformation effects on the fission barrier

    Kardan, A.; Nejati, S.


    Fission barrier of the heavy nucleus 250Cf is analyzed in a multi-dimensional deformation space. This space includes two quadrupole (ɛ2,γ) and three hexadecapole deformation (ɛ40,ɛ42,ɛ44) parameters. The analysis is performed within an unpaired macroscopic-microscopic approach. Special attention is given to the effects of the axial and non-axial hexadecapole deformation shapes. It is found that the inclusion of the nonaxial hexadecapole shapes does not change the fission barrier heights, so it should be sufficient to minimize the energy in only one degree of freedom in the hexadecapole space ɛ4. The role of hexadecapole deformation parameters is also discussed on the Lublin-Strasbourg drop (LSD) macroscopic and the Strutinsky shell energies.

  18. View of the Axial Field Spectrometer


    The Axial Field Spectrometer, with the vertical uranium/scintillator calorimeter and the central drift chamber retracted for service. One coil of the Open Axial Field Magnet is just visible to the right.

  19. An exact dynamic stiffness matrix for axially loaded double-beam systems

    Li Xiaobin; Xu Shuangxi; Wu Weiguo; Li Jun


    An exact dynamic stiffness method is presented in this paper to determine the natural frequencies and mode shapes of the axially loaded double-beam systems,which consist of two homogeneous and prismatic beams with a distributed spring in parallel between them.The effects of the axial force, shear deformation and rotary inertia are considered, as shown in the theoretical formulation. The dynamic stiffness influence coefficients are formulated from the governing differential equations of the axially loaded double-beam system in free vibration by using the Laplace transform method. An example is given to demonstrate the effectiveness of this method, in which ten boundary conditions are investigated and the effect of the axial force on the natural frequencies and mode shapes of the double-beam system are further discussed.

  20. [Axial spondyloarthritis and ankylosing spondylitis].

    Nordström, Dan; Kauppi, Markku


    Current classification criteria for ankylosing spondylitis do not allow diagnosis before radiographic changes are visible in sacroiliacal joints. The the new axial spondyloarthropathy (SpA) criteria include axial SpA without radiographic changes as well as established ankylosing spondylitis, recognizing them as a continuum of the same disease. This is of major importance as the burden of early SpA is comparable to that of later stage disease. Diagnosis relies on inflammatory MRI findings which is the most significant change compared to earlier criteria. Emerging data on the efficacy of tumor necrosis factor (TNF) alpha blocking therapies already in early but also in established disease have given new promising alternatives for treatment of this often very cumbersome disease, that rarely responds to classic DMARDs.

  1. Axial Spondyloarthritis: An Evolving Concept

    Nelly Ziadé


    Full Text Available Axial spondyloarthritis (AxSpA is the prototype of a family of inter-related yet heterogeneous diseases sharing common clinical and genetic manifestations: the spondyloarthritides (SpAs. The condition mainly affects the sacroiliac joints and axial skeleton, and has a clear classification scheme, wider epidemiological data, and distinct therapeutic guidelines when compared with other SpAs. However, the concept of AxSpA has not been immutable over time and has evolved tremendously on many levels over the past decades. This review identifies the evolution of the AxSpA concept at two levels. First, at the level of classification, the old classifications and rationales leading to the current Assessment of SpondyloArthritis international Society (ASAS classification are reviewed, and the advantages and drawbacks are discussed. Second, at the therapeutic level, current and future treatments are described and treatment strategies are discussed.

  2. Strain distributions and electronic property modifications in Si/Ge axial nanowire heterostructures

    Swadener, John Gregory [Los Alamos National Laboratory; Picraux, Samuel T [Los Alamos National Laboratory


    Molecular dynamics simulations were carried out for Si/Ge axial nanowire heterostructures using modified effective atom method (MEAM) potentials. A Si-Ge MEAM interatomic cross potential was developed based on available experimental data and used for these studies. The atomic distortions and strain distributions near the Si/Ge interfaces are predicted for nanowires with their axes oriented along the [111] direction. The cases of 10 and 25 nm diameter SilGe biwires and of 25 nm diameter Si/Ge/Si axial heterostructures with the Ge disc 1 nm thick were studied. Substantial distortions in the height of the atoms adjacent to the interface were found for the biwires, but not for the Ge discs. Strains as high as 3.5% were found for the Ge disc and values of 2 to 2.5% were found at the Si and Ge interfacial layers in the biwires. Deformation potential theory was used to estimate the influence of the strains on the band gap, and reductions in band gap to as small as 40% of bulk values are predicted for the Ge discs. Localized regions of increased strain and resulting energy minima were also found within the Si/Ge biwire interfaces with the larger effects on the Ge side of the interface. The regions of strain maxima near and within the interfaces are anticipated to be useful for tailoring band gaps and producing quantum confinement of carriers. These results suggest nanowire heterostructures provide greater design flexibility in band structure modification than is possible with planar layer growth.


    Yang Xiaodong; Chen Liqun


    The axially moving beams on simple supports with torsion springs are studied. The general modal functions of the axially moving beam with constant speed have been obtained from the supporting conditions. The contribution of the spring stiffness to the natural frequencies has been numerically investigated. Transverse stability is also studied for axially moving beams on simple supports with torsion springs. The method of multiple scales is applied to the partialdifferential equation governing the transverse parametric vibration. The stability boundary is derived from the solvability condition. Instability occurs if the axial speed fluctuation frequency is close to the sum of any two natural frequencies or is two fold natural frequency of the unperturbed system. It can be concluded that the spring stiffness makes both the natural frequencies and the instability regions smaller in the axial speed fluctuation frequency-amplitude plane for given mean axial speed and bending stiffness of the beam.

  4. Identification of Highly Deformed Even-Even Nuclides in the Neutron- and Proton-Rich Regions of the Nuclear Chart from the B(E2) and E2 Predictions in the Generalized Differential Equation Model

    Nayak, R C


    We identify here possible occurrence of large deformations in the neutron- and proton-rich regions of the nuclear chart from extensive predictions of the values of the reduced quadrupole transition probability B-E2 for the transition from the ground state to the first 2+ state and the corresponding excitation energy E2 of even-even nuclei in the recently developed Generalized Differential Equation model exclusively meant for these physical quantities. This is made possible from our analysis of the predicted values of these two physical quantities and the corresponding deformation parameters derived from them such as the quadrupole deformation beta-2, the ratio of beta-2 to the Weisskopf single-particle beta-2 and the intrinsic electric quadruplole moment , calculated for a large number of both known as well as hitherto unknown even-even isotopes of Oxygen to Fermium (Z=8 to 100). Our critical analysis of the resulting data convincingly support possible existence of large collectivity for the nuclides 30,32 Ne...

  5. Tooth and bone deformation: structure and material properties by ESPI

    Zaslansky, Paul; Shahar, Ron; Barak, Meir M.; Friesem, Asher A.; Weiner, Steve


    In order to understand complex-hierarchical biomaterials such as bones and teeth, it is necessary to relate their structure and mechanical-properties. We have adapted electronic speckle pattern-correlation interferometry (ESPI) to make measurements of deformation of small water-immersed specimens of teeth and bones. By combining full-field ESPI with precision mechanical loading we mapped sub-micron displacements and determined material-properties of the samples. By gradually and elastically compressing the samples, we compensate for poor S/N-ratios and displacement differences of about 100nm were reliably determined along samples just 2~3mm long. We produced stress-strain curves well within the elastic performance range of these materials under biologically relevant conditions. For human tooth-dentin, Young's modulus in inter-dental areas of the root is 40% higher than on the outer sides. For cubic equine bone samples the compression modulus of axial orientations is about double the modulus of radial and tangential orientations (20 GPa versus 10 GPa respectively). Furthermore, we measured and reproduced a surprisingly low Poisson's ratio, which averaged about 0.1. Thus the non-contact and non-destructive measurements by ESPI produce high sensitivity analyses of mechanical properties of mineralized tissues. This paves the way for mapping deformation-differences of various regions of bones, teeth and other biomaterials.

  6. Golimumab for treatment of axial spondyloarthritis.

    Rios Rodriguez, Valeria; Poddubnyy, Denis


    Axial spondyloarthritis comprises two forms: nonradiographic (nonradiographic axial spondyloarthritis) and radiographic (better known as ankylosing spondylitis), which are often considered as two stages of one disease. Historically, all currently available TNF-α inhibitors were first investigated in ankylosing spondylitis and later on in nonradiographic axial spondyloarthritis. This year, EMA has granted golimumab approval for the treatment of active nonradiographic axial spondyloarthritis based on the recently published data from the GO-AHEAD study. This article summarizes recent data on efficacy and safety of golimumab in the treatment of ankylosing spondylitis and nonradiographic axial spondyloarthritis.


    王涛; 巩若箴


    Objective:To discuss the relationship between the Chiari- Ⅰ deformity and the perioccipital foramen magnum region defor mity in imaging, clinical and pathological manifestation. Methods: Forty one cases of Chiair- Ⅰ deformity in which 28 cases had undergone MRI, 29 cases for CT, and 9 cases for both these two examinations were studied. Results: There was the tonsilla cerebelli herniation in all CT cases which had extent downward from foramen magnum, 25 to C1 bottom level, 4 down to C2 level and below. The tonsilla cerebelli as a soft mass is posterior to cervical spinal cord in magnum foramen level in all axial imaging. In 8 of 9 cases of CTM show the cervical spinal cord deformation due to tonsilla cerebelli compression. Sagittal reconstruction images show that the tonsilla cerebelli extended downward to the spinal canal from the posterior fossa. All 28 cases of MRIgroup showed wedge-shaped tonsilla herniation extending 5 ~ 8 mm down ward magnum foremen; non indicate pathologic characteristics of Chian- Ⅰ deformity. Conclusion: The cervical and medullary curvature was due to the posterior fossa invagination but not to the Chiari- Ⅰ deformity itself.

  8. SU-E-J-104: Evaluation of Accuracy for Various Deformable Image Registrations with Virtual Deformation QA Software

    Han, S; Kim, K; Kim, M; Jung, H; Ji, Y [University of Science and Technology, Daejeon (Korea, Republic of); Korea institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Choi, S; Park, S [Korea institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)


    Purpose: The accuracy of deformable image registration (DIR) has a significant dosimetric impact in radiation treatment planning. We evaluated accuracy of various DIR algorithms using virtual deformation QA software (ImSimQA, Oncology System Limited, UK). Methods: The reference image (Iref) and volume (Vref) was first generated with IMSIMQA software. We deformed Iref with axial movement of deformation point and Vref depending on the type of deformation that are the deformation1 is to increase the Vref (relaxation) and the deformation 2 is to decrease the Vref (contraction) .The deformed image (Idef) and volume (Vdef) were inversely deformed to Iref and Vref using DIR algorithms. As a Result, we acquired deformed image (Iid) and volume (Vid). The DIR algorithms were optical flow (HS, IOF) and demons (MD, FD) of the DIRART. The image similarity evaluation between Iref and Iid was calculated by Normalized Mutual Information (NMI) and Normalized Cross Correlation (NCC). The value of Dice Similarity Coefficient (DSC) was used for evaluation of volume similarity. Results: When moving distance of deformation point was 4 mm, the value of NMI was above 1.81 and NCC was above 0.99 in all DIR algorithms. Since the degree of deformation was increased, the degree of image similarity was decreased. When the Vref increased or decreased about 12%, the difference between Vref and Vid was within ±5% regardless of the type of deformation. The value of DSC was above 0.95 in deformation1 except for the MD algorithm. In case of deformation 2, that of DSC was above 0.95 in all DIR algorithms. Conclusion: The Idef and Vdef have not been completely restored to Iref and Vref and the accuracy of DIR algorithms was different depending on the degree of deformation. Hence, the performance of DIR algorithms should be verified for the desired applications.

  9. Finite deformations of an electroelastic circular cylindrical tube

    Melnikov, Andrey; Ogden, Ray W.


    In this paper the theory of nonlinear electroelasticity is used to examine deformations of a pressurized thick-walled circular cylindrical tube of soft dielectric material with closed ends and compliant electrodes on its curved boundaries. Expressions for the dependence of the pressure and reduced axial load on the deformation and a potential difference between, or uniform surface charge distributions on, the electrodes are obtained in respect of a general isotropic electroelastic energy function. To illustrate the behaviour of the tube, specific forms of energy functions accounting for different mechanical properties coupled with a deformation independent quadratic dependence on the electric field are used for numerical purposes, for a given potential difference and separately for a given charge distribution. Numerical dependences of the non-dimensional pressure and reduced axial load on the deformation are obtained for the considered energy functions. Results are then given for the thin-walled approximation as a limiting case of a thick-walled cylindrical tube without restriction on the energy function. The theory described herein provides a general basis for the detailed analysis of the electroelastic response of tubular dielectric elastomer actuators, which is illustrated for a fixed axial load in the absence of internal pressure and fixed internal pressure in the absence of an applied axial load.

  10. Deformation and fatigue behaviors of carburized automotive gear steel and predictions

    Bonglae Jo


    Full Text Available The fatigue behavior of carburized components such as automotive transmission gears is very complex due to hardness and microstructure difference, residual stresses and multi-axial stress states developed between the case and the core. In addition, automotive gears in service, commonly used in helical type, are actually subjected to complex stress conditions such as bending, torsion, and contact stress states. This study presents experimental and analytical results on deformation behavior of carburized steels, widely used in automotive gears, under cyclic stress conditions including axial and torsion loadings. Axial fatigue tests and rotating bending fatigue tests are also included. Predictions of cyclic deformation and fatigue behaviors of the carburized steel with two-layer model are compared with experimental results. The carburized steel investigated in this study exhibited cyclic softening under both axial loading and torsional loading. Predicted results with simple two-layer model for the cyclic deformation and fatigue behaviors were comparatively similar to the experimental data.

  11. In vivo dynamic deformation of the mitral valve annulus.

    Eckert, Chad E; Zubiate, Brett; Vergnat, Mathieu; Gorman, Joseph H; Gorman, Robert C; Sacks, Michael S


    Though mitral valve (MV) repair surgical procedures have increased in the United States [Gammie, J. S., et al. Ann. Thorac. Surg. 87(5):1431-1437, 2009; Nowicki, E. R., et al. Am. Heart J. 145(6):1058-1062, 2003], studies suggest that altering MV stress states may have an effect on tissue homeostasis, which could impact the long-term outcome [Accola, K. D., et al. Ann. Thorac. Surg. 79(4):1276-1283, 2005; Fasol, R., et al. Ann. Thorac. Surg. 77(6):1985-1988, 2004; Flameng, W., P. Herijgers, and K. Bogaerts. Circulation 107(12):1609-1613, 2003; Gillinov, A. M., et al. Ann. Thorac. Surg. 69(3):717-721, 2000]. Improved computational modeling that incorporates structural and geometrical data as well as cellular components has the potential to predict such changes; however, the absence of important boundary condition information limits current efforts. In this study, novel high definition in vivo annular kinematic data collected from surgically implanted sonocrystals in sheep was fit to a contiguous 3D spline based on quintic-order hermite shape functions with C(2) continuity. From the interpolated displacements, the annular axial strain and strain rate, bending, and twist along the entire annulus were calculated over the cardiac cycle. Axial strain was shown to be regionally and temporally variant with minimum and maximum values of -10 and 4%, respectively, observed. Similarly, regionally and temporally variant strain rate values, up to 100%/s contraction and 120%/s elongation, were observed. Both annular bend and twist data showed little deviation from unity with limited regional variations, indicating that most of the energy for deformation was associated with annular axial strain. The regionally and temporally variant strain/strain rate behavior of the annulus are related to the varied fibrous-muscle structure and contractile behavior of the annulus and surrounding ventricular structures, although specific details are still unavailable. With the high resolution

  12. Magnetic Barkhausen emission in lightly deformed AISI 1070 steel

    Capo Sanchez, J., E-mail: [Departamento de Fisica, Facultad de Ciencias Naturales, Universidad de Oriente, Av. Patricio Lumumba s/n, 90500 Santiago de Cuba (Cuba); Campos, M.F. de [EEIMVR-Universidade Federal Fluminense, Av. dos Trabalhadores 420, Vila Santa Cecilia, 27255-125 Volta Redonda, RJ (Brazil); Padovese, L.R. [Departamento de Engenharia Mecanica, Escola Politecnica, Universidade de Sao Paulo, Av. Prof. Mello Moraes, 2231, 05508-900 Sao Paulo (Brazil)


    The Magnetic Barkhausen Noise (MBN) technique can evaluate both micro- and macro-residual stresses, and provides indication about the relevance of contribution of these different stress components. MBN measurements were performed in AISI 1070 steel sheet samples, where different strains were applied. The Barkhausen emission is also analyzed when two different sheets, deformed and non-deformed, are evaluated together. This study is useful to understand the effect of a deformed region near the surface on MBN. The low permeability of the deformed region affects MBN, and if the deformed region is below the surface the magnetic Barkhausen signal increases. - Highlights: > Evaluated residual stresses by the magnetic Barkhausen technique. > Indication about the relevance of micro-and macro-stress components. > Magnetic Barkhausen measurements were carried out in AISI 1070 steel sheet samples. > Two different sheets, deformed and non-deformed, are evaluated together. > Magnetic Barkhausen signal increases when deformed region is below the surface.

  13. Relativistic Hartree-Fock-Bogoliubov model for deformed nuclei

    Ebran, J -P; Arteaga, D Pena; Vretenar, D


    The Relativistic Hartree-Fock-Bogoliubov model for axially deformed nuclei (RHFBz) is introduced. The model is based on an effective Lagrangian with density-dependent meson-nucleon couplings in the particle-hole channel, and the pairing part of the Gogny force is used in the pairing channel. The RHFBz quasiparticle equations are solved by expansion in the basis of a deformed harmonic oscillator. Illustrative RHFBz calculations are performed for Carbon, Neon and Magnesium isotopes. The effect of the explicitly including the pion field is investigated for binding energies, deformation parameters, and charge radii.

  14. Axial Globe Length in Congenital Ptosis.

    Takahashi, Yasuhiro; Kang, Hyera; Kakizaki, Hirohiko


    To compare axial globe length between affected and unaffected sides in patients with unilateral congenital ptosis. This prospective observational study included 37 patients (age range: 7 months to 58 years). The axial globe length, margin reflex distance-1 (MRD-1), and refractive power were measured. The axial globe length difference was calculated by subtracting the axial globe length on the unaffected side from that of the affected side. The relationships among axial globe length differences, MRD-1 on the affected sides, and patient ages were analyzed using multiple regression analysis. No significant differences were found in the axial globe length between sides (P = .677). The axial globe length difference was 0.17 ± 0.30 mm (mean ± standard deviation), and two patients (5.4%), aged 32 to 57 years, showed axial globe length more than 0.67 mm longer (corresponding to a refractive power of 2 diopters) on the affected side compared to the unaffected side. The multiple regression model between axial globe length difference, patient age, and MRD-1 on the affected sides was less appropriate (YAGL = 0.003XAGE-0.048XMRD-1 +0.112; r = 0.338; adjusted r2 = 0.062; P = .127). The cylindrical power was greater on the affected side (P = .046), although the spherical power was not different between sides (P = .657). No significant difference was identified in the axial globe length between sides, and only 5% of non-pediatric patients showed an axial globe length more than 0.67 mm longer on the affected side. Congenital ptosis may have little effect on axial globe length elongation, and the risk of axial myopia-induced anisometropic amblyopia may be low in patients with unilateral congenital ptosis. Copyright 2015, SLACK Incorporated.

  15. A general method of design of axial and radial shim coils for NMR and MRI magnets

    Bobrov, E.S.; Punchard, W.F.B.


    The paper describes a general and efficient method of design of axial and radial shim coils to correct field impurities of various harmonic orders in regions of homogeneity of high resolution Nuclear Magnetic Resonance and Magnetic Resonance Imaging magnets.

  16. An Assessment of Cumulative Axial and Torsional Fatigue in a Cobalt-Base Superalloy

    Kalluri, Sreeramesh; Bonacuse, Peter J.


    Cumulative fatigue under axial and torsional loading conditions can include both load-order (higMow and low/high) as well as load-type sequence (axial/torsional and torsional/axial) effects. Previously reported experimental studies on a cobalt-base superalloy, Haynes 188 at 538 C, addressed these effects. These studies characterized the cumulative axial and torsional fatigue behavior under high amplitude followed by low amplitude (Kalluri, S. and Bonacuse, P. J., "Cumulative Axial and Torsional Fatigue: An Investigation of Load-Type Sequance Effects," in Multiaxial Fatigue and Deformation: Testing and Prediction, ASTM STP 1387, S. Kalluri, and P. J. Bonacuse, Eds., American Society for Testing and Materials, West Conshohocken, PA, 2000, pp. 281-301) and low amplitude followed by high amplitude (Bonacuse, P. and Kalluri, S. "Sequenced Axial and Torsional Cumulative Fatigue: Low Amplitude Followed by High Amplitude Loading," Biaxial/Multiaxial Fatigue and Fracture, ESIS Publication 31, A. Carpinteri, M. De Freitas, and A. Spagnoli, Eds., Elsevier, New York, 2003, pp. 165-182) conditions. In both studies, experiments with the following four load-type sequences were performed: (a) axial/axial, (b) torsional/torsional, (c) axial/torsional, and (d) torsional/axial. In this paper, the cumulative axial and torsional fatigue data generated in the two previous studies are combined to generate a comprehensive cumulative fatigue database on both the load-order and load-type sequence effects. This comprehensive database is used to examine applicability of the Palmgren-langer-Miner linear damage rule and a nonlinear damage curve approach for Haynes 188 subjected to the load-order and load-type sequencing described above. Summations of life fractions from the experiments are compared to the predictions from both the linear and nonlinear cumulative fatigue damage approaches. The significance of load-order versus load-type sequence effects for axial and torsional loading conditions

  17. Deformation processes in orogenic wedges: New methods and application to Northwestern Washington State

    Thissen, Christopher J.

    Permanent deformation records aspects of how material moves through a tectonic environment. The methods required to measure deformation vary based on rock type, deformation process, and the geological question of interest. In this thesis we develop two new methods for measuring permanent deformation in rocks. The first method uses the autocorrelation function to measure the anisotropy present in two-dimensional photomicrographs and three-dimensional X-ray tomograms of rocks. The method returns very precise estimates for the deformation parameters and works best for materials where the deformation is recorded as a shape change of distinct fabric elements, such as grains. Our method also includes error estimates. Image analysis techniques can focus the method on specific fabric elements, such as quartz grains. The second method develops a statistical technique for measuring the symmetry in a distribution of crystal orientations, called a lattice-preferred orientation (LPO). We show that in many cases the symmetry of the LPO directly constrains the symmetry of the deformation, such axial flattening vs. pure shear vs. simple shear. In addition to quantifying the symmetry, the method uses the full crystal orientation to estimate symmetry rather than pole figures. Pole figure symmetry can often be misleading. This method works best for crystal orientations measured in samples deformed by dislocation creep, but otherwise can be used on any mineral without requiring information about slip systems. In Chapter 4 we show how deformation measurements can be used to inform regional tectonic and orogenic models in the Pacific Northwestern United States. A suite of measurements from the Olympic Mountains shows that uplift and deformation of the range is consistent with an orogenic wedge model driven by subduction of the Juan de Fuca plate, and not northward forearc migration of the Oregon block. The deformation measurements also show that deformation within the Olympic Mountains

  18. On the dynamic stability of shear deformable beams under a tensile load

    Caddemi, S.; Caliò, I.; Cannizzaro, F.


    Loss of stability of beams in a linear static context due to the action of tensile loads has been disclosed only recently in the scientific literature. However, tensile instability in the dynamic regime has been only marginally covered. Several aspects concerning the role of shear deformation on the tensile dynamic instability on continuous and discontinuous beams are still to be addressed. It may appear as a paradox, but also for the case of the universally studied Timoshenko beam model, despite its old origin, frequency-axial load diagrams in the range of negative values of the load (i.e. tensile load) has never been brought to light. In this paper, for the first time, the influence of a conservative tensile axial loads on the dynamic behaviour of the Timoshenko model, according to the Haringx theory, is assessed. It is shown that, under increasing tensile loads, regions of positive/negative fundamental frequency variations can be distinguished. In addition, the beam undergoes eigen-mode changes, from symmetric to anti-symmetric shapes, until tensile instability of divergence type is reached. As a further original contribution on the subject, taking advantage of a new closed form solution, it is shown that the same peculiarities are recovered for an axially loaded Euler-Bernoulli vibrating beam with multiple elastic sliders. This latter model can be considered as the discrete counterpart of the Timoshenko beam-column in which the internal sliders concentrate the shear deformation that in the Timoshenko model is continuously distributed. Original aspects regarding the evolution of the vibration frequencies and the relevant mode shapes with the tensile load value are highlighted.

  19. Axial Vector $Z'$ and Anomaly Cancellation

    Ismail, Ahmed; Tsao, Kuo-Hsing; Unwin, James


    Whilst the prospect of new $Z'$ gauge bosons with only axial couplings to the Standard Model (SM) fermions is widely discussed, examples of anomaly-free renormalisable models are lacking in the literature. We look to remedy this by constructing several motivated examples. Specifically, we consider axial vectors which couple universally to all SM fermions, as well as those which are generation-specific, leptophilic, and leptophobic. Anomaly cancellation typically requires the presence of new coloured and charged chiral fermions, and we argue that the masses of these new states must generally be comparable to that of the axial vector. Finally, an axial vector mediator could provide a portal between SM and hidden sector states, and we also consider the possibility that the axial vector couples to dark matter. If the dark matter relic density is set due to freeze-out via the axial vector, this strongly constrains the parameter space.

  20. Axial vector Z‧ and anomaly cancellation

    Ismail, Ahmed; Keung, Wai-Yee; Tsao, Kuo-Hsing; Unwin, James


    Whilst the prospect of new Z‧ gauge bosons with only axial couplings to the Standard Model (SM) fermions is widely discussed, examples of anomaly-free renormalisable models are lacking in the literature. We look to remedy this by constructing several motivated examples. Specifically, we consider axial vectors which couple universally to all SM fermions, as well as those which are generation-specific, leptophilic, and leptophobic. Anomaly cancellation typically requires the presence of new coloured and charged chiral fermions, and we argue that in a large class of models masses of these new states are expected to be comparable to that of the axial vector. Finally, an axial vector mediator could provide a portal between SM and hidden sector states, and we also consider the possibility that the axial vector couples to dark matter. If the dark matter relic density is set due to freeze-out via the axial vector, this strongly constrains the parameter space.

  1. Diabetes mellitus and the eye: axial length

    Huntjens, B.; O’Donnell, C.


    Background and aims: The refractive error of the eye is dependent on its axial length. Refractive error is known to fluctuate significantly in poorly controlled diabetic patients. Recently it has been reported that human eyes fluctuate in axial length during the day. However, this change is not detectable in all subjects, suggesting physiological influences such as diet. The purpose of this study was to investigate fluctuations in axial length and blood glucose levels (BGLs) in diabetic patie...

  2. Rigidity Constraints for Large Mesh Deformation

    Yong Zhao; Xin-Guo Liu; Qun-Sheng Peng; Hu-Jun Bao


    It is a challenging problem of surface-based deformation to avoid apparent volumetric distortions around largely deformed areas. In this paper, we propose a new rigidity constraint for gradient domain mesh deformation to address this problem. Intuitively the proposed constraint can be regarded as several small cubes defined by the mesh vertices through mean value coordinates. The user interactively specifies the cubes in the regions which are prone to volumetric distortions, and the rigidity constraints could make the mesh behave like a solid object during deformation. The experimental results demonstrate that our constraint is intuitive, easy to use and very effective.

  3. An On-Chip RBC Deformability Checker Significantly Improves Velocity-Deformation Correlation

    Chia-Hung Dylan Tsai


    Full Text Available An on-chip deformability checker is proposed to improve the velocity–deformation correlation for red blood cell (RBC evaluation. RBC deformability has been found related to human diseases, and can be evaluated based on RBC velocity through a microfluidic constriction as in conventional approaches. The correlation between transit velocity and amount of deformation provides statistical information of RBC deformability. However, such correlations are usually only moderate, or even weak, in practical evaluations due to limited range of RBC deformation. To solve this issue, we implemented three constrictions of different width in the proposed checker, so that three different deformation regions can be applied to RBCs. By considering cell responses from the three regions as a whole, we practically extend the range of cell deformation in the evaluation, and could resolve the issue about the limited range of RBC deformation. RBCs from five volunteer subjects were tested using the proposed checker. The results show that the correlation between cell deformation and transit velocity is significantly improved by the proposed deformability checker. The absolute values of the correlation coefficients are increased from an average of 0.54 to 0.92. The effects of cell size, shape and orientation to the evaluation are discussed according to the experimental results. The proposed checker is expected to be useful for RBC evaluation in medical practices.

  4. Rolling contact deformation of 1100 aluminum disks

    Hahn, G. T.; Huang, Q.


    The plastic deformation produced by pure, two dimensional, rolling contacts has been studied by subjecting 1100 aluminum disks to repeated contacts with well-defined relative peak contact pressures in the range 2 ≤ P 0/ k c ≤ 6.8. Two microstructural conditions are examined: as-received (warm worked) and annealed, displaying cyclic softening and cyclic hardening, respectively. Measurements of the distortion of wire markers imbedded in the rims, microhardness values of the plastically deformed layer, and changes in disk radius and width are reported. These are used to evaluate the plastic circumferential, radial, and axial displacements of the rim surface and the depth of the plastically deformed layer. These features are compared with the classical, elastic-quasi plastic analysis of rolling, and with recent elastic-plastic finite element calculations. The results show that the rim deformation state approaches plane strain when the disk width-to-Hertzian half contact width-ratio B/w ≥ 200. The presence of a solid lubricant has no detectable influence on the character of the plane strain deformation. The measurements of the per cycle forward (circumferential) displacements for the two conditions are self-consistent and agree with the finite element calculations when the resistance to plastic deformation is attributed to the instantaneous cyclic yield stress, but not when the resistance is identified with the initial monotonie yield stress. At the same time, the extent of the plastic zone is 5× greater than predicted by the analyses. These and other results can be rationalized by drawing on the special features of the resistance to cyclic deformation. They support the view that the deformation produced by the N th rolling contact is governed by the shape of the stress-strain hysteresis loop after the corresponding number of stress-strain cycles which depends on the cycle strain amplitude, degree of reversibility, and the strain path imposed by the contact

  5. System Study for Axial Vane Engine Technology

    Badley, Patrick R.; Smith, Michael R.; Gould, Cedric O.


    The purpose of this engine feasibility study was to determine the benefits that can be achieved by incorporating positive displacement axial vane compression and expansion stages into high bypass turbofan engines. These positive-displacement stages would replace some or all of the conventional compressor and turbine stages in the turbine engine, but not the fan. The study considered combustion occurring internal to an axial vane component (i.e., Diesel engine replacing the standard turbine engine combustor, burner, and turbine); and external continuous flow combustion with an axial vane compressor and an axial vane turbine replacing conventional compressor and turbine systems.

