How to fix a dead hard drive?

WHAT DO YOU you do when your HD crashes and you don't want to spend thousands of dollars on a professional recovery service? You do it yourself, and with any luck, it will work.

Scott Moulton of Forensic Strategy Services went through the process of trying to pull things off a 'dead' HD, focusing mainly on a few things that are not painfully obvious.

The first thing is that in his view, about 85% of the dead drives are due to software, not hardware. This can be fixed with a bunch of tools, mounting in a different OS, using a LiveCD, or simply trying it in a different version of the OS itself. There are tons of tools, ranging from really expensive to free to help you here, try them all if you need to.

The other 15% is mechanical, and that is where the problems come in. 10% tends to be the electronics on the bottom, 4% are the heads or platters, and about 1% is the motor. Because the PCB on the bottom of the drive is usually held on by a bunch of screws and not soldered to anything, replacing it is an easy thing to do. Physically swapping the electronics is something a beginner should be able to accomplish.

The problem is that those electronics tend to change on a regular basis, be it the PCB and components, or the firmware, and it does so without any warning. Because the drive is a self-contained unit, who cares what happens on the inside. If you are going to swap PCBs, you need a drive date coded within two months of the dead one, less if you want to be safe. Basically, if you want to do electronics, time matters.

The heads and platters that make up most of the rest are much more tricky. If you have ever opened up a HD, you have seen the heads on an actuator arm, and the platters. If you have one platter, you are in pretty good shape, you can take it out, put it in a different drive, and still have a slim chance of it working. If you have multiple platters, you can not take them out and have any realistic chance of ever recovering your data.

This is because the tracks on the hard drive are placed on at the factory, and you can't modify them. Instead of the old way of doing things, stepper motors moved a head a certain measured distance, the newer way is that the tracks are all encoded with their location. The heads move a bit, and then read where they are. If they need to keep going they do, if not, they start reading data.

The platters are therefore hard encoded with locations, and if you unscrew the spindles, there is nothing holding the platters in alignment. If you free them, you simply have no way of realigning them. Since a sector is written across platters, any misalignment will kill all data on the drive. This means if your motor goes, the last 1%, and you have more than one head, game over. If there are multiple platters, you simply leave them there, anything else is fatal.

This leaves you with moving heads. Simply put, this is a problem that is solvable, but takes very steady hands as long as the platters themselves are undamaged. The way you check this is opening the case and checking the platters for visible damage. If there is nothing visible, check the little air filter, if there is silver on it, once again, game over. If the platters are OK, time to swap heads and pray.

Overall, fixing a hard drive comes down to software tools, and then rarely hardware swaps. If it is hardware, then you are usually looking at a board swap, and barring that, things get messy. In any case it is doable to fix things yourself, but be prepared to break a few drives. Experimentation on non-critical data is recommended, try it and have fun.

How many 'Threads' you have?

Multithreading represents the ability for the computer to execute several things at once. Like multitasking really, except multitasking generally refers to the ability to run multiple programs at the same time, while multithreading refers to the ability for a single program to execute multiple “things” at the same time.

The need for multithreading ranges from simple necessity to “luxuries” such as
enhancing the user’s experience.

The need for multithreading ranges from simple necessity to “luxuries” such as enhancing the user’s experience. On the need-side, consider the core Windows operating system and how it executes programs. Without multithreading or multitasking, I would not be able to run Word and open the Windows start menu at the same time. However, that is not an aspect that many developers (besides those working at Microsoft perhaps) worry about. What is more interesting, for instance, is Word’s ability to run the spelling checker in the background while I type my article. I do not have to stop writing to run the spelling checker, nor does the spelling checker interrupt my flow of work in any way. I can simply type away on the main thread, and the verification of my input is performed on a secondary (probably lower priority) thread.


The same applies to practically all applications available today. Often, developers tell me they do not believe they need multithreading because they only write business applications. I have to admit that I do not quite follow their argument. Business application can benefit from multithreading in many ways. For instance, a business application loads data. Whenever data operations may take a while, threading is beneficial, because without threading, the application appears to be hung. Windows flags it as “not responding,” which may result in the user being annoyed (at best) or inappropriately terminating the application (at worst). So which data operations could potentially take a while? All of them! Even very fast data operations may encounter scenarios where the database server is too busy to perform the operation speedily. Or perhaps the server is blocking data access due to another ongoing operation. Furthermore, data processing speed also depends on bandwidth. Unknown components such as Internet connections may result in utterly unpredictable performance results. Modern applications need to be able to handle such situations gracefully.

Semantic Web

The Semantic Web proposes to help computers "read" and use the Web. The big idea is pretty simple -- metadata added to Web pages can make the existing World Wide Web machine readable. This won't bestow artificial intelligence or make computers self-aware, but it will give machines tools to find, exchange and, to a limited extent, interpret information.
It's an extension of, not a replacement for, the World Wide Web.

