Publications by authors named "Hong-liang Yi"

Charge-order states of broken symmetry, such as charge density wave (CDW), are able to induce exceptional physical properties, however, the precise understanding of the underlying physics is still elusive. Here, we combine fluctuational electrodynamics and density functional theory to reveal an unconventional thermophotonic effect in CDW-bearing TiSe_{2}, referred to as thermophotonic-CDW (tp-CDW). The interplay of plasmon polariton and CDW electron excitations give rise to an anomalous negative temperature dependency in thermal photons transport, offering an intuitive fingerprint for a transformation of the electron order.

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The hydrodynamic behavior of phonons is of particular interest and importance owing to the strong demand for highly thermal conductive materials. Thermal transport in hydrodynamic regime becomes essentially nonlocal, which can give rise to a number of new and counterintuitive phenomena. In this work, we present a direct numerical study of nonlocal phonon thermal transport in graphene ribbon with vicinity geometry based on the phonon Boltzmann transport equation with first-principles inputs.

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In this paper, a direct numerical simulation (DNS) of dielectric fluid flow subjected to unipolar injection under an alternating current (AC) electric field is carried out. The effect of frequency of pulsed direct current (PDC) and AC on the transient evolution of electroconvection and their subcritical bifurcations are investigated in details. Electroconvection under PDC or AC tends to exhibit oscillating flow due to the periodic boundary condition of charge density and potential compared to the direct current (DC) case.

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In this work, a two-dimensional droplet confined between two parallel electrodes under the combined effects of a nonuniform electric field and unipolar charge injection is numerically investigated using the lattice Boltzmann method (LBM). Under the non-Ohmic regime, the interfacial tension and electric forces at the droplet surface cooperate with the volumetric Coulomb force, leading to complex deformation and motion of the droplet while at the same time inducing a bulk electroconvective flow. After we validate the model by comparing with analytical solutions at the hydrostatic state, we perform a quantitative analysis on the droplet deformation factor D and bulk flow stability criteria T_{c} under different parameters, including the electric capillary number Ca, the electric Rayleigh number T, the permittivity ratio ɛ_{r}, and the mobility ratio K_{r}.

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Direct numerical simulations of electroconvection instability near an ion-selective surface are conducted using a mesoscopic lattice Boltzmann method (LBM). An electrohydrodynamic model of ion transport and fluid flow is presented. We numerically solve the Poisson-Nernst-Planck equations for the electric field and the Navier-Stokes equations for the flow field.

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Owing to a high electromagnetic confinement and a strong photonic density of states, hyperbolic surface plasmon polaritons (HSPPs) provide a fascinating promise for applications in thermal photonics. In this work, we theoretically predict a possibility for the improvement of the near-field radiative heat transfer on the basis of tailoring the electromagnetic state of hyperbolic metasurfaces by the uniaxial hyperbolic substrate. By using the photonic tunneling coefficient and the polaritons dispersion, we present a comprehensive study of the hybrid effect of the hyperbolic substrate on HSPPs.

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Purpose: This study aimed to analyze a Chinese institution's experience with managing cervical necrotizing fasciitis (CNF) and observe the effects of a new therapeutic approach for postoperative drainage system.

Methods: A retrospective study was established including a total of 46 CNF patients who underwent surgical debridement between April 2006 and April 2018. Analyses of demographic data, etiology, comorbidity, microbiology, complications, treatment methods, duration of treatment, and treatment outcomes were obtained.

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Melting in the presence of electrohydrodynamic (EHD) flow driven by the Coulomb force in dielectric phase change material is numerically studied. A model is developed for the EHD flow in the solid-liquid phase change process. The fully coupled equations including mechanical equations, electrical equations, energy equations, and the continuity equations in the solid-liquid interface are solved using a unified lattice Boltzmann model (LBM).

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The radiative transfer equation (RTE) has two asymptotic regimes characterized by the optical thickness, namely, optically thin and optically thick regimes. In the optically thin regime, a ballistic or kinetic transport is dominant. In the optically thick regime, energy transport is totally dominated by multiple collisions between photons; that is, the photons propagate by means of diffusion.

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Background: Standard management has been recommended for obstructive sleep apnea (OSA) by several guidelines, but patient choice in the practical setting is unclear.

Methods: A survey nested in two prospective cohort studies of OSA (enrollment: 2001-2010) in China. The last interview was conducted between July 2014 and May 2015, using a comprehensive 10-point questionnaire administered in a face-to-face or telephone interview, and assessed (I) whether the participant had received any OSA treatment; (II) why he or she had decided for or against treatment; (III) what treatment was received; (IV) whether the participant used continuous positive airway pressure (CPAP) or OA daily; and (V) the perceived efficacy of therapy.

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Transient/time-dependent radiative transfer in a two-dimensional scattering medium is numerically solved by the discontinuous finite element method (DFEM). The time-dependent term of the transient vector radiative transfer equation is discretized by the second-order central difference scheme and the space domain is discretized into non-overlapping quadrilateral elements by using the discontinuous finite element approach. The accuracy of the transient DFEM model for the radiative transfer equation considering the polarization effect is verified by comparing the time-resolved Stokes vector component distributions against the steady solutions for a polarized radiative transfer problem in a two-dimensional rectangular enclosure filled with a scattering medium.

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Transient (time-dependent) polarized radiative transfer in a scattering medium exposed to an external collimated beam illumination is conducted based on the time-dependent polarized radiative transfer theory. The transient term, which persists the nanosecond order time and cannot be ignored for the time-dependent radiative transfer problems induced by a short-pulsed beam, is considered as well as the polarization effect of the radiation. A discontinuous finite element method (DFEM) is developed for the transient vector radiative transfer problem and the derivation of the discrete form of the governing equation is presented.

