Absorption, Transmission, Reflection

2020 ◽  
pp. 243-270
Author(s):  
Roland Wittje
Keyword(s):  
Standardized Testing ◽  
Construction Materials ◽  
Global Scale ◽  
Acoustic Properties ◽  
Materials Testing ◽  
Measurement Systems ◽  
Media Technologies ◽  
Scientific Principles ◽  
Musical Listening

This chapter discusses the genealogy of construction materials testing at acoustic laboratories founded in the late 1920s and 1930s, through the example of Norges Tekniske Høgskole (NTH) in Trondheim, Norway. Whereas architectural acoustics entailed mainly fieldwork, in the form of on-site research and consulting, the standardized testing of materials required idealized laboratory conditions where acoustic behavior could be isolated and reduced to the parameters of absorption, transmission, and reflection. With the rise of the acoustic laboratory, “objective” measurement systems replaced musical listening as a crucial skill for acousticians. Electroacoustic media technologies quickly spread on a global scale, yet acoustic laboratories still catered to the needs of local markets. One of these requirements was resource optimization, and the objective of standardized testing generally was less to improve the quality of construction than to optimize its cost. Traditional materials and buildings often exhibited better acoustic properties than the new constructions based on scientific principles.

Uji Marshall Pada Campuran AC-WC Dengan Substitusi Filler

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Zainal Abidin ◽  
Bunyamin Bunyamin ◽  
Febrina Dian Kurniasarir
Keyword(s):  
Construction Materials ◽  
Oyster Shell ◽  
Materials Testing ◽  
Filler Materials ◽  
Type Ii ◽  
Asphaltic Concrete ◽  
Asphalt Content ◽  
Materials Used ◽  
The Stability

To improve the quality of pavement can be achieved by substituting filler materials. The materials used for mixing asphaltic concrete are Portland Cement (PC) Andalas type II and Krueng Neng Oyster Shell (ACT) to bind the aggregate with the mixture of asphalt becoming denser as the ACT contains silica and lime. The use of ACT as a filler is expected to improve the quality of the pavement mixture. The study aimed to determine the effect of Marshall Parameters on the use of PC-substituted ACT fillers with a composition of 0% ACT: 100% PC, 20% ACT: 80% PC, 50% ACT: 50% PC, 80% ACT: 20% PC , and 100% ACT: 0% PC against AC - WC mixture. The number of construction materials testing in this study was 66. The research method was Bina Marga 2010 Revision 4 of 2018. The results showed that all compositions met the requirements for the Bina Marga 2010 Revision 4 2018 specification, the best composition for ACT and PC filling substitutes were obtained a percentage of 20% ACT and 80% PC at 5.00% of the asphalt content, the stability value was 1323.01 kg with a VIM value of 3.66% VMA 15.91% VFA 76.99 and MQ 508.68 kg / mm.

scholarly journals Dual UV-Thermal Curing of Biobased Resorcinol Epoxy Resin-Diatomite Composites with Improved Acoustic Performance and Attractive Flame Retardancy Behavior

2021 ◽  
Vol 2 (1) ◽  
pp. 24-48
Author(s):  
Quoc-Bao Nguyen ◽  
Henri Vahabi ◽  
Agustín Rios de Anda ◽  
Davy-Louis Versace ◽  
Valérie Langlois ◽  
...  
Keyword(s):  
Heat Release ◽  
Flame Retardant ◽  
Epoxy Resin ◽  
Flame Retardancy ◽  
Sound Absorption ◽  
Flexural Modulus ◽  
Construction Materials ◽  
Acoustic Properties ◽  
Low Frequencies ◽  
Compacting Pressure

