scholarly journals Quantification of the Absorption and Scattering Effects of Diffusers in a Room with Absorbent Ceiling

Buildings ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 612
Author(s):  
Emma Arvidsson ◽  
Erling Nilsson ◽  
Delphine Bard Hagberg ◽  
Ola J. I. Karlsson
Keyword(s):  
Additional Treatment ◽  
Acoustic Properties ◽  
Configuration Design ◽  
Acoustic Parameters ◽  
Acoustic Action ◽  
Reverberation Chamber ◽  
Laboratory Environment ◽  
Diffusion Characteristics ◽  
Scattering Effects ◽  
The Right

In ordinary public rooms, such as classrooms and offices, an absorbent ceiling is the typical first acoustic action. This treatment provides a good acoustic baseline. However, an improvement of specific room acoustic parameters, operating for specific frequencies, can be needed. It has been seen that diffusing elements can be effective additional treatment. In order to choose the right design, placement, and quantity of diffusers, a model to estimate the effect on the acoustics is necessary. This study evaluated whether an SEA model could be used for that purpose, particularly for the cases where diffusers are used in combination with an absorbent ceiling. It was investigated whether the model could handle different quantities of diffusing elements, varied diffusion characteristics, and varied installation patterns. It was found that the model was sensitive to these changes, given that the output from the model in terms of acoustic properties will be reflected by the change of diffuser configuration design. It was also seen that the absorption and scattering of the diffusers could be quantified in a laboratory environment: a reverberation chamber. Through the SEA model, these quantities could be transformed to a full-scale room for estimation of the room acoustic parameters.

scholarly journals Simulation of sound transmission through the porous material, determining the parameters of acoustic absorption and sound reduction

2018 ◽  
Vol 157 ◽  
pp. 02058
Author(s):  
Peter Zvolenský ◽  
Juraj Grenčík ◽  
Ľubomír Kašiar ◽  
Vladimír Stuchlý
Keyword(s):  
Computer Simulation ◽  
Structural Design ◽  
Internal Noise ◽  
Acoustic Properties ◽  
Acoustic Absorption ◽  
New Materials ◽  
Acoustic Parameters ◽  
Acoustic Comfort ◽  
Sound Reduction

Currently, the quality of structural design of a railway coach is evaluated by so called acoustic comfort, which is characterized by achieved levels of internal noise. Therefore, acoustic parameters of car body are being developed purposely. The paper presents the results of the computer simulation of noise transmission through the wagon walls and the use of noise tests from the train running. The acoustic properties of the original and new materials in the care body are compared.

Acoustic Properties of Timber Joist Ceilings with Respects to their Response onto the Effects of Dynamic Loads

2013 ◽  
Vol 649 ◽  
pp. 269-272 ◽  
Author(s):  
Dagmar Donaťáková ◽  
Jana Krupicová ◽  
Zuzana Kolářová ◽  
Bohumil Straka
Keyword(s):  
Acoustic Properties ◽  
Dynamic Loads ◽  
Subjective Perception ◽  
Acoustic Parameters ◽  
Low Frequencies ◽  
Acoustic Conditions

The paper discusses some issues connected to timber joist ceilings found not only in historical protected buildings but also in newly designed multi-storey timber based ones, with regards to their acoustic parameters perceived by the inhabitants of such objects. These problems are usually connected to the complaints of the users because of unsatisfying acoustic conditions indoors, observed mainly at low frequencies, even though the requirements given by the legislation are met. The paper with its content is a reaction to the contradiction between the results coming from measurements and subjective perception, and is complemented by structural evaluations seeking the effects of dynamic tremors and vibrations.

scholarly journals Medial compartment disease in a young Large Munsterlander

2012 ◽  
Vol 81 (2) ◽  
pp. 88-92
Author(s):  
E. Coppieters ◽  
Y. Samoy ◽  
P. Pey ◽  
T. Waelbers ◽  
B. Van Ryssen
Keyword(s):  
Elbow Joint ◽  
Substantial Improvement ◽  
Additional Treatment ◽  
Coronoid Process ◽  
Medial Compartment ◽  
Radiographic Examination ◽  
Arthroscopic Examination ◽  
The Right ◽  
Humeral Condyle ◽  
Strong Suspicion

