For 'U'

Kumarakom: Capital of God’s own country!

2011-06-21T10:15:00.000-07:00

By Clint Thomas | Yahoo! India News – Tue, Jun 21, 2011

By early June the southwest monsoon breaks and there are three months of wind and water with short spells of sharp, glittering sunshine that thrilled children snatch to play with. The countryside turns an immodest green. Boundaries blur as tapioca fences take root and bloom. Brick walls turn mossgreen. Pepper vines snake up electric poles. Wild creepers burst through latente banks and spill across the flooded roads. Boats ply in the bazaars…thus Arundhati Roy begins her Booker Prize winner – The God of Small Things. Although the novel - which is set in Ayemenem village adjoining Kumarakom - does not render the unspeakable beauty of Kumarakom, aren’t the aforementioned words enough to lure you to the most beautiful place in Kerala (arguably)? And If I say Kumarakom is the capital of the God's own country, will you disagree?

Well, honestly, this is my fourth trip to Kumarakom, with an intention of doing a photoblog on Yahoo! Strangely, it had been raining all these four times, maybe, to make me realize that the beauty and majesty of Kumarakom are at its best during monsoon.

And this time, I’m in a houseboat, the perfect place for chilling out -and much more ;-). Houseboats are big barges with five-star amenities –air conditioned bedrooms with contemporary bathrooms, modular kitchens that prepare the choicest Kerala-style food, home theatre and whatever else you want. Some of them have as many as five bedrooms, some have conference halls and some are even double-storied.

Every here and there you see a fisherman, hounding for Karimeen (pearl spot). The boat captain excitedly explained to us four different methods to catch a pearl spot fish and how clinically they do it. Interesting!

At the prow of the houseboat sits Sreehari, 15, after whose name the boat is named. He doesn’t just share his name with the boat, but he owns it! The young guy too has his share of knowledge to impart – about Tiger Prawns, another taste of the Kumarakom. He flashes his torch into the water, toward the stone wall of the canal’s side and I see two small bulbs flashing between two stones. And he says those are the eyes of a Tiger Prawn. Wow!

Before I clicked this photo, it never occurred to me that lightning is the best source of light for night photography. Yes, this photo was clicked at 11:40 pm, there was lightening and the photo came out like this.

It may be the company of boatmen, the palatable Karimeen (pearl spot) fry, mouth-watering tiger prawns curry, a bottle of chilled beer from the boatmen’s icebox, a romantic night with your other half, or the cruise across the Vembanad Lake, Kumarakom guarantees you something to cherish for a lifetime.

India won ICC world cup 2011

2011-04-05T07:05:00.000-07:00

By defeating Sri Lanka , India emerged the champions of international cricket defeating Sri Lanka by 6 wickets. It was all cheers to skipper Mahendra Singh Dhoni, who won the man of the match for his unbeaten 91 and Gautam Gambhir scoring 97.

Chasing 275, India managed to score the runs in 48-2 overs inspite of Sachin and Sehwag falling early. Yuvraj Singh, who won four man of the matches in the tournament, was adjudged man of the series.

Indians who are the number one in Test cricket are now the number one in One Day cricket too.

All-rounder Yuvraj Singh, was named "man-tournament" for this World Cup 2011. With him, the
the most celebrated players were batsmanSachin Tendulkar and captain and wicket-keeper Mahi Dhoni. Mahi is considered by fans and by his teammates as the best captain of the "men in blue", as the Indian national cricket team are known

Polythene Pollution

2011-01-13T22:34:00.000-08:00

Every year, around 500 billion plastic bags are used worldwide. 500,000,000,000. Five hundred followed by nine zeros. That's a lot of bags. So many that over one million bags are being used every minute and they're damaging our environment.

Big numbers can be daunting so let's put it another way. Every man, woman and child on our planet uses 83 plastic bags every year. That's one bag per person every four and half days. Of those 500 billion bags, 100 billion are consumed in the United States alone.

Causes of Plastic Pollution

Plastics are used because they are easy and cheap to make and they can last a long time. Unfortunately these same useful qualities can make plastic a huge pollution problem. Because the plastic is cheap it gets discarded easily and its persistence in the environment can do great harm. Urbanisation has added to the plastic pollution in concentrated form in cities. Plastic thrown on land can enter into drainage lines and chokes them resulting into floods in local areas in cities as experienced in Mumbai, India in 1998. It was claimed in one of the programmes on TV Channel that eating plastic bags results in death of 100 cattles per day in U.P. in India. In stomach of one dead cow, as much as 35 kg of plastic was found. Because plastic does not decompose, and requires high energy ultra-violet light to break down, the amount of plastic waste in our oceans is steadily increasing. More than 90% of the articles found on the sea beaches contained plastic. The plastic rubbish found on beaches near urban areas tends to originate from use on land, such as packaging material used to wrap around other goods

Control Measures

• REDUCE

The weight of a plastic bag is about one-tenth the weight of a paper bag. Besides using less material, plastic bags produce less than half the greenhouse gas emissions (a lower carbon footprint), require 70 per cent less energy to manufacture and generate 80 per cent less waste than paper alternatives. Proper bagging can help reduce waste even further.

• REUSE

Plastic bags are arguably one of the most reused products in our society. Over 90 per cent of families reuse plastic bags around their homes for a wide range of purposes, such as bringing lunch to work, lining garbage bins, disposing of diapers and for other sundry usages. The high percentage of reuse enables shoppers to avoid the added environmental impacts associated with using a new bag.

• RECYCLE

Plastic bags are fully recyclable. They are a valuable resource that can be reused and recycled several times over. These are used in building & construction, roads and new plastic bags. (Wal-Mart reportedly recycles about 120 million pounds or approx. 54 KT per year). While recycling helps in protecting the environment and in recovery of energy, it also provides immense employment generation opportunities.

Kidney stones

2011-01-13T22:02:00.000-08:00

What is Kidney stones?

Kidney stones are one of the most painful disorders that affect humans. Kidney stones are solid masses of mineral salt deposits that are normally filtered through the kidney and emptied via urine. Urine has a natural substance, which dissolves these minerals, thereby preventing them into becoming solids or calculi. Sometimes due to dehydration, these salts don’t get dissolved and crystallization takes place. It grows large enough to obstruct the renal ducts or stuck in the uterus, causing sharp and severe pain in the urinary tract. Untreated, kidney stones can cause renal failure.

Common Causes of Kidney stones

Urinary tract infection (UTI)
Overdoses of Vitamin D
Mineral imbalance
Kidney disease
Dehydration
Gout
Diet

Home Remedies for Kidney stones

Tip 1:

Boil two figs in a cup of water. Drink this first thing in the morning for one month.

Tip 2:

Mix 1 tspn of Holy basil leaves juice with 1 tspn of honey. Have this every morning for 5-6 months.
Eat 2-3 Apples a day.

Tip 3:

Watermelon, either eaten as a fruit or had a juice is very good.

Tip 4:

1 cup of juice made with radish leaves taken 2 times a day.

Tip 5:

First thing in the morning, drink 1 glass of fresh Tomato juice. Add a pinch of salt and pepper to this.

Microsoft® Office 2010

2010-01-09T05:15:00.000-08:00

Microsoft® Office 2010 offers rich and powerful new ways to deliver your best work at the office, home, or school. Grab your audience’s attention and inspire them with your ideas visually. Create results with people at the same time and stay connected to your files across the town or around the world.¹ With Office 2010, you’re in control of getting things done and delivering amazing results according to your schedule.

Top 10 Benefits of Office 2010

1 Express your ideas more visually

Office 2010 opens up a world of design options to help you give life to your ideas. The new and improved picture formatting tools such as color saturation and artistic effects let you transform your document visuals into a work of art. Combined with a wide range of new pre-built Office themes and SmartArt® graphic layouts, Office 2010 gives you more ways to make your ideas stick.

2 Accomplish more when working together

Brainstorm ideas, provide better version control, and meet deadlines faster when you work in groups. The co-authoring experience for Microsoft® Word 2010, Microsoft PowerPoint 2010, Microsoft® Excel Web App and Microsoft OneNote shared notebooks let you work on a file with several people at once - even from different locations.2

3 Enjoy the familiar Office experience from more locations and more devices

With Office 2010, you can get things done more easily, from more locations and more devices. Using a smartphone or virtually any computer with an Internet connection, you can work when and where you want to work.3

Microsoft Office Web Apps
Extend your Office 2010 experience to the Web. Store your Word, Excel, PowerPoint, and OneNote files online and then access, view, edit, and share content through the web.

Microsoft Office Mobile 2010
Stay current and respond quickly using enhanced mobile versions of Office 2010 applications, specifically suited to your Windows Mobile-based smartphone.

4 Create powerful data insights and visuals

Track and highlight important trends with new data analysis and visualization features in Excel 2010. The new Sparklines feature delivers a clear and compact visual representation of your data with small charts within worksheet cells. Filter and segment your PivotTable data in multiple layers using Slicers to spend more time analyzing and less time formatting.

5 Deliver compelling presentations

Captivate your audience with personalized videos in your presentation. Insert and customize videos directly in PowerPoint 2010—trim, add fades and effects, or bookmark key points in the video to call attention to selected scenes. Videos you insert are now embedded by default, relieving you from managing and sending additional video files.

6 Manage large volumes of e-mail with ease

Compress your long e-mail threads into a few conversations that can be categorized, filed, ignored, or cleaned up. The new Quick Steps feature let you perform multi-command tasks, such as reply and delete an e-mail in a single click, saving you time and in-box space.

7 Store and track all your ideas and notes in one place

Get the ultimate digital notebook for tracking, organizing, and sharing your text, picture, video and audio notes with OneNote 2010. New features such as version tracking, automatic highlighting, and Linked Notes give you more control over your notes so you’re always on top of where your ideas came from and the latest changes when working in teams.4

8 Get your message out instantly

Broadcast your PowerPoint presentation to a remote audience, whether or not they have PowerPoint installed.5 The new Broadcast Slide Show feature allows you to share your presentation through a web browser quickly without additional set up.

9 Get things done faster and easier

Microsoft Office Backstage™ view replaces the traditional File menu to give you a centralized space for all of your file management tasks, such as the ability to save, share, print, and publish. The enhanced Ribbon across Office 2010 applications lets you access commands quickly and customize tabs to personalize the experience to your work style.

10 Access work across devices and platforms

Enjoy the freedom of using Office 2010 from more locations on more devices. When you use Microsoft® Office 2010, you’re getting the familiar and intuitive Office experience across PCs, Smartphones, and Web browsers on the go.