  6. Unsteady Flows in Axial Turbomachines

    Marble, F. E.; Rannie, W. D.


    Of the various unsteady flows that occur in axial turbomachines certain asymmetric disturbances, of wave length large in comparison with blade spacing, have become understood to a certain extent. These disturbances divide themselves into two categories: self-induced oscillations and force disturbances. A special type of propagating stall appears as a self-induced disturbance; an asymmetric velocity profile introduced at the compressor inlet constitutes a forced disturbance. Both phenomena have been treated from a unified theoretical point of view in which the asymmetric disturbances are linearized and the blade characteristics are assumed quasi-steady. Experimental results are in essential agreement with this theory wherever the limitations of the theory are satisfied. For the self-induced disturbances and the more interesting examples of the forced disturbances, the dominant blade characteristic is the dependence of total pressure loss, rather than the turning angle, upon the local blade inlet angle.

  7. The Emergence of Axial Parts

    Peter Svenonius


    Full Text Available Many languages have specialized locative words or morphemes translating roughly into words like ‘front,’ ‘back,’ ‘top,’ ‘bottom,’ ‘side,’ and so on. Often, these words are used instead of more specialized adpositions to express spatial meanings corresponding to ‘behind,’ ‘above,’ and so on. I argue, on the basis of a cross-linguistic survey of such expressions, that in many cases they motivate a syntactic category which is distinct from both N and P, which I call AxPart for ‘Axial Part’; I show how the category relates to the words which instantiate it, and how the meaning of the construction is derived from the combination of P[lace] elements, AxParts, and the lexical material which expresses them.

  8. Timing of Midcrustal Metamorphism, Melting, and Deformation in the Mount Everest Region of Southern Tibet Revealed by U(‐Th)‐Pb Geochronology

    John M. Cottle; Michael P. Searle; Matthew S. A. Horstwood; David J. Waters


    ...‐south transect in the Mount Everest region of southern Tibet provide new constraints on the timing and duration of thermal events associated with channel flow and the ductile extrusion of the Greater Himalayan Series (GHS...

  9. Numerical Investigation of the Performance of an Axial-Flow Pump with Tandem Blades

    YU Zhi-yi; LIU Shu-yan; WANG Guo-yu


    The performance characteristics of an axial-flow pump with tandem blades are studied based on the numerical computations. The arrangement of the pump impellers is established through the analysis of velocity triangles. With the commercial computational fluid dynamics (CFD) software NUMECA, the turbulent flow in the tandem axial-flow pump is simulated in various flow conditions. The detail flow structure in the leading edge region of the rear impeller is described, and the i nfluence of the deflection angle of the rear blade on the head performance is studied. According to the simulation, the performance comparison is made between the tandem axial-flow pump and the conventional two-stage axial-flow pump with a uniform impeller size. Results of the study indicate that the tandem axial-flow pump can work in a wider range with high efficiency.

  10. New region of deformation in the neutron-rich {sup 60}{sub 24}Cr{sub 36} and {sup 62}{sub 24}Cr{sub 38}

    Sorlin, O.; Donzaud, C.; Azaiez, F.; Bourgeois, C.; Chiste, V.; Guillemaud-Mueller, D.; Ibrahim, F.; Pougheon, F. [Institut de Physique Nucleaire, IN2P3-CNRS, F-91406 Orsay Cedex (France); Nowacki, F. [IReS, IN2P3-CNRS, Universite Louis Pasteur, BP 28, F-67037 Strasbourg Cedex (France); Angelique, J.C.; Grevy, S. [LPC, ISMRA, F-14050 Caen Cedex (France); Dlouhy, Z.; Mrasek, J. [Nuclear Physics Institute, AS CR, CZ 25068, Rez (Czech Republic); Kratz, K.L.; Pfeiffer, B. [Institut fuer Kernchemie, Universitaet Mainz, D-55128 Mainz (Germany); Lewitowicz, M.; de Oliveira Santos, F. [GANIL, B. P. 5027, F-14076 Caen Cedex (France); Lukyanov, S.M.; Penionzhkevich, Yu.E. [FLNR, JINR, 141980 Dubna, Moscow region (Russian Federation); Poves, A. [Departamento de Fisica Teorica, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Saint-Laurent, M.G.; Stanoiu, M.


    The neutron-rich nuclei {sub 23}{sup 60-63}V have been produced at GANIL via interactions of a 61.8A.MeV {sup 76}Ge beam with a {sup 58}Ni target. Beta-decay to {sub 24}{sup 60-63}Cr has been investigated using combined {beta}- and {gamma}-ray spectroscopy. Half-lives of the {sup 60-63}V nuclei have been determined, and the existence of a beta-decay isomer in the {sup 60}V nucleus is strongly supported. The observation of low-energy 2{sup +} states in {sup 60}Cr (646keV) and {sup 62}Cr (446keV) suggests that these isotopes are strongly deformed with {beta}{sub 2} {proportional_to}0.3. This is confirmed by shell model calculations which show the dominant influence of the intruder g and d orbitals to obtain low 2{sup +} energies in the neutron-rich Cr isotopes. (orig.)

  11. Pearlite transformation in high carbon steels deformed in metastable austenite region; Jun`antei austenite iki de kakoshita kotansoko no pearlite hentai

    Daito, Y.; Aihara, K.; Nishizawa, T. [Sumitomo Metal Industries, Ltd., Osaka (Japan)


    Pearlite structure was discussed noticing particularly on the state of nucleus composition, for the case when high carbon steels mainly structured by pearlite was processed in metastable austenite region below the point A1 which is thought a non-recrystallized region. When the processing amount is increased in the metastable austenite region, the size of pearlite colonies decreased. This is because of increase in nucleus producing site as a result of the processing. Even with a steel of eutectoid carbon concentration of an equilibrium diagram, proeuctoid ferrite is produced if the processing is given in the metastable austenite region. Furthermore, the production amount of the proeuctoid ferrite increased with increasing processing amount. If the processing is given in the metastable austenite region, the region that becomes a single pearlite structure shifted to hypereuctoid carbon concentration side as the transformation temperature has fallen. The result of an experiment performed in carbon concentration at which the single pearlite structure is obtained agreed well with drive force equilibrium line of ferrite and cementite as calculated based on the Gibbs energy. 18 refs., 11 figs., 1 tab.

  12. 3-D simulation of temporal change in tectonic deformation pattern and evolution of the plate boundary around the Kanto Region of Japan due to the collision of the Izu-Bonin Arc

    Hashima, A.; Sato, T.; Ito, T.; Miyauchi, T.; Furuya, H.; Tsumura, N.; Kameo, K.; Yamamoto, S.


    The Kanto region of Japan is in a highly complex tectonic setting with four plates interacting with each other: beneath Kanto, situated on the Eurasian and North American plates, the Philippine sea plate subducts and the Pacific plate further descends beneath the North American and Philippine sea plates, forming the unique trench-trench-trench triple junction on the earth. In addition, the Izu-Bonin (Ogasawara) arc on the Philippine sea plate is colliding with the Japan islands, which is considered to be a significant effect on the tectonics of Kanto. To reveal the present crustal structure and the present internal stress fields in such a complex tectonic setting, it is essential to comprehend them through the long-term tectonic evolution process. In this study, we estimate the temporal change in tectonic deformation pattern along with the geometry of the plate boundary around Kanto by numerical simulation with a kinematic plate subduction model based on the elastic dislocation theory. This model is based on the idea that mechanical interaction between plates can rationally be represented by the increase of the displacement discontinuity (dislocation) across plate interfaces. Given the 3-D geometry of plate interfaces, the distribution of slip rate vectors for simple plate subduction can be obtained directly from relative plate velocities. In collision zones, the plate with arc crust cannot easily descend because of its buoyancy. This can be represented by giving slip-rate deficit. When crustal deformation occurs, it also causes change in geometry of the plate boundary itself. This geometry change sensitively affects mechanical interaction at the plate boundary. Then the renewed plate-to-plete interaction alters crustal deformation rates. This feedback system has a large effect on collision zones. Indeed, the plate boundary around the Izu peninsula, the northernmost end of the Izu-Bonin arc, intends landward as large as 100 km. Iterating this effect sequentially

  13. Shock metamorphism of deformed quartz

    Gratz, Andrew J.; Christie, John; Tyburczy, James; Ahrens, Thomas; Pongratz, Peter


    The effect produced by shock loading (to peak pressures of 12 and 24) on deformed synthetic quartz containing a dislocation and abundant bubbles and small inclusions was investigated, and the relationships between preexisting dislocation density shock lamellae in the target material were examined. The resultant material was found to be inhomogeneously deformed and extremely fractured. Results of TEM examinations indicate that no change in dislocation density was caused by shock loading except in regions containing shock lamellae, where the dislocation density was lowered. The shock-induced defects tend to nucleate on and be controlled by preexisting stress concentrators; shock lamellae, glassy veins, and most curviplanar defects form in tension, presumably during release. An extremely mobile silica fluid is formed and injected into fractures during release, which forcibly removes crystalline fragments from vein walls. It is concluded that shock deformation in quartz is dominated by fracture and melting.

  14. Axial range of conjugate adaptive optics in two-photon microscopy

    Paudel, Hari P; Mertz, Jerome; Bifano, Thomas


    We describe an adaptive optics technique for two-photon microscopy in which the deformable mirror used for aberration compensation is positioned in a plane conjugate to the plane of the aberration. We demonstrate in a proof-of-principle experiment that this technique yields a large field of view advantage in comparison to standard pupil-conjugate adaptive optics. Further, we show that the extended field of view in conjugate AO is maintained over a relatively large axial translation of the deformable mirror with respect to the conjugate plane. We conclude with a discussion of limitations and prospects for the conjugate AO technique in two-photon biological microscopy.

  15. MgB2 cable made from two-axially rolled wires

    Kováč, P.; Hušek, I.; Melišek, T.


    Stabilized seven-core MgB2 cable has been made from two-axially rolled single-core wires with a Ti/Cu sheath. It was shown that drawing deformation applied prior to braiding influences the core density and consequently also the transport current density, Jc. A proper drawing deformation allows avoiding Jc degradation, and cable critical current density 104 A cm-2 at 9.5 T and 105 A cm-2 at 4.5 T can be reached at 4.2 K.

  16. Axial loading verification method for small bones using carrier fringes in speckle pattern interferometry

    Dávila, A.; Márquez, S.; Landgrave, E.; Vázquez, Z.; Vera, K.; Caudillo, C.


    A computerized system for real-time displacement visualization using carrier fringes in an electronic speckle in-plane sensitive interferometer allows force calibration for micro-displacement analysis of rat bones and verification of axial loading conditions. Once the force has been calibrated and the load is applied along the bone axis, the difference-of-phase method is used to obtain the phase map, which after phase unwrapping, allows the evaluation of the displacements produced by the bone deformation. The proposed method avoids common loading mistakes using first carrier fringes to assure that the loads are within the measuring capabilities of the in-plane interferometer and the Carré phase-stepping method to compensate for linear phase step miscalibration. The experimental results obtained with the calibration of loading forces and axial loading verification show the advantages of the system proposed here over a system which uses a cantilever configuration to make a similar bone deformation analysis.

  17. Application of two-axial rolling for multicore Bi(2223)/Ag tapes

    Kovác, P.; Husek, I.; Kopera, L.


    Multicore Ag-sheathed Bi(2223) tapes have been prepared by OPIT technique using the two-axial rolling deformation by active `Turk's head' roller. In comparison to wire drawing, the presented technique allows one to avoid the tensile stress during composite deformation and to increase the BSCCO-core density. A better homogeneity of filaments has been obtained by two-axial rolling. The transport critical current 0953-2048/10/12/025/img1 and its angular dependencies have been measured for single and 36 filament rectangular wires and tapes. Total tape widening influences the transport current density considerably but 0953-2048/10/12/025/img1 anisotropy at 0.1 T and 77 K is affected only slightly. Reduced 0953-2048/10/12/025/img1 anisotropy has been measured in a single core wire which has texturing of grains in two perpendicular rolling planes.

  18. Effect of petrophysical properties and deformation on vertical zoning of metasomatic rocks in U-bearing volcanic structures: A case of the Strel'tsovka caldera, Transbaikal region

    Petrov, V. A.; Andreeva, O. V.; Poluektov, V. V.


    The development of vertical zoning of wall-rock metasomatic alteration is considered with the Mesozoic Strel'tsovka caldera as an example. This caldera hosts Russia's largest uranium ore field. Metasomatic rocks with the participation of various phyllosilicates, carbonates, albite, and zeolites are widespread in the ore field. In the eastern block of the caldera, where the main uranium reserves are accommodated, hydromica metasomatic alteration gives way to beresitization with depth. Argillic alteration, which is typical of the western block, is replaced with hydromica and beresite alteration only at a significant depth. Postore argillic alteration is superposed on beresitized rocks in the lower part of the section. Two styles of vertical metasomatic zoning are caused by different modes of deformation in the western and eastern parts of the caldera. Variations of the most important petrophysical properties of host rocks—density, apparent porosity, velocities of P- and S-waves, dynamic Young's modulus, and Poisson coefficient—have been determined by sonic testing of samples taken from different depths. It is suggested that downward migration of the brittle-ductile transition zone could have been a factor controlling facies diversity of metasomatic rocks. Such a migration was caused by a new phase of tectonothermal impact accompanied by an increase in the strain rate or by emplacement of a new portion of heated fluid. Transient subsidence of the brittle-ductile boundary increases the depth of the hydrodynamically open zone related to the Earth's surface and accelerates percolation of cold meteoric water to a greater depth. As a result, the temperature of the hydrothermal solution falls down, increasing the vertical extent of argillic alteration. High-grade uranium mineralization is also localized more deeply than elsewhere.

  19. Experiments on the stability of a liquid bridge in an axial electric field

    Sankaran, Subramanian; Saville, D. A.


    The behavior of a neutrally buoyant liquid bridge was studied in the presence of axial electric fields. Silicone oil and a castor-oil-eugenol mixture were used to form cylinders with slenderness ratios larger than pi with strong, axial, dc electric fields. Below a certain field strength, a smooth transition to an axisymmetric, vaselike shape occurred. Circulation patterns were observed in these bridges. At lower field strengths, the bridge shape was more deformed and, at a well-defined field, pinch-off occurred. With ac fields, the field strength required to stabilize the bridge was higher and the collapse of the cylinder was much sharper. Upon interchanging the fluids, a steady axial field was found to destabilize cylinders with slenderness ratios less than 3. This behavior is consistent with that anticipated if the fluids behave as leaky dielectrics but not if they act as perfect dielectrics.

  20. Simultaneous Optical Measurements of Axial and Tangential Steady-State Blade Deflections

    Kurkov, Anatole P.; Dhadwal, Harbans S.


    Currently, the majority of fiber-optic blade instrumentation is being designed and manufactured by aircraft-engine companies for their own use. The most commonly employed probe for optical blade deflection measurements is the spot probe. One of its characteristics is that the incident spot on a blade is not fixed relative to the blade, but changes depending on the blade deformation associated with centrifugal and aerodynamic loading. While there are geometrically more complicated optical probe designs in use by different engine companies, this paper offers an alternate solution derived from a probe-mount design feature that allows one to change the probe axial position until the incident spot contacts either a leading or a trailing edge. By tracing the axial position of either blade edge one is essentially extending the deflection measurement to two dimensions, axial and tangential. The blade deflection measurements were obtained during a wind tunnel test of a fan prototype.

  1. Health and imaging outcomes in axial spondyloarthritis

    Machado, P.M.


    This thesis focuses on the assessment and monitoring of health and imaging outcomes in axial spondyloarthritis (SpA) and the relationship between these outcomes. Four major contributions to the understanding and management of axial SpA were made: 1) the improvement and facilitation of the assessment

  2. Interrelationships between Deformation and Metamorphic Events across the Western Hinterland Zone, NW Pakistan

    Asghar Ali; Mustafa Yar; Muhammad Asif Khan; Shah Faisal


    Microscopic to mesoscopic structural investigations and foliation intersection axes (FIAs) preserved in porphyroblasts reveal a very complex history of deformation and tectonism within the southwestern part of the western hinterland zone along the northern margin of the Indian plate, NW Pakistan. D1, D2, and D3 related structures in the southwestern part resemble the F1/F2, F3, and F4 re-lated structures in the northeastern part of the western hinterland zone. These structures developed at the same time through the same changes in the direction of bulk shortening in southwestern and northeastern parts of the western hinterland zone. FIA set 1 indicates NW-SE shortening. The D2 fab-rics, mineral lineations and fold axes indicate E-W shortening. FIA set 2, D3 fold axesand mineral lineations indicate NNE-SSW shortening. D3 deformation event is equivalent to the F4 deformation event in the northeastern part of the western hinterland zone. D4 fold axes, mineral stretching linea-tions and axial plane foliation suggest ENE-WSW shortening. The D4 NNW-SSE fabrics, which formed in the region after the formation of the MMT (main mantle thrust), Khairabad-Panjal thrust fault, Hissartang thrust fault and MBT (main boundary thrust), likely resulted from ENE-WSW bulk shortening related to development of the Hazara-Kashmir syntaxis.

  3. Vertebral column deformities in white-beaked dolphins from the eastern North Atlantic.

    Bertulli, Chiara G; Galatius, Anders; Kinze, Carl C; Rasmussen, Marianne H; Deaville, Rob; Jepson, Paul; Vedder, Elisabeth J; Sánchez Contreras, Guillermo J; Sabin, Richard C; Watson, Alastair


    Five white-beaked dolphins Lagenorhynchus albirostris with outwardly vertebral kyphosis, kyphoscoliosis or lordosis were identified during a photo-identification survey of over 400 individuals (2002-2013) in Faxaflói and Skjálfandi Bays, Iceland. In addition, 3 stranding reports from Denmark, The Netherlands and the UK were analysed, providing both external observation and post mortem details of axial deviations of the vertebral column in this species. Two of the free-ranging cases and 2 of the stranded specimens appeared to have an acquired disease, either as a direct result of trauma, or indirectly from trauma/wound and subsequent infection and bony proliferation, although we were unable to specifically identify the causes. Our data represent a starting point to understand vertebral column deformations and their implications in white-beaked dolphins from the eastern North Atlantic. We recommend for future necropsy cases to conduct macro- and microscopic evaluation of muscle from both sides of the deformed region, in order to assess chronic or acute conditions related to the vertebral deformations and cause of death.

  4. Universal Axial Fluctuations in Optical Tweezers

    Ribezzi-Crivellari, Marco; Ritort, Felix


    Optical tweezers allow the measurement of fluctuations at the nano-scale, in particular fluctuations in the end-to-end distance in single molecules. Fluctuation spectra can yield valuable information, but they can easily be contaminated by instrumental effects. We identify axial fluctuations, i.e. fluctuations of the trapped beads in the direction of light propagation, as one of these instrumental effects. Remarkably, axial fluctuations occur on a characteristic timescale similar to that of conformational (folding) transitions, which may lead to misinterpretation of the experimental results. We show that a precise measurement of the effect of force on both axial and conformational fluctuations is crucial to disentangle them. Our results on axial fluctuations are captured by a simple and general formula valid for all optical tweezers setups and provide experimentalists with a general strategy to distinguish axial fluctuations from conformational transitions.

  5. Novel Integration Radial and Axial Magnetic Bearing

    Blumenstock, Kenneth; Brown, Gary


    Typically, fully active magnetically suspended systems require one axial and two radial magnetic bearings. Combining radial and axial functions into a single device allows for more compact and elegant packaging. Furthermore, in the case of high-speed devices such as energy storage flywheels, it is beneficial to minimize shaft length to keep rotor mode frequencies as high as possible. Attempts have been made to combine radial and axial functionality, but with certain drawbacks. One approach requires magnetic control flux to flow through a bias magnet reducing control effectiveness, thus resulting in increased resistive losses. This approach also requires axial force producing magnetic flux to flow in a direction into the rotor laminate that is undesirable for minimizing eddy-current losses resulting in rotational losses. Another approach applies a conical rotor shape to what otherwise would be a radial heteropolar magnetic bearing configuration. However, positional non-linear effects are introduced with this scheme and the same windings are used for bias, radial, and axial control adding complexity to the controller and electronics. For this approach, the amount of axial capability must be limited. It would be desirable for an integrated radial and axial magnetic bearing to have the following characteristics; separate inputs for radial and axial control for electronics and control simplicity, all magnetic control fluxes should only flow through their respective air gaps and should not flow through any bias magnets for minimal resistive losses, be of a homopolar design to minimize rotational losses, position related non-linear effects should be minimized, and dependent upon the design parameters, be able to achieve any radial/axial force or power ratio as desired. The integrated radial and axial magnetic bearing described in this paper exhibits all these characteristics. Magnetic circuit design, design equations, and magnetic field modeling results will be presented.

  6. Novel Integrated Radial and Axial Magnetic Bearing

    Blumenstock, Kenneth A.; Brown, Gary L.; Powers, Edward I. (Technical Monitor)


    Typically, fully active magnetically suspended systems require one axial and two radial magnetic bearings. Combining radial and axial functions into a single device allows for more compact and elegant packaging. Furthermore, in the case of high-speed devices such as energy storage flywheels, it is beneficial to minimize shaft length to keep rotor mode frequencies as high as possible. Attempts have been made to combine radial and axial functionality, but with certain drawbacks. One approach requires magnetic control flux to flow through a bias magnet reducing control effectiveness, thus resulting in increased resistive losses. This approach also requires axial force producing magnetic flux to flow in a direction into the rotor laminate that is undesirable for minimizing eddy-current losses resulting in rotational losses. Another approach applies a conical rotor shape to what otherwise would be a radial heteropolar magnetic bearing configuration. However, positional non-linear effects are introduced with this scheme and the same windings are used for bias, radial, and axial control adding complexity to the controller and electronics. For this approach, the amount of axial capability must be limited. It would be desirable for an integrated radial and axial magnetic bearing to have the following characteristics, separate inputs for radial and axial control for electronics and control simplicity, all magnetic control fluxes should only flow through their respective air gaps and should not flow through any bias magnets for minimal resistive losses, be of a homopolar design to minimize rotational losses, position related non-linear effects should be minimized, and dependent upon the design parameters, be able to achieve any radial/axial force or power ratio as desired. The integrated radial and axial magnetic bearing described in this paper exhibits all these characteristics. Magnetic circuit design, design equations, and analysis results will be presented.

  7. Analysis of Mining Terrain Deformation Characteristics with Deformation Information System

    Blachowski, Jan; Milczarek, Wojciech; Grzempowski, Piotr


    the case study of a coal mining region in SW Poland where it has been applied to study characteristics and map mining induced ground deformations in a city in the last two decades of underground coal extraction and in the first decade after the end of mining. The mining subsidence area and its deformation parameters (tilt and curvature) have been calculated and the latter classified and mapped according to the Polish regulations. In addition possible areas of ground deformation have been indicated based on multivariate spatial data analysis of geological and mining operation characteristics with the geographically weighted regression method.

  8. 龙门山北段阳平关地区构造变形序列特征%Longmen Mountains region north deformation sequence features over Yangpingguan zone

    任清军; 刘顺


    Yangpingguan area is located between the Longmen Mountain orogenic belt and Micang Mountain orogenic belt, which are well known as mainland of orogenic belts. The tectonic deformation of Yangpingguan faults is effected obviously by above two orogenic belts during the faults formation. Based on research on the plates and fault plane of Yangpingguan fault, tectonic deformation times and regional tectonic stress field were discussed. It is concluded that there are six tectonic stress field, such as the first period with EN - SW squeeze, the second period with NW - SE squeeze, the third period with S - N squeeze, the fourth period with EN - SW squeeze , the fifth issue period with NW - SE squeeze and the sixth period with EN - SW stretch. Tectonic deformation of Yangpingguan region continued progressed from late In-dosinian to Himalayan periods.%龙门山造山带和米仓山造山带是中国大陆颇有影响力的造山带.阳平关地区位于前两者之间,阳平关断层的形成以及后期的构造变形均受这二者的明显控制和影响.通过对阳平关断层上盘、断层面以及下盘的实测研究,对阳平关地区的构造变形期次与区域构造应力场作了探讨.认为主要区域构造应力场有六期,第一期为NE - SW向挤压,第二期为NW- SE向挤压,第三期为S-N向挤压,第四期为NE - SW向挤压,第五期为NW - SE向挤压,第六期NE - SW向拉伸.阳平关地区构造变形从印支晚期一直持续到喜马拉雅期.

  9. Association between axial length and horizontal and vertical globe diameters.

    Jonas, Jost B; Ohno-Matsui, Kyoko; Holbach, Leonard; Panda-Jonas, Songhomitra


    To assess relationships between axial length and the horizontal and vertical globe diameters. The study consisted of enucleated human eyes. The horizontal, vertical, and sagittal diameters were measured. The study included 135 globes removed because of malignant uveal melanoma (111 globes) or end-stage painful glaucoma (n = 24 eyes). Mean axial, horizontal, and vertical diameters were 24.6 ± 2.6 mm (range: 20-35 mm), 23.7 ± 1.4 mm (range: 21-29 mm) and 23.7 ± 1.4 mm (range: 20-29 mm) respectively. The horizontal diameter and vertical diameter did not differ significantly (P = 0.92), while both were significantly (P globe diameter (P globe diameter = 0.84 × horizontal globe diameter + 3.69). The axial diameter was significantly (P 24 mm, the horizontal and vertical globe diameter increased by a lower amount of 0.19 and 0.21 mm, respectively, for each mm increase in axial diameter. Myopic enlargement of the globe beyond an axial length of 24 mm takes place predominantly in the sagittal axis, leading to a change in the globe form from a sphere to an elongated form. It fits with the notion that myopic elongation may occur by an elongation of the eye walls in regions close to the globe's equator.

  10. Deformations of crystal frameworks

    Borcea, Ciprian S


    We apply our deformation theory of periodic bar-and-joint frameworks to tetrahedral crystal structures. The deformation space is investigated in detail for frameworks modelled on quartz, cristobalite and tridymite.

  11. Deformed General Relativity

    Bojowald, Martin


    Deformed special relativity is embedded in deformed general relativity using the methods of canonical relativity and loop quantum gravity. Phase-space dependent deformations of symmetry algebras then appear, which in some regimes can be rewritten as non-linear Poincare algebras with momentum-dependent deformations of commutators between boosts and time translations. In contrast to deformed special relativity, the deformations are derived for generators with an unambiguous physical role, following from the relationship between canonical constraints of gravity with stress-energy components. The original deformation does not appear in momentum space and does not give rise to non-locality issues or problems with macroscopic objects. Contact with deformed special relativity may help to test loop quantum gravity or restrict its quantization ambiguities.

  12. Numerical Algorithms for Boundary Problems with Disturbed Axial Symmetry

    Ivanov, V


    The axial symmetry in the real devices of image electron optics is always disturbed by small defects in manufacturing and assembly. The authors present a complete method for the numerical simulation of problems with such defects, which includes the algorithms for singularity extraction in a numerical solution of the boundary problem described by the Helmholtz equation. The effective recurrent formulas for evaluation of the kernels of integral representations and their derivatives are constructed. New modification of the well-known Bruns-Bertein method is given, and correlation of this method with an integral equation in variations is investigated. The algorithms are implemented in the codes POISSON-2 and OPTICS-2. The results of the numerical simulation for various test problems with different kinds of boundary deformation are given.

  13. Identification of an amphipathic helix important for the formation of ectopic septin spirals and axial budding in yeast axial landmark protein Bud3p.

    Guo, Jia; Gong, Ting; Gao, Xiang-Dong


    Correct positioning of polarity axis in response to internal or external cues is central to cellular morphogenesis and cell fate determination. In the budding yeast Saccharomyces cerevisiae, Bud3p plays a key role in the axial bud-site selection (axial budding) process in which cells assemble the new bud next to the preceding cell division site. Bud3p is thought to act as a component of a spatial landmark. However, it is not clear how Bud3p interacts with other components of the landmark, such as the septins, to control axial budding. Here, we report that overexpression of Bud3p causes the formation of small septin rings (∼1 µm in diameter) and arcs aside from previously reported spiral-like septin structures. Bud3p closely associates with the septins in vivo as Bud3p colocalizes with these aberrant septin structures and forms a complex with two septins, Cdc10p and Cdc11p. The interaction of Bud3p with the septins may involve multiple regions of Bud3p including 1-858, 850-1220, and 1221-1636 a.a. since they all target to the bud neck but exhibit different effects on septin organization when overexpressed. In addition, our study reveals that the axial budding function of Bud3p is mediated by the N-terminal region 1-858. This region shares an amphipathic helix (850-858) crucial for bud neck targeting with the middle portion 850-1103 involved in the formation of ectopic septin spirals and rings. Interestingly, the Dbl-homology domain located in 1-858 is dispensable for axial bud-site selection. Our findings suggest that multiple regions of Bud3p ensure efficient targeting of Bud3p to the bud neck in the assembly of the axial landmark and distinct domains of Bud3p are involved in axial bud-site selection and other cellular processes.

  14. Axial-torsional fatigue: A study of tubular specimen thickness effects

    Bonacuse, Peter J.; Kalluri, Sreeramesh


    A room-temperature experimental program was conducted on AISI type 316 stainless steel to determine the effect of wall thickness on the cyclic deformation behavior and fatigue life of thin-wall, tubular, axial-torsional fatigue specimens. The following experimental variables were examined in this study: the depth of the surface work-hardened layer produced in specimen machining, and the effects of strain range and axial-torsional strain phasing. Tubular fatigue specimens were fabricated with wall thicknesses of 1.5, 2.0, and 2.5 mm. One as-fabricated specimen from each wall thickness was sectioned for microstructural examination and microhardness measurement. A specimen of each wall thickness was tested at each of three conditions - high strain range in-phase, low strain range in-phase, and low strain range out-of-phase - for a total of nine axial-torsional fatigue experiments. The machining-induced work-hardened zone, as a percentage of the gage section material, was found to have a minimal effect on both deformation behavior and fatigue life. Also, little or no variation in fatigue life or deformation behavior as a function of wall thickness was observed. Out-of-phase fatigue tests displayed shorter fatigue lives and more cyclic hardening than in-phase tests.

