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The characteristics of light equipment were investigated to understand their acoustic properties and effects in a television (TV) studio. The absorption coefficients were measured in a reverberation chamber with representative spotlights of 1 kW and 2 kW. Based on the absorption coefficients, laboratory tests using a 1:10 scale model of the test specimens were designed. The purpose of the experiment was to identify the absorption and scattering characteristics, including the coverage density, angle, and the presence/absence of barn doors. The results showed that the averaged absorption coefficients varied from 0.04 to 0.13, and the averaged scattering coefficients ranged from 0.35 to 0.81 as the coverage density varied from 5 to 16%, respectively. When the height position of the light was varied from 9 m to 3.5 m in the TV studio, it was found that the sound strength increased to 0.71 dB, and the clarity (C50) decreased to 0.30 dB. At a low height of 3.5 m, the reverberation time (T20) and the early decay time (EDT) increased for frequencies below 500 Hz and decreased for frequencies above 500 Hz. The use of light equipment increased the sound strength; however, the variation in both T20 and C50 was only slight. The standard deviation of the EDT and C50 in the space decreased by 16% and 43%, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary Summary Increase in local temperature during light exposure of biological tissues plays an important role in determining the fate of most therapeutic modalities. Variations in the optical properties (absorption coefficient, scattering coefficient, anisotropy factor, optical depth etc.) of two cancer cell lines “Rhobdomyosarcoma and Cervical carcinoma” due to gradual increase in temperature were determine quantitatively with a double integrating sphere system. It was observed that all three coefficients showed decreasing tendency as the temperature increases for both the cell lines except for scattering coefficient of HeLa which remain constant within error limit. Anisotropy factor for both cell lines increased indicating temperature dependent subcellular density variations. Temperature dependent optical properties information may lead to precise dosimetry and could help clinicians for predicting the therapeutic modality outcome. [ABSTRACT FROM AUTHOR]

Abstract: The acoustical influence of organ pipes on the sound fields within a performing space was investigated. Test specimens with appropriate characteristics were determined after a field survey of various prospect pipes. Laboratory tests using 1:10 scale models were carried out to identify the surface characteristics of an organ's prospect pipes. The absorption, scattering and diffusion coefficients of the prospect pipes were found to range from 0.09 to 0.10, 0.11 to 0.31, and from 0.18 to 0.37, respectively. From the field measurements made in a large concert hall with a pipe organ on the right lateral wall, higher G and LF E4 values were observed at positions nearer the pipe organ. Additionally, a computer simulation was employed to identify the acoustic properties of the pipe organ within a hall. As a result, it was derived that the pipe organ, including the prospect pipes and the organ enclosure had an absorption coefficient of 0.21 with higher absorption at lower frequency bands and an average scattering coefficient of 0.50. [Copyright &y& Elsevier]

We present the results from a study of the particulate scattering properties of three bodies of water that represent a wide range of optical properties found in inland waters. We found a positive linear relationship (R² = 0.45, P< 0.005) between the mass-specific scattering coefficient at 532 nm (bp*(532)) and the ratio of the inorganic suspended material (ISM) to the total suspended material (TSM) in our study areas. In con-trast to earlier studies in which bp*(532) was lower for inorganic particles than for organic particles, we found that the value of fap*(532) for ISM (bp*(532),SM = 0.71 m²/g) was approximately 1.6 times greater than the value found for organic suspended materials (OSM) (bp*(532)0sM = 0.45 m²/g). We found that the dependence of the particle scattering coefficient (bp) on wavelength (λ) could be described accurately by a power law (with mean average percent error (MAPE) < 0.07) in waters dominated by inorganic particles. The model errors in waters dominated by organic particles, however, were much larger (MAPE > 0.1 ), especially in the spectral region associated with strong phytoplankton absorption. The errors could be reduced over this wavelength range by adding a term to the model to account for particle absorption, but the additional term tended to increase the error outside of this range. We conclude that information about the nature of the scatter-ing particles in lake waters is necessary for the selection of an appropriate model for particle absorption and that a hybrid model that includes absorption over some wavelength ranges may be necessary. [ABSTRACT FROM AUTHOR]

