Rockets are powerful stuff, and satellites and astronauts experience tremendous G-forces pushing down on them during launch. Your satellite will experience up to 10G (10 times Earths gravity) during launch. It is important to test this. For picosatellite work, it is necessary that your design be able to withstand these forces. To test this, the easiest way is to build a centrifuge. It is also easy to test. Well offer two systemsthe lab-oriented motor centrifuge and a more casual rope centrifuge. Both can reach up to 3G force.
Think of the spinning bucket gimmick. If you tie a bucket to a rope and fill it with water, you can make the bucket swing in a loop-the-loop over your head and not spill, as long as it is spinning fast enough. You need enough spin to counteract the 1G of the Earths pull, so you need a spinning centrifuge of at least >1G.
Most homebuilt centrifuges are used by mad scientists doing medical or chemical studies that require they separate a fluid by density. For satellite building, we can use a far simpler design. Yes, you can actually just spin your satellite in a bucket at the end of a ropeor build a 3G spinning rig using an ordinary electric drill.
Services are among the main building blocks in Android. Unlike an activity, a service doesn’t have a user interface; it is simply a piece of code that runs in the background of your application.
Services are used for processes that should run independently of activities, which may come and go. Our Yamba application, for example, needs to create a service to periodically connect to the cloud and check for new statuses from the user’s friends. This service will be always on and always running, regardless of whether the user ever starts the activity.
Just like an activity, a service has a well-defined life cycle. As the developer, you get to define what happens during transitions between states. Whereas an activity’s state is managed by the runtime’s ActivityManager, service state is controlled more by intents. First, you must create the service. Whenever an activity needs the service, the activity will invoke the service through an intent, as described in Intents. This is called starting the service. A running service can receive the start message repeatedly and at unanticipated times. You can also stop a service, which is called destroying it.
Or, How We Learned to Stop Worrying and Love the Boom (1966)
Coming to New York from the muted mistiness of London as I regularly do, is like travelling from a monotone antique shop to a Technicolor bazaar.
(Kenneth Tynan, Holiday, December 1960)
Ancient elegance and new opulence are all tangled up in a dazzling blur of op and pop … In a once sedate world of faded splendor, everything new, uninhibited and kinky is blooming at the top of London life.
(Time magazine, April 1966)
The first of these comments coincided with the London première of Saturday Night and Sunday Morning, the second appeared just after the New York screening of Morgan. Between the two films, as between these two assessments of London, there is a world of difference and a whirl of indifference. Something has changed in a country and its cinema. As an admirer of High Noon said when he saw Born Free, a funny thing happened on the way to the Foreman.
The word ‘renaissance’ is freely bandied about at home and abroad. The British cinema is ‘undergoing a renaissance’, Alberto
Even the most careful shoppers sometimes change their minds about purchases they have made. This lesson presents words to know when you must return merchandise.
A. Circle a letter to show the meaning of the boldfaced word or phrase.
1. Elmer realized the coffee he’d purchased was stale. He went back to the store for a refund.
a. a new package of coffee b. his money back c. an apology
2. Aya took a bathing suit back to The Big Wave shop. She hoped to exchange it for one that fit better.
a. trade, replace
b. sell c. get money back
4. When Kenji shops, he likes to use his credit card. If he returns an item, he can get a credit to his account. a. The charge for the purchase is subtracted from the buyer’s credit card account. b. The person’s account is billed double for the purchase. c. The store refunds the amount of the purchase in cash.
3. Aya could not find another suit she liked. She got a store credit to use at a future time. a. a gift certificate good at any clothing store