Which Computer Keyboard Keys Wear Out the Fastest?

If you spend a lot of time using a computer, you've undoubtedly noticed that over time, some of the letters on your keyboard start to disappear. That leads to the question: Which keys on a keyboard tend to wear out the fastest?

Since keys wear out because of use, it's logical to assume that the keys that wear out the fastest are the ones we use most heavily. Back in the days before computers, when typewriters and typesetting machines were used to put words on paper, that was a fairly easy question to answer. As a trade publication called The Inland Printer noted back in 1898, it was widely accepted that the most-used key on keyboards was the space bar, followed by the letter E.

But habits changed these days. That's because a lot of people who were once casual computer users have switched to using smartphones and tablets with touchscreens to write emails and check out social media and videos, and the people who still use laptops are mostly either workers or computer gamers.

Gamers mostly order replacements for the W, A, S and D keys, as well as the arrow keys. People who use desktop and laptop computers for work, in contrast, tend to replace the vowel keys — A, E, I, O and U — and the spacebar and the arrow keys, which are the keys pressed most often when typing.

A gamer's keyboard - W, A, S, D are worn out more than the others

A regular user's worn out keyboard - observe the key 'W' is intact unlike in the case of the gamer's keyboard

There are three ways to count letter frequency in English. The first method is to count letter frequency in root words of a dictionary. The second is to include all word variants when counting, such as "abstracts", "abstracted" and "abstracting" and not just the root word of "abstract". This system results in letters like "s" appearing much more frequently, such as when counting letters from lists of the most used English words on the Internet.

The third method is to count letters based on their frequency of use in actual texts, resulting in certain letter combinations like "th" becoming more common due to the frequent use of common words like "the". Absolute usage frequency measures like this are used when creating keyboard layouts or letter frequencies in old fashioned printing presses.

Relative frequencies of letters in text

English letter frequencies in text, sorted by frequency

In English, the space is slightly more frequent than the top letter (e) and the non-alphabetic characters (digits, punctuation, etc.) collectively occupy the fourth position (having already included the space) between t and a.

Sources -

1. Wikipedia
2. HowStuffWorks.com

Rudolf Diesel, Diesel Engine & SS Dresden

March 18, 1858 - birthday of Rudolf Christian Karl Diesel, a German inventor and mechanical engineer, famous for the invention of the diesel engine, and for his mysterious death.

Diesel was born to Bavarian parents who were immigrants living in Paris. His father was a bookbinder by trade. At the outbreak of the Franco-Prussian War in 1870, his family left Paris and settled in London. Diesel's mother sent 12-year-old Rudolf to Augsburg to live with his aunt and uncle to become fluent in German and to visit the Königliche Kreis-Gewerbeschule (Royal Circle Vocational College), where his uncle taught mathematics.

At the age of 14, Diesel wrote a letter to his parents saying that he wanted to become an engineer. After finishing his basic education at the top of his class in 1873, he enrolled at the newly founded Industrial School of Augsburg. Two years later, he received a merit scholarship from the Royal Bavarian Polytechnic of Munich, which he accepted against the wishes of his parents, who would rather have seen him start to work.

Royal Bavarian Polytechnic of Munich which was later rechristened as Technical University of Munich (TUM). TUM is ranked 4th overall in Reuters 2017 European Most Innovative University ranking. TUM's alumni include 17 Nobel laureates, 18 Leibniz Prize winners and 22 IEEE Fellow Members

Department of Mechanical Engineering, Technical University of Munich

One of Diesel's professors in Munich was Carl von Linde. Diesel graduated in January 1880 with highest academic honours and returned to Paris, where he assisted his former Munich professor, Carl von Linde, with the design and construction of a modern refrigeration and ice plant. Diesel became the director of the plant one year later. While Diesel continued to work for Linde, gaining numerous patents in both Germany and France. He later moved to Berlin to assume management of Linde's corporate research and development department.

Carl Paul Gottfried Linde was a German scientist, engineer, and businessman. He discovered a refrigeration cycle and invented the first industrial-scale air separation and gas liquefaction processes. These breakthroughs laid the backbone for the 1913 Nobel Prize in Physics won by Kamerlingh Onnes.

As he was not allowed to use the patents he developed while an employee of Linde's for his own purposes, he expanded beyond the field of refrigeration. He first worked with steam and his research (research into thermal efficiency and fuel efficiency) led him to build a steam engine using ammonia vapour. During tests, however, the engine exploded and almost killed him. He spent many months in a hospital, followed by health and eyesight problems.