  15. Study on Constitutive Model for Root System of Korshinsk peashrub in Axial Tension

    Guo-jian Feng


    Full Text Available Constitutive model for root system of Korshinsk peashrub (Caragana korshinskii Kom. in axial tension is an important tool for analyzing the mechanism of soil reinforcement of root system. This model enables a mechanical analysis on strength and deformation of root system and root-soil complex. We carried out axial tension test of root system of Korshinsk peashrub in this paper and discussed the stress-strain relation. Based on the experimental results, the constitutive model for root system of Korshinsk peashrub in axial tension was established. Results showed that: (1 When the strain was smaller than 4%, the stress-strain relation was linear for single root, corresponding to linear elastic deformation; when the strain was larger than 4%, the single root underwent plastic deformation; (2 Elastic modulus of the root system was related to root diameter by a power function. The smaller the root diameter, the higher the elastic modulus was; (3 Root diameter was related to the ultimate tensile strength of root also by a power function. The smaller the root diameter, the higher the ultimate tensile strength of root was; (4 The tensile stress-strain curve of the root system divided into ascending segment and descending segment, which was fitted by parabola and curvilinear model, respectively.

  16. Non-permanent GPS data for regional-scale kinematics: reliable deformation rate before the 6 April, 2009, earthquake in the L'Aquila area

    Fabiana Loddo


    Full Text Available A GPS-based geodetic study at a regional scale requires the availability of a dense network that is characterized by 10 km to 30 km spacing, typically followed in a few continuous GPS stations (CGPSs and several non-permanent GPS stations (NPSs. As short observation times do not allow adequate noise modeling, NPS data need specific processing where the main differences between NPSs and CGPSs are taken into account: primarily time-series length and antenna repositioning error. The GPS data collected in the 1999-2007 time-span from non-permanent measurement campaigns in the central Apennine area (Italy that was recently hit by the Mw 6.3 L'Aquila earthquake (April 6, 2009 are here further analyzed to compute a reliable strain-rate field at a regional scale. Moreover, areas characterized by different kinematics are recognized, and a complete characterization of the regional-scale kinematics is attempted. These new data can be interpreted as indicators from the viewpoint of seismic risk assessment.



    The efficiency of small axial fan used as cooling device in information technology machines is extremely low, comparing with conventional axial fan which is much larger than small fan. In the design of conventional axial fan, the axial velocity of the inlet flow is regarded as uniform along the blade span. However, in case of the small fan, the velocity could not be uniform.Because the hub-tip ratiois so large that the blade span will be too short to keep the uniform flow region. So, it is im...

  18. Axial force measurement for esophageal function testing

    Flemming H Gravesen; Peter Funch-Jensen; Hans Gregersen; Asbjφrn Mohr Drewes


    The esophagus serves to transport food and fluid from the pharynx to the stomach. Manometry has been the "golden standard" for the diagnosis of esophageal motility diseases for many decades. Hence, esophageal function is normally evaluated by means of manometry even though it reflects the squeeze force (force in radial direction) whereas the bolus moves along the length of esophagus in a distal direction. Force measurements in the longitudinal (axial) direction provide a more direct measure of esophageal transport function. The technique used to record axial force has developed from external force transducers over in-vivo strain gauges of various sizes to electrical impedance based measurements. The amplitude and duration of the axial force has been shown to be as reliable as manometry. Normal, as well as abnormal, manometric recordings occur with normal bolus transit, which have been documented using imaging modalities such as radiography and scintigraphy. This inconsistency using manometry has also been documented by axial force recordings. This underlines the lack of information when diagnostics are based on manometry alone. Increasing the volume of a bag mounted on a probe with combined axial force and manometry recordings showed that axial force amplitude increased by 130% in contrast to an increase of 30% using manometry. Using axial force in combination with manometry provides a more complete picture of esophageal motility, and the current paper outlines the advantages of using this method.

  19. Axial force measurement for esophageal function testing.

    Gravesen, Flemming H; Funch-Jensen, Peter; Gregersen, Hans; Drewes, Asbjørn Mohr


    The esophagus serves to transport food and fluid from the pharynx to the stomach. Manometry has been the "golden standard" for the diagnosis of esophageal motility diseases for many decades. Hence, esophageal function is normally evaluated by means of manometry even though it reflects the squeeze force (force in radial direction) whereas the bolus moves along the length of esophagus in a distal direction. Force measurements in the longitudinal (axial) direction provide a more direct measure of esophageal transport function. The technique used to record axial force has developed from external force transducers over in-vivo strain gauges of various sizes to electrical impedance based measurements. The amplitude and duration of the axial force has been shown to be as reliable as manometry. Normal, as well as abnormal, manometric recordings occur with normal bolus transit, which have been documented using imaging modalities such as radiography and scintigraphy. This inconsistency using manometry has also been documented by axial force recordings. This underlines the lack of information when diagnostics are based on manometry alone. Increasing the volume of a bag mounted on a probe with combined axial force and manometry recordings showed that axial force amplitude increased by 130% in contrast to an increase of 30% using manometry. Using axial force in combination with manometry provides a more complete picture of esophageal motility, and the current paper outlines the advantages of using this method.

  20. The crustal micro-deformation anomaly and the credible precursor*

    张雁滨; 蒋骏; 钱家栋; 陈京; 和升棋; 张燕; 和平


    @@ What is a credible seismic precursor in observation of deformation A real seismic precursor ought to be resulted from the variations in the earth strain and stress. The deformation observation can provide the information during earthquake gestation and occurrence period for us. Usually the seismic precursors can be divided into field and epicentral region precursors. The precursor information is very useful for seismic prediction from epicentral region or near epicentral region. Micro-deformation observation mainly includes tilt, strain and gravity observation. Compared with GPS, geodesy and mobile deformation observation, micro-deformation (tilt, strain) shows the change of deformation which is continual in a limited volume with dominant observed range of 10(6~10(10 m. Because the variation of the crustal nature and cracking can be directly obtained by micro-deformation observation, it is an effective way to find middle-short term and short-term precursor.

  1. Three-dimensional bending, torsion and axial compression of the femoropopliteal artery during limb flexion.

    MacTaggart, Jason N; Phillips, Nicholas Y; Lomneth, Carol S; Pipinos, Iraklis I; Bowen, Robert; Baxter, B Timothy; Johanning, Jason; Longo, G Matthew; Desyatova, Anastasia S; Moulton, Michael J; Dzenis, Yuris A; Kamenskiy, Alexey V


    High failure rates of femoropopliteal artery reconstruction are commonly attributed to complex 3D arterial deformations that occur with limb movement. The purpose of this study was to develop a method for accurate assessment of these deformations. Custom-made stainless-steel markers were deployed into 5 in situ cadaveric femoropopliteal arteries using fluoroscopy. Thin-section CT images were acquired with each limb in the straight and acutely bent states. Image segmentation and 3D reconstruction allowed comparison of the relative locations of each intra-arterial marker position for determination of the artery's bending, torsion and axial compression. After imaging, each artery was excised for histological analysis using Verhoeff-Van Gieson staining. Femoropopliteal arteries deformed non-uniformly with highly localized deformations in the proximal superficial femoral artery, and between the adductor hiatus and distal popliteal artery. The largest bending (11±3-6±1 mm radius of curvature), twisting (28±9-77±27°/cm) and axial compression (19±10-30±8%) were registered at the adductor hiatus and the below knee popliteal artery. These deformations were 3.7, 19 and 2.5 fold more severe than values currently reported in the literature. Histology demonstrated a distinct sub-adventitial layer of longitudinally oriented elastin fibers with intimal thickening in the segments with the largest deformations. This endovascular intra-arterial marker technique can quantify the non-uniform 3D deformations of the femoropopliteal artery during knee flexion without disturbing surrounding structures. We demonstrate that 3D arterial bending, torsion and compression in the flexed lower limb are highly localized and are substantially more severe than previously reported.


    YANG Xiao-dong; CHEN Li-qun


    Parametric vibration of an axially moving, elastic, tensioned beam with pulsating speed was investigated in the vicinity of subharmonic and combination resonance. The method of averaging was used to yield a set of autonomous equations when the parametric excitation frequency is twice or the combination of the natural frequencies. Instability boundaries were presented in the plane of parametric frequency and amplitude. The analytical results were numerically verified. The effects of the viscoelastic damping, steady speed and tension on the instability boundaries were numerically demonstrated. It is found that the viscoelastic damping decreases the instability regions and the steady speed and the tension make the instability region drift along the frequency axis.

  3. Axially Symmetric Shear-free Fluids in $f(R,T)$ Gravity

    Noureen, Ifra


    In this work we have discussed the implications of shear-free condition on axially symmetric anisotropic gravitating objects in $f(R,T)$ theory. Restricted axial symmetry ignoring rotation and reflection enteries is taken into account for establishment of instability range. Implementation of linear perturbation on constitutive modified dynamical equations yield evolution equation. This equation associates adiabatic index $\\Gamma$ with material and dark source components defining stable and unstable regions in Newtonian (N) and post-Newtonian (pN) approximations.

  4. New Anomaly of the Axial-Vector Current

    HE Han-Xin


    By computing the axial-vector current operator equation, we find the anomalous axial-vector curl equation besides the well-known anomalous axial-vector divergence equation (the Adler-Bell-Jackiw anomaly) and discuss its implication.``

  5. Growth-induced axial buckling of a slender elastic filament embedded in an isotropic elastic matrix

    O'Keeffe, Stephen G.


    We investigate the problem of an axially loaded, isotropic, slender cylinder embedded in a soft, isotropic, outer elastic matrix. The cylinder undergoes uniform axial growth, whilst both the cylinder and the surrounding elastic matrix are confined between two rigid plates, so that this growth results in axial compression of the cylinder. We use two different modelling approaches to estimate the critical axial growth (that is, the amount of axial growth the cylinder is able to sustain before it buckles) and buckling wavelength of the cylinder. The first approach treats the filament and surrounding matrix as a single 3-dimensional elastic body undergoing large deformations, whilst the second approach treats the filament as a planar, elastic rod embedded in an infinite elastic foundation. By comparing the results of these two approaches, we obtain an estimate of the foundation modulus parameter, which characterises the strength of the foundation, in terms of the geometric and material properties of the system. © 2013 Elsevier Ltd. All rights reserved.

  6. Deformable Nanolaminate Optics

    Olivier, S S; Papavasiliou, A P; Barbee, T W; Miles, R R; Walton, C C; Cohn, M B; Chang, K


    We are developing a new class of deformable optic based on electrostatic actuation of nanolaminate foils. These foils are engineered at the atomic level to provide optimal opto-mechanical properties, including surface quality, strength and stiffness, for a wide range of deformable optics. We are combining these foils, developed at Lawrence Livermore National Laboratory (LLNL), with commercial metal processing techniques to produce prototype deformable optics with aperture sizes up to 10 cm and actuator spacing from 1 mm to 1 cm and with a range of surface deformation designed to be as much as 10 microns. The existing capability for producing nanolaminate foils at LLNL, coupled with the commercial metal processing techniques being used, enable the potential production of these deformable optics with aperture sizes of over 1 m, and much larger deformable optics could potentially be produced by tiling multiple deformable segments. In addition, based on the fabrication processes being used, deformable nanolaminate optics could potentially be produced with areal densities of less than 1 kg per square m for applications in which lightweight deformable optics are desirable, and deformable nanolaminate optics could potentially be fabricated with intrinsically curved surfaces, including aspheric shapes. We will describe the basic principles of these devices, and we will present details of the design, fabrication and characterization of the prototype deformable nanolaminate optics that have been developed to date. We will also discuss the possibilities for future work on scaling these devices to larger sizes and developing both devices with lower areal densities and devices with curved surfaces.

  7. Focal mechanisms in the southern Aegean from temporary seismic networks – implications for the regional stress field and ongoing deformation processes

    W. Friederich


    Full Text Available The lateral variation of the stress field in the southern Aegean plate and the subducting Hellenic slab is determined from recordings of seismicity obtained with the CYCNET and EGELADOS networks in the years from 2002 to 2007. First motions from 7000 well-located microearthquakes were analysed to produce 540 well-constrained focal mechanisms. They were complemented by another 140 derived by waveform matching of records from larger events. Most of these earthquakes fall into 16 distinct spatial clusters distributed over the southern Aegean region. For each cluster, a stress inversion could be carried out yielding consistent estimates of the stress field and its spatial variation. At crustal levels, the stress field is generally dominated by a steeply dipping compressional principal stress direction except in places where coupling of the subducting slab and overlying plate come into play. Tensional principal stresses are generally subhorizontal. Just behind the forearc, the crust is under arc-parallel tension whereas in the volcanic areas around Kos, Columbo and Astypalea tensional and intermediate stresses are nearly degenerate. Further west and north, in the Santorini–Amorgos graben and in the area of the islands of Mykonos, Andros and Tinos, tensional stresses are significant and point around the NW–SE direction. Very similar stress fields are observed in western Turkey with the tensional axis rotated to NNE–SSW. Intermediate-depth earthquakes below 100 km in the Nisyros region indicate that the Hellenic slab experiences slab-parallel tension at these depths. The direction of tension is close to east–west and thus deviates from the local NW-oriented slab dip presumably owing to the segmentation of the slab. Beneath the Cretan sea, at shallower levels, the slab is under NW–SE compression. Tensional principal stresses in the crust exhibit very good alignment with extensional strain rate principal axes derived from GPS velocities except

  8. SU-E-J-100: The Combination of Deformable Image Registration and Regions-Of-Interest Mapping Technique to Accomplish Accurate Dose Calculation On Cone Beam Computed Tomography for Esophageal Cancer

    Huang, B-T; Lu, J-Y [Cancer Hospital of Shantou University Medical College, Shantou (China)


    Purpose: We introduce a new method combined with the deformable image registration (DIR) and regions-of-interest mapping (ROIM) technique to accurately calculate dose on daily CBCT for esophageal cancer. Methods: Patients suffered from esophageal cancer were enrolled in the study. Prescription was set to 66 Gy/30 F and 54 Gy/30 F to the primary tumor (PTV66) and subclinical disease (PTV54) . Planning CT (pCT) were segmented into 8 substructures in terms of their differences in physical density, such as gross target volume (GTV), venae cava superior (SVC), aorta, heart, spinal cord, lung, muscle and bones. The pCT and its substructures were transferred to the MIM software to readout their mean HU values. Afterwards, a deformable planning CT to daily KV-CBCT image registration method was then utilized to acquire a new structure set on CBCT. The newly generated structures on CBCT were then transferred back to the treatment planning system (TPS) and its HU information were overridden manually with mean HU values obtained from pCT. Finally, the treatment plan was projected onto the CBCT images with the same beam arrangements and monitor units (MUs) to accomplish dose calculation. Planning target volume (PTV) and organs at risk (OARs) from both of the pCT and CBCT were compared to evaluate the dose calculation accuracy. Results: It was found that the dose distribution in the CBCT showed little differences compared to the pCT, regardless of whether PTV or OARs were concerned. Specifically, dose variation in GTV, PTV54, PTV66, SVC, lung and heart were within 0.1%. The maximum dose variation was presented in the spinal cord, which was up to 2.7% dose difference. Conclusion: The proposed method combined with DIR and ROIM technique to accurately calculate dose distribution on CBCT for esophageal cancer is feasible.

  9. Particle classification in Taylor vortex flow with an axial flow

    Ohmura, N.; Suemasu, T.; Asamura, Y.


    Particle classification phenomenon in Taylor vortex flow with an axial flow was investigated experimentally and numerically. The flow-visualization experiment by a laser-induced fluorescence method clearly revealed that there existed two distinct mixing regions at low Reynolds numbers. The tracer near the vortex cell boundary was rapidly transported axially owing to the bypass flow effect. On the other hand, the fluid element was confined to the vortex core region without being exchanged with the outer flow region. In order to observe particle classification phenomenon, polymethyl methacrylate (PMMA) particles suspended in the same aqueous solution of glycerol as the working fluid were fed into the top of the apparatus. Particle size was initially ranging from 10 to 80 µm. The ratio of the particle density to the fluid density was 1.04-1.05, which means the density difference between particle and fluid is very small. The suspended solution was withdrawn using a hypodermic needle every a certain time period at 30 mm above the bottom of apparatus. The fluid was sampled both near the outer wall and in vortex core. The particles sampled at 42 min having the size of 20-50 µm were mainly observed in the vortex core region. On the other hand, a large population of particles having the size of about 50-80 µm could be seen in the outer region of vortex. It was found that large particles located near the outer edge of vortices were quickly transported axially owing to the bypass flow effect. Numerical simulation also revealed that the loci of particles depended on the particle size.

  10. Permanent Deformation of Highway Subgrade Soils


    Based on a comprehensive review of the literature and preliminary testing performed on a subgrade soil, a testing methodology for repeated load testing was established. This testing protocol was verified using data from subgrade soil. The successful application of this testing protocol on the two subgrade soils proves that it can provide consistent, reliable results. A power model was used to fit the accumulated axial strain over load repetitions with the first hundred cycles excluded from the data set. A number of factors influencing the accumulation of permanent deformation were investigated. The results indicate that confining pressure, load frequency and density are relatively minor contributors to deformation accumulation. Moisture content, deviator stress and first cycle freeze-thaw are major factors governing permanent deformation. The effects of stress history resulting from staged loading are dependent upon the level of applied deviator stress. The interpretation of the rich and consistent deformation data derived from this testing protocol provide valuable insights for transportation engineers relative to the design, construction, operation and maintenance strategy of highway subgrades as well as railway roadbeds.

  11. In-situ studies of bulk deformation structures: Static properties under load and dynamics during deformation

    Jakobsen, Bo


    The main goal of the study presented in this thesis was to perform in-situ investigations on deformation structures in plastically deformed polycrystalline copper at low degrees of tensile deformation (metals. Anovel synchrotron...... grains in polycrystalline samples during tensile deformation. We have shown that the resulting 3D reciprocal space maps from tensile deformed copper comprise a pronounced structure, consisting of bright sharp peaks superimposed on a cloud of enhanced intensity. Based on the integrated intensity......, the width of the peaks, and spatial scanning experiments it is concluded that the individual peaks arise from individual dislocation-free regions (the subgrains) in the dislocation structure. The cloud is attributed to the dislocation rich walls. Samples deformed to 2% tensile strain were investigated under...

  12. Historical overview of spinal deformities in ancient Greece

    Kaspiris Angelos


    Full Text Available Abstract Little is known about the history of spinal deformities in ancient Greece. The present study summarizes what we know today for diagnosis and management of spinal deformities in ancient Greece, mainly from the medical treatises of Hippocrates and Galen. Hippocrates, through accurate observation and logical reasoning was led to accurate conclusions firstly for the structure of the spine and secondly for its diseases. He introduced the terms kyphosis and scoliosis and wrote in depth about diagnosis and treatment of kyphosis and less about scoliosis. The innovation of the board, the application of axial traction and even the principle of trans-abdominal correction for correction of spinal deformities have their origin in Hippocrates. Galen, who lived nearly five centuries later impressively described scoliosis, lordosis and kyphosis, provided aetiologic implications and used the same principles with Hippocrates for their management, while his studies influenced medical practice on spinal deformities for more than 1500 years.

  13. Historical overview of spinal deformities in ancient Greece

    Vasiliadis, Elias S; Grivas, Theodoros B; Kaspiris, Angelos


    Little is known about the history of spinal deformities in ancient Greece. The present study summarizes what we know today for diagnosis and management of spinal deformities in ancient Greece, mainly from the medical treatises of Hippocrates and Galen. Hippocrates, through accurate observation and logical reasoning was led to accurate conclusions firstly for the structure of the spine and secondly for its diseases. He introduced the terms kyphosis and scoliosis and wrote in depth about diagnosis and treatment of kyphosis and less about scoliosis. The innovation of the board, the application of axial traction and even the principle of trans-abdominal correction for correction of spinal deformities have their origin in Hippocrates. Galen, who lived nearly five centuries later impressively described scoliosis, lordosis and kyphosis, provided aetiologic implications and used the same principles with Hippocrates for their management, while his studies influenced medical practice on spinal deformities for more than 1500 years. PMID:19243609

  14. Self-deformation in a dc driven helium jet micro discharge

    Xu, Shaofeng


    We report on the experimental observation of three dimensional self-deformation in an atmospheric micro discharge of the helium microjet through a tube into the ambient air upon a water electrode. The geometry of the discharge system is axial symmetric. While decreasing the discharge current, three dimensional collective motion of plasma filaments are directly observed. The three dimensional configuration of the discharge self changed from an axial symmetrical horn to a rectangular horn when the water acts as a cathode.

  15. Self-deformation in a direct current driven helium jet micro discharge

    Xu, S. F.; Zhong, X. X., E-mail: [State Key Laboratory of Advanced Optical Communication Systems and Networks and Key Laboratory for Laser Plasmas (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240 (China)


    We report on the experimental observation of three dimensional self-deformation in an atmospheric micro discharge of the helium microjet through a tube into the ambient air upon a water electrode. The geometry of the discharge system is axial symmetric. While decreasing the discharge current, three dimensional collective motion of plasma filaments is directly observed. The three dimensional configuration of the discharge self changed from an axial symmetrical horn to a rectangular horn when the water acts as a cathode.

  16. Axial force measurement for esophageal function testing

    Gravesen, Flemming Holbæk; Funch-Jensen, Peter; Gregersen, Hans


    force transducers over in-vivo strain gauges of various sizes to electrical impedance based measurements. The amplitude and duration of the axial force has been shown to be as reliable as manometry. Normal, as well as abnormal, manometric recordings occur with normal bolus transit, which have been...... force (force in radial direction) whereas the bolus moves along the length of esophagus in a distal direction. Force measurements in the longitudinal (axial) direction provide a more direct measure of esophageal transport function. The technique used to record axial force has developed from external...... documented using imaging modalities such as radiography and scintigraphy. This inconsistency using manometry has also been documented by axial force recordings. This underlines the lack of information when diagnostics are based on manometry alone. Increasing the volume of a bag mounted on a probe...

  17. Axial Super-resolution Evanescent Wave Tomography

    Pendharker, Sarang; Newman, Ward; Ogg, Stephen; Nazemifard, Neda; Jacob, Zubin


    Optical tomographic reconstruction of a 3D nanoscale specimen is hindered by the axial diffraction limit, which is 2-3 times worse than the focal plane resolution. We propose and experimentally demonstrate an axial super-resolution evanescent wave tomography (AxSET) method that enables the use of regular evanescent wave microscopes like Total Internal Reflection Fluorescence Microscope (TIRF) beyond surface imaging, and achieve tomographic reconstruction with axial super-resolution. Our proposed method based on Fourier reconstruction achieves axial super-resolution by extracting information from multiple sets of three-dimensional fluorescence images when the sample is illuminated by an evanescent wave. We propose a procedure to extract super-resolution features from the incremental penetration of an evanescent wave and support our theory by 1D (along the optical axis) and 3D simulations. We validate our claims by experimentally demonstrating tomographic reconstruction of microtubules in HeLa cells with an axi...

  18. How to diagnose axial spondyloarthritis early

    Rudwaleit, M.; van der Heijde, D.; Khan, M.; Braun, J.; Sieper, J.


    Background: Chronic low back pain (LBP), the leading symptom of ankylosing spondylitis (AS) and undifferentiated axial spondyloarthritis (SpA), precedes the development of radiographic sacroiliitis, sometimes by many years.

  19. Axial thermal rotation of slender rods.

    Li, Dichuan; Fakhri, Nikta; Pasquali, Matteo; Biswal, Sibani Lisa


    Axial rotational diffusion of rodlike polymers is important in processes such as microtubule filament sliding and flagella beating. By imaging the motion of small kinks along the backbone of chains of DNA-linked colloids, we produce a direct and systematic measurement of axial rotational diffusivity of rods both in bulk solution and near a wall. The measured diffusivities decrease linearly with the chain length, irrespective of the distance from a wall, in agreement with slender-body hydrodynamics theory. Moreover, the presence of small kinks does not affect the chain's axial diffusivity. Our system and measurements provide insights into fundamental axial diffusion processes of slender objects, which encompass a wide range of entities including biological filaments and linear polymer chains.

  20. Nonperturbative Aspects of Axial Vector Vertex

    ZONG Hong-Shi; CHEN Xiang-Song; WANG Fan; CHANG Chao-Hsi; ZHAO En-Guang


    It is shown how the axial vector current of current quarks is related to that of constituent quarks within the framework of the global color symmetry model.Gluon dressing of the axial vector vertex and the quark self-energy functions are described by the inhomogeneous Bethe-Salpeter equation in the ladder approximation and the Schwinger Dyson equation in the rainbow approximation,respectively.

  1. Numerical simulation of axial flow compressors.

    Jesuino Takachi Tomita


    This work deals with the numerical simulation of axial flow compressors, from design to performance prediction. The stage performance prediction uses the meanline flow properties. Stage-stacking is used to analyse a multi-stage compressor. A computer program, written in FORTRAN, was developed and is able to design an axial flow compressor given air mass flow, total pressure ratio, overall efficiency and design speed. All geometrical data relevant to the compressor performance prediction is ca...

  2. Wave propagation in axially moving periodic strings

    Sorokin, Vladislav S.; Thomsen, Jon Juel


    The paper deals with analytically studying transverse waves propagation in an axially moving string with periodically modulated cross section. The structure effectively models various relevant technological systems, e.g. belts, thread lines, band saws, etc., and, in particular, roller chain drives for diesel engines by capturing both their spatial periodicity and axial motion. The Method of Varying Amplitudes is employed in the analysis. It is shown that the compound wave traveling in the axially moving periodic string comprises many components with different frequencies and wavenumbers. This is in contrast to non-moving periodic structures, for which all components of the corresponding compound wave feature the same frequency. Due to this "multi-frequency" character of the wave motion, the conventional notion of frequency band-gaps appears to be not applicable for the moving periodic strings. Thus, for such structures, by frequency band-gaps it is proposed to understand frequency ranges in which the primary component of the compound wave attenuates. Such frequency band-gaps can be present for a moving periodic string, but only if its axial velocity is lower than the transverse wave speed, and, the higher the axial velocity, the narrower the frequency band-gaps. The revealed effects could be of potential importance for applications, e.g. they indicate that due to spatial inhomogeneity, oscillations of axially moving periodic chains always involve a multitude of frequencies.

  3. An Unbroken Axial Vector Current Conservation Law

    Sharafiddinov, Rasulkhozha S


    The mass, energy and momentum of the neutrino of a true flavor have an axial-vector nature. As a consequence, the left-handed truly neutral neutrino in an axial-vector field of emission can be converted into a right-handed one and vice versa. This predicts the unidenticality of masses, energies and momenta of neutrinos of the different components. Recognizing such a difference in masses, energies, momenta and accepting that the left-handed axial-vector neutrino and the right-handed antineutrino of true neutrality refer to long-lived C-odd leptons, and the right-handed truly neutral neutrino and the left-handed axial-vector antineutrino are of short-lived fermions of C-oddity, we would write a new CP-even Dirac equation taking into account the flavor symmetrical axial-vector mass, energy and momentum matrices. Their presence explains the spontaneous mirror symmetry violation, confirming that an axial-vector current conservation law has never violated. They reflect the availability of a mirror Minkowski space i...

  4. Spatial Distribution of Regional Horizontal Deformations before and after the Yushu and Wenchuan Earthquakes%玉树和汶川地震前后区域水平形变的空间分布

    杨国华; 杨博; 占伟; 陈欣; 华彩虹; 王利


    Based on GNSS observation (from 1999 to 2007, and from 2009 to 2010) and continuous variation of deformation field, this study employed filtering and analysis of multi-kernel function and an unbiased algorithm of strain field to obtain movement and deformation field of the southeastern of Qinghai-Tibet Plateau before and after the Ms7.1 Yushu and Ms8. 0 Wenchuan earthquakes. The observations showed: ① Tectonic activities of seismic source were significantly weakened at spatial and relative long time level before the Yushu and Wenchuan earthquake. The maximum positive strain and shear strain fell to the lowest level of regional tectonic activities.②Spin shear deformation corresponding to the earthquake rupture was neither in nor far from the seismic source region, and there seemed an orderly coordinated action. The tectonic fault zone of Yushu earthquake was in the intermediate of regional right-lateral and left-lateral movements, while the largest stripe of left-lateral movement was 150 km away from the northeast of tectonic activity region, paralleling with the fault zone. Although structural fracture of Wenchuan earthquake was in the Longmen Mountain fault zone of right-lateral movement, the largest band of right-lateral movement was paralleled with this fault zone and in the northwestern activity zone with 200 km distance. ③The range of large co-seismic horizontal deformation of the Yushu earthquake was actually small, while the post-seismic horizontal deformation of the Wenchuan earthquake remains significant. ④ The North and the surrounding of Litang-Dewu fault zone should be given more attentions because plane-strain was presented in the image of quadrant distribution, and both the maximum positive strain and maximum shear strain were showing sign of being locked.%以1999-2007年和2009-2010年两个时间段的GNSS观测资料为基础,借助于多核函数解析、滤波和应变场的无偏算法以及区域无旋转基准,在运动场连续变化

  5. Modelling larval transport in a axial convergence front

    Robins, P.


    Marine larvae exhibit different vertical swimming behaviours, synchronised by factors such as tidal currents and daylight, in order to aid retention near the parent populations and hence promote production, avoid predation, or to stimulate digestion. This paper explores two types of larval migration in an estuarine axial convergent front which is an important circulatory mechanism in many coastal regions where larvae are concentrated. A parallelised, three-dimensional, ocean model was applied to an idealised estuarine channel which was parameterised from observations of an axial convergent front which occurs in the Conwy Estuary, U.K. (Nunes and Simpson, 1985). The model successfully simulates the bilateral cross-sectional recirculation of an axial convergent front, which has been attributed to lateral density gradients established by the interaction of the lateral shear of the longitudinal currents with the axial salinity gradients. On the flood tide, there is surface axial convergence whereas on the ebb tide, there is (weaker) surface divergence. Further simulations with increased/decreased tidal velocities and with stronger/weaker axial salinity gradients are planned so that the effects of a changing climate on the secondary flow can be understood. Three-dimensional Lagrangian Particle Tracking Models (PTMs) have been developed which use the simulated velocity fields to track larvae in the estuarine channel. The PTMs take into account the vertical migrations of two shellfish species that are commonly found in the Conwy Estuary: (i) tidal migration of the common shore crab (Carcinus maenas) and (ii), diel (daily) migration of the Great scallop (Pecten maximus). These migration behaviours are perhaps the most widespread amongst shellfish larvae and have been compared with passive (drifting) particles in order to assess their relative importance in terms of larval transport. Preliminary results suggest that the net along-estuary dispersal over a typical larval

  6. Relativistic quasiparticle random phase approximation in deformed nuclei

    Pena Arteaga, D.


    Covariant density functional theory is used to study the influence of electromagnetic radiation on deformed superfluid nuclei. The relativistic Hartree-Bogolyubov equations and the resulting diagonalization problem of the quasiparticle random phase approximation are solved for axially symmetric systems in a fully self-consistent way by a newly developed parallel code. Three different kinds of high precision energy functionals are investigated and special care is taken for the decoupling of the Goldstone modes. This allows the microscopic investigation of Pygmy and scissor resonances in electric and magnetic dipole fields. Excellent agreement with recent experiments is found and new types of modes are predicted for deformed systems with large neutron excess. (orig.)

