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Edisi April 22, 2001
Dari Redaksi
Rekan-rekan Alumni
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Selamat berakhir pekan.GOLF
Get a grip on your swing
--by Johnny Miller, NBC Sports
Note: The following segment first appeared during NBC's broadcast of the 2001 Bay Hill Invitational on March 18.
The last couple years I've been playing a lot of golf with amateurs because I'm not playing much competitive golf these days. I've noticed a couple little problems with most players' grips. Sometimes I'll see the Vs formed by their thumbs and index fingers pointed at their nose, or too far over to the right, or two different directions. That's not the way the pros grip their clubs.
I'm going try and show you a typical PGA Tour grip.
I've marked my glove hand and right hand so you can see the Vs better. Put your left hand on the club so the V is pointing just about at your right ear. The V of the right hand should match. On the LPGA Tour, it's a little farther over to the right. The V is pointed at the right shoulder.
This is a neutral position, which aligns your shoulders, elbows and everything in good synchronization and allows you to make a level turn and put a nice, neutral hit on the ball at the bottom.
One last point regarding the grip: don't grip it so darn tight. Grip it loose enough that you can feel the golf club, feel the shaft, get a nice rhythm in your swing and make it more effortless.
Work on those couple things and you'll find better results with your game.
BOWLING TIPS
EQUIPMENT
First, the equipment. Equipment should fit you perfectly. It can mess up your hand later in life if you don’t size it right. Now there are three types of grips, the conventional, the semi-fingertip, and the fingertip. The conventional grip is for most beginning bowlers. The semi is almost out. It can be very hard to put your hand in the same spot every time. The fingertip is for advanced bowlers. In the conventional grip your thumb goes in all the way and your fingers go in all the way. In the semi grip your thumb goes in all the way and your fingers go into the middle between the first and second nuckle. Last, the fingertip. In the fingertip your thumb goes in all the way and your fingers go to the first nuckle. Their is also a fingertip grip where you don’t put in your thumb. I do not recommend this because it makes it hard to keep control.Next, the ball to use for the lane conditions. On oily lanes I recommend a urethane ball or dull reactive resin. This is because one of these ball will catch a lot sooner than a shiny. Shiny balls are usually used for dry and medium lanes. There is also the difference between reactive resin and urethane. Reactive resin hits harder and makes more of a snap. A urethane makes more of a half circle. Urethane hooks sooner but does not snap very hard. Urethane keeps hooking though unlike a reactive resin. Their are a couple other kinds of balls too, plastic and polyester. Plastic and polyester balls are used for beginners and sometimes for spare balls. This is because a plastic or a polyester doesn’t hook. This will take the place of a reactive resin or urethane for a right-hander’s ten pin or six.
FAMOUS QUOTES
If you want happiness for an hour, take a nap.
If you want happiness for a day, go fishing.
If you want happiness for a year, inherit a fortune.
If you want happiness for a lifetime, help somebody.
(Chinese proverb)
KESEHATAN
DIABETES
Diabetes is a disorder of metabolism--the way our bodies use digested food for growth and energy. Most of the food we eat is broken down by the digestive juices into a simple sugar called glucose. Glucose is the main source of fuel for the body.
After digestion, the glucose passes into our bloodstream where it is available for body cells to use for growth and energy. For the glucose to get into the cells, insulin must be present. Insulin is a hormone produced by the pancreas, a large gland behind the stomach.
When we eat, the pancreas is supposed to automatically produce the right amount of insulin to move the glucose from our blood into our cells. In people with diabetes, however, the pancreas either produces little or no insulin, or the body cells do not respond to the insulin that is produced. As a result, glucose builds up in the blood, overflows into the urine, and passes out of the body. Thus, the body loses its main source of fuel even though the blood contains large amounts of glucose.
