共查询到18条相似文献,搜索用时 109 毫秒
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北京工人俱乐部始建于50年代初,在戏剧界被认为是国内演出京剧音质最好的大厅。但出于结构安全和多用途使用方面的需要,于1987年进行翻建。翻建后的观众厅要求保持京剧演出时原有的音质水平,同时,在声学上要适应多用途的需要。对此,采用了可调混响结构,并对大厅的体形、每座容积、增强早期反射声等方面也作了改进。该工程于1988年10月竣工。通过声学测定和试用表明,大厅的声学设计达到了预期目的,特别在扩大低频混响的可调幅度方面取得了新的进展。 相似文献
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中国传统戏场在世界建筑史中别具一格,它与现代剧院迥然不同。传统戏曲表演是虚拟化的,因此可在面积不大的亭式舞台上演出,形成三面围观的格局。这类戏场以顶面敞开的庭院形式为其主流。本文讨论了下列相关声学问题:(1)亭式舞台的演唱效果;(2)庭院式戏场的混响感;(3)不同戏场布局的声场强度(响度)变化;(4)伴奏乐队位置变迁的声学效果;(5)舞台下设瓮助声之谜剖析。 相似文献
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本文简述环境声学的发展过程以及在厅堂音质、环境噪声和噪声控制方面的新世纪展望。 相似文献
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建筑声学的理论和实践已有100多年的历史.虽然对于要求高质量音乐演出的厅堂,仍然存在着需要进一步探讨的原理和处理技术,但总的来说,对于不同功能的厅堂,在声学要求上已有一系列音质设计的准则和方法.对于从事建筑设计的工程技术人员,却有时难以全面掌握音质设计的基础要求. 王季卿教授新著《建筑厅堂音质设计》一书(2001年 1月由天津科技出版社出版),全面论述了音质设计的原理和技术:既阐述了系统的基础理论,又介绍了最新的研究进展;既讲清了音质设计中的声学原理,又对各种功能的厅堂介绍了典型的设计实例,使设计… 相似文献
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本文对近年来音乐厅音质设计中若干问题的进展作一述评。(1)在已建立的众多独立音质参量基础上,如何作出大厅综合评价,就需要考虑到它们的互动性和贡献权,方法学将成为关键。(2)空间感已确认由声源视在展宽度ASW和听者环绕感LEV组成,对于影响两者的诸多复杂因素有了较深入研究,这声场中的细节又将如何与大厅设计相联系亦备受关注。(3)听众及座椅吸声这个老问题有了新的研究成果,对于空、满场的声学关系已积累了更多资料,使大厅音质的估算更为精确可靠。(4)常说扩散对大厅音质很重要,但其主观效应仍然处于玄虚状态,一些新的主观试听实验结果还不足以说明问题。 相似文献
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上海大剧院观众厅的音质设计与研究 总被引:1,自引:0,他引:1
上海大剧院是目前我国规模最大、起点最高、技术最新、音质优良的现代化大剧院。本文重点介绍上海大剧院的规模特点、观众厅音质设计技术要求、体形设计特点、混响控制设计、声学模拟试验研究及音质性能和主观评价等。 相似文献
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The Grand Theater in the Sejong Performing Arts Center in Seoul, Korea is a proscenium hall with 3022 seats. Originally built in 1978, the Grand Theater was remodeled in 2004 to provide variable reverberation time (RT) using a sound system. Recently, a second remodeling was scheduled to enhance the hall’s acoustic quality, especially its RT, sound strength (G) and binaural quality index (BQI = 1-IACCE3), based on architectural acoustic analysis. In the remodeling plan, the wall covering and chair materials were changed to produce longer RT and higher G. For the remodeling design, side balconies were added to the first and third floors to provide lateral reflections to the audience area. The orchestra shell and various ceiling/wall reflectors were planned to provide more early reflections to the audience area. To verify the design, the effects of these structures on the sound pressure levels and spatial parameters of early sound in the audience area were investigated by open-type 1:10 scale model measurement. In addition, the acoustical qualities of the remodeled hall were evaluated using computer simulations and 1:50 scale model measurement. The results show that G was improved by 5 dB and BQI by 0.24, whereas the occupied RT at mid-frequencies became variable from 1.47 to 2.24 s. 相似文献
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Ternström S Cabrera D Davis P 《The Journal of the Acoustical Society of America》2005,118(6):3903-3911
Four volunteer members of the chorus of Opera Australia, representing four different voice categories, wore binaural pairs of wireless microphones during a penultimate dress rehearsal on the Opera Theater stage of the Sydney Opera House. From the recordings, data were obtained on sound levels and on the self-to-other ratios (SORs). The sound levels were comparable to those found in loud music in chamber choir performance. The average SOR ranged from +10 to +15 dB. Compared to chamber choirs in other types of room, the SOR values were high. On a separate occasion, the stage support parameters ST1 (early reflections) and ST2 (late reflections) were measured over the whole stage area. ST1 was about -16 dB, which is typical for opera stages, and -20 dB for ST2, which is unusually low. It is concluded that the SOR in the opera chorus depends mostly on choir formation, which is highly variable, and that an opera chorus artist generally can hear his or her own voice very well, but little of the others and of the orchestra. This was confirmed by informal listening to the recordings. 相似文献
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The nonlinear dynamics of a waveguide CO2 laser with combined periodic loss and pumping modulation is investigated theoretically and experimentally. The possibilities
of controlling time and energy parameters of the output radiation using the corresponding selection of the detuning of the
cavity's longitudinal mode from the center of the amplification line, the amplitude, and the frequency of loss modulation
are demonstrated. The observed asymmetric dependence of the lasing-radiation density on the detuning of the cavity frequency
is explained by the attendant modulation of the refractive index of the loss modulator.
