Phase-transition radiation of water

The radiative relaxation mechanism of water between its different phases is studied to understand an uncommon radiation phenomenon observed in the first-order phase-transition process of water. This kind of radiation is often referred to as phase-transition radiation, whose nature is different from the Planckian radiation because its strength can be even stronger than blackbody radiation at the same temperature. In the theoretical approach of this study, analytical thermodynamic models for condensed-state water are presented to study its energetic behaviors at temperatures ranging from a few degrees K to near the critical point. Changes of energetic behaviors of water molecules during phase-transitions are of special interest and are linked to the direct emission of infrared radiation. A two-level energy transition model is proposed to investigate the characteristic radiation during vapor condensation, leading to a newly defined absorption coefficient for phase-transition radiation in the radiative transfer equation. The reported characteristic radiation for vapor condensation at wavelength 4-8 micron meter is attributed to the radiative relaxation with one hydrogen-bond formation in liquid-water during vapor condensation. In addition to the theoretical modeling, optical measurements are also included in this study to examine the energy transmission characteristics in vapor-liquid mixtures of water in the 3-5 micron meter spectral range. Results from the infrared transmission experiments and the associated theoretical predictions by the Monte Carlo radiative transfer analysis suggest that the probability for condensation radiation occurrence is one out of 20 million collisions between water-vapor molecules and liquid-water droplets

New class of 3D topological insulator in double perovskite

We predict a new class of three-dimensional topological insulators (TIs) in which the spin-orbit coupling (SOC) can more effectively generate a large band gap at $\Gamma$ point. The band gap of conventional TI such as Bi$_2$Se$_3$ is mainly limited by two factors, the strength of SOC and, from electronic structure perspective, the band gap when SOC is absent. While the former is an atomic property, we find that the latter can be minimized in a generic rock-salt lattice model in which a stable crossing of bands {\it at} the Fermi level along with band character inversion occurs for a range of parameters in the absence of SOC. Thus, large-gap TI's or TI's comprised of lighter elements can be expected. In fact, we find by performing first-principle calculations that the model applies to a class of double perovskites A$_2$BiXO$_6$ (A = Ca, Sr, Ba; X = Br, I) and the band gap is predicted up to 0.55 eV. Besides, more detailed calculations considering realistic surface structure indicate that the Dirac cones are robust against the presence of dangling bond at the boundary with a specific termination.Comment: submitted; title changed and new references added; see DOI for published versio

Enhanced call quality using user-specific voiceprint model

The audio quality of a call conducted using a user device such as a phone can be unsatisfactory due to a variety of reasons. Such reasons include noisy surroundings at the location from which the user conducts a call, position of the phone near the user’s face, users that speak with a soft voice, presence of far-end echoes, etc. This disclosure describes techniques that use a user-specific voiceprint to home into the user’s speech and cut out surrounding disturbances from a voice call. The techniques are implemented with user permission to generate and use the voiceprint

Pelvic Osteotomies for Developmental Dysplasia of the Hip

Treatment of developmental dysplasia of the hip (DDH) is based on concentric reducibility of the femoral head, patient age and the status of triradiate cartilage. Patients in walking age are indicated for pelvic osteotomy to correct the dysplastic acetabulum. Salter innominate osteotomy and Pemberton osteotomy are the most widely used procedures to treat the developmental dysplasia of the hip in early childhood. Although short-term results of the pelvic osteotomies are reported well, some long-term sequalae such as coxa valga caused by Kalamchi type II osteonecrosis of the femoral head, leg length discrepancy and impingement of hip may occur

Enhanced Distillation Under Infrared Characteristic Radiation

This chapter introduces quasi-steady water vaporization under mid-infrared (IR) radiation and the IR absorption of characteristic radiation associated with the first-kind liquid-gaseous phase transition of water. When characteristic radiation in the mid-IR spectral range is applied to water surface, the strong volumetric absorption of radiation energy in the liquid-phase causes water to be nearly isothermal. In addition to volumetric absorption, surface absorption of characteristic radiation induces vaporization of water. The complete mechanism of liquid-gaseous phase-transition radiation involves the direct surface absorption/emission of infrared energy accompanied by evaporation/condensation of water. A direct consequence of excess characteristic radiation upon water surface is the induced supersaturation. This mechanism opens up a door for enhanced distillation under characteristic radiation. Blackbody-like materials such as black anodized aluminum surfaces and metal surfaces painted in black are recommended to be heated to ~250°C to serve as economical radiation sources. For isothermal water at room temperatures, ~20% supersaturation can be induced by hemispherical Blackbody radiation with temperature ~11°C higher than the water temperature. In this situation, energy extracted from the ambient for water vaporization can be as much as 80% of latent heat. With radiation-enhanced evaporation, the production cost for distilled water is significantly reduced as compared to distillation at the boiling point

Retraction and Generalized Extension of Computing with Words

Fuzzy automata, whose input alphabet is a set of numbers or symbols, are a formal model of computing with values. Motivated by Zadeh's paradigm of computing with words rather than numbers, Ying proposed a kind of fuzzy automata, whose input alphabet consists of all fuzzy subsets of a set of symbols, as a formal model of computing with all words. In this paper, we introduce a somewhat general formal model of computing with (some special) words. The new features of the model are that the input alphabet only comprises some (not necessarily all) fuzzy subsets of a set of symbols and the fuzzy transition function can be specified arbitrarily. By employing the methodology of fuzzy control, we establish a retraction principle from computing with words to computing with values for handling crisp inputs and a generalized extension principle from computing with words to computing with all words for handling fuzzy inputs. These principles show that computing with values and computing with all words can be respectively implemented by computing with words. Some algebraic properties of retractions and generalized extensions are addressed as well.Comment: 13 double column pages; 3 figures; to be published in the IEEE Transactions on Fuzzy System