Download Microsoft® Office 2010

Free Softwares

2010-01-01T22:00:00.000-08:00

Office

OpenOffice - office suite
PC Suite 602 - office suite
AbiWord - text editor
Atlantis Nova - text editor
Microsoft PowerPoint Viewer - power point files viewer
Adobe Reader - pdf reader
Foxit PDF Reader - pdf reader
PDFCreator - create pdf documents
Doc Convertor - document convertor
Convert - unit convertor
Converber - unit convertor
Sunbird - calendar/organizer
EssentialPIM Free - calendar/organizer
PhraseExpress - speed up your writing
ATnotes - create notes on the desktop

Archive managers

7-Zip - compression program
IZArc - compression program
TugZIP - compression program
CabPack - compression program
Universal Extractor - extract files from any type of archive

Internet

Firefox - web browser
Internet Explorer- web browser
Maxthon - web browser
Opera - web browser
Avant Browser - web browser
Thunderbird - email client
PopTray - check for emails
Free Download Manager - download manager
FlashGet - download manager
WellGet - download manager
Download Master - download manager
WGET - commandline download manager
HTTrack - offline browser
WebReaper - offline browser
Yeah Reader - RSS reader
GreatNews - RSS reader
RSSOwl - RSS reader

P2P

ÂµTorrent - torrent client
Azureus - torrent client
BitComet - torrent client
ABC - torrent client
BitTornado - torrent client
eMule - p2p client
SoulSeek - p2p client
Shareaza - p2p client
DC++ - Direct Connect network client
PeerGuardian - IP blocker

Chat

Miranda - chat client
MSN Messenger - chat client
Yahoo Messenger - chat client
QIP - chat client
Gaim - chat client
JAJC - chat client
HydraIRC - IRC client
Talkative IRC - IRC client
IceChat - IRC client
Skype - VOIP client
Google Talk - VOIP client
VoipStunt - VOIP client
Gizmo - VOIP client
Wengo - VOIP client

Security

AVG Free - antivirus
Avast Home Free - antivirus
AntiVir PersonalEdition - antivirus
BitDefender Free - antivirus
ClamWin - antivirus
CyberDifender - Internet Security Suite
Ad-aware - anti-spyware
Spybot: Search & Destroy - anti-spyware
Windows Defender - anti-spyware
SpywareBlaster - anti-spyware
Spyware Terminator - anti-spyware
Tootkit Reveaker - rootkit detection utility
Winpooch - system protection
HiJack Free - system protection
HighJackThis - hijackers detector and remover
Kerio Personal Firewall - firewall
Sygate Personal Firewall - firewall
ZoneAlarm - firewall
AxCrypt - file encryption
Simple File Shredder - securely delete files
PuTTy - SSH client
KeePass - password manager
LockNote - password manager
nPassword - password manager
Microsoft Baseline Security Analyzer - identify security misconfigurations

Network

Hamachi - VPN client
RealVNC - remote control
UltraVNC - remote control
Ethereal - local area network administration
The Dude - network administration
Wireshark - network administration
Angry IP Scanner - IP scanner
IP-Tools - IP scanner
Free Port Scanner - IP scanner
NetMeter - network bandwidth monitoring

Servers

FileZilla - FTP client
FileZilla Server - FTP server
EFTP - FTP client/server
XAMPP - integrated server package of Apache, mySQL, PHP and Perl
WAMP - Apache, PHP5 and MySQL server

Audio

Foobar2000 - audio player
WinAmp - audio player
1by1 - audio player
JetAudio - audio player
XMPlay - audio player
Xion - audio player
Apollo - audio player
MediaMonkey - music organizer
The GodFather - music organizer
dBpowerAMP - audio converter
Audacity - audio converter
WavePad - audio converter
Kristal Audio Engine - audio editor
Exact Audio Copy - CD ripper
Audiograbber - CD ripper
CDex - CD ripper
Mp3 Tag Tools - tag editor
Mp3tag - tag editor
Tagginâ€™ MP3 - tag editor
Monkeyâ€™s Audio - APE compressor/decompre ssor
mpTrim - mp3 editor
WavTrim - wave editor
EncSpot Basic - analyse mp3 files

Video

Windows Media Player - audio/video player
VLC - video player
Media Player Classic - video player
MV2Player - video player
CrystalPlayer 1.95 - video player
Zoom Player - video player
GOM Player - video player
viPlay - video player
DSPlayer - video player
VirtualDub - video editor
CamStudio - video screen recording
AviSplit - Avi splitter
Video mp3 Extractor - rip audio from video files
Free iPod Converter - convert all popular video formats to iPod video
MediaPortal - turning your PCinto a Media Center
The FilmMachine

Image

Gimp - image editor
PhotoFiltre - image editor
Paint.net - image editor
ArtRage - image editor
Artweaver - image editor
IrfanView - image viewer
Picasa - image viewer
XnView - image viewer
FastStone Image Viewer - image viewer
FuturixImager - image viewer
Easy Thumbnails - create thumbnails from images
JoJoThumb - create thumbnails from images
iWebAlbum - create web photo albums
JAlbum - create web photo albums
3D Box Shot Maker - design quality box shot
FastStone Capture - screen capture
WinSnap - screen capture

Blender3D - 3D renderer
3Delight Free - 3D renderer
SketchUp - 3D modeling
Maya Learning Edition - 3D modeling

Developers

AutoIt - task automation
SciTE4AutoIt3 - text editor for AutoIt
AutoHotkey - task automation
PHP Designer - PHP editor
Notepad++ - text editor
ConTEXT Editor - text editor
PSPad - text editor
FoxEditor - text editor
Crimson Editor - source code editor
Elfima Notepad - text editor
Notepad2 - text editor
Nvu - HTML editor
Alleycode - HTML editor
BlockNote - web page editor
Weaverslave - web page editor

CD/DVD

DeepBurner - CD/DVD burner
CDBurner XP Pro - CD/DVD burner
BurnAtOnce - CD/DVD burner
Express Burn - CD/DVD burner
Zilla CD-DVD Ripâ€™nâ€™Burn - CD/DVD burner
ImgBurn - ISO, BIN burner
Daemon tools - virtual CD/DVD
DVD Decrypter - DVD ripper
DVD Shrink - DVD ripper
Nero CD-DVD Speed - CD/DVD info and quality test

Codecs

GSpot - codec information
AC3Filter - audio codec
Xvid - video codec
QuickTime Alternative - video codec
Real Alternative - video codec
K-Lite Codec Pack - all codecs

System Ulilities

CCleaner - system cleaner
xp-AntiSpy - OS setup
jv16 Powertools - system utilities
XP SysPad - system monitoring utility
Whatâ€™s Running - process guard
Registrar Lite - registry editor
WinIPConfig - replacement for â€œipconfig.exeâ€ and â€œroute.exeâ€
Unlocker - file eraser
Eraser - secure file eraser
Undelete Plus - file recovery
freeCommander - file manager
ExplorerXP - file manager
Duplicate File Finder - find all duplicate files
Ant Renamer - file renaming
ReNamer - file renaming
Icons From File - icos extractor
Chaos MD5 - MD5 generator
HashTab - MD5, SHA1 and CRC-32 file hashes
Rainlendar Lite - desktop calendar
Weather Watcher - weather firecast
Subtitle Workshop - subtitles editor
Ant Movie Catalog - movie organizer
Disclib - CD organizer
Dexpot - virtual desktops
DriveImage XML - create partition images
MozBackup - backup and restore bookmarks, etc.
SyncBack - system backup
Atomic Cock Sync - syncronize your clock
Citrus Alarm Clock - alarm clock
TaskSwitchXP - Alt-Tab replacement
Launchy - application launcher
allSnap - make all windows snap
Sysinternals Tools - various system tools
StrokeIt - mouse gestures
Net Profiles - create profiles of your network settings
ResourceHacker - view, modify, rename, add, delete
Java Runtime Environment - java for Windows

UI Enhancements

RocketDock - application launcher
AveDesk - desktop enhancer
IconPhile - customize windowsâ€™s system icons
CursorXP Free - change mouse cursors
MacSound - volume control
LClock - Windows Longhorn clock
Yâ€™z Dock - application launcher
Yâ€™z Shadow - shadow effect to the windows
Yâ€™z Toolbar - change the toolbar icons in Explorer and Internet Explorer
Taskbar Shuffle - rearrange the programs on the taskbar by dragging
Visual Task Tips - thumbnail preview image for each task in the taskbar
Badges - put badges on any folder or file
Folderico - change icons of the folders
Folder Marker - mark your folders
Folder2MyPC - add favourite locations to My Computer
Microsoft TweakUI - system settings
BricoPacks - shell packs
ShellPacks - shell packs
Tango Shell Patcher - shell patcher
XPize - GUI enhancer
Vista Transformation Pack - complete visual style
Vista Sound Scheme - Windows Vista sound scheme
Royale Theme - visual style

Hardware monitoring/Benchmar king

CPU-Z - cpu information
CrystalCPUID - cpu information
Central Brain Identifier - cpu information
Everest - system information
SiSoft Sandra - system information
SpeedFan - hardware monitor
Memtest86 - memory test
PowerMax - HDD test
3Dmark 06 - 3D game performance benchmark
Aquamark - performance benchmark
rthdribl - 3D benchmark
Fraps - 3D benchmark, fps viewer and screen recorder
Prime 95 - cpu benchmarking
SuperPI - cpu benchmarking
CPU Rightmark - cpu overclock
Core Temp - cpu temperature
ATiTool - video overclock
ATI Tray Tools - Radeon tweaker
aTuner - GeForce and Radeontweaker
RivaTuner - video overclock
Nokia Monitor Test - monitor adjustmets
UDPixel - fix dead pixels

Games

123 Free Solitaire - solitaire games collection
Arcade Pack - classic arcade games
Live For Speed - online racing simulator
Enigma - puzzle game
Freeciv - multiplayer strategy game
Tux Racer - race down steep, snow-covered mountains

Education

SpeQ Mathematics - mathematics program
Dia - diagram creation program
Google Earth - explore the world
NASA World Wind - 3D virtual globe
Celestia - explore the space
Stellarium - planetarium

Miscellaneous

nLite - Build your own custom Windows disk.
VirtualPC - create virtual machines
grabMotion - webcam capture
iDailyDiary - simple page-for-a-day diary
Pivot Stickfigure Animator - create stick-figure animations
Wink - create presentations
Scribus - professional page layout
FreeMind - midn mapping software
Windows Live Writer - WYSIWYG blog authoring

Improve your Windows 7

2010-01-01T21:58:00.000-08:00

Microsoft Windows 7 Your Way:

Speed Up and Customize Window

Want to make Windows 7 run faster, smarter, easier, better? Want to personalize Windows to look and act the way you want it to? Want to get more efficient and ditch all those Windows hassles? You don’t need a Ph.D in computer science or expensive upgrades. All you need is this book!

Michael Miller makes it easy to tweak Windows so it works just like you want it to–and runs smooth as silk for years to come. No extreme hacking required: These are simple, step-by-step techniques anyone can perform in minutes–even beginners!

