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Noise Monitoring for your home, Thailand

 

The first DIY noise monitoring, easy to use and install, just plug in the power, wifi and ready to go, online data noise monitoring, accurate, calibrated, weatherproof. Automated alarms by email or messenger.

Noisy neighbours, noise from entertainment or from a factory, road noise?

Register the noise and discuss with the authorities how to resolve the issue.

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Noise Nuisance Monitoring Thailand Noise Nuisance Monitoring Thailand, Malaysia, Indonesia, Vietnam

 
 
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Asia Noise News

Soundscape Under Covid-19

Many around the world are experiencing life with very low noise levels due to restrictions as we are confined to our home and there is a decrease in the industrial, transportation and leisure activity. This provides a wonderful opportunity to quantify and record for the future the lower noise levels of our soundscapes. With the reduction in shipping there is also a change in the underwater soundscapes.

Nowadays there are a high number of noise monitoring systems (noise monitoring terminals, city wide systems, underwater systems etc.) installed all over the world which will capture this information for the future. However, there are many acousticians working from home with access to a sound level meter that can be used to capture the soundscape from their balcony or from their garden and compare the before and after the restrictions.

The IYS 2020 committee has provided a central contact between a number around the world who were thinking similarly that there would be some benefit in coordination and a little standardization in the capture of the data. Marçal Serra from CESVA has taken a lead to set up a LinkedIn group COVID-19 Noise Reduction (at www.linkedin.com/groups/13844820/) and with hashtag #COVID19NoiseReduction for any posts.

The following is a general structure for those who wish to participate and share their data in the future. But do not break your confinement to report this data!

  • Place: Country and city (e.g., Spain village near Barcelona)
  • Primary noise source: (e.g., Traffic noise: note number of lanes per direction or Social noise: note if café/bar/restaurant/sporting)
  • Noise measuring system: The noise measuring system used to measure LduringLbefore, and Lafter
  • Noise level during COVID-19 confinement: Lduring, expressed as a weighted overall level (preferably LAeq,1 hour), spectrum or psychoacoustic metrics as Loudness. It could also be reported as an image of the noise time history or a weekly color map and/or compiled into a report/article/conference paper with the measurement details and the comparison data
  • Noise level before & after COVID-19 confinement: Lbefore & Lafter, expressed in the same way as Lduring and over the same time period.
Categories
Asia Noise News

Human Hearing

Binaural hearing allows for localizing the source of the sound, suppressing noise, example to better understand speech. To localize sound there is an important aspect of auditory perception that allows us to adjust to the room, namely spatial hearing. There are two processes in localizing sounds in humans, monaural cues and different cues.

  • Monaural Cues

Monaural cues are how each ear translates the captured sound signal. Monaural cues are the result of a convolution of sound sources with head-related transfer function (HRTF) impulses. Head-Related Transfer Function (HRTFs) is a form of transformation of sound wave propagation from the source to the ear or Head-Related Impulse Response (HRIR). HRTF is also defined as a form of modification of a sound from a certain direction that reaches the ear. This transformation involves diffraction and reflection from the anatomy of the ear. HRTF also depends on the location of the sound source relative to the listener so that it can determine the sound source.

  • Difference Cues

Difference cues are how the difference between two ears translates to sound signals. These differences cues contain information on International Time Difference (ITD) and Interaural Level Difference (ILD). ITD is the difference in the arrival time of the left and right ear sound waves while ILD is the difference in pressure level between the left and right ears. Based on Duplex Theory, ITD values ​​are used for localizing sounds at low frequencies, which is below 1.5 kHz while ILD is used for localizing sounds at high frequencies, which is above 1.5 kHz. Environmental sounds are in the range of low frequency and high frequency so that the human auditory system uses ITD and ILD.

The basic principles in ITD are illustrated in Figure 1

Figure 1 Interaural Time Difference (ITD) principal

When the sound source is sound waves with low frequency, the propagation of sound waves will reach both ears without decreasing the sound pressure level. This is because the wavelength of sound is smaller than the dimensions of the head. However, there is a time difference received between the two ears. Therefore, sound waves at low frequencies are related to ITD.

The basic principles of ILD are illustrated in Figure 2. The ILD value is influenced by the size of the head and for sources that are very close to the head. When the sound source is in the high-frequency range where the wavelength of the sound is smaller than the dimensions of the head, the sound will reach the ears closer to the sound source. When will reach the other ear, the sound will be held up or there is a failure of propagation of sound waves for a while, this phenomenon is called an acoustic shadow. The sound that finally reaches the other ear will experience a decrease in the level of sound pressure caused by the phenomenon of acoustic shadow.

Figure 2. Acoustic shadow phenomenon at high frequency

Written by:

Adetia Alfadenata

Acoustic Engineer

Geonoise Indonesia

support.id@geonoise.asia

Reference

  1. T. Potisk, “Head-Related Transfer Function,” 2015.
  2. X. Zhong and B. Xie, “Head-Related Transfer Functions and Virtual Auditory Display,” Soundscape Semiot. – Localis. Categ., 2014
  3. W. György, “HRTFs in Human Localization : Measurement , Spectral Evaluation and Practical Use in Virtual Audio Environment,” 2002.
  4. K. Carlsson, “Objective Localisation Measures in Ambisonic Surround- sound,” 2004.
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Asia Noise News

Ultrasound Selectively Damages Cancer Cells When Tuned to Correct Frequencies

Doctors have used focused ultrasound to destroy tumors in the body without invasive surgery for some time. However, the therapeutic ultrasound used in clinics today indiscriminately damages cancer and healthy cells alike.

