热物理激光测量中的三维温度场重构方法

针对热物理激光测量中的三维温度场重构问题，进行了几种算法的讨论．对双高斯函数形式的温度分布进行了重构计算，对重构算法进行了检验，对实验过程中可能出现的误差进行了模拟，讨论了它们对重构结果的影响．     

基于MATLAB的RC串联电路暂态过程仿真

对RC串联电路暂态过程进行了研究,并对其进行了理论分析,最后利用MATLAB的绘图功能,对实验现象进行了仿真,仿真结果与实验相符.     

向列相液晶中空间光孤子的研究进展

对向列相液晶中空间光孤子产生机制进行了详细的阐述，并对其目前的研究进展进行了概括介绍。最后，对它们的应用前景进行了展望。     

X波段盘圆加速结构（DAW）优化设计

介绍了X波段DAW加速结构的优化过程,给出了利用SUPERFISH程序进行腔形优化的数学模型以及利用该模型对X波DAW结构的优化设计结果,给出了利用MAFLA400程序对加支撑杆的DAW结构进行优化设计的结果,讨论了支撑杆对DAW结构微波特性的影响,同时,对DAW加速结构有无支撑杆的色散曲线分别进行了计算,对Washer支撑杆对DAW加速结构色散特性的影响进行了讨论。     

X波段盘圈加速结构(DAW)优化设计

介绍了X波段DAW加速结构的优化过程.给出了利用SUPERFISH程序进行腔形优化的数学模型以及利用该模型对X波段DAW结构的优化设计结果.给出了利用MAFIA400程序对加支撑杆的DAW结构进行优化设计的结果,讨论了支撑杆对DAW结构微波特性的影响.同时,对DAW加速结构有无支撑杆的色散曲线分别进行了计算,对Washer支撑杆对DAW加速结构色散特性的影响进行了讨论.     

红敏重铬酸盐明胶增感的新方法

对普通红外敏明胶感光度低的原因进行了分析。在此基础上提出了多敏感中心的新增感方法。文中对这种方法的增感机理从光化学角度进行了分析，并用红外光谱和对比实验进行了验证。最后还对这种增感方法的实际效果进行了考察。     

超声清洗槽内空化强度的测量

对洗涤槽内超声空化的相对强度及其分布进行了研究。采用铝箔腐蚀法,应用图像、数据处理软件对试验结果进行处理,最后对实验结果进行了讨论。     

对物理学几组著名公式的哲学思考

对几个著名物理公式进行了剖析,对其哲学涵义进行了阐述,并分析了它们对物理学思想方法的影响.     

银溶胶SERS光谱在分析方面的应用研究

本文利用乙醇作为内标对结晶紫进行了定量分析,对最佳溶胶粒度进行了选择,并使结晶紫的检测限降至5×10~(-12)mol/l,实验中还对 KCl、乙醇等对溶胶粒度的影响进行了研究,并讨论了溶剂极性对 SERS 谱带频率的影响。通过1620cm~(-1)苯环伸缩振动频率的位移现象对结晶紫的吸附取向进行了初步探讨。     

平面激光诱导荧光技术在交错电极介质阻挡放电等离子体研究中的初步应用

利用平面激光诱导荧光技术对交错电极介质阻挡放电过程中产生的痕量组分NO进行了检测. 通过数值模拟对实验结果进行了分析说明,并对介质阻挡放电等离子体流动控制原理进行了简要分析. 此外还通过平面激光诱导荧光技术对等离子体诱导流动进行了直观显示. 关键词： 平面激光诱导荧光 等离子体 介质阻挡放电     

Factors influencing the sound preference in urban open spaces

In this paper, based on a large scale survey in Europe and China as well as corresponding laboratory studies, the influencing factors on the sound preference evaluation, considering social, demographical, physical, behavioural and psychological facets, have been systematically examined based on statistical analyses for each of the 19 case study sites. Various sound types have been considered, including natural, human, mechanical and instrumental sounds. In terms of social/demographical factors, the results suggest that age and education level are two factors which universally influence the sound preference significantly, although the influence may vary with different types of urban open spaces and sounds. With increasing age or education level, people tend to prefer natural sounds and are more annoyed by mechanical sounds in general. It has also been found that gender, occupation and residence status generally would not influence the sound preference evaluation significantly, although gender has a rather strong influence for certain sound types such as bird sounds, especially at certain case study sites. In terms of physical factors (season, time of day), behavioural factors (frequency of coming to the site, reason for coming to the site), and psychological factors (site preference), generally speaking, their influence on the sound preference evaluation is insignificant, except for limited case study sites and certain sound types. The influence of home sound environment, in terms of sounds heard at home, on the sound preference has been found to be generally insignificant, except for certain sounds. It is noted that there are some correlations between social/demographical factors and the studied physical/behavioural/psychological factors, which should be taken into account when considering the influence of individual factors on sound preference.     