- Customize Windows 7’s desktop for the way you work

- Strip out bloated, worthless software that slows your PC down

- Get your network running faster and more reliably

- Surf the Web more quickly and safely

- Improve performance and battery life on notebooks and netbooks

- Get more security with fewer annoyances

- Discover great free and cheap alternatives to Microsoft’s built-in software

- Fix Windows 7’s most aggravating problems

- And much more...

Michael Miller has written more than 100 non-fiction how-to books over the past 20 years, including Que’s Absolute Beginner’s Guide to Computer Basics, Speed It Up! A Non-Technical Guide for Speeding Up Slow Computers, and How Microsoft Windows Vista Works. His books have sold more than 1 million copies worldwide. He has earned a reputation for clearly explaining technical topics to non-technical readers and for offering useful real-world advice about complex topics.

Download Link

Lessons In Electric Circuits: DIGITAL BOOK

2009-08-08T00:52:00.000-07:00

Chapter 1: NUMERATION SYSTEMS [ contents: Numbers and symbols ~ Systems of numeration ~ Decimal versus binary numeration ~ Octal and hexadecimal numeration ~ Octal and hexadecimal to decimal conversion ~ Conversion from decimal numeration ]
Chapter 2: BINARY ARITHMETIC [ contents: Numbers versus numeration ~ Binary addition ~ Negative binary numbers ~ Subtraction ~ Overflow ~ Bit groupings ]
Chapter 3: LOGIC GATES [ contents: Digital signals and gates ~ The NOT gate ~ The “buffer” gate ~ Multiple-input gates ~ TTL NAND and AND gates ~ TTL NOR and OR gates ~ CMOS gate circuitry ~ Special-output gates ~ Gate universality ~ Logic signal voltage levels ~ DIP gate packaging ~ Contributors ]
Chapter 4: SWITCHES [ contents: Switch types ~ Switch contact design ~ Contact “normal” state and make/break sequence ~ Contact “bounce” ]
Chapter 5: ELECTROMECHANICAL RELAYS [ contents: Relay construction ~ Contactors ~ Time-delay relays ~ Protective relays ~ Solid-state relays ]
Chapter 6: LADDER LOGIC [ contents: “Ladder” diagrams ~ Digital logic functions ~ Permissive and interlock circuits ~ Motor control circuits ~ Fail-safe design ~ Programmable logic controllers ~ Contributors ]
Chapter 7: BOOLEAN ALGEBRA [ contents: Introduction ~ Boolean arithmetic ~ Boolean algebraic identities ~ Boolean algebraic properties ~ Boolean rules for simplification ~ Circuit simplification examples ~ The Exclusive-OR function ~ DeMorgan’s Theorems ~ Converting truth tables into Boolean expressions ]
Chapter 8: KARNAUGH MAPPING [ contents: Introduction ~ Venn diagrams and sets ~ Boolean Relationships on Venn Diagrams ~ Making a Venn diagram look like a Karnaugh map ~ Karnaugh maps, truth tables, and Boolean expressions ~ Logic simplification with Karnaugh maps ~ Larger 4-variable Karnaugh maps ~ Minterm vs maxterm solution ~ (sum) and (product) notation ~ Don’t care cells in the Karnaugh map ~ Larger 5 & 6-variable Karnaugh maps ]
Chapter 9: COMBINATIONAL LOGIC FUNCTIONS [ contents: Introduction ~ A Half-Adder ~ A Full-Adder ~ Decoder ~ Encoder ~ Demultiplexers ~ Multiplexers ~ Using multiple combinational circuits ]
Chapter 10: MULTIVIBRATORS [ contents: Digital logic with feedback ~ The S-R latch ~ The gated S-R latch ~ The D latch ~ Edge-triggered latches: Flip-Flops ~ The J-K flip-flop ~ Asynchronous flip-flop inputs ~ Monostable multivibrators ]
Chapter 11: COUNTERS [ contents: Binary count sequence ~ Asynchronous counters ~ Synchronous counters ~ Counter modulus ]
Chapter 12: SHIFT REGISTERS [ contents: Introduction ~ Serial-in/serial-out shift register ~ Parallel-in, serial-out shift register ~ Serial-in, parallel-out shift register ~ Parallel-in, parallel-out, universal shift register ~ Ring counters ~ references ]
Chapter 13: DIGITAL-ANALOG CONVERSION [ contents: Introduction ~ The R/2nR DAC ~ The R/2R DAC ~ Flash ADC ~ Digital ramp ADC ~ Successive approximation ADC ~ Tracking ADC ~ Slope (integrating) ADC ~ Delta-Sigma () ADC ~ Practical considerations of ADC circuits ]
Chapter 14: DIGITAL COMMUNICATION [ contents: Introduction ~ Networks and busses ~ Data flow ~ Electrical signal types ~ Optical data communication ~ Network topology ~ Network protocols ~ Practical considerations ]
Chapter 15: DIGITAL STORAGE (MEMORY) [ contents: Why digital? ~ Digital memory terms and concepts ~ Modern nonmechanical memory ~ Historical, nonmechanical memory technologies ~ Read-only memory ~ Memory with moving parts: “Drives” ]
Chapter 16: PRINCIPLES OF DIGITAL COMPUTING [ contents: A binary adder ~ Look-up tables ~ Finite-state machines ~ Microprocessors ~ Microprocessor programming ]
Chapter 17: CONTRIBUTOR LIST [ contents: How to contribute to this book ~ Credits
Download

Elsevier - Starting Electronics - 3rd Edition

2009-08-08T00:40:00.000-07:00

Paperback, 288 pages,
Publication date: SEP-2004
ISBN-13: 978-0-7506-6386-1
ISBN-10: 0-7506-6386-3
Imprint: NEWNES

Description:
Starting Electronics is unrivalled as a highly practical introduction for hobbyists, students and technicians. Keith Brindley introduces readers to the functions of the main component types, their uses, and the basic principles of building and designing electronic circuits. Breadboard layouts make this very much a ready-to-run book for the experimenter; and the use of multimeter, but not oscilloscopes, puts this practical exploration of electronics within reach of every home enthusiast's pocket. The third edition has kept the simplicity and clarity of the original. New material includes sections on transducers and more practical examples of digital ICs.

Download : http://edudirectory2.googlepages.com/Elsevier-StartingElectronics-3rdEdit.rar

Acne

2009-07-26T08:15:00.000-07:00

A general information all about the acne scars, effects of acne scars and its proper medication.

Macules and Scars:
Before I jump into the topic of scars, I need to clarify the difference between Macules and Scars. Macules may look like scars, but they are not scars in the sense that a permanent change has occurred. Macules are essentially the final stage of most inflamed acne lesions. They are normally flat, reddish spots that can remain for up to 8 months. But the difference between a Macule and a scar is that a Macule will end up disappearing completely whereas a scar will remain for years or indefinitely.

As for scars, this can also vary from person to person. With some individuals, scars may remain for a lifetime without change but with others, their skin will undergo a form of remodeling that will eventually diminish the scar.

Another factor that needs to be evaluated is the human element of scarring. People simply have different feelings about acne scars. Those who are distressed about their acne scars are much more likely to actively seek out treatment to moderate or remove the scar than those who are more indifferent about the scars.

Cause of Scars:
Let us first gain a better understanding of acne scars by first determining the cause of scars. A scar is a mark left in the skin by the healing of a wound or surgical incision in which the normal functional tissue (skin) is replaced by connective tissue (scar). In the case of acne, the lesion is caused by the body's inflammatory response to sebum, bacteria and dead cells that are trapped in the plugged sebaceous follicle.

When your skin tissue has suffered a lesion of some sorts, your body will attempt to heal the injured site. It does so by increasing the white blood cells in the area along with an array of inflammatory molecules whose function is to repair the damaged tissue and fight infection. In the end, the repair job can be messy, and the site of the lesion is now filled with fibrous scar tissue or eroded tissue. As for the inflammatory molecules and white blood cells, they can remain at the acne lesion for days and even weeks.

Take note of the fact that not everyone functions in the same way, and this holds true with our skin as well. Some people are simply more prone to scarring than others.

Treatment for scars:
Bear in mind that treating acne and treating acne scars are two completely different things. Treating your acne has nothing to do with treating an acne scar. Acne scars can indeed be treated, but it is important that an acne sufferer bring their acne condition under control first if they still suffer from moderate to severe acne.

Once your acne subsides, make an appointment with a dermatologist and discuss the methods (if applicable) of scar treatment(s) he/she recommend you undergo to treat your scars. Keep in mind that there are many methods with which you may treat your scars. These methods vary according to your scar type, size and location, type of skin, and of course, money $$$. All this should be discussed in great detail with your dermatologist.

Before undergoing scar treatment, ask yourself the following questions before having your dermatologist undergo the decided procedure(s).: Are you willing to wait and see if the scars will subside on their own with time? Do your acne scars affect you emotionally and socially? Is your scarring substantial enough to warrant scar treatment? Can you afford the treatment or what treatment options can you afford?

Keep in mind, the objective of scar treatment is not to necessarily rid you of all indications of scars by completely restoring your skin. It very much depends on the severity of your scars, your skin type, your skins ability to regenerate, etc. Significant improvements can definitely be achieved, but complete restoration is often impossible.

About the Author: Kerwin Chang writes for http://www.acnestuff.net where you can find out more about acne and other skin care topics

Bioplastics

2009-07-26T07:59:00.000-07:00

Bioplastics are a form of plastics derived from renewable biomass sources, such as vegetable oil, corn starch, pea starch , microbiota , rather than traditional plastics which are derived from petroleum. They are used either as a direct replacement for traditional plastics or as blends with traditional plastics. There is no international agreement on how much bio-derived content is required to use the term bioplastic.

Bioplastics and biodegradation

The terminology used in the bioplastics sector is sometimes misleading. Most in the industry use the term bioplastic to mean a plastic produced from a biological source. One of the oldest plastics, cellulose film, is made from wood cellulose. All bio- and petroleum-based plastics are technically biodegradable, meaning they can be degraded by microbes under suitable conditions. However many degrade at such slow rates as to be considered non-biodegradable. Some petrochemical-based plastics are considered biodegradable, and may be used as an additive to improve the performance of many commercial bioplastics. Non-biodegradable bioplastics are referred to as durable. The degree of biodegradation varies with temperature, polymer stability, and available oxygen content. Consequently, most bioplastics will only degrade in the tightly controlled conditions of commercial composting units. An internationally agreed standard, EN13432, defines how quickly and to what extent a plastic must be degraded under commercial composting conditions for it to be called biodegradable. This is published by the International Organisation for Standardization ISO and is recognised in many countries, including all of Europe, Japan and the US. However, it is designed only for the aggressive conditions of commercial composting units. There is no standard applicable to home composting conditions.

