The Experts below are selected from a list of 64911 Experts worldwide ranked by ideXlab platform

S L Ban - One of the best experts on this subject based on the ideXlab platform.

  • optical phonons and their transformation in cylindrical wurtzite core multishell nanowires with ternary mixed crystal effect
    Journal of Applied Physics, 2020
    Co-Authors: J X Wang, S L Ban
    Abstract:

    The whole optical phonon spectrum of quasiconfined (CO), propagating (PR), and interface (IF) modes in wurtzite III-nitride cylindrical core-multishell nanowires (CMSNWs) is obtained based on the dielectric continuum and Loudon's uniaxial crystal models considering the ternary mixed crystal effect. A transfer matrix method calculation shows that there are six types of CO modes and one type of PR mode in a three-layered CMSNW. For any Fixed Component, only permitted types of CO modes exist in allowable frequency regions, while the PR modes appear only when Components are almost the same in all layers, originating from anisotropic optical phonons in bulk wurtzite nitride. The whole spectrum reveals two mode transformations: one is between PR and IF modes by adjusting Components in different layers; the other is continuous among five possible modes at any Fixed Component with connected frequency regions. The dispersion relations and corresponding electrostatic potentials of the whole optical phonon spectrum are helpful to understand the frequency-dependent electron–phonon interaction in the future. The analysis process can be extended to arbitrary nitride cylindrical CMSNWs for the modulation of optical phonon related properties.

  • optical phonons and their transformation in cylindrical wurtzite core multishell nanowires with ternary mixed crystal effect
    Journal of Applied Physics, 2020
    Co-Authors: J X Wang, S L Ban
    Abstract:

    The whole optical phonon spectrum of quasiconfined (CO), propagating (PR), and interface (IF) modes in wurtzite III-nitride cylindrical core-multishell nanowires (CMSNWs) is obtained based on the dielectric continuum and Loudon's uniaxial crystal models considering the ternary mixed crystal effect. A transfer matrix method calculation shows that there are six types of CO modes and one type of PR mode in a three-layered CMSNW. For any Fixed Component, only permitted types of CO modes exist in allowable frequency regions, while the PR modes appear only when Components are almost the same in all layers, originating from anisotropic optical phonons in bulk wurtzite nitride. The whole spectrum reveals two mode transformations: one is between PR and IF modes by adjusting Components in different layers; the other is continuous among five possible modes at any Fixed Component with connected frequency regions. The dispersion relations and corresponding electrostatic potentials of the whole optical phonon spectrum are helpful to understand the frequency-dependent electron–phonon interaction in the future. The analysis process can be extended to arbitrary nitride cylindrical CMSNWs for the modulation of optical phonon related properties.The whole optical phonon spectrum of quasiconfined (CO), propagating (PR), and interface (IF) modes in wurtzite III-nitride cylindrical core-multishell nanowires (CMSNWs) is obtained based on the dielectric continuum and Loudon's uniaxial crystal models considering the ternary mixed crystal effect. A transfer matrix method calculation shows that there are six types of CO modes and one type of PR mode in a three-layered CMSNW. For any Fixed Component, only permitted types of CO modes exist in allowable frequency regions, while the PR modes appear only when Components are almost the same in all layers, originating from anisotropic optical phonons in bulk wurtzite nitride. The whole spectrum reveals two mode transformations: one is between PR and IF modes by adjusting Components in different layers; the other is continuous among five possible modes at any Fixed Component with connected frequency regions. The dispersion relations and corresponding electrostatic potentials of the whole optical phonon spectrum ...

J X Wang - One of the best experts on this subject based on the ideXlab platform.