  7. Microscopic derivation of nuclear rotation-vibration model, axially symmetric case

    Gulshani, Parviz


    We derive from first principles the successful phenomenological hydrodynamic model of Bohr-Davydov-Faessler-Greiner for rotation-vibration motion of an axially symmetric deformed nucleus. The derivation is not limited to small oscillation amplitude, and provides microscopic expressions for the interaction operators among the rotation, vibration, and intrinsic motions, for the moment of inertia, vibration mass, and for the deformation variables. The method uses canonical transformations to collective co-ordinates, followed by a constrained variational method, with the associated constraints imposed on the wavefunction rather than on the particle co-ordinates. The approach yields three self-consistent, time-reversal invariant, cranking-type Schrodinger equations for the rotation-vibration and intrinsic motions, and a self-consistency equation. For deformed harmonic oscillator mean-field potentials, these equations are solved in closed forms for the energies, moments of inertia, quadrupole moments and transition...

  8. Carbon nanotube heterojunctions: unusual deformations and mechanical vibration properties

    Scarpa, F.; Narojczyk, J.; Wojciechowski, K. W.; Inman, D. J.


    The mechanical deformation and dynamics properties of single wall carbon nanotube heterojunctions (HJ) oscillators are investigated using an hybrid finite element atomistic-continuum approach. The nanotube HJs provide a peculiar deformation pattern, with combined bending and axial stretching of carbon nanotubes (CNTs), and a broad agreement of their axial stiffness with spring series continuum mechanics and existing molecular dynamics (MD) simulations. We show also peculiar distributions of the natural frequencies and modes of the hetero-junctions compared to classical single-wall nanotube configurations, and the mass-sensor capability of (5,5)-(10,10) SWCNT HJ structures, with frequency shifts highly depending on the heterojunction section subjected to the mass loading.

  9. On the thermocapillary motion of deformable droplets

    Berejnov, V V


    In studies on Marangoni type motion of particles the surface tension is often approximated as a linear function of temperature. For deformable particles in a linear external temperature gradient far from the reference point this approximation yields a negative surface tension which is physically unrealistic. It is shown that H.Zhou and R.H.Davis J. Colloid Interface Sci., n.181,60,1996 presented calculation where the leading deformable drop moved into a region of negative surface tension. With respect numerical studies the restriction of the migration of two deformable drops is given in terms of the drift time.

  10. Ongoing Active Deformation Processes at Fernandina Volcano (Galapagos) Detected via Multi-Orbit COSMO-SkyMed SAR Data Analysis

    Pepe, Susi; Castaldo, Raffaele; De Luca, Claudio; Casu, Francesco; Tizzani, Pietro; Sansosti, Eugenio


    Fernandina Volcano, Galápagos (Ecuador), has experienced several uplift and eruption episodes over the last twenty-two years. The ground deformation between 2002 and 2006 was interpreted as the effect of an inflation phenomenon of two separate magma reservoirs beneath the caldera. Moreover, the uplift deformation occurred during the 2005 eruption was concentrated near the circumferential eruptive fissures, while being superimposed on a broad subsidence centred on the caldera. The geodetic studies emphasized the presence of two sub volcanic lateral intrusions from the central storage system in December 2006 and August 2007. The latest eruption in 2009 was characterized by lava flows emitted from the SW radial fissures. We analyze the spatial and temporal ground deformation between March 2012 and July 2013, by using data acquired by COSMO-SkyMed X-band constellation along both ascending and descending orbits and by applying advanced InSAR techniques. In particular, we use the SBAS InSAR approach and combine ascending and descending time series to produce vertical and East-West components of the mean deformation velocity and deformation time series. Our analysis revealed a new uplift phenomenon due to the stress concentration inside the shallow magmatic system of the volcano. In particular, the vertical mean velocity map shows that the deformation pattern is concentrated inside caldera region and is characterized by strongly radial symmetry with a maximum displacement of about 20 cm in uplift; an axial symmetry is also observed in the EW horizontal mean velocity map, showing a maximum displacement of about +12 cm towards East for the SE flank, and -12 cm towards West for the NW flank of the volcano. Moreover, the deformation time series show a rather linear uplift trend from March to September 2012, interrupted by a low deformation rate interval lasting until January 2013. After this stage, the deformation shows again a linear behaviour with an increased uplift rate

  11. High-resolution adaptive optics scanning laser ophthalmoscope with multiple deformable mirrors

    Chen, Diana C.; Olivier, Scot S.; Jones; Steven M.


    An adaptive optics scanning laser ophthalmoscopes is introduced to produce non-invasive views of the human retina. The use of dual deformable mirrors improved the dynamic range for correction of the wavefront aberrations compared with the use of the MEMS mirror alone, and improved the quality of the wavefront correction compared with the use of the bimorph mirror alone. The large-stroke bimorph deformable mirror improved the capability for axial sectioning with the confocal imaging system by providing an easier way to move the focus axially through different layers of the retina.

  12. Modeling of nonlinear multiaxial deformation of concrete on the base of hyperelastic orthotropic model

    Lavrov Kirill


    Full Text Available The hyperelastic orthotropic material model is proposed to describe the nonlinear behavior of concrete under monotonic multiaxial loading with taking into account the tension-compression anisotropy. The orthotropy is introduced for the correct description of concrete cracking. The hyperelasticity provides unconditional thermodynamical consistency and advantages in numerical solving of boundary value problems. Identification of model parameters is based on four experimental deformation diagrams of concrete: axial stress - axial strain and axial stress - transverse strain under uniaxial tension and compression. The results of the hyperelastic orthotropic model are compared with Karpenko’s orthotropic model and experimental data for multiaxial loading.

  13. -Deformed nonlinear maps

    Ramaswamy Jaganathan; Sudeshna Sinha


    Motivated by studies on -deformed physical systems related to quantum group structures, and by the elements of Tsallis statistical mechanics, the concept of -deformed nonlinear maps is introduced. As a specific example, a -deformation procedure is applied to the logistic map. Compared to the canonical logistic map, the resulting family of -logistic maps is shown to have a wider spectrum of interesting behaviours, including the co-existence of attractors – a phenomenon rare in one-dimensional maps.

  14. Alar Rim Deformities.

    Totonchi, Ali; Guyuron, Bahman


    The alar rim plays an important role in nasal harmony. Alar rim flaws are common following the initial rhinoplasty. Classification of the deformities helps with diagnosis and successful surgical correction. Diagnosis of the deformity requires careful observation of the computerized or life-sized photographs. Techniques for treatment of these deformities can easily be learned with attention to detail. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Melt Motion Due to Peltier Marking During Bridgman Crystal Growth with an Axial Magnetic Field

    Sellers, C. C.; Walker, John S.; Szofran, Frank R.; Motakef, Shariar


    This paper treats a liquid-metal flow inside an electrically insulating cylinder with electrically conducting solids above and below the liquid region. There is a uniform axial magnetic field, and there is an electric current through the liquid and both solids. Since the lower liquid-solid interface is concave into the solid and since the liquid is a better electrical conductor than the adjacent solid, the electric current is locally concentrated near the centerline. The return to a uniform current distribution involves a radial electric current which interacts with the axial magnetic field to drive an azimuthal flow. The axial variation of the centrifugal force due to the azimuthal velocity drives a meridional circulation with radial and axial velocities. This problem models the effects of Peltier marking during the vertical Bridgman growth of semiconductor crystals with an externally applied magnetic field, where the meridional circulation due to the Peltier Current may produce important mixing in the molten semiconductor.

  16. The Tip Leakage Flow Structure of an Axial Fan with Tip Clearance

    竺晓程; 杜朝辉; 林万来


    Experiment and numerical simulation technique are used to investigate the tip leakage flow in an axial fanwith tip clearance at the design condition. The flow field in the tip region of fan is measured using a PDA (ParticleDynamics Analysis) system. The flow is surveyed across the whole passage at fifteen axial locations (from the100% axial chord in front of the leading edge to the 100% axial chord behind the trailing edge), mainly focusing onthe outer 90% blade span. Both experiment measurement and numerical simulation indicates the leakage flow orig-inated from the tip clearance along the chord rolls-up into three-dimensional spiral structure to form leakage flowvortex. The interaction of leakage flow and main flow will produce the low velocity zone, and block the flow. Theleakage flow almost occupies the most part of flow passage behind the trailing edge.

  17. Posterior atlanto-occipital and atlanto-axial area and its surgical interest

    Newton José Godoy Pimenta


    Full Text Available Classic anatomical studies describe two membranes – atlanto-occipital and atlanto-axial in the posterior aspect of the craniocervical region. During many surgical procedures in this area, however, we have not found such membranes. Objective To clarify the anatomical aspects and structures taking part of the posterior atlanto-occipital and atlanto-axial area. Method Analysis of histological cuts of three human fetuses and anatomical studies of 8 adult human cadavers. Results In both atlanto-occipital and atlanto-axial areas, we have observed attachment between suboccipital deep muscles and the spinal cervical dura. However, anatomical description of such attachments could not be found in textbooks of anatomy. Conclusion Our study shows the absence of the classical atlanto-occipital and atlanto-axial membranes; the occipito-C1 and C1-C2 posterior intervals are an open area, allowing aponeurotic attachment among cervical dura mater and posterior cervical muscles.

  18. Fluctuations as stochastic deformation

    Kazinski, P. O.


    A notion of stochastic deformation is introduced and the corresponding algebraic deformation procedure is developed. This procedure is analogous to the deformation of an algebra of observables like deformation quantization, but for an imaginary deformation parameter (the Planck constant). This method is demonstrated on diverse relativistic and nonrelativistic models with finite and infinite degrees of freedom. It is shown that under stochastic deformation the model of a nonrelativistic particle interacting with the electromagnetic field on a curved background passes into the stochastic model described by the Fokker-Planck equation with the diffusion tensor being the inverse metric tensor. The first stochastic correction to the Newton equations for this system is found. The Klein-Kramers equation is also derived as the stochastic deformation of a certain classical model. Relativistic generalizations of the Fokker-Planck and Klein-Kramers equations are obtained by applying the procedure of stochastic deformation to appropriate relativistic classical models. The analog of the Fokker-Planck equation associated with the stochastic Lorentz-Dirac equation is derived too. The stochastic deformation of the models of a free scalar field and an electromagnetic field is investigated. It turns out that in the latter case the obtained stochastic model describes a fluctuating electromagnetic field in a transparent medium.

  19. Deformed discrete symmetries

    Arzano, Michele; Kowalski-Glikman, Jerzy


    We construct discrete symmetry transformations for deformed relativistic kinematics based on group valued momenta. We focus on the specific example of κ-deformations of the Poincaré algebra with associated momenta living on (a sub-manifold of) de Sitter space. Our approach relies on the description of quantum states constructed from deformed kinematics and the observable charges associated with them. The results we present provide the first step towards the analysis of experimental bounds on the deformation parameter κ to be derived via precision measurements of discrete symmetries and CPT.


    Jiang Songqing; Li Yongchi; Hu Xiuzhang; Zheng Jijia


    The Initial Imperfection Amplified Criterion is applied to investigate the geometric nonlinear dynamic buckling of statically preloaded ring-stiffened cylindrical shells under axial fluid-solid impact. Tak ing account of the effects of large deformation and initial geometric imperfection, the governing equations are obtained by the Galerkin method and solved by the Runge-Kutta method. The effects of static preloading (uniform external radial pressure) on the buckling features and the load-carrying ability of ring-stiffened cy lindrical shells against axial impact are discussed.

  1. Mathematical textbook of deformable neuroanatomies.

    Miller, M I; Christensen, G E; Amit, Y; Grenander, U


    Mathematical techniques are presented for the transformation of digital anatomical textbooks from the ideal to the individual, allowing for the representation of the variabilities manifest in normal human anatomies. The ideal textbook is constructed on a fixed coordinate system to contain all of the information currently available about the physical properties of neuroanatomies. This information is obtained via sensor probes such as magnetic resonance, as well as computed axial and emission tomography, along with symbolic information such as white- and gray-matter tracts, nuclei, etc. Human variability associated with individuals is accommodated by defining probabilistic transformations on the textbook coordinate system, the transformations forming mathematical translation groups of high dimension. The ideal is applied to the individual patient by finding the transformation which is consistent with physical properties of deformable elastic solids and which brings the coordinate system of the textbook to that of the patient. Registration, segmentation, and fusion all result automatically because the textbook carries symbolic values as well as multisensor features.

  2. Toward a Full Simulation of the Basic Oxygen Furnace: Deformation of the Bath Free Surface and Coupled Transfer Processes Associated with the Post-Combustion in the Gas Region

    Doh, Y.; Chapelle, P.; Jardy, A.; Djambazov, G.; Pericleous, K.; Ghazal, G.; Gardin, P.


    The present article treats different phenomena taking place in a steelmaking converter through the development of two separate models. The first model describes the cavity produced at the free surface of the metal bath by the high-speed impinging oxygen jet. The model is based on a zonal approach, where gas compressibility effects are taken into account only in the high velocity jet region, while elsewhere the gas is treated as incompressible. The volume of fluid (VOF) method is employed to follow the deformation of the bath free surface. Calculations are presented for two- and three-phase systems and compared against experimental data obtained in a cold model experiment presented in the literature. The influence on the size and shape of the cavity of various parameters and models (including the jet inlet boundary conditions, the VOF advection scheme, and the turbulence model) is studied. Next, the model is used to simulate the interaction of a supersonic oxygen jet with the surface of a liquid steel bath in a pilot-scale converter. The second model concentrates on fluid flow, heat transfer, and the post-combustion reaction in the gas phase above the metal bath. The model uses the simple chemical reaction scheme approach to describe the transport of the chemical species and takes into account the consumption of oxygen by the bath and thermal radiative transfer. The model predictions are in reasonable agreement with measurements collected in a laboratory experiment and in a pilot-scale furnace.

  3. 2000 Squaw Creek National Wildlife Refuge Amphibian Deformity Monitoring Report

    US Fish and Wildlife Service, Department of the Interior — In 1997 the Region 3 Assistant Regional Director (ARD) requested that all staffed field stations conduct amphibian deformity surveys. The purpose of these surveys...

  4. 2001 Squaw Creek National Wildlife Refuge Amphibian Deformity Monitoring Report

    US Fish and Wildlife Service, Department of the Interior — In 1997 the Region 3 Assistant Regional Director (ARD) requested that all staffed field stations conduct amphibian deformity surveys. The purpose of these surveys...

  5. 2002 Squaw Creek National Wildlife Refuge Amphibian Deformity Monitoring Report

    US Fish and Wildlife Service, Department of the Interior — In 1997 the Region 3 Assistant Regional Director (ARD) requested that all staffed field stations conduct amphibian deformity surveys. The purpose of these surveys...

  6. 2003 Squaw Creek National Wildlife Refuge Amphibian Deformity Monitoring Report

    US Fish and Wildlife Service, Department of the Interior — In 1997 the Region 3 Assistant Regional Director (ARD) requested that all staffed field stations conduct amphibian deformity surveys. The purpose of these surveys...

  7. Optimization of residual heat removal pump axial thrust and axial bearing

    Schubert, F.


    The residual heat removal (RHR) pumps of German 1300 megawatt pressurized-water reactor (PWR) power plants are of the single stage end suction type with volute casing or with diffuser and forged circular casing. Due to the service conditions the pumps have to cover the full capacity range as well as a big variation in suction static pressure. This results in a big difference in the axial thrust that has to be borne by the axial bearing. Because these pumps are designed to operate without auxiliary systems (things that do not exist can not fail), they are equipped with antifriction bearings and sump oil lubrication. To minimize the heat production within the bearing casing, a number of PWR plants have pumps with combined axial/radial bearings of the ball type. Due to the fact that the maximum axial thrust caused by static pressure and hydrodynamic forces on the impeller is too big to be borne by that type of axial bearing, the impellers were designed to produce a hydrodynamic axial force that counteracts the static axial force. Thus, the resulting axial thrust may change direction when the static pressure varies.

  8. Reducing axial mixing in flotation columns

    Al Taweel, A.M.; Ramadan, A.M. [Technical Univ. of Nova Scotia, Halifax (Canada). Chemical Engineering Dept.; Moharam, M.R.; Hassan, T.A. [Al Azhar Univ., Cairo (Egypt); El Mofty, S.M. [Cairo Univ., Giza (Egypt)


    The axial mixing characteristics of a pilot-scale flotation column were investigated with the objective of identifying means to mitigate the extent of axial mixing that adversely affects its grade/recovery performance. A wide range of design and operating conditions wa investigated and the experimental results, obtained using the dynamic response method, were analyzed using three axial mixing models. The dynamic response of the column can best be described using the axial dispersion model. The results obtained suggest that the value of the axial dispersion coefficient, E{sub L}, can be significantly reduced by judicial selection of hydrodynamic conditions and/or the use of column inserts that suppress the onset of hydrodynamic instabilities inherent to the operation of conventional flotation columns. Up to 40% reduction in the value of E{sub L} was thus obtained by using spargers that produce more uniform bubble sizes, while up to 30% reductions were obtained by controlling the residual frother concentration. 33 refs., 7 figs.

  9. Axial super-resolution evanescent wave tomography.

    Pendharker, Sarang; Shende, Swapnali; Newman, Ward; Ogg, Stephen; Nazemifard, Neda; Jacob, Zubin


    Optical tomographic reconstruction of a three-dimensional (3D) nanoscale specimen is hindered by the axial diffraction limit, which is 2-3 times worse than the focal plane resolution. We propose and experimentally demonstrate an axial super-resolution evanescent wave tomography method that enables the use of regular evanescent wave microscopes like the total internal reflection fluorescence microscope beyond surface imaging and achieve a tomographic reconstruction with axial super-resolution. Our proposed method based on Fourier reconstruction achieves axial super-resolution by extracting information from multiple sets of 3D fluorescence images when the sample is illuminated by an evanescent wave. We propose a procedure to extract super-resolution features from the incremental penetration of an evanescent wave and support our theory by one-dimensional (along the optical axis) and 3D simulations. We validate our claims by experimentally demonstrating tomographic reconstruction of microtubules in HeLa cells with an axial resolution of ∼130  nm. Our method does not require any additional optical components or sample preparation. The proposed method can be combined with focal plane super-resolution techniques like stochastic optical reconstruction microscopy and can also be adapted for THz and microwave near-field tomography.

  10. Axial super-resolution evanescent wave tomography

    Pendharker, Sarang; Shende, Swapnali; Newman, Ward; Ogg, Stephen; Nazemifard, Neda; Jacob, Zubin


    Optical tomographic reconstruction of a 3D nanoscale specimen is hindered by the axial diffraction limit, which is 2-3 times worse than the focal plane resolution. We propose and experimentally demonstrate an axial super-resolution evanescent wave tomography (AxSET) method that enables the use of regular evanescent wave microscopes like Total Internal Reflection Fluorescence Microscope (TIRF) beyond surface imaging, and achieve tomographic reconstruction with axial super-resolution. Our proposed method based on Fourier reconstruction achieves axial super-resolution by extracting information from multiple sets of three-dimensional fluorescence images when the sample is illuminated by an evanescent wave. We propose a procedure to extract super-resolution features from the incremental penetration of an evanescent wave and support our theory by 1D (along the optical axis) and 3D simulations. We validate our claims by experimentally demonstrating tomographic reconstruction of microtubules in HeLa cells with an axial resolution of $\\sim$130 nm. Our method does not require any additional optical components or sample preparation. The proposed method can be combined with focal plane super-resolution techniques like STORM and can also be adapted for THz and microwave near-field tomography.

  11. Evaluation of the performance and flow in an axial compressor

    Waddell, J. L.


    An experimental evaluation of the axial compressor test rig with one stage of symmetric blading was conducted to determine its suitability for studies of tip clearance effects. Measurements were made of performance parameters and internal flow fields. The configuration tested was found to be unsuitable due to poor flow from the inlet guide vanes, particularly near the tip region. Secondary flows and flaws in construction of the guide vanes were suggested as probable causes. Recommendations were made for a program to resolve the problem.

  12. Parametric design of tri-axial nested Helmholtz coils.

    Abbott, Jake J


    This paper provides an optimal parametric design for tri-axial nested Helmholtz coils, which are used to generate a uniform magnetic field with controllable magnitude and direction. Circular and square coils, both with square cross section, are considered. Practical considerations such as wire selection, wire-wrapping efficiency, wire bending radius, choice of power supply, and inductance and time response are included. Using the equations provided, a designer can quickly create an optimal set of custom coils to generate a specified field magnitude in the uniform-field region while maintaining specified accessibility to the central workspace. An example case study is included.

  13. Axial-torsional fatigue - A study of tubular specimen thickness effects

    Bonacuse, Peter J.; Kalluri, Sreeramesh


    Experiments were carried out at room temperature on AISI type 316 stainless steel to determine the effect of wall thickness on the cyclic deformation behavior and fatigue life of thin-wall tubular axial-torsional fatigue specimens. The experimental variables examined included the depth of the surface work-hardened layer produced in specimen machining, and the effects of strain range and axial-torsional strain phasing. Tubular fatigue specimens had wall thicknesses of 1.5, 2.0, and 2.5 mm. One as-fabricated specimen from each wall thickness was sectioned for microstructural examination and microhardness measurement. A specimen of each wall thickness was tested in axial-torsional fatigue experiments for each of the three conditions: high strain range in-phase, low strain range in-phase, and low strain range out-of-phase. The machining-induced work-hardened zone, as a percentage of the gage section material, was found to have a minimal effect on both deformation behavior and fatigue life. Out-of-phase fatigue tests displayed shorter fatigue lives and more cyclic hardening than in-phase tests.


    瞿伟; 王庆良; 张勤; 张明


    On the basis of the "digital seismic network engineering" GPS monitoring results, and combined with regional tectonic features,the 2D finite element model of the Weihe basin central region is built. According to the above, the present crustal deformation-strain distribution characteristics of the studied area are obtained. The results show that the Xi' an-Xianyang area is of significantly high value of the surface expansion and mainly tensile strain within the area, the value respectively reaches more than 2. 0 × 10-6 /a and 3.5×10-6/a. Thus the present crustal tensile tectonic activity of Xi' an-Xianyang area is strong.%基于中国地壳运动观测网络工程项目的GPS监测成果,结合区域构造特点构建了渭河盆地中部区域二维有限元模型,以此获取了该区域现今地壳形变-应变分布特征.结果表明:该区域内西安、咸阳地区是面膨胀及主张应变显著高值区,量值分别为2.0×10-6/a及3.5×10-6/a,说明西安、咸阳地区现今地壳拉张构造活动较强烈.

  15. Intracrystalline deformation of calcite

    de Bresser, Hans


    It is well established from observations on natural calcite tectonites that intracrystalline plastic mechanisms are important during the deformation of calcite rocks in nature. In this thesis, new data are presented on fundamental aspects of deformation behaviour of calcite under conditions where 'd

  16. Resurgent deformation quantisation

    Garay, Mauricio, E-mail: [Institut für Mathematik, FB 08 Physik, Mathematik und Informatik, Johannes Gutenberg-Universität, 55099 Mainz (Germany); Goursac, Axel de, E-mail: [Chargé de Recherche au F.R.S.-FNRS, IRMP, Université Catholique de Louvain, Chemin du Cyclotron, 2, B-1348 Louvain-la-Neuve (Belgium); Straten, Duco van, E-mail: [Institut für Mathematik, FB 08 Physik, Mathematik und Informatik, Johannes Gutenberg-Universität, 55099 Mainz (Germany)


    We construct a version of the complex Heisenberg algebra based on the idea of endless analytic continuation. The algebra would be large enough to capture quantum effects that escape ordinary formal deformation quantisation. -- Highlights: •We construct resurgent deformation quantisation. •We give integral formulæ. •We compute examples which show that hypergeometric functions appear naturally in quantum computations.

  17. Influencing Factors of Thermal Deformation on Hydrostatic Pressure Mechanical Seal and Optimization of Rotating and Stationary Rings

    Lin Dong


    Full Text Available According to thermo-elastic deformation theory, take the temperature field analysis results of hydrostatic pressure mechanical seal as volume load to resolve the problem of thermal-structure coupling deformation of rotating and stationary rings in ANSYS software. The distribution laws of thermal strain, thermal stress and thermal-structure coupling deformation are obtained. The effects of working, material and structural parameters on axial, radial thermal deformation and deformation taper of the end faces are discussed in detail, and the main affecting factors are found out. Measures and structural constraint programs to control the thermal deformation are put forward. Base on the theory of thermal deformation compensation, the rotating and stationary rings are optimized, and the thermal deformation before and after their optimization are solved respectively and analyzed comparatively to verify the feasibility of the optimization program.

  18. Effect of multiaxial deformation Max-strain on the structure and properties of Ti-Ni alloy

    Khmelevskaya, I. Yu; Kawalla, R.; Prokoshkin, S. D.; Komarov, V. S.


    The severe plastic deformation (SPD) forming ultrafine-grained (nanocrystalline or nanosubgrained) structure is one of the most effective ways to improve the functional properties of Ti-Ni-based shape memory alloys [1, 2]. In the present work, the SPD of near-equiatomic Ti-Ni alloy was carried out using the multi-axial deformation module Max-strain, which is a part of the physical simulation system "Gleeble 3500". The deformation was performed at a constant temperature of 400°C with speed of 0.5 mm/s in six passes without interpass pauses. The accumulated true strain was about 3. As a result, a mixed ultrafine-grained/subgrained structure with grain/subgrain sizes from 50 to 300 nm and a high density of free dislocations formed. The resulting structure is close to a nanoscale region and provides a significant advantage in the basic functional property - completely recoverable strain - as compared with a conventional recrystallized structure: 7% versus 2%.

  19. Deformations of Superconformal Theories

    Cordova, Clay; Intriligator, Kenneth


    We classify possible supersymmetry-preserving relevant, marginal, and irrelevant deformations of unitary superconformal theories in $d \\geq 3$ dimensions. Our method only relies on symmetries and unitarity. Hence, the results are model independent and do not require a Lagrangian description. Two unifying themes emerge: first, many theories admit deformations that reside in multiplets together with conserved currents. Such deformations can lead to modifications of the supersymmetry algebra by central and non-central charges. Second, many theories with a sufficient amount of supersymmetry do not admit relevant or marginal deformations, and some admit neither. The classification is complicated by the fact that short superconformal multiplets display a rich variety of sporadic phenomena, including supersymmetric deformations that reside in the middle of a multiplet. We illustrate our results with examples in diverse dimensions. In particular, we explain how the classification of irrelevant supersymmetric deformat...

  20. Massey products and deformations

    Fuchs, D; Fuchs, Dmitry; Lang, Lynelle


    The classical deformation theory of Lie algebras involves different kinds of Massey products of cohomology classes. Even the condition of extendibility of an infinitesimal deformation to a formal one-parameter deformation of a Lie algebra involves Massey powers of two dimensional cohomology classes which are not powers in the usual definition of Massey products in the cohomology of a differential graded Lie algebra. In the case of deformations with other local bases, one deals with other, more specific Massey products. In the present work a construction of generalized Massey products is given, depending on an arbitrary graded commutative, associative algebra. In terms of these products, the above condition of extendibility is generalized to deformations with arbitrary local bases. Dually, a construction of generalized Massey products on the cohomology of a differential graded commutative associative algebra depends on a nilpotent graded Lie algebra. For example, the classical Massey products correspond to the...

  1. Atlanto-axial infection after acupuncture.

    Robinson, A; Lind, C R P; Smith, R J; Kodali, V


    A 67-year-old man presented with neck cellulitis following acupuncture for cervical spondylosis. Blood cultures were positive for methicillin-sensitive Staphylococcus aureus. Increased neck pain and bacteraemia prompted MRI, which showed atlanto-axial septic arthritis without signs of infection of the tissues between the superficial cellulitic area and the atlanto-axial joint, thus making direct extension of infection unlikely. It is more likely that haematogenous spread of infection resulted in seeding in the atlanto-axial joint, with the proximity of the arthritis and acupuncture site being coincidental. Acupuncture is a treatment option for some indolent pain conditions. As such, acupuncture services are likely to be more frequently utilised. A history of acupuncture is rarely requested by the admitting doctor and seldom offered voluntarily by the patient, especially where the site of infection due to haematogenous spread is distant from the needling location. Awareness of infectious complications following acupuncture can reduce morbidity through early intervention.

  2. Axial symmetry and conformal Killing vectors

    Mars, M; Mars, Marc; Senovilla, Jose M.M.


    Axisymmetric spacetimes with a conformal symmetry are studied and it is shown that, if there is no further conformal symmetry, the axial Killing vector and the conformal Killing vector must commute. As a direct consequence, in conformally stationary and axisymmetric spacetimes, no restriction is made by assuming that the axial symmetry and the conformal timelike symmetry commute. Furthermore, we prove that in axisymmetric spacetimes with another symmetry (such as stationary and axisymmetric or cylindrically symmetric spacetimes) and a conformal symmetry, the commutator of the axial Killing vector with the two others mush vanish or else the symmetry is larger than that originally considered. The results are completely general and do not depend on Einstein's equations or any particular matter content.

  3. Axial flow positive displacement worm gas generator

    Murrow, Kurt David (Inventor); Giffin, Rollin George (Inventor); Fakunle, Oladapo (Inventor)


    An axial flow positive displacement engine has an inlet axially spaced apart and upstream from an outlet. Inner and outer bodies have offset inner and outer axes extend from the inlet to the outlet through first, second, and third sections of a core assembly in serial downstream flow relationship. At least one of the bodies is rotatable about its axis. The inner and outer bodies have intermeshed inner and outer helical blades wound about the inner and outer axes respectively. The inner and outer helical blades extend radially outwardly and inwardly respectively. The helical blades have first, second, and third twist slopes in the first, second, and third sections respectively. The first twist slopes are less than the second twist slopes and the third twist slopes are less than the second twist slopes. A combustor section extends axially downstream through at least a portion of the second section.

  4. Improving the lattice axial vector current

    Horsley, R. [Edinburgh Univ. (United Kingdom). School of Physics and Astronomy; Nakamura, Y. [RIKEN Advanced Institute for Computational Science, Kobe (Japan); Perlt, H.; Schiller, A. [Leipzig Univ. (Germany). Inst. fuer Theoretische Physik; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Div.; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Zanotti, J.M. [Adelaide Univ. (Australia). CSSM, Dept. of Physics


    For Wilson and clover fermions traditional formulations of the axial vector current do not respect the continuum Ward identity which relates the divergence of that current to the pseudoscalar density. Here we propose to use a point-split or one-link axial vector current whose divergence exactly satisfies a lattice Ward identity, involving the pseudoscalar density and a number of irrelevant operators. We check in one-loop lattice perturbation theory with SLiNC fermion and gauge plaquette action that this is indeed the case including order O(a) effects. Including these operators the axial Ward identity remains renormalisation invariant. First preliminary results of a nonperturbative check of the Ward identity are also presented.