The term "biodegradable plastic" is often also used by producers of specially modified petrochemical-based plastics which appear to biodegrade. Traditional plastics such as polyethylene are degraded by ultra-violet (UV) light and oxygen. To prevent this process manufacturers add stabilising chemicals. However with the addition of a degradation initiator to the plastic, it is possible to achieve a controlled UV/oxidation disintegration process. This type of plastic may be referred to as degradable plastic or oxy-degradable plastic or photodegradable plastic because the process is not initiated by microbial action. While some degradable plastics manufacturers argue that degraded plastic residue will be attacked by microbes, these degradable materials do not meet the requirements of the EN13432 commercial composting standard.

Environmental impacts

The production and use of bioplastics is generally regarded as a more sustainable activity when compared with plastic production from petroleum, because it relies less on fossil fuel as a carbon source and also introduces less, net-new greenhouse emissions if it biodegrades. However, manufacturing of bioplastic materials is often still reliant upon petroleum as an energy and materials source. This comes in the form of energy required to power farm machinery and irrigate growing crops, to produce fertilisers and pesticides, to transport crops and crop products to processing plants, to process raw materials, and ultimately to produce the bioplastic.
Italian bioplastic manufacturer Novamont states in its own environmental audit producing one kilogram of its starch-based product uses 500g of petroleum and consumes almost 80% of the energy required to produce a traditional polyethylene polymer. Environmental data from NatureWorks, the only commercial manufacturer of PLA (polylactic acid) bioplastic, says that making its plastic material delivers a fossil fuel saving of between 25 and 68 per cent compared with polyethylene, in part due to its purchasing of renewable energy certificates for its manufacturing plant.

A detailed study the process of manufacturing a number of common packaging items in several traditional plastics and polylactic acid carried out by US-group published by the Athena Institute the bioplastic to be less environmentally damaging for some products, but more environmentally damaging for others.
While production of most bioplastics results in reduced carbon dioxide emissions compared to traditional alternatives, there are some real concerns that the creation of a global bioeconomy could contribute to an accelerated rate of deforestation if not managed effectively. There are associated concerns over the impact on water supply and soil erosion.

Cost

With the exception of cellulose, most bioplastic technology is relatively new and is currently not as cost competitive with petroleum-based plastics. Many bioplastics are reliant on fossil fuel-derived energy for their manufacturing, reducing the cost advantage over petroleum-based plastic.

Performance and usage

Many bioplastics lack the performance and ease of processing of traditional materials, albeit materials such as Bioplast from Stanelco closed this performance gap. Polylactic acid plastic is being used by a handful of small companies for water bottles. But shelf life is limited because the plastic is permeable to water - the bottles lose their contents and slowly deform.[citation needed] However, bioplastics are seeing some use in Europe, where they account for 60% of the biodegradable materials market. The most common end use market is for packaging materials. Japan has also been a pioneer in bioplastics, incorporating them into electronics and automobiles.

Recycling

There are also fears that bioplastics will damage existing recycling projects. Packaging such as HDPE milk bottles and PET water and soft drinks bottles is easily identified and hence setting up a recycling infrastructure has been quite successful in many parts of the world. Polylactic acid and PET do not mix - as bottles made from polylactic acid cannot be distinguished from PET bottles by the consumer there is a risk that recycled PET could be rendered unusable. This could be overcome by ensuring distinctive bottle types or by investing in suitable sorting technology. However, the first route is unreliable and the second costly.

Genetically modified bioplastics

Genetic modification (GM) is also a challenge for the bioplastics industry. None of the currently available bioplastics - which can be considered first generation products - require the use of GM crops. However, it is not possible to ensure corn used to make bioplastic in North America is GM-free.

European consumers are hostile to any products that are linked to the GM industry. As a result, some UK retailers such as Sainsbury's not use bioplastic manufactured in the US, such as Natureworks polylactic acid. There is currently no commercial European source of polylactic acid bioplastic.

There is also concern that the route from corn to bioplastics is not the most efficient. Looking further ahead, some of the second generation bioplastics manufacturing technologies under development employ the "plant factory" model, using genetically modified crops or genetically modified bacteria to optimise efficiency. However, a change in consumer perception of GM technology in Europe will be required for these to be widely accepted.

Market size

Because of the fragmentation in the market it is difficult to estimate the total market size for bioplastics, but estimates by SRI global consumption in 2006 at around 85,000 tonnes. In contrast, global consumption of all flexible packaging is estimated at around 12.3 million tonnes.
COPA (Committee of Agricultural Organisation in the European Union) and COGEGA (General Committee for the Agricultural Cooperation in the European Union) have made an assessment of the potential of bioplastics in different sectors of the European economy:
Catering products: 450,000 tonnes per year
Organic waste bags: 100,000 tonnes per year
Biodegradable mulch foils: 130,000 tonnes per year
Biodegradable foils for diapers 80,000 tonnes per year
Diapers, 100% biodegradable: 240,000 tonnes per year
Foil packaging: 400,000 tonnes per year
Vegetable packaging: 400,000 tonnes per year
Tyre components: 200,000 tonnes per year
Total 2,000,000 tonnes per year

Certification

Biodegradability - EN 13432, ASTM D6400

The EN 13432 industrial standard is arguably the most international in scope and compliance with this standard is required to claim that a product is compostable in the European marketplace. In summary, it requires biodegradation of 90% of the materials in a commercial composting unit within 90 days. The ASTM 6400 standard is the regulatory framework for the United States and sets a less stringent threshold of 60% biodegradation within 180 days, again within commercial composting conditions.

The "compostable" marking found on many items of packaging indicates that the package complies with either of the two standards mentined above. However, the marking is not owned by either regulatory body but by third party trade associations representing companies making or selling biodegradable plastics. In Europe, this is European Bioplastics, in the U.S. it is the Biodegradable Products Institute.

Many starch based plastics, PLA based plastics and certain aliphatic-aromatic co-polyester compounds such as succinates and adipates, have obtained these certificates. Additivated plastics sold as fotodegradable or oxobiodegradable do not comply with these standards in their current form.

Biobased - ASTM D6866

The ASTM D6866 method has been developed to certify the biologically derived content of bioplastics. There is an important difference between biodegradability and biobased content. A bioplastic such as high density polyethylene (HDPE) can be 100% biobased (i.e. contain 100% renewable carbon), yet be non-biodegradable. These bioplastics such HDPE play nonetheless an important role in greenhouse gas abatement, particularly when they are combusted for energy production. The biobased component of these bioplastics is considered carbon-neutral since their origin is from biomass.

Applications

Because of their biological biodegradability, the use of bioplastics is especially popular for disposable items, such as packaging and catering items (crockery, cutlery, pots, bowls, straws). The use of bioplastics for shopping bags is already very common[citation needed]. After their initial use they can be reused as bags for organic waste and then be composted. Trays and containers for fruit, vegetables, eggs and meat, bottles for soft drinks and dairy products and blister foils for fruit and vegetables are also already widely manufactured from bioplastics.
Non-disposable applications include mobile phone casings (NEC), carpet fibres (Dupont Sorona), and car interiors (Mazda). The French company, Arkema, produces a grade of bioplastic called Rilsan, which is being used in fuel line and plastic pipe applications. In these areas, the goal is obviously not biodegradability, but to create items from sustainable resources.
Plastic types

Starch based plastics

Constituting about 50 percent of the bioplastics market, thermoplastic starch, such as Plastarch Material, currently represents the most important and widely used bioplastic. Pure starch possesses the characteristic of being able to absorb humidity and is thus being used for the production of drug capsules in the pharmaceutical sector. Flexibiliser and plasticiser such as sorbitol and glycerine are added so that starch can also be processed thermo-plastically. By varying the amounts of these additives, the characteristic of the material can be tailored to specific needs (also called "thermo-plastical starch").

Polylactide acid (PLA) plastics

Polylactide acid (PLA) is a transparent plastic produced from cane sugar or corn starch. It not only resembles conventional petrochemical mass plastics (like PE or PP) in its characteristics, but it can also be processed easily on standard equipment that already exists for the production of conventional plastics. PLA and PLA-Blends (such as the CompostablesTM by Cereplast,Inc. ) generally come in the form of granulates with various properties and are used in the plastic processing industry for the production of foil, moulds, tins, cups, bottles and other packaging.

Poly-3-hydroxybutyrate (PHB)

The biopolymer poly-3-hydroxybutyrate (PHB) is a polyester produced produced by certain bacteria processing glucose or starch. Its characteristics are similar to those of the petrochemical-produced plastic polypropylene. The South American sugar industry, for example, has decided to expand PHB production to an industrial scale. PHB is distinguished primarily by its physical characteristics. It produces transparent film at a melting point higher than 130 degrees Celsius, and is biodegradable without residue.

Polyamide 11 (PA 11)

PA 11 is a biopolymer derived from natural oil. It is also known under the tradename Rilsan B commercialized by Arkema. PA 11 belongs to the technical polymers family and is not biodegradable. Its properties are similar than PA 12 although emissions of greenhouse gases and consumption of non-renewable resources are reduced during its production. Its thermal resistance is also superior than PA 12. It is used in high performance applications as automotive fuel lines, pneumatic airbrake tubing, electrical anti-termite cable sheathing, oil & gas flexible pipes & control fluid umbilicals, sports shoes, electronic device components, catheters, etc.

Bio-derived polyethylene

The basic building block (monomer) of polyethylene is ethylene. This is just one small chemical step from ethanol, which can be produced by fermentation of agricultural feedstocks such as sugar cane or corn. Bio-derived polyethylene is chemically and physically identical to traditional polyethylene - it does not biodegrade but can be recycled. It can also considerably reduce greenhouse gas emissions. Brazilian chemicals group Braskem claims that using its route from sugar cane ethanol to produce one tonne of polyethylene captures (removes from the environment) 2.5 tonnes of carbon dioxide while the traditional petrochemical route results in emissions of close to 3.5 tonnes.

Braskem plans to introduce commercial quantities of its first bio-derived high density polyethylene, used in a packaging such as bottles and tubs, in 2010 and has developed a technology to produce bio-derived butene, required to make the linear low density polethylene types used in film production.

Developments

• In the early 1950s, Amylomaize (>50% starch content corn) was successfully bred and commercial bioplastics applications started to be explored.
• In 2004, NEC developed a flame retardant plastic, polylactic acid, without using toxic chemicals such as halogens and phosphorus compounds
• In 2005, Fujitsu became one of the first technology companies to make personal computer cases from bioplastics, which are featured in their FMV-BIBLO NB80K line.
• In 2007 Braskem of Brazil announced it had developed a route to manufacture high density polyethylene (HDPE) using ethylene derived from sugar cane.

