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1.
The character of a sound is defined as the weighted combination of all acoustic factors, not contained in LA, contributing to its annoyance.From this definition it follows that differences in annoyance due to sounds with equal LA are differences in sound character. For the concept of sound character to have real significance it is necessary that listeners agree on the annoyance due to sounds with equal LA.This paper describes a listening experiment with a variety of sounds of equal LA. The annoyance due to the sounds was rated by twelve subjects. Their individual ratings show significant agreement. Moreover, their average rating correlates well (0·90) with the ratings obtained by Terhardt and Stoll in a similar experiment.  相似文献   

2.
Summary We report on the analysis of 18 months of data of the GEOGRAV experiment: a room temperature gravitational-wave antenna equipped with various sensors of geophysical quantities (accelerometer, gravimeter and electrical antenna). We present results on the search for sidereal periodicities in the background of the gravitational-wave antenna as regards both hourly averages and large-amplitude pulses.
Riassunto Si riferisce sull'analisi di 18 mesi di dati dell'esperimento GEOGRAV: un'antenna gravitazionale a temperatura ambiente equipaggiata con sensori di grandezze geofisiche (accelerometro, gravimetro ed antenna elettrica). Si presentano risultati sulla ricerca di periodicità siderali nel fondo dell'antenna gravitazionale, per quanto riguarda sia le medie orarie che gli impulsi di grande ampiezza.

Резюме Мы анализируем данные, полученные в течение 18 месяцев в эксперименте ?GEOGRAV?: антенна гравитационных волн при комнатной температуре, снабженная различными датчиками геофизическин величин (акселерометр, гравиметр и электрическая антенна). Приводятся результаты по поиску сидерических периодичностей в фоне антенны гравитационных волн.
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3.
 For aL (ℝ+)∩L 1 (ℝ+) the truncated Bessel operator B τ (a) is the integral operator acting on L 2 [0,τ] with the kernel
where J ν stands for the Bessel function with ν>−1. In this paper we determine the asymptotics of the determinant det(I+B τ (a)) as τ→∞ for sufficiently smooth functions a for which a(x)≠1 for all x[0,∞). The asymptotic formula is of the form det(I+B τ (a))∼G τ E with certain constants G and E, and thus similar to the well-known Szeg?-Akhiezer-Kac formula for truncated Wiener-Hopf determinants. Received: 23 April 2002 / Accepted: 25 September 2002 Published online: 24 January 2003 RID="*" ID="*" Supported in part by NSF Grant DMS-9970879. Communicated by J.L. Lebowitz  相似文献   

4.
The blinking of quantum dots under the action of laser radiation is described based on a model of a binary (two-state) renewal process with on (fluorescent) and off (non fluorescent) states. The T on and T off sojourn times in the on and off states are random and power-law distributed with exponents 0 < α < 1 and 0 < β < 1; the averages of the on and off times are infinite. As a consequence of this, the Gaussian statistics is inapplicable and the process is described using a more general statistics. An equation for the density of distribution p(t on|t) of the total on time during the observation time t is derived that contains derivatives of fractional orders α and β. A solution to this equation is found in terms of fractional stable distributions. The Poisson transform of the density p(t on|t) leads to the photon counting distribution and determines the fluorescence statistics. It is demonstrated that, if a blinking process with exponents α < β is implemented, then, at fairly long times, the on time will considerably prevail over the off time, i.e., blinking will be suppressed. This behavior is evidenced by the types of distributions of the total fluorescence time, the decay of relative fluctuations, and the Monte Carlo simulated trajectories of the process.  相似文献   

5.
段永华  孙勇  何建洪  彭明军  郭中正 《物理学报》2012,61(4):46101-046101
为了了解Pb-Mg-Al合金腐蚀的物理本质, 本文采用基于第一性原理的赝势平面波方法系统地计算了Pb-Mg-Al合金中各物相的结合能、费米能级和局域态密度等电子结构参数, 分析了合金的电化学腐蚀机理. 计算结果表明:Pb-Mg-Al合金中各主要组成物相稳定性大小关系为 Mg17Al12>Mg2Pb>Mg;Mg,Mg2Pb和Mg17Al12的费米能级存在Ef(Mg)>Ef(Mg2Pb)>Ef(Mg17Al12)的关系, 说明Mg最容易失去电子, Mg2Pb次之, Mg17Al12最难;局域态密度表明, 在同样的外界条件下, 体系中Mg相和Mg2Pb相对于Mg17Al12均处于不稳定的状态, 容易失去电子, 即容易发生腐蚀. Pb-Mg-Al合金体系中不同物相的费米能级差构成了电化学腐蚀的电动势, 导致电子从费米能级高的Mg相和Mg2Pb相流向费米能级低的Mg17Al12相, 使Pb-Mg-Al合金发生腐蚀.  相似文献   

