UNIX

History:
Unix was developed in 1969 at AT&T Bell Laboratories by Ken Thomson and Dennis Ritchie as a single user operating system in assembly language. The origin can be traced back to 1965, when a joint venture was undertaken by Bell Laboratories, General Electric Company and Massachusetts Institute of Technology known as MULTICS [Multiplex Information and Computing Service]. Later Unix was re-written in C in the year 1973.

The Unix filesystem:
In the Unix file system, the root [/] contains sub-directories viz. bin, boot, home, etc, user, dev and lib. In this system the Kernel resides on top of the hardware which provides the platform for Shell and Unix utilities and Application programs.

The various types of Unix Files are:
1. Ordinary or Regular Files [contains text, data or program information; not other files]
2. Directory Files [contains other directories or files; here each line comprises of two parts viz. the item name and the inode number(a pointer)]
3. Device or Special Files [physical devices as files; categorized into character special and block special files]
4. Symbolic Links [an indirect pointer to a file; categorized into hard link and soft link]

In Unix, the users can be categorized into various types according to their access control attributes. They are:
1.SuperUser
2.Owner
3.Group
4.Others

The various access attributes assigned to files or folders that provide the user some form of access control over the data are read[r], write[w] and execute[x].

Shells in Unix:
A Shell is nothing more than a command interpreter. In Unix, the shell is designed to be the interface to the user, to receive the user’s input(interpret commands) and act on them. The shell then sends the output to the default or a specialized location, usually the user’s terminal. There are some common Unix shells:

1. Bourne Shell: Unix shell program by Steve Bourne; “sh” or “/bin/sh”; has a “$” prompt.
2. Korn Shell: Newer variation of the shell program by David Korn; “ksh” or “/bin/ksh”.
3. C Shell: Commonly used shell by Bill Joy; has a “%” prompt; configured by *.rc and *.login files.
4. TC Shell: Variation of C Shell.
5. Bourne-Again Shell: Used in Linux; “bash”; has a “$” prompt; configured by *.bashrc file hidden in /home.

Recommended Books for ECE GATE

GATE in ECE – ELECTRONICS AND COMMUNICATION ENGINEERING

These are the books recommended for the different topics included in the GATE exam in ECE steram. But it is not necessary to study all the books listed for the a topic.

# PART A: ENGINEERING MATHEMATICS

* Higher Engineering Mathematics, Dr. B. S. Grewal
* Advanced Engineering Mathematics ,Erwin Kreyszig
* GATE Engineering Mathematics, Kanodia

# PART B