Indian space research organization conducted the first successful test of a hypersonic ramjet engines, according to Defense Aerospace. During flight tests of power plants the researchers tested the ignition at supersonic speed, steady burning fuel, the mechanism of air intake and fuel injection system.+

Hypersonic motor differs from the conventional in that the combustion in the chamber takes place in supersonic airflow. Air for combustion is fed into the chamber by the forward flow without the use of additional compressors: in-flight air flow enters the intake, then naujausius compressor chamber and thereafter into the combustion chamber.

Engines of this type are capable of operating at the speed of flight of at least four-five Mach numbers (4,9-6,2 thousand kilometers per hour). It is believed that the upper limit of the speed of a hypersonic engine is about 24 Mach numbers. For flight at high speeds the engine will require the injection of additional portions of oxidant.

Using hypersonic ramjet engines in launch vehicles would eliminate part of the liquid oxidizer, which would be necessary only natmosphere phase of flight. The advantage of the scramjet is that they are quite powerful and used for combustion air.

Indian hypersonic test engines that run on hydrogen and atmospheric air, was held at the site Sriharikota on the East of the country. He started a slightly modified two-stage solid-fuel booster ATV. The second stage was mounted in unit with two hypersonic engines. A start was made on the ground in the Bay of Bengal, 320 miles from Sriharikota.

The total duration of the flight the second stage was 300 seconds. After the rocket was launched and has a top speed of six Mach numbers, control system turned on the ignition of hypersonic engines. The unit with the engines rose to a height of 70 kilometers. The duration of the power plants amounted to five seconds.

The entire flight from launch with Shriharikota before falling into the Bay of Bengal took place in automatic mode. It should be noted that the objective of the first tests of hypersonic engines have been checking the stability of their work, not the ability of power plants to accelerate vehicles to hypersonic speeds.

Today, the development of hypersonic vehicles involves several countries, primarily Russia and the United States. Both of these countries over the past few years has experienced several hypersonic vehicles. Hypersonic engines in the future will be installed on combat missiles, launch vehicles, unmanned aerial vehicles and fighter jets.

Google stopped work on the project modular smartphone Ara. The company will not pursue further development or serial production of the device, reports Reuters, citing its sources.

The vast majority of modern commercially available smartphones are manufactured in accordance with the concept of "as is" ("as is"). Depending on the manufacturer and model of phone the user has or no modification of hardware and the appearance of the smartphone or have the ability to change the back cover and insert the memory card. This approach limits the possibilities of repair and does not allow the user to replace any components on the more powerful — if necessary, upgrade he is forced to buy a new device entirely. An alternative could be modular smartphones that allow users to rebuild the phone, depending on the needs.

The developer of Google's Felipe Hoffa on the results of the analysis of more than a billion files from 400 thousand repositories on GitHub found that the code formatting with spaces is in General used more frequently than the formatting tab. About the author said in the blog post on Medium.

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For readability of the program code, the vast majority of programmers use the indentation formatting — this allows you to highlight code in separate blocks. While some developers create indented a few spaces, while others use tabs. The main problem of this approach is that when working on a project a few people that use different indentation, formatting incorrect, and the code becomes difficult to read. 

Felipe Hoffa decided to determine what indentation is used more often, which used Analytics service BigQuery. Through the service the author has selected and processed 400 thousand repositories, the highest scoring user on GitHub for the period from January to may 2016, the amount of data processed was 14 terabytes.

The problem of different indentation has existed long enough and is often caused by fruitless disputes in a professional environment. In fact, the question of "blanks or tabs" represents an exemplary holivar, in which both sides have their arguments(1, 2), but no one is going to go to the other side. The phenomenon is also reflected in modern culture — for example, one of the scenes in the TV series "Silicon valley" is built around the problem of spaces or tab".

American and Mexican geophysicists called the cause of the strongest earthquake, which occurred in the XIX century in the area of the new Madrid seismic zone. Then, according to eyewitnesses, part of the Mississippi river for some time flowed backwards. Devoted to the study published in the journal Geophysical Research Letters, briefly about it reports the edition of Science News.+

The cause of the earthquake, the scientists saw in the rift — long, round depression in the bark, which originated 540-700 million years ago, formed when the North American plate. This has led to its deformation — under new Madrid seismic zone, as the researchers note, and is encountered in the ancient rift.

It contains a layer of dense lower crust, which over time is lowered. This process is accompanied by release of energy of deformation that leads to earthquakes. Colleagues earlier scientists had already put forward such a hypothesis, however, only in the latter study, it was possible to verify experimentally and to confirm by means of computer simulation.

The earthquake is interesting because it is located in the center of the North American plate. Similar devastating disaster occurs, as a rule, in the vicinity of tectonic faults, therefore their nature is more understandable to scientists.

Three earthquakes of magnitude more than 7.0 in the area of the new Madrid seismic zone occurred in 1811-1812. They are the largest known earthquakes East of the Rocky mountains in the United States. Geophysics plan to make a detailed seismic map of the territory to continue to use her to predict future disasters.

Automaker Mercedes-Benz and designer of the small transport Matternet quadrocopter introduced the concept of a logistics system using vans and Autonomous drones. For more information you can read on the website of the automobile concern Daimler AG and in the press release Matternet.

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In logistics there is the concept of "last mile", which is used to denote the last stage of delivery — directly to the client. "The last mile" in economic terms, costing and supply the most expensive, since, at intermediate points, the cargo goes in bulk. According to the British company Starship Technologies, the use of wheeled drones can reduce the cost of"last mile" 10-15 times, and delivery drones, theoretically, should be more profitable.

Materials published Daimler AG do not contain technical information and largely describe a design concept. However, according to Matternet, presented the Mercedes-Benz concept a working prototype. In particular, Matternet has developed mounted under the roof of the van system exact fit and replacement of load and battery, allowing you to use an Autonomous quadcopter to deliver small packages directly from the roof of the car.

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Matternet also presented the second version of its truck Matternet quadrocopter M2 — it can carry a weight of two kilograms to a distance of 20 kilometers. The first model Matternet ONE could take aboard only one kilogram, and the drone was even used in Switzerland as a mail drone.

Nikolai Vorontsov