Wednesday, October 29, 2008

Electric Cars

An alternative of fuel car that shows up in the news all the time is electric car. It is a type of car that utilizes electric motors and motor controllers instead of an internal combustion engine (ICE) or gasoline engine.

There are a lot of differences between gasoline and electric cars:
  • The gasoline engine is replaced by an electric motor.
  • The electric motor gets its power from a controller.
  • The controller gets its power from an array of rechargeable batteries.
  • A gasoline engine, with its fuel lines, exhaust pipes, coolant hoses and intake manifold, tends to look like a plumbing project. An electric car is definitely a wiring project


Other examples of rechargeable electric vehicles are ones that store electricity in ultracapacitors, or in a flywheel. Vehicles using both electric motors and other types of engine are known as hybrid electric vehicles and are not considered pure electric vehicles (EVs) because they operate in a charge-sustaining mode. Hybrid vehicles with batteries that can be charged externally to displace are called plug-in hybrid electric vehicles (PHEV), and are pure battery electric vehicles (BEVs) during their charge-depleting mode. Electric cars or vehicles include automobiles, light trucks, and neighborhood electric vehicles.

Electric car using DC motor


A simple DC controller connected to the batteries and the DC motor. If the driver floors the accelerator pedal, the controller delivers the full 96 volts from the batteries to the motor. If the driver take his/her foot off the accelerator, the controller delivers zero volts to the motor. For any setting in between, the controller "chops" the 96 volts thousands of times per second to create an average voltage somewhere between 0 and 96 volts.

Electric car using AC motor


An AC controller hooks to an AC motor. Using six sets of power transistors, the controller takes in 300 volts DC and produces 240 volts AC, 3-phase. The controller additionally provides a charging system for the batteries, and a DC-to-DC converter to recharge the 12-volt accessory battery.

Video of electric car vs Ferrari

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Saturday, June 21, 2008

How to Keep Your Laptop from Getting Stolen

By Erin Kandel

Thousands of laptops are stolen each year in the United States, and many of those thefts take place on college campuses. To make sure your beautiful, brand-spankin'-new portable doesn't become just another sad statistic, we've outlined some essential advice to help you keep thieves from successfully snatching your PC. We'll also give you some useful tips for safeguarding your data, in case your computer does go missing.

DON'T LEAVE IT ALONE

Never leave your laptop by itself in any public place: the library, the coffee shop, the dorm-room common area, anywhere. Once your machine is out of your sight, or even out of your reach, it's up for grabs by thieves. And don't even think about asking that random student next to you to keep an eye on it while you step out; you never know who might have sticky fingers. We'd even balk at asking friends to stand guard—you can't trust anyone besides yourself to maintain the necessary vigilance to keep your machine from getting stolen.

GO ON LOCKDOWN

Your laptop is like your bike: It needs to be locked up. Companies like Kensington and Targus sell a variety of keyed and combo cable locks that attach to a notebook's lock slot. These lightweight locks don't offer enough muscle to stop serious thieves (specifically, the wire-cutter-toting type), but at the very least, they're a visible deterrent for those who might try for a quick nab while your back is turned. We like the $24.99 Kensington ComboSaver Combination Portable Notebook Lock. At 8.8 ounces, it won't weigh down your already-book-laden backpack, and its retractable cable makes it a cinch to stow. (Kensington also offers a Lock Slot Adapter Kit for laptops without slots.) To take your defense up a notch, opt for a more durable locking system, such as Belkin's $24.99 Bulldog Security Kit. Though not as portable as standard cable locks, it has steel anchor plates, a heavy-duty key lock, and an aircraft-quality cable that will better withstand dogged laptop pinchers. Best of all, it comes with a $500 anti-theft warranty.

Common-Sense Tip: When in a public place, lock your laptop to something secure and immovable, such as a pole, column, or the leg of an unliftable table or desk. (We recommend doing this when leaving your laptop in your dorm room, as well.) Looping your cable lock around the leg of a chair won't really cut it: All a thief has to do is lift, grab, and run. Also, having a lock doesn't mean you shouldn't heed our first piece of advice: Leaving your system unattended will only give thieves more opportunities to try to break or pick your primary line of defense.

PACK IT SAFE

For an extra layer of protection on the road, look for laptop bags and backpacks with built-in anti-theft features. Ben 222c eath its nylon exterior, the $119.95 PacSafe Couriersafe 100 laptop bag is lined with stainless steel wire to prevent knife-wielding burglars from slicing through to your computer. It also has lockable zippers, a slash-proof, cable-lined shoulder strap, and a built-in combination lock that lets you anchor the bag to a secure fixture.

SOUND THE ALARM

There's nothing like noise and commotion to blow a sneaky thief's cover, and low-cost laptop alarms offer just that. When connected to one of your laptop's USB ports, the motion sensor-equipped Doberman Laptop Defender SE-0210 will sound a 100-decibel alarm if anyone tries to move your system. Because the device is the size of a credit card, it's easy to carry around. Plus, it charges via USB, so you never have to worry about failing batteries. It's available for $30 from Circuit City.

TRACK IT DOWN

If your laptop does get nicked, you'll have a better chance of getting it back if you invest in tracking-and-recovery software. If your stolen PC is used to access the Web, the software can pinpoint your notebook's location—without alerting the thief. The service will then pass this location information on to local law enforcement, which can then take action to recover your laptop. Among the packages available are Absolute Software's Lojack for Laptops ($50/year), Brigadoon's PC PhoneHome ($30/lifetime), CyberAngel Security ($69.95/year), Inspice Trace ($30/year), XTool's Laptop Tracker ($40/year for the Small Business Edition), and zTrace Gold ($50/year).

ENCRYPT YOUR FILES

Sometimes the data saved on your notebook is as valuable as the system itself. Though it won't stop hard-core hackers, file encryption may protect your files from common laptop thieves. FileVault on Mac OS X lets you encrypt and password-protect everything on your hard drive. (You can set it up in the Security section in System Preferences). In Windows XP and Vista, all you need to do is right-click on the file or folder you want encrypted, select Properties > General tab > Advanced, and then check the "Encrypt contents to secure data" box. For protecting a specific folder or group of files, we also recommend the free utility Truecrypt. It encrypts a custom-size volume with 256-bit Advanced Encryption Standard (AES) encryption, so it's extremely secure. Another option is to buy a portable USB drive with built-in encryption, such as the CMS ABS-Secure Encrypted Backup System.

Common-Sense Tip: Just because someone takes your laptop, doesn't mean you have to lose your data forever. We highly recommend backing everything up regularly with an external USB drive like the Maxtor OneTouch 4 Plus. As for backup software, try the free and easy to use 2BrightSpark Syncback.

http://computershopper.com/feature/how-to-keep-your-laptop-from-getting-stolen
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