Intelligibilities of 1-octave rectangular bands spanning the speech spectrum when heard separately and paired

There is a need, both for speech theory and for many practical applications, to know the intelligibilities of individual passbands that span the speech spectrum when they are heard singly and in combination. While indirect procedures have been employed for estimating passband intelligibilities (e.g., the Speech Intelligibility Index), direct measurements have been blocked by the confounding contributions from transition band slopes that accompany filtering. A recent study has reported that slopes of several thousand dBA/octave produced by high-order finite impulse response filtering were required to produce the effectively rectangular bands necessary to eliminate appreciable contributions from transition bands [Warren et al., J. Acoust. Soc. Am. 115, 1292-1295 (2004)]. Using such essentially vertical slopes, the present study employed sentences, and reports the intelligibilities of their six 1-octave contiguous passbands having center frequencies from 0.25 to 8 kHz when heard alone, and for each of their 15 possible pairings.     

Loudness growth in 1/2-octave bands (LGOB)--a procedure for the assessment of loudness

In this paper, a method that has been developed for the assessment and quantification of loudness perception in normal-hearing and hearing-impaired persons is described. The method has been named LGOB, which stands for loudness growth in 1/2-octave bands. The method uses 1/2-octave bands of noise, centered at 0.25, 0.5, 1.0, 2.0, and 4.0 kHz, with subjective levels between a subject's threshold of hearing and the "too loud" level. The noise bands are presented to the subject, randomized over frequency and level, and the subject is asked to respond with a loudness rating (one of: VERY SOFT, SOFT, OK, LOUD, VERY LOUD, TOO LOUD). Subject responses (normal and hearing-impaired) are then compared to the average responses of a group of normal-hearing subjects. This procedure allows one to estimate the subject's loudness growth relative to normals, as a function of frequency and level. The results may be displayed either as isoloudness contours or as recruitment curves. In its present form, the measurements take less than 30 min. The signal presentation and analysis is done using a PC and a PC plug-in board having a digital to analog converter.     

A contribution to the question of the frequencies of piezoelectric plates

The relations between the frequencies of a piezoelectric plate excited in various orders of resonances and the frequency dependences on the air-gap were studied. These equations were derived from the proposed model and were proved experimentally. The theory and experiment are in good agreement.     

Interface traps contribution to capacitance of Al2O3/(GaN)AlGaN/GaN heterostructures at low frequencies

Influence of interface traps at Al₂O₃/(GaN)/AlGaN interface on low and high frequency capacitance of Al₂O₃/(GaN)/AlGaN/GaN heterostructure capacitor was studied. New features were observed in the capacitance curves. Obtained experimental results were modeled and simulated and accordance with the experiment has been obtained. For lower frequencies a new capacitance peak in the depletion and increase of the capacitance in a plateau region were measured. The capacitance peak in the depletion region was successfully explained by a capacitance response of the interface traps with U-shape density distribution. On the other hand the increase of the capacitance plateau was modeled by the homogeneous interface trap distribution. We assume that the traps located near the band edges having the highest density are able to respond to the low frequency measuring.     

Cascade fluorescent decay in Pr3+-doped fluorides: Achievement of a quantum yield greater than unity for emission of visible light

Studies of the fluorescence spectrum of Pr³⁺ under excitation with the 185 nm resonance line of Hg have been made in a number of fluoride host lattices. In some of these phosphors such as YF₃ and LaF₃ the radiative decay originates in the ¹S₀ level of Pr³⁺ and proceeds via a simple cascade process in which, for some of the decay paths, two visible photons are emitted. In other hosts such as LiYF₄ the fluorescence originates in the 4f5d levels and consists of four principal bands in the ultraviolet. A third type of host exhibits a mixture of these two types of emission. In one phosphor of the first type, YF₃ activated with 0.1 mol % Pr³⁺, an overall quantum yield of 1.4 ± 0.15 for visible light has been measured at room temperature.     

腔外原子操作控制腔内原子的纠缠特性

考虑初始处于W态的三个二能级原子,将其中两个原子同时分别注入处于真空态的两个腔中并发生共振相互作用的情况.采用数值计算方法,研究了对腔外原子的旋转操作和测量对腔内原子纠缠性质的影响.研究结果表明,通过对腔外原子的旋转操作和选择性测量可控制腔内原子的纠缠性质.     

Zone center frequencies of the orthorhombic NdMnO3 perovskite

A short range force constant model has been applied for the first time to investigate the phonons in NdMnO₃ perovskite in the orthorhombic phase. The calculations with nine stretching and eight bending force constants provide good agreement for the observed Raman frequencies. The infrared frequencies have been assigned for the first time.     

Dielectric properties of BiMg1/2Ti1/2O3 and BiMg1/2Zr1/2O3 perovskite ceramics with elimination of the contribution for direct current conductivity

A technique for analysis of the electric modulus spectrum of dielectric ceramics based on the elimination of the direct current conductivity (σ _dc ) contribution has been developed. Expressions are given for the real (M′ _ac ) and imaginary (M′′ _ac ) parts of the complex electrical modulus related only to the dielectric polarization and not containing the contribution of σ _dc . The frequency dependence of M′′ _ac and the M′′ _ac – M′ _ac diagram for BiMg_1/2Ti_1/2O₃ and BiMg_1/2Zr_1/2O₃ perovskite ceramics are analyzed.     

Luminescence properties of K1/2Bi1/2TiO3:Pr3+ and Na1/2Bi1/2TiO3:Pr3+

The luminescence properties of K(1/2)Bi(1/2)TiO(3):Pr(3+) and Na(1/2)Bi(1/2)TiO(3):Pr(3+) powders are investigated in the temperature range 10-600 K. The experimental data are interpreted on the basis of metal-to-metal charge transfer processes and by considering Bi(3+)-to-Pr(3+) sensitization effects.     