Optical Fibre

2009-05-11T01:51:00.000-07:00

An optical fiber (or fibre) is a glass or plastic fiber that carries light along its length. Fiber optics is the overlap of applied science and engineering concerned with the design and application of optical fibers. Optical fibers are widely used in fiber-optic communications, which permits transmission over longer distances and at higher data rates (a.k.a "bandwidth"), than other forms of communications. Fibers are used instead of metal wires because signals travel along them with less loss, and they are immune to electromagnetic interference. Fibers are also used for illumination, and in bundles can be used to carry images, allowing viewing in tight spaces. Specially designed fibers are used for a variety of other applications, including as sensors and fiber lasers.

Light is kept in the "core" of the optical fiber by total internal reflection. This causes the fiber to act as a waveguide. Fibers which support many propagation paths or transverse modes are called multimode fibers (MMF). Fibers which support only a single mode are called singlemode fibers (SMF). Multimode fibers generally have a large-diameter core, and are used for short-distance communication links or for applications where high power must be transmitted. Singlemode fibers are used for most communication links longer than 200 meters.

Joining lengths of optical fiber is more complex than joining electrical wire or cable. The ends of the fibers must be carefully cleaved, and then spliced together either mechanically or by fusing them together with an electric arc. Special connectors are used to make removable connections.

History

Guiding of light by refraction, the principle that makes fiber optics possible, was first demonstrated by Daniel Colladon and Jacques Babinet in Paris in the 1840s, with Irish inventor John Tyndall offering public displays using water-fountains ten years later.^[1] Practical applications, such as close internal illumination during dentistry, appeared early in the twentieth century. Image transmission through tubes was demonstrated independently by the radio experimenter Clarence Hansell and the television pioneer John Logie Baird in the 1920s. The principle was first used for internal medical examinations by Heinrich Lamm in the following decade. In 1952, physicist Narinder Singh Kapany conducted experiments that led to the invention of optical fiber, based on Tyndall's earlier studies; modern optical fibers, where the glass fiber is coated with a transparent cladding to offer a more suitable refractive index, appeared later in the decade.^[1] Development then focused on fiber bundles for image transmission. The first fiber optic semi-flexible gastroscope was patented by Basil Hirschowitz, C. Wilbur Peters, and Lawrence E. Curtiss, researchers at the University of Michigan, in 1956. In the process of developing the gastroscope, Curtiss produced the first glass-clad fibers; previous optical fibers had relied on air or impractical oils and waxes as the low-index cladding material. A variety of other image transmission applications soon followed.

In 1965, Charles K. Kao and George A. Hockham of the British company Standard Telephones and Cables (STC) were the first to promote the idea that the attenuation in optical fibers could be reduced below 20 dB per kilometer, allowing fibers to be a practical medium for communication.^[2] They proposed that the attenuation in fibers available at the time was caused by impurities, which could be removed, rather than fundamental physical effects such as scattering. The crucial attenuation level of 20 dB was first achieved in 1970, by researchers Robert D. Maurer, Donald Keck, Peter C. Schultz, and Frank Zimar working for American glass maker Corning Glass Works, now Corning Incorporated They demonstrated a fiber with 17 dB optic attenuation per kilometer by doping silica glass with titanium. A few years later they produced a fiber with only 4 dB/km using germanium dioxide as the core dopant. Such low attenuations ushered in optical fiber telecommunications and enabled the Internet. In 1981, General Electric produced fused quartz ingots that could be drawn into fiber optic strands 25 miles long.

Attenuations in modern optical cables are far less than those in electrical copper cables, leading to long-haul fiber connections with repeater distances of 50–80 km. The erbium-doped fiber amplifier, which reduced the cost of long-distance fiber systems by reducing or even in many cases eliminating the need for optical-electrical-optical repeaters, was co-developed by teams led by David N. Payne of the University of Southampton, and Emmanuel Desurvire at Bell Laboratories in 1986. The more robust optical fiber commonly used today utilizes glass for both core and sheath and is therefore less prone to aging processes. It was invented by Gerhard Bernsee in 1973 of Schott Glass in Germany.

In 1991, the emerging field of photonic crystals led to the development of photonic crystal fiber ^[5] which guides light by means of diffraction from a periodic structure, rather than total internal reflection. The first photonic crystal fibers became commercially available in 2000. Photonic crystal fibers can be designed to carry higher power than conventional fiber, and their wavelength dependent properties can be manipulated to improve their performance in certain applications.

Applications

Optical fiber communication

Main article: Fiber-optic communication

Optical fiber can be used as a medium for telecommunication and networking because it is flexible and can be bundled as cables. It is especially advantageous for long-distance communications, because light propagates through the fiber with little attenuation compared to electrical cables. This allows long distances to be spanned with few repeaters. Additionally, the per channel light signals propagating in the fiber can be modulated at rates as high as 111 Gb/s. (In 2001 the limit was at 40 Gb/s. In today's DWDM systems the net data rate (data rate without overhead bytes) per fiber is the per channel data rate reduced by the FEC overhead multiplied by the number of channels (usually up to 80 channels in commercially available systems as of 2008). (Some communication companies are revealing that net data rates as fast as 1Tb/s are currently being developed.^[^{citation needed}^]), and each fiber can carry many independent channels, each by a different wavelength of light (wavelength-division multiplexing). Over short distances, such as networking within a building, fiber saves space in cable ducts because a single fiber can carry much more data than a single electrical cable. Fiber is also immune to electrical interference, which prevents cross-talk between signals in different cables and pickup of environmental noise. Also, wiretapping is more difficult compared to electrical connections, and there are concentric dual core fibers that are said to be tap-proof. Because they are non-electrical, fiber cables can bridge very high electrical potential differences and can be used in environments where explosive fumes are present, without danger of ignition.

Although fibers can be made out of transparent plastic, glass, or a combination of the two, the fibers used in long-distance telecommunications applications are always glass, because of the lower optical attenuation. Both multi-mode and single-mode fibers are used in communications, with multi-mode fiber used mostly for short distances (up to 500 m), and single-mode fiber used for longer distance links. Because of the tighter tolerances required to couple light into and between single-mode fibers (core diameter about 10 micrometers), single-mode transmitters, receivers, amplifiers and other components are generally more expensive than multi-mode components.

Fiber optic sensors

Main article: Fiber optic sensor

Fibers have many uses in remote sensing. In some applications, the sensor is itself an optical fiber. In other cases, fiber is used to connect a non-fiber optic sensor to a measurement system. Depending on the application, fiber may be used because of its small size, or the fact that no electrical power is needed at the remote location, or because many sensors can be multiplexed along the length of a fiber by using different wavelengths of light for each sensor, or by sensing the time delay as light passes along the fiber through each sensor. Time delay can be determined using a device such as an optical time-domain reflectometer.

Optical fibers can be used as sensors to measure strain, temperature, pressure and other quantities by modifying a fiber so that the quantity to be measured modulates the intensity, phase, polarization, wavelength or transit time of light in the fiber. Sensors that vary the intensity of light are the simplest, since only a simple source and detector are required. A particularly useful feature of such fiber optic sensors is that they can, if required, provide distributed sensing over distances of up to one meter.

Extrinsic fiber optic sensors use an optical fiber cable, normally a multimode one, to transmit modulated light from either a non-fiber optical sensor, or an electronic sensor connected to an optical transmitter. A major benefit of extrinsic sensors is their ability to reach places which are otherwise inaccessible. An example is the measurement of temperature inside aircraft jet engines by using a fiber to transmit radiation into a radiation pyrometer located outside the engine. Extrinsic sensors can also be used in the same way to measure the internal temperature of electrical transformers, where the extreme electromagnetic fields present make other measurement techniques impossible. Extrinsic sensors are used to measure vibration, rotation, displacement, velocity, acceleration, torque, and twisting.

Other uses of optical fibers

Fibers are widely used in illumination applications. They are used as light guides in medical and other applications where bright light needs to be shone on a target without a clear line-of-sight path. In some buildings, optical fibers are used to route sunlight from the roof to other parts of the building (see non-imaging optics). Optical fiber illumination is also used for decorative applications, including signs, art, and artificial Christmas trees. Swarovski boutiques use optical fibers to illuminate their crystal showcases from many different angles while only employing one light source. Optical fiber is an intrinsic part of the light-transmitting concrete building product, LiTraCon.

Optical fiber is also used in imaging optics. A coherent bundle of fibers is used, sometimes along with lenses, for a long, thin imaging device called an endoscope, which is used to view objects through a small hole. Medical endoscopes are used for minimally invasive exploratory or surgical procedures (endoscopy). Industrial endoscopes (see fiberscope or borescope) are used for inspecting anything hard to reach, such as jet engine interiors.

An optical fiber doped with certain rare-earth elements such as erbium can be used as the gain medium of a laser or optical amplifier. Rare-earth doped optical fibers can be used to provide signal amplification by splicing a short section of doped fiber into a regular (undoped) optical fiber line. The doped fiber is optically pumped with a second laser wavelength that is coupled into the line in addition to the signal wave. Both wavelengths of light are transmitted through the doped fiber, which transfers energy from the second pump wavelength to the signal wave. The process that causes the amplification is stimulated emission.

Optical fibers doped with a wavelength shifter are used to collect scintillation light in physics experiments.

Optical fiber can be used to supply a low level of power (around one watt) to electronics situated in a difficult electrical environment. Examples of this are electronics in high-powered antenna elements and measurement devices used in high voltage transmission equipment.

Principle of operation

An optical fiber is a cylindrical dielectric waveguide that transmits light along its axis, by the process of total internal reflection. The fiber consists of a core surrounded by a cladding layer. To confine the optical signal in the core, the refractive index of the core must be greater than that of the cladding. The boundary between the core and cladding may either be abrupt, in step-index fiber, or gradual, in graded-index fiber.

Index of refraction

Main article: Refractive index

The index of refraction is a way of measuring the speed of light in a material. Light travels fastest in a vacuum, such as outer space. The actual speed of light in a vacuum is 299,792 kilometers per second, or 186,282 miles per second.^[9] Index of refraction is calculated by dividing the speed of light in a vacuum by the speed of light in some other medium. The index of refraction of a vacuum is therefore 1, by definition. The typical value for the cladding of an optical fiber is 1.46. The core value is typically 1.48. The larger the index of refraction, the more slowly light travels in that medium.

Total internal reflection

Main article: Total internal reflection

When light traveling in a dense medium hits a boundary at a steep angle (larger than the "critical angle" for the boundary), the light will be completely reflected. This effect is used in optical fibers to confine light in the core. Light travels along the fiber bouncing back and forth off of the boundary. Because the light must strike the boundary with an angle less than the critical angle, only light that enters the fiber within a certain range of angles can travel down the fiber without leaking out. This range of angles is called the acceptance cone of the fiber. The size of this acceptance cone is a function of the refractive index difference between the fiber's core and cladding.

