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Audio surveillance, video surveillance. Schemes, articles, descriptions

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Audio surveillance, video surveillance

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Solar collectors. Space heating

Section Alternative energy sources. An active solar heating system can not only provide hot water, but also additional heating via a district heating system. To ensure the performance of such a system, the temperature of the central heating must be kept to a minimum (preferably around 50°C), and it is also necessary to store heat for heating. A successful solution is the combination of a solar heating system with floor heating, in which the floor acts as a heat accumulator. Solar installations for space heating are less profitable than water heaters from both an economic and energy point of view, since heating is rarely needed in the summer. But if you need to heat rooms in summer (for example, in mountainous areas), then heating installations become profitable ... >>

Protection of equipment against power surges up to 160 and over 250 volts

Section Protection of equipment from emergency operation of the network, uninterruptible power supplies. A device for protecting equipment from power surges is proposed. Unlike those described earlier, the proposed device does not turn on again when the normal mains voltage is restored. Switching on occurs only after pressing the 'ON' button. This is necessary when the equipment is turned on unattended, and the mains at this time begins to jump or turn off repeatedly ... >>

Digital Ad Dispenser

Section Television. A modern person is surrounded by advertising on all sides every day, and the more optimally the flow of information flowing at us from all sides is regulated, the sooner we will be able to treat it as an inevitable source of information - a guide to action when making purchases or receiving certain services. Many entrepreneurs have already felt a tangible effect from the information that regularly appears in the media advertising their products and services. An additional effect can be provided by local advertising that meets the client at the doorstep of your office or store. This can be short (1...16 seconds) audio or video information, launched automatically when the front door (or elevator door) is opened, and not repeated more often than the period of time you set, in order to avoid getting boring. Digital advertising dispenser (hereinafter simply DAD) is a device for launching an advertising message and regulating the duration of the pause after it, during which re-launch of advertising is not possible ... >>

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Articles on audio surveillance, video surveillance

Articles on audio and video surveillance; audio and video surveillance schemes; descriptions of audio and video surveillance: 15 articles



All articles on security devices



Latest news of science and technology, new electronics:

Blinking of the magician and his audience 19.05.2024

Magic and illusions have always captured the attention of the public, but what happens behind the scenes of the magician and in the brains of his audience? Scientists from the UK decided to solve this mystery by conducting a new study involving ten illusionists of varying experience. Illusionists, some of whom had been practicing magic for more than half a century, others for only six months, were invited to demonstrate the same trick - the popular coin trick. Recordings of their performances during training and on stage showed that each of them began to blink significantly more often at the moment of performing the trick. The study's findings indicate that magicians' blink rate may be related to unconscious aspects of their performance. At the same time, as scientists have found, spectators also begin to blink more often, following the movements of the illusionist. This observation supports the idea that magicians may be catalysts for blinking in audiences. Additional research has shown that magicians blink more often during ... >>

Ultrasonic coffee machine 19.05.2024

Iced coffee has become an integral part of coffee culture in recent years. Therefore, engineers from the University of New South Wales decided to improve its preparation. They have developed an ultrasonic coffee machine that reduces the cold brew time for ground coffee beans from 12-24 hours to significantly less time. Iced coffee, or "Cold brew", is popular due to its smoothness, low acidity and low bitterness. It is prepared by steeping ground coffee in cold water for a long time. Unlike traditional hot brewing, which often imparts bitterness to coffee, cold brewing extracts more delicate and complex flavors from the coffee beans. The innovative system, presented by a team of engineers, introduces ultrasonic technology into the coffee preparation process. The system uses ultrasonic waves to speed up the process of extracting oils, flavor and aroma from ground coffee. This allows you to significantly reduce the time ... >>

The speech of sperm whales is similar to that of humans 18.05.2024

In the world of the ocean, where the mysterious and unknown coexists with the studied, sperm whales, with their huge brains, are of particular interest to science. Researchers, working with a huge array of audio recordings collected during the Dominica Sperm Whale Project (DSWP) - more than 8000 recordings, seek to unravel the secrets of their communication and understand the structure and complexity of the language of these mysterious creatures. By studying in detail the recordings of 60 sperm whales in the eastern Caribbean, scientists have revealed surprising features of their communication, revealing the complexity of their language. "Our observations indicate that these whales have a highly developed combinatorial communication system, including rubato and ornaments, which indicates their ability to quickly adapt and vary during communication. Despite significant differences in evolution, sperm whales have elements in their communication that are characteristic of human communication," says Shane Gero, a biologist at Carleton University and director of the CETI project. Issl ... >>

Random news from the Archive

Smart bracelet will track the composition of sweat 07.02.2016

The new portable sweat analyzer can detect four types of chemicals at once and measure body temperature at the same time.

Our visit to the doctor most often begins with a blood test. No doubt, blood is an excellent indicator of the state of health, and the further, the more diseases can be recognized by the composition of various cells and molecules floating in the bloodstream.

But we have another biological fluid in which a lot of biochemical information can also be found - this is sweat. In addition to water and simple ions, it also contains complex biomolecules, up to proteins, and even now sweat analysis allows diagnosing certain diseases, finding out what substances a person has taken, choosing a convenient exercise regimen, etc. In addition, sweat has one important advantage - for it you do not need to poke something sharp into a finger or a vein. However, until now, in order to make an analysis of sweat, it had to be collected in a special container in order to then give it to a specialist.

With a new device developed by the staff of the University of California at Berkeley, everything will become faster and easier - Wei Gao (Wei Gao) and colleagues have created an electronic analyzer that can be worn on the arm like a bracelet, and which measures body temperature and the chemical composition of sweat in real time . The electronic bracelet is able to determine the amount of sodium and potassium ions, as well as glucose and lactic acid (lactate), and the received data is immediately transmitted to the smartphone.

By themselves, portable sweat analyzers are not new for a long time, but other similar devices can only monitor one substance, one molecule. If we have several sensors at once, this increases the reliability of information: for example, if the level of an ion has dropped sharply, then by other parameters you can tell exactly what the matter is: is it the ion itself, or is it that sweating has stopped, or our gadget just broke.

Obviously, the smart bracelet will be in particular demand among those involved in sports: by the concentration of ions, you can - even without getting off the simulator - understand whether you should take a break and drink water to prevent dehydration and muscle spasm, temperature tracking will prevent overheating , and lactic acid levels may indicate poor circulation. But, of course, such a device will also be useful for general medical purposes, especially if its authors manage, as they plan, to increase the number of molecules that their gadget can detect.

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