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In the present paper, we have calculated the phonon dispersion relations, phonon density of states, Debye characteristic temperature and the zone boundary phonons for group-III nitrides AN (A = B, Al, Ga and In) using eleven-parameter three-body shell model with both the ions being polarizable. Our calculated results are in good agreement with experimental results available in the literature.  相似文献   
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Extremity fractures are common in patients with traumatic brain injuries (TBIs). These injuries are often inadequately treated and occasionally are completely missed due to the unique problems inherent to the TBI patient. However, appropriate evaluation of the TBI patient allows prompt diagnosis and optimal treatment of extremity fractures. The increased survival rate of these patients has resulted in a greater emphasis on minimizing dysfunction and disability, especially that due to concomitant orthopaedic trauma. Advances in anesthestic technique permit earlier operative fixation of extremity fractures. Most injuries, particularly those in the lower extremity, require operative stabilization to allow early mobilization and rehabilitation. Upper extremity fractures are often associated with peripheral nerve injuries. Heterotopic ossification is common, especially about the elbow and hip. Contrary to prevalent belief, fracture healing is not necessarily accelerated in the TBI patient; hypertrophic callus, myositis ossificans, and heterotopic ossification occur frequently and are often misperceived as accelerated healing.  相似文献   
75.
The deposition velocities of 222Rn (radon) and 220Rn (thoron) progeny species have been measured in a chamber, in a test house, and in dwellings by relating the atom deposition fluxes of these species to their atom concentrations in air. These measurements were carried out using absorber-mounted nuclear track detectors (LR-115) which selectively register the tracks due to alpha emissions from 212Po and 214Po from the deposited atoms of 220Rn and 222Rn progeny species, respectively. These are termed as DRPS (direct radon progeny sensor) and DTPS (direct thoron progeny sensor). Measurement of parameters such as ventilation rate, particle size distribution and unattached fractions were also carried out along with deposition velocity. The experimental data on deposition velocity in test house and chamber were compared with the predictions based on the indoor progeny dynamics model and particle deposition models. These showed excellent agreement with experimental values although the data on radon progeny showed slightly higher dispersion. The progeny deposition velocities were also measured in living rooms of dwellings in Mumbai and were found to be close to the model results which in turn imply that in the long term, the average environmental conditions are similar to that in the test house. These results point at a plausible constancy of long time averaged indoor deposition velocities. From these studies, we are inclined to assign summary values of deposition velocities of 0.075 m h?1 for 220Rn progeny and 0.132 m h?1 for 222Rn progeny, for indoor conditions.  相似文献   
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Multimedia Tools and Applications - Various Human Activities are classified through time-series data generated by the sensors of wearable devices. Many real-time scenarios such as Healthcare...  相似文献   
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RGB-D sensors have been in great demand due to its capability of producing large amount of multimodal data like RGB images and depth maps, useful for bette  相似文献   
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In this study the momentum and energy equations are solved to analyze the flow between two parallel plates by employing second‐order velocity slip and temperature jump conditions. The flow is considered to be laminar, incompressible, hydrodynamically/thermally fully developed, and steady state. In addition to the isoflux condition, viscous dissipation is included in the analysis. Closed form expressions for the temperature field and Nusselt number are obtained as a function of the Knudsen number and Brinkman number. The Nusselt number obtained by employing the second‐order model is found to be lower compared to the continuum value and agrees well with the other theoretical models. © 2013 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.21116  相似文献   
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The present study deals with numerical investigations of the boiling phenomena over a spherical surface at different degrees of superheat (ΔT), varying from 10 to 500 K. Various phenomena like vapor sliding, bubble formation, pinch-off, induced vorticity have been illustrated for a deep understanding of the boiling process over a spherical surface. The effect of the degree of superheat on the bubble pinch-off time and volume is also investigated. Further, reported the spatial observation of vapor sliding and retention over the surface with time scale, overall and average characteristics. The fast Fourier transform of a spaced average void fraction of liquid and Nusselt number showed the dominance of film boiling with respect to the degree of superheat. As the degree of superheat increases, the vapor generation rate also increases, which produces a more vapor–liquid interface. Further, with an increase in the degree of superheat, the vapor generation progression shifted from linear to nonlinear patterns. A sphere with ΔT = 500 K generated 32.59 times more vapor than a sphere with ΔT = 10 K. It is found that the vapor generation is dependent on the degree of superheating and exposed time for heating. Thus, a correlation and artificial neural network model have been developed to predict vapor generation during boiling over the spherical surface as a function of time and degree of superheat.  相似文献   
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