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Transient radiative transfer induced by a short-pulsed laser in a one-dimensional graded-index medium is investigated by the discontinuous finite element method (DFEM). The boundaries of the medium are Fresnel reflectors, and the incident pulse is considered as the combination of the collimated and the diffuse parts after its first interaction with the medium. The correctness and accuracy of the DFEM solutions for time-resolved reflectance and transmittance are first validated by comparisons with the results obtained by the Monte Carlo method, and the DFEM is then employed to investigate the transient radiative transfer in a graded-index medium with Fresnel boundaries.

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A complete lattice Boltzmann model (LBM) is proposed for the steady radiative transfer equation (RTE). The RTE can be regarded as a pure convection equation with a source term. To derive the expressions for the equilibrium distribution function and the relaxation time, an artificial isotropic diffusion term is introduced to form a convection-diffusion equation.

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The vector radiative transfer problem in a vertically multilayer scattering medium with spatial changes in the index of refraction is solved by the natural element method (NEM). The top boundary of the multilayer medium is irradiated by a collimated beam. In our model, the angular space is discretized by the discrete ordinates approach, and the spatial discretization is conducted by the Galerkin weighted residuals approach.

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In this paper, we developed a unified lattice Boltzmann model (LBM) to simulate electroconvection in a dielectric liquid induced by unipolar charge injection. Instead of solving the complex set of coupled Navier-Stokes equations, the charge conservation equation, and the Poisson equation of electric potential, three consistent lattice Boltzmann equations are formulated. Numerical results are presented for both strong and weak injection regimes, and different scenarios for the onset and evolution of instability, bifurcation, and chaos are tracked.

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A local radial basis function meshless scheme (LRBFM) is developed to solve polarized radiative transfer in participating media containing randomly oriented axisymmetric particles in which radial basis functions augmented with polynomial basis are employed to construct the trial functions, and the vector radiative-transfer equation based on the discrete-ordinates approach is discretized directly by collocation method. The LRBFM belongs to a class of truly meshless methods that do not need any mesh or any numerical integration scheme. Performances of the LRBFM are verified with analytical solutions and other numerical results reported earlier in the literature via five various test cases.

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The natural element method (NEM) is extended to solve transient radiative transfer (TRT) in two-dimensional semitransparent media subjected to a collimated short laser irradiation. The least-squares (LS) weighted residuals approach is employed to spatially discretize the transient radiative heat transfer equation. First, for the case of the refractive index matched boundary, LSNEM solutions to TRT are validated by comparison with results reported in the literature.

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Polarized radiative transfer in a multilayer system is an important problem and has wide applications in various fields. In this work, a Monte Carlo (MC) model is developed to simulate polarized radiative transfer in a semitransparent arbitrary multilayer medium with different refractive indices in each layer. Two kinds of polarization mechanisms are considered: scattering by particles and reflection and refraction at the Fresnel surfaces or interfaces.

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Within a gradient-index medium, the radiative rays propagate in curved paths, which makes polarized states change continuously and the solution to the radiative transfer be thus more complex and difficult. In this paper, an arbitrary multilayer model is developed to approximately simulate vector (polarized) radiative transfer in a gradient-index plane-parallel medium. The gradient-index medium is divided into an arbitrary number of sublayers, and each sublayer has a uniform refractive index and two virtual Fresnel's interfaces where only transmission (refraction) is considered.

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The aim of this study was to determine the associated factors affecting the outcome of uvulopharyngopalatoplasty (UPPP) in patients with severe obstructive sleep apnea hypopnea syndrome (OSAHS), and to investigate whether cephalometric measurements were predictive of the therapeutic response to UPPP in patients with severe OSAHS. We retrospectively studied 51 consecutive patients who underwent revised UPPP with uvula preservation (H-UPPP), or Z-palatopharyngoplasty (ZPPP) for severe OSAHS [apnea-hypopnea index (AHI) >30]. All patients were evaluated using physical examination, Epworth Sleepiness Scale (ESS), cephalometry, and nocturnal polysomnography (PSG) before surgery and at 6-12 months after surgery.

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Background: This study aimed to evaluate the efficacy and safety of primary maxillomandibular advancement (MMA) with concomitant adjunctive revised uvulopalatopharyngoplasty with uvula preservation (H-UPPP) in selected patients with severe obstructive sleep apnea-hypopnea syndrome (OSASH).

Methods: Eleven consecutive male patients with velo-orohypopharyngeal and hypopharyngeal narrowing underwent MMA with concomitant H-UPPP for severe OSAHS. All patients underwent a physical examination, Epworth Sleepiness Scale evaluation, cephalometry, nocturnal polysomnogram, and velopharyngeal insufficiency questionnaire survey before and at 6 to 12 months after surgery.

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Objective: To identify a correlation in terms of airway obstruction between awake and sleep apnea using spiral computed tomography (CT).

Study Design: Case series with planned data collection.

Setting: College medical center.

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Objectives: To investigate predictors of surgical outcomes of uvulopalatopharyngoplasty (UPPP) for obstructive sleep apnea hypopnea syndrome (OSAHS).

Study Design: Case series with planned data collection.

Setting: A university medical center.

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Objective: To explore the feasibility and efficiency of Z-palato-pharyngoplasty (ZPPP) plus genioglossus advancement and hyoid suspension (GAHM) for severe obstructive sleep apnea hypopnea syndrome (OSAHS).

Study Design: Case series with planned data collection.

Setting: A university medical center.

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