共查询到20条相似文献,搜索用时 31 毫秒
1.
Strengths are calculated for the fundamental vibration-rotation bands of ozone in the infrared adopting a variational method of vibration-rotation analysis. These calculations make use of available ab initio electronic theory to assign algebraic signs for the coefficients in the dipole moment expansion to internal coordinates. Magnitudes of these coefficients are chosen so that they are consistent with available vibrational intensity data. 相似文献
2.
SUMMARY: Upper respiratory tract infections (URIs) are a major cause of morbidity among vocal arts professionals, both from their acute impairment of the vocal mechanism and their predisposing influence for the development of serious vocal sequelae. In this review, we present some of the salient features of currently available treatments effective against influenza, the virus family responsible for the most serious form of URI. At present, these include an inactivated vaccine and four antiviral drugs, each approved in the United States and many other countries for the prevention and treatment of influenza. A live attenuated vaccine is also available, and other vaccines and antiviral drugs are under development. This review details the current options available for treating both influenza and noninfluenza related URIs in the professional voice user. 相似文献
3.
W.A. Utley 《Applied Acoustics》1980,13(2):85-102
The principal sources of noise in opencast coal mining operations are described. Currently available information on the assessment, prediction, measurement and control of this type of noise is considered. Some of the problems associated with the setting up of a scheme for the control of noise from opencast sites which are discussed are found to apply to other sources of environmental noise. It is concluded that at present there is insufficient information available to enable a scheme covering all aspects of noise control to be produced. Suggestions are made for further research. 相似文献
4.
Calculation for electron impact total ionization cross sections on halogen compounds (BF, SiF, BCl, SiCl) are performed employing
Spherical Complex Optical Potential and Complex Optical Potential — ionization contribution (CSP-ic) formalisms. In this article
we are presenting data for energies ranging from above threshold to 2000 eV. Our results are compared with available experimental
and theoretical data wherever available. It is found that the present result gives a better account of the ionization cross
sections. 相似文献
5.
6.
W. Cook C. Mounfield P. Ormerod L. Smith 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,27(2):189-195
Property is an asset which forms part of the portfolios of many investors, particularly institutional ones, along with equities
and bonds. Techniques from physics, particularly that of random matrix theory, have provided powerful insights into the behaviour
of financial assets. A large database providing time series data for over 10,000 individual properties is available for the
UK. Some of the data is available at an annual and some at a monthly frequency. However, even at the monthly frequency, only
a relatively small number of observations is available, certainly in comparison with that available with financial assets.
A key issue in translating methods of analysis in financial markets to property data is whether they are applicable given
the small number of data points available. This paper addresses this issue. Using the tools of random matrix theory, we find
that a great deal of information is contained within property data. The correlations between different types and geographical
locations of property tend to have far more true information and be more stable over time than is the case with financial
data, despite the large number of observations available with the latter.
Received 31 December 2001 相似文献
7.
基于DPDV算法的二元光学元件设计 总被引:1,自引:0,他引:1
为解决用于高斯分布激光束整形的二元光学元件设计问题 ,在深入研究现有的各种迭代算法 ,如GS算法、模拟退火法、Alopex法等的基础上 ,提出了并行模拟退火算法和DPDV算法 (DifferentParametertoDifferentVariables)。特别是DPDV算法综合了各种算法的优点 ,而避开了其缺点。得到了迄今为止最好的计算结果 相似文献
8.
基于电介质复折射率的实验数据,采用最小二乘法结合选取的代表频率拟合得到了电介质的介电谱解析表达式,可以得到电介质在全频段的光频常数和介电常数. 研究了三个典型液态电介质,水、乙醇和甲苯的介电谱. 在实验数据可以获取的频率范围内,采用解析表达式得到的光频常数与采用Kramers-Kronig转换得到的折射率实部和实验得到的折射率虚部吻合得很好. 基于介电谱解析表达式可以预测目前实验无法测量的区域的介电谱. 相似文献
9.
In practice, decrypting a random-phase encrypted volume holographic data storage system is impossible unless the original random-phase plate for the encryption is available. However, this study demonstrates that under certain conditions, ways are available that can decrypt an encrypted photorefractive LiNbO3 crystal holographic storage system. In addition to presenting experimental results that show the efficacy of this decryption approach, problems and difficulties in the experiments are discussed. 相似文献
10.
The numerical simulation of radiative heat transfer is now well established. Key ingredients in such a simulation model are calculated view factors that are used to describe the exchange of radiated energy between different surfaces. Several methods for the calculation of these geometrical factors are available, including Integration, Monte Carlo, and the Hemi-cube methods. Several analytical test cases are also available, such as the well-known “parallel plates” case, which allow modelers to validate their view factor routines. However, there is much less information available that combines both view factor information and heat transfer effects simultaneously. This article describes the construction of a simple testing rig that allows experiments to be performed that combine view factor effects with measured heat transfer exchanged between surfaces only. The equipment has been used to consider simple cases, such as the parallel plates test case, and also cases where shadowing is important. The results of these experiments are presented as experimental benchmarking data for model users and developers. 相似文献
11.