In simpler terms, there is a maximum angle from the fiber axis at which light may enter the fiber so that it will propagate, or travel, in the core of the fiber. The sine of this maximum angle is the numerical aperture (NA) of the fiber. Fiber with a larger NA requires less precision to splice and work with than fiber with a smaller NA. Single-mode fiber has a small NA.

Multimode fiber

A laser bouncing down an acrylic rod, illustrating the total internal reflection of light in a multimode optical fiber.

Fiber with large (greater than 10 μm) core diameter may be analyzed by geometric optics. Such fiber is called multimode fiber, from the electromagnetic analysis (see below). In a step-index multimode fiber, rays of light are guided along the fiber core by total internal reflection. Rays that meet the core-cladding boundary at a high angle (measured relative to a line normal to the boundary), greater than the critical angle for this boundary, are completely reflected. The critical angle (minimum angle for total internal reflection) is determined by the difference in index of refraction between the core and cladding materials. Rays that meet the boundary at a low angle are refracted from the core into the cladding, and do not convey light and hence information along the fiber. The critical angle determines the acceptance angle of the fiber, often reported as a numerical aperture. A high numerical aperture allows light to propagate down the fiber in rays both close to the axis and at various angles, allowing efficient coupling of light into the fiber. However, this high numerical aperture increases the amount of dispersion as rays at different angles have different path lengths and therefore take different times to traverse the fiber. A low numerical aperture may therefore be desirable.

Optical fiber types.

In graded-index fiber, the index of refraction in the core decreases continuously between the axis and the cladding. This causes light rays to bend smoothly as they approach the cladding, rather than reflecting abruptly from the core-cladding boundary. The resulting curved paths reduce multi-path dispersion because high angle rays pass more through the lower-index periphery of the core, rather than the high-index center. The index profile is chosen to minimize the difference in axial propagation speeds of the various rays in the fiber. This ideal index profile is very close to a parabolic relationship between the index and the distance from the axis.

Single mode fiber

Fiber with a core diameter less than about ten times the wavelength of the propagating light cannot be modeled using geometric optics. Instead, it must be analyzed as an electromagnetic structure, by solution of Maxwell's equations as reduced to the electromagnetic wave equation. The electromagnetic analysis may also be required to understand behaviors such as speckle that occur when coherent light propagates in multi-mode fiber. As an optical waveguide, the fiber supports one or more confined transverse modes by which light can propagate along the fiber. Fiber supporting only one mode is called single-mode or mono-mode fiber. The behavior of larger-core multimode fiber can also be modeled using the wave equation, which shows that such fiber supports more than one mode of propagation (hence the name). The results of such modeling of multi-mode fiber approximately agree with the predictions of geometric optics, if the fiber core is large enough to support more than a few modes.

The waveguide analysis shows that the light energy in the fiber is not completely confined in the core. Instead, especially in single-mode fibers, a significant fraction of the energy in the bound mode travels in the cladding as an evanescent wave.

The most common type of single-mode fiber has a core diameter of 8 to 10 μm and is designed for use in the near infrared. The mode structure depends on the wavelength of the light used, so that this fiber actually supports a small number of additional modes at visible wavelengths. Multi-mode fiber, by comparison, is manufactured with core diameters as small as 50 micrometres and as large as hundreds of micrometres.

Special-purpose fiber

Some special-purpose optical fiber is constructed with a non-cylindrical core and/or cladding layer, usually with an elliptical or rectangular cross-section. These include polarization-maintaining fiber and fiber designed to suppress whispering gallery mode propagation.

Photonic crystal fiber is made with a regular pattern of index variation (often in the form of cylindrical holes that run along the length of the fiber). Such fiber uses diffraction effects instead of or in addition to total internal reflection, to confine light to the fiber's core. The properties of the fiber can be tailored to a wide variety of applications.

Manufacturing

Materials

Glass optical fibers are almost always made from silica, but some other materials, such as fluorozirconate, fluoroaluminate, and chalcogenide glasses, are used for longer-wavelength infrared applications. Like other glasses, these glasses have a refractive index of about 1.5. Typically the difference between core and cladding is less than one percent.

Plastic optical fibers (POF) are commonly step-index multimode fibers with a core diameter of 0.5 mm or larger. POF typically have higher attenuation co-efficients than glass fibers, 1 dB/m or higher, and this high attenuation limits the range of POF-based systems.

Process

Standard optical fibers are made by first constructing a large-diameter preform, with a carefully controlled refractive index profile, and then pulling the preform to form the long, thin optical fiber. The preform is commonly made by three chemical vapor deposition methods: inside vapor deposition, outside vapor deposition, and vapor axial deposition.^[10]

With inside vapor deposition, a hollow glass tube approximately 40 cm in length known as a "preform" is placed horizontally and rotated slowly on a lathe, and gases such as silicon tetrachloride (SiCl₄) or germanium tetrachloride (GeCl₄) are injected with oxygen in the end of the tube. The gases are then heated by means of an external hydrogen burner, bringing the temperature of the gas up to 1900 kelvins, where the tetrachlorides react with oxygen to produce silica or germania (germanium oxide) particles. When the reaction conditions are chosen to allow this reaction to occur in the gas phase throughout the tube volume, in contrast to earlier techniques where the reaction occurred only on the glass surface, this technique is called modified chemical vapor deposition.

The oxide particles then agglomerate to form large particle chains, which subsequently deposit on the walls of the tube as soot. The deposition is due to the large difference in temperature between the gas core and the wall causing the gas to push the particles outwards (this is known as thermophoresis). The torch is then traversed up and down the length of the tube to deposit the material evenly. After the torch has reached the end of the tube, it is then brought back to the beginning of the tube and the deposited particles are then melted to form a solid layer. This process is repeated until a sufficient amount of material has been deposited. For each layer the composition can be modified by varying the gas composition, resulting in precise control of the finished fiber's optical properties.

In outside vapor deposition or vapor axial deposition, the glass is formed by flame hydrolysis, a reaction in which silicon tetrachloride and germanium tetrachloride are oxidized by reaction with water (H₂O) in an oxyhydrogen flame. In outside vapor deposition the glass is deposited onto a solid rod, which is removed before further processing. In vapor axial deposition, a short seed rod is used, and a porous preform, whose length is not limited by the size of the source rod, is built up on its end. The porous preform is consolidated into a transparent, solid preform by heating to about 1800 Kelvin.

The preform, however constructed, is then placed in a device known as a drawing tower, where the preform tip is heated and the optic fiber is pulled out as a string. By measuring the resultant fiber width, the tension on the fiber can be controlled to maintain the fiber thickness.

Practical issues

Optical fiber cables

Main article: Optical fiber cable

In practical fibers, the cladding is usually coated with a tough resin buffer layer, which may be further surrounded by a jacket layer, usually plastic. These layers add strength to the fiber but do not contribute to its optical wave guide properties. Rigid fiber assemblies sometimes put light-absorbing ("dark") glass between the fibers, to prevent light that leaks out of one fiber from entering another. This reduces cross-talk between the fibers, or reduces flare in fiber bundle imaging applications.

Modern cables come in a wide variety of sheathings and armor, designed for applications such as direct burial in trenches, dual use as power lines, installation in conduit, lashing to aerial telephone poles, submarine installation, or insertion in paved streets. In recent years the cost of small fiber-count pole-mounted cables has greatly decreased due to the high Japanese and South Korean demand for fiber to the home (FTTH) installations.

Fiber cable can be very flexible, but traditional fiber's loss increases greatly if the fiber is bent with a radius smaller than around 30 mm. This creates a problem when the cable is bent around corners or wound around a spool, making FTTX installations more complicated. "Bendable fibers", targeted towards easier installation in home environments, have been standardized as ITU-T G.657. This type of fiber can be bent with a radius as low as 7.5 mm without adverse impact. Even more bendable fibers have been developed.^[14] Bendable fiber may also be resistant to fiber hacking, in which the signal in a fiber is surreptitiously monitored by bending the fiber and detecting the leakage.

Termination and splicing

Optical fibers are connected to terminal equipment by optical fiber connectors. These connectors are usually of a standard type such as FC, SC, ST, LC, or MTRJ.

Optical fibers may be connected to each other by connectors or by splicing, that is, joining two fibers together to form a continuous optical waveguide. The generally accepted splicing method is arc fusion , which melts the fiber ends together with an electric arc. For quicker fastening jobs, a "mechanical splice" is used.

Fusion splicing is done with a specialized instrument that typically operates as follows: The two cable ends are fastened inside a splice enclosure that will protect the splices, and the fiber ends are stripped of their protective polymer coating (as well as the more sturdy outer jacket, if present). The ends are cleaved (cut) with a precision cleaver to make them perpendicular, and are placed into special holders in the splicer. The splice is usually inspected via a magnified viewing screen to check the cleaves before and after the splice. The splicer uses small motors to align the end faces together, and emits a small spark between electrodes at the gap to burn off dust and moisture. Then the splicer generates a larger spark that raises the temperature above the melting point of the glass, fusing the ends together permanently. The location and energy of the spark is carefully controlled so that the molten core and cladding don't mix, and this minimizes optical loss. A splice loss estimate is measured by the splicer, by directing light through the cladding on one side and measuring the light leaking from the cladding on the other side. A splice loss under 0.1 dB is typical. The complexity of this process makes fiber splicing much more difficult than splicing copper wire.

Mechanical fiber splices are designed to be quicker and easier to install, but there is still the need for stripping, careful cleaning and precision cleaving. The fiber ends are aligned and held together by a precision-made sleeve, often using a clear index-matching gel that enhances the transmission of light across the joint. Such joints typically have higher optical loss and are less robust than fusion splices, especially if the gel is used. All splicing techniques involve the use of an enclosure into which the splice is placed for protection afterward.

Fibers are terminated in connectors so that the fiber end is held at the end face precisely and securely. A fiber-optic connector is basically a rigid cylindrical barrel surrounded by a sleeve that holds the barrel in its mating socket. The mating mechanism can be "push and click", "turn and latch" ("bayonet"), or screw-in (threaded). A typical connector is installed by preparing the fiber end and inserting it into the rear of the connector body. Quick-set adhesive is usually used so the fiber is held securely, and a strain relief is secured to the rear. Once the adhesive has set, the fiber's end is polished to a mirror finish. Various polish profiles are used, depending on the type of fiber and the application. For singlemode fiber, the fiber ends are typically polished with a slight curvature, such that when the connectors are mated the fibers touch only at their cores. This is known as a "physical contact" (PC) polish. The curved surface may be polished at an angle, to make an "angled physical contact" (APC) connection. Such connections have higher loss than PC connections, but greatly reduced back reflection, because light that reflects from the angled surface leaks out of the fiber core; the resulting loss in signal strength is known as gap loss. APC fiber ends have low back reflection even when disconnected.