To whom correspondence should be addressed.
B. I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, 68, F. Skorina Ave., Minsk, 220072, Belarus.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 4, pp. 471–478, July–August, 1999. 相似文献
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本文介绍了用ICP-AES测定稀土镁合金中稀土总量、钙、镁、锰、铁的方法,其中,稀土总量以铈的量进行换算,而铈 的测量通道通过扩展手段来设置。文中对样品的处理、测定的条件进行了较详细的研究,并对测量的精密度、准确度进行了考查。实验证明,该方法简便、结构可靠。 相似文献
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K. P. Kureichik S. N. Pupkevich V. S. Granos I. S. Kharamchenkov 《Journal of Applied Spectroscopy》1999,66(5):851-854
We describe a modified GELIOS System intended to automate the atomic-absorption spectrometers AAS, S115, SATURN, and Perkin-Elmer
503. Software is prepared in the visual environment of programming DELFI-3 and functions under the control of Windows 95.
A distinguishing feature of the GELIOS System is simultaneous search for the peak and area of the absorption signal, correction
of the errors of measurements, automatic digital filtration of data, control of the time of operation of hollow-cathode lamps,
measurement of spectra and the statistical resource of the service life of hollow-cathode lamps, use of different methods
to construct a calibrating graph, the possibility of memorizing the data of the analysis in an archived file, and a formation
of the report for printing. The system contains an electrovic data directory on atomicabsorption analysis in five volumes
for 67 elements of the Mendeleev system.
To whom correspondence should be addressed.
“University” Science and Production Center, 4, F. Skorina Ave., Minsk, 220050, Belarus. Translated from Zhurnal Prikladnoi
Spektroskopii, Vol. 66, No. 5, pp. 734–737, September–October, 1999. 相似文献
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基于高光谱技术的酸奶中常见致病菌的快速鉴别及计数 总被引:1,自引:0,他引:1
酸奶是一种发酵型乳制品饮料,因其特殊的功能性和良好的口感而广受欢迎。但由于商业链的不正当运行,如奶源非法获取、灭菌不充分等原因,导致酸奶中致病菌大量滋生,酸奶中毒事件频繁发生。酸奶中常见的致病菌主要有大肠杆菌、金黄色葡萄球菌和沙门氏菌,这三种致病菌由人体摄入并达到一定的数量时会产生腹痛、腹泻等严重的消化道疾病,并且会破坏人体肠道内的正常菌群平衡,因此国标对奶制品中这三种致病菌的数量已有明确的限量规定。由于酸奶的主要消费对象为老人和小孩,故其潜在危害不容小觑。传统菌落检测方法虽具有简单,灵敏、可操作性强等优点,但当不同菌落混杂在一起时无法同时进行定性定量的检测,且具有试剂成本高,检测周期长,人为因素影响较大等缺点。因此开发一种快速、简单、准确的混合鉴定计数方法为避免致病菌对酸奶的潜在危害提供了有效的途径。高光谱技术同时包含样本的光谱信息与图像信息,既能够根据化学组分的微小变化进行精确识别(光谱信息),又能够反映出菌株在外部多层次的变化(图像信息)。因此该研究尝试对比高光谱图像技术和光谱技术,采用模式识别的方法,对比不同的模型识别结果,优选出最佳识别率的识别模型作为计数模型,最后通过最佳鉴别计数模型的识别分类结果来达到对酸奶中常见致病菌鉴定计数的目的。首先,购买酸奶中常见的乳酸菌种(保加利亚乳杆菌、嗜热链球菌、嗜酸乳杆菌、干酪乳杆菌、植物乳杆菌)和潜在污染的致病菌种(金黄色葡萄球菌、大肠杆菌、沙门氏菌)等标准菌株进行培养,提取经过48 h培养后的菌落图像信息和光谱信息。采用几种不同的预处理方式(SNV,MC,MSC,1stDER,2ndDER)对所提取的光谱数据进行预处理,并应用遗传算法筛除光谱数据中冗余的波段,保留有效波段。利用图像处理技术对图像信息中的菌株与培养基背景进行去除,然后采用主成分分析法从每幅图中优选出3个特征波长,并运用图像处理技术从特征波长所对应图像中提取菌株的18个基于GLCM的纹理特征信息。挑选合适的主成分分别建立不同的鉴别模型(LDA,KNN,BP-ANN,LS-SVM),通过其最终的鉴别模型的识别率来确定最佳鉴别计数模型。最后从标准菌株中分别挑选出30株进行计数测试,通过比较模式识别的分类数量结果与菌株的实际数量来验证模式识别效果的准确率。研究表明,运用SNV预处理后光谱数据在提高信噪比效果上明显优于其他几种预处理方式。745.790 8,773.098 4和779.207 0 nm为图像信息中方差贡献率最大的三个波长,运用从特征波长所对应的图像中所提取的纹理特征信息建立图像识别模型。通过对比图像信息和光谱信息的模式识别结果发现,光谱特征鉴别模型普遍优于图像纹理特征鉴别模型,且当主成分数为9时,运用光谱特征所建立的LS-SVM模型的校正集识别率为96.25%,预测集的识别率为91.88%,为最优模型。采用优选的最优模型对菌株进行识别计数,大肠杆菌计数的相对误差为3.33%,金黄色葡萄球菌和沙门氏菌计数的相对误差均为0,验证了高光谱技术应用于酸奶中常见致病菌的鉴别计数的可行性。 相似文献