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What is MOSFET: an Note on MOSFET: MOSFET Operation and details

February 26th, 2011 Remo No comments

First what is MOSFET: MOSFET stands for Metal Oxide Semiconductor FET. This device has same characteristics about FET i.e. same as FET but having a MOS structure. For MOSFET there are 2 types. One is enhancement type MOSFET and other is Depletion type MOSFET.

Depletion type MOSFET are normally ON device and Enhancement type MOSFET are normally OFF device and we can make enhancement MOSFET ON after we apply some voltage at the gate terminal greater than threshold voltage of the device. So the minimum voltage required to make the device On is called the Threshold voltage of the device. Now Depletion type of MOSFET is just the reverse of that ,this device is normally ON

device and by proper gate voltage this device can be made OFF.

About the structure of the MOSFET.

There are n-channel enhancement type MOSFET and p-channel enhancement type MOSFET.For n-Channel enhancement type MOSFET there is a p-substrate and within the p substrate there are 2 n+ regions are diffused .These 2 n+ regions will be source and drain. In between the source and drain there is a gate region. The structure of gate is Metal/Polysilicon then oxide and then p substrate.

Now the characteristics curve for the n-channel MOSFET are same as that of FET only in the curve there is a voltage at which gate to source voltage the device will remain in off state- I mean no current will flow when the device have gate to source voltage below the threshold voltage.

Now for the depletion type MOSFET there is a pre-existed channel in between the source and drain so forming a channel.There is a preexisted channel between the source and the drain that’s why when there is no gate to source voltage still we will get some current if some drain to source voltage applied.So this device is normally ON device.

Now there in depletion mode transistor say for n-channel depletion mode transistor FET i.e. MOSFET there is preexisted channel , this channel is made by ion implantation to implant some ions /electrons within the channel region that’s why the device is normally ON. Now when the proper gate to source voltage is applied then the device can be made OFF.

Method-3:Finger print recognition project

February 26th, 2011 Remo No comments

Now this method is a little bit harder. But what are the advantage if you can do this hard part then what are the advantages ?
According to me the advantage is tremendous.
You can have your own web shop/business etc shop for selling the authentication devices, attendance systems etc.
But what are the hard parts ?
What are the price ?
Hard parts are that you need to be expert with microcontroller and interfacing and need to be a good student with a capability to read and learn almost any circuit ,computer programming etc terms by yourself without anybody’s help, because at this level almost nobody will help you as this may be an industrial product and when the term comes money then nobody will give you the code etc and  t even not tell anything about that.
I am here giving a rough idea  about what you  need and how to do that..
You need to have a camera (  not web cam rather small standalone camera chips or image sensor chips ) then image sensor chips driver need to be written for  microcontroller. May be you need to go for a better microcontroller like PowerPc or ARM etc. Then after that on that microcontroller you need to implement the finger print algorithm .
So this is the way. The  price of single camera chip not so low, may be more that $30.
Then you need to learn the microcontroller because some advanced microcontroller needed in this case.

Is there any other way ?
Instead of microcontroller you can use DSP chips may be TMS 6711 chips by Texas instruments and write a camera driver in code composer studio and also implement the algorithm for finger print in that TMS series DSP chips.

securedownload

FPGA based approach:
In this  approach of the design we need to learn Verilog language very well. Then apply the hardware knowledge to design the  finger print recognizer engine. Then implement the algorithm using verilog  compiler and the use a CPLD/FPGA to download the code to.You may use Xilinx ISE webpack to download your code to the FPGA kits manufactured Xilinx corporation. Now obviously you need to write the camera driver if you use standalone camera for that.
Other Links for same project implementation

Method-1

Method-2

Finger print recognition :Method 2 of implementation

February 26th, 2011 Remo No comments

Now in this method of implementation you can do this by DSP processor.

So what are the things required here ?

Obviously you need to study and understand the algorithm very well. Then you require the DSP processor for as a hardware. Now Texas instruments DSK board can serve well for this purpose.