  5. Organocatalytic atroposelective synthesis of axially chiral styrenes

    Zheng, Sheng-Cai; Wu, San; Zhou, Qinghai; Chung, Lung Wa; Ye, Liu; Tan, Bin


    Axially chiral compounds are widespread in biologically active compounds and are useful chiral ligands or organocatalysts in asymmetric catalysis. It is well-known that styrenes are one of the most abundant and principal feedstocks and thus represent excellent prospective building blocks for chemical synthesis. Driven by the development of atroposelective synthesis of axially chiral styrene derivatives, we discovered herein the asymmetric organocatalytic approach via direct Michael addition reaction of substituted diones/ketone esters/malononitrile to alkynals. The axially chiral styrene compounds were produced with good chemical yields, enantioselectivities and almost complete E/Z-selectivities through a secondary amine-catalysed iminium activation strategy under mild conditions. Such structural motifs are important precursors for further transformations into biologically active compounds and synthetic useful intermediates and may have potential applications in asymmetric synthesis as olefin ligands or organocatalysts.

  6. Improving the lattice axial vector current

    Horsley, R; Perlt, H; Rakow, P E L; Schierholz, G; Schiller, A; Zanotti, J M


    For Wilson and clover fermions traditional formulations of the axial vector current do not respect the continuum Ward identity which relates the divergence of that current to the pseudoscalar density. Here we propose to use a point-split or one-link axial vector current whose divergence exactly satisfies a lattice Ward identity, involving the pseudoscalar density and a number of irrelevant operators. We check in one-loop lattice perturbation theory with SLiNC fermion and gauge plaquette action that this is indeed the case including order $O(a)$ effects. Including these operators the axial Ward identity remains renormalisation invariant. First preliminary results of a nonperturbative check of the Ward identity are also presented.

  7. Craniofacial neurofibromatosis: treatment of the midface deformity.

    Singhal, Dhruv; Chen, Yi-Chieh; Tsai, Yueh-Ju; Yu, Chung-Chih; Chen, Hung Chang; Chen, Yu-Ray; Chen, Philip Kuo-Ting


    Craniofacial Neurofibromatosis is a benign but devastating disease. While the most common location of facial involvement is the orbito-temporal region, patients often present with significant mid-face deformities. We reviewed our experience with Craniofacial Neurofibromatosis from June 1981 to June 2011 and included patients with midface soft tissue deformities defined as gross alteration of nasal or upper lip symmetry. Data reviewed included the medical records and photobank. Over 30 years, 52 patients presented to and underwent surgical management for Craniofacial Neurofibromatosis at the Chang Gung Craniofacial Center. 23 patients (43%) demonstrated gross mid-facial deformities at initial evaluation. 55% of patients with lip deformities and 28% of patients with nasal deformities demonstrated no direct tumour involvement. The respective deformity was solely due to secondary gravitational effects from neurofibromas of the cheek subunit. Primary tumour infiltration of the nasal and/or labial subunits was treated with excision followed by various methods of reconstruction including lower lateral cartilage repositioning, forehead flaps, free flaps, and/or oral commissure suspension. Soft tissue deformities of the midface are very common in patients with Craniofacial Neurofibromatosis and profoundly affect overall aesthetic outcomes. Distinguishing primary from secondary involvement of the midface assists in surgical decision making. Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  8. Axial loaded MRI of the lumbar spine

    Saifuddin, A. E-mail:; Blease, S.; MacSweeney, E


    Magnetic resonance imaging is established as the technique of choice for assessment of degenerative disorders of the lumbar spine. However, it is routinely performed with the patient supine and the hips and knees flexed. The absence of axial loading and lumbar extension results in a maximization of spinal canal dimensions, which may in some cases, result in failure to demonstrate nerve root compression. Attempts have been made to image the lumbar spine in a more physiological state, either by imaging with flexion-extension, in the erect position or by using axial loading. This article reviews the literature relating to the above techniques.

  9. Water Ingestion Into Axial Flow Compressors


    AFAPL-TR-76-77 WATER INGESTION INTO AXIAL FLOW COMPRESSORS PURDUE UNIVERSITY SCHOOL OF AERONAUTICS AND ASTRONA UTICS S WEST LAFAYETTE, INDIANA 47907...CIPIENT’S CATALOG NUMBER TITL _07" 0 EREO Final i-7 0 Water Ingestion Into Axial Flow Compressorse 1 Auq 75 -: 31 Au0 a6 114o’ H-WPAFB-T-76-l:P ."CO TACT...necessary and Idenify by block number) Water ingestion , turbomachinery, and jet engines. 20 ABSTRACT (Contlinue on tov.ras side Hi necessary and Identify


    Sh. F. Erdes


    Full Text Available The clear definition of the concept of «flare in axial spondyloarthritis» is of paramount importance for clinical trials and routine practice in particular. It will be able to unify the characteristics of outcomes over a particular period of time on the one hand and to standardize therapeutic approaches on the other. On 4 February 2016, the journal Annals of Rheumatic Diseases published the on-line paper «Preliminary definitions of 'flare' in axial spondyloarthritis, based on pain, BASDAI and ASDAS-CRP: an ASAS initiative» by L. Gossec et al., which was devoted to this topic.

  11. Optimization of Axial Intensity Point Spread Function

    WANG Haifeng; GAN Fuxi; CHEN Zhongyu


    It is known that for the converged laser beam, the axial intensity distribution corresponds to a Gaussian curve, that is, the intensity on the focal plane is the peak intensity. When it defocuses, the intensity would decrease rapidly. In optical data storage, for instance, we expect the intensity within a certain distance to be almost equal. In this paper, we propose to use a pure phase superresolution apodizer to optimize the axial intensity distribution of the converged laser beam and at the same time improve the resolution. The intensity point spread function remains almost identical in a wide range within the focal depth.

  12. Axial Nucleon form factors from lattice QCD

    Alexandrou, C; Carbonell, J; Constantinou, M; Harraud, P A; Guichon, P; Jansen, K; Korzec, T; Papinutto, M


    We present results on the nucleon axial form factors within lattice QCD using two flavors of degenerate twisted mass fermions. Volume effects are examined using simulations at two volumes of spatial length $L=2.1$ fm and $L=2.8$ fm. Cut-off effects are investigated using three different values of the lattice spacings, namely $a=0.089$ fm, $a=0.070$ fm and $a=0.056$ fm. The nucleon axial charge is obtained in the continuum limit and chirally extrapolated to the physical pion mass enabling comparison with experiment.

  13. Axial Vircator for Electronic Warfare Applications

    L. Drazan


    Full Text Available This paper deals with a high power microwave generator with virtual cathode – vircator in axial release for electronic warfare applications. The classification of directed energy weapons microwave (DEWM is introduced together with basic block diagrams of a particular class of DEWM. In the paper, methods for designing vircator pulsed power supply, axial vircator structure, measurement methods and experimental results are presented. The vircator in electromagnetic ammunition is powered by magneto-cumulative generator and in weapons for defense of objects (WDO, it is powered by Marx generator. The possible applications of a vircator in the DEWM area are discussed.

  14. Survey of Reflection-Asymmetric Nuclear Deformations

    Olsen, Erik; Cao, Yuchen; Nazarewicz, Witold; Schunck, Nicolas


    Due to spontaneous symmetry breaking it is possible for a nucleus to have a deformed shape in its ground state. It is theorized that atoms whose nuclei have reflection-asymmetric or pear-like deformations could have non-zero electric dipole moments (EDMs). Such a trait would be evidence of CP-violation, a feature that goes beyond the Standard Model of Physics. It is the purpose of this project to predict which nuclei exhibit a reflection-asymmetric deformation and which of those would be the best candidates for an EDM measuring experiment. Using nuclear Density Functional Theory along with the new computer code AxialHFB and massively parallel computing we calculated ground state nuclear properties for thousands of even-even nuclei across the nuclear chart: from light to superheavy and from stable to short-lived systems. Six different Energy Density Functionals (EDFs) were used to assess systematic errors in our calculations. These results are to be added to the website Massexplorer ( which contains results from earlier mass table calculations and information on single quasiparticle energies.

  15. Experimental and Numerical Investigation of an Axial Rotary Blood Pump.

    Schüle, Chan Yong; Thamsen, Bente; Blümel, Bastian; Lommel, Michael; Karakaya, Tamer; Paschereit, Christian Oliver; Affeld, Klaus; Kertzscher, Ulrich


    Left ventricular assist devices (LVADs) have become a standard therapy for patients with severe heart failure. As low blood trauma in LVADs is important for a good clinical outcome, the assessment of the fluid loads inside the pump is critical. More specifically, the flow features on the surfaces where the interaction between blood and artificial material happens is of great importance. Therefore, experimental data for the near-wall flows in an axial rotary blood pump were collected and directly compared to computational fluid dynamic results. For this, the flow fields based on unsteady Reynolds-averaged Navier-Stokes simulations-computational fluid dynamics (URANS-CFD) of an axial rotary blood pump were calculated and compared with experimental flow data at one typical state of operation in an enlarged model of the pump. The focus was set on the assessment of wall shear stresses (WSS) at the housing wall and rotor gap region by means of the wall-particle image velocimetry technique, and the visualization of near-wall flow structures on the inner pump surfaces by a paint erosion method. Additionally, maximum WSS and tip leakage volume flows were measured for 13 different states of operation. Good agreement between CFD and experimental data was found, which includes the location, magnitude, and direction of the maximum and minimum WSS and the presence of recirculation zones on the pump stators. The maximum WSS increased linearly with pressure head. They occurred at the upstream third of the impeller blades and exceeded the critical values with respect to hemolysis. Regions of very high shear stresses and recirculation zones could be identified and were in good agreement with simulations. URANS-CFD, which is often used for pump performance and blood damage prediction, seems to be, therefore, a valid tool for the assessment of flow fields in axial rotary blood pumps. The magnitude of maximum WSS could be confirmed and were in the order of several hundred Pascal.

  16. Axial-vector dominance predictions in quasielastic neutrino-nucleus scattering

    Amaro, J. E.; Ruiz Arriola, E.


    The axial form factor plays a crucial role in quasielastic neutrino-nucleus scattering, but the error of the theoretical cross section due to uncertainties of GA remains to be established. Conversely, the extraction of GA from the neutrino nucleus cross section suffers from large systematic errors due to nuclear model dependencies, while the use of single-parameter dipole fits underestimates the errors and prevents an identification of the relevant kinematics for this determination. We propose to use a generalized axial-vector-meson dominance in conjunction with large-Nc and high-energy QCD constraints to model the nucleon axial form factor, as well as the half-width rule as an a priori uncertainty estimate. The minimal hadronic ansatz comprises the sum of two monopoles corresponding to the lightest axial-vector mesons being coupled to the axial current. The parameters of the resulting axial form factor are the masses and widths of the two axial mesons as obtained from the averaged Particle Data Group values. By applying the half-width rule in a Monte Carlo simulation, a distribution of theoretical predictions can then be generated for the neutrino-nucleus quasielastic cross section. We test the model by applying it to the (νμ,μ ) quasielastic cross section from 12 for the kinematics of the MiniBooNE experiment. The resulting predictions have no free parameters. We find that the relativistic Fermi gas model globally reproduces the experimental data, giving χ2/# bins=0.81 . A Q2-dependent error analysis of the neutrino data shows that the uncertainties in the axial form factor GA(Q2) are comparable to the ones induced by the a priori half-width rule. We identify the most sensitive region to be in the range 0.2 ≲Q2≲0.6 GeV2 .




    Full Text Available Empty and water filled cylindrical Tin (Sn coated steel cans were loaded under axial compression at varying loading rates to study their resistance to withstand accidental loads. Compared to empty cans the water filled cans exhibit greater resistance to axially applied compression loads before a complete collapse. The time and load or stroke and load plots showed three significant load peaks related to three stages during loading until the cylinder collapse. First peak corresponds to the initial structural buckling of can. Second peak occurs when cylindrical can walls gradually come into full contact with water. The third peak shows the maximum load carrying capability of the structure where pressurized water deforms the can walls into curved shape until can walls fail under peak pressure. The collapse process of water filled cylindrical shell was further studied using Smooth Particle Hydrodynamics (SPH technique in LSDYNA. Load peaks observed in the experimental work were successfully simulated which substantiated the experimental work.

  18. Computationally Informed Design of a Multi-Axial Actuated Microfluidic Chip Device.

    Gizzi, Alessio; Giannitelli, Sara Maria; Trombetta, Marcella; Cherubini, Christian; Filippi, Simonetta; De Ninno, Adele; Businaro, Luca; Gerardino, Annamaria; Rainer, Alberto


    This paper describes the computationally informed design and experimental validation of a microfluidic chip device with multi-axial stretching capabilities. The device, based on PDMS soft-lithography, consisted of a thin porous membrane, mounted between two fluidic compartments, and tensioned via a set of vacuum-driven actuators. A finite element analysis solver implementing a set of different nonlinear elastic and hyperelastic material models was used to drive the design and optimization of chip geometry and to investigate the resulting deformation patterns under multi-axial loading. Computational results were cross-validated by experimental testing of prototypal devices featuring the in silico optimized geometry. The proposed methodology represents a suite of computationally handy simulation tools that might find application in the design and in silico mechanical characterization of a wide range of stretchable microfluidic devices.

  19. Study on Interaction Relationship for Submarine Pipeline with Axial Corrosion Defects

    CHEN Yan-fei; LI Xin; ZHOU Jing; GUAN Jiong


    Corrosion is one of the main reasons to cause the operation accident of submarine oil and gas transmission pipelines. As the major corrosion pattern in submarine pipelines, the effects of corrosion clusters consisting of the adjacent corrosion defects on failure pressure are investigated through non-linear large-deformation finite element method. Typically, the failure behavior and limit strength of submarine pipeline with axial groove-groove corrosion defect pair exposed to internal pressure are analyzed. The effects of corrosion depth and axial spacing between a pair of corrosion defects on failure pressure are concluded. An interaction relationship for corrosion defects in pipelines, as well as prediction formulations for assessing the remaining strength of corroded pipelines are proposed. The expressions based on the proposed interaction relationship give more accurate results than the methods used in the existing design guidelines.

  20. The Spherical Deformation Model

    Hobolth, Asgar


    Miller et al. (1994) describe a model for representing spatial objects with no obvious landmarks. Each object is represented by a global translation and a normal deformation of a sphere. The normal deformation is defined via the orthonormal spherical-harmonic basis. In this paper we analyse...... the spherical deformation model in detail and describe how it may be used to summarize the shape of star-shaped three-dimensional objects with few parameters. It is of interest to make statistical inference about the three-dimensional shape parameters from continuous observations of the surface and from...

  1. Calcaneo-valgus deformity.

    Evans, D


    A discussion of the essential deformity in calcaneo-valgus feet develops a theme originally put forward in 1961 on the relapsed club foot (Evans 1961). Whereas in the normal foot the medial and lateral columns are about equal in length, in talipes equino-varus the lateral column is longer and in calcaneo-valgus shorter than the medial column. The suggestion is that in the treatment of both deformities the length of the columns be made equal. A method is described of treating calcaneo-valgus deformity by inserting cortical bone grafts taken from the tibia to elongate the anterior end of the calcaneus.

  2. Suppression of Rayleigh-Taylor instability by gyroviscosity and sheared axial flow in imploding plasma pinches

    HUANG Lin; JIAN Guang-de; QIU Xiao-ming


    The synergistic stabilizing effect of gyroviscosity and sheared axial flow on the Rayleigh-Taylor instability in Z-pinch implosions is studied by means of the incompressible viscid magneto-hydrodynamic equations. The gyroviscosity (or finite Larmor radius) effects are introduced in the momentum equation through an anisotropic ion stress tensor. Dispersion relation with the effect of a density discontinuity is derived. The results indicate that the short-wavelength modes of the Rayleigh-Taylor instability are easily stabilized by the gyroviscosity effects. The long wavelength modes are stabilized by the sufficient sheared axial flow. However, the synergistic effects of the finite Larmor radius and sheared axial flow can heavily mitigate the Rayleigh-Taylor instability. This synergistic effect can compress the Rayleigh-Taylor instability to a narrow wave number region. Even with a sufficient gyroviscosity and large enough flow velocity, the synergistic effect can completely suppressed the Rayleigh-Taylor instability in whole wave number region.

  3. Influence of tip clearance on pressure fluctuations in an axial flow pump

    Feng, Jianjun; Luo, Xingqi; Guo, Pengcheng; Wu, Guangkuan [Xi' an University, Xi' an (China)


    Rotor-stator interaction in axial pumps can produce pressure fluctuations and further vibrations even damage to the pump system in some extreme case. In this paper, the influence of tip clearance on pressure fluctuations in an axial flow water pump has been investigated by numerical method. Three-dimensional unsteady flow in the axial flow water pump has been simulated with different tip clearances between the impeller blade tip and the casing wall. In addition to monitoring pressure fluctuations at some typical points, a new method based on pressure statistics was proposed to determine pressure fluctuations at all grid nodes inside the whole pump. The comparison shows that the existence of impeller tip clearance magnifies the pressure fluctuations in the impeller region, from the hub to shroud. However, the effect on pressure fluctuation in the diffuser region is not evident. Furthermore, the tip clearance vortex has also been examined under different tip clearances.

  4. A study of casing treatment stall margin improvement phenomena. [for axial compressor rotor blade tips

    Prince, D. C., Jr.; Wisler, D. C.; Hilvers, D. E.


    The results of a program of experimental and analytical research in casing treatments over axial compressor rotor blade tips are presented. Circumferential groove, axial-skewed slot and blade angle slot treatments were tested at low speeds. With the circumferential groove treatment the stalling flow was reduced 5.8% at negligible efficiency sacrifice. The axial-skewed slot treatment improved the stalling flow by 15.3%; 1.8 points in peak efficiency were sacrificed. The blade angle slot treatment improved the stalling flow by 15.0%; 1.4 points in peak efficiency were sacrificed. The favorable stalling flow situations correlated well with observations of higher-than-normal surface pressures on the rotor blade pressure surfaces in the tip region, and with increased maximum diffusions on the suction surfaces. Annulus wall pressure gradients, especially in the 50 to 75% chord region, are also increased and blade surface pressure loadings are shifted toward the trailing edge for treated configurations.

  5. Determination of recent horizontal crustal movements and deformations of African and Eurasian plates in western Mediterranean region using geodetic-GPS computations extended to 2006 (from 1997) related to NAFREF and AFREF frames.

    Azzouzi, R.


    Determination of recent horizontal crustal movements and deformations of African and Eurasian plates in western Mediterranean region using geodetic-GPS computations extended to 2006 (from 1997) related to NAFREF and AFREF frames. By: R. Azzouzi*, M. Ettarid*, El H. Semlali*, et A. Rimi+ * Filière de Formation en Topographie Institut Agronomique et Vétérinaire Hassan II B.P. 6202 Rabat-Instituts MAROC + Département de la Physique du Globe Université Mohammed V Rabat MAROC This study focus on the use of the geodetic spatial technique GPS for geodynamic purposes generally in the Western Mediterranean area and particularly in Morocco. It aims to exploit this technique first to determine the geodetic coordinates on some western Mediterranean sites. And also this technique is used to detect and to determine movements cross the boundary line between the two African and Eurasian crustal plates on some well chosen GPS-Geodynamics sites. It will allow us also to estimate crustal dynamic parameters of tension that results. These parameters are linked to deformations of terrestrial crust in the region. They are also associated with tectonic constraints of the study area. The usefulness of repeated measurements of these elements, the estimate of displacements and the determination of their temporal rates is indisputable. Indeed, sismo-tectonique studies allow a good knowledge of the of earthquake processes, their frequency their amplitude and even of their prediction in the world in general and in Moroccan area especially. They allow also contributing to guarantee more security for all most important management projects, as projects of building great works (dams, bridges, nuclear centrals). And also as preliminary study, for the most important joint-project between Europe and Africa through the Strait of Gibraltar. For our application, 23 GPS monitoring stations under the ITRF2000 reference frame are chosen in Eurasian and African plates. The sites are located around the

  6. Excitation modes in non-axial nuclei

    Leviatan, A.; Ginnochio, J.N.


    Excitation modes of non-axial quadrupole shapes are investigated in the framework of interacting boson models. Both {gamma}-unstable and {gamma}-rigid nuclear shapes are considered for systems with one type of boson as well as with proton-neutron bosons. 6 refs.

  7. Cystic lesions accompanying extra-axial tumours

    Lohle, PNM; Wurzer, HAL; Seelen, PJ; Kingma, LM; Go, KG


    We examined the mechanism of cyst formation in extra-axial tumours in the central nervous system (CNS). Cyst fluid, cerebrospinal fluid (CSF) and blood plasma were analysed in eight patients with nine peritumoral cysts: four with meningiomas, two with intracranial and two spinal intradural schwannom

  8. Knowledge Based Design of Axial Flow Compressor

    Dinesh kumar.R


    Full Text Available In the aerospace industry with highly competitive market the time to design and delivery is shortening every day. Pressure on delivering robust product with cost economy is in demand in each development. Even though technology is older, it is new for each customer requirement and highly non-liner to fit one in another place. Gas turbine is considered one of a complex design in the aircraft system. It involves experts to be grouped with designers of various segments to arrive the best output. The time is crucial to achieve a best design and it needs knowledge automation incorporated with CAD/CAE tools. In the present work an innovative idea in the form of Knowledge Based Engineering for axial compressor is proposed, this includes the fundamental design of axial compressor integrated with artificial intelligence in the form of knowledge capturing and programmed with high level language (Visual Basis.Net and embedded into CATIA v5. This KBE frame work eases out the design and modeling of axial compressor design and produces 3D modeling for further flow simulation with fluid dynamic in Ansys-Fluent. Most of the aerospace components are developed through simulation driven product development and in this case it is established for axial compressor.

  9. Active axial stress in mouse aorta.

    Agianniotis, A; Rachev, A; Stergiopulos, N


    The study verifies the development of active axial stress in the wall of mouse aorta over a range of physiological loads when the smooth muscle cells are stimulated to contract. The results obtained show that the active axial stress is virtually independent of the magnitude of pressure, but depends predominately on the longitudinal stretch ratio. The dependence is non-monotonic and is similar to the active stress-stretch dependence in the circumferential direction reported in the literature. The expression for the active axial stress fitted to the experimental data shows that the maximum active stress is developed at longitudinal stretch ratio 1.81, and 1.56 is the longitudinal stretch ratio below which the stimulation does not generate active stress. The study shows that the magnitude of active axial stress is smaller than the active circumferential stress. There is need for more experimental investigations on the active response of different types of arteries from different species and pathological conditions. The results of these studies can promote building of refined constrictive models in vascular rheology. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Investigations on Experimental Impellers for Axial Blowers

    Encke, W.


    A selection of measurements obtained on experimental impellers for axial blowers will be reported. In addition to characteristic curves plotted for low and for high peripheral velocities, proportions and blade sections for six different blower models and remarks on the design of blowers will be presented.

  11. Wave propagation in axially moving periodic strings

    Sorokin, Vladislav S.; Thomsen, Jon Juel


    The paper deals with analytically studying transverse waves propagation in an axially moving string with periodically modulated cross section. The structure effectively models various relevant technological systems, e.g. belts, thread lines, band saws, etc., and, in particular, roller chain drive...

  12. The Analysis of Fluid Pressure Impact on String Force and Deformation in Oil and Gas Wells

    Gao Baokui


    Full Text Available Fluid pressure is a crucial factor to tubular string strength and deformation in oil and gas wells, and it is the most difficult factor to deal with. When the string constrained by downhole tools, such as packers, action pattern of fluid on string is changed. Calculation methods of string stress and deformation given by engineering handbooks doesn’t distinguish these issues in detail. So mistakes are often made when these methods are used. Tangled concepts lead to large calculation error. In this paper, the influence of fluid pressure on string axial force and deformation, buoyancy treatment in packed condition, are discussed roundly both in vertical wells and directional wells. Practical calculating method of string axial force through the hook load is presented, and element buoyancy in different borehole trajectory is given. It is found that the traditional simplified buoyancy coefficient method, which is used to calculate string axial force and axial extension, can only be used in vertical wells with tubular string suspended freely, because in this condition buoyancy acts on the bottom of string. If the string is constrained by downhole tools, such as packer or anchor, buoyancy could not be treated as usual. In directional well the buoyancy not only changes string axial force but induces shear stress in string cross section. When calculating the influence of fluid on string, operation sequence and constraints from borehole and downhole tools should be considered comprehensively.

  13. Narrowing of hysteresis of cubic-tetragonal martensitic transformation by weak axial stressing of ferromagnetic shape memory alloy

    Kosogor, Anna


    An influence of axial mechanical stress on the hysteresis of martensitic transformation and ordinary magnetostriction of ferromagnetic shape memory alloy has been described in the framework of a Landau-type theory of phase transitions. It has been shown that weak stress can noticeably reduce the hysteresis of martensitic transformation. Moreover, the anhysteretic deformation can be observed when the applied mechanical stress exceeds a critical stress value. The main theoretical results were compared with recent experimental data. It is argued that shape memory alloys with extremely low values of shear elastic modulus are the candidates for the experimental observation of large anhysteretic deformations.

  14. Distribution of wire deformation within strands of wire ropes

    MA Jun; GE Shi-rong; ZHANG De-kun


    Using ANSYS software, we developed a modeling program for several kinds of wire ropes with metal cores and built a geometric model for the 6x19 IWS wire rope. Through proper grid partitioning, a finite element model for calculating the deformation of wire rope was obtained. Completely constraining one end of the wire rope and applying an axial force to the other end, we established the boundary conditions for solving the model. In addition, we numerically simulated the stress and deformation of the wire, obtaining the deformation distribution of each wire within the wire rope under different laying directions.At the end, a tensile test of the 6x19 IWS wire rope was carried out and the results of simulation and experiment compared.

  15. Zirconolite, zircon and monazite-(Ce) U-Th-Pb age constraints on the emplacement, deformation and alteration history of the Cummins Range Carbonatite Complex, Halls Creek Orogen, Kimberley region, Western Australia

    Downes, Peter J.; Dunkley, Daniel J.; Fletcher, Ian R.; McNaughton, Neal J.; Rasmussen, Birger; Jaques, A. Lynton; Verrall, Michael; Sweetapple, Marcus T.


    In situ SHRIMP U-Pb dating of zirconolite in clinopyroxenite from the Cummins Range Carbonatite Complex, situated in the southern Halls Creek Orogen, Kimberley region, Western Australia, has provided a reliable 207Pb/206Pb age of emplacement of 1009 ± 16 Ma. Variably metamict and recrystallised zircons from co-magmatic carbonatites, including a megacryst ~1.5 cm long, gave a range of ages from ~1043-998 Ma, reflecting partial isotopic resetting during post-emplacement deformation and alteration. Monazite-(Ce) in a strongly foliated dolomite carbonatite produced U-Th-Pb dates ranging from ~900-590 Ma. Although the monazite-(Ce) data cannot give any definitive ages, they clearly reflect a long history of hydrothermal alteration/recrystallisation, over at least 300 million years. This is consistent with the apparent resetting of the Rb-Sr and K-Ar isotopic systems by a post-emplacement thermal event at ~900 Ma during the intracratonic Yampi Orogeny. The emplacement of the Cummins Range Carbonatite Complex probably resulted from the reactivation of a deep crustal structure within the Halls Creek Orogen during the amalgamation of Proterozoic Australia with Rodinia over the period ~1000-950 Ma. This may have allowed an alkaline carbonated silicate magma that was parental to the Cummins Range carbonatites, and generated by redox and/or decompression partial melting of the asthenospheric mantle, to ascend from the base of the continental lithosphere along the lithospheric discontinuity constituted by the southern edge of the Halls Creek Orogen. There is no evidence of a link between the emplacement of the Cummins Range Carbonatite Complex and mafic large igneous province magmatism indicative of mantle plume activity. Rather, patterns of Proterozoic alkaline magmatism in the Kimberley Craton may have been controlled by changing plate motions during the Nuna-Rodinia supercontinent cycles (~1200-800 Ma).

  16. Evolution of the axial system in craniates: morphology and function of the perivertebral musculature

    Schilling Nadja


    Full Text Available Abstract The axial musculoskeletal system represents the plesiomorphic locomotor engine of the vertebrate body, playing a central role in locomotion. In craniates, the evolution of the postcranial skeleton is characterized by two major transformations. First, the axial skeleton became increasingly functionally and morphologically regionalized. Second, the axial-based locomotion plesiomorphic for craniates became progressively appendage-based with the evolution of extremities in tetrapods. These changes, together with the transition to land, caused increased complexity in the planes in which axial movements occur and moments act on the body and were accompanied by profound changes in axial muscle function. To increase our understanding of the evolutionary transformations of the structure and function of the perivertebral musculature, this review integrates recent anatomical and physiological data (e.g., muscle fiber types, activation patterns with gross-anatomical and kinematic findings for pivotal craniate taxa. This information is mapped onto a phylogenetic hypothesis to infer the putative character set of the last common ancestor of the respective taxa and to conjecture patterns of locomotor and muscular evolution. The increasing anatomical and functional complexity in the muscular arrangement during craniate evolution is associated with changes in fiber angulation and fiber-type distribution, i.e., increasing obliqueness in fiber orientation and segregation of fatigue-resistant fibers in deeper muscle regions. The loss of superficial fatigue-resistant fibers may be related to the profound gross anatomical reorganization of the axial musculature during the tetrapod evolution. The plesiomorphic function of the axial musculature -mobilization- is retained in all craniates. Along with the evolution of limbs and the subsequent transition to land, axial muscles additionally function to globally stabilize the trunk against inertial and extrinsic

  17. Mandibular reconstruction using an axially vascularized tissue-engineered construct

    Khalil Mohamed R


    Full Text Available Abstract Background Current reconstructive techniques for continuity defects of the mandible include the use of free flaps, bone grafts, and alloplastic materials. New methods of regenerative medicine designed to restore tissues depend mainly on the so-called extrinsic neovascularization, where the neovascular bed originates from the periphery of the construct. This method is not applicable for large defects in irradiated fields. Methods We are introducing a new animal model for mandibular reconstruction using intrinsic axial vascularization by the Arterio-Venous (AV loop. In order to test this model, we made cadaveric, mechanical loading, and surgical pilot studies on adult male goats. The cadaveric study aimed at defining the best vascular axis to be used in creating the AV loop in the mandibular region. Mechanical loading studies (3 points bending test were done to ensure that the mechanical properties of the mandible were significantly affected by the designed defect, and to put a base line for further mechanical testing after bone regeneration. A pilot surgical study was done to ensure smooth operative and post operative procedures. Results The best vascular axis to reconstruct defects in the posterior half of the mandible is the facial artery (average length 32.5 ± 1.9 mm, caliber 2.5 mm, and facial vein (average length 33.3 ± 1.8 mm, caliber 2.6 mm. Defects in the anterior half require an additional venous graft. The defect was shown to be significantly affecting the mechanical properties of the mandible (P value 0.0204. The animal was able to feed on soft diet from the 3rd postoperative day and returned to normal diet within a week. The mandible did not break during the period of follow up (2 months. Conclusions Our model introduces the concept of axial vascularization of mandibular constructs. This model can be used to assess bone regeneration for large bony defects in irradiated fields. This is the first study to introduce the

  18. Permanent deformation testing for a new South African mechanistic pavement design method

    Anochie-Boateng, Joseph


    Full Text Available is to develop test protocols for hot-mix asphalt materials. To date, no permanent deformation test is incorporated into South African pavement design guides. The objective of this paper is to present the development process of a repeated load axial permanent...