Medial compartment disease (MCD) is a recently recognized elbow disorder in dogs and refers to extensive cartilage erosions of the medial compartment of the elbow joint. This report describes a case of MCD in a 10- month-old Large Munsterlander that was presented with right frontleg lameness. Based on signalement, history and radiographic examination, there was a strong suspicion of a fragmented coronoid process (FCP) of the right elbow. However, arthroscopic examination revealed extensive cartilage erosions of the medial part of the humeral condyle and the medial coronoid process in addition to a small coronoid fragment (FCP) and a small OCD-like lesion. After the arthroscopic treatment, the dog did not improve. Neither did additional treatment with autologous conditioned plasma (Arthrex ACP®) lead to a substantial improvement. Finally, the dog was euthanized because of persistent lameness.

scholarly journals Trajectories of Mother-Infant Communication: An Experiential Measure of the Impacts of Early Life Adversity

2021 ◽  
Vol 15 ◽  
Author(s):  
Lauren Granata ◽  
Alissa Valentine ◽  
Jason L. Hirsch ◽  
Jennifer Honeycutt ◽  
Heather Brenhouse
Keyword(s):  
Maternal Care ◽  
Early Life ◽  
Maternal Separation ◽  
Developmental Trajectories ◽  
Later Life ◽  
Developmental Trajectory ◽  
Acoustic Properties ◽  
Emission Rates ◽  
Acoustic Parameters ◽  
Early Life Adversity

Caretaking stability in the early life environment supports neurobehavioral development, while instability and neglect constitute adverse environments that can alter maturational processes. Research in humans suggests that different types of early life adversity (ELA) can have differential effects on caretaker relationships and later cognitive and social development; however, identifying mechanistic underpinnings will require animal models with translational validity. Two common rodent models, maternal separation (MS) and limited bedding (LB), influence the mother-infant relationship during a critical window of development. We hypothesized that these paradigms may affect the development of communication strategies on the part of the pup. Ultrasonic vocalizations (USVs) are a care-eliciting mechanism and ethologically relevant response to stressors in the rat pup. USV emission rates and acoustic parameters change throughout early development, presenting the opportunity to define developmental milestones in USVs that would reflect neurobehavioral aberrations if disrupted. This study investigated the effects of MS or LB on the dam-pup relationship by quantifying pup USVs, maternal behavior, and the relationship between the two. First, we used a generalized additive model approach to establish typical developmental trajectories of USV acoustic properties and determine windows of change in MS or LB rearing. Additionally, we quantified maternal behaviors and the predictability of maternal care sequences using an entropy rate calculation. MS and LB each shifted the developmental trajectories of USV acoustic parameters and call types in a sex-specific manner. MS more often impacted male USVs, while LB impacted female USVs. MS dams spent more time passive nursing, and LB dams spent more time on the nest. The predictability of maternal care was associated with the rate of USV emissions exclusively in females. Taken together, findings demonstrate sex- and model-specific effects of rearing environments on a novel developmental trajectory involving the mother-infant relationship, facilitating the translation of animal ELA paradigms to assess later-life consequences.

scholarly journals An Exploratory Study on the Acoustic Musical Properties to Decrease Self-Perceived Anxiety

2022 ◽  
Vol 19 (2) ◽  
pp. 994
Author(s):  
Emilia Parada-Cabaleiro ◽  
Anton Batliner ◽  
Markus Schedl
Keyword(s):  
Exploratory Study ◽  
User Study ◽  
Acoustic Properties ◽  
Musical Work ◽  
State Trait Anxiety Inventory ◽  
Tonal Music ◽  
Acoustic Parameters ◽  
Positive Statements ◽  
Musical Listening

