scholarly journals Evaluation of Concert Hall Auralization with Virtual Symphony Orchestra

2011 ◽  
Vol 18 (3-4) ◽  
pp. 349-366 ◽  
Author(s):  
Jukka Pätynen ◽  
Tapio Lokki
Keyword(s):  
Symphony Orchestra ◽  
Orchestral Music ◽  
Room Acoustics ◽  
Impulse Responses ◽  
Acoustic Parameters ◽  
The Real ◽  
Modeling Software ◽  
Concert Halls ◽  
The Difference ◽  
Better Than

Authenticity of the simulation of room acoustics is evaluated by comparing auralizations with real recordings. Impulse responses are recorded in two concert halls with 34 loudspeakers positioned on the stage in the shape of an orchestra and a 3D microphone probe for spatial reproduction. The acoustics of the same concert halls are simulated with acoustics modeling software. B-format impulse responses are calculated by using the identical source and receiver positions as in the real halls. Additionally, two processing methods are applied to the simulated responses in order to decrease the difference in acoustical impression. Objective room acoustic parameters between the real and simulated halls are compared, and a listening test utilizing convolutions with anechoic orchestral music is organized. The results suggest that the subjects can be categorized in two groups having preference of brightness or naturalness. Depending on the music style, auralizations with processed responses are assessed equal or better than the real hall in terms of instrument balance and brightness.

scholarly journals Toward realistic binaural auralizations – perceptual comparison between measurement and simulation-based auralizations and the real room for a classroom scenario

Acta Acustica ◽  
2021 ◽  
Vol 5 ◽  
pp. 8
Author(s):  
Matthias Blau ◽  
Armin Budnik ◽  
Mina Fallahi ◽  
Henning Steffens ◽  
Stephan D. Ewert ◽  
...  
Keyword(s):  
Impulse Responses ◽  
Point Scale ◽  
Present Contribution ◽  
The Real ◽  
Simulation Based ◽  
Perceptual Comparison ◽  
Better Than

In order to make full use of their potential to replace experiments in real rooms, auralizations must be as realistic as possible. Recently, it has been shown that for speech, head-tracked binaural auralizations based on measured binaural room impulse responses (BRIRs) can be so realistic, that they become indistinguishable (or nearly so) from the real room [1, 2]. In the present contribution, perceptual comparisons between the auralized and the real room are reported for auralizations based both on measured and simulated BRIRs. In the experiment, subjects sitting in the real room rated the agreement between the real and the auralized room with respect to a number of attributes. The results indicate that for most attributes, the agreement between the auralized and the real room can be very convincing (better than 7.5 on a nine-point scale). This was not only observed for auralizations based on measured BRIRs, but also for those based on simulated BRIRs. In the scenario considered here, the use of individual head-related impulse responses (HRIRs) does not seem to offer any benefit over using HRIRs from a head-and-torso-simulator.

scholarly journals The Effects of Adding Pyramidal and Convex Diffusers on Room Acoustic Parameters in a Small Non-Diffuse Room

Acoustics ◽  
2019 ◽  
Vol 1 (3) ◽  
pp. 618-643
Author(s):  
Hassan Azad ◽  
Julie Meyer ◽  
Gary Siebein ◽  
Tapio Lokki
Keyword(s):  
Statistical Analysis ◽  
Large Scale ◽  
Reverberation Time ◽  
Impulse Responses ◽  
Acoustical Parameters ◽  
Acoustic Parameters ◽  
Acoustical Properties ◽  
Measurement Results ◽  
The Difference ◽  
Rectangular Room

This paper presents an investigation of the effects of relatively large-scale pyramidal and convex-shaped diffusers on the acoustical properties of a small non-diffuse rectangular room. Room impulse responses (RIRs) were measured in various room configurations to extract the early decay time (EDT), reverberation time (T20), early-to-late arriving sound ratio (C50), and clarity (C80). The difference between the parameters measured in the empty room were chosen to be the reference, and those measured in other room configurations was calculated. Statistical analysis of the measurement results supplements the investigation to determine whether the coverage and type of diffusers contribute significantly to the variation of the acoustical parameters. The results show that adding diffusers in the room generally decreases EDT as well as T20, and increases C50 as well as C80 for both diffuser types. The statistical analysis shows that the coverage of diffusers significantly contributes to the variation of the acoustical parameters in most conditions (octave band, diffuser type). The effect of the diffuser shape is only significant for some of the conditions (at 4 kHz, the number of diffusers). The data presented demonstrate that in a small non-diffuse room the reverberation can be controlled efficiently by redirecting the sound energy towards the most absorbing surfaces.