Waters KR Hughes MS Mobley J Brandenburger GH Miller JG 《The Journal of the Acoustical Society of America》2000,108(2):556-563
In the recent literature concern has been raised regarding the validity of Kramers-Kronig relations for media with ultrasonic attenuation obeying a frequency power law. It is demonstrated, however, that the Kramers-Kronig dispersion relations for application to these types of media are available. The developed dispersion relations are compared with measurements on several liquids, and agreement is found to better than 1 m/s over the experimentally available bandwidth. A discussion regarding the validity of these dispersion relations, in particular how the dispersion relations relate to the so-called Paley-Wiener conditions, forms the conclusion. 相似文献
12.
H.L. Xu P. Quinet P. Palmeri 《Journal of Quantitative Spectroscopy & Radiative Transfer》2007,104(1):52-70
From a combination of radiative lifetime measurements, performed with a time-resolved laser-induced fluorescence technique, for nine odd-parity levels of Ir I and four odd-parity levels of Ir II and branching fraction calculations, extended sets of transition probabilities have been derived for transitions of astrophysical interest. The new results are compared with the few experimental data available in the literature and a good agreement is found. They extend considerably the previous sets of transition probabilities available in the literature. Implications of the new results regarding the solar content of iridium are briefly discussed. 相似文献
13.
As aircraft systems become more complicated it is necessary to display information which was either not previously available or was provided by instruments which were unduly bulky, heavy, expensive, or unreliable. This paper considers possible display mechanisms for future cockpits and their performance in high ambient illumination. Methods of optimizing the legibility of commercially available display types using contrast enhancement techniques are described. Finally the results of subjective tests on light emitting diode displays are discussed. 相似文献
14.
K. Hasegawa 《The European Physical Journal C - Particles and Fields》2010,70(1-2):285-293
The publicly available package for an automated dipole subtraction, AutoDipole, is extended to include the SUSY dipoles in the MSSM. All fields in the SM and the MSSM are available. The code is checked against the analytical expressions for a simple process. The extended package makes it possible to compute the QCD NLO corrections to SUSY multi-parton processes like the stop pair production plus jets at the LHC. 相似文献
15.
Multi-reference configuration interaction is used to produce potential energy curves(PECs) for the excited B1Π state of KH molecule.To investigate the correlation effect of core-valence electrons,five schemes are employed which include the different correlated electrons and different active spaces.The PECs are fitted into analytical potential energy functions(APEFs).The spectroscopic parameters,ro-vibrational levels,and transition frequencies are determined based on the APEFs and compared with available experimental and theoretical data.The molecular properties for B1Π obtained in this letter,which are better than those available in literature,can be reproduced with calculations using the suitable correlated electrons and active space of orbitals. 相似文献
16.
Electron scattering cross sections from DNA/RNA bases are calculated in the 10 eV–10 keV energy range by combining screening-corrected aditivity-rule (SCAR) with ab-initio quasifree inelastic atomic potential. Similar calculations compare very favourably with available experimental data for benzene, C6F6 and tetrahydrofuran molecules. For DNA/RNA bases, where no experimental data is available, present results are compared with other theoretical values. 相似文献
17.
Gülen Ferah Kemal Colakoglu Yasemin Oztekin Ciftci Soner Ozgen Sefa Kazanc 《Central European Journal of Physics》2007,5(2):207-220
In this study, molecular dynamics simulations are performed by using a modified form of Morse potential function in the framework
of the Embedded Atom Method (EAM). Temperature-and pressure-dependent behaviours of bulk modulus, second-order elastic constants
(SOEC), and the linear-thermal expansion coefficient is calculated and compared with the available experimental data. The
melting temperature is estimated from 3 different plots. The obtained results are in agreement with the available experimental
findings for iridium.
相似文献
18.
There are many methods available to synthesize nanomaterials and the glow discharge plasma electrolysis is a novel and a green
method in this category. It is seen that most of the papers are published after 2005 and the interest in it is growing due
to its applicability in the industry for preparing nanomaterials at large scale. But, only few results are available yet and
most of them are on metal nanoparticle preparation, so that more studies are needed to understand the nature of growth of
the nanoparticles under glow discharge in liquid and its applicability in preparing semi-conductor nanomaterials. Many have
tried many methods to prepare nanoparticles by the glow discharge and a review like this is the need of the time to understand
its present status that helps to modify the present situation to a better one. This review classifies all the available methods
of nanomaterials synthesis in liquid by glow discharge in to three and it is discussed in detail. 相似文献
19.
The scaling of the number, the mean-squared end-to-end distance, and the mean displacement in the direction of the first step, for semiflexible chains on the square, triangular and simple cubic lattices are investigated by enumerating self-avoiding walks classified according to the number of turns. Simple scaling forms are found to describe adequately all the available data. Estimates of the scaling functions are obtained and compared with the Gaussian results, when available. Self-avoidance effects are suppressed but do not vanish identically ind=3, contrary to recent theoretical expectations. 相似文献
20.
David Lichtman 《Surface science》1983,131(1):159-166
A pseudo-first principles technique for Auger quantitation was used to calculate relative Auger yields. These yields were compared to the experimental sensitivity factors found in the Handbook of Auger Electron Spectroscopy. In cases where pure element standards are readily available, theory agreed quite well with experiment 95% of the time. However, when pure element standards are not available, such as the lanthanide series and the light elements from Z = 7 to 12, large deviations exist. Plots of the calculated yields for 3, 5 and 10 kV primary beams are superimposed upon the Handbook sensitivity factor graphs and the reasons for the similarities and differences are discussed. 相似文献