There is also a software comes with the DSK board called code composer studio, so within that code composer studio you can write the finger print recognition algorithm in C and then can download that code to the DSK board.

The DSK board contains the DSP processor and many other peripherals.

So what are the things you need?

Your DSK board should interface with the PC and via PC you will take the image of finger via web cam and the send that image to DSK board and then recognition tasks are done by the DSK board and you may glow a red LED on when there is a mismatch and a green LED when there is a match.

Now a little bit more deep. Explanation ?how DSK board will communicate with the PC ?If you see the code composer manual you can easily found the code to communicate between PC and DSK board via serial or parallel port.

Now take a snapshot or image via the web cam software and save that to some where. Then code composer studio environment run the program to read that that file and extract the raw image pixels and then those raw datas are send to DSK board to process(i mean the finger print recognition processing).

So this way using DSK board you can recognize finger print.

For method 3 see the next article.

Categories: Electronics project idea Tags:

A fingerprint recognition project idea for the BTech /BE final year

February 26th, 2011 Remo No comments

This project idea may be taken for the B.Tech final year project .So this project may have many applications like security ,user authentication ,attendance systems etc.

So this project may have a good impact for the engineers in the view of practical implementations as well as in the case of research etc.

So what are the things you need to know before you start this project?

First you need to have some idea about digital image processing ,i mean the theoretical ideas about image matching etc and basic image processing ideas.

Then for the practical implementation point of view you need to have the idea of handling the microcontrollers and the DSP processors and image sensor and interfacing with the microcontroller.

Now I will discuss the different possible ways for the implementation of the fingerprint matching or recognition system based on your field of expertise.

Following are the possible ways for the implementation.

Method-1:

Take a simple PC and an web cam. Make a box and illuminate that box and fit the web cam inside the box. so that when you place your finger on the top of box the distance between the web cam and your finger not be to be too far.

Note the box should be a closed box with a small opening where you place the finger and the web cam .The aim is to take the image of the finger. I want the still image of the finger then do the processing on the PC side using some programming language.

Now in PC side what are the software required and how to interface etc done on PC ?

Note in PC the web cam driver if installed then all OK ,you can run the software provided with the web cam and then take a snap shot for the finger.

Now note that your camera should be GOOD resolution camera (its very easy to get that because when i am writing the article at that time 8MP to 10 MP cameras or web cams are available possibly).Now on the software side you need to know the finger print matching algorithm and then need to implement that. Now question is where i get the finger print recognition algorithms ? Just search google and you will get plenty of algorithms .Then read it very carefully. These algorithms are research level so not very easy to understand. So read with the help of your teacher who is teaching image processing and learn the algorithm then try to implement that.

Now how do i implement.?

What are the things that you need to remember when going to implement that algorithm.

First as i said the method may be just take the picture using the tools provided with the web cam using web cam software provide with the web cam driver CD.

The your program will take the picture then extract features etc and then compare that with the image database that you have and then decide whether there is a match or no match.

Now you may ask how to make the image database? That things you will get in the fingerprint recognition algorithm paper(i mean journal paper).

So this way what are the software available to do that.

You can use C ,VC++ or any programming language .

Best to use MATLAB for doing that.

Now if you want to develop a software that automatically snapshot and then runs the algorithm and decide whether it is a fingerprint match or not then the you need to do with VC++ or .NET etc.

But that requires 1-3 years of professional software development experience on that environment(VC++ etc),but if you can do that then that may be a commercial product.

Obviously carry a more significant.

Other method of implementation is below.

Method 2 follows in this link:

Categories: Electronics project idea Tags:

an-anti-collision-systems-for-railways-GPS/GPRS based:part-2

February 26th, 2011 Remo No comments

This article covers another hi- tech ways of preventing the railway train collision .

The system consists of the following parts GPS device, a transmitter (may be GSM based),and a decision maker  an, display etc.

