mentions noise, we all know that it is harmful to the human body, and noise over 50 decibels will affect sleep and rest. Due to insufficient rest and fatigue cannot be eliminated, normal physiological functions will be affected to a certain extent. More than 70 decibels will interfere with the conversation, cause distraction, affect work efficiency, and even cause accidents. Working or living in a noise environment above 90 decibels for a long time will seriously affect hearing and lead to the occurrence of other diseases. So is there a beneficial side to noise? The answer is yes.
Noise is useless. New research shows that noise can become useful after being technically processed, becoming a pioneer technology and even making us smarter. Why is this?
| The benefits of noise to humans
1, train neural cells
WHO defines noise as "any sound you don't want to hear". Spanish law sets the standard of 35 decibels during the day and 30 decibels at night as a comfortable indoor sound environment. Other studies have set the appropriate sound environment standard between 50 and 65 decibels, and continuous sounds outside this range can make people feel unpleasant. However, the standard of comfortable volume depends on your personal subjective feeling. The sound of the rock concert is above 120 decibels, but it is very satisfying for heavy metal music hobbies. In addition, Bart Koshko, a professor in the Department of Electronics at the University of Southern California, pointed out that a volume slightly lower than a guitar sound is good for the brain. "Imagine you're in a crowded bar, and when you're trying to talk to friends, music and vocals can hinder your communication." These noises are boring, but they are good over time. "Noise forces us to concentrate, and the brain must use more nerve cells than usual, and as a result, our thinking becomes more agile. The sound environment is conducive to driving away the inertia of thought and training our brain."
Writer Isaac Asimov did not know Professor Koshko, but he unknowingly put his theory into practice. Asimov cannot work without background sound, so he recorded various noises such as ground tremors and traffic sounds, playing exciting inspiration while writing his own book.
There are also many young people who are listening to music to learn, and their concentration will not be affected.
2, random resonance
biology experts from the University of New Orleans conducted research on a fish feeding on plankton in the Mississippi river. The fish does not use vision or smell to prey, but uses an organ on the body that reacts when it comes into contact with the electric field of plankton. The waves of the electric field of plankton are linear and have no fluctuations, but researchers use sound to interfere with the electric field. The sound waves disrupt the original linear waves of the electric field. Scientists think this will make it difficult for fish to find food again, but the result is the opposite. Due to the intervention of noise, the fish become more flexible and eat more plankton.
The reason for this fish's tactile system is very sensitive to so-called random resonance. Physicists use random resonance to describe the phenomenon that some degree of interference is conducive to or even improves final signal reception. This principle may be the same for humans. Alex Purger, a professor of human brain and cognitive science at the University of Rochester in the United States, explained that nerve cells in the cerebral cortex emit chaotic electronic signals, which are called "nerve noise." When these nerve cells receive external sound stimulation, the nerve noise emitted will increase. But this will not cause brain confusion, but will instead make your thinking more agile. Pure believes that it is an evolutionary mechanism that helps humans not get lost in the noisy world. He explained: "It's like if nerve cells know that we live in a world of noise, in order to achieve maximum productivity, they need to receive signals of this noise."
3. Improve learning ability
Researchers from Edithcow University in Australia have studied the effects of "transcranial random noise stimulation" (TRNS) in various environments and found that the technology may have many uses.Technically processed "noise" can help some people improve their learning potential.
Random noise stimulation technology (TRNS) involves applying any form of energy (such as light, mechanical, electrical, sound) to the brain or sensory receptors at unpredictable intensity over time to enhance sensory, motor or cognitive function. There is evidence that transcranial random noise stimulation can increase corticospinal excitability, improve cognitive, motor performance, and have beneficial effects on behavioral and psychological levels. Random noise stimulation can treat neurological diseases, including attention deficit hyperactivity disorder, schizophrenia , amblyopia , myopia, tinnitus , multiple sclerosis and loss of sensitivity. "This technology is promising in improving learning ability, it can speed up learning and help people with neurological diseases, for example, people with learning difficulties can use it to improve learning efficiency. If such stimulation is applied during the learning process, people will perform better, learn faster, and focus more."
| The benefits of noise to life
1. Generate power with noise
Noise is an energy pollution. For example, the sound power of jet aircraft with noise reaches 160dB is about 10000W; the sound power of large blowers with noise reaches 140dB is about 100W. "Gathering sand can make a tower", which naturally arouses the interest of new energy developers. Scientists have discovered that artificial lithium niobate has a special function of converting acoustic energy into electrical energy at high frequency and high temperatures. Scientists also found that when sound waves encounter a barrier, acoustic energy will be converted into electrical energy. British scholars designed and manufactured tympanic membrane acoustic wave receiver based on this principle, connecting the receiver to a resonator that can increase sound energy and accumulate energy. When the acoustic energy from the resonator acts on the acousto-electric converter, electricity can be emitted.
2. Use noise to cool
The refrigerator can cool. But it is encouraging that a new refrigeration technology, , is currently developing in the world, that is, to use weak acoustic vibrations to cool. The first prototype has been successfully trial-made in the United States. In a cylinder with an extremely simple structure, with a diameter of less than 1 meter, there are several fiberglass board that serves as heat transfer, and the cylinder is filled with helium or other gases. One end of the cylinder is sealed and the other end is sealed with an elastic diaphragm. A wire on the diaphragm is connected to a magnet voice coil to form a micro microphone. The sound waves act on the diaphragm, causing back and forth to vibrate, and thus changing the pressure of the gas in the cylinder. Since the gas becomes hot when compressed and cools when expanded, refrigeration begins. It is not difficult to imagine that if these factors can be considered in the future, residential, factory and other buildings can reduce the invisible harm of noise in one fell swoop and cool down the residential, factory and other buildings.
3. The three noise reduction measures commonly used by using noise to actively abolish
, namely, noise reduction at the sound source, noise reduction during the propagation process, and noise reduction in the human ear, are all negative and passive. In order to actively eliminate noise, people invented the technology of "active sound silence". Its principle is: all sounds are composed of a certain frequency spectrum. If you can find a sound, its frequency spectrum is exactly the same as the noise to be eliminated, except that the phase is just the opposite (180° difference), the noise can be completely cancelled. The key is how to get the noise-repellent sound. The actual method is to start from the noise source itself and try to reverse the phase of the original noise through the electronic circuit. From this point of view, the technology of active sound silencing is actually "to fight poison with poison."
(pictures are from the Internet)