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KOMPUTER
PC MAINTENANCE
The home computer is a large investment and as such should receive some basic attention on your part. The PC is a very sophisticated device, however it is vulnerable to dust, dirt, tobacco residue, and a variety of other household grime in many critical areas, the monitor, the mouse, the keyboard, the power supply, and the central processor (CPU) to name a few. Dust and dirt can jam your keyboard switches, foul the read/write heads on your disk drives or the laser pickup on your CD-ROM, and can even cause your power supply to overheat. Smoke and dust degrade the quality of the display on that super Monitor and can even cause intermittent connections in your computer. These valuable tools should be cleaned periodically to decrease the probability of system failure.
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AURORA
The northern and southern lights, or auroras, are caused by a gigantic, magnetic wrestling match that unleashes not solar, but earthly particles, to create the brilliant night displays, scientists said Thursday.
Using data from NASA and Japanese spacecraft, scientists with the International Solar-Terrestrial Physics program (ISTP) say they are the first to find direct evidence to settle a 50-year-old controversy over the source of auroras.
The process relies, they say, on "reconnection," a union of solar and Earthly magnetic fields that lets the solar wind -- a flow of charged particles from the sun -- punch through sections of the Earth's magnetic shell.
That process dices up magnetism into energy particles that become the space weather storms known as the northern and southern lights.
"Reconnection is the fundamental process for transferring and exchanging energy in the sun-Earth system," said Atsuhiro Nishida, a researcher with the Japan Society for the Promotion of Science. Nishida also is with the ISTP program.
"Reconnection on the dayside of Earth is critical for allowing solar-wind energy to come into the magnetosphere. Nightside reconnection is critical for the transfer of that energy down to the atmosphere."
Data settles debate
Until recently, scientists disagreed about the cause of auroras, with some promoting the theory of reconnection. But recently, NASA's Polar spacecraft flew through a region on the sunlit side of Earth to witness reconnection directly. Also, scientists looked at data from Japan's Geotail spacecraft, which passed through Earth's magnetic field and found the area on the nightside where reconnection occurs. That gave scientists the data they needed to correlate reconnection with auroras.
The finding has business and lifestyle implications, as solar weather can disrupt radio communications, spacecraft operations and power grids on Earth. Extreme solar weather can harm astronauts in space. Understanding how solar weather works could help us avoid scrambled communications and avert disaster.
Scientists think reconnection could be the key to understanding solar flares and other solar eruptions, as well as the source of galactic X-rays beyond our solar system and the process of nuclear fusion.
Torn cocoon
Before this finding, many believed auroras came about when the particles spewing from the sun to Earth charged through our planet's atmosphere near the North and South Poles.
In fact, the sun provides the energy, not the particles, Nishida said. The particles were already there, trapped in Earth's magnetosphere. And the process starts not at the poles but at "reconnective regions" elsewhere around the globe.
To understand that, think of Earth's magnetic shell, or magnetosphere, as a cocoon around the planet, said Jack Scudder, a University of Iowa physicist who studies data from the Polar spacecraft.
"There are often times when the solar wind creates tears in this cocoon, allowing charged particles and energy from the sun to enter the space around Earth," he said. "This tearing -- reconnection -- is what we directly observed with Polar."
Once the tears occur, the solar wind combines with the magnetosphere to overload the system of magnetism nearby. That energy excites nearby particles and causes another bounce and reconnection of magnetic fields that shoot energy to the auroral zones at the Earth's poles and into its radiation belts.
In the past eight years, Geotail has studied Earth's magnetosphere in search of colliding and combining solar and earthly magnetic fields -- reconnection. Geotail's success has helped scientists pinpoint the reconnection area -- about 85,000 to 96,000 miles (140,000 to 160,000 kilometers) downwind of Earth.
