Why in some countries there is no 13th floor in houses? Detailed answer

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Why in some countries there is no 13th floor in houses? Detailed answer

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Why do houses in some countries not have a 13th floor?

Because of the fear of the number 13, in many countries there is no 13th floor in houses (after the 12th floor, the 14th floor immediately follows), or it is indicated differently, for example, 12A or M (13th letter of the alphabet).

Authors: Jimmy Wales, Larry Sanger

Random interesting fact from the Great Encyclopedia:

Where did the first mirror appear?

Have you ever looked into the water of a lake? Did you see the reflection of the trees and the sky there? Essentially you were looking in a mirror. After all, a mirror is a smooth surface that reflects light and other objects.

It is very important that its surface is smooth. The smoother it is, the better the reflection. When the breeze ruffles the water, you can only see the sun's reflections - and no other objects.

In ancient times, mirrors were made of polished metal. Now the mirror is made of smooth glass with a layer of metal on the back. The glass itself is not yet a mirror: the reflection gives us a narrow layer of silver, and the glass only protects it from scratches and damage.

We will never know when a man came up with a mirror. Probably, he also often looked into the smooth surface of the pond and saw himself there. Perhaps, by chance, he learned that the polished metal can also reflect objects. One fine day (we know almost certainly that a woman suggested this idea) a person began to specially polish pieces of metal and give them the desired shape. So there were mirrors.

And in the times of ancient Greece, Egypt and Rome, people already widely used mirrors. Even then they had small pocket mirrors that were comfortable to carry around. They were made from a circular plate of metal: copper, bronze, silver and gold.

Just as a child is surprised when he sees his own reflection, ancient people were surprised in the same way. They did not know how a reflection is obtained, so they attributed magical powers to mirrors. They thought that what they see in the mirrors is their spirit. Thus arose the superstition that if you break a mirror, it can harm the Spirit.

The first who guessed to make glass mirrors with a layer of mercury or tin were the Venetians. By 1300 they were producing such mirrors, and they soon replaced the metal plates. We use them to this day.

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Samsung Exynos 5 1080nm SoC 16.11.2020

Samsung has introduced Exynos 1080, a single-chip system for the next generation of mobile devices. And this is Samsung's first 5nm SoC (until now, only TSMC was able to do 5nm).

Samsung has announced the Exynos 1080, its first 5nm SoC for the next generation of smartphones

The Exynos 1080 platform is an update of last year's Exynos 980 model. But if the old one was produced using the 8 nm process technology (8 nm Low Power Plus FinFET), then the new one is produced using a more advanced 5 nm technology with lithography in the hard ultraviolet range (EUV). Another benefit of the Exynos 1080 over competing SoCs is the built-in 5G modem. That is, on the PCB and therefore in the device case, this SoC will take up less space than any other platform when combined with a separate 5G modem. The module provides data transfer rates of 5,1 Gbps in 5G NR Sub-6 GHz networks and up to 3,67 Gbps in 5G NR mmWave networks. The Samsung Exynos 1080 also supports the new Wi-Fi 6 (802.11ax) standard and Bluetooth 5.2.

The Exynos 1080 configuration includes a three-cluster eight-core CPU (one older Cortex-A78 core with a frequency of 2,8 GHz, three medium Cortex-A78 cores with a frequency of 2,6 GHz and four junior Cortex-A55 cores with a frequency of 2,0). Graphics processing is entrusted to the built-in Mali-G78 MP10 GPU.

Exynos 1080 also includes an integrated neural processing unit (NPU), which is responsible for accelerating the processing of artificial intelligence tasks. Its performance is 5,7 trillion operations per second.

The SoC also includes a high-performance image processor that supports cameras up to 200 MP, multi-module configurations of six cameras, as well as video with 10-bit color and HDR10+.

From the rest, we can note the multi-format codec (MFC), hardware encoding and decoding of 4K UHD video at 60 fps, and 90 Hz at WQHD + resolution or 144 Hz at FHD +.

Smartphones with SoC Exynos 1080 will enter the market next year, and the vivo model (flagship X60) will be the first to receive this platform.

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