  19. Extremely deformable structures


    Recently, a new research stimulus has derived from the observation that soft structures, such as biological systems, but also rubber and gel, may work in a post critical regime, where elastic elements are subject to extreme deformations, though still exhibiting excellent mechanical performances. This is the realm of ‘extreme mechanics’, to which this book is addressed. The possibility of exploiting highly deformable structures opens new and unexpected technological possibilities. In particular, the challenge is the design of deformable and bi-stable mechanisms which can reach superior mechanical performances and can have a strong impact on several high-tech applications, including stretchable electronics, nanotube serpentines, deployable structures for aerospace engineering, cable deployment in the ocean, but also sensors and flexible actuators and vibration absorbers. Readers are introduced to a variety of interrelated topics involving the mechanics of extremely deformable structures, with emphasis on ...

  20. Mechanisms of crustal deformation in the western US

    Turcotte, Donald L.


    The deformation processes in the western United States were studied, considering both deterministic models and random or statistical models. The role of the intracrustal delamination and mechanisms of crustal thinning were also examined. The application of fractal techniques to understand how the crust is deforming was studied in complex regions. Work continued on the development of a fractal based model for deformation in the western United States. Fractal studies were also extended to the study of topography and the geoid.

  1. The deformation and fracture of thick thermal barrier coatings

    Gao, Husheng

    Plasma-sprayed thick thermal barrier coatings (TTBCs) are being developed for thermal protection of diesel engine components in high temperature service. Comparing to thin thermal barrier coatings used in gas turbine industry, increased thickness causes some TTBCs failure to occur within the bulk of the coating materials and away from the interface. This necessitated the study of mechanical properties of the coating materials independent of the substrate. In order to enhance the performance and to predict the life of TTBCs, we have to understand the materials response under multiaxial stress states, the deformation mechanisms, failure criteria, and the constitutive relations. In this study, the deformation behavior, the deformation mechanisms, and the failure criteria were investigated. The results shows that under combined axial and shear loading, thin walled tubular specimens of ceramic coatings failed in one of two modes, a tensile failure perpendicular to the maximum principal stress when s1≥sTf or a shear failure through the thickness when s3≤sCf . Two apparatuses for in situ SEM torsion and compression testing were developed for deformation mechanisms investigation. The deformation mechanisms were identified as tensile microcracking, crack closing, and crack sliding. A model has been developed for the constitution relation of functionally graded TTBCs. It is shown that with a few simple experiments, this model can be used to predict the cyclic deformation behavior of the functionally graded TTBCs.

  2. Deformations of singularities

    Stevens, Jan


    These notes deal with deformation theory of complex analytic singularities and related objects. The first part treats general theory. The central notion is that of versal deformation in several variants. The theory is developed both in an abstract way and in a concrete way suitable for computations. The second part deals with more specific problems, specially on curves and surfaces. Smoothings of singularities are the main concern. Examples are spread throughout the text.

  3. Diffeomorphic Statistical Deformation Models

    Hansen, Michael Sass; Hansen, Mads/Fogtman; Larsen, Rasmus


    In this paper we present a new method for constructing diffeomorphic statistical deformation models in arbitrary dimensional images with a nonlinear generative model and a linear parameter space. Our deformation model is a modified version of the diffeomorphic model introduced by Cootes et al. Th...... with ground truth in form of manual expert annotations, and compared to Cootes's model. We anticipate applications in unconstrained diffeomorphic synthesis of images, e.g. for tracking, segmentation, registration or classification purposes....

  4. Microstructures and Crystallographic Misorientation in Experimentally Deformed Natural Quartz Single Crystals

    Thust, Anja; Heilbronner, Renée.; Stünitz, Holger


    Samples of natural milky quartz were deformed in a Griggs deformation apparatus at different confining pressures (700 MPa, 1000 MPa, 1500 MPa), with constant displacement rates of 1 * 10-6s-1, axial strains of 3 - 19%, and at a temperature of 900° C. The single crystal starting material contains a large number of H2O-rich fluid inclusions. Directly adjacent to the fluid inclusions the crystal is essentially dry (50-150H/106Si, determined by FTIR). The samples were cored from a narrow zone of constant 'milkyness' (i.e. same density of fluid inclusions) in a large single crystal in two different orientations (1) normal to one of the prism planes (⊥{m} orientation) and (2) 45° to and to (O+ orientation).During attaining of the experimental P and T conditions, numerous fluid inclusions decrepitate by cracking. Rapid crack healing produces regions of very small fluid inclusions ('wet' quartz domains). Only these regions are subsequently deformed by dislocation glide, dry quartz domains without cracking and decrepitation of fluid inclusions remain undeformed. Sample strain is not sufficient to cause recrystallization, so that deformation is restricted to dislocation glide. In experiments at lower temperatures (800, 700° C) or at lower strain rate (10-5s-1) there is abundant cracking and semi-brittle deformation, indicating that 900° C, (10-6s-1) represents the lower temperature end of crystal plastic deformation in these single crystals. Peak strengths (at 900° C) range between 150 and 250 MPa for most samples of both orientations. There is a trend of decreasing strength with increasing confining pressure, as described by Kronenberg and Tullis (1984) for quartzites, but the large variation in strength due to inhomogeneous sample strain precludes a definite analysis of the strength/pressure dependence in our single crystals. In the deformed samples, we can distinguish a number of microstructures and inferred different slip systems. In both orientations, deformation

  5. Grain-scale deformation in granular materials: time-lapse XCT-imaging of a deforming reservoir sandstone

    Hangx, Suzanne; Cordonnier, Benoît; Pijnenburg, Ronald; Renard, François; Spiers, Christopher


    Relating macroscopic deformation of granular media to grain-scale processes, such as grain fracturing, has been a focus of many studies. Understanding these processes is key for predicting surface subsidence and induced seismicity caused by hydrocarbon depletion, the hydraulic fracturing response of geothermal reservoirs, and post-seismic crustal deformation. With the development of state-of-the-art techniques, such as time-lapse X-ray tomography imaging during triaxial deformation, new avenues to investigate the operating mechanisms have opened up. As a first step to understanding grain-scale deformation processes, we performed a deformation experiment on highly porous sandstone, obtained from a depleting gas reservoir, using a novel small-scale triaxial deformation apparatus coupled to high-resolution 4D X-ray tomography, available at the European Synchrotron Radiation Facility (ESRF, Grenoble) and Université Grenoble Alpes. This state-of-the-art apparatus allows for 3D time-lapse imaging of samples, while deforming at pressure, temperature and fluid flow conditions relevant for geological reservoirs. We performed our experiment at relevant in-situ reservoir conditions (T = 100˚ C, 10 MPa pore pressure, 40 MPa effective confining pressure). Axial stress was increased step-wise until failure occurred, while continuously imaging deformation. This enables us to monitor progressive grain failure, and strain localisation, during deformation in real-time. Though the vast amount of data obtained from even a single test poses challenges for data analysis, this presentation will address the first results obtained from this experiment.

  6. Numerical study on the influence mechanism of inlet distortion on the stall margin in a transonic axial rotor

    Du, Juan; Lin, Feng; Chen, Jingyi; Morris, Scott C.; Nie, Chaoqun


    A numerical study is conducted to investigate the influence of inlet flow condition on tip leakage flow (TLF) and stall margin in a transonic axial rotor. A commercial software package FLUENT, is used in the simulation. The rotor investigated in this paper is ND_TAC rotor, which is the rotor of one-stage transonic compressor in the University of Notre Dame. Three varied inlet flow conditions are simulated. The inlet boundary condition with hub distortion provides higher axial velocity for the incoming flow near tip region than that for the clean inflow, while the incoming main flow possesses lower axial velocity near the tip region at tip distortion inlet boundary condition. Among the total pressure ratio curves for the three inlet flow conditions, it is found that the hub distorted inlet boundary condition improves the stall margin, while the tip distorted inlet boundary condition deteriorates compressor stability. The axial location of interface between tip leakage flow (TLF) and incoming main flow (MF) in the tip gap and the axial momentum ratio of TLF to MF are further examined. It is demonstrated that the axial momentum balance is the mechanism for interface movement. The hub distorted inflow could decrease the axial momentum ratio, suppress the movement of the interface between TLF and MF towards blade leading edge plane and thus enhance compressor stability.

  7. A Constitutive Model for Uni-axial Compaction of Non-adhesive Corn Stalk Powder

    Zhao Dong; Sun Yanling


    In order to study mechanical behaviors of corn stalk powder during the compaction, the yield criterion for corn stalk powder is proposed with a plasticity theory. From the stress-strain curves of uni-axial compaction test for corn stalk powder, the constitutive model, in which the equations are modified by experiments on corn stalk powder, is adopted to describe plastic behaviors of powder, and is discussed based on the incremental theory and deformation theory. The numerical results agree well with the experimental ones.

  8. Surface nanoscale axial photonics: Robust fabrication of high quality factor microresonators

    Sumetsky, M; Dulashko, Y; Fini, J M; Liu, X; Monberg, E M; Taunay, T F


    Recently introduced Surface Nanoscale Axial Photonics (SNAP) makes it possible to fabricate high Q-factor microresonators and other photonic microdevices by dramatically small deformation of the optical fiber surface. To become a practical and robust technology, the SNAP platform requires methods enabling reproducible modification of the optical fiber radius at nanoscale. In this Letter, we demonstrate super-accurate fabrication of high Q-factor microresonators by nanoscale modification of the optical fiber radius and refractive index using the CO2 laser and the UV excimer laser beam exposures. The achieved fabrication accuracy is better than 2 angstroms in variation of the effective fiber radius.

  9. Nonlinear Constitutive Equation for Green Sand Considering the Tri-axial Compression Behavior

    曾攀; 孔劲


    The compression characteristics of green sand were investigated experimentally, including the squeezing and yielding during deformation. An expression was developed for the transient compression modulus of sand during compression. Based on the hypothesis put forward of the compression state, the differential equation for the nonlinear constitutive equation was deduced by introducing a move-yield potential function. The state constitutive equation under the tri-axial experiment is further studied according to the sand attributes, considering the differential form of Hooke's law and the Mohr-Coulomb condition. The related experiment data are applied to verify the proposed constitutive model of sand.

  10. Might axial myofascial properties and biomechanical mechanisms be relevant to ankylosing spondylitis and axial spondyloarthritis?

    Masi, Alfonse T.


    Ankylosing spondylitis and axial spondyloarthropathy have characteristic age- and sex-specific onset patterns, typical entheseal lesions, and marked heritability, but the integrative mechanisms causing the pathophysiological and structural alterations remain largely undefined. Myofascial tissues are integrated in the body into webs and networks which permit transmission of passive and active tensional forces that provide stabilizing support and help to control movements. Axial myofascial hype...

  11. Might axial myofascial properties and biomechanical mechanisms be relevant to ankylosing spondylitis and axial spondyloarthritis?

    Masi, Alfonse T.


    Ankylosing spondylitis and axial spondyloarthropathy have characteristic age- and sex-specific onset patterns, typical entheseal lesions, and marked heritability, but the integrative mechanisms causing the pathophysiological and structural alterations remain largely undefined. Myofascial tissues are integrated in the body into webs and networks which permit transmission of passive and active tensional forces that provide stabilizing support and help to control movements. Axial myofascial hype...

  12. Role of deformation on giant resonances within the QRPA approach and the Gogny force

    Peru, S


    Fully consistent axially-symmetric-deformed Quasi-particle Random Phase Approximation (QRPA) calculations have been performed, in which the same Gogny D1S effective force has been used for both the Hartree-Fock-Bogolyubov mean field and the QRPA approaches. Giant resonances calculated in deformed $^{26-28}$Si and $^{22-24}$Mg nuclei as well as in the spherical $^{30}$Si and $^{28}$Mg isotopes are presented. Theoretical results for isovector-dipole and isoscalar monopole, quadrupole, and octupole responses are presented and the impact of the intrinsic nuclear deformation is discussed.

  13. Exotic octupole deformation in proton-rich Z=N nuclei

    Takami, Satoshi; Yabana, K. [Niigata Univ. (Japan); Matsuo, M.


    We study static non-axial octupole deformations in proton-rich Z=N nuclei, {sup 64}Ge, {sup 68}Se, {sup 72}Kr, {sup 76}Sr, {sup 80}Zr and {sup 84}Mo, by using the Skyrme Hartree-Fock plus BCS method with no restrictions on the nuclear shape. The calculation predicts that the oblate ground state in {sup 68}Se is extremely soft for the Y{sub 33} triangular deformation, and that in {sup 80}Zr the low-lying local minimum state coexisting with the prolate ground state has the Y{sub 32} tetrahedral deformation. (author)

  14. Electron states in quantum rings with structural distortions under axial or in-plane magnetic fields

    Planelles, J [Departament de Quimica Fisica i Analitica, Universitat Jaume I, Box 224, E-12080 Castello (Spain); Rajadell, F [Departament de Quimica Fisica i Analitica, Universitat Jaume I, Box 224, E-12080 Castello (Spain); Climente, J I [Departament de Quimica Fisica i Analitica, Universitat Jaume I, Box 224, E-12080 Castello (Spain)


    A comprehensive study of anisotropic quantum rings, QRs, subject to axial and in-plane magnetic field, both aligned and transverse to the anisotropy direction, is carried out. Elliptical QRs for a wide range of eccentricity values and also perfectly circular QRs including one or more barriers disturbing the QR current are considered. These models mimic anisotropic geometry deformations and mass diffusion occurring in the QR fabrication process. Symmetry considerations and simplified analytical models supply physical insight into the obtained numerical results. Our study demonstrates that, except for unusual extremely large eccentricities, QR geometry deformations only appreciably influence a few low-lying states, while the effect of barriers disturbing the QR current is stronger and affects all studied states to a similar extent. We also show that the response of the electron states to in-plane magnetic fields provides accurate information on the structural anisotropy.

  15. Detailing of deformation processes in polymeric crystals

    Slutsker, A. I.; Vettegren', V. I.; Kulik, V. B.; Hilarov, V. L.; Polikarpov, Yu. I.; Karov, D. D.


    Structural changes in polymer crystals (polyethylene, polyimide, and others) have been studied using the X-ray diffraction and Raman spectroscopy methods under different influences: tensile loading along the chain molecule axis and heating from 90 to 350 K. An increase in the molecule axial length under loading and a decrease in the molecule axial length upon heating have been identified and measured using X-ray diffraction. A decrease in the skeletal vibration frequency during loading and heating has been identified and measured using Raman spectroscopy, which indicates an increase in the molecule contour length in both cases. A technique for determining the change in the polyethylene molecule contour length in the crystal from the measured change in the skeletal vibration frequency has been justified. The contributions of two components, namely, skeletal (carbon-carbon) bond stretching and the change (an increase during stretching and a decrease during heating) in the angle between skeletal bonds, to the longitudinal deformation of polyethylene crystals, have been quantitatively estimated. It has been shown that the negative thermal expansion (contraction) of the polymer crystal is caused by the dominant contribution of the decrease in the bond angle.

  16. Structure and properties of copper after large strain deformation

    Rodak, Kinga; Molak, Rafal M.; Pakiela, Zbigniew


    Structure and properties of Cu in dependence on strain (from {epsilon}{proportional_to} 0.9 to {epsilon}{proportional_to} 15) during multi-axial compression processing at room temperature was investigated. The evolution of dislocation structure, misorientation distribution and crystallite size were observed by using transmission electron microscopy (TEM) and scanning electron microscopy (SEM) equipment with electron back scattered diffraction (EBSD) facility. The mechanical properties of yield strength (YS), ultimate tensile strength (UTS) and uniform elongation was performed on MTS QTest/10 machine equipped with digital image correlation method (DIC). The structure-flow stress relationship of multi-axial compression processing material at strains {epsilon}{proportional_to} 3.5 and {epsilon}{proportional_to} 5.5 is discussed. It is found that processing does not produce any drastic changes in deformation structure and the microstructural refinement is slow. These results indicate that dynamic recrystallization plays an important role during multi-axial compression process in this range of deformation (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  17. Deformation quantization of principal bundles

    Aschieri, Paolo


    We outline how Drinfeld twist deformation techniques can be applied to the deformation quantization of principal bundles into noncommutative principal bundles, and more in general to the deformation of Hopf-Galois extensions. First we twist deform the structure group in a quantum group, and this leads to a deformation of the fibers of the principal bundle. Next we twist deform a subgroup of the group of authomorphisms of the principal bundle, and this leads to a noncommutative base space. Considering both deformations we obtain noncommutative principal bundles with noncommutative fiber and base space as well.

  18. Piping inspection carriage having axially displaceable sensor

    Zollinger, William T.; Treanor, Richard C.


    A pipe inspection instrument carriage for use with a pipe crawler for performing internal inspections of piping surfaces. The carriage has a front leg assembly, a rear leg assembly and a central support connecting the two assemblies and for mounting an instrument arm having inspection instruments. The instrument arm has a y-arm mounted distally thereon for axially aligning the inspection instrumentation and a mounting block, a linear actuator and axial movement arm for extending the inspection instruments radially outward to operably position the inspection instruments on the piping interior. Also, the carriage has a rotation motor and gear assembly for rotating the central support and the front leg assembly with respect to the rear leg assembly so that the inspection instruments azimuthally scan the piping interior. The instrument carriage allows performance of all piping inspection operations with a minimum of moving parts, thus decreasing the likelihood of performance failure.

  19. Direct optical nanoscopy with axially localized detection

    Bourg, N; Dupuis, G; Barroca, T; Bon, P; Lécart, S; Fort, E; Lévêque-Fort, S


    Evanescent light excitation is widely used in super-resolution fluorescence microscopy to confine light and reduce background noise. Herein we propose a method of exploiting evanescent light in the context of emission. When a fluorophore is located in close proximity to a medium with a higher refractive index, its near-field component is converted into light that propagates beyond the critical angle. This so-called Supercritical Angle Fluorescence (SAF) can be captured using a hig-NA objective and used to determine the axial position of the fluorophore with nanometer precision. We introduce a new technique for 3D nanoscopy that combines direct STochastic Optical Reconstruction Microscopy (dSTORM) imaging with dedicated detection of SAF emission. We demonstrate that our approach of a Direct Optical Nanoscopy with Axially Localized Detection (DONALD) yields a typical isotropic 3D localization precision of 20 nm.

  20. Axial flow positive displacement worm compressor

    Murrow, Kurt David (Inventor); Giffin, Rollin George (Inventor); Fakunle, Oladapo (Inventor)


    An axial flow positive displacement compressor has an inlet axially spaced apart and upstream from an outlet. Inner and outer bodies have offset inner and outer axes extend from the inlet to the outlet through first and second sections of a compressor assembly in serial downstream flow relationship. At least one of the bodies is rotatable about its axis. The inner and outer bodies have intermeshed inner and outer helical blades wound about the inner and outer axes respectively. The inner and outer helical blades extend radially outwardly and inwardly respectively. The helical blades have first and second twist slopes in the first and second sections respectively. The first twist slopes are less than the second twist slopes. An engine including the compressor has in downstream serial flow relationship from the compressor a combustor and a high pressure turbine drivingly connected to the compressor by a high pressure shaft.

  1. Matrix calculus for axially symmetric polarized beam.

    Matsuo, Shigeki


    The Jones calculus is a well known method for analyzing the polarization of a fully polarized beam. It deals with a beam having spatially homogeneous polarization. In recent years, axially symmetric polarized beams, where the polarization is not homogeneous in its cross section, have attracted great interest. In the present article, we show the formula for the rotation of beams and optical elements on the angularly variant term-added Jones calculus, which is required for analyzing axially symmetric beams. In addition, we introduce an extension of the Jones calculus: use of the polar coordinate basis. With this calculus, the representation of some angularly variant beams and optical elements are simplified and become intuitive. We show definitions, examples, and conversion formulas between different notations.

  2. Consistent formulation of the spacelike axial gauge

    Burnel, A.; Van der Rest-Jaspers, M.


    The usual formulation of the spacelike axial gauge is afflicted with the difficulty that the metric is indefinite while no ghost is involved. We solve this difficulty by introducing a ghost whose elimination is such that the metric becomes positive for physical states. The technique consists in the replacement of the gauge condition nxA = 0 by the weaker one partial/sub 0/nxAroughly-equal0.

  3. Transonic Axial Splittered Rotor Tandem Stator Stage


    compressor rotor was designed incorporating a splitter vane between the principal blades . Historical experiments conducted by Dr. Arthur J...conventional rotor design . The stage is composed of the rotor and stator. The flow of the air passing through the rotor is turned, and the flow is required...derived results achieved the best blade geometry for design continuation. The best circumferential and axial placement for the splitter blade was

  4. Multimode interaction in axially excited cylindrical shells


    Cylindrical shells exhibit a dense frequency spectrum, especially near the lowest frequency range. In addition, due to the circumferential symmetry, frequencies occur in pairs. So, in the vicinity of the lowest natural frequencies, several equal or nearly equal frequencies may occur, leading to a complex dynamic behavior. So, the aim of the present work is to investigate the dynamic behavior and stability of cylindrical shells under axial forcing with multiple equal or nearly equal natural fr...

  5. Axial flux permanent magnet brushless machines

    Gieras, Jacek F; Kamper, Maarten J


    Axial Flux Permanent Magnet (AFPM) brushless machines are modern electrical machines with a lot of advantages over their conventional counterparts. They are being increasingly used in consumer electronics, public life, instrumentation and automation system, clinical engineering, industrial electromechanical drives, automobile manufacturing industry, electric and hybrid electric vehicles, marine vessels and toys. They are also used in more electric aircrafts and many other applications on larger scale. New applications have also emerged in distributed generation systems (wind turbine generators

  6. Enhancement of Optical Coherence Tomography Axial Resolution by Spectral Shaping

    孙汕; 郭继华; 高湔松; 薛平


    We propose a new method of changing the spectrum shape to improve the axial resolution of optical coherencetomography (OCT). Theoretical analysis shows that certain spectral shaping can shorten the coherence length.Comparisons of the simulation and experimental measurements of spectral shape and axial resolution of OCTare given, showing that the axial resolution of OCT is enhanced by a factor of 1.4.


    Daugherty, W.


    The fiberboard assembly within a 9975 shipping package contains a modest amount of moisture, which can migrate to the cooler regions of the package when an internal heat load is present. Typically, this leads to increased moisture levels in the bottom fiberboard layers, along with elevated chloride levels which can leach from the fiberboard. Concerns have been raised that this condition could lead to corrosion of the stainless steel drum. It has been postulated that checking the axial gap at the top of the package against the current 1 inch maximum criterion provides a sufficient indication regarding the integrity of the fiberboard and drum. This report estimates the increase in axial gap that might be expected for a given moisture increase in the bottom fiberboard layers, and the likelihood that the increase will create a nonconforming condition that will lead to identification of the moisture increase. Using data relating the fiberboard moisture content with the degree of compaction under load, the present analysis indicates that the axial gap will increase by 0.282 inch as the bottom fiberboard layers approach the saturation point. This increase will cause approximately 58% of packages with otherwise nominal package component dimensions to fail the axial gap criterion, based on a survey of axial gap values recorded in K-Area surveillance activities. As the moisture content increases above saturation, the predicted increase in axial gap jumps to 0.405 inch, which would result in 92% or more of all packages failing the axial gap criterion. The data and analysis described in this report are specific to cane fiberboard. While it is expected that softwood fiberboard will behave similarly, such behavior has not yet been demonstrated.

  8. Direct optical nanoscopy with axially localized detection

    Bourg, N.; Mayet, C.; Dupuis, G.; Barroca, T.; Bon, P.; Lécart, S.; Fort, E.; Lévêque-Fort, S.


    Evanescent light excitation is widely used in super-resolution fluorescence microscopy to confine light and reduce background noise. Here, we propose a method of exploiting evanescent light in the context of emission. When a fluorophore is located in close proximity to a medium with a higher refractive index, its near-field component is converted into light that propagates beyond the critical angle. This so-called supercritical-angle fluorescence can be captured using a high-numerical-aperture objective and used to determine the axial position of the fluorophore with nanometre precision. We introduce a new technique for three-dimensional nanoscopy that combines direct stochastic optical reconstruction microscopy (dSTORM) with dedicated detection of supercritical-angle fluorescence emission. We demonstrate that our approach of direct optical nanoscopy with axially localized detection (DONALD) typically yields an isotropic three-dimensional localization precision of 20 nm within an axial range of ∼150 nm above the coverslip.

  9. Axial gravity, massless fermions and trace anomalies

    Bonora, L.; Cvitan, M.; Prester, P. Dominis; Pereira, A. Duarte; Giaccari, S.; Štemberga, T.


    This article deals with two main topics. One is odd parity trace anomalies in Weyl fermion theories in a 4d curved background, the second is the introduction of axial gravity. The motivation for reconsidering the former is to clarify the theoretical background underlying the approach and complete the calculation of the anomaly. The reference is in particular to the difference between Weyl and massless Majorana fermions and to the possible contributions from tadpole and seagull terms in the Feynman diagram approach. A first, basic, result of this paper is that a more thorough treatment, taking account of such additional terms and using dimensional regularization, confirms the earlier result. The introduction of an axial symmetric tensor besides the usual gravitational metric is instrumental to a different derivation of the same result using Dirac fermions, which are coupled not only to the usual metric but also to the additional axial tensor. The action of Majorana and Weyl fermions can be obtained in two different limits of such a general configuration. The results obtained in this way confirm the previously obtained ones.

  10. Bessel beam CARS of axially structured samples

    Heuke, Sandro; Zheng, Juanjuan; Akimov, Denis; Heintzmann, Rainer; Schmitt, Michael; Popp, Jürgen


    We report about a Bessel beam CARS approach for axial profiling of multi-layer structures. This study presents an experimental implementation for the generation of CARS by Bessel beam excitation using only passive optical elements. Furthermore, an analytical expression is provided describing the generated anti-Stokes field by a homogeneous sample. Based on the concept of coherent transfer functions, the underling resolving power of axially structured geometries is investigated. It is found that through the non-linearity of the CARS process in combination with the folded illumination geometry continuous phase-matching is achieved starting from homogeneous samples up to spatial sample frequencies at twice of the pumping electric field wave. The experimental and analytical findings are modeled by the implementation of the Debye Integral and scalar Green function approach. Finally, the goal of reconstructing an axially layered sample is demonstrated on the basis of the numerically simulated modulus and phase of the anti-Stokes far-field radiation pattern. PMID:26046671

  11. Golimumab for the treatment of axial spondyloarthritis.

    Gelfer, Gita; Perry, Lisa; Deodhar, Atul


    Axial spondyloarthritis (axSpA) is a chronic, immune-mediated inflammatory disease of the axial skeleton that includes ankylosing spondylitis (AS) and non-radiographic axial spondyloarthritis (nr-axSpA). Patients with AS experience chronic pain due to sacroiliac joint and spinal inflammation, and may develop spinal ankylosing with syndesmophyte formation. Tumor necrosis factor α inhibitors (TNFi) have shown promise in the management of AS and axSpA by targeting the underlying inflammatory process, and providing symptomatic relief. Whether they alter the progression of the disease is uncertain. Golimumab is a fully human IgG1 monoclonal antibody that targets and downregulates the pro-inflammatory cytokine TNF-α. The use of golimumab has been shown to reduce the signs and symptoms of axSpA as well as improve patient function and quality reported outcomes. This review focuses on the biological rationale and the results of clinical trials with golimumab for the treatment of axSpA.

  12. GFFD: Generalized free-form deformation with scalar fields

    秦绪佳; 华炜; 方向; 鲍虎军; 彭群生


    The novel free-form deformation(FFD) technique presented in the paper uses scalar fields defined by skeletons with arbitrary topology. The technique embeds objects into the scalar field by assigning a field value to each point of the objects. When the space of the skeleton is changed, the distribution of the scalar field changes accordingly, which implicitly defines a deformation of the space. The generality of skeletons assures that the technique can freely define deformable regions to produce a broader range of shape deformations.

  13. Deformation of wrinkled membrane inflatable structures under concentrated loads

    WANG Chang-guo; DU Xing-wen; WAN Zhi-min; HE Xiao-dong


    The axisymmetric deformation of a paraboloidal membrane inflatable structure subjected to a concentrated load at its apex and a uniform intemal pressure was analyzed.The wrinkle angle was obtained according to the membrane theory when wrinkles appeared and determined the wrinkle region.The wrinkled deformation was obtained based on the relaxed energy function.The effects of inflation pressure and concentrated loads on the wrinkle ansle were analyzed and the deformation Was obtained at the apex of structure.According to the numerical analysis,the shape of deformed meridians with wrinkles Was obtained.

  14. Contemporary Crustal Motion and Deformation of South America Plate

    JIN Shuanggen; ZHU Wenyao


    This paper presents the contemporary motion and active deformation of South America plate and relative motion of Nazca-South America plate using space geodetic data. The South America plate is moving at average 14.5 mm/a with an azimuth of 15.2° and shrinking in the west-east at 10. 9 mm/a. The geodetic deformations of sites with respect to the South America plate are in quite good agreement with the estimated deformations from NNR-NUVEL1A, but the deformation of the western South America regions is very large.

  15. Dilatometric Investigation on Isothermal Transformation after Hot Deformation

    CHEN Ying; CHEN Qi-an


    The DAFT (deformation assistant ferrite transformation) of austenite and reverse DIFT (deformation induced ferrite transformation) during isothermal holding after deformation were investigated by means of hot deformation simulator with laser dilatometer. It is found that the reverse DIFT can occur in a wide temperature region, from the temperature above Ae3 to below A r3. However, during the isothermal holding, the reverse DIFT and DAFT of austenite take place, and therefore, the volume variation during holding time may be the combined effect of both phase transformations mentioned above. Nevertheless, the total volume and then the phase volume fraction change slowly, especially at lower holding temperature.