Musical listening is broadly used as an inexpensive and safe method to reduce self-perceived anxiety. This strategy is based on the emotivist assumption claiming that emotions are not only recognised in music but induced by it. Yet, the acoustic properties of musical work capable of reducing anxiety are still under-researched. To fill this gap, we explore whether the acoustic parameters relevant in music emotion recognition are also suitable to identify music with relaxing properties. As an anxiety indicator, the positive statements from the six-item Spielberger State-Trait Anxiety Inventory, a self-reported score from 3 to 12, are taken. A user-study with 50 participants assessing the relaxing potential of four musical pieces was conducted; subsequently, the acoustic parameters were evaluated. Our study shows that when using classical Western music to reduce self-perceived anxiety, tonal music should be considered. In addition, it also indicates that harmonicity is a suitable indicator of relaxing music, while the role of scoring and dynamics in reducing non-pathological listener distress should be further investigated.

scholarly journals Ultrasonic measurement of blubber thickness in right whales

2020 ◽  
pp. 301-309
Author(s):  
M. J. Moore ◽  
C.A. Miller ◽  
R. Arthur ◽  
W.A. Lange ◽  
K.G. Prada ◽  
...  
Keyword(s):  
Body Condition ◽  
Repeated Measures ◽  
Field Measurements ◽  
The Body ◽  
Acoustic Properties ◽  
Right Whale ◽  
Adult Growth ◽  
Right Whales ◽  
Connective Tissue Sheath ◽  
The Right

The right whale population in the northwestern Atlantic appears to face the risk of extinction: ship and fishing gear trauma are significantmortality factors, but calving rates are also depressed compared to southern right whales. A major factor in calving success in many speciesis body condition. Knowledge of the dynamics of body condition is also important in studies of juvenile and sub-adult growth and seasonalchanges in adults. This paper describes a method to assess body condition in live right whales. To characterise the acoustic properties ofthe blubber/muscle interface we first studied samples of Atlantic white-sided dolphin and right whale in the laboratory. Tissue heterogeneitywas examined grossly and in histological sections. Acoustic echoes were strong from the sub-dermal connective tissue sheath(s). Echostrengths did not appear to vary with lipid content. We then used a 0.5MHz ultrasound transducer on a cantilevered 12m pole to touch theback of surfacing right whales briefly. Multiple laboratory and field measurements on individual animals suggest repeated measures ofblubber thickness at a single location are reasonably consistent. Data will be normalised to both sampling position on the body and to lengthof the animal, estimated by mensuration from stereo video images of the animal during sampling. In this way, using a long-term consistentdatabase of blubber thickness measurements, and catalogued reproductive histories from on-going photographic identification studies, weplan to assess the significance of changing body condition in right whale population dynamics.

scholarly journals Therapeutic Options for Chronic Rhinosinusitis in N-ERD Patients

2021 ◽  
Vol 2 ◽  
Author(s):  
Rik J. L. van der Lans ◽  
Wytske J. Fokkens ◽  
Sietze Reitsma
Keyword(s):  
Chronic Rhinosinusitis ◽  
Treatment Options ◽  
Additional Treatment ◽  
Aspirin Therapy ◽  
Sinus Surgery ◽  
Shared Decision ◽  
Diffuse Type ◽  
Treatment Resistant ◽  
The Right

Patients with non-steroidal anti-inflammatory drug (NSAID)-exacerbated respiratory disease (N-ERD) often suffer from chronic rhinosinusitis (CRS) with nasal polyps, a form of primary diffuse Type 2 CRS. Although this disease is also seen in NSAID-tolerant patients, CRS in N-ERD often is more severe and more treatment resistant; local nasal therapy (nasal corticosteroids) and endoscopic sinus surgery are employed like in NSAID-tolerant patients, but with limited and/or short-lived effects. This mini-review gives an overview of the current additional treatment options for CRS in N-ERD. As such diets, aspirin therapy after desensitization, antileukotriene therapy and biologicals are discussed based on the current body of literature. Selecting the right treatment strategy depends on shared-decision making, local availability and cooperation between ENT-surgeons, allergists, and pulmonologists.