6.
M. F. Sarry 《Technical Physics》1998,43(10):1137-1144
A universal derivation of the thermodynamic equations on the basis of a combined analysis of the exact relations for any material — the virial theorem, the shock adiabat, and the differential thermodynamic identity relating the thermic and caloric equations of state of matter — is given. This combination makes it possible to reduce the fundamental problem of thermodynamics to a boundary-value problem of mathematical physics. Analytic relations T s=T(P s,ρ s and T s=T(D,u) are obtained for classical systems. Zh. Tekh. Fiz. 68, 1–9 (October 1998)  相似文献   

7.
8.
9.
Relativistic quantum calculations which include spin-orbit interactions and correlations were carried out for the low-lying states of ICl. Spectroscopic properties (R3, ωe, Te) were calculated for these states. Based on the energies and wave functions both the absorption and emission spectra of ICl in the region below 45000 cm−1 were interpreted. These calculations confirm the predissociation of the B0+ state and the existence of a second minimum (B′0+) in the 0+(II) state. Properties of the 0(I)(3Π0) state which is yet to be observed were also predicted. The calculated properties for the 2(I)(3Π2) state are in very good agreement with the properties obtained by the very recent characterization of the A′ state by optical three-photon resonance. The continuous and diffuse absorption spectra of ICl in the region below 45000 cm−1 were interpreted and assigned to the appropriate electronic transitions.  相似文献   

10.
A formula at low temperature for the function G(1λ) = Iλλ6 has been derived in terms of configuration curve theory and checked on luminescence spectra near 77 K. The vibrational quantum in the excited state has been calculated from the decrease of G(1λM), where λM is the wavelength of the maxima of G at low temperature, as a function of temperature.  相似文献   

11.
12.
Ab initio molecular orbital studies on C2H6 + support an assignment of 2 A 1g (D 3d point group symmetry) for the ground state of this cation. This differs from the prediction of Koopmans' theorem which suggests a 2 Eg state for vertical ionization. Approximate force constants and vibrational frequencies are calculated for the ethane cation in the 2 A 1g state and are found to be consistent with the vibrational progression observed in the experimental photoelectron spectrum.  相似文献   

13.
A method of classification of many-electron states that involves symmetry groups of four-dimensional space is developed. Taking into account the spatial and temporal symmetry, the selection rules for electric and magnetic dipole transitions are investigated. The reduction relations for the irreducible representations of the orthogonal group O 4 and the group R 4 of pure rotations of the four-dimensional space on the groups and O h 4 and O 4 of the four-dimensional cube and of the octahedron on the three-dimensional groups O h and D 6h of the cubic and hexagonal systems, respectively, are obtained. The four-dimensional classification of the levels of the spin-orbit interaction of rare earth ions for the intermediate reduction on the group of the four-dimensional cube is performed. With the help of the irreducible representations of the O 4 group, the selection rules of magnetic and forbidden electric dipole transitions, as well as of intercombination transitions, are investigated.  相似文献   

14.
15.
We consider fluctuations of the solution W ε (t, x, k) of the Wigner equation which describes energy evolution of a solution of the Schrödinger equation with a random white noise in time potential. The expectation of W ε (t, x, k) converges as ε → 0 to \({\bar{W}(t,x,k)}\) which satisfies the radiative transport equation. We prove that when the initial data is singular in the x variable, that is, W ε (0, x, k) = δ(x)f(k) and \({f\in {\mathcal{S}}(\mathbb{R}^d)}\), then the laws of the rescaled fluctuation \({Z_\varepsilon(t):=\varepsilon^{-1/2}[W_\varepsilon(t,x,k)-\bar{W}(t,x,k)]}\) converge, as ε → 0+, to the solution of the same radiative transport equation but with a random initial data. This complements the result of [6], where the limit of the covariance function has been considered.  相似文献   

