Tip 1: How to protect beaches from sharks

Travel and tourism

Tip 1: How to protect beaches from sharks

In 2011 in Russia near Primorye appearedsharks. A number of attacks on humans were recorded at the end of the summer. After that, all the forces were thrown to catch and neutralize the predator. As a result, they found her. Now the authorities of the region are concerned about how to prevent those events again and again, and developed a whole plan of measures to protect against sharks.

No one expected that this could happen inPrimorye. Vacationers boldly swam, when suddenly a predator attacked one of them. The young man was seriously disabled. As one of the security measures adopted this year, was the installation of special networks that will not miss sharks closer to the shore. The construction is a structure in the form of the letter "P", which can block off 100-200 meters of the sea territory. Accordingly, in order to block the whole bay, it will be necessary to have several such hydraulic structures at once. Their width is 50 meters. Installation of such a design is not an expensive pleasure and will cost 100 000-150 000 rubles. True, the shelf life is quite long - it will last for several years. At the moment, regular patrols are conducted on the water to identify sharks in dangerous proximity to the coastline. Also, at the suggestion of the authorities, it was decided to organize special observation posts on land to monitor the state of the sea. They will be on the dais in close proximity to the beach. As a preventive measure on the beaches are placed plaques that warn of a possible attack by marine predators. But abroad, in addition to these networks, additional measures are also used to protect vacationers on seashores. So, for example, the Italians have developed special devices, which are shields. The essence of their work is that it has electromagnetic radiation. After catching such waves, sharks will feel danger and will not dare to approach closer to the shore. Plus, such screens are also in the fact that this design is an order of magnitude smaller than the networks, does not take up so much space and does not restrict entry to the bay. In Israel, however, special systems for monitoring marine animals are used. They work in a complex - from the air and from the water. Air surveillance is carried out by special services, which from helicopters study the situation at sea. On the water side, special powerful radars are used that capture the vibrations produced by sharks and transmit information to the sensors. Then the shark is either driven off or destroyed.

Tip 2: How to protect yourself from sharks

In some picturesque places of our planet, rest on the sea coast can turn into a tragedy because of the attack Sharks. Such cases are rare, but they also have a place to be. The most common victims of these predators are divers and surfers, as well as people who swim too far from the shore. How realistic is the attack SharksS yourself?

Instructions

In many countries special documents are issued for military seamen, such as a memo on Sharksah, but the special rules of confrontation SharksAm not. There are universal tips, but how effective they are is not known. If you noticed a fin nearby, dissecting waves, then, most likely, Sharksand has already chosen a potential victim and is currently hunting. Perhaps, this sacrifice is you.

According to one of the hypotheses there is a chance to escape,pretending to be dead. This option can "work" if around in the water there will be a few floundering living beings or bodies. It is difficult to imagine this way of salvation, because SharksBut, not yet making an attack, swimsso close to the victim that her too coarse skin mercilessly rips apart pieces of human skin with meat at the slightest touch. And the smell of blood, these predators react lightning fast.

Shark teeth are as sharp as a razor. A couple of bites can tear a person to pieces. Upper jaw Sharkss not connected with the skull, so it is convenient to dismember the victim, shaking his head and swallowing at the same time. Despite this, SharksThey are naturally shy. There is a version that they can be chased away altogether or at least for a while, inflicting heavy blows on the nose, gills, eyes. Sharks are so unpredictable that they can abruptly stop harassment if the victim repels. But it is impossible to say exactly how a predator will behave.

Disputes also contend that scare away SharksYou can, slapping your hands on the water or a loud cry. After all, slapping reminds predators, for example, fur seals, which are for them coveted prey. Vision at Sharks They are able to see only the silhouette. And with a cry, the victim risks attracting a predator. There is a variant from the series "The best attack - attack", that is, try to swim swiftly towards SharksE. In many cases, predators are afraid and float away. But by going to this step, the victim herself signs an instant death sentence.

Tip 3: We are watched from heaven

Governments of different countries are concernedIncrease in the use of radio-controlled unmanned aerial vehicles throughout the world. Now everyone can buy a small UAV with a camera and look there - wherever he should.

In some courts, there are already claims for invasion of privacy through radio-controlled drone. And in France there was an outrageous case of aerial survey of nuclear power plants.