This study has developed novel fully bio-based resorcinol epoxy resin–diatomite composites by a green two-stage process based on the living character of the cationic polymerization. This process comprises the photoinitiation and subsequently the thermal dark curing, enabling the obtaining of thick and non-transparent epoxy-diatomite composites without any solvent and amine-based hardeners. The effects of the diatomite content and the compacting pressure on microstructural, thermal, mechanical, acoustic properties, as well as the flame behavior of such composites have been thoroughly investigated. Towards the development of sound absorbing and flame-retardant construction materials, a compromise among mechanical, acoustic and flame-retardant properties was considered. Consequently, the composite obtained with 50 wt.% diatomite and 3.9 MPa compacting pressure is considered the optimal composite in the present work. Such composite exhibits the enhanced flexural modulus of 2.9 MPa, a satisfying sound absorption performance at low frequencies with Modified Sound Absorption Average (MSAA) of 0.08 (for a sample thickness of only 5 mm), and an outstanding flame retardancy behavior with the peak of heat release rate (pHRR) of 109 W/g and the total heat release of 5 kJ/g in the pyrolysis combustion flow calorimeter (PCFC) analysis.

The First Very Broadband Mediterranean Network: 30 Yr of Data and Seismological Research

2019 ◽  
Vol 91 (2A) ◽  
pp. 787-802
Author(s):  
Silvia Pondrelli ◽  
Francesca Di Luccio ◽  
Laura Scognamiglio ◽  
Irene Molinari ◽  
Simone Salimbeni ◽  
...  
Keyword(s):  
Seismic Source ◽  
Global Scale ◽  
Anthropogenic Noise ◽  
Earth Structure ◽  
Backbone Network ◽  
Early Adoption ◽  
Stable Conditions ◽  
Remote Sites ◽  
The Mediterranean

Abstract Starting in 1988, with the installation of the first broadband (BB) instrument in Italy, the Mediterranean Very Broadband Seismographic Network (MedNet) program established a backbone network of BB stations of the highest quality in the Mediterranean Sea countries. The Mediterranean region is characterized by relevant and frequent seismicity related to its complex tectonics, due to the convergence of two major plates, Africa and Eurasia, and the involvement of other minor plates, as the Adriatic plate. Therefore, the MedNet project became a scientific research infrastructure of excellence, able to fill the gap of regional coverage when the availability of seismic BB instruments was still scarce. The main characteristics of the MedNet network are the highest quality of the seismographic instrumentation at remote sites and very low level of anthropogenic noise with stable conditions of pressure and temperature. After 30 yr of recordings, the MedNet program has proven that the early adoption of very BB instruments in selected sites have been the best choice. A large number of studies benefited from MedNet data, as seismic source computation and Earth structure reconstruction, at local and global scale. We present a concise overview of the contribution given by MedNet data in the last three decades to motivate and financially support the existence of this valuable infrastructure, and to further maintain this project.

scholarly journals Spectral shapes and parameters from three different wave sensors

2021 ◽  
Author(s):  
Anne Karin Magnusson ◽  
Robert Jensen ◽  
Val Swail
Keyword(s):  
Frequency Spectra ◽  
Measurement Systems ◽  
Wave Measurements ◽  
Climate Monitoring ◽  
Production Platform ◽  
Wave Sensors ◽  
Central North Sea ◽  
Wave Forecasting ◽  
Wave Properties

AbstractThe quality of wave measurements is of primary importance for the validation of wave forecasting models, satellite wave calibration and validation, wave physics, offshore operations and design and climate monitoring. Validation of global wave forecasts revealed significant regional differences, which were linked to the different wave buoy systems used by different countries. To fully understand the differences between the wave measurement systems, it is necessary to go beyond investigations of the integral wave parameters height, period and direction, into the frequency spectra and the four directional Fourier parameters that are used to estimate the directional distribution. We here analyse wave data measured from three different sensors (non-directional Datawell Waverider buoy, WaveRadar Rex, Optech laser) operating at the Ekofisk oil production platform located in the central North Sea over a period of several months, with significant wave height ranging from 1 to 10 m. In general, all three sensors provide similar measurements of the integral wave properties and frequency spectra, although there are some significant differences which could impact design and operations, forecast verification and climate monitoring. For example, the radar underestimates energy in frequency bands higher than 8 s by 3–5%, swell (12.5–16 s) by 5–13%, while the laser has 1–2% more energy than the Waverider in the most energetic bands. Lee effects of structures are also estimated. Lower energy at the frequency tail with the radar has an effect on wave periods (they are higher); wave steepness is seen to be reduced by 10% in the wind seas. Goda peakedness and the unidirectional Benjamin-Feir index are also examined for the three sensors.