16.
Filtering states on orthomodular lattices have been introduced by G.T. Rüttimann as an “opposite” of completely additive states. He proved that they form a face of the state space. The question which faces can be the sets of filtering states remained open. Here we prove that, for any semi-exposed face F of a compact convex set C, there is an orthomodular lattice L and an affine homeomorphism φ of C onto the state space of L such that φ(F) is the space of filtering states.  相似文献   

17.
A metric defined by ds2 = [(p2 + q2)P] dp2 + [P(p2 + q2)](dτ + q2 dσ)2 + [(p2+q2)Q] dq2 ? [Q(p2 + q2)](dτ ? p2 dσ)2, with P = P(p), Q = Q(q), is studied; the first sections investigate its connections and curvature; the metric is of type D, with Einstein tensor of the electromagnetic algebraic type. Metrics with R = const are characterized by P and Q being polynomials of 4th order. In Section 5, by applying Rainich-Wheeler procedure, the electromagnetic field associated with the studied metric is constructed. Section 6 describes change-of-scale transformations of the derived solution of Einstein-Maxwell equations with λ; Sections 7 and 8 study geodesics and trajectories of charged test particles in the field of this solution; with H-J equation separable, the integration process reduces to quadratures. Section 9 gives a summary of basic results, Sections 10 and 11 investigate contractions of general solution with 6 continuous and 1 discrete parameter to the generalized NUT, anti-NUT and Bertotti-Robinson solutions. Section 12 specializes our general solution to the combined NUT and Kerr-Newman solution. Section 13 investigates a complex extension and the double Kerr-Schild form of our solution of Einstein-Maxwell equations with λ. Finally, Section 14 investigates the special-relativistic limit of the discussed solutions: a construction of a topology of flat space-time is proposed in such a manner, that in a sense it represents a “riemannian sheet” of the analytic structure of the electromagnetic field of the Kerr-Newman solution. Concluding remarks which indicate a further generalization of the present results, derived together with Demiañski, close this paper.  相似文献   

18.
Self-broadened, air-broadened and CO2-broadened half-widths of lines R(0) through R(0) in the CO fundamental have been measured at 100°K (self-broadening only), 200°K, 250°K and 300°K using the Ladenburg-Reiche curve-of-growth. The relation γ°m(T)γ°m(300°K)=(300T)0.75, which we found previously for the nitrogen-broadened half-widths of R(0), R(8) and R(16), is shown to be valid for all of the line widths measured in the present study.  相似文献   

19.
This report is a continuation of an analysis, initiated elsewhere V.V. Vecheslavov and B. V. Chirikov, Zh. éksp. Teor. Fiz. 114, 1516 (1998) [JETP 86, 823 (1998)], of the effect of splitting of the separatrix of a nonlinear resonance for the model of standard mapping, based on results of direct measurements of the splitting angle α(K), where K is the system parameter. Measurements were made in the previously used wide range 0.1≳α≳10−208 (1⩾K⩾0.0004), but with significantly higher relative (better than 1050) and average (∼10−55) accuracy. This procedure made it possible to substantially refine the effects observed in Ref. 1 and construct qualitatively new empirical dependences providing reliable extrapolation of the data obtained for the angle and the invariant in the intermediate asymptotic limit K≲10−2 beyond the limits of the investigated region. The results obtained by us can be useful for further development of the theory of separatrix splitting and formation of the stochastic layer of a nonlinear resonance. Zh. éksp. Teor. Fiz. 116, 336–346 (July 1999)  相似文献   

20.
XPS with variable take-off angle has been applied to the determination of the thickness of thin oxide layers (SiO2 on Si). The information about Dox gained by such measurements is strongly influenced by surface roughness. This influence can be demonstrated when the parameters R and D/λox are calculated from sets of the experimental results and for each set the corresponding pair of R and Dox is plotted in a diagram Dox = f(R). Having the true value of R it is possible to determine Dox. With the XPS-results of at least three different oxide layers and their ellipsometric thicknesses De one is able to calculate λSi, λoxSi and the difference ΔD between De and the XPS-thickness D.  相似文献   

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