Now how the system installed? Each train consists of GPS device
Each GPS device and systems associated with that have database  for rail line tracks and their locations. They have some Gsm/GPRS link also so after a particular time intervals the GPRS device sends the location information of that train to the main server which is situated  to some central portion under some management. You can consider a central server which have all the location information of railway tracks. So when ever the GPS +GPRS device sending the information (location information) to the central server then from that location information it can be found that whether 2 trains locations approached to a collisionable    distance or not ,if so then a command or signal may be issued from the central server after deciding that and send to the corresponding Trains via GPRS link. So by using this a train can remotely be stopped also. Note trains also send their Ids to central server so that the server can identity which train is at what location now. Next few situations need to be considered. First when two trains passing side by side as tracks are not far so that distance may also be considered as collisionable  distance  and wrong alarm may be generated.
So to avoid this each train path is need to be prefixed and tracks need to have unique ID. For example say “from station :Hariana” to next 200 km if  tracks are uninterrupted then they are given a track no and unique track ID for each track.

Then to build the database of the tracks I mean which track has what GPS location info ,just a trolley or test engine which has GPS device installed run on a track and GPS location information are send via the GPRS link to the central server, this way server   may have created the data bank for that track and can uniquely identify the track through which the   test engine is moving.

Then whenever the actual Train is moving on that track and when ever this train’s engine sending the GPS info of location to the central server via GPRS link then server can easily search the data base and can identify through which track this train is currently moving. Is that track is the allocated track of the train or by some signalling mistake this train has gone into some wrong track ,so that can immediately be identified and can be tracked. So this is the simple idea ,now rest the things i mean the implementation details involved is not easy and many test runs are required as well as the collaboration with the Govt. Is required. Please NOTE:GPS devices available give a little bit error always like 10 meter to 100 meter (can vary).So we  need to take account that also, may be more than one GPS device can be used and from their data actual location may be extracted.

For more information on this type of project:

See More here

How to prepare for JEE examination: An experts guide for success

February 24th, 2011 Remo No comments

So to prepare for the IIT JEE following are some suggestions.
But take it from me that only the last night study is never sufficient to get a good marks/Rank in the JEE examination as for that you need to prepare for a long time .
So what are the ways to prepare for that very examination that can change your life -i mean change your life means- can have a good track in your life and in future based on that you may get your favourable subject to study for—in the engineering and technology.
Before that keep in mind you need to prepare   for the board examination as well before you appear for the JEE or the AIEEE.
So need to know the basic differences for that.Board examinations are for the basic concepts , the examinations   and the syllabus are arranged in such a way that you gain the basic concepts about the subjects and then appear for the examination. In JEE examination are mainly application oriented i.e what ever knowledge on basics on different subjects like physics ,chemistry and biology or mathematics you got need to be applied in problems.
So must give special stress on problem solving based on basic concepts
So need to understand that JEE is just the extension of the board examinations.
So basic task for the preparation is that read a chapter ,try to understand the chapter very well then try to grab a good concept on the chapter you just read then ask yourself about what ever portions are not clear to you. Then read those portions again and again to get a good grab on those blurred topics.
Then after you think you have  gained a good concept on that chapter you just read-go on solving few problems on that chapter and after you do a little bit of problems on that book ,move to a different writer’s book and on same chapter try to solve the problems given on that book’s (same chapter).Then make your target as that you will try to solve all the problems ,after that move to questions etc and try to answer the questions by yourself.
If you have correctly answered all  the questions then you can think that your conception is good.
To know whether your answer is OK or not try y to consult your teacher.

Now talking about the mocks tests: MOCK tests are they helpfull ?
My answer is yes, MOCK test are helpful only if you have prepared for the MOCK test each time ,So each time before appearing for the MOCK test just prepare by thinking that you are going to sit for a real test or JEE examination. Then sit for the MOCK test and then after that see how you performed on that test. Now  sit and think what are the problems, what mistakes  you made and how to cope with those mistakes you made so that next time you should not do any mistakes on the same.
So the purpose of the MOCK is to improve yourself not for just to sit in MOCK. Monitor your performance each time, your performance should increase.
I suggest not to take  more than one test per week.
.
So basic thing is take the test, analyse the results and then correct yourself and prepare for the next examination, this way you will be advanced to more better performance each time.
Now i think study on previous years questions papers is a good idea, then you will be able to judge yourself that how much you can answer for that examination.
I prefer not to waste your time by discussing the things which you can’t solve with your friends rather try yourself with the help of your teacher.