Most forms of ultrasound-based therapies either use high-intensity beams to heat and destroy cells or special contrast agents that are injected prior to ultrasound, which can shatter nearby cells. Heat can harm healthy cells as well as cancer cells, and contrast agents only work for a minority of tumors.

Researchers at the California Institute of Technology and City of Hope Beckman Research Institute have developed a low-intensity ultrasound approach that exploits the unique physical and structural properties of tumor cells to target them and provide a more selective, safer option. By scaling down the intensity and carefully tuning the frequency to match the target cells, the group was able to break apart several types of cancer cells without harming healthy blood cells.Their findings, reported in Applied Physics Letters, from AIP Publishing, are a new step in the emerging field called oncotripsy, the singling out and killing of cancer cells based on their physical properties.

Targeted pulsed ultrasound takes advantage of the unique mechanical properties of cancer cells to destroy them while sparing healthy cells.

“This project shows that ultrasound can be used to target cancer cells based on their mechanical properties,” said David Mittelstein, lead author on the paper. “This is an exciting proof of concept for a new kind of cancer therapy that doesn’t require the cancer to have unique molecular markers or to be located separately from healthy cells to be targeted.”

A solid mechanics lab at Caltech first developed the theory of oncotripsy, based on the idea that cells are vulnerable to ultrasound at specific frequencies — like how a trained singer can shatter a wine glass by singing a specific note.

The Caltech team found at certain frequencies, low-intensity ultrasound caused the cellular skeleton of cancer cells to break down, while nearby healthy cells were unscathed.

“Just by tuning the frequency of stimulation, we saw a dramatic difference in how cancer and healthy cells responded,” Mittelstein said. “There are many questions left to investigate about the precise mechanism, but our findings are very encouraging.”The researchers hope their work will inspire others to explore oncotripsy as a treatment that could one day be used alongside chemotherapy, immunotherapy, radiation and surgery. They plan to gain a better understanding of what specifically occurs in a cell impacted by this form of ultrasound.

Written by:

Phawin Phanudom (Gun)
Acoustical Engineer

Geonoise (Thailand) Co., Ltd.
Tel: +6621214399
Mobile: +66891089797
Web: https://geonoise.com//
Email: phawin@geonoise.asia

Credit: Publishing AIP

Categories
Asia Noise News

Dogs Can Experience Hearing Loss

Just like humans, dogs are sometimes born with impaired hearing or experience hearing loss as a result of disease, inflammation, aging or exposure to noise. Dog owners and K-9 handlers ought to keep this in mind when adopting or caring for dogs, and when bringing them into noisy environments, says Dr. Kari Foss, a veterinary neurologist and professor of veterinary clinical medicine at the University of Illinois at Urbana-Champaign.

In a new report in the journal Topics in Companion Animal Medicine, Foss and her colleagues describe cases of hearing loss in three working dogs: a gundog, a sniffer dog and a police dog. One of the three had permanent hearing loss, one responded to treatment and the third did not return to the facility where it was originally diagnosed for follow-up care.

The case studies demonstrate that those who work with police or hunting dogs “should be aware of a dog’s proximity to gunfire and potentially consider hearing protection,” Foss said. Several types of hearing protection for dogs are available commercially.

Just as in humans, loud noises can harm the delicate structures of a dog’s middle and inner ear.

“Most commonly, noise-induced hearing loss results from damage to the hair cells in the cochlea that vibrate in response to sound waves,” Foss said. “However, extreme noise may also damage the eardrum and the small bones within the inner ear, called the ossicles.”

Pet owners or dog handlers tend to notice when an animal stops responding to sounds or commands. However, it is easy to miss the signs, especially in dogs with one or more canine companions, Foss said.

“In puppies with congenital deafness, signs may not be noticed until the puppy is removed from the litter,” she said.

Signs of hearing loss in dogs include failing to respond when called, sleeping through sounds that normally would rouse them, startling at loud noises that previously didn’t bother them, barking excessively or making unusual vocal sounds, Foss said. Dogs with deafness in one ear might respond to commands but could have difficulty locating the source of a sound.

If pet owners think their pet is experiencing hearing loss, they should have the animal assessed by a veterinarian, Foss said. Hearing loss that stems from ear infections, inflammation or polyps in the middle ear can be treated and, in many cases, resolved.

Hearing-impaired or deaf dogs may miss clues about potential threats in their surroundings, Foss said.

“They are vulnerable to undetected dangers such as motor vehicles or predators and therefore should be monitored when outside,” she said.

If the hearing loss is permanent, dog owners can find ways to adapt, Foss said.

“Owners can use eye contact, facial expressions and hand signals to communicate with their pets,” she said. “Treats, toy rewards and affection will keep dogs interested in their training.” Blinking lights can be used to signal a pet to come inside.

Hearing loss does not appear to affect dogs’ quality of life, Foss said.”A dog with congenital hearing loss grows up completely unaware that they are any different from other dogs,” she said. “Dogs that lose their hearing later in life may be more acutely aware of their hearing loss, but they adapt quite well. A dog’s life would be significantly more affected by the loss of smell than by a loss of hearing.”

Written by:

Pitupong Sarapho (Pond)
Acoustical Engineer

Geonoise (Thailand) Co., Ltd.
Tel: +6621214399
Mobile: +66868961299
Email: pond@geonoise.asia

Credit: Diana Yates, University of Illinois at Urbana-Champaign

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