Removal of inelastically scattered electrons substantially increases phase contrast on frozen-hydrated molecules

1987 ◽  
Vol 45 ◽  
pp. 652-653
Author(s):  
John P. Langmore ◽  
Brian D. Athey
Keyword(s):  
Electron Diffraction ◽  
Phase Contrast ◽  
Low Dose ◽  
Dark Field ◽  
Biological Structure ◽  
Bright Field ◽  
Low Contrast ◽  
Negative Stain ◽  
The Difference ◽  
Better Than

Although electron diffraction indicates better than 0.3nm preservation of biological structure in vitreous ice, the imaging of molecules in ice is limited by low contrast. Thus, low-dose images of frozen-hydrated molecules have significantly more noise than images of air-dried or negatively-stained molecules. We have addressed the question of the origins of this loss of contrast. One unavoidable effect is the reduction in scattering contrast between a molecule and the background. In effect, the difference in scattering power between a molecule and its background is 2-5 times less in a layer of ice than in vacuum or negative stain. A second, previously unrecognized, effect is the large, incoherent background of inelastic scattering from the ice. This background reduces both scattering and phase contrast by an additional factor of about 3, as shown in this paper. We have used energy filtration on the Zeiss EM902 in order to eliminate this second effect, and also increase scattering contrast in bright-field and dark-field.

PENERAPAN MODEL PEMBELAJARAN KOOPERATIF TIPE STAD DENGAN PENDEKATAN RME UNTUK MENINGKATKAN HASIL BELAJAR MATEMATIKA SISWA KELAS IX SMP MUHAMMADIYAH PADANG LUAS KECAMATAN TAMBANG KABUPATEN KAMPAR

2018 ◽  
Vol 2 (5) ◽  
pp. 744
Author(s):  
Zainur Zainur
Keyword(s):  
Action Research ◽  
Cooperative Learning ◽  
Student Learning ◽  
Learning Outcomes ◽  
Mathematics Learning ◽  
Student Learning Outcomes ◽  
Learning Model ◽  
Research Instrument ◽  
The Difference ◽  
Better Than

This research was motivated by the low learning outcomes of grade IX SMP Muhammadiyah Padang LuasKecamatan Tambang Kabupaten Kampar. This study aims to improve learning outcomes in mathematicslearning through STAD type cooperative learning with the RME approach in class IX SMP MuhammadiyahPadang Luas Kecamatan Tambang Kabupaten Kampar. The subjects of this study were all classes IX in SMPMuhammadiyah Padang Luas Kecamatan Tambang Kabupaten Kampar totaling 26 people. The form ofresearch is classroom action research. This research instrument consists of performance instruments and datacollection instruments in the form of teacher activity observation sheets and activities. The results of the studystated that there were significant differences between students' mathematics learning outcomes before applyingthe STAD type cooperative learning model with the RME approach with after applying the STAD typecooperative learning model with the RME approach. The difference shows student learning outcomes after theaction is better than before the action with completeness reaching 80.77% or 21 completed. Based on the resultsof the study and discussion it can be concluded that the application of STAD type learning model with RealisticMathematic Education (RME) approach can improve the learning outcomes of grade IX students of SMPMuhammadiyah Padang Luas Kecamatan Tambang Kabupaten Kampar on statistical material.

ANALYTICAL INDICATOR. ANALYSIS OF THE REAL STATE OF DYNAMICS OF MORTALITY OF THE POPULATION OF RUSSIA FROM MALIGNANT TUMORS AND CHANGES IN ITS STRUCTURE

2019 ◽  
Vol 65 (2) ◽  
pp. 205-219 ◽  
Author(s):  
V. Merabishvili
Keyword(s):  
Malignant Tumors ◽  
Specific Weight ◽  
Mortality Rates ◽  
Retirement Age ◽  
Medium Term ◽  
Age Composition ◽  
The Real ◽  
Indicator Analysis ◽  
The Difference ◽  
Real State

The mortality rate is one of the most important criteria for assessing the health of the population. However, it is important to use analytical indicators correctly, especially when evaluating time series. The value of the “gross” mortality is closely linked with a specific weight of persons of elderly and senile ages. All international publications (WHO, IARC, territorial cancer registers) assess the dynamics of morbidity and mortality only by standardized indicators that eliminate the difference in the age composition of the compared population groups. In Russia, from 1960 to 2017, the share of people of retirement age has increased more than 2 times. The structure of mortality from malignant tumors has changed dramatically. The paper presents the dynamics of gross and standardized mortality rates from malignant tumors in Russia and in all administrative territories. Shows the real success of the Oncology service. The medium-term interval forecast until 2025 has been calculated.

scholarly journals Six ultraviolet minutes for cleaner operating theatres

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
R Bosco ◽  
S Gambelli ◽  
V Urbano ◽  
G Cevenini ◽  
G Messina
Keyword(s):  
Cross Sectional Study ◽  
Cross Sectional ◽  
Before And After ◽  
Operating Theatres ◽  
Cleaning Procedures ◽  
The Difference ◽  
Contamination Levels ◽  
Different Levels ◽  
Better Than ◽  
Final Cleaning

Abstract Background Sanitizing the operating theatres (OT) is important to minimize risk of post-operative infections. Disinfection procedures between one operation and another is less aggressive than final cleaning procedures, at the end of the day. Aim was assessing the difference of contamination: i) between different levels of disinfection; ii) before and after the use of a UVC Device (UVC-D). Methods Between December 2019/February 2020 a cross sectional study was conducted in OT in a real clinical context. 94 Petri dishes (PD) were used in 3 OT. Three different sanitation levels (SL1-3) were compared pre- and post-use of UVC-D: i) No cleaning after surgery (SL1); ii) after in-between cleaning (SL2); iii) after terminal cleaning (SL3). UVC-D was employed for 6 minutes, 3 minutes per bed side. PD were incubated at 36 °C and colony forming unit (CFU) counted at 48h. Descriptive statistic, Wilcoxon and Mann-Whitney tests were performed to assess the contamination levels in total, pre/post use of UVC-D, and between different sanitation levels, respectively. Results In total we had a mean of 3.39 CFU/PD (C.I. 2.05 - 4.74) and a median of 1 CFU/PD (Min. 0 - Max. 39), after UVC-D use we had a mean of 2.20 CFU/PD (C.I. 0.69 - 5.09) and a median of 0 CFU/PD (Min. 0 - Max. 133). The UVC-D led to a significant reduction of CFU (p < 0.001). Without UVC-D we had a significant CFU drop (p < 0.05) between SL1 and SL3. Using UVC-D, we observed significant reductions of contamination (p < 0.05) between SL3 and SL1. Comparing SL1 (median 0) post UVC-D use vs SL2 pre UVC-D use (median 0.5), and SL2 post UVC-D use (median 0) vs SL3 pre UVC-D use (median 1) we had a significant reduction of contamination (p < 0.05). Conclusions UVC-D improved environmental contamination in any of the three sanitation levels. Furthermore, the use of UVC-D alone was better than in-between and terminal cleaning. Although these encouraging results, the cleaning procedures executed by dedicated staff has to be considered. Key messages UVC are efficient to decrease contamination in operating theatres regardless of sanitation levels. The additional use of UVC technology to standard cleaning procedures significantly improves sanitation levels.

Influence of Collagen Status on Microstructures of Porous Collagen/TCP Composites

2007 ◽  
Vol 330-332 ◽  
pp. 495-498
Author(s):  
Chao Zou ◽  
Wen Jian Weng ◽  
Xu Liang Deng ◽  
Kui Cheng ◽  
Pi Yi Du ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Cell Growth ◽  
Tricalcium Phosphate ◽  
Freeze Drying ◽  
Alkali Treatment ◽  
Test Results ◽  
Collagen Matrices ◽  
The Difference ◽  
Porous Composites ◽  
Better Than

Two starting collagens, sponge and floc collagen, were used to prepare collagen/tricalcium phosphate (TCP) composites. The resulting composites were porous and had 200μm pore size. However, there was a difference in the microstructure of the pore walls for the composites derived from the two collagens, the pore walls in sponge collagen/TCP composite were still porous and had 200 nm micropores size, TCP particles were trapped in collagen matrices. While floc collagen/TCP composite had smooth and dense walls in which TCP particles were embedded. The difference could be attributed to the starting collagen with different status. Sponge collagen has a soft structure, which easily becomes disassembled fibrils during alkali treatment, the disassembled fibrils are integrated again to form a dense morphology for pore walls after freeze-drying. While floc collagen has already a low disassembly degree, the alkali treatment could not be able to separate the fibrils, this remains as micropores in pore walls after freeze-drying. Both porous composites are significant in bone tissue engineering or regeneration. MTT test results showed the two composites had good cytocompatibility, and sponge collagen/TCP composite was somewhat better than floc collagen/TCP composite, which could result from that micropores derived roughness in pore walls of sponge collagen/TCP composite is suitable for cell growth.

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