Saturday, January 12, 2008

Solar Energy as power source


Solar Energy Powers South African Schools

Photovoltaic systems provided by Isofoton, of Spain, and funded by the European Union, have been installed in 1000 rural schools throughout South Africa. These schools have never been served by grid electricity, so this new power source will enable the schools to hold evening classes which will allow for an expanded educational system and for use of modern educational media tools, including much audio-visual equipment also installed as part of the program. Each school's power potential will be 880 Wp.

Difference between DVD-R, DVD+R, DVD+RW, DVD-RW


There's DVD+R, DVD+RW, DVD-R, DVD-RW, and even DVD-ROM! So what's the difference between all of these different names, aren't all DVDs the same? Well, it's not quite that simple.

Let's first start with the most obvious difference: some have R and some have RW. The "R" stands for readable, while the "W" stands for writeable.

The main difference between DVD-R and DVD-RW, or DVD+R and DVD+RW is that the R disc formats can only be written to once, and then it is only readable and can’t be erased for the rest of its digital life. While RW discs are can be written to and erased many times, they are both readable and writeable.

"R" discs are perfect if they are only needed to be written to once, such as giving some files to a friend or transferring them between PCs. "RW" discs have their strength in the ability to be used many times over, which is great for routine system backups, etc. And naturally, the RW discs are slightly more expensive than the R discs, but you'll have to decide if the trade offs are worth the money.

Now, onto the difference between DVD-R and DVD+R. As I just described above, DVD-R & DVD-RW are sister discs, the difference being one is writeable once, while the other is writeable multiple times. The same thing is true for DVD+R & DVD+RW. So the question is, what's the difference between the plus and minus?

In order to explain this we must take a trip back in time. When DVDs were first being developed, there was no industry standard. Multiple companies were competing to develop what they hoped would be the dominant form of the future.

The DVD-R DVD+R difference can easily be summarized by the following:

* The DVD-R/RW standard was developed by Pioneer, and is used primarily by Apple and Pioneer. These "minus" discs can only be written to in one layer on the discs surface. In addition, this format is supported by the DVD forum, but is in no way an industry standard. DVD-R/RW discs are cheaper than the "plus" format.
* The DVD+R/RW format is supported by Philips, Dell, Sony, HP, and Microsoft. These discs can be written to in multiple layers, giving them slightly better and more disc storage than the "minus" format. Because of this additional capacity, they are slightly more expensive than "minus" discs.

A couple final things to clear up is the difference between DVD-ROM and DVD+RW, or the other DVD formats I mentioned above. The DVD-ROM drive can only read DVDs, while the other DVD drives can read and write data to DVDs.

And naturally the DVD+RW CD+RW difference can be explained by the "DVD" or "CD" prefix. DVDs, on average, can store up to 4.7 GB of data, while a CD can only store about 700 MB of data, or about 15% of a DVD's capacity. While CDs are slightly cheaper, in my opinion, the benefits of DVDs are much greater.

So now that you've learned about the difference between DVD-R, DVD+R, DVD-RW, DVD+RW, and even DVD-ROM, which one is right for you? The easiest way to determine which is more beneficial is to watch the industry trends. A few years ago all pre-built computers were shipping with DVD-ROM drives. Today, most PCs have a burnable DVD drive.

I feel that the benefits of having a burnable DVD drive far outweigh any additional costs. They store much more data, and they are ideal for storing your home movies to watch on your DVD player.

My advice is to look at DVD burners that support all of the major formats I've mentioned above, DVD-R, DVD+R, DVD-RW, and DVD+RW. While a DVD drive that supports all of these formats may be slightly more expensive, it will allow you to use any type of DVD disc to burn to, and you'll be protected from any industry shifts to one format or the other.

Friday, January 11, 2008

Reboot without rebooting - Winxp System Response

Have you ever been using your computer and your system suddenly stops responding in ways like it if you try to open something it just hangs? One time I tried deleting a folder and it said it was in use, but it really wasn't. If this ever happens to you, you can follow these simple steps to 'reboot' your computer without 'rebooting' it.

Press CRTL + ALT + DEL

Go to the 'processes' tab and click explorer.exe once and then click 'end process'.

Now, click File > New Task and type explorer.exe

Everything should be fine now! If the problem is major, I would recommend actually shutting down then starting up again.