He then began designing an engine based on the Carnot cycle and published a treatise entitled Theorie und Konstruktion eines rationellen Wärmemotors zum Ersatz der Dampfmaschine und der heute bekannten Verbrennungsmotoren (Theory and Construction of a Rational Heat Engine to Replace the Steam Engine and The Combustion Engines Known Today) which formed the basis for his work on and invention of the diesel engine. This was just after Karl Benz was granted a patent for his invention of the motor car in 1886.

US Patent documents of the Diesel Engine

Diesel observed that as much as 90% of the energy available in the fuel is wasted in a steam engine and his work in engine design was driven by the goal of much higher efficiency ratios. Eventually, he obtained a patent for his design for a compression-ignition engine. In his engine, fuel was injected at the end of compression and the fuel was ignited by the high temperature resulting from compression.

On the evening of 29 September 1913, Diesel boarded the GER steamer Dresden in Antwerp on his way to a meeting of the Consolidated Diesel Manufacturing company in London. He took dinner on board the ship and then retired to his cabin at about 10 pm, leaving word to be called the next morning at 6:15 am; but he was never seen alive again. His death continues to be a mystery till this day.

SS Dresden - a British passenger ship which operated from 1897 to 1915; she is known as the place of the 1913 disappearance of German engineer Rudolf Diesel

The diesel engine underwent much development after Diesel's death and became a very important replacement for the steam piston engine in many applications. The diesel engine was widely used as stationary engines, agricultural machines, submarines, ships, and much later, locomotives, trucks, and in modern automobiles.

The diesel engine has the benefit of running more fuel-efficiently than gasoline engines due to much higher compression ratios and longer duration of combustion, which means the temperature rises more slowly, allowing more heat to be converted to mechanical work.

Diesel was interested in using coal dust or vegetable oil as fuel, and in fact, his engine was run on peanut oil.

Rudolf Diesel on a German postage stamp

Sources -

1. Diesel: The Man and the Engine by Morton Grosser
2. Wikipedia

Kalpana Chawla & Space Shuttle Columbia

March 17, 1962 – birthday of Kalpana Chawla, an Indian American astronaut and the first woman of Indian origin in space. Kalpana Chawla was born in Karnal, Punjab (now in Haryana). Her official date of birth was altered to 1 July 1961 to allow her to join school underage.

After getting a Bachelor of Science degree in Aeronautical Engineering from Punjab Engineering College, Chandigarh, she moved to USA in 1982 where she obtained the Master of Science degree in Aerospace Engineering from the University of Texas in 1984.

Punjab Engineering College

Chawla went on to earn a second Masters in 1986 and a PhD in aerospace engineering in 1988 from the University of Colorado, Boulder. She held a Certificated Flight Instructor rating for airplanes, gliders and Commercial Pilot licenses for single and multi-engine airplanes, seaplanes and gliders.

Logo of University of Colorado Boulder.

After becoming a naturalized US citizen in April 1991, Chawla applied for the NASA Astronaut Corps. She joined the Corps in March 1995 and was selected for her first flight in 1996. Her first space mission began on November 19, 1997, as part of the crew that flew the Space Shuttle Columbia flight STS-87.

Columbia launches on STS-87

The STS-87 patch is shaped like a space helmet symbolizing the Extravehicular Activity (EVA) on the mission in support of testing of tools for the assembly of the International Space Station (ISS). Earth is shown reflected on the backside of the helmet. The Space Shuttle Columbia forms the interface between the Earth and the heavens, the back and front sides of the helmet in profile. The three red lines emerging from Columbia represent the astronaut symbol as well as the robot arm, which was used to deploy and retrieve the Spartan satellite.

The text 'µg' represents the payloads studying microgravity science in space on this United States Microgravity Payload (USMP-4) mission. Gold flames outlining the helmet visor represent the corona of the Sun, which will be studied by Spartan. The flag of Ukraine is next to the name of the payload specialist who is the first person from that nation to fly on the Space Shuttle.

Chawla was the first Indian-born woman and the second Indian person to fly in space, following cosmonaut Rakesh Sharma who flew in 1984 on the Soyuz T-11.

