15 April 1988 , began flight tests of the Tu–155, the first plane that used hydrogen as fuel. The plane was built in a single copy specifically for test flights on cryogenic fuel. It was built on the basis of the Tu–154, in which the two engines use the usual aviation kerosene, and the third liquid hydrogen or liquefied natural gas. In total, done about 100 flights, and only five of them are hydrogen. The rest of liquefied natural gas.
Experimental aircraft Tu-155
Experimental aircraft Tu-155
For the testing time of the Tu–155 has set 14 world records. While mass production of hydrogen engines is not reached until now. However, the experimental framework and all the knowledge accumulated during the test will quickly establish the production of airplanes using cryogenic fuel. Of course, if need be.
April 15, 2014, exactly one year ago, Google launched a sale of its smart glasses. Until glasses were sold only to journalists and enthusiasts, which Google independently selected from total number of applicants.
During the day, Google Glass could be ordered by anyone over the age of 18 years living in the U.S. (or, more precisely, having a mailing address in the country) and having 1500 dollars. Interestingly, Google has not announced how many points were able to implement during the campaign, and opinions of experts were divided: some said about the hundreds of devices that operated on thousands of others. But anyway a truly massive smart glasses, and steel. And in January this year, Google completely shut down the work on the project – possibly forever.
15 April 2004 , began connecting subscribers to a mobile network in North Korea. Up to this point, the communication services could benefit only the highest-ranking party leaders and heads of large enterprises. At the time of starting the connection service to the network was worth about 900 dollars and the average salary in the country, was barely over $ 10 a month.
Pyongyang residents with mobile phones
However, this point can be called a turning – mobile communications in the country slowly began to develop. By the end of 2010, the country had around 400 thousand subscribers, and by the end of 2011 – more than 800 thousand. By the beginning of 2013 the number of subscribers exceeded 2 million, and foreign tourists stopped to take cell phones at the airport and allowed them to use mobile Internet.
April 15, 1999 was born the blog platform Livejournal. The most popular in Runet service for conducting online diaries has developed a 19-year-old programmer from the USA brad Fitzpatrick – he created a small site for yourself and your classmates, where you can communicate and share brief notes.
Livejournal in 1999
Social networks in the global Internet did not yet exist, and to discuss events outside of Internet media, many wanted, so the brainchild of a young programmer became popular, and after the opening of free registration, the online resource was developed on the principle of “word of mouth”.
In 2002, the project began to transform from Amateur to commercial. Fitzpatrick registered management company Danga Interactive and added a bit more functionality the paid account.
However, with the return of the resource situation was not very good, so already in 2005 Livejournal with 15 million users was purchased by SixApart, and after a couple of years to wildly popular in Russia the resource has expressed interest in the company SUP Media (now part of the holding “Rambler-Afisha-SOUP”). First SUP took over the development of the Cyrillic blogs, and then bought Livejournal from the American owners of the whole.
Livejournal in 2016
The popularity of online blogs significantly declined with the spread of social networks, but in Runet Livejournal was always more than just diaries, and scandalous public “tribune,” and for this reason, the service still is in the TOP 20 most visited Russian sites.