And only the governments of several countries were concerned with the regulation of this issue: the Spanish government imposed a ban on UAV flights, and the Australian government limited the flights to licensing.

Also, uncontrolled use of drones can lead to air crashes. So, several cases of UAV appearance in the flight zone of passenger aircraft have already been registered.

However, the use of drones gives a number ofOpportunities. For example, in Australia, UAVs control ocean beaches and transmit alarm signals in the event of the appearance of sharks in the water area. In a number of countries, they are used for various accidents and man-made disasters. They are also actively used by the warring parties in the Donbas, both for conducting combat operations and for peaceful journalistic reporting.

Soon this issue will arise sharply in theRussia. Already, the shelves of stores are filled with models of aircraft and helicopters. But there are also more serious examples, for which it is already possible to install video cameras with a decent stock of flight time and range.

Tip 4: What types of sharks are considered to be the largest

Sharks are not only one of the most ancientspecies of fish, but can still be among the largest representatives of the underwater world. It is no coincidence that predatory sharks become the characters of many horror films. The size of some individuals is amazing. These fish can rightfully be considered kings of the seas and oceans.

What kinds of sharks are considered to be the largest

Not so long ago, the largest of the sharks zoologistsConsidered a large white shark - carcharodone (Carcharodon carcharias). It and to this day is such among the known predatory sharks. The length of the average specimen is 5-6 m, and the usual weight is 600-3200 kg. The largest of the representatives of this species reached 11 m. There is a suggestion that larger individuals may also occur.

An even larger species of sharks and moreThe largest fish known to date in the world is the whale shark (Rhincodon). Its usual sizes reach 10-14 meters. There are also giant specimens at 18 m.

In 1990, there appeared scientific information onA specimen of a whale shark 20 meters in size and weighing 34 tons, which is approximately the weight of the average sperm whale! This fact in modern sources is indicated as verified.

The whale shark is a very small species. Unlike a kinswoman, a large white shark, she is not dangerous and eats plankton, decanting it from the water. It is not aggressive and behaves peacefully. Some researchers of the underwater world even managed to touch it.

The whale shark floats rather slowly, cruisingNear the water surface with an average speed of 5 km / h. For a long time this species of sharks was unknown. For the first time scientists managed to get to know him in 1828, when sailors extracted 4.5-meter fish.

Tip 5: How to Forge Samurai Swords

Japanese swords are considered the pinnacle of developmentmedieval metallurgy and real works of art. The technology of their manufacture was kept for a long time by blacksmiths in secret, and some subtleties are not known until now.

Steel smelting

Japan is poor in iron ore, soto obtain high-quality iron billet for several years buried in the ground or submerged in the swamp. During this time, harmful impurities and slags were removed from the iron. After the blanks "rested", the smith proceeded to forge. The iron ingots were converted into plates which were folded twice several times, reaching not only the multilayer structure of the steel, but also an equal content of carbon throughout it, which protected the blade from destruction due to its heterogeneous composition.

Modern researchers believe that Japanese swords were only slightly higher than European counterparts, since the main technological stages coincided.

To make a real Japanese swordAt least two types of steel were used: solid - with high content of carbon and viscous - low-carbon. The smiths combined steel of different hardness to combine the strength needed for the cutting edge in the blade and the flexibility that protected the sword from damage when striking. In the most complex swords, up to seven types of steel were used, but the resulting blades possessed the best characteristics. After forming the blade blanks, the heat treatment step, that is, hardening, occurred. It is the hardening that provides the cutting edge of the sword with the necessary strength and resistance to mechanical stress. In this case, the blacksmiths solved the problem of simultaneously maintaining the flexibility of the blade. This was achieved through the technology of so-called uneven hardening. The blade was applied a special composition based on clay and ash with the addition of secret ingredients, and the thickness of the layer was different: thinner than all on the cutting part, the thickest - in the middle of the blade.

From the workpiece to the blade

The sword thus prepared was heated tothe temperature is approximately 760 ° C, after which it was sharply cooled. As a result, the metal changed its structure, achieving the highest strength in the area where the layer of the composition was the most thin. In addition, on the border of the cutting part and the main surface, a special pattern was formed, according to which the masters assessed the quality of the blacksmith's work. By the way, the curved shape of the blades in some cases was achieved by deformation during the quenching process.

Around the Japanese swords are piled up a huge number of different myths. The miraculous properties of the samurai weapons are often propagated in Western films.