In an urban environment, visibility strongly reflects human safety and welfare. Generally, visibility is dependent on particle scattering and absorption. The former is influenced by light wavelength, atmospheric gaseous species and particle characteristics, especially number and size distribution. Therefore, it is necessary to establish the relationship between visibility and particle characteristics. Furthermore, it is important to understand the formation mechanism of secondary aerosols. In this study, a micro-orifice uniform deposit impactor (MOUDI) was used to measure the particle size distribution. At the same time, the particle scattering coefficient was measured with a nephelometer. After sampling, the chemical compositions of the particulates were analyzed via ion chromatography (IC) and a total organic carbon (TOC) analyzer. The results show that coarse particulates are not related to the scattering coefficient, whereas the scattering coefficient is slightly relative to the fine particle mass concentration. From the measured scattering coefficient, the visibility was calculated to be in the range of 20,000 to 120,000 m. The predicted visibility is greater than the observed data, ranging from 18,000 to 100,000 m at the Song-Sun Airport. [ABSTRACT FROM AUTHOR]

Abstract: With the aim of studying the optical properties of ‘Pink Lady®’ apples measured by TRS during storage in normal atmosphere and of relating them to fruit maturity and structural characteristics, 60 apples, measured at harvest by TRS at 670nm and in the spectral range 740−1100nm, were ranked on the basis of decreasing μa670 (increasing maturity) and randomized into 6 batches corresponding to 6 times of analysis: at harvest and after 7, 15, 29, 66 and 91 days of storage at 1°C. At each storage time, apples were measured by TRS in the same spectral range as at harvest, and firmness, intercellular space volume (RISV), soluble solid content (SSC) and starch hydrolysis were measured; Streif Index and weight loss were computed. Overall, the μa spectra showed a maximum at 670nm (chlorophyll-a) and at 980nm (water), while the μ’s spectra had a decreasing trend with the wavelength increase. The μa670 and μa980 decreased with storage time as a consequence of a decrease in chlorophyll and water contents, respectively. The size and the density of the scattering centers were affected by the interplay of various phenomena: starch hydrolysis, flesh softening, water loss and RISV increase. High correlation coefficients were found between μa in the spectral region 920−1100nm and firmness, Streif Index and RISV, while low correlation coefficients were observed between μa and SSC, and between μ’s and all the quality parameters. Using PLS analysis, good prediction for firmness, RISV and Streif Index were obtained using μa spectra; models’ performance improved when μa and μ’s are combined. [Copyright &y& Elsevier]

Rationale and Objectives: We sought to investigate the utility of phase-contrast diffuse optical tomography (PCDOT) for differentiation of malignant and benign breast masses in humans and to compare PCDOT with conventional diffuse optical tomography (DOT) for analysis of breast masses in humans. Materials and Methods: Thirty-five breast masses were imaged in 33 patients (mean age, 51 years; range, 22–80) using PCDOT. Images characterizing the tissue refractive index, and absorption and scattering coefficients of breast masses were obtained with a finite element-based reconstruction algorithm. Theses images were then analyzed and compared with the biopsy/pathology results for all the cases examined. Results: Malignant lesions tended to have a decreased refractive index, allowing them to be discriminated from benign lesions in most cases, whereas absorption and scattering images were unable to accurately discriminate benign from malignant lesions. The sensitivity, specificity, false-positive value, and overall accuracy for refractive index imaging were 81.8%, 70.8%, 29.2%, and 74.3%, respectively. The accuracy of refractive index imaging increases with increasing patient age. Conclusion: Refractive index is a new parameter for optical imaging that may be helpful in differentiating between malignant and benign masses in the breast. [Copyright &y& Elsevier]