Categories: Education Tags: ,

Food recipe:Kosha Magsho and Vetki Bread

February 23rd, 2011 Remo No comments

Kosha Magsho

What we need(ingredients):

2-3 kg mutton

260 gm ginger

100 gm garlic paste

110 gm red chilli power

500 gm tomato paste

Salt to taste

3 onions

7 bay leaves

1.4 kg refied oil

5 pieces of luchi

 

How to do

Method of preparation

 

Take the mutton,ginger,salt,garlic paste,red chilli power and refined oil  in a bowl and marinate well.Now put this bowl in frigerator for 1 hour

Take a Kadhai which is deep enough ,and heat the  kadhai after adding refined oil and boil it.After taking the bay leaves and  then slice the onions and  then put into the kadahi,heat it until the color turns into golden brown.

Then add tomato paste and cook it, cook till the amount of tomato paste is half the previous amount, I mean the   amount taken initially getting halved.

Then add the marinated mutton into the kadhai and cook as required .When cooking of the mutton is done pour it o   on another pot.

Use chilli flakes and serve with the luchi .

So this is how tulip sehll(Luchi) and KOSHA MAGSHO can be prepared and served with the luchi.

 

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A new recipe for Bhetki and bread.

 

What are the ingredients?

8 pieces of 1.5 inch squared sized vethki  bhetki pieces.

110 gram sour curd

35 gm ginger pasted form

4-6 piecs of gondhoraj lebu

20 ml refined oil.

5-8 pieces of white bread slices.

 

How to prepare this item(Method of preparation)

 

.

First of cut the gondhoraj lime and get the juice in a pot.

Next we have to prepare a mixture .

The mixture contains chilli paste(20 gm) ,lime juice,ginger paste and salt.Then bhetki  fishes are taken into this mixture and marinated for for 15 minutes.

Now take the curd in a bowl and put all the mixture prepared there and the mix it for 15 minutes.

Put the fishes into the curd and keep for atleast 15-20 minutes.

 

Now how to serve?

Take a steal plate and take 2 pieces of fish at a tm time.

Then take a banana lead leaf and steam in steamer for 8-10 minutes.

Then add bread and serve.

 

 

 

 

 

 

Categories: Food and recipe Tags:

How to Make Ilish and kumropata tarkari and Tulip shell (Luchi)

February 23rd, 2011 Remo No comments

What wee need:

2-3 pieces of Hilsa fish

75-80 gn  gram mustard paste

25-30 gram chilli paste

40 gram card

40 gram curd

 

250 gram rice

15-20 ml lemon juice

Sorry

15-20 ml lime juice

20 gram musterd oil.

Salt(upto taste)

40 gram mango

pickle20 gram coconut paste.

5 gram turmeric

6-8 pieces of pumpkin leaves

 

How to make:

Take the fish pieces in a pot and the apply salt,lime,turmerica and mix it and left it for 10-15 minutes.

Take steel or plastic or glass bowl and put all the ingredients (donot take the pumpkin  leaves).

This a way prepare a marinade of mixture.

Now apply spice mixture over the fish pieces after 15 minutes.

And cook the hilsa fish  in the same way as boneless ilish  fish is cooked.

After the cooking you can slice the ilish pieces.

 

Now it’s the turn to use pummkin leaves .Just put a little bit of salt over the leaves ,keep for 10-12 minutes.Put the pumpkin leaves on the top of the preparation. Mix with the rice and serve hot.