What's the Buzz? The Neuroscience and the Treatment of Tinnitus

2021 ◽  
Author(s):  
Amanda Henton ◽  
Thanos Tzounopoulos
Keyword(s):  
United States ◽  
The United States ◽  
Global Scale ◽  
Current Treatment ◽  
Public Health Issue ◽  
Current State ◽  
Acquired Hearing Loss ◽  
Neurophysiological Mechanisms ◽  
Necessary And Sufficient

Tinnitus is a pervasive public health issue that affects approximately 15% of the United States population. Similar estimates have also been shown on a global scale, with similar prevalence found in Europe, Asia, and Africa. The severity of tinnitus is heterogeneous, ranging from mildly bothersome to extremely disruptive. In the United States, approximately 10-20% of individuals who experience tinnitus report symptoms that severely reduce their quality of life. Due to the huge personal and societal burden, in the last twenty years a concerted effort on basic and clinical research has significantly advanced our understanding and treatment of this disorder. Yet, neither full understanding, nor cure exists. We know that tinnitus is the persistent involuntary phantom percept of internally-generated non-verbal noises and tones, which in most cases is initiated, by acquired hearing loss and maintained only when this loss is coupled with distinct neuronal changes in auditory and extra-auditory brain networks. Yet, the exact mechanisms and patterns of neural activity that are necessary and sufficient for the perceptual generation and maintenance of tinnitus remain incompletely understood. Combinations of animal model and human research will be essential in filling these gaps. Nevertheless, the existing progress in investigating the neurophysiological mechanisms has improved current treatment and highlighted novel targets for drug development and clinical trials. The aim of this review is to thoroughly discuss the current state of human and animal tinnitus research, outline current challenges, and highlight new and exciting research opportunities.

scholarly journals Features of parasitocenosis in eimeriosis in young ruminants

2021 ◽  
Vol 0 (14) ◽  
pp. 91-100
Author(s):  
Vera Usevich ◽  
N. Kurochkina ◽  
M. Drozd ◽  
Ol'ga Petrova
Keyword(s):  
Comparative Evaluation ◽  
Animal Species ◽  
Treatment Time ◽  
Global Scale ◽  
Laboratory Diagnostics ◽  
Therapeutic Effectiveness ◽  
Treatment And Prevention ◽  
Traditional Remedies ◽  
Eimeria Arloingi

Abstract. The prevalence of coccidiosis diseases of various animal species has a global scale, so this problem has attracted the attention of veterinary specialists around the world. The purpose of this study was to study the specific features of the species composition and laboratory diagnostics of eimeriosis in young ruminants and to evaluate the effectiveness of treatment and prevention when using drugs from different groups. The material for the study was goats and calves. The research was carried out on the basis of two farms of the same agricultural holding in the Sverdlovsk region. Diagnostics was performed based on clinical and laboratory studies. Results of the study. The main pathogens in the goat breeding complex in goats of different ages were identified: the main causative agent of coccidiosis in 120-day-old goats was Eimeria arloingi, which accounted for 54 % of all detected oocysts in the samples. Eimeriosis occurred as a mixed invasion of Eimeria arloingi with Eimeria ninaekohlyakimovae (33 %) and Eimeria intracata (13 %). Eimeria arloingi (68 %), in 21-days-old goats – Eimeria ninaekohlyakimovae (32 %). Eimeriosis caused by Eimeria bovis was detected in 30-days-old calves (100 %). The article describes the results of using various anticoccidial drugs in the treatment and prevention of eimeriosis. A comparative evaluation of the therapeutic effectiveness of known coccidiostatics is given. The economic efficiency of different groups of drugs was evaluated. The scientific novelty lies in the fact that the morphological and quantitative assessment of parasitocenoses in eimeriosis in young ruminants was carried out. A comparative evaluation of the effectiveness of various traditional remedies and a new drug for the treatment of eimeriosis in calves and goats was carried out. Conclusion. Not all of the drugs used have the same therapeutic effectiveness both in terms of treatment time and the quality of elimination of the etiological factor.