Anakin Skywalker is Luke Skywalker's father.

It's easy for you to figure out what this sentence means -- Anakin and Luke Skywalker are both people, and there is a relationship between them. You know that a father is a type of parent, and that the sentence also means that Luke is Anakin's son. But a computer can't figure any of that out without help. To allow a computer to understand what this sentence means, you'd need to add machine-readable information that describes who Anakin and Luke are and what their relationship is. This starts with two tools -- eXtensible Markup Language (XML) and Resource Description framework (RDF).

That probably sounds a little abstract, and it is. While some sites are already using Semantic Web concepts, a lot of the necessary tools are still in development.

Read More...

AJAX - new buzz word in web technology

Ever thought of a web page working like a desktop application, not keeping you staring at the Hour-Glass icon/blank page for each interaction with the server? AJAX is the perfect solution. This is going to change the whole web apps world.

AJAX - is the acronym for Asynchronous Javascript And XML. AJAX gains its popularity by allowing data on a page to be dynamically updated without having to make the browser reload the page. This term has been made famous by some of Google's latest web apps. At the top of this list is Google Suggest, which gives you suggestions (go figure) on what you are searching for as you type based on popularity of the search term. If you aren't familiar with Google Suggest, check it out.

Is AJAX a new technology? The answer would be both Yes and No. A proper answer would be a new application of current technologies.

The JavaScript is the real meat and potatoes in AJAX. It handles the change detection, data request and receipt, and placing the data on the page.
for more technical reading...

10 Reasons Not to Buy the iPod

1. Battery replacement. Most of the other portable players let you change their batteries quite easily. Not the iPod.
2. iTunes Music StoreThe biggest plus about the iPod is the iTunes music service. Sadly, for whatever reason, Apple doesn't think India is important enough to have it.
3. Video playback is pretty basic While you can definitely play some good quality video on the iPod, if you want to output it to bigger display (say when you're traveling and your hotel has a nice big-screen TV), then you gotta buy some expensive accessories!
4. Shifting songs via iTunes is a PAINWhy should you be limited to shifting songs only through iTunes? Every time you get a new song from somewhere, you first need to add it to your iTunes library. Only then can you move it to your iPod.
5. The photo feature is sillyWhile most portable players out there let you copy images through direct drag and drop, iPod does it differently. It converts and optimizes each photo into a proprietary format. This is pretty stupid because if you want to actually SHARE your photographs (like leave a copy behind), you'll need to carry the original JPEGs separately. Also, you can't directly view these JPEGs on the iPod. Pretty dumb if you ask me!
6. Doesn't play FMFM is no more the boring monotonous A.I.R variety. With airwaves opening up and cities getting up to 6 radio stations, having FM is a good thing and every competing portable media player out there today incorporates FM
7. Slow interfaceDespite the Broadcom chip inside and Apple's claims about how great its hardware is, watching videos and forwarding/skipping through them leaves the hardware quite breathless and can be irritating at times.
8. Scratch magnetThe shiny black surface of the iPod (Nano and 5th Gen) gets scratched even if you keep it inside its inadequate cover. The scratching can get so bad that the screen display becomes 'un-viewable', which beats the whole point of having the device!
9. It syncs to just one PCEach iPod can be synced to just one PC at a time. This means that if you have synced it to your desktop, it won't work with your notebook, unless you re-sync it, which will then result in a 'remove-all previous songs' accident. What a hassle!
10. Everyone has oneYeah, I accept it looks pretty cool and is real slick, but everyone has one. Do you really want to be a part of the herd?

Bill Gates wishes he wasn't richest in world

Microsoft Corp. Chairman Bill Gates said he wished he were not the world's richest man.
"I wish I wasn't. There is nothing good that comes out of that," said Gates, whose personal fortune has sunk by billions since last week when the software giant disappointed investors by saying new investments would crimp earnings.
The corporate leader who made Microsoft into the world's largest software maker -- and who is also one of the biggest philanthropists -- is seen as a man who does not like publicity. He explained that he did not like the attention of being the world's richest.
"You get more visibility as a result of it," he said during an interview conducted by CNBC reporter Donny Deutsch in front of a crowd of people attending a Microsoft advertising event.
Read More...

Hospital PCs are source of infection

Computer keyboards used in hospitals are a reservoir for bacteria that staff could pass to patients and need to be disinfected every day, a new study warns.

Researchers collected samples from 25 computer keyboards at various locations inside University of North Carolina hospitals and found that each keyboard was infected with at least two types of bacteria, reports the science portal HealthCentral.

William A. Rutala at the University of North Carolina Health Care System and other researchers said every keyboard tested positive for coagulase-negative staphylococci, a major cause of bloodstream infection in hospitalised patients. They also found 13 other types of bacteria on the keyboards. The researchers also tested different types of disinfectant wipes to clean the keyboards.

Read More...