Archive for the ‘Science’ Category
Basic Principles Of Theory Of Evolution
Evolution theory teaches that survival is for the fittest living organism.
What is life? What is fit? And what does it mean to survive?
Well, there are many definitions of course. A useful definition, in scientific perspective, is the one that allow us to analyze myriads things with fewest principles. So here they are.
A living organism is a class of objects that share 3 traits.
1. Reproduce. Living organism can make copies.
2. Inherit. Living organism, in the process of reproducing, will inherit traits to the offspring.
3. Mutate. Living organism, in the process of inheriting, will make small mistakes.
That seems like a reasonable definition. If we look most living things around us, like dogs, cats, pigs, birds, fido, virus, etc., they all share those traits.
However, based on those definitions, God is not alive, while computer virus, religious doctrines, ideologies, and ideas are alive.
I don’t think God will mind though. It’s just a definition.
The practical aspect is that we can use evolution theory to explain the sort of humans, cats, dogs, germs, doctrines, ideologies, and ideas that are common nowadays.
Different living organism performs those 3 traits differently. Those living organism that reproduces a lot becomes plenty. Those that reproduced a lot, become common.
That’s the basic of evolution theory.
For example, we see that peacocks tend to have long elaborated tails. From this, we can guess peacocks with long elaborate tail must have made more peachicks. Perhaps, peahen love peacocks with long elaborate tails. It’s true.
Suppose it were true. Then peacocks with longer tails will mate with more peahens. Those happy couples will then produce more peachicks.
Male peachicks will inherit long tails. Female peachicks will inherit preferences for long tail. So, peahens like peacocks with long tail.
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Ball Bearings Are Flat – Another Myth Crushed
What shape are ball bearings? They are shaped like a ball, as everyone knows, right?
The funny thing about what everyone knows is that everyone can be wrong. For instance, everybody thinks that the America’s Cup is an ocean-sailing race, and yet the Swiss managed to win the Cup. For those readers who are geographically-challenged, Switzerland is a land-locked country comprised entirely of mountains.
What does this have to do with ball bearings. Very little, I suspect, but balls have very little to do with ball bearings, either. Ball bearings look more like hula hoops. But don’t try using them for that – you will find them inconveniently heavy and painfully small.
You can view a picture of a ball bearing in the middle of this ball bearing supplier’s page.
So what are those stunted metal tube donuts called ball bearings for anyway? Are they used as a spare wheel? Do they hold in evil shop-floor spirits? No, they help things move more efficiently. In an early demonstration of bearing usage, three ladies pulled a locomotive (It was just a demonstration, not a career development).
Many bearings look very similar, whether they are ball bearings, roller bearings or other bearings. What?! Other bearings?
What is a ball bearing, anyway?
Ball bearings are formed with an outer ring, an inner ring, a cage or a retainer inside, and a rolling element inside, typically a ball (which is why they are called ball bearings). Roller bearings are formed using a roller instead of a ball, which is why they are called roller bearings (Yes, finally something that makes sense!). Other bearings look just like metal tubes, called plain bearings or bush bearings. They look like sawed off pipe or tube (something my metal tube bending client would be turning into architecturally glamorous structural supports).
Artificial Intelligence is 50 years old
Artificial Intelligence as a research field was born in the summer of 1956 during a seminal workshop at Dartmouth College in Hanover, New Hampshire. It was just a year before that when Marvin Minsky, Nathaniel Rochester, Claude Shannon and John McCarthy proposed that they should hold a workshop to put together a roadmap about how to make machines think and learn similarly to humans. The ultimate goal was to discover computational models in order to enable machines to do commonsense reasoning. Today, John McCarthy is rightly considered the father of AI. I should note that the term “Artificial Intelligence” appeared for the first time in the proposal put forth by the previously mentioned scientists. And so this new discipline that would eventually captivate everyone’s imagination was born.
Artificial Intelligence had its ups and downs in the last 50 years. Early success solving small problems in simulation ignited a flurry of predictions about super intelligent machines taking over the world before the coming of the 21st century. Hampered by a lack of a good understanding of how commonsense reasoning works in people and a lack of computational resources, computers being very slow up until the mid nineties, AI research stalled in the 80s. Many people rushed to dismiss it as nothing more than hot air.
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Animals and The Melting Arctic Ice Cap
The arguments for global warming can sound a bit vacuous when discussing temperature changes of only one degree. The impact of the melting Arctic ice cap on animals is much more tangible.
Animals and The Melting Arctic Ice Cap
There is little dispute that the Arctic ice cap is melting. Since 1979, it has definitively shrunk by 20 percent. The issue amongst most people debating global warming is whether this is because of global warming or just a natural cycle of the planet.
From a common sense point of view, it is difficult to imagine global warming is having no impact on the ice caps. The rising temperature of the planet would seem to be a common sense cause of the melting ice. Alas, common sense rarely seems to be used in debates these days.
As the cap melts, the impact on animals in the area is readily apparent. The primary problem is the reduction of habitat. Polar bears are the most obvious animals suffering from this situation. The habitat of the polar bears is the ice flow areas around the edges of the caps. As the caps melt, the flows are disappearing and pulling back to the extent that there is no ice on the shores. The extent of the melting is such that a Russian ship was able to reach the North Pole in 2005 without the use of an ice breaker. This lost habitat is pushing the polar bears to the edge of extinction. Various estimates put the total population at 20,000 and dropping.
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