  16. Normative segment-specific axial and coronal angulation corridors of subaxial cervical column in axial rotation.

    Yoganandan, Narayan; Stemper, Brian D; Pintar, Frank A; Baisden, Jamie L; Shender, Barry S; Paskoff, Glenn


    In contrast to clinical studies wherein loading magnitudes are indeterminate, experiments permit controlled and quantifiable moment applications, record kinematics in multiple planes, and allow derivation of moment-angulation corridors. Axial and coronal moment-angulation corridors were determined at every level of the subaxial cervical spine, expressed as logarithmic functions, and level-specificity of range of motion and neutral zones were evaluated. segmental primary axial and coupled coronal motions do not vary by level. Although it is known that cervical spine responses are coupled, segment-specific corridors of axial and coronal kinematics under axial twisting moments from healthy normal spines are not reported. Ten human cadaver columns (23-44 years, mean: 34 +/- 6.8) were fixed at the ends and targets were inserted to each vertebra to obtain kinematics in axial and coronal planes. The columns were subjected to pure axial twisting moments. Range of motion and neutral zone for primary-axial and coupled-coronal rotation components were determined at each spinal level. Data were analyzed using factorial analysis of variance. Moment-rotation angulations were expressed using logarithmic functions, and mean +/-1 standard deviation corridors were derived at each level for both components. Moment-angulations responses were nonlinear. Each segmental curve for both components was well represented by a logarithmic function (r2 > 0.95). Factorial analysis of variance indicated that the biomechanical metrics are spinal level-specific (P specific responses. The presentation of moment-angulation corridors for both metrics forms a dataset for the normal population. These segment-specific nonlinear corridors may help clinicians assess dysfunction or instability. These data will assist mathematical models of the spine in improved validation and lead to efficacious design of stabilizing systems.

  17. Orbital magnetism in axially deformed sodium clusters From scissors mode to dia-para magnetic anisotropy

    Nesterenko, V O; Reinhard, P G; Iudice, N L; De Souza-Cruz, F F; Marinelli, J R


    Low-energy orbital magnetic dipole excitations, known as scissors mode (SM), are studied in alkali metal clusters. Subsequent dynamic and static effects are explored. The treatment is based on a self-consistent microscopic approach using the jellium approximation for the ionic background and the Kohn-Sham mean field for the electrons. The microscopic origin of SM and its main features (structure of the mode in light and medium clusters, separation into low- and high-energy plasmons, coupling high-energy M1 scissors and E2 quadrupole plasmons, contributions of shape isomers, etc) are discussed. The scissors M1 strength acquires large values with increasing cluster size. The mode is responsible for the van Vleck paramagnetism of spin-saturated clusters. Quantum shell effects induce a fragile interplay between Langevin diamagnetism and van Vleck paramagnetism and lead to a remarkable dia-para anisotropy in magnetic susceptibility of particular light clusters. Finally, several routes for observing the SM experime...

  18. The role of elasticity in normal faulting and the development of axial topography in the oceanic lithosphere

    Olive, J. L.; Behn, M. D.; Mittelstaedt, E. L.; Ito, G.


    In this study we compare 2D numerical simulations of lithospheric extension with and without elasticity in order to investigate its role on the development of normal faults and axial topography at oceanic spreading centers. Specifically, we use a finite difference / marker-in-cell technique to model visco-elasto-plastic (VEP) and visco-plastic (VP) deformation of the lithosphere under extension. Simulated fault zones form spontaneously as the system evolves and the associated strain localization is achieved by reducing the cohesion in proportion to the accumulated plastic strain in regions undergoing yielding. We investigate the development of different fault modes (e.g. growth of multiple faults vs. a single large-offset fault) both in a VP and a VEP lithosphere for a range of lithospheric thicknesses, spreading rates, and rates of cohesion loss. In our simulations, fault-induced bending of a VP lithosphere occurs on a larger wavelength and with less overall vertical deflection than in a VEP lithosphere. Flexural rotation of long-lived, initially steep faults does not require elasticity, but appears to have a strain-rate-dependent wavelength in a VP lithosphere. We find that thinner lithosphere and rapid weakening promote the growth of large-offset faults in both a VEP and a VP lithosphere. The effect of neglecting elasticity appears greater in thicker lithosphere, where a VP rheology favors the growth of multiple steep faults instead of a few large-offset faults. We also note that a VP lithosphere requires more total extension to achieve the same faulting pattern as a VEP lithosphere. This may be due to distributed viscous deformation taking up a portion of the extension in the VP case. To further quantify our numerical results, we develop scaling relations describing the build-up of topographic and bending stresses in a faulted VP lithosphere and compare them to those previously derived for a VEP lithosphere. These relations are then implemented in a force


    SHA Feng-huan; ZHAO Long-mao; YANG Gui-tong


    The dynamic response of a double-walled carbon nanotube embedded in elastic medium subjected to periodic disturbing forces is investigated. Investigation of the dynamic buckling of a double-walled carbon nanotube develops continuum model. The effect of the van der Waals forces between two tubes and the surrounding elastic medium for axial dynamic buckling are considered. The buckling model subjected to periodic disturbing forces and the critical axial strain and the critical frequencies are given. It is found that the critical axial strain of the embedded multi-walled carbon nanotube due to the intertube van der Waals forces is lower than that of an embedded single-walled carbon nanotube. The van der Waals forces and the surrounding elastic medium affect region of dynamic instability. The van der Waals forces increase the critical frequencies of a double-walled carbon nanotube. The effect of the surrounding elastic medium for the critical frequencies is small.

  20. Axial Hall effect and universality of holographic Weyl semi-metals

    Copetti, Christian; Landsteiner, Karl


    The holographic Weyl semimetal is a model of a strongly coupled topological semi-metal. A topological quantum phase transition separates a topological phase with non-vanishing anomalous Hall conductivity from a trivial state. We investigate how this phase transition depends on the parameters of the scalar potential (mass and quartic self coupling) finding that the quantum phase transition persists for a large region in parameter space. We then compute the axial Hall conductivity. The algebraic structure of the axial anomaly predicts it to be 1/3 of the electric Hall conductivity. We find that this holds once a non-trivial renormalization effect on the external axial gauge fields is taken into account. Finally we show that the phase transition also occurs in a top-down model based on a consistent truncation of type IIB supergravity.

  1. Deformable Simplicial Complexes

    Misztal, Marek Krzysztof

    In this dissertation we present a novel method for deformable interface tracking in 2D and 3D|deformable simplicial complexes (DSC). Deformable interfaces are used in several applications, such as fluid simulation, image analysis, reconstruction or structural optimization. In the DSC method......, the interface (curve in 2D; surface in 3D) is represented explicitly as a piecewise linear curve or surface. However, the domain is also subject to discretization: triangulation in 2D; tetrahedralization in 3D. This way, the interface can be alternatively represented as a set of edges/triangles separating...... demonstrate those strengths in several applications. In particular, a novel, DSC-based fluid dynamics solver has been developed during the PhD project. A special feature of this solver is that due to the fact that DSC maintains an explicit interface representation, surface tension is more easily dealt with...

  2. Autogenous Deformation of Concrete

    Autogenous deformation of concrete can be defined as the free deformation of sealed concrete at a constant temperature. A number of observed problems with early age cracking of high-performance concretes can be attributed to this phenomenon. During the last 10 years , this has led to an increased...... focus on autogenous deformation both within concrete practice and concrete research. Since 1996 the interest has been significant enough to hold international, yearly conferences entirely devoted to this subject. The papers in this publication were presented at two consecutive half-day sessions...... at the American Concrete Institute’s Fall Convention in Phoenix, Arizona, October 29, 2002. All papers have been reviewed according to ACI rules. This publication, as well as the sessions, was sponsored by ACI committee 236, Material Science of Concrete. The 12 presentations from 8 different countries indicate...

  3. Autogenous Deformation of Concrete

    Autogenous deformation of concrete can be defined as the free deformation of sealed concrete at a constant temperature. A number of observed problems with early age cracking of high-performance concretes can be attributed to this phenomenon. During the last 10 years , this has led to an increased...... focus on autogenous deformation both within concrete practice and concrete research. Since 1996 the interest has been significant enough to hold international, yearly conferences entirely devoted to this subject. The papers in this publication were presented at two consecutive half-day sessions...... at the American Concrete Institute’s Fall Convention in Phoenix, Arizona, October 29, 2002. All papers have been reviewed according to ACI rules. This publication, as well as the sessions, was sponsored by ACI committee 236, Material Science of Concrete. The 12 presentations from 8 different countries indicate...

  4. Post-laminectomy deformities

    Fabiano Stumpf Lutz


    Full Text Available Objective: To present the deformities and evaluate the results of their treatment. Methods: Retrospective study of patients with deformity following surgical access to the spinal canal. Fifteen patients who met the inclusion criteria were included. Patients without complete data in medical records were excluded. Results: Fourteen patients underwent surgical treatment and one patient received conservative treatment with vest type TLSO. The average angle of kyphosis correction was 87° preoperatively to 38° postoperatively, while the associated scoliosis correction was 69° preoperatively to 23° postoperatively. Conclusions: The prevention of deformity should be emphasized to avoid laminectomy alone, while laminoplasty should be the procedure of choice for canal access in surgeries where there is no need for resection of the posterior elements.

  5. Deformation of C isotopes

    Kanada-Enyo, Y


    Systematic analysis of the deformations of proton and neutron densities in even-even C isotopes was done based on the method of antisymmetrized molecular dynamics. The $E2$ transition strength was discussed in relation to the deformation. We analyze the $B(E2;2^+_1\\to 0^+_1)$ in $^{16}$C, which has been recently measured to be abnormally small. The results suggest the difference of the deformations between proton and neutron densities in the neutron-rich C isotopes. It was found that stable proton structure in C isotopes plays an important role in the enhancement the neutron skin structure as well as in the systematics of $B(E2)$ in the neutron-rich C.

  6. Axial T2* mapping in intervertebral discs: a new technique for assessment of intervertebral disc degeneration

    Hoppe, Sven; Quirbach, Sebastian; Krause, Fabian G.; Benneker, Lorin M. [Inselspital, Berne University Hospital, Department of Orthopaedic Surgery, Berne (Switzerland); Mamisch, Tallal C. [Inselspital, Berne University Hospital, Department of Radiology, Berne (Switzerland); Werlen, Stefan [Clinic Sonnenhof, Department of Radiology, Berne (Switzerland)


    To demonstrate the potential benefits of biochemical axial T2* mapping of intervertebral discs (IVDs) regarding the detection and grading of early stages of degenerative disc disease using 1.5-Tesla magnetic resonance imaging (MRI) in a clinical setting. Ninety-three patients suffering from lumbar spine problems were examined using standard MRI protocols including an axial T2* mapping protocol. All discs were classified morphologically and grouped as ''healthy'' or ''abnormal''. Differences between groups were analysed regarding to the specific T2* pattern at different regions of interest (ROIs). Healthy intervertebral discs revealed a distinct cross-sectional T2* value profile: T2* values were significantly lower in the annulus fibrosus compared with the nucleus pulposus (P = 0.01). In abnormal IVDs, T2* values were significantly lower, especially towards the centre of the disc representing the expected decreased water content of the nucleus (P = 0.01). In herniated discs, ROIs within the nucleus pulposus and ROIs covering the annulus fibrosus showed decreased T2* values. Axial T2* mapping is effective to detect early stages of degenerative disc disease. There is a potential benefit of axial T2* mapping as a diagnostic tool, allowing the quantitative assessment of intervertebral disc degeneration. circle Axial T2* mapping effective in detecting early degenerative disc disease. (orig.)

  7. LDA measurements on the turbulent flow characteristics of a small-sized axial fan

    Kim, Jang Kweon [Kunsan National Univ., Kunsan (Korea, Republic of)


    The operating point of a small-sized axial fan for refrigerator is strongly dependent upon the system resistance. Therefore, the turbulent flow characteristics around a small-sized axial fan may change significantly according to the operating point. This study represents three-dimensional turbulent flow characteristics around a small-sized axial fan measured at the four operating points such as {phi}=0.1, 0.18, 0.25 and 0.32 by using fiber-optic type LDA system. This LDA system is composed of a 5 W Argon-ion laser, two optics in back-scatter mode, three BSA's, a PC, and a three-dimensional automatic traversing system. A kind of paraffin fluid is utilized for supplying particles by means of fog generator. Mean velocity profiles downstream of a small--sized axial fan along the radial distance show that both the streamwise and the tangential components exist predominantly in downstream except {phi}=0.1 and have a maximum value at the radial distance ratio of about 0.8, but the radial component, which its velocity is relatively small, is acting role that only turns flow direction to the outside or the central part of axial fan. Moreover, all of the velocity components downstream at {phi}=0.1 show much smaller than those upstream due to the static pressure rise at the low-flowrate region.

  8. Might axial myofascial properties and biomechanical mechanisms be relevant to ankylosing spondylitis and axial spondyloarthritis?

    Masi, Alfonse T


    Ankylosing spondylitis and axial spondyloarthropathy have characteristic age- and sex-specific onset patterns, typical entheseal lesions, and marked heritability, but the integrative mechanisms causing the pathophysiological and structural alterations remain largely undefined. Myofascial tissues are integrated in the body into webs and networks which permit transmission of passive and active tensional forces that provide stabilizing support and help to control movements. Axial myofascial hypertonicity was hypothesized as a potential excessive polymorphic trait which could contribute to chronic biomechanical overloading and exaggerated stresses at entheseal sites. Such a mechanism may help to integrate many of the characteristic host, pathological, and structural features of ankylosing spondylitis and axial spondyloarthritis. Biomechanical stress and strain were recently documented to correlate with peripheral entheseal inflammation and new bone formation in a murine model of spondyloarthritis. Ankylosing spondylitis has traditionally been classified by the modified New York criteria, which require the presence of definite radiographic sacroiliac joint lesions. New classification criteria for axial spondyloarthritis now include patients who do not fulfill the modified New York criteria. The male-to-female sex ratios clearly differed between the two patient categories - 2:1 or 3:1 in ankylosing spondylitis and 1:1 in non-radiographic axial spondyloarthritis - and this suggests a spectral concept of disease and, among females, milder structural alterations. Magnetic resonance imaging of active and chronic lesions in ankylosing spondylitis and axial spondyloarthritis reveals complex patterns, usually interpreted as inflammatory reactions, but shows similarities to acute degenerative disc disease, which attributed to edema formation following mechanical stresses and micro-damage. A basic question is whether mechanically induced microinjury and immunologically mediated

  9. Reports on crustal movements and deformations

    Cohen, S. C.; Peck, T.


    Studies of tectonic plate motions, regional crustal deformations, strain accumulation and release, deformations associated with earthquakes and fault motion, and micro-plate motion, were collected and are summarized. To a limited extent, papers dealing with global models of current plate motions and crustal stress are included. The data base is restricted to articles appearing in reveiwed technical journals during the years 1970-1980. The major journals searched include: Journal of Geophysical Research (solid earth), Tectonophysics, Bulletin of the Seismological Society of America, Geological Society of America Bulletin, Geophysical Journal of the Royal Astronomical Society, and the Journal of Geology.

  10. Heat treatment deformations

    Bavaro, A. (Soliveri SpA, Caravaggio (Italy))


    Types and causes of heat treatement derived isotropic and anisotropic dilatancies in ferrous materials are reviewed. The concepts are developed in such a way as to allow extension to all materials exhibiting martensitic tempering behaviour. This paper intends to illustrate the basic processes of dimensional variations undergone by the materials under heat treatments. The parametric analysis includes an analysis of the interactions amongst the parameters themselves. The relative importance of each parameter is assessed in order to determine methods to attenuate deformation action. Simplified examples are offered to provide technicians explanations as to why specific deformations occur and indications on improved materials working techniques.

  11. Effects of Axial Non-uniform Tip Clearances on Aerodynamic Performance of a Transonic Axial Compressor

    Hongwei MA; Baihe LI


    This paper presents a numerical investigation of effects of axial non-uniform tip clearances on the aerodynamic performance of a transonic axial compressor rotor (NASA Rotor 37). The three-dimensional steady flow field within the rotor passage was simulated with the datum tip clearance of 0.356 mm at the design wheel speed of 17188.7 rpm. The simulation results are well consistent with the measurement results, which verified the numeri-cal method. Then the three-dimensional steady flow field within the rotor passage was simulated respectively with different axial non-uniform tip clearances. The calculation results showed that optimal axial non-uniform tip clearances could improve the compressor performance, while the efficiency and the pressure ratio of the com-pressor were increased. The flow mechanism is that the axial non-uniform tip clearance can weaken the tip leak-age vortex, blow down low-energy fluids in boundary layers and reduce both flow blockage and tip loss.

  12. Intrinsic carpal ligaments on MR and multidetector CT arthrography: comparison of axial and axial oblique planes

    Lee, Ryan K.L.; Griffith, James F.; Ng, Alex W.H.; Law, Eric K.C. [The Chinese University of Hong Kong, Department of Imaging and Interventional Radiology, Prince Of Wales Hospital, Hong Kong (China); Tse, W.L.; Wong, Clara W.Y.; Ho, P.C. [The Chinese University of Hong Kong, Department of Orthopedics and Traumatology, Prince Of Wales Hospital, Hong Kong (China)


    To compare axial and oblique axial planes on MR arthrography (MRA) and multidetector CT arthrography (CTA) to evaluate dorsal and volar parts of scapholunate (SLIL) and lunotriquetral interosseous (LTIL) ligaments. Nine cadaveric wrists of five male subjects were studied. The visibility of dorsal and volar parts of the SLIL and LTIL was graded semi-quantitatively (good, intermediate, poor) on MRA and CTA. The presence of a ligament tear was determined on arthrosocopy and sensitivity, specificity and accuracy of tear detection were calculated. Oblique axial imaging was particularly useful for delineating dorsal and volar parts of the LTIL on MRA with overall 'good' visibility increased from 11 % to 78 %. The accuracy of MRA and CTA in revealing SLIL and LTIL tear was higher using the oblique axial plane. The overall accuracy for detecting SLIL tear on CTA improved from 94 % to 100 % and from 89 % to 94 % on MRA; the overall accuracy of detecting LTIL tear on CTA improved from 89 % to 100 % and from 72 % to 89 % on MRA Oblique axial imaging during CT and MR arthrography improves detection of tears in the dorsal and volar parts of both SLIL and LTIL. (orig.)

  13. Swept source optical coherence tomography Gabor fusion splicing technique for microscopy of thick samples using a deformable mirror

    Costa, Christopher; Bradu, Adrian; Rogers, John; Phelan, Pauline; Podoleanu, Adrian


    We present a swept source optical coherence tomography (OCT) system at 1060 nm equipped with a wavefront sensor at 830 nm and a deformable mirror in a closed-loop adaptive optics (AO) system. Due to the AO correction, the confocal profile of the interface optics becomes narrower than the OCT axial range, restricting the part of the B-scan (cross section) with good contrast. By actuating on the deformable mirror, the depth of the focus is changed and the system is used to demonstrate Gabor filtering in order to produce B-scan OCT images with enhanced sensitivity throughout the axial range from a Drosophila larvae. The focus adjustment is achieved by manipulating the curvature of the deformable mirror between two user-defined limits. Particularities of controlling the focus for Gabor filtering using the deformable mirror are presented.

  14. Calculation of rotational deformity in pediatric supracondylar humerus fractures

    Henderson, Eric R.; Egol, Kenneth A.; Bosse, Harold J.P. van; Schweitzer, Mark E.; Pettrone, Sarah K. [NYU Hospital for Joint Diseases, New York, NY (United States); Feldman, David S. [NYU Hospital for Joint Diseases, New York, NY (United States); NYU Hospital for Joint Diseases, Pediatric Orthopaedic Surgery, Center for Children, New York, NY (United States)


    Supracondylar humerus fractures (SCHF) are common in the pediatric population. Cubitus varus deformity (CVD) is the most common long-term complication of SCHFs and may lead to elbow instability and deficits in throwing or extension. Distal fragment malrotation in the axial plane disposes to fragment tilt and CVD; however, no simple method of assessing fracture malrotation exists. This study tested a mathematical method of measuring axial plane malrotation in SCHFs based on plain radiographs. A pediatric SCHF model was made, and x-rays were taken at known intervals of rotation. Five independent, blinded observers measured these films. Calculated rotation for each data set was compared to the known rotation. The identical protocol was performed for an aluminum phantom. The reliability and agreement of the rotation values were good for both models. This method is a reliable, accurate, and cost-effective means of calculating SCHF distal fragment malrotation and warrants clinical application. (orig.)

  15. Superdeformed rotational bands in the presence of Y44 deformation

    Hamamoto, Ikuko; Mottelson, Ben


    The observation of ΔI = 4 staggering in the rotational spectra of superdeformed nuclei suggests the occurence of Y44 deformations in the nuclear shape with associated C4 v point-symmetry for the rotational Hamiltonian. We have investigated the general class of Hamiltonians with such symmetry. In addition, we require the axially symmetric terms to favour rotation about an axis that is perpendicular to the long axis of nuclear shape. The δI = 4 staggering can indeed result from the tunneling between the four equivalent minima that occur in the plane perpendicular to the superdeformation symmetry axis, but the occurence of this effect is a subtle matter depending sensitively on the axially symmetric terms in the Hamiltonian.

  16. Energy absorption of aluminum alloy thin-walled tubes under axial impact

    Sun, Hongtu; Wang, Jian [Ludong University, Yantai (China); Shen, Guozhe; Hu, Ping [Dalian University of Technology, Dalian (China)


    Aluminum alloys are important technological materials for achieving the lightweight design of automotive structures. Many works have reported on the deformation and energy absorption of thin-walled tubes. Multicorner tubes with extra concave corners in the cross section were presented in this study to improve the energy absorption efficiency of aluminum alloy thin-walled tubes. The axial crushing of square and multicorner thin-walled tubes was simulated with the same cross-sectional perimeter. The method of folding element was applied to predict the crushing behavior of the thin-walled tubes under axial impact. The corners on the cross section were discussed to determine their effect on the energy absorption performance of thin-walled tubes. Results showed that the increasing performance of energy absorption of aluminum alloy thin-walled tubes was caused by the increasing number of corners on the cross section of multicorner tubes. Both the number and size of corners had an important effect on the crushing force efficiency of multicorner tubes. The maximum crushing force efficiency of multicorner tubes was 11.6% higher than that of square tubes with the same material consumption of thin-walled tubes. The multicorner tubes with 12 corners showed better energy absorption performance than the tubes with more than 12 corners; this high number of corners could lead to the small size of corners or unstable deformations. The high energy absorption performance of multicorner tubes prefers increasing the corner number and corner size of adjacent sides at the same time.

  17. Shear wave splitting and subcontinental mantle deformation

    Silver, Paul G.; Chan, W. Winston


    We have made measurements of shear wave splitting in the phases SKS and SKKS at 21 broadband stations in North America, South America, Europe, Asia, and Africa. Measurements are made using a retrieval scheme that yields the azimuth of the fast polarization direction ϕ and delay time δt of the split shear wave plus uncertainties. Detectable anisotropy was found at most stations, suggesting that it is a general feature of the subcontinental mantle. Delay times range from 0.65 s to 1.70 s and average about 1 s. Somewhat surprisingly, the largest delay time is found in the 2.7 b.y.-old Western Superior Province of the Canadian Shield. The splitting observations are interpreted in terms of the strain-induced lattice preferred orientation of mantle minerals, especially olivine. We consider three hypotheses concerning the origin of the continental anisotropy: (1) strain associated with absolute plate motion, as in the oceanic upper mantle, (2) crustal stress, and (3) the past and present internal deformation of the subcontinental upper mantle by tectonic episodes. It is found that the last hypothesis is the most successful, namely that the most recent significant episode of internal deformation appears to be the best predictor of ϕ. For stable continental regions, this is interpreted as "fossil" anisotropy, whereas for presently active regions, such as Alaska, the anisotropy reflects present-day tectonic activity. In the stable portion of North America there is a good correlation between delay time and lithospheric thickness; this is consistent with the anisotropy being localized in the subcontinental lithosphere and suggests that intrinsic anisotropy is approximately constant. The acceptance of this hypothesis has several implications for subcontinental mantle deformation. First, it argues for coherent deformation of the continental lithosphere (crust and mantle) during orogenies. This implies that the anisotropic portion of the lithosphere was present since the

  18. Axial interbody arthrodesis of the L5-S1 segment: a systematic review of the literature.

    Schroeder, Gregory D; Kepler, Christopher K; Vaccaro, Alexander R


    The object of this study was to determine the fusion rate and safety profile of an axial interbody arthrodesis of the L5-S1 motion segment. A systematic search of MEDLINE was conducted for literature published between January 1, 2000, and August 17, 2014. All peer-reviewed articles related to the fusion rate of L5-S1 and the safety profile of an axial interbody arthrodesis were evaluated. Seventy-four articles were identified, but only 15 (13 case series and 2 retrospective cohort studies) met the study inclusion criteria. The overall pseudarthrosis rate at L5-S1 was 6.9%, and the rate of all other complications was 12.9%. A total of 14.4% of patients required additional surgery, and the infection rate was 5.4%. Deformity studies reported a significantly increased rate of complications (46.3%), and prospectively collected data demonstrated significantly higher complication (36.8%) and revision (22.6%) rates. Lastly, studies with a conflict of interest reported lower complication rates (12.4%). A systematic review of the literature indicates that an axial interbody fusion performed at the lumbosacral junction is associated with a high fusion rate (93.15%) and an acceptable complication rate (12.90%). However, these results are based mainly on retrospective case series by authors with a conflict of interest. The limited prospective data available indicate that the actual fusion rate may be lower and the complication rate may be higher than currently reported.

  19. Theoretical Analysis on Mechanical Behavior of Axially Loaded Recycled Aggregate Concrete Filled Steel Tubes

    Yijie Huang


    Full Text Available A new mechanical model for analysing the behaviour of axially loaded recycled aggregate concrete filled steel tubes (RACFSTs stub columns is presented in this study. The model is derived from the typical elastoplasticity, the nonlinear elastic mechanics, and the properties of materials. Based on the mechanical model, a novel numerical program is developed. The mechanical model and the numerical program are adopted to study the effect of recycled coarse aggregate (RCA replacement percentage on RACFST mechanical behaviour. The complete load-deformation relationship of specimens, the steel tube axial and circumferential stresses, and the performance of the confined core concrete and the variation of interaction are also investigated. The analytical results indicate that this model is able to capture the mechanical behaviour of RACFST. It is also found that the axial and circumferential stresses of steel tube change nonlinearly during the loading stages. It is concluded that the behaviour of the confined core concrete is significantly influenced by the confining pressure. The steel tube confinement could improve the mechanical behaviour of RAC effectively and the RCA replacement percentage slightly changes the response of core concrete. Finally, the relations between confined core concrete and confining pressure are analysed.

  20. Numerical study on air-structure coupling dynamic characteristics of the axial fan blade

    Chen, Q. G.; Xie, B.; Li, F.; Gu, W. G.


    In order to understand the dynamic characteristics of the axial-flow fan blade due to the effect of rotating stress and the action of unsteady aerodynamic forces caused by the airflow, a numerical simulation method for air-structure coupling in an axial-flow fan with fixed rear guide blades was performed. The dynamic characteristics of an axial-flow fan rotating blade were studied by using the two-way air-structure coupling method. Based on the standard k-ε turbulence model, and using weak coupling method, the preceding six orders modal parameters of the rotating blade were obtained, and the distributions of stress and strain on the rotating blade were presented. The results show that the modal frequency from the first to the sixth order is 3Hz higher than the modal frequency without considering air-structure coupling interaction; the maximum stress and the maximum strain are all occurred in the vicinity of root area of the blade no matter the air-structure coupling is considered or not, thus, the blade root is the dangerous location subjected to fatigue break; the position of maximum deformation is at the blade tip, so the vibration of the blade tip is significant. This study can provide theoretical references for the further study on the strength analysis and mechanical optimal design.

  1. Analysis of blade vibration response induced by rotating stall in axial compressor


    An experimental and numerical study was conducted to investigate the forced response of blade vibration induced by rotating stall in a low speed axial compressor.Measurements have been made of the transient stalling process in a low speed axial compressor stage.The CFD study was performed using solution of 3-dimensional Navier-Stokes equations,coupled with structure finite element models for the blades to identify modal shapes and structural deformations simultaneously.Interactions between fluid and structure were managed in a coupled manner,based on the interface information exchange until convergence in each time step.Based on the rotating stall measurement data obtained from a low speed axial compressor,the blade aeroelastic response induced by the rotating stall flow field was analyzed to study the vibration characteristics and the correlation between the phenomena.With this approach,good agreement between the numerical results and the experimental data was observed.The flow phenomena were well captured,and the results indicate that the rotating field stall plays a significant role in the blade vibration and stress affected by the flow excitation.

  2. Co-axial multicusp source for low axial energy spread ion beam production

    Lee, Y; Leung, K N; Vujic, J L; Williams, M D; Zahir, N


    A co-axial multicusp ion source has been designed and tested. This source uses a new magnetic filter configuration. This magnetic filter is efficient in modifying the plasma potential distribution which can reduce the axial energy spread of the extracted ion beam. Energy spreads as low as 0.6 eV have been obtained. The electron temperature in this source has also been found to be about 0.1 eV. Furthermore, the new source configuration is capable of adjusting the radial plasma potential distribution which can improve the transverse ion energy, which results in a low beam emittance. The co-axial source can be used for a number of different applications such as ion projection lithography and radioactive ion beam projects.

  3. Co-axial multicusp source for low axial energy spread ion beam production

    Lee, Y. E-mail:; Gough, R.A.; Leung, K.N.; Vujic, J.; Williams, M.D.; Zahir, N


    A co-axial multicusp ion source has been designed and tested. This source uses a new magnetic filter configuration. This magnetic filter is efficient in modifying the plasma potential distribution which can reduce the axial energy spread of the extracted ion beam. Energy spreads as low as 0.6 eV have been obtained. The electron temperature in this source has also been found to be about 0.1 eV. Furthermore, the new source configuration is capable of adjusting the radial plasma potential distribution which can improve the transverse ion energy, which results in a low beam emittance. The co-axial source can be used for a number of different applications such as ion projection lithography and radioactive ion beam projects.

  4. Co-axial multicusp source for low axial energy spread ion beam production

    Lee, Y.; Gough, R. A.; Leung, K. N.; Vujic, J.; Williams, M. D.; Zahir, N.


    A co-axial multicusp ion source has been designed and tested. This source uses a new magnetic filter configuration. This magnetic filter is efficient in modifying the plasma potential distribution which can reduce the axial energy spread of the extracted ion beam. Energy spreads as low as 0.6 eV have been obtained. The electron temperature in this source has also been found to be about 0.1 eV. Furthermore, the new source configuration is capable of adjusting the radial plasma potential distribution which can improve the transverse ion energy, which results in a low beam emittance. The co-axial source can be used for a number of different applications such as ion projection lithography and radioactive ion beam projets.