 

In 2000, Chawla was selected for her second flight as part of the crew of STS-107. This mission was repeatedly delayed due to scheduling conflicts and technical problems such as the discovery of cracks in the shuttle engine flow liners. On January 16, 2003, Chawla finally returned to space aboard Space Shuttle Columbia on the ill-fated STS-107 mission. Chawla's responsibilities included the microgravity experiments, for which the crew conducted nearly 80 experiments studying earth and space science, advanced technology development, and astronaut health and safety.

Space Shuttle Columbia lifts off from Launch Pad 39A on mission STS-107. Launch occurred on 16th January, 2003

Insignia for STS-107 - a multi-discipline microgravity and Earth science research mission with a multitude of international scientific investigations conducted continuously during the planned 16 days on orbit. The central element of the patch is the microgravity symbol, µg, flowing into the rays of the astronaut symbol.
The mission inclination is portrayed by the 39 degree angle of the astronaut symbol to the Earth's horizon. The sunrise is representative of the numerous experiments that are the dawn of a new era for continued microgravity research on the International Space Station and beyond. The breadth of science conducted on this mission will have widespread benefits to life on Earth and our continued exploration of space illustrated by the Earth and stars.
The constellation Columbia (the dove) was chosen to symbolize peace on Earth and the Space Shuttle Columbia. The seven stars also represent the mission crew members and honor the original astronauts who paved the way to make research in space possible. The Israeli flag is adjacent to the name of the payload specialist who is the first person from that country to fly on the Space Shuttle.

The crew of the Space Shuttle Columbia, mission STS-107. From left to right are mission specialist David Brown, commander Rick Husband, mission specialist Laurel Clark, mission specialist Kalpana Chawla, mission specialist Michael Anderson, pilot William McCool, and Israeli payload specialist Ilan Ramon.

During the launch of STS-107, Columbia's 28th mission, a piece of foam insulation broke off from the Space Shuttle external tank and struck the left wing of the orbiter. It was suspected that the damage to Columbia was more serious than in the previous shuttle launches but the investigation was limited with the reasoning that the crew could not have fixed the problem if it had been confirmed. When Columbia re-entered the atmosphere of Earth, the damage allowed hot atmospheric gases to penetrate and destroy the internal wing structure, which caused the spacecraft to become unstable and slowly break apart.

One of the Space Shuttle Columbia's Main Engine powerheads found on the ground

The Final Report of the Columbia Accident Investigation - download the info-graphic here

You can download the above files using the following the hyperlinks -

1. Kalpana Chawla
2. Columbia Accident Investigation Report

Primary Source - Wikipedia

Where are tomorrow’s female scientists?

The Programme for International Student Assessment (PISA) is a triennial international survey which aims to evaluate education systems worldwide by testing the skills and knowledge of 15-year-old students.

In 2015 over half a million students, representing 28 million 15-year-olds in 72 countries and economies, took the internationally agreed two-hour test. Students were assessed in science, mathematics, reading, collaborative problem solving and financial literacy. The results of the 2015 assessment were published on 6th December 2016.

In reading, 15-year-old girls outperform 15-year-old boys (by the equivalent of roughly one year of school), while in mathematics  boys outperform girls (though by a narrower margin, the equivalent of less than half a year of school); in science there is instead little difference between boys’ and girls’ performance.

Yet dig a little deeper and a more nuanced picture emerges. There are far more boys (24.9%) than girls (12.5%) among the lowest-achieving students in reading, while there are far fewer girls than boys among the top performers in mathematics (10.6% vs. 14.8%) and science (7.7% vs. 9.3%).

There are even larger gender differences in the fields of study chosen in higher education - in OECD countries, fewer than 1 in 3 engineering graduates and fewer than 1 in 5 computer science graduates are girls. This is likely because of stereotypes and expectations, rather than performance differences in math and science. For example, at age 15 far fewer girls (4.7%) than boys (18%) — even among the top performers — reported that they expect to have a career in engineering or computing.

Even when girls do graduate from scientific fields of study, they are much less likely than boys to work as professional in these fields, more often choosing to become teachers. Data from a subset of OECD countries show that, among graduates with science degrees, 71% of men but only 43% of women work as professionals in physics, mathematics and engineering. As a result, across OECD countries, only 13.7% of the inventors who filed patents are women.

Source - OECD

Send your name to the sun

NASA’s Parker Solar Probe mission – scheduled to launch in summer 2018 – will travel through the sun’s atmosphere and get closer to the solar surface than any spacecraft before it. You can send your name along for the ride.