Free-space coupling

It often becomes necessary to align an optical fiber with another optical fiber or an optical device such as a light-emitting diode, a laser diode, or an optoelectronic device such as a modulator. This can involve either carefully aligning the fiber and placing it in contact with the device to which it is to couple, or can use a lens to allow coupling over an air gap. In some cases the end of the fiber is polished into a curved form that is designed to allow it to act as a lens.

In a laboratory environment, the fiber end is usually aligned to the device or other fiber with a fiber launch system that uses a microscope objective lens to focus the light down to a fine point. A precision translation stage (micro-positioning table) is used to move the lens, fiber, or device to allow the coupling efficiency to be optimized.

Fiber fuse

At high optical intensities, above 2 megawatts per square centimetre, when a fiber is subjected to a shock or is otherwise suddenly damaged, a fiber fuse can occur. The reflection from the damage vaporizes the fiber immediately before the break, and this new defect remains reflective so that the damage propagates back toward the transmitter at 1–3 meters per second. The open fiber control system, which ensures laser eye safety in the event of a broken fiber, can also effectively halt propagation of the fiber fuse. In situations, such as undersea cables, where high power levels might be used without the need for open fiber control, a "fiber fuse" protection device at the transmitter can break the circuit to prevent any damage

Java ebooks

2008-11-08T05:32:00.000-08:00

This free java ebooks collection provides ebooks on java objects, java faqs, java awt, java plugin, java programming, java runtime, java script, java downloads, free java applets, java vm, java certification, java socket, java beans, java source code, java threads, java help, java database, java api, java 1.5, java file, java training, java developments, java tips and basic java web services.

Following are the free java ebooks collection (part 2nd) provided by this site

C Programming Ebooks

2008-11-08T05:16:00.000-08:00

C is a computer programming language developed by Dennis Ritchie in 1972. C language is general purpose structural programming language. C was developed for system implementation, but it is used for all general purpose applications. C is a machine independent and platform independent language and thus it is used in embedded micro controllers to super computers. Origin of C language was intended for UNIX systems, but later C language dominated as a powerful low level system implementation programming language.
In C programming, all codes are written in functions. Parameters can be passed to function by value, by reference, by name etc. C provides memory allocation such as static memory allocation, automatic memory allocation and dynamic memory allocation. C language uses C Standard Library. This library supports input, output, mathematical functions and time values, etc. C is primary used for implementing operating systems, embedded systems applications and in intermediate language.
In this posting i wish to provide free C programming language ebooks which will guide you to learn C programming language and there by you can develop low level system programs and can concentrate more on Embedded C programming.

The C Programming Language By Brian W Kernighan and Dennis M Ritchie View/Download
Writing Bug Free C Code View/Download
The C Book View/Download
Object Oriented Programming with ANSI C View/Download
ANSI C for Programmers on UNIX Systems View/Download
C Programming Tutorial (K&R Version) View/Download
The New C Standard: An Economic and Cultural Commentary View/Download
Object Oriented Programming with C View/Download
Rationale For American Standard for Information Systems: Programming C Language View/Download
Sams Teach Yourself C in 24 Hours View/Download
C Elements of Style View/Download
Introduction to C Programming View/Download
Programming in C: A Tutorial View/Download
The C Library Reference Guide View/Download
A Tutorial on Pointers and arrays in C View/Download
C Language Reference View/Download
Programming in C View/Download
Incompatibilities Between ISO C and ISO C++ View/Download
Programming in C : UNIX Systems Calls and Subroutines using C View/Download
C programming by Steve Holmes View/Download
Parallel Programming in C for Transputer View/Download
Beej's Guide to C Programming View/Download
Phil's C Course View/Download
C Programming Notes by Steve Summit View/Download
C programming Tutorial View/Download
An Introduction to GCC: for GNU Compilers GCC and g++ View/Download
Learning GNU C View/Download
The GNU C Library View/Download
The GNU C Programming Tutorial View/Download
The Objective C 2.0 Programming Language View/Download
Objective Oriented Programming and the Objective C Language View/Download
Numerical Recipes in C View/Download

Anna University question bank

2008-11-01T07:02:00.000-07:00

Check this link to get the curriculum and syllabus of departments like Computer Science, Electronics and Communication, Electrical and Electronics, Civil, Information Technology, Mechanical, Electronics and Instrumentation and few other departments.

AU syllabus and curriculum

Question bank for Computer Science (CSE) Department papers.

Total Quality Management

Theory of Computation

System Software

Principles of Management

Object Oriented Programming

Object Oriented Analysis and Design

Microprocessor

Internet Programming

Digital Signal Processing

Data structure and Algorithm

Digital Principle and System Design

DBMS

Cryptography and Network Security

Computer Networks

Data structure

Design and Analysis of Algorithm

Visual Programming

Principles of Compiler Design

Graphics and Multimedia

Operating System

Software Engineering

Software Quality Management

Analog and Digital Communication

Question bank for Electronics and Communication (ECE) department.

Transmission Lines and Wave Guides

Optical Communication

Microwave Engineering

Principles of Communication

Professional Ethics and Human Values

Environmental Science and Engineering

Electronic Circuits

Signals and Systems

Digital Image Processing

VLSI Design

Communication Engineering

Digital Signal Processing

Digital Electronics

Communication Theory

Computer Networks

Satellite Communication

Radar and Navigational Aids

Electromagnetic Theory

Linear Integrated Circuits

Digital Communication

Antenna Wave Propagation

Mobile Communication

Electronics Circuits II

Principles of Management

Question Bank for Electronic and Electrical Engineering (EEE) department.

Neural Networks and Fuzzy Logic Control

Control Systems

Electrical Energy Generation Utilization and Conservation

Power System Analysis

Solid State Drives

Control Engineering

Transmission and Distribution

Electrical Machines II

Electronic Circuits

Measurements and Instrumentation

Internetworking Technology

Question Bank for Information Technology (IT) department.

Date Warehousing and Mining

Visual Programming

Digital Principle and System Design

Operating System

Database Management System

Data Communication

Digital Image Processing

E-Commerce

Information Coding Techniques

Digital Signal Processing

Cryptography and Network Security

Web Technology

Principles of Management

Question Bank for Mechanical Engineering department.

Electronic Microprocessor

Kinematics of Machinery

Entrepreneurship Development

Question Bank for Civil Engineering department.

Applied Hydraulic Engineering

Strength of Materials

Mechanics of Soils

Surveying II

Highway Engineering

Question Bank for First Year students.

English

Engineering Physics

Engineering Mathematics

Engineering Chemistry

Question Bank for Electronics and Instrumentation Engineering department.

Principles of Management

Process Control

Biomedical Instrumentation

Electrical Measurements and Instrumentation

Industrial Instrumentation II

Analytical Instruments

Transducer Engineering

Digital Signal Processing

Digital Logic Circuits

Digital Image Processing

VLSI Design

Linear Integrated Circuits

Question Bank for Aeronautical Engineering department.

Principles of Management

Aircraft Structures

Mechanics of Machines

Aerodynamics

Theory of Elasticity

Experimental Stress Analysis

Aircraft Systems and Instrumentation

Aircraft Transportation and Maintenance Management

Human Fetal Stem Cell Therapy

2008-08-03T00:07:00.000-07:00

Human Fetal Stem Cell Therapy is a medical treatment whereby human Fetal Stem Cells (“mother” cells of the body) are transplanted into a patient. These cellular building blocks are usually administered intravenously (Fetal pluripotent hematopoietic stem cells) and subcutaneously (Fetal neuronal stem cells). It is a painless procedure, which takes place in approximately one hour, with no negative side effects.
The Fetal Stem Cell searches out, detects and then attempts to repair any damage or deficit discovered, as well as releases growth factors, which stimulate the body’s own repair mechanisms.

Fetal Cell Properties

· Human Fetal Stem Cell Therapy can be compared to a bone marrow transplant, which is known to be a successful treatment for a variety of malignant, autoimmune and genetic diseases. The primary advantage of Fetal Stem Cell transplantation is that unlike a traditional bone marrow, or umbilical cord blood stem cell transplant, there is no need for the difficult and at times futile attempt to find a donor match.

· The Fetal Stem Cell does not have antigenicity (a cellular fingerprint) therefore they can be given to anyone without any rejection phenomena, thereby eliminating the use of immunosuppressive therapy (drugs that suppress the much needed immune system).

· Graft versus Host Reaction (where the donor cells attack the recipient, a dangerous and potentially fatal complication of bone marrow and umbilical cord transplantation) does not exist in Fetal Stem Cell therapy.

· Due to their controlled ability to rapidly proliferate, and their immediate release of growth factors, the Fetal Stem Cells are capable of, at times, quickly reversing lost functions.

These properties of the Fetal Stem Cell allow for unique treatment intervention in a multiplicity of diseases for a large group of patients who up until now have not had any means for recovery.

Patient Benefits

A large number of patients have been treated with Fetal Stem Cell Therapy, with by current standards, remarkable physical and psychological improvements.The range of human diseases currently viewed as candidates for fetal stem cell therapy is enormous and is continually expanding.Although it is still considered to be an experimental treatment in the United States, Human Fetal Stem Cell Therapy has been performed in other countries. Medra, Inc. can make the arrangements for receiving the Human Fetal Stem Cell Treatment. At the present time the therapy is administered in the Dominican Republic. (A one hour and forty-five minute flight from Miami.)Rarely has a single treatment modality offered so much promise to those suffering from some of mankind’s worst afflictions.

Nanotechnology

2008-08-03T00:01:00.000-07:00

Nanotechnology can best be considered as a 'catch-all' description of activities at the level of atoms and molecules that have applications in the real world. A nanometre is a billionth of a metre, that is, about 1/80,000 of the diameter of a human hair, or 10 times the diameter of a hydrogen atom.
An early promoter of the industrial applications of nanotechnology, Albert Franks, defined it as 'that area of science and technology where dimensions and tolerances in the range of 0.1nm to 100 nm play a critical role'. It encompasses precision engineering as well as electronics; electromechanical systems (eg 'lab-on-a-chip' devices) as well as mainstream biomedical applications in areas as diverse as gene therapy, drug delivery and novel drug discovery techniques.
Because nanotechnology has opened up new worlds of possibility, it has spawned a proliferation of new terminology - a kind of nanospeak to the uninitiated. For example, the two fundamentally different approaches to nanotechnology are graphically termed 'top down' and 'bottom up'. 'Top-down' refers to making nanoscale structures by machining and etching techniques, whereas 'bottom-up', or molecular nanotechnology, applies to building organic and inorganic structures atom-by-atom, or molecule-by-molecule. Top-down or bottom-up is a measure of the level of advancement of nanotechnology. Nanotechnology, as applied today, is still in the main at what may be considered the more primitive 'top-down' stage.