  5. Unsteady Tip Clearance Flow in an Isolated Axial Compressor Rotor

    Hongwu ZHANG; Xiangyang DENG; Jingyi CHEN; Weiguang HUANG


    The paper investigates effects of operating conditions, tip clearance sizes and external unsteady excitations on the unsteady tip clearance flow in an isolated axial compressor rotor by unsteady 3D Navier-Stokes simulations. The results show that the unsteady tip clearance vortex takes a periodic flow behavior in the rotor tip region. With the decrease of the flow coefficient, the unsteady tip clearance vortex is enhanced and its frequency becomes lower. A larger tip clearance size can cause bigger unsteady fluctuation amplitude and a lower fluctuation frequency of the tip clearance vortex at the near stall operating condition. The unsteady excitation with the natural frequency of the tip clearance vortex can enhance the unsteadiness of the tip clearance vortex and improve the overall rotor performance. The frequency of the unsteady tip clearance vortex is independent of external unsteady excitations with different frequencies.

  6. Performance studies on an axial flow compressor stage

    Sitaram, N.


    A low-speed, medium loaded axial flow compressor stage is studied experimentally and theoretically. The flow compressor facility, composed of an inlet guide vane row, a rotor blade row, and a stator blade row, and the principles of the streamline curvature method (SCM) and the Douglas-Neumann cascade program are described. The radial distribution of the flow properties, the rotor blade static pressure distribution, and the lift coefficient and relative flow angle derived experimentally and theoretically are compared. It is determined that there is good correlation between the experimental flow properties and the SCM data, the Douglas-Neumann cascade program and experimental rotor blade static pressure data, and the experimental and theoretical lift coefficients only in the midspan region. Modifications to the SCM and the Douglas-Neumann cascade program in order to improve their accuracy are discussed.

  7. Effect of inlet box on performance of axial flow fans

    Jingyin LI; Hua TIAN; Xiaofang YUAN


    Numerical investigations on 3D flow fields in an axial flow fan with and without an inlet box have been extensively conducted, focusing on the variation of fan performance caused by the internal flow fields and the velocity evenness at the exit of the inlet box. It is interest-ing to find that although the inlet box is well designed in accordance with basic design principles, there is a flow separation region in it. Furthermore, this flow separation and the resulting uneven velocity distribution at the exit lead to some decrease in the efficiency and an increase in the total pressure rise of the fan. This research shows that the inlet box needs further improvement and such a check on the flow fields is of value for the design of inlet boxes.

  8. An Efficient Virtual Trachea Deformation Model

    Cui Tong


    Full Text Available In this paper, we present a virtual tactile model with the physically based skeleton to simulate force and deformation between a rigid tool and the soft organ. When the virtual trachea is handled, a skeleton model suitable for interactive environments is established, which consists of ligament layers, cartilage rings and muscular bars. In this skeleton, the contact force goes through the ligament layer, and produces the load effects of the joints , which are connecting the ligament layer and cartilage rings. Due to the nonlinear shape deformation inside the local neighbourhood of a contact region, the RBF method is applied to modify the result of linear global shape deformation by adding the nonlinear effect inside. Users are able to handle the virtual trachea, and the results from the examples with the mechanical properties of the human trachea are given to demonstrate the effectiveness of the approach.

  9. Marginally Deformed Starobinsky Gravity

    Codello, A.; Joergensen, J.; Sannino, Francesco


    We show that quantum-induced marginal deformations of the Starobinsky gravitational action of the form $R^{2(1 -\\alpha)}$, with $R$ the Ricci scalar and $\\alpha$ a positive parameter, smaller than one half, can account for the recent experimental observations by BICEP2 of primordial tensor modes....

  10. Factors Influencing Quasistatic Modeling of Deformation and Failure in Rock-Like Solids by the Smoothed Particle Hydrodynamics Method

    X. W. Tang


    actual test of marble material. Typical results of the axial stress-strain response from infinitesimal to finite deformation as well as the progressive failure process for the marble tests are given and the influences of various factors are discussed. It is found that only provided proper choices of particle momentum equation and the smoothing length parameter, the SPH method is capable for favorably reproducing the deformation and progressive failure evolution in rock-like materials under quasistatic compression loads.


    WangShuangxu; ZhangXi; ZhangSixin; XueFuping


    By processing and analyzing geodetic data of vertical deformation, fault deformation and horizontal deformation by GPS in Gansu-Ningxia-Qinghai area and by comparing them with geological structures and many medium to strong earthquake activities in this area, some features of recent tectonic deformation anomaly and the development of medium to strong earthquakes are studied. The results show that: ①Near the main faults tectonic deformations are relatively large. The amount of vertical movement and the deformation status evolve with time. The horizontal movement and deformation show obvious compressional strike-slip character. ②Thedominant stress of tectonic deformation and seismic development in this area comes from the persistent northeastward compression of Qinghai-Tibet block;The time-spatial distribution evolution of tectonic deformation and seismic activities are closely related to dynamic evolution of block motion and regional tectonic stress field. ③The abnormal uplift and high-gradient deformation belts and remarkable fault deformation anormaly on the borders of regional tectonic blocks are indicators of developing moderate-to-strong earthquakes but earthquakes may not necessarily take place in the position of maxium deformation, it usually occurred in the region where fault deformation anormaly shows “trend accumulation-acceleration-turn ” variation character or nearby. On the basis of above study, a preliminary prediction for strong earthquake risk in this area is given.

  12. Axial Tomography from Digitized Real Time Radiography

    Zolnay, A. S.; McDonald, W. M.; Doupont, P. A.; McKinney, R. L.; Lee, M. M.


    Axial tomography from digitized real time radiographs provides a useful tool for industrial radiography and tomography. The components of this system are: x-ray source, image intensifier, video camera, video line extractor and digitizer, data storage and reconstruction computers. With this system it is possible to view a two dimensional x-ray image in real time at each angle of rotation and select the tomography plane of interest by choosing which video line to digitize. The digitization of a video line requires less than a second making data acquisition relatively short. Further improvements on this system are planned and initial results are reported.

  13. Ankylosing Spondylitis versus Nonradiographic Axial Spondyloarthritis

    Glintborg, Bente; Sørensen, Inge J; Østergaard, Mikkel


    OBJECTIVE: To compare baseline disease activity and treatment effectiveness in biologic-naive patients with nonradiographic axial spondyloarthritis (nr-axSpA) and ankylosing spondylitis (AS) who initiate tumor necrosis factor inhibitor (TNFi) treatment and to study the role of potential confounders....../disease duration/TNFi-type/smoking/baseline disease activity) on TNFi adherence and response [e.g., Bath Ankylosing Spondylitis Activity Index (BASDAI) 50%/20 mm]. RESULTS: The study included 1250 TNFi-naive patients with axSpA (29% nr-axSpA, 50% AS, 21% lacked radiographs of sacroiliac joints). Patients...

  14. Tunable axial potentials for atom chip waveguides

    Stickney, James A; Imhof, Eric; Kroese, Bethany R; Crow, Jonathon A R; Olson, Spencer E; Squires, Matthew B


    We present a method for generating algebraically precise magnetic potentials along the axis of a cold atom waveguide near the surface of an atom chip. With a single chip design consisting of several wire pairs, various axial potentials can be created, including double wells, triple wells, and pure harmonic traps with suppression of higher order terms. We characterize the error along a harmonic trap between the expected algebraic form and magnetic field simulations and find excel- lent agreement, particularly at small displacements from the trap center. Finally, we demonstrate experimental control over the bottom fields of an asymmetric double well potential.

  15. Composite Axial Flow Propulsor for Small Aircraft


    This work focuses on the design of an axial flow ducted fan driven by a reciprocating engine. The solution minimizes the turbulization of the flow around the aircraft. The fan has a rotor - stator configuration. Due to the need for low weight of the fan, a carbon/epoxy composite material was chosen for the blades and the driving shaft.The fan is designed for optimal isentropic efficiency and free vortex flow. A stress analysis of the rotor blade was performed using the Finite Element  Method....

  16. Cervical Spine Axial Rotation Goniometer Design

    Emin Ulaş Erdem


    Full Text Available To evaluate the cervical spine rotation movement is quiet harder than other joints. Configuration and arrangement of current goniometers and devices is not always practic in clinics and some methods are quiet expensive. The cervical axial rotation goniometer designed by the authors is consists of five pieces (head apparatus, chair, goniometric platform, eye pads and camera. With this goniometer design a detailed evaluation of cervical spine range of motion can be obtained. Besides, measurement of "joint position sense" which is recently has rising interest in researches can be made practically with this goniometer.

  17. Through-Flow Calculations in Axial Turbomachinery


    downstzega of the effective throat which is displaced upstream away from its kominal plano flow •_stion. Test data .-n nigh deflection blading tested in...AXIAL PIE ANGs-L;- VrELOC.I- T/Y SI~NG,’ c (,o nd) 2 .959 00 SO~ IS~N1RO iCoWLE tNJ\\\\ NJ\\v ON45l~5INi +U~SWC E.AAINZN5W~N3~6 8Lk5~ P-tO RM~ C -5A

  18. Single Band Helical Antenna in Axial Mode

    Parminder Singh


    Full Text Available Helical antennas have been widely used in a various useful applications, due to their low weight and low profile conformability, easy and cheap realization.Radiation properties of this antenna are examined both theoretically and experimentally. In this paper, an attempt has been made to investigate new helical antenna structure for Applications. CST MWS Software is used for the simulation and design calculations of the helical antennas. The axial ratio, return loss, VSWR, Directivity, gain, radiation pattern is evaluated. Using CST MWS simulation software proposed antenna is designed/simulated and optimized. The antenna exhibits a single band from 0 GHz to 3 GHz for GPS and several satellite applications

  19. Assembling Stabilization of the Rayleigh-Taylor Instability by the Effects of Finite Larmor Radius and Sheared Axial Flow

    Jian Guangde; Huang Lin; Qiu Xiaoming


    The assembling stabilizing effect of the finite Larmor radius (FLR) and the sheared axial flow (SAF) on the Rayleigh-Taylor instability in Z-pinch implosions is studied by means of the incompressible finite Larmor radius magnetohydrodynamic (MHD) equations. The finite Larmor radius effects are introduced in the momentum equation with the sheared axial flow through an anisotropic ion stress tensor. In this paper a linear mode equation is derived that is valid for arbitrary kL, where k is the wave number and L is the plasma shell thickness. Numerical solutions are presented. The results indicate that the short-wavelength modes of the RayleighTaylor instability are easily stabilized by the individual effect of the finite Larmor radius or the sheared axial flow. The assembling effects of the finite Larmor radius and sheared axial flow can heavily mitigate the Rayleigh-Taylor instability, and the unstable region can be compressed considerably.

  20. Deformed Algebras and Generalizations of Independence on Deformed Exponential Families

    Hiroshi Matsuzoe


    Full Text Available A deformed exponential family is a generalization of exponential families. Since the useful classes of power law tailed distributions are described by the deformed exponential families, they are important objects in the theory of complex systems. Though the deformed exponential families are defined by deformed exponential functions, these functions do not satisfy the law of exponents in general. The deformed algebras have been introduced based on the deformed exponential functions. In this paper, after summarizing such deformed algebraic structures, it is clarified how deformed algebras work on deformed exponential families. In fact, deformed algebras cause generalization of expectations. The three kinds of expectations for random variables are introduced in this paper, and it is discussed why these generalized expectations are natural from the viewpoint of information geometry. In addition, deformed algebras cause generalization of independences. Whereas it is difficult to check the well-definedness of deformed independence in general, the κ-independence is always well-defined on κ-exponential families. This is one of advantages of κ-exponential families in complex systems. Consequently, we can well generalize the maximum likelihood method for the κ-exponential family from the viewpoint of information geometry.

  1. Deformation of chlorite in naturally deformed low-grade rocks

    Bons, A.J.


    The intracrystalline deformation of chlorite in naturally deformed low-grade rocks was investigated with transmission electron microscopy (TEM). As in other phyllosilicates, the deformation of chlorite is dominated by the (001) slip plane. Slip along this plane is very easy through the generation an

  2. GB-SAR Experiment On Deformation Extraction And System Error Analysis

    Qu, Shibo; Wang, Yanping; Tan, Weixian; Hong, Wen


    Ground Based Synthetic Aperture Radar (GB-SAR) provides a new method to monitoring deformation in relative small region. In this paper, we present the GB-SAR imaging geometry and analyze the interferometric phase for the purpose of deformation monitoring. Deformation monitoring error sources are also analyzed through sensitivity equations, including frequency instability and its influence on interferometric phase and deformation extraction, incident angle and monitoring distance. At last, a deformation monitoring experiment is carry out using ASTRO (Advanced Scannable Two-dimensional Rail Observation system), a GB-SAR system constructed by Institute of Electronics Chinese Academy of Sciences (IECAS). The deformation monitoring results show good consistent with metal objects' movement.

  3. General solution of collector performance with axial conduction and end effects

    Shouman, A. R.; Tag, I. A.

    The Phillips solution of the flat-plate solar collector is extended and utilized to examine the influence of the end losses on collector performance. The results of this study show that the influence of the end temperatures of the absorber plate is more significant than the losses due to the axial conductivity of an insulated end collector plate. It will be shown that for an insulated end collector, the loss in the heat removal factor due to axial conductivity is negligible in the region of interest for flat-plate collectors. However, the end temperatures of the collector plate have more significant influence on the same factor, showing losses in some regions and improvements in other regions. This study emphasizes the necessity of measuring the temperature of the absorber plate at both the fluid inlet and exit locations in order to determine accurately the collector performance parameters.

  4. Postural deformities in Parkinson's disease

    Doherty, K.M.; Warrenburg, B.P.C. van de; Peralta, M.C.; Silveira-Moriyama, L.; Azulay, J.P.; Gershanik, O.S.; Bloem, B.R.


    Postural deformities are frequent and disabling complications of Parkinson's disease (PD) and atypical parkinsonism. These deformities include camptocormia, antecollis, Pisa syndrome, and scoliosis. Recognition of specific postural syndromes might have differential diagnostic value in patients prese

  5. Nonperturbative effects in deformation quantization

    Periwal, V


    The Cattaneo-Felder path integral form of the perturbative Kontsevich deformation quantization formula is used to explicitly demonstrate the existence of nonperturbative corrections to na\\"\\i ve deformation quantization.

  6. Control of Precambrian basement deformation zones on emplacement of the Laramide Boulder batholith and Butte mining district, Montana, United States

    Berger, Byron R.; Hildenbrand, Thomas G.; O'Neill, J. Michael


    What are the roles of deep Precambrian basement deformation zones in the localization of subsequent shallow-crustal deformation zones and magmas? The Paleoproterozoic Great Falls tectonic zone and its included Boulder batholith (Montana, United States) provide an opportunity to examine the importance of inherited deformation fabrics in batholith emplacement and the localization of magmatic-hydrothermal mineral deposits. Northeast-trending deformation fabrics predominate in the Great Falls tectonic zone, which formed during the suturing of Paleoproterozoic and Archean cratonic masses approximately 1,800 mega-annum (Ma). Subsequent Mesoproterozoic to Neoproterozoic deformation fabrics trend northwest. Following Paleozoic through Early Cretaceous sedimentation, a Late Cretaceous fold-and-thrust belt with associated strike-slip faulting developed across the region, wherein some Proterozoic faults localized thrust faulting, while others were reactivated as strike-slip faults. The 81- to 76-Ma Boulder batholith was emplaced along the reactivated central Paleoproterozoic suture in the Great Falls tectonic zone. Early-stage Boulder batholith plutons were emplaced concurrent with east-directed thrust faulting and localized primarily by northwest-trending strike-slip and related faults. The late-stage Butte Quartz Monzonite pluton was localized in a northeast-trending pull-apart structure that formed behind the active thrust front and is axially symmetric across the underlying northeast-striking Paleoproterozoic fault zone, interpreted as a crustal suture. The modeling of potential-field geophysical data indicates that pull-apart?stage magmas fed into the structure through two funnel-shaped zones beneath the batholith. Renewed magmatic activity in the southern feeder from 66 to 64 Ma led to the formation of two small porphyry-style copper-molybdenum deposits and ensuing world-class polymetallic copper- and silver-bearing veins in the Butte mining district. Vein orientations

  7. Nanoscale deformation mechanisms in bone.

    Gupta, Himadri S; Wagermaier, Wolfgang; Zickler, Gerald A; Raz-Ben Aroush, D; Funari, Sérgio S; Roschger, Paul; Wagner, H Daniel; Fratzl, Peter


    Deformation mechanisms in bone matrix at the nanoscale control its exceptional mechanical properties, but the detailed nature of these processes is as yet unknown. In situ tensile testing with synchrotron X-ray scattering allowed us to study directly and quantitatively the deformation mechanisms at the nanometer level. We find that bone deformation is not homogeneous but distributed between a tensile deformation of the fibrils and a shearing in the interfibrillar matrix between them.

  8. Structure of the Anayet Permian basin (Axial Zone, Central Pyrenees)

    Rodriguez, L.; Cuevas, J.; Tubía, J. M.


    The Anayet Permian basin was generated by strike-slip tectonics that opened subsident basins with pull-apart geometries in the western Spanish Axial Zone (between the Aragon and Tena valleys). A continental succession of Permian age, that represents the first post-variscan deposits in the area, fills the basin and covers discordantly Devonian to Carboniferous limestones, sandstones and slates. Permian deposits have been classically divided in four main detrital groups, with three basic volcanic episodes interbedded (Gisbert, 1984, Bixel, 1987): the Grey Unit (50-120 m, Estefanian to Kungurian) with slates, conglomerates, tobaceous slates, coal and pyroclastic deposits, the Transition Unit (50 m maximum) showing grey and red sandstones and lutites with oolitic limestones intercalated, the Lower Red Unit (250 m) composed of cross-bedded red sandstones and andesitic volcanic rocks at the top, and finally the Upper Red Unit (400 m minimum, top eroded) formed by three fining up megasequences of carbonates, red sandstones and lutites with lacustrine carbonates intercalated and alkali basalts at the top. Increasingly older rocks are found towards the western part of the basin, where its depocenter is located. South-vergent angular folds deform the Permian sedimentary succession. Fold axes are N115 °E-trending, almost horizontal and are characterized by a remarkably constant orientation. Folds exhibit a long limb dipping slightly to the north and a short vertical limb, occasionally reversed. In the Anayet basin four main folds, with a wavelength of 400 m, can be distinguished, two anticlines and two synclines, with minor folds associated. Related to the angular folds an axial plane foliation, E-trending and dipping 40 to 60° to the north, is developed in the lutites. The more competent rocks, conglomerates and breccias, only locally show a spaced fracture cleavage. No main thrusts have been detected in Permian rocks. However, minor scale decollements, usually low angle

  9. Single Rod Vibration in Axial Flow

    Weichselbaum, Noah; Wang, Shengfu; Bardet, Philippe


    Fluid structure interaction of a single rod in axial flow is a coupled dynamical system present in many application including nuclear reactors, steam generators, and towed antenna arrays. Fluid-structure response can be quantified thanks to detailed experimental data where both structure and fluid responses are recorded. Such datum deepen understanding of the physics inherent to the system and provide high-dimensionality quantitative measurements to validate coupled structural and CFD codes with various level of complexity. In this work, single rods fixed on both ends in a concentric pipe, are subjected to an axial flow with Reynolds number based on hydraulic diameter of Re =4000. Rods of varying material stiffness and diameter are utilized in the experiment resulting in a range of dimensionless U between 0.5 and 1, where U = (ρA/EI)1/2uL. Experimental measurements of the velocity field around the rod are taken with PIV from time-resolved Nd:YLF laser and a high speed CMOS camera. Three-dimensional and temporal vibration and deflection of the rod is recorded with shadowgraphy utilizing two sets of pulsed high power LED and dedicated CMOS camera. Through integration of these two diagnostics, it is possible to reconstruct the full FSI domain providing unique validation data.

  10. Multi-frequency axial transmission bone ultrasonometer.

    Tatarinov, Alexey; Egorov, Vladimir; Sarvazyan, Noune; Sarvazyan, Armen


    The last decade has seen a surge in the development of axial transmission QUS (Quantitative UltraSound) technologies for the assessment of long bones using various modes of acoustic waves. The condition of cortical bones and the development of osteoporosis are determined by numerous mechanical, micro-structural, and geometrical or macro-structural bone properties like hardness, porosity and cortical thickness. Such complex manifestations of osteoporosis require the evaluation of multiple parameters with different sensitivities to the various properties of bone that are affected by the disease. This objective may be achieved by using a multi-frequency ultrasonic examination The ratio of the acoustic wavelength to the cortical thickness can be changed by varying the frequency of the ultrasonic pulse propagating through the long bone that results in the change in composition of the induced wave comprised of a set of numerous modes of guided, longitudinal, and surface acoustic waves. The multi-frequency axial transmission QUS method developed at Artann Laboratories (Trenton, NJ) is implemented in the Bone Ultrasonic Scanner (BUSS). In the current version of the BUSS, a train of ultrasonic pulses with 60, 100, 400, 800, and 1200 kHz frequencies is used. The developed technology was tested on a variety of bone phantoms simulating normal, osteopenic, and osteoporotic bones. The results of this study confirm the feasibility of the multi-frequency approach for the assessment of the processes leading to osteoporosis.

  11. Indication of Negative Triaxial Deformation in the Very Neutron-Deficient Odd-A Re Isotopes

    周小红; 许甫荣; 郑勇; 张玉虎


    For the 9/2-[514] bands in light odd-A Re isotopes, the energy signature splitting and its relation with the signature dependence of M1 transition matrix elements are investigated in connection with the deviation of nuclear shape from axial symmetry. By comparing the energy signature splittings and relative magnetic transition rates between the experimental values and the theoretical calculations assuming axially symmetric shapes, it is found that discrepancies increase with the decreasing neutron number. These discrepancies strongly suggest an appreciable negative γ deformation for the very neutron-deficient odd-A Re isotopes.


    赵斐; 何晓雁; 乔建新


    36 autoclaved fly ash brick masonries are built for axial compressive tests.An experiment is carried out with the strength of both masonry and mortar serving as the basic parameters and the dial indicator used for measuring the deformation of masonries.Based on the experiment, the development features of cracks and the deformation patterns of masonries under compressure are analyzed.In light of the results of axial compressive tests of all the 36 masonries, a calculative formula of the compressive strength of autoclaved fly ash brick is established, which will supply experimental data for compiling regional technical codes.And, thus, the application of autoclaved fly ash brick will be extended.%试验以块体和砂浆强度为基本参数,砌筑36个蒸压粉煤灰砖砌体试件进行轴心受压试验,并配合百分表量测砌体变形.通过蒸压粉煤灰砖砌体轴心受压试验,分析了砌体受压时裂缝的发展特点和变形规律,根据36个试件的抗压试验结果,建立了蒸压粉煤灰砖砌体抗压强度的计算公式,为相关规范的编制提供试验数据,以利于蒸压粉煤灰砖的推广应用.

  13. Production of low axial energy spread ion beams with multicusp sources

    Lee, Yung -Hee Y. [Univ. of California, Berkeley, CA (United States)


    Multicusp ion sources are capable of producing ions with low axial energy spread which are necessary in applications such as: ion projection lithography (IPL) and focused ion beams for the next generation lithographic tools and nuclear science experiments such as radioactive ion beam production. The axial ion energy spread for multicusp source is approximately 6 eV which is too large for IPL and radioactive ion beam applications. The addition of a magnetic filter which consists of a pair of permanent magnets to the multicusp source reduces the energy spread considerably. The reduction is due to the improvement in the uniformity of the axial plasma potential distribution in the discharge region. Axial ion energy spread of the filament driven ion source has been measured using three different techniques. In all cases, it was found to be less than 2 eV. Energy spread of the radio frequency (RF) driven source has also been explored, and it was found to be less than 3 eV with the proper RF-shielding. A new multicusp source configuration has been designed and constructed to further reduce the energy spread. To achieve a more uniform axial plasma potential distribution, a cylindrical magnetic filter has been designed and constructed for a 2-cm-diameter source. This new source configuration, the co-axial source, is new in its kind. The energy spread in this source has been measured to be a record low of 0.6 eV. Because of the novelty of this device, some plasma parameters inside the source have been studied. Langmuir probe has been used to measure the plasma potential, the electron temperature and the density distribution.

  14. Leaf hydraulic conductance for a tank bromeliad: axial and radial pathways for moving and conserving water.

    North, Gretchen B; Lynch, Frank H; Maharaj, Franklin D R; Phillips, Carly A; Woodside, Walter T


    Epiphytic plants in the Bromeliaceae known as tank bromeliads essentially lack stems and absorptive roots and instead take up water from reservoirs formed by their overlapping leaf bases. For such plants, leaf hydraulic conductance is plant hydraulic conductance. Their simple strap-shaped leaves and parallel venation make them suitable for modeling leaf hydraulic conductance based on vasculature and other anatomical and morphological traits. Plants of the tank bromeliad Guzmania lingulata were investigated in a lowland tropical forest in Costa Rica and a shaded glasshouse in Los Angeles, CA, USA. Stomatal conductance to water vapor and leaf anatomical variables related to hydraulic conductance were measured for both groups. Tracheid diameters and numbers of vascular bundles (veins) were used with the Hagen-Poiseuille equation to calculate axial hydraulic conductance. Measurements of leaf hydraulic conductance using the evaporative flux method were also made for glasshouse plants. Values for axial conductance and leaf hydraulic conductance were used in a model based on leaky cable theory to estimate the conductance of the radial pathway from the vein to the leaf surface and to assess the relative contributions of both axial and radial pathways. In keeping with low stomatal conductance, low stomatal density, low vein density, and narrow tracheid diameters, leaf hydraulic conductance for G. lingulata was quite low in comparison with most other angiosperms. Using the predicted axial conductance in the leaky cable model, the radial resistance across the leaf mesophyll was predicted to predominate; lower, more realistic values of axial conductance resulted in predicted radial resistances that were closer to axial resistance in their impact on total leaf resistance. Tracer dyes suggested that water uptake through the tank region of the leaf was not limiting. Both dye movement and the leaky cable model indicated that the leaf blade of G. lingulata was structurally and

  15. Cosmetic and Functional Nasal Deformities

    ... nasal complaints. Nasal deformity can be categorized as “cosmetic” or “functional.” Cosmetic deformity of the nose results in a less ... taste , nose bleeds and/or recurrent sinusitis . A cosmetic or functional nasal deformity may occur secondary to ...

  16. Simulation Of The Synovial Fluid In A Deformable Cavity

    Martinez-Gutierrez, Nancy; Ibarra-Bracamontes, Laura A.


    The main components of a synovial joint are a cartilage and a biofluid known as the synovial fluid. The results were obtained using the FLUENT software to simulate the behavior of the synovial fluid within a deformable cavity with a simple geometry. The cartilage is represented as a porous region. By reducing the available region for the fluid, a fluid displacement into the cartilage is induced. The total pressure reached in the interface of the deformable cavity and the porous region is presented. The geometry and properties of the system are scaled to values found in a knee joint. The effect of deformation rate, fluid viscosity and properties of the porous medium on the total pressure reached are analyzed. The higher pressures are reached either for high deformation rate or when the fluid viscosity increases. This study was supported by the Mexican Council of Science and Technology (CONACyT) and by the Scientific Research Coordination of the University of Michoacan in Mexico.

  17. Performance of the experimental resins and dental nanocomposites at varying deformation rates.

    Kumar, Naresh; Shortall, Adrian


    The aim of the present study was to evaluate the bi-axial flexural strength of experimental unfilled resins and resin-based composites at varying deformation rates following 1-week dry, 1-week wet, and 13-week wet storage regimes. A total of 270 disc-shaped specimens (12 mm diameter, 1 mm thickness) of either unfilled resins or experimental resin-based composites comprising of three groups (n = 90) were fabricated. Three groups of each unfilled resin and resin-based composites (n = 90) were stored for 1 week under dry conditions, and at 1 and 13 weeks under wet conditions (37 ± 1°C) before testing. The bi-axial flexural strength of each unfilled resin and resin-based composites group was determined at a 0.1, 1, and 10 mm/min deformation rate (n = 30). The unfilled resins revealed a deformation rate dependence following all storage regimes; however, the addition of fillers in the unfilled resins modified such reliance following the 1-week dry and 13-week wet storage regimes. In contrast, a lower bi-axial flexural strength of the 1-week wet resin-based composites specimens at a 0.1 mm/min deformation rate was identified. A lower bi-axial flexural strength of the 1-week wet resin-based composites specimens at a low deformation rate suggests that premature failure of resin-based composites restorations might occur in patients with parafunctional habits, such as bruxism. © 2013 Wiley Publishing Asia Pty Ltd.

  18. Experimental study on rheological deformation and stress properties of limestone

    唐明明; 王芝银


    The systematic experiment regarding the general uniaxial compression test and the creep deformations of the typical limestones from the surrounding rock of the highway tunnels were made.The relationship between the axial stress and the delayed deformation steady value was obtained from the creep tests under low loading stresses.By the least square method,the parameters of Nishihara creep model were calculated from the creep curves.The results indicate that the strain change always lags behind the increase of stress,and the long-term strength of the limestone is about 80.6% of the stress at the volumetric strain reversal which is obtained from the conventional uniaxial compression test.

  19. Distal femoral osteotomy using a novel deformity reduction device.

    Panichi, Enrico; Cappellari, Fulvio; Olimpo, Matteo; Piras, Lisa A; Radasch, Robert; Ferretti, Antonio; Peirone, Bruno


    Distal femoral osteotomy is a surgical procedure used to correct patellar luxation, secondary to a femoral deformity. A distal femoral osteotomy using the tibial plateau levelling osteotomy-jig to temporarily provide stability of the distal femoral osteotomy, maintaining limb alignment in the frontal and axial planes prior to internal plate fixation of the osteotomy, has been described. This report describes a novel jig named Deformity Reduction Device (DRD). This device was developed with the specific aim of increasing precision and predictability during corrective osteotomy execution in order to be consistent with the preoperative planning. The distal femoral osteotomy DRD-assisted procedure is described in detail, discussing the theoretical and practical principles of the application.

  20. [Babies with cranial deformity].

    Feijen, Michelle M W; Claessens, Edith A W M Habets; Dovens, Anke J Leenders; Vles, Johannes S; van der Hulst, Rene R W J


    Plagiocephaly was diagnosed in a baby aged 4 months and brachycephaly in a baby aged 5 months. Positional or deformational plagio- or brachycephaly is characterized by changes in shape and symmetry of the cranial vault. Treatment options are conservative and may include physiotherapy and helmet therapy. During the last two decades the incidence of positional plagiocephaly has increased in the Netherlands. This increase is due to the recommendation that babies be laid on their backs in order to reduce the risk of sudden infant death syndrome. We suggest the following: in cases of positional preference of the infant, referral to a physiotherapist is indicated. In cases of unacceptable deformity of the cranium at the age 5 months, moulding helmet therapy is a possible treatment option.