Category: Science

Sir Isaac Netwotn’s three laws of motion. Three states of matter (solid, liquid, gas). We live on the third rock from the sun. Our metric system of measurement uses metre, litre, and gram. Morse code is a reliable system as the signal is made up of only three parts – a long ‘on’, the dash; a short ‘on’, the dot; and an ‘off’ signal. Do you know what SOS means in Morse code?

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Among Many Peoples, Little Genomic Variety

By David Brown
Washington Post Staff Writer
Monday, June 22, 2009

There is a simplicity and all-inclusiveness to the number three — the triangle, the Holy Trinity, three peas in a pod. So it’s perhaps not surprising that the Family of Man is divided that way, too.

All of Earth’s people, according to a new analysis of the genomes of 53 populations, fall into just three genetic groups. They are the products of the first and most important journey our species made — the walk out of Africa about 70,000 years ago by a small fraction of ancestral Homo sapiens.

One group is the African. It contains the descendants of the original humans who emerged in East Africa about 200,000 years ago. The second is the Eurasian, encompassing the natives of Europe, the Middle East and Southwest Asia (east to about Pakistan). The third is the East Asian, the inhabitants of Asia, Japan and Southeast Asia, and — thanks to the Bering Land Bridge and island-hopping in the South Pacific — of the Americas and Oceania as well.

The existence of this ancient divergence has long been known.

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Three’s the Charm: Triple-Frequency Combinations in Future GNSS

by Dr. Andrew Simsky,
Septentrio, Belgium
With the advent of multi-frequency global navigation satellite systems, triple-frequency combinations of measurements shall become available that do not include information on receiver or satellite positions, velocities and clock biases (geometry-free), and no atmospheric delays as well (iono-free). These will offer important applications in future GNSS, in particular in multipath analysis and multi-frequency ambiguity resolution algorithms.

Geometry-free combinations of measurements from the same satellite, such as (Φ1 − Φ2) or (P1 − P2), are used in today’s two-frequency GNSS to estimate variations of inter-frequency ionosphere delays. These combinations also contain information on multipath, which cannot be separated from ionosphere delays if only two frequencies are used.

If the measurements on a third frequency are available, these dual-frequency geometry-free combinations can be combined together to form triple-frequency geometry-free/iono-free combinations, which contain the superposition of multipath and tracking errors for the three frequencies, while ionosphere delays are canceled out.

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Trinary – Brain circuitry findings could shape computer design

Guosong Liu, a neuroscientist at the Picower Center for Learning and Memory at MIT, reports new information on neuron design and function in the March 7 issue of Nature Neuroscience that he says could lead to new directions in how computers are made.

While computers get faster all the time, they continue to lack any form of human intelligence. While a computer may beat us at balancing a checkbook or dominating a chessboard, it still cannot easily drive a car or carry on a conversation.

Computers lag in raw processing power–even the most powerful components are dwarfed by 100 billion brain cells–but their biggest deficit may be that they are designed without knowledge of how the brain itself computes.

While computers process information using a binary system of zeros and ones, the neuron, Liu discovered, communicates its electrical signals in trinary–utilizing not only zeros and ones, but also minus ones. This allows additional interactions to occur during processing. For instance, two signals can add together or cancel each other out, or different pieces of information can link up or try to override one another.

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