In this article I would like to tell a story about the English steam engine, and how it became a small electric generator in a regular apartment.
Right from the beginning of the steam expansion in the XIX century, the different types of engines were built, including small and decorative engines. When the steam engine was a novelty, those models had been shown to the amazed audience, and when it became widespread, the steam engines turned into an excellent tutorial and a wonderful toy for the younger generation of creators of the Industrial Revolution. So, at the end of Victorian era and at the beginning of Edwardian era the companies began making toy steam engines. In the XX century, namely in 1937, when the steam machineries lost their popularity, in the United Kingdom appeared Mamod firm, the name means Malins Models. Since then this firm has been providing the steam engines for everybody. So in the 60s, they have supplied with the engine an unknown person who sold this engine to another person that put up for sale this unit on eBay. The engine is worn out. After winning the auction I paid for this unit and got it by the Russian Post. In my hands I was holding a box with Royal Mail stamps and the inscription “Steam engine”.
Generally, in order to manufacture a typical solar panel the silicon workpieces are cut into wafers, and their thickness is about 200 microns. However, only a thin surface layer of the wafer is used directly. In addition, a portion of the silicon goes to the waste in the process of cutting. Company Twin Creeks Technologies has developed a manufacturing system, Hyperion, which is based on an entirely different principle. Hydrogen ions are embedded into the silicon wafers at a certain depth, and then inside of the workpiece is formed a thin layer of hydrogen bubbles. Next, the workpiece is heated and a gas pressure makes a thin layer of silicon to exfoliate, whereupon the cycle is repeated again. The resulting silicon lamina has a thickness of 20 microns, which is applied to a metal base. This ultra thin wafer is easy to bend without breaking.
These solar panels that are made by Twin Creeks Technologies cost half the price of conventional panels, less than 50 cents per watt. The company's website states that this technology will allow the solar electric installations to compete with the conventional energy sources.
The purpose of this article is to satisfy the curiosity of people who are interested in the inner life of the Internet giant Amazon, as well as to warn the owners of online shops from all sorts of pitfalls.
IP-address (v4) is consisted of 32 bits. Any self-respecting administrator or IT specialist should answer correctly the question: "How many bits are in an IP-address?" Of course, It is desirable to know about IPv6: 128 bits.
Here is a first case. Theoretically IPv4-addresses can be:
232 =210*210*210*22 = 1024*1024*1024*4 ≈ 1000*1000*1000*4 = 4 billion
Below we could see that a lot of them are "eaten up" by any garbage.
I think everyone knows how IPv4-address is written. The four octets (it is the same as byte) in decimal with no leading zeros, separated by dots: “192.168.11.10”.
In recent years there has been a tendency to make out the graphics in the form of fonts. It really simplifies a lot. But there are difficulties of a practical nature: Where do I get the font with the symbols that are needed for me? Most often it turns out that you need a couple of icons from one font, a couple icons from another, etc. Moreover, each font designer has his own vision in terms of mapping glyphs. It is very inconvenient to plug in all that.
I got an idea to build a tool that could make font by a simple click of a mouse. Profit is obvious you get the font of the minimum size just to suit your specific needs. You get fontomas :).
Recently, a new excellent Time.is service has started its operation. This service is showing the approximate mistiming of your computer clock with the international atomic time (usually an error in Ajax is 0.02-0.1 s.). Also, it shows the time in 7 million places in the world and compares the time in different places.
Previous articles about the icons have generated a lot of interesting questions about the drawing technique, namely mini-illustrations. I will try to uncover this simple mystery :)
I am not going to give you a detailed description of that, because this would require writing a series of lessons, but I want to share a common principle.
I took the icon from the current project as an example.
Rizzoma is a collaborative tool, an alternative to Google-wave.
During working on the website was born the idea of making beautiful icons for each block with the benefits. The snail symbolizes the context messages and essentially it is an advanced symbol @.
Usually working on an icon starts with a pencil drawing, but this time here are enough inspiring Fast snail images. It was decided to make own version of the beautiful and charming snail with a turbine.
According to the experts’ opinions, a rough estimate of Facebook value after the stock market launch (IPO) will make $ 100 billion U.S. dollars. Now Zuckerberg's brainchild will be next to such giants as Disney ($ 70 billion), Billiton ($ 72 billion), Amazon ($ 82 billion) and McDonald's ($ 101 billion). People enthusiastically clap their hands and count the approximate income from shares in the first year of trading.
Recently, I have read some article where was a discussion about multiple use of cryptographically strong hash for a password. That discussion has pushed me to a math topic. The essence of the problem arises from the idea of multiple (1,000 or more times) password processing before storing by any cryptographically strong algorithm (typically, it is a hash function) in order to get a slow algorithm of verification that effectively resists brute force in case of interception or theft of this value by an intruder . This idea is not new, and it is used by the developers of Cisco, RAR and many others. But, as far as hashing is an operation that compresses many values, there is a logical question - don’t we damage the resistance of system? I will try to answer this question.