scholarly journals Acoustic impedance measurement of snow density

1998 ◽  
Vol 26 ◽  
pp. 92-96 ◽  
Author(s):  
O. Marco ◽  
O. Buser ◽  
P. Villemain ◽  
F. Touvier ◽  
Ph. Revol
Keyword(s):  
Porous Media ◽  
Acoustic Wave ◽  
Gamma Rays ◽  
Electromagnetic Waves ◽  
Characteristic Impedance ◽  
Impedance Measurement ◽  
Acoustic Properties ◽  
Laboratory Measurements ◽  
Snow Density ◽  
Acoustic Parameters

Today, it is possible to estimate the density of snow in many different ways (gravimetry, attenuation of gamma rays and velocity of electromagnetic waves). In this paper, we suggest using the acoustic properties of snow. First, we recall the main studies on the acoustic properties of snow. Then, we show, from laboratory measurements, the correlation between density and the acoustic parameters of snow. We found a very good correlation between density and the modulus of the normalized characteristic impedance. We also show that use ofa three-parameter model simulating the propagation of an acoustic wave in porous media allows one to calculate the density of snow from its acoustic porosity.

scholarly journals Acoustic impedance measurement of snow density

1998 ◽  
Vol 26 ◽  
pp. 92-96 ◽  
Author(s):  
O. Marco ◽  
O. Buser ◽  
P. Villemain ◽  
F. Touvier ◽  
Ph. Revol
Keyword(s):  
Porous Media ◽  
Acoustic Wave ◽  
Gamma Rays ◽  
Electromagnetic Waves ◽  
Characteristic Impedance ◽  
Impedance Measurement ◽  
Acoustic Properties ◽  
Laboratory Measurements ◽  
Snow Density ◽  
Acoustic Parameters

Today, it is possible to estimate the density of snow in many different ways (gravimetry, attenuation of gamma rays and velocity of electromagnetic waves). In this paper, we suggest using the acoustic properties of snow. First, we recall the main studies on the acoustic properties of snow. Then, we show, from laboratory measurements, the correlation between density and the acoustic parameters of snow. We found a very good correlation between density and the modulus of the normalized characteristic impedance. We also show that use ofa three-parameter model simulating the propagation of an acoustic wave in porous media allows one to calculate the density of snow from its acoustic porosity.

Active Acoustic Systems for the Control of Room Acoustics

2011 ◽  
Vol 18 (3-4) ◽  
pp. 237-258 ◽  
Author(s):  
M. A. Poletti
Keyword(s):  
Subjective Experience ◽  
Sound Field ◽  
Acoustic Properties ◽  
Room Acoustics ◽  
Live Performance ◽  
Acoustic Parameters ◽  
Active Systems ◽  
Acoustic Design ◽  
Boundary Properties ◽  
Passive Acoustic

The acoustic design of auditoria involves the specification of the room geometry and boundary properties, and any additional acoustic elements such as reflectors or diffusers, to usefully direct sound to produce a desired subjective experience, quantified by measurable acoustic parameters. This design must take into account the reflection of sound within the stage area, the early reflections from the stage to the audience and the reverberant response of the room. The sound produced by the audience can also be an important consideration. Active acoustic systems provide an alternative approach to controlling subjective experience. They use microphones, electronic processors and loudspeakers to create reflections and reverberation in addition to those produced by the naturally-occurring sound field. The acoustic properties can be changed instantly, and the enhanced acoustic properties of the auditorium can typically be varied over a wider range than can be produced by variable passive techniques. The design of active acoustics follows that of passive approaches, but rather than the physical arrangement of the room surfaces, it commences with an existing passive space with some minimum acoustic condition, and requires the arrangement of microphones to detect relevant sound and the choice of processors and loudspeaker positions to direct it usefully back into the room to produce a desired set of acoustic parameters. While active systems have historically been developed with the goal of enhancing either the stage or audience sound, they must generally provide the same control of sound as passive acoustic design. This paper discusses the principles of active acoustic systems and how they are used to achieve the required range of control. A survey of current commercial systems is given and some implications for the future of live performance are explored.

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