  • optical phonons and their transformation in cylindrical wurtzite core multishell nanowires with ternary mixed crystal effect
    Journal of Applied Physics, 2020
    Co-Authors: J X Wang, S L Ban
    Abstract:

    The whole optical phonon spectrum of quasiconfined (CO), propagating (PR), and interface (IF) modes in wurtzite III-nitride cylindrical core-multishell nanowires (CMSNWs) is obtained based on the dielectric continuum and Loudon's uniaxial crystal models considering the ternary mixed crystal effect. A transfer matrix method calculation shows that there are six types of CO modes and one type of PR mode in a three-layered CMSNW. For any Fixed Component, only permitted types of CO modes exist in allowable frequency regions, while the PR modes appear only when Components are almost the same in all layers, originating from anisotropic optical phonons in bulk wurtzite nitride. The whole spectrum reveals two mode transformations: one is between PR and IF modes by adjusting Components in different layers; the other is continuous among five possible modes at any Fixed Component with connected frequency regions. The dispersion relations and corresponding electrostatic potentials of the whole optical phonon spectrum are helpful to understand the frequency-dependent electron–phonon interaction in the future. The analysis process can be extended to arbitrary nitride cylindrical CMSNWs for the modulation of optical phonon related properties.

  • optical phonons and their transformation in cylindrical wurtzite core multishell nanowires with ternary mixed crystal effect
    Journal of Applied Physics, 2020
    Co-Authors: J X Wang, S L Ban
    Abstract:

    The whole optical phonon spectrum of quasiconfined (CO), propagating (PR), and interface (IF) modes in wurtzite III-nitride cylindrical core-multishell nanowires (CMSNWs) is obtained based on the dielectric continuum and Loudon's uniaxial crystal models considering the ternary mixed crystal effect. A transfer matrix method calculation shows that there are six types of CO modes and one type of PR mode in a three-layered CMSNW. For any Fixed Component, only permitted types of CO modes exist in allowable frequency regions, while the PR modes appear only when Components are almost the same in all layers, originating from anisotropic optical phonons in bulk wurtzite nitride. The whole spectrum reveals two mode transformations: one is between PR and IF modes by adjusting Components in different layers; the other is continuous among five possible modes at any Fixed Component with connected frequency regions. The dispersion relations and corresponding electrostatic potentials of the whole optical phonon spectrum are helpful to understand the frequency-dependent electron–phonon interaction in the future. The analysis process can be extended to arbitrary nitride cylindrical CMSNWs for the modulation of optical phonon related properties.The whole optical phonon spectrum of quasiconfined (CO), propagating (PR), and interface (IF) modes in wurtzite III-nitride cylindrical core-multishell nanowires (CMSNWs) is obtained based on the dielectric continuum and Loudon's uniaxial crystal models considering the ternary mixed crystal effect. A transfer matrix method calculation shows that there are six types of CO modes and one type of PR mode in a three-layered CMSNW. For any Fixed Component, only permitted types of CO modes exist in allowable frequency regions, while the PR modes appear only when Components are almost the same in all layers, originating from anisotropic optical phonons in bulk wurtzite nitride. The whole spectrum reveals two mode transformations: one is between PR and IF modes by adjusting Components in different layers; the other is continuous among five possible modes at any Fixed Component with connected frequency regions. The dispersion relations and corresponding electrostatic potentials of the whole optical phonon spectrum ...

Ronnie Sadka - One of the best experts on this subject based on the ideXlab platform.

  • momentum and post earnings announcement drift anomalies the role of liquidity risk
    Journal of Financial Economics, 2006
    Co-Authors: Ronnie Sadka
    Abstract:

    Abstract This paper investigates the Components of liquidity risk that are important for understanding asset-pricing anomalies. Firm-level liquidity is decomposed into variable and Fixed price effects and estimated using intraday data for the period 1983–2001. Unexpected systematic (market-wide) variations of the variable Component rather than the Fixed Component of liquidity are shown to be priced within the context of momentum and post-earnings-announcement drift (PEAD) portfolio returns. As the variable Component is typically associated with private information [e.g., Kyle, 1985. Econometrica 53, 1315–1335], the results suggest that a substantial part of momentum and PEAD returns can be viewed as compensation for the unexpected variations in the aggregate ratio of informed traders to noise traders.