We propose a learning-based multi-view stereo (MVS) method in scattering media, such as fog or smoke, with a novel cost volume, called the dehazing cost volume. Images captured in scattering media are degraded due to light scattering and attenuation caused by suspended particles. This degradation depends on scene depth; thus, it is difficult for traditional MVS methods to evaluate photometric consistency because the depth is unknown before three-dimensional (3D) reconstruction. The dehazing cost volume can solve this chicken-and-egg problem of depth estimation and image restoration by computing the scattering effect using swept planes in the cost volume. We also propose a method of estimating scattering parameters, such as airlight, and a scattering coefficient, which are required for our dehazing cost volume. The output depth of a network with our dehazing cost volume can be regarded as a function of these parameters; thus, they are geometrically optimized with a sparse 3D point cloud obtained at a structure-from-motion step. Experimental results on synthesized hazy images indicate the effectiveness of our dehazing cost volume against the ordinary cost volume regarding scattering media. We also demonstrated the applicability of our dehazing cost volume to real foggy scenes. • A novel cost volume for learning-based multi-view stereo in scattering media. • Airlight and scattering coefficient estimation with our dehazing cost volume. • Demonstrating depth estimation on synthetic and actual foggy images. [ABSTRACT FROM AUTHOR]

The optical properties of aerosol particles must be clearly understood to reduce uncertainty in the prediction of the global climate change. Simultaneous measurements of scattering and absorption coefficients of aerosol particles were conducted in the atmospheric boundary layer over the western North Pacific and the Southern Ocean. For the scattering coefficient, total scattering and backscattering coefficients were measured at three different wavelengths. Over the western North Pacific, significant differences in the Ångström exponent and absorption coefficient were found between polluted and pristine air masses. Over the parts of the Southern Ocean free of sea ice, the Ångström exponent and the ratio of the back-to total-scattering coefficients were uniform. However, over the sea-ice regions, the scattering coefficients were an order of magnitude lower, and the Ångström exponent an order of magnitude higher, than over the parts of the ocean free of sea ice. These differences appear to be due to the fact that the emission of aerosol precursors and sea salt particles is suppressed by sea ice. This study represents the difference in aerosol optical properties as a function of source region and sea condition. These results will contribute to improving the accuracy of estimates of the direct radiative forcing effects due to aerosol particles. [ABSTRACT FROM AUTHOR]

In the present work, we propose a novel algorithm to determine the scattering coefficient of OA by evaluating the relationships of the MSEs for primary organic aerosol (POA) and secondary organic aerosol (SOA) with their mass concentrations at three distinct sites, i.e. an urban site, a rural site, and a background site in China. Our results showed that the MSEs for POA and SOA increased rapidly as a function of mass concentration in low mass loading. While the increasing rate declined after a threshold of mass loading of 50 μg/m3 for POA, and 15 μg/m3 for SOA, respectively. The dry scattering coefficients of submicron particles (PM 1) were reconstructed based on the algorithm for POA and SOA scattering coefficient and further verified by using multi-site data. The calculated dry scattering coefficients using our reconstructing algorithm have good consistency with the measured ones, with the high correlation and small deviation in Shanghai (R2 = 0.98; deviations: 2.9%) and Dezhou (R2 = 0.90; deviations: 4.7%), indicating that our algorithms for OA and PM 1 are applicable to predict the scattering coefficient of OA and Submicron particle (PM 1) in China. Image 1 • The variations of MSEs for POA and SOA were investigated. • The MSEs for POA and SOA increased rapidly as a function of mass concentration in low mass loading. • MSEs declined at the threshold of mass loading were 50 and 15 μg/m3 for POA and SOA, respectively. • The algorithm for scattering coefficient of ambient OA were reconstructed. [ABSTRACT FROM AUTHOR]

The understanding of the dispersion chemistry of papermaking grade fillers is as important as their effect on paper. Magnesium silicate (talc) is one of the major fillers used for papermaking. It is hydrophobic and chemically inert. The dispersion chemistry of talc of different particle sizes was studied with wetting agent (non-ionic triblock copolymer) and anionic dispersant (sodium salt of polyacrylic acid). Both wetting agent and dispersant were added in talc slurry separately and in combination. The dispersion behavior was studied through measuring the Brookfield viscosity. The wetted and dispersed talc was also added to paper to understand its effect on papermaking process and paper properties. Wetting and dispersion changed the colloidal charge chemistry of talc making it more anionic which reduced the talc retention in paper. Lowering the particle size of talc significantly improved the light scattering coefficient (LSC) of paper and decreased its retention. Controlling colloidal charge of papermaking suspension with cationic polyacrylamide polymer helped in protecting the retention of talc without affecting the LSC of both filler and paper. [ABSTRACT FROM AUTHOR]