Computing the Maslov index of solitary waves, Part 2: Phase space with dimension greater than four

This paper extends the theory of the Maslov index of solitary waves in Part 1 to the case where the phase space is of dimension greater than four. The starting point is Hamiltonian PDEs, in one space dimension and time, whose steady part is a Hamiltonian ODE with a phase space of dimension six or greater. This steady Hamiltonian ODE is the main focus of the paper. Homoclinic orbits of the steady ODE represent solitary waves of the PDE, and one of the properties of the homoclinic orbits is the Maslov index. We develop formulae for the Maslov index, the Maslov angle and its subangles, in an exterior algebra framework, and develop numerical algorithms to compute them. In addition, a new numerical approach based on a discrete QR algorithm is proposed. The Maslov index is of interest for classifying solitary waves and as an indicator of stability or instability of the solitary wave in the time-dependent problem. The theory is applied to a class of reaction-diffusion equations, the longwave-shortwave resonance equations and the seventh-order KdV equation.     

Anelastic relaxation of Pr1/2Ca1/2MnO3 at low and medium frequencies in the 350–500 K range

In previous works (Jornadas SAM 2000; J. Magn. Magn. Mater. 226–230 (2001) 988) the low-frequency anelastic effects of two manganite perovskites of La_2/3Sr_1/3MnO₃ and La_2/3Ca_1/3MnO₃ were studied at 1 Hz and temperatures above those of the metal–insulator transition. An important internal friction peak (P1) appears at 414 and 419 K, respectively, with a modulus variation and no appreciable contribution to electrical resistivity. Another compound Pr_1/2Ca_1/2MnO₃ of the same family has been studied by anelastic mechanical spectroscopy in order to add new data which could elucidate the (P1) peak mechanism. The measurements were made in a sub-resonant forced pendulum (0.1–20 Hz) and in a vibrating reed equipment (kHz range). A stable (P1) peak has been detected at 410 K (1 Hz), with a corresponding modulus step. The appearance of this relaxation peak in the Pr_1/2Ca_1/2MnO₃ compound, and its high activation energy value, similar to the other compounds measured, indicates that the microscopic origin of this relaxation does not correspond to an oxygen jump (characteristic activation energy0.8–0.9 eV).     

也谈伏安法测电阻时电流表内、外接法的判定条件

给出了一种在物理实验中用伏安法测电阻时电流表采用内、外接法的判定条件.     

伏安法测电阻时安培表采用内、外接法的判定条件

导出了在物理实验中用伏安法测电阻时安培表采用内、外接法的判定条件,并在实验上给予了验证．     

Density and binding energy of α1 and α3 electrons inside electron-hole droplets

We have measured the density and binding energy of α₁ and α₃ electrons inside electron-hole droplets in germanium stressed from 6 to 9 kg/mm² in the 〈111〉 direction. The decrease in density with increasing stress is due to narrowing of the valence band. The difference in the binding energies of α₁ and α₃ electrons is from their different average kinetic energies.     

Colossal room-temperature magnetoresistance of La1/3Nd1/3Sr1/3MnO3 single crystals

Replacement of one half of the neodymium ions by lanthanum in Nd_2/3Sr_1/3MnO₃ is shown to result in a considerable increase in the Curie temperature. The single-crystal La_1/3Nd_1/3Sr_1/3MnO₃, whose Curie point lies at 315 K, has been found to exhibit a record-high magnetoresistance of 27% in a weak magnetic field of 8.4 kOe in the temperature range above room temperature.     

Faddeev πNN dynamics with ρ-exchange contribution for the 1D2 and 3F3 diproton anomalies

The ¹D₂ and ³F₃ diproton anomalies are studied in a framework of Faddeev πNN dynamics with ρ-exchange contribution. Two-body interactions in πN-P₃₃, πN-P₁₁, NN-³P₂; and NN-³Si₁ states are input. The pp-pp, pp-πd and πd-πd processes are treated in a unified way and the results are compared with partial wave analysis results of each process. The ¹D₂ and ³F₃ diproton anomalies are qualitatively explained by the present models. The ρ-contributions are remarkable in the amplitudes of pp-pp and pp-πd processes from the pp-¹D₂ state.     

Instanton contribution for the CP1 model: Spherical and periodic boundary conditions

The instanton contribution for the CP₁ model with periodic boundary conditions is interpreted as the partition function of a neutral Coulomb gas in a finite volume.     

E-T phase diagrams of a solid solution of the multicomponent PbZn1/3Nb2/3O3-PbMg1/3Nb2/3O3-PbNi1/3Nb2/3O3-PbTiO3 system near the morphotropic phase boundary

The specific features of the dielectric and pyroelectric responses of a solid solution in the barium-doped multicomponent yPbZn_1/3Nb_2/3O₃-mPbMg_1/3Nb_2/3O₃-nPbNi_1/3Nb_2/3O₃-xPbTiO₃ system of the composition y = 0.0982, m = 0.4541, n = 0.1477, and x = 0.3 near the morphotropic phase boundary have been investigated. It has been assumed that the maxima revealed in the dependences of the reversible permittivity on the electric field strength with both the forward and backward changes in the field (E ₌) are associated with the induced phase transition. Based on the experimental results, the E-T phase diagrams are constructed in the temperature range from ?100 to 150°C for different temperature-field regimes: (i) variation in the electric field E ₌ at a fixed temperature of the sample and (ii) variation in the temperature of the sample at a constant value of E ₌. It has been found that there is a singular point in the E-T phase diagram and that, in the vicinity of this point, the dielectric and pyroelectric responses of the studied ceramics exhibit specific features.