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931.
Gerald D Fong Robert L Kuczkowski Arthur J Ashe 《Journal of Molecular Spectroscopy》1978,70(2):197-208
The microwave spectrum of 121-SbC5H5, 123-SbC5H5, β-dideutero 121-SbC5H3D2 and 123-SbC5H3D2 has been assigned in the region 26.5–40.0 GHz. The respective rotational constants and uncertainties are: A = 4512.69 ± 0.42, B = 1738.00 ± 0.01, C = 1254.51 ± 0.01; A = 4512.84 ± 0.30, B = 1729.80 ± 0.01, C = 1250.22 ± 0.01; A = 4176.18 ± 0.33, B = 1660.94 ± 0.01, C = 1188.15 ± 0.01; A = 4176.60 ± 0.61, B = 1652.94 ± 0.03, C = 1184.03 ± 0.03 (in MHz units). The structure is found to be planar, C2v in symmetry. The and ∠CSbC = 92.9° ± 1.0°. The nuclear quadrupole coupling constants for the 121 and 123 antimony isotopes are χaa = 456.4 ± 4.1 MHz, η = 0.396 ± 0.008, and χaa = 583.00 ± 5.3 MHz, η = 0.399 ± 0.008, respectively. Several alternate techniques using the coupling constants as data support a σ-donating property for antimony. 相似文献
932.
It is shown that a cost function subject to internal costs of adjustment induces a stochastic discount factor (pricing kernel)
that is a function of random output, input and output prices, existing capital stock, and investment. The only assumption
on firm preferences is that they are increasing in current period consumption and future stochastic consumption. This ensures
that the firm will always act to minimize current period cost of providing future consumption, and it is the first-order conditions
for this cost minimization problem that generate the stochastic discount factor, which itself can be interpreted as the marginal
variable cost of varying stochastic output. A cost-based pricing kernel is estimated using annual time-series data on macroeconomic
variables and returns data for the S&P 500 and commercial paper. 相似文献
933.
Robert Hable 《International Journal of Approximate Reasoning》2010,51(9):1114-1128
The article considers estimating a parameter θ in an imprecise probability model which consists of coherent upper previsions . After the definition of a minimum distance estimator in this setup and a summarization of its main properties, the focus lies on applications. It is shown that approximate minimum distances on the discretized sample space can be calculated by linear programming. After a discussion of some computational aspects, the estimator is applied in a simulation study consisting of two different models. Finally, the estimator is applied on a real data set in a linear regression model. 相似文献
934.
We consider a risk minimization problem in a continuous-time Markovian regime-switching financial model modulated by a continuous-time,
observable and finite-state Markov chain whose states represent different market regimes. We adopt a particular form of convex
risk measure, which includes the entropic risk measure as a particular case, as a measure of risk. The risk-minimization problem
is formulated as a Markovian regime-switching version of a two-player, zero-sum stochastic differential game. One important
feature of our model is to allow the flexibility of controlling both the diffusion process representing the financial risk
and the Markov chain representing macro-economic risk. This is novel and interesting from both the perspectives of stochastic
differential game and stochastic control. A verification theorem for the Hamilton-Jacobi-Bellman (HJB) solution of the game
is provided and some particular cases are discussed. 相似文献
935.
In this paper we give irrationality results for numbers of the form where the numbers an behave like a geometric progression for a while. The method is elementary, not using differentiation or integration. In particular, we derive elementary proofs of the irrationality of π and em for Gaussian integers m≠0. 相似文献
936.
Robert Y. Levine 《Foundations of Physics Letters》1993,6(2):119-137
The simultaneous measurement of Dirac field operators is formulated in analogy to the work of von Neumann and Arthurs-Kelly. Meter fields are coupled to the system field with a relativistically invariant bilinear interaction. Measurement of vacuum meter field expectation values provides for the simultaneous measurement of noncommuting system components. It is shown that two meter coupling allows for a simultaneous minimum in the variance of the subsequent meter measurements. A pseudoscalar self-interaction of the Dirac field is shown to allow simultaneous measurement of positive energy field operators with negative energy meters. The simultaneous measurement ofn noncommuting field operators is obtained by coupling the system ton fermionic fields. Also, in this paper the related concept of mutual simultaneous measurement is developed. This requires that any operators in the enlarged Hilbert space are measurable by the remaining fields as meters. System embedding into a larger Hilbert space results in added noise due to the zero point motion of the meter fields. By the negentropy principle of Brillouin, the added noise is equivalent to entropy. A criterion determining the interaction among fields is that the averaged added noise in the components of each quantum field is minimized. This criterion defines an optimum fermionic mass matrix through the determination of the entangling interaction.1. This work was sponsored by the Department of the Air Force under contract F19628-90-C-0002. 相似文献
937.
We consider Brownian motion in the presence of an external and a weakly coupled pair interaction potential and show that its stationary measure is a Gibbs measure. Uniqueness of the Gibbs measure for two cases is shown. Also the typical path behaviour, the degree of mixing and some further properties are derived. We use cluster expansion in the small coupling parameter. 相似文献
938.
Robert S. Van Dyck Jr. Steven L. Zafonte Paul B. Schwinberg 《Hyperfine Interactions》2001,132(1-4):163-175
Based on the use of a single ion, isolated at the center of a cryogenically cooled Penning trap, an environment is produced
which makes this mass spectrometer remarkably free of systematic errors. The most notable developments in our quest for an
ultra-high accuracy instrument were (a) the compensation of the trapping potential, (b) the discovery that motional sidebands
could manipulate radial energies, (c) the use of multiply-charged ions that could improve signal-to-noise, and (d) the use
of an ultra-stable superconducting magnet/cryostat system with drift <0.010 ppb/h. The dominant systematic errors are associated
with radial electric fields caused by image charges in the trap electrodes and with the rf-electrical drive field used to
determine the harmonic axial resonance. To illustrate the potential of this improved spectrometer, the four-fold improved
measurement of the proton's mass and the eight-fold improved measurement of oxygen's atomic mass will be described.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
939.
Viviane M. Oliveira Barrichelo Reinhardt J. Heuer Carole M. Dean Robert T. Sataloff 《Journal of voice》2001,15(3):344-350
Many studies have described and analyzed the singer's formant. A similar phenomenon produced by trained speakers led some authors to examine the speaker's ring. If we consider these phenomena as resonance effects associated with vocal tract adjustments and training, can we hypothesize that trained singers can carry over their singing formant ability into speech, also obtaining a speaker's ring? Can we find similar differences for energy distribution in continuous speech? Forty classically trained singers and forty untrained normal speakers performed an all-voiced reading task and produced a sample of a sustained spoken vowel /a/. The singers were also requested to perform a sustained sung vowel /a/ at a comfortable pitch. The reading was analyzed by the long-term average spectrum (LTAS) method. The sustained vowels were analyzed through power spectrum analysis. The data suggest that singers show more energy concentration in the singer's formant/speaker's ring region in both sung and spoken vowels. The singers' spoken vowel energy in the speaker's ring area was found to be significantly larger than that of the untrained speakers. The LTAS showed similar findings suggesting that those differences also occur in continuous speech. This finding supports the value of further research on the effect of singing training on the resonance of the speaking voice. 相似文献
940.
Under mild additional assumptions this paper constructs quasi-interpolants in the form
with approximation order ℓ−1, whereh(x) is a linear combination of translatesψ(x−jh) of a functionψinCℓ(
). Thus the order of convergence of such operators can be pushed up to a limit that only depends on the smoothness of the functionψ. This approach can be generalized to the multivariate setting by using discrete convolutions with tensor products of odd-degreeB-splines. 相似文献
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