To commemorate humanity’s first visit to our own star, NASA is inviting people around the world to submit their names online to be placed on a microchip aboard the Parker Solar Probe. Submissions will be accepted until April 27, 2018. Learn more and add your name to the mission here. Link to register your name

Illustration of the Parker Solar Probe spacecraft approaching the sun

The spacecraft, about the size of a small car, will travel directly into the sun’s atmosphere about 4 million miles (6.4 million km) from its surface. The primary science goals for the mission, said NASA, are to trace how energy and heat move through the solar corona and to explore what accelerates the solar wind as well as solar energetic particles.

The spacecraft speed is so fast, at its closest approach it will be going at approximately 430,000 miles (692,000 km) per hour. That’s fast enough to get from Washington, D.C., to Tokyo in under a minute.

NASA named the spacecraft the Parker Solar Probe in honor of astrophysicist Eugene Parker. This was the first time NASA named a spacecraft for a living individual. In this photo, Eugene Parker, professor emeritus at the University of Chicago, visits the spacecraft that bears his name on October 3, 2017. Engineers in the clean room at the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, where the probe was designed and built, point out the instruments that will collect data as the mission travels directly through the sun’s atmosphere.

To perform its investigations, the spacecraft and instruments will be protected from the sun’s heat by a 4.5-inch-thick (11.4 cm) carbon-composite shield, which will need to withstand temperatures outside the spacecraft that reach nearly 2,500 degrees Fahrenheit (1,371 degrees C). This heat shield will keep the four instrument suites designed to study magnetic fields, plasma and energetic particles, and image the solar wind, at room temperature.

Send your name to the sun, via a microchip installed on NASA’s upcoming Parker Solar Probe mission. Submissions will be accepted until April 27, 2018.

Sources -

1. NASA
2. EarthSky.org

China's Tiangong-1 space station will crash to Earth within weeks

The Tiangong-1 space station, which is expected to come crashing to earth within weeks

China’s first space station is expected to come crashing down to Earth within weeks, but scientists have not been able to predict where the 8.5-tonne module will hit.

The US-funded Aerospace Corporation estimates Tiangong-1 will re-enter the atmosphere during the first week of April, give or take a week. The European Space Agency says the module will come down between 24 March and 19 April.

In 2016 China admitted it had lost control of Tiangong-1 and would be unable to perform a controlled re-entry.

Aerospace Corporation said there was “a chance that a small amount of debris” from the module will survive re-entry and hit the Earth. If this should happen, any surviving debris would fall within a region that is a few hundred kilometers in size. Aerospace Corporation also warned that the space station might be carrying a highly toxic and corrosive fuel called hydrazine on board.

The module is expected to re-enter somewhere between 43° north and 43° south latitudes. The chances of re-entry are slightly higher in northern China, the Middle East, central Italy, northern Spain and the northern states of the US, New Zealand, Tasmania, parts of South America and southern Africa. However, the chance of debris hitting anyone living in these nations is tiny.

In the history of spaceflight no known person has ever been harmed by reentering space debris. Only one person has ever been recorded as being hit by a piece of space debris and, fortunately, she was not injured.

Tiangong-1’s descent had been speeding up in recent months and it was now falling by about 6km a week, compared with 1.5km in October. It was difficult to predict when the module might land because its speed was affected by the constantly changing “weather” in space.

A chart showing the descent of the Tiangong-1

The Tiangong-1 or Heavenly Palace lab was launched in 2011 and described as a potent political symbol of China – part of a scientific push to become a space superpower. It was used for both manned and unmanned missions and visited by China’s first female astronaut, Liu Yang, in 2012.

Liu Yang, a Chinese pilot and astronaut who served as a crew member on the space mission Shenzhou 9. On 16 June 2012, Liu became the first Chinese woman in space.

In 1991 the Soviet Union’s 20-tonne Salyut 7 space station crashed to Earth while still docked to another 20-tonne spacecraft called Cosmos 1686. They broke up over Argentina, scattering debris over the town of Capitán Bermúdez.

Soviet orbital station Salyut 7

Nasa’s 77-tonne Skylab space station came hurtling to Earth in an almost completely uncontrolled descent in 1979, with some large pieces landing outside Perth in Western Australia.

Skylab Orbital Workshop in Earth orbit 

Fragment of Skylab recovered after its re-entry through Earth's atmosphere

Sources -

1. The Guardian - Science
2. Wikipedia