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Missile Defense

Technology has always found its greatest consumer in a nation's war and defense efforts. Since the last attempts at a "Star Wars" defense system, has technology changed considerably enough to make the latest Missile Defense initiatives more successful? Can such an application of science be successful? Is a militarized space inevitable, necessary or impossible?

Read Debates, a new Web-only feature culled from Readers' Opinions, published every Thursday.

gisterme - 06:25pm Jan 21, 2003 EST (# 7883 of 7899)

From Merriam-Webster:

... os·cil·late Inflected Form(s): -lat·ed; -lat·ing...

...Etymology: Latin oscillatus, past participle of oscillare to swing, from oscillum swing

Date: 1726

1 a : to swing backward and forward like a pendulum b : to move or travel back and forth between two points

2 : to vary between opposing beliefs, feelings, or theories

3 : to vary above and below a mean value

- os·cil·la·to·ry /'ä-s&-l&-"tOr-E, -"tor-/ adjective

Oscillation has been used for centuries to mark time, Robert. A pendulum (in quiet air) oscillates (swings) with constant period in the gravitational field. A gradnfather clock is a gravity-powered oscillator.

In electronic systems one of principal uses for oscillation is also to mark time. The "clock" in your computer is based on a precisely cut crystal or a ceramic resonator. The crystal or resonator in an oscillator have a specific geometry such that they resonate at a specific constant frequency when excited by an electric stimulus. Some of the output energy from the oscillator is "fed back" to continue excitation of the crystal or resonator and thereby sustain oscillation. Just like in the granfater clock. "Clock" speed has tradationally been one of the basic measures of computer capability. The faster the "clock", the faster the computer can execute an instruction. The actual oscillator frequency in a computer is most often an integer multiple of the "clock" frequency.

Another principal use for oscillators in electronic systems is to provide a radio-frequency basis for transmission of lower frequency information. In an AM (amplitude modulation) radio transmitter, an oscillator provides the constant radio frequency (RF) signal that is actually transmitted through space from the transmitter antenna to the receiver antenna. It's called the carrier signal.

The much lower-frequency intellegence such as voice, music or binary data rides on this carrier signal in the form of variations in its amplitude. The transmitter's process of superposing the audio frequency information onto the RF carrier signal is called modulation.

The receiver reverses the process by demodulating the received amplitude-modulated RF carrier signal by removing the carrier and amplifying the audio frequency data that remains. That's what we hear coming out of our radios. There are a number of different methods of modulating and demodulating RF carriers but the purpose of the oscillator remains esentially the same. It's a time standard.

With very few exceptions beyond those two cases oscillation is highly undesirable in electronic systems. It is even less often desirable in mechanical systems. Except for those few special cases, oscillation is considered unstability.

Great engineering effort is expended to assure that electronic and mechanical systems do not contain undesired points of resonance. Otherwise the systems will be unstable and will not work properly.

What do you mean by an oscillatory solution, Robert?

mazza9 - 08:59pm Jan 21, 2003 EST (# 7884 of 7899)
"Quae cum ita sunt" Caesar's Gallic Commentaries

Pardon me, Gisterme but I suspect a typo!

Main Entry: os·cu·late

Pronunciation: 'äs-ky&-"lAt

Function: transitive verb

Inflected Form(s): -lat·ed; -lat·ing

Etymology: Latin osculatus, past participle of osculari, from osculum kiss, from diminutive of os mouth -- more at ORAL

Date: circa 1656

: KISS

Robert always refers to Casablanca. During the 40s a common slang expression was, "Greetings Gate let's osculate!"

Given the backward manner of his posts I wonder if the key to his diplomatic regimen is his "goin' slow" so that he can accomplish a

DERRIERE OSCULATION!

Hey lunar baby! "Greetings Gate wanna osculate?"

almarst2002 - 09:43pm Jan 21, 2003 EST (# 7885 of 7899)

"Americans IN, Germans (and French and Chinese) DOWN and Russians OUT"

That's the essence of a NEW WORLD ORDER - the Anglo-Saxon DOMINATION of the World by means of controling the major energy resources. Slightly (by some 70 years) slowed down during the Cold War.

Now - BACK TO BUSINESS.

But what if China, Russia, India, France and Germany would disagree?

mazza9 - 09:47pm Jan 21, 2003 EST (# 7886 of 7899)
"Quae cum ita sunt" Caesar's Gallic Commentaries

Disagree? With what, pray tell?

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