A breakthrough that may herald the beginning of the 'bottom-up' stage of nanotechnology has been the discovery of spinning molecular structures. These may open the door to realising the holy grail of power generation and controllable motion at the molecular level, with huge applications for medicine and information technology.

Another feature of nanotechnology is that it is the one area of research and development that is truly multidisciplinary. Research at the nanoscale is unified by the need to share knowledge on tools and techniques, as well as information on the physics affecting atomic and molecular interactions in this new realm. Materials scientists, mechanical and electronic engineers and medical researchers are now forming teams with biologists, physicists and chemists.

ETHICAL AND SOCIAL CONSIDERATIONS*
Over thirty years ago 20th Century Fox took the moviegoing public (and Raquel Welch) on a "Fantastic Voyage." In this cinematic barn-stormer, a diplomat lay near death from a blood clot, until, through miraculous technologies, scientists shrank a 30-foot-long clot-busting metal ship to the size of a pin's head
Audiences shuddered and gasped as the miniature ship sailed through the bloodstream, encountering white blood cells that seemed as large as the Brobdingagian giants confronted by Gulliver on his travels. The ship's crew narrowly avoided destruction and its heroes were restored to normal size. It was a fantastic first step toward human dreams of shrinking medicine to microscopic size. Today at the cinema we are entertained by even more dramatic stories of kids shrunk to the size of ants and microscopic machines sent to infect the world. But is it just fiction?
In 2000, the barrier between man and machine is as thin as a strand from the double helix. As computer equipment, surgical tools and communications pipelines shrink ever smaller, the next step in engineering is to merge biological and mechanical molecules and compounds into really, really small machines. This will happen in many different ways, and it raises many new issues.

First, we are beginning to see life forms reduced to molecular codes. This means that in our lifetime, viruses and components of our own DNA are going to become a lot more portable. Today, the last samples of smallpox virus are locked away in a vault in Atlanta at the Centers for Disease Control and Prevention. Tomorrow, getting smallpox may be as simple as forwarding an e-mail attachment with the smallpox DNA code to a $5,000 DNA synthesizer. The portability of DNA also means that where you once thought of your DNA as a part of your body, tomorrow the DNA from any of your cells might be used to make a cloned embryo or to make a big sack of cloned tissue for transplantation.

Is it ethical to move life around this way, playing mix-and-match with bits from different animals and species? Should we create entirely new kinds of life from the molecule up? Would it be wrong to build a bacterial life form that depended on a machine for survival, such as battery-acid-powered carpet-stain-removal bacteria? Or is that no more problematic than executing billions of little yeast molecules to make a barrel of beer or a loaf of bread?

Second, enhanced DNA and computers are more and more becoming parts of our bodies. Millions watch as Captain Picard and the crew of the Starship Enterprise battle a genetically engineered race called The Borg, who are the ugliest possible combination of DNA with computers (with the exception, of course, of new Borg sex symbol, Seven of Nine).

The Borg aren't real, but human-machine integration isn't just fiction anymore. Teams at MIT, Xerox and elsewhere are racing to connect you very closely to your cell phone and television. Within a few years, pacemakers and other medical devices will begin corresponding electronically with hospitals, physicians and even insurance companies about the patients whom they "inhabit." Many aspects of our behavior will be monitored more closely, and we may even get insurance discounts if we agree to "show" what healthy people we are!

Ethical issues in merging with computers go beyond the "weird" factor into a whole new kind of problem: what happens if human beings are made from non-human parts? Is a baby made from cloned DNA, gestated in a bubble and connected to a cellular phone still human? The answer matters because it is no longer obvious what it means to call something or someone "normal" or a "person," even in the world of medicine. That means it is getting harder and harder to figure out which advances in medicine are worth public research money and which ought to be mothballed.

Most interestingly, we are approaching the world of Fantastic Voyage. Experts in this new field of nanotechnology promise a world in which very small machines literally circulate within us, pursuing bad bacteria and viruses and dissolving cholesterol and lipids. It sounds great, if a little bit spooky, but it is still a long way away.

So should we spend taxpayers money on clot-breaking machines to extend the average life span, or work to build other artificial devices much smaller - and more effective - than the artificial heart of the 1970s? It is a difficult decision but one that only our generation can make.

Saving Social Security takes on a whole new meaning in a world that works hard to keep people alive well into their 100s, but connected to dozens of expensive little machines. As we prioritize about hunger, our status as a global power and the future of medicine, many of the most troubling decisions will be very, very small.

History Timeline of Robotics

2008-08-02T23:53:00.000-07:00

History Timeline of Robotics

1920
Czechoslovakian playwright Karel Capek introduces the word robot in the play R.U.R. - Rossum's Universal Robots. The word comes from the Czech robota, which means tedious labor.

1938
The first programmable paint-spraying mechanism is designed by Americans Willard Pollard and Harold Roselund for the DeVilbiss Company.

1942
Isaac Asimov publishes Runaround, in which he defines the Three Laws of Robotics.

1946
Emergence of the computer: George Devol patents a general purpose playback device for controlling machines, using magnetic recording; J. Presper Eckert and John Mauchly build the ENIAC at the University of Pennsylvania - the first electronic computer; At MIT, Whirlwind, the first digital general purpose computer, solves its first problem.

1948
Norbert Wiener, a professor at M.I.T., publishes Cybernetics or Control and Communication in the Animal, a book which describes the concept of communications and control in electronic, mechanical, and biological systems.

1951
In France, Raymond Goertz designs the first teleoperated articulated arm for the Atomic Energy Commission. The design is based entirely on mechanical coupling between the master and slave arms (using steel cables and pulleys). Derivatives of this design are still seen in places where handling of small nuclear samples is required. This is generally regarded as the major milestone in force feedback technology.

1954
George Devol designs the first programmable robot and coins the term Universal Automation, planting the seed for the name of his future company - Unimation.

1959
Marvin Minsky and John McCarthy establish the Articifical Intelligence Laboratory at MIT.

1960
Unimation is purchased by Condec Corporation and development of Unimate Robot Systems begins.
American Machine and Foundry, later known as AMF Corporation, markets the first cylindrical robot, called the Versatran, designed by Harry Johnson and Veljko Milenkovic.

1962
General Motors purchases the first industrial robot from Unimation and installs it on a production line. This manipulator is the first of many Unimates to be deployed.

1963
John McCarthy heads up the new Artificial Intelligence Laboratory at Stanford University.

1964
Artificial intelligence research laboratories are opened at M.I.T., Stanford Research Institute (SRI), Stanford University, and the University of Edinburgh.

1964
C&D Robotics founded.

1965
Carnegie Mellon University establishes the Robotics Institute.

1965
Homogeneous transformations applied to robot kinematics - this remains the foundation of robotics theory today

1967
Japan imports the Versatran robot from AMF (the first robot imported into Japan).

1968
Kawasaki licenses hydraulic robot design from Unimation and starts production in Japan.

1968
SRI builds Shakey, a mobile robot with vision capability, controlled by a computer the size of a room.

1970
Professor Victor Scheinman of Stanford University designs the Standard Arm. Today, its kinematic configuration remains known as the Standard Arm.

1973
Cincinnati Milacron releases the T3, the first commercially available minicomputer-controlled industrial robot (designed by Richard Hohn).

1974
Professor Victor Scheinman, the developer of the Stanford Arm, forms Vicarm Inc. to market a version of the arm for industrial applications. The new arm is controlled by a minicomputer.

1976
Robot arms are used on Viking 1 and 2 space probes.Vicarm Inc. incorporates a microcomputer into the Vicarm design.

1977
ASEA, a European robot company, offers two sizes of electric powered industrial robots. Both robots use a microcomputer controller for programming and operation.

1977
Unimation purchases Vicarm Inc.

1978
Using technology from Vicarm, Unimation develops the PUMA (Programmable Universal Machine for Assembly). The PUMA can still be found in many research labs today.

1978
Brooks Automation founded

1979
Sankyo and IBM market the SCARA (selective compliant articulated robot arm) developed at Yamanashi University in Japan

1981
Cognex founded.

1981
CRS Robotics Corp. founded.

1982
Fanuc of Japan and General Motors form joint venture in GM Fanuc to market robots in North America.

1983
Adept Technology founded.

1984
Joseph Engelberger starts Transition Robotics, later renamed Helpmates, to develop service robots.

1986
With Unimation license terminated, Kawasaki develops and produces its own line of electric robots.

1988
Stäubli Group purchases Unimation from Westinghouse.

1989
Computer Motion founded.

1989
Barrett Technology founded

1993
Sensable Technologies founded.

1994
CMU Robotics Institute's Dante II, a six-legged walking robot, explores the Mt. Spurr volcano in Alaska to sample volcanic gases.

1995
Intuitive Surgical formed by Fred Moll, Rob Younge and John Freud to design and market surgical robotic systems. Founding technology based on the work at SRI, IBM and MIT.

1997
NASA's Mars PathFinder mission captures the eyes and imagination of the world as PathFinder lands on Mars and the Sojourner rover robot sends back images of its travels on the distant planet.

1997
Honda showcases the P3, the 8th prototype in a humanoid design project started in 1986.

2000
Honda showcases Asimo, the next generation of its series of humanoid robots.

2000
Sony unveils humanoid robots, dubbed Sony Dream Robots (SDR), at Robodex.

2001
Sony releases the second generation of its Aibo robot dog.

2001
Built by MD Robotics of Canada, the Space Station Remote Manipulator System (SSRMS) is successfully launched into orbit and begins operations to complete assembly of International Space Station

mpressive Lines

2008-06-16T08:07:00.000-07:00

Found a reason to be strong.

You are the one

Always in my heart, my friend.

Every time you call my name,

I will be there

No matter how far, we are friends!

A Friend means

No matter how far you are live apart!

No matter how many years you couldn’t see!

Its a life long treasure, Cherish it!

Never ever forget about it!

The above lines are dedicated to all my frends……

Stay in touch….

Something from these Quotes

2008-06-16T07:58:00.000-07:00

1) Never expect things to happen.. struggle and make them happen.
never expect yourself to be given a good value
create a value of your own

2) If a drop of water falls in lake there is no identity.
But if it falls on a leaf of lotus it shine like a pearl.so
choose the best place where you would shine..

3) Falling down is not defeat...
defeat is when your refuse to get up...

4) Ship is always safe at shore... but is is not built for it

5) When your successful your well wishers know who
you are when you are unsuccessful
you know who your well wishers are

6) It is great confidence in a friend to tell him your faults;
greater to tell him/her

7) "To the world you might be one person,
but to one person you just might be the world

8) "Even the word 'IMPOSSIBLE' says 'I M POSSIBLE' "

9) Effort is important, but knowing where to make an effort in your
life makes all the difference.

May God Bless You All,

Never take some one for granted,Hold every person
Close to your Heart because you might wake up one day and realise
that you have lost a diamond while you were too busy collecting stones."
Remember this always in life.