TOP MODEL
BELINDA
DIRGANTARA
P51 Mustang
USA. 1944
This best known US fighter of WWII was built to British requirements. The British reluctantly accepted North American's proposal to design a new fighter for them, instead of license-building P-40's, and the USAAF was at first not interested at all. The P-51 was a clean and very refined design, with a laminar flow wing and carefully positioned radiator bath. The early P-51, with Allison V-1710, engine, was an excellent low-altitude reconaissance fighter, but had low performance above 15000ft. After reengining with the R.R. Merlin, the P-51B was one of the best fighters of WWII. It proved to be the ideal fighter to escort the bomber force on the long missions over Germany. The P-51D sacrificed some speed for the introduction of a 'bubble' hood, offering much better view. The P-51F, G and J versions were lightweight developments, with only a superficial resemblance to the original Mustang; the P-51H was more directly related to the P-51D, but powered by the more powerful V-1650-9 engine. After WWII, the P-51D played a very important role as fighter-bomber in Korea. 14819 built.Type: P-51A
Function: fighter
Year: 1943
Crew: 1
Engines: 1 * 1200 hp Allison V-1710-81
Wing Span: 11.28 m
Length: 9.83 m
Height: 3.71 m
Wing Area: 21.65 m2
Empty Weight: 3110 kg
Max.Weight: 4812 kg
Speed: 628 km/h
Range: 2011 km
S37 BERKUT
Russia, 2000
Sukhoi Fifth-generation Fighter Philosophy
The FSW is a better performer at high angles of attack in post-stall manoeuvring much needed in close-in dogfight. The fact that Simonov had chosen FSW for his fifth-generation fighter once again confirms Sukhoi's commitment to the superagility as a crucial requirement for the next generation air-superiority fighter. This approach, so much different from western concepts of stealth, supercruise and BVR engagements, was taken to the limits in Su-37. The FSW S-32 fitted with TVC expected to outperform its stalemate in close-in dogfight involving post-stall flight regimes. Having the edge in manoeuvring, the S-32 is clearly catching up in stealth with US and European new-generation fighters. However even with its internal weapon bay and RAM coating, the new Sukhoi is a very different concept than F-22. The heavy accent on RAM rather than radar absorbing structures (RAS) is obvious. The reason for such attitude is not clear, although a combination of the technology limitations and operational doctrine is most likely candidate. The major components of radar stealth -- RAM coatings and surface quality -- are subject to the production and maintenance tolerance as it was shown by USAF F-117 and B-2 operational experience. Untightened screws, scratches or unfastened access panels were known to greatly deteriorate the RCS of the aircraft, reducing the engineering efforts put into aircraft design. It remains to be seen how Sukhoi will overcome the looser production standards of the Russian aircraft plans.The Afghanistan experience where Sukhoi's encountered a thread of the shoulder launched infrared homing surface-to-air missiles such as Redeye, Stinger and SA-7, forced Sukhoi team to work on the reduction of the infrared signature of the Su-25. The results materialized in the Su-25T development -- Su-25TM (Su-39 in Sukhoi's nomenclature). The installation of the intake cones hiding the turbine blades and efficient mixing of the exhaust with cold air reduced the IR signature of the Frogfoot from front and rear aspects. This fourfold reduction at expense of 2% lower SFC is indeed an impressive achievement. Further experiments with low visibility involved the advanced Flanker development prototypes, aircraft of 700 (Su-35,-37) and 600 (Su-30) series. These fighters wear eye catchy new camouflage schemes designed to reduce the visual signature of the aircraft on the ground and in the sky. One of the most interesting examples of Sukhoi experiments was a scheme applied to 701, designed to deceive space based optical systems. Some effort was directed in reduction of the radar cross sections of advanced Flankers as well. The Su-34,-32FN have optimized radar random shape, lack variable geometry intakes and were reported to have partial RAM coating. Recently Sukhoi stated that basic export models of Su-30MK can be treated with RAM to fulfill customer requirement for a lower RCS aircraft. Clearly benefitting from previous research, the S-37 prototype relies heavily on the Sukhoi's state of the art low observable technology. The forward swept wing, a conformal underfuselage weapon station(s), use of RAM and the inward-canted tailfins, suggest a further reduction of the aircraft radar signature down from similarly sized Flanker's 3-5 sq m. The extend of the reduction of the IR signature of the S-37 exhausts will depend on the choice of the trust vectoring nozzle. The F-22 type flat 2D nozzle can give a better results while 2D nozzle might contradict to Simonov's superagility ideas favouring 3D exhaust. The Saturn-Lulka was reported to work on reduction of the IR signature of the axi-symmetric trust vector controlled (TVC) Al-37FU power plant on non-afterburning regimes.
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