  • momentum and post earnings announcement drift anomalies the role of liquidity risk
    2003
    Co-Authors: Ronnie Sadka
    Abstract:

    This paper investigates the Components of liquidity risk that are important for asset-pricing anomalies. Firm-level liquidity is decomposed into variable and Fixed price effects and estimated using intraday data for the period 1983-2001. Unexpected systematic (market-wide) variations of the variable Component rather than the Fixed Component of liquidity are shown to be priced within the context of momentum and post-earnings-announcement drift (PEAD) portfolio returns. As the variable Component is typically associated with private information (e.g., Kyle (1985)), the results suggest that a substantial part of momentum and PEAD returns can be viewed as compensation for the unexpected variations in the aggregate ratio of informed traders to noise traders.

Leo A Whiteside - One of the best experts on this subject based on the ideXlab platform.

  • contact stress analysis in meniscal bearing total knee arthroplasty
    Journal of Arthroplasty, 1998
    Co-Authors: Shuichi Matsuda, Stephen E White, Victor G Williams, Daniel S Mccarthy, Leo A Whiteside
    Abstract:

    Abstract The effect of a mobile meniscal bearing on tibiofemoral contact stress was tested with a standard Fixed tibial Component and with movable tibial Components (anteroposterior sliding, rotationally sliding, and anteroposterior and rotationally sliding). A digital electronic sensor was used to detect tibiofemoral contact location in five cadaver knees, then the location was reproduced while peak and mean stresses were measured under compressive load at 0°, 30°, 60°, and 90° of flexion. Stresses were measured when the tibial Component was normally aligned and at 15° internal and 15° external rotation. To evaluate the effect of excessive overhang of the polyethylene articular surface, undersurface stress of the rotationally sliding Component was also measured with a 30° and a 45° malrotated tibial tray. Uppersurface stresses of the Fixed-bearing Components were significantly higher at full extension than those recorded in Components with rotational mobility. Undersurface stresses were always lower than uppersurface stresses, but correlated with uppersurface stresses. Undersurface stresses of the rotationally sliding Component gradually increased as the malrotation angle of the tray increased. A mobile meniscal bearing surface appears to offer an advantage over a standard Fixed Component when rotational malalignment of the tibial Component occurs. However, with severe rotational malalignment, edge contact markedly increases undersurface stresses, which could cause deformity and subluxation.

Robert T Trousdale - One of the best experts on this subject based on the ideXlab platform.

  • cementation of a dual mobility construct in recurrently dislocating and high risk patients undergoing revision total arthroplasty
    Journal of Arthroplasty, 2017
    Co-Authors: Brian P Chalmers, Cameron K Ledford, Michael J Taunton, Rafael J Sierra, David G Lewallen, Robert T Trousdale
    Abstract:

    Abstract Background Recurrent instability remains a challenge after revision total hip arthroplasty (THA). We report the outcomes of cementing a cementless dual mobility (DM) Component into a stable acetabular shell for the treatment and/or prevention of instability in revision THA. Methods Eighteen patients (18 THAs) undergoing revision THA with a specific monoblock DM construct cemented into a new acetabular Component or an existing well-Fixed Component from 2011 to 2014 were retrospectively reviewed. Tumor prostheses and total femoral replacements were excluded. In 9 patients (50%), Components were implanted specifically for recurrent dislocations. Mean age was 64 years; mean follow-up was 3 years. Patients underwent an average of 4 prior hip operations (range 2-6). Results No cemented DM cups dissociated at the cement-cup interface. Three patients (17%) experienced a postoperative dislocation. One required a revision to constrained liner and 2 underwent open reduction with retention of the DM construct. Harris Hip Scores improved from 53 to 82 postoperatively (P Conclusion Cementation of a monoblock cup DM construct, an off-label use as the construct is not specifically made for cementation, into a well-Fixed acetabular Component provides an alternative to enhance prosthetic stability in (1) recurrently dislocating THAs with well Fixed, well-positioned acetabular Components and (2) complex acetabular reconstructions in which constraint should be avoided. While not a perfect solution in this series, DM constructs provide a number of advantages including no added constraint at the interface and a large effective femoral head to diminish prosthetic impingement.