波叠加法在结构辐射声功率计算中的应用

描述了用波叠加法来计算任意形状辐射体的辐射声功率的方法。该方法在给定辐射体表面的振动速度后就可求解辐射源的强度,进而求解辐射体表面声功率。文中以脉动球源的辐射问题为列,讨论了波叠加法在应用过程中对单元、节点数目以及单元形状的敏感性。通过将该方法计算结果与解析结果进行对比表明,运用此方法在保证较高精度的前提下能明显减少计算所需的单元节点数,从而节省时间提高计算效率。     

A model comparison of the absorption coefficient of a Microperforated Insertion Unit in the frequency and time domains

The absorption coefficient of acoustic materials can be measured either in the frequency or the time domain. At normal incidence, a sample of the material is fitted within an impedance tube and the absorption coefficient is calculated in the frequency domain from the measurement of the transfer function between two microphones [ISO 10534-2. Acoustics - determination of sound absorption coefficient and impedance in impedance tubes - Part 2: transfer function method. ISO, Geneva, Switzerland; 1996]. When the acoustic material must be characterized at oblique incidence or in situ (noise barriers, for instance) the absorption coefficient is calculated from measurements of the loudspeaker-microphone impulse response in the time domain, both in free field and in front of the sample [CEN/TS 1793-5. Road traffic noise reduction devices - test method for determining the acoustic performance - Part 5: intrinsic characteristics - in situ values of sound reflection and airborne sound insulation. CEN, Brussels, Belgium; 2003, ISO 13472-1. Acoustic measurement of sound absorption properties of road surfaces in situ - Part I: extended surface method. ISO, Geneva, Switzerland; 2002]. Since the absorption is an intrinsic property of the acoustic material, its measurement in either domain must provide the same result. However, this has not been formally demonstrated yet. The aim of this paper is to carry out a comparison between the absorption coefficient predicted by the impedance model of a Microperforated Insertion Unit and the absorption coefficient predicted from a simulated reflection trace taken into account the finite length of the time window.     

Effect of a honeycomb on the sound absorption characteristics of panel-type absorbers

Panel-type sound absorbers are commonly used to absorb low-frequency sounds. Recently, a new type of panel/membrane absorbers has been proposed as a next-generation sound absorber free from environmental problems. On the other hand, it is known that placing a honeycomb structure behind a porous layer can improve sound absorption performance and a similar effect can be obtained for microperforated-panel absorbers. Herein, the sound absorption characteristics of a panel sound absorber with a honeycomb in its back cavity are theoretically analyzed. The numerical results are used to discuss the variations in the sound absorption characteristics due to the honeycomb as well as the mechanism for sound absorption.     

Sound image method and sound energy vortex in rectangular room

1.TntroductionMostprob1emsofsolvingsoundficlds,suchassoundpressuredistributionsinroomsareclassiia1.lllIn10wfrequencyrange,wavemotionmethodisapplied.Inthemethod,thenorma1modesofroomaresolvedandthensummeduptocvaluatetheirunknownamplitudesbymatchingsoundsource.Inhighfrequencyrange,thenumberofnormalmodesneedcdisnumer0usandtogetfina1solutionwouldbeimpossiblebecauseofthetimeconsumptionincomputation.Hence,ther0omacousticsbasedongeometri-calacousticsandthestatisticswasdevcloped.Thewavemotionmethodcan…     

论声压级平均算法

本文阐述了求声压级平均值的几种算法,特别论述了对声压级数据直接进行算术平均的运算方法。     

Characterizing the sound quality of air-conditioning noise

The aim of the psychoacoustic study presented here was to characterize listeners' preferences for a set of sounds produced by different brands and models of indoor air-conditioning units. In addition, some synthetic sounds, created by interpolation between recorded sound samples, were integrated into the set. The multidimensional perceptual space and the corresponding physical space representative of the sound set were determined with multidimensional scaling (MDS). Then the preferences for different classes of listeners were related to the physical space. The best spatial model yielded by the MDS had three common dimensions and specificities. The three dimensions are correlated with the ratio of the noisy part of the spectrum to the harmonic part (NHR), with the spectral center of gravity (SC) and with loudness (N). Two classes of listeners can be distinguished in terms of preference. For one, preference varied primarily with loudness, whereas for the other it varied more with SC and NHR. However, for one class the preference grew with the parameter NHR, while it decreased for the other class. The results replicate under different laboratory conditions and indicate the usefulness of this sound quality assessment approach for characterizing appliance noises.     

On the accuracy of the ray-tracing algorithms based on various sound receiver models

In this paper, the effect of sound ray detection on the accuracy of sound field simulation by using the ray-tracing technique has been discussed. The current methods to define the receiver size have been briefly described. Then a new equation for the computation of the size of a receiver has been proposed and it has considered such factors as the size of the room, the number of initial rays and the distance from source to receiver. The corresponding algorithm has been compared with two other algorithms that are based on different receiver models. It can be concluded from the computed and measured results that the new model is applicable for more extensive situations.     

立体声技术近年来的进展

本文总结和评论了立体声技术近年来的进展，包括声像定位理论和实验，传统的双通路立体声系统的改进，环绕产系统，高清晰度电视声系统，假头型立体声系统，数字声频技术在立体声的应用等．文中最后还叙述了对立体声今后发展的展望．     

Towards standardization in soundscape preference assessment

The study of soundscapes involves diverse fields of practice, diverse approaches and diverse disciplinary interests. The field overlaps with the much larger and established field of environmental noise management, and also intersects, to various degrees, with other areas of acoustics such as sound quality, human acoustic comfort in buildings, and music—and also with non-acoustic fields such as wilderness and recreation management, urban and housing design, and landscape planning and management. Working Group 54 of ISO/TC 43/SC 1 has been formed with a remit of standardization for perceptual assessment of human sound preference (in outdoor space) using questionnaires. The working group began its work in 2009, with considerable and wide-ranging discussion amongst its members. This paper makes a range of observations, and sometimes suggestions, on matters pertinent to eventual definition of the soundscape; on outcomes of interest arising from experience of a soundscape; on the role of context in assessment; on sound sources in different places; and on relevant lessons for soundscape assessment from experience of questionnaire measurement of noise annoyance. It represents a personal view, though informed by a range of opinions from the Working Group meeting and from literature.