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The Skinny on Artificial Intelligence

It seems every week there is report of yet another advancement in artificial intelligence (AI), each replicating or exceeding some  ability once deemed the exclusive domain of human intellect. It is touted in the popular media that self-driving cars will soon become the norm, as computer controlled auto-pilots are safer than human drivers. Even hearing…
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Multi-dimensional Pitch – A Moving Target

When referring to pitch, we think about how high or low a note is on  a relative scale. Pitch is an acoustic carrier of meaning, as the different phonemes of speech and the overall intonation of voice is denoted by changes in pitch. Melody is also made possible by pitch modulation. Aside from emotional and…
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Psycho-acoustics – A Very Human Perspective of Sound

Your ear is an amazing piece of engineering. It converts vibrations in the air into meaningful perception. As sound travels along the auditory pathways it is converted into three different forms of energy (mechanical, hydraulic and neuro-chemical) before it is actually heard. By physical definition, sound is a repeating molecular disturbance that propagates in all…
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Infra-sonic Sound – Rumblings Between the Centre and Fringes of Science

As far as physical phenomena go, infrasound has probably been implicated in more mysterious events than just about anything else on the planet. From ghost sightings and sleep deprivation, to a sense of impending doom, infrasound has been offered as an explanation for a myriad of strange occurrences. In terms of pure physics, there is…
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The Bizarre World of Acoustic Levitation

Normally when we hear the word levitation, we associate it with the art of illusion or electro-magnetism. We know that some high speed trains float at incredible speeds with the assistance of electro-magnetic levitation.  It seems less probable to associate levitation with soundwaves. Acoustic levitation is real however, and it is used by high tech industry…
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Otic Barotrauma – Flyers and Divers Beware!

At one time or another, most people will experience the discomfort caused by not being able to ‘pop’ one’s ears during an aircraft descent. When air pressure in the space behind the eardrum (the middle ear) is not maintained at atmospheric pressure, tension is placed on the eardrum. It is the job of the Eustachian tubes…
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Human Voice – A Unique Identifier

It is uncanny how we can recognize an individual’s voice from a million other voices. A person’s voice is as unique as a fingerprint. In fact, no two voices on the planet are identical. Voice characteristics are dependent on a number of anatomical factors, including: size and strength of the lungs, dimension of the airways…
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Otoacoustic Emissions – Mysterious Ear Echoes

How did the discovery of mysterious echoes emanating from the inner ear finally vindicate an English physicist 40 years later? During the 1600s early theories of hearing accepted that the ear  (specifically the cochlea) was  a passive receptor of sound. Essentially the cochlea was believed to be a kind of complex resonator, over which environmental inputs…
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Beetles And Bats: An Evolutionary Arms-Race!

The common beetle may have the unenviable title of being “deaf as”, but it turns out it may not be entirely unjustified. There are approximately 400,000 species of beetle described in the literature and probably a few million more yet to be documented. Beetles constitute almost 25 percent of all living creatures on earth. Despite…
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Can You Hear In Space?

Last week we looked at the unnerving effects of being deprived of external sounds in an anechoic chamber. Bodily noises take centre stage as our brains hunt for sound. The environment begins to close in upon us without the reassuring presence of low level ambient noise. Of course not everybody finds the sound sterile environment…
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