The final stages of the creation of the Japanese sword -grinding and assembly. To make the blade shine, the master polisher used up to sixteen types of grinding stones of varying degrees of granularity. After polishing, a patterned round garda and a handle fitted with a shark or skate skin attached to the blade, letting the sword do not slide in the palm of your hand. Sheath for the sword was made of lacquered wood, in particular, magnolia.

Tip 6: How do you scare away sharks

The shark is a predatory cartilaginous fish, which has become diligentcinematographers with the embodied horror of the seas and oceans. In fact, according to statistics, in 2009, 2,371 people were attacked by sharks around the world, 464 of whom were killed. For comparison, in the same year only 43,000 people died in an accident in the United States.

Nevertheless, almost half a thousand people areNot at all small. Scientists have long been looking for ways to scare away sharks. In 1937, the beaches of Sydney at night began to wall out the shuttle nets. After that, no shark attacks per person were recorded in the fenced areas. Moreover, the number of these predators caught in the night on the network declined year after year-either sharks in the seas became less, or they learned to recognize the danger. In 1952, networks as protection from sharks began to be used in Durban (South Africa) with The same success - no attack on bathers. However, this method has a significant drawback - harmless animals die on the networks, over which the threat of extinction is already hanging: dolphins, sea turtles, etc. Akula possesses very sensitive sensors that pick up weak currents and sound vibrations, as well as smells. This feature of predators is used in the creation of various repellents (repellents). A weak electromagnetic field, safe for other marine creatures and humans, can stop the shark and make it stay away from the radiator. American scientists developed a device Shark Shield ("Shield from sharks"). It can be attached to a boat, a surfboard or to a compressed air cylinder. Generated electromagnetic radiation, according to the developers, can keep a shark at a distance of several meters. The sound emitter is similarly arranged. The shark perceives low sound and infrasound. High frequencies cause her discomfort. It is assumed that the ultrasound generator will frighten off the predator. However, tests of all types of radiators have shown that there is no universal repellent: one that scares a shark of one kind is ignored by another. Developed and chemical means of protection from these formidable fish. It is noticed that sharks try to stay away from the decaying corpses of their relatives. Scientists have synthesized a substance that mimics the cadaveric shark smell. Experimental tests have shown a certain effectiveness of this tool.

Tip 7: How sharks attack people

Despite the fact that a person is not aThe favorite food of sharks, these dangerous and at the same time amazingly beautiful creatures continue to attack people. Scientists are trying to find out the exact causes of such aggressive behavior, but until now many moments remain a mystery. And the process of attack is often different, depending on the type of shark and situation.

Instructions

There is a statistics according to which victimsThe attacks of sharks annually range from 80 to 100 people. And only a few of them get wounds that lead to death. Such figures do not make of sharks monsters, which they are often exposed in films. Moreover, the person himself often goes into contact with them, not observing the elementary rules of safety, for example, during entertainment excursions offering swimming with sharks in the ocean.

It is believed that out of the existing 370 speciessharks only representatives of four can attack a person. This white shark, tiger, long-winged and tupory. And some species generally eat exclusively plankton and jellyfish.

The main reason for the shark to attackthe presence of blood in the water. Because of this, this predator simply loses control of itself and can attack without parsing. And the blood can be not only human, but also any fish.

In addition, the shark can simply be confuseda man with a marine life, since her vision is rather weak. Usually this occurs in troubled waters. It is for this reason that sharks are often the victims of sharks - the board and the limbs hanging from it remind the predators of seals and sea lions.

Sharks become more aggressiveIf they feel threat from a person. That is why attempts to deter an approaching shark often lead to the opposite effect. In addition, sharks, like many predators, feel the fear coming from the living being, which also attracts their attention and provokes them to attack.

Quite often a shark bite can beIt was provoked by simple curiosity. Since she does not have sensitive limbs, the only way to find out about the marine life for her is to try to bite. That's why scientists advise not to swim in the habitats of these predators at night, in the evening or early in the morning - at this time they hunt.

Usually sharks long circle around the chosen oneVictim, watching her and studying her behavior. Then they make one swift attack. After that they can either leave their victim alone for some reason, or else move away from it for a while. In the latter case, they simply try to protect themselves from a possible dangerous reaction for them and wait for the victim to weaken.