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LED Lighting: Blue + Yellow = White

Giving LEDs the blues was the key to replacing the incandescent bulb

4 min read
LED Lighting: Blue + Yellow = White
Illustration: Frank Chimero

Back in the 20th century, just about the only LED you normally saw was the one that lit up when your stereo was on. By the noughties, tiny light-emitting diodes were also illuminating the display and keypads of your mobile phone. Now they are backlighting your netbook screen, and soon they’ll replace the incandescent and compact fluorescent lightbulbs in your home.

This revolution in lighting comes from the ever-greater bang the LED delivers per buck. With every decade since 1970, when the red LEDs hit their stride, they have gotten 20 times as bright and 90 percent cheaper per watt; the relation is known as Haitz’s Law, and it applies also to yellow and blue LEDs, which were commercialized much later.

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Paying Tribute to Computer Science Pioneer Frederick Brooks, Jr.

He helped develop the IBM System/360 and its operating system

3 min read
portrait of an elderly man in a a red tie and blazer with a bookcase in the background
University of North Carolina

Frederick P. Brooks Jr., a prolific computer scientist and longtime professor of computer science, died on 17 November at the age of 91.

While working as a project manager at IBM in the 1960s, the IEEE Life Fellow led the development of the System/360 computer family. It was the first vertically compatible family of mainframe computers. Brooks also developed IBM’s OS/360, the world’s largest software project at the time. He is credited with coining the term computer architecture, which is used to describe how hardware and software are organized to make up a computer system and the operations which guide its function. He wrote The Mythical Man-Month, a book of essays published in 1975 that detailed lessons he learned from challenges he faced while developing the OS/360.

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How to Stake Electronic Components Using Adhesives

Staking provides extra mechanical support for various electronic parts

2 min read
Adhesive staking of DIP component on a circuit board using Master Bond EP17HTDA-1.

The main use for adhesive staking is to provide extra mechanical support for electronic components and other parts that may be damaged due to vibration, shock, or handling.

Master Bond

This is a sponsored article brought to you by Master Bond.

Sensitive electronic components and other parts that may be damaged due to vibration, shock, or handling can often benefit from adhesive staking. Staking provides additional mechanical reinforcement to these delicate pieces.

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