 

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Tulip shell:(Luchi how to make )

What we need(ingredients)

1.5 Kg flour ,25 gram salt,180 gram refined aoil and some more for frying.

 

How to do it:

After sieving the flour we need to masked  –we need to make a well in the center and add oil and salt. After adding the water prepare a dutch.sorry prepare a dough.

Cover the dough with wet clothe and keep for 1  hour.

After 1 hour need to knead the dough and cut into 35 equal pieces.

Shape them into balls and apply oil generously-use a tray to store it and cover   with a moist cloth. Take  Kadhai and and boil some oil,  roll individual portions into circles of 5 inch diameter .Then need to fry the portions which you have rolled;.

After draining the oil remove .

 

After done serve them hot.

 

So this is how to make luchi which may be served with kosha magsho .

That’s a great food to taste with.

 

 

Categories: Food and recipe Tags:

Harbhajan singh’s likings:An Interview

February 23rd, 2011 Remo No comments

HarVajan Singh:A small report on his likings etc

Harbhajans Singh is one of the best cricketer that India have.

His spinning and bowling is incredibly good and can make many more matches to win in favor of India.

Here are some likings etc report for the Harbhajan sigh.all therse are collected from different news papers,Interviews at different times given by the Bhajji.

 

 

He like to play in Eden gardens with huge crowd support and he enjoys that.So he is a little bit upset when he heard possibly India is not going to play in eden gardens in 2011 world cup.

 

His favorite Eden Garden Memories:

He had a a hatrick on eden  garden as well as become the first Indian to get a hatrick on test match.

Winning the game against Australia in 2001 also pleased him too much.

 

He also liked that India beated south Africa  in Feb 2010 and become the number 1 team in test cricket.

 

 

When asked about  him about the legend sachein tendulekar he said that he met  with sachin on 1996 at the nets of Mohali,he also considered that moment as his one of the biggest moment he ever had.At that time he was young and called to bowl at the Indian net.He termed sachin as a great motivator as well as a role model.

 

Who is Bhaji’s favorite spin bowler ??

According to him his favorite bowlers (spin bowlers) are Muralitharan,Anil Kumble,Saqlin  Saqlain Mushtaq.

 

Bhajji said Vivian  Richards is one of the player for  whom he his ready to pay and watch his match even if it’s an exhibition match.

Bhajji is associated with Reebock and using their ZuigTEch Bats.

 

He also likes other sports like tennis and Roger Federer is his favorite.

His favorite actress :Madhuri Dixit.

 

He likes the following Bengali dishes

MistiDoi,Rasgulla

 

Categories: News Tags:

Jeet:Tollywood actor is going to be married soon

February 23rd, 2011 Remo No comments

Ok so the busiest tollywood hero is  going to be married. Now this report is based on a interview taken by some reporter  and published in some  magagazine/newspaper.

Why he opt for settled marriage ?

As the actor said that he  always a liked the arranged marriage .Then he said that he left the responsibility to choose the right partner for him to his parents as he know that parents will always choose the best for    him.

 

 According to the ACTOR Jeet the arranged marriage just like an adventure where many good phases has to be revealed after the marriage.People will discover each other after they marry.

 

 

When asked about that what his to be bride think about his profession then he said that his to be bride have seen few of his movies and they also discussed about that and she also respect his profession as well as she can be a good critic of his films .According to the Jeet the career of family background of both the families are almost the same and certainly this will help in adjusting the going to be relation ship between the two families.

 

How did Jeet found out his life partner?

 

As the actor said there was a lady in lucknow who was his sisters relative, According to the actor that lady suggested   him to marry the to be bride of jeet.

Then after the actor meets her, he begins to like her    and amazed to her simplicity and found that she can be fitted as his life partner.

 

When asked about that whether the actor thinks that his bride(to be) may come in film-then actor said that he don’t think so .

What is the date of the marriage:

As  the actor said it may be on February 2011.

Now  who is the  girl??

She is a lucknow based school teacher name Mohna.

We all welcome Mohna to WestBengal.

 

Categories: News Tags: