TRANSITION AND LAMINAR FLOWS IN A REALISTIC GEOMETRY OF HUMAN UPPER AIRWAY

In this study, a realistic respiratory airway model extending from oral to the end of the trachea including all the key details of the passage was produced. A series of CT scan images were used to generate the topological data of airway cross-sections that were used to generate the computational model, as well as the three-dimensional (3D) printed model of the passage for experimental study. The airflow velocity field and pressure drop in the airway for different breathing rates of 5, 7.5, 10, and 12.5[Formula: see text]L/min were investigated numerically (by laminar and transition models) and experimentally. The velocity distributions, pressure variation, and streamlines along the oral–trachea airway model were studied. The maximum pressure drop was shown to occur in the narrowest part of the larynx region. It was also concluded that the laryngeal jet could significantly influence the airway flow patterns in the trachea. A comparison between the numerical results and experimental data showed that the transition [Formula: see text]–kl–[Formula: see text] model can give better predictions of pressure losses, especially for flow rates higher than 10[Formula: see text]L/min. The simulation results for the velocity profiles in the trachea were also compared with the available particle image velocimetry (PIV) data and earlier simulations. Despite inter-personal variability and difference in the flow regime, the qualitative agreement was found.

Reflections on Termination of Linear Loops

This paper shows how techniques for linear dynamical systems can be used to reason about the behavior of general loops. We present two main results. First, we show that every loop that can be expressed as a transition formula in linear integer arithmetic has a best model as a deterministic affine transition system. Second, we show that for any linear dynamical system f with integer eigenvalues and any integer arithmetic formula G, there is a linear integer arithmetic formula that holds exactly for the states of f for which G is eventually invariant. Combining the two, we develop a monotone conditional termination analysis for general loops.

The behavior of thermodynamic kinetic on Bi2Se3 compound by 131Xe ion implantation

Thermal parameters of the [Formula: see text] compound were investigated by Differential Scanning Calorimetry (DSC) method. Four different phases were identified in the temperature range of [Formula: see text]C. Thermodynamical parameters were determined for each phase transition. [Formula: see text] samples were irradiated by 167 MeV energy [Formula: see text]Xe ions at the [Formula: see text], [Formula: see text] and [Formula: see text] ion/cm2 intensities. The DSC analyses of the irradiated samples were carried out and determined that the temperature and thermodynamical parameters of the phase transition change in the [Formula: see text] compound under the influence of swift heavy ions. The change mechanism of the thermodynamical parameters has been determined depending on the irradiation doses.

A U-spin prediction for the CP-forbidden transition e+e−→ D0D̄0 → (K+K−)D(π+π−)D

The LHCb Collaboration has recently reported the discovery of direct CP violation in combined [Formula: see text] and [Formula: see text] decay modes at the [Formula: see text] level. Assuming U-spin symmetry (i.e. [Formula: see text] interchange symmetry) for the strong-interaction parts of these two channels, we find that their corresponding direct CP-violating asymmetries are [Formula: see text] and [Formula: see text]. The CP-forbidden transition [Formula: see text] on the [Formula: see text] resonance is therefore expected to have a branching fraction of [Formula: see text] or smaller under U-spin symmetry, and it can be observed at a high-luminosity super-[Formula: see text]-charm factory if at least [Formula: see text] pairs of coherent [Formula: see text] and [Formula: see text] events are accumulated.

Calculation of Kstopped− absorption yields on light nuclei

This paper describes an atomic cascade model which is used to predict the absorption yields for a kaon at low orbits in [Formula: see text]Li,9Be,[Formula: see text]C and [Formula: see text]O nuclei. The calculations show that most of the absorptions occur in [Formula: see text] and [Formula: see text] states so that their contribution adds up to 100% for [Formula: see text]O. However, for all of the targets, absorption in the other states is nearly zero. Also by increasing atomic number of target [Formula: see text], the yield of [Formula: see text] states decreases while it increases for the [Formula: see text] states. The results also display a low sensitivity on the widths of 4[Formula: see text] state (0.1%), in which it is comparable with the natural width of the radiation transition [Formula: see text].

Effects of chemical composition and mean coordination number on glass transitions in Ge–Sb–Se glasses

Glass transitions in the Ge–Sb–Se glasses were investigated by means of differential scanning calorimetry (DSC) under non-isothermal conditions. The glass transition temperature [Formula: see text], activation energy of glass transition [Formula: see text], and fragility index as functions of the mean coordination number (MCN) and atomic percent of Ge were examined. The maximum value of [Formula: see text] in each group of the glasses occurred at the chemically stoichiometric composition, suggesting a glass transition threshold. The [Formula: see text] and fragility index were calculated from the heating rate dependence of [Formula: see text]. Both [Formula: see text] and fragility index show the minima at MCN = 2.4 which can be attributed to the structural phase transition of a covalently glassy network at MCN = 2.4. The analysis of the experimental results suggests that both the chemical composition and MCN have significant effects on the glass transitions in Ge–Sb–Se glasses.

SU(3) Polyakov linear-sigma model: Conductivity and viscous properties of QCD matter in thermal medium

In mean field approximation, the grand canonical potential of SU(3) Polyakov linear-[Formula: see text] model (PLSM) is analyzed for chiral phase transition, [Formula: see text] and [Formula: see text] and for deconfinement order-parameters, [Formula: see text] and [Formula: see text] of light- and strange-quarks, respectively. Various PLSM parameters are determined from the assumption of global minimization of the real part of the potential. Then, we have calculated the subtracted condensates [Formula: see text]. All these results are compared with recent lattice QCD simulations. Accordingly, essential PLSM parameters are determined. The modeling of the relaxation time is utilized in estimating the conductivity properties of the QCD matter in thermal medium, namely electric [Formula: see text] and heat [Formula: see text] conductivities. We found that the PLSM results on the electric conductivity and on the specific heat agree well with the available lattice QCD calculations. Also, we have calculated bulk and shear viscosities normalized to the thermal entropy, [Formula: see text] and [Formula: see text], respectively, and compared them with recent lattice QCD. Predictions for [Formula: see text] and [Formula: see text] are introduced. We conclude that our results on various transport properties show some essential ingredients, that these properties likely come up with, in studying QCD matter in thermal and dense medium.

Scheelite (CaWO4)-type microphosphors: Facile synthesis, structural characterization and photoluminescence properties

Scheelite (CaWO4)-type microphosphors were synthesized by the precipitation method assisted with cetyltrimethyl ammonium bromide (CTAB). All compounds crystallized in the tetragonal structure with space group [Formula: see text] (No. 88). FE-SEM micrographs illustrate the spherical-like morphologies and rough surface. PL spectra indicate the broad emission peak maximum at 613 nm under UV excitation. Luminescence decay curves monitored by [Formula: see text] transition ([Formula: see text] nm) of Eu[Formula: see text] in doped CaWO4 are presented, the curves exhibit a single-exponential feature and the lifetime for doped CaWO4 is 0.61 ms.

Effect of Sr2TiMnO6 fillers on mechanical, dielectric and thermal behaviour of PMMA polymer

Composites of poly(methyl methacrylate) (PMMA) and [Formula: see text] (STMO) were fabricated via melt mixing followed by hot pressing technique. These were characterized using X-ray diffraction (XRD), thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC), thermo mechanical analysis (TMA) and impedance analyser for their structural, thermal and dielectric properties. The coefficient of thermal expansion (CTE) was measured between 40°C and 100°C for pure PMMA is 115.2 ppm/°C, which was decreased to 78.58 ppm/°C when the STMO content was increased to 50 wt.% in PMMA. There was no difference in the glass transition ([Formula: see text]) temperature of the PMMA polymer and their composites. However, the FTIR analysis indicated possible interaction between the PMMA and STMO. The density and the hardness were increased as the STMO content increased in the PMMA matrix. Permittivity was found to be as high as 30.9 at 100 Hz for the PMMA+STMO-50 wt.% composites, indicating the possibility of using these materials for capacitor applications. The thermal stability of polymer was enhanced by incorporation of STMO fillers.