scholarly journals Optimal Transmit Volume Conditions for Mission Critical Voice Quality of Experience Measurement Systems

2021 ◽  
Author(s):  
Chelsea Greene ◽  
Jesse Frey ◽  
William Magrogan ◽  
Cara O’Malley ◽  
Jaden Pieper
Keyword(s):  
Quality Of Experience ◽  
Voice Quality ◽  
Measurement Systems ◽  
Mission Critical

scholarly journals Overshooting Americanisation. Accent Stylisation in Pop Singing – Acoustic Properties of the Bath and Trap Vowels in Focus

2017 ◽  
Vol 15 (4) ◽  
pp. 371-384 ◽  
Author(s):  
Monika Konert-Panek
Keyword(s):  
Acoustic Properties ◽  
Phonetic Features

The paper addresses the problem of overshoot involved in singing accent stylisation. Selected phonetic features indexed as “American” and “Cockney” are analysed in the singing and speaking styles of a British vocalist, Adele. Overshoot, understood as a greater frequency or an exaggerated quality of a given feature, is characteristic of staged performance (Bell and Gibson 2011; Coupland 2007). PRAAT is used to establish the acoustic properties (F1 and F2) of the BATH and TRAP vowels, as well as the presence or absence of the BATH-TRAP split. The results show that Americanisation regarding the BATH-TRAP split in singing is present and the Americanised vowel tokens are “overshot”, having higher F2 frequency compared with the regular British TRAP vowel.

scholarly journals Data heterogeneity and oldness, two difficulties to overcome for the world seabed sediment mapping

2021 ◽  
Vol 4 ◽  
pp. 1-7
Author(s):  
Thierry Garlan ◽  
Isabelle Gabelotaud ◽  
Elodie Marchès ◽  
Edith Le Borgne ◽  
Sylvain Lucas
Keyword(s):  
Global Scale ◽  
Single Product ◽  
Seabed Sediment ◽  
Bathymetric Data ◽  
The World ◽  
Data Heterogeneity ◽  
Sediment Data ◽  
The University ◽  
Seabed Sediments

Abstract. A global seabed sediment map has been developed since 1995 to provide a necessary tool for different needs. This project is not completely original since it had already been done in 1912 when the French hydrographic Office and the University of Nancy produced sedimentary maps of the European and North American coasts. Seabed sediments is one of the last geographical domains which can’t benefit of satellite data. Without this contribution, sediment maps need to use very old data mixed with the new ones to be able to reach the goal of a global map. In general, sediment maps are made with the latest available techniques and are replaced after a few decades, thus generating new cartographic works as if all the previous efforts had become useless. Such approach underestimates the quality of past works and prevents to have maps covering large areas. The present work suggests to standardize all kind of sedimentary data from different periods and from very different acquisition systems and integrate them into a single product. This process has already been done for bathymetric data of marine charts, we discuss in this article of the application of this method at a global scale for sediment data.

scholarly journals Las pruebas estandarizadas como forma de medición del nivel de inglés en la educación Colombiana

2020 ◽  
Author(s):  
Jorge Benavides
Keyword(s):  
Standardized Testing ◽  
Field Research ◽  
Foreign Languages ◽  
Measuring Instruments ◽  
Ministry Of Education ◽  
Testing Procedures ◽  
Level Of Knowledge ◽  
To Come ◽  
Globalized World

This article discusses the importance of standardized testing as a means of assessing learning and determining the level of knowledge and use of foreign languages like English. It is very well known that since the second half of the twentieth century efforts were made in order to come up with valid and reliable measuring instruments for linguistic and communicative competence of a person in foreign languages. This began in the area of field research and ongoing reviewing processes to ensure the quality of testing procedures. Today, in a globalized world with many possibilities for mobility of students, teachers, and researchers standardized tests have been popularized and institutionalized in different countries. Colombia has not been the exception and starting from the beginning of this century the Ministry of Education has implemented the standard promoted by the Common European Framework of Reference for Languages which enables standardized measuring levels of English as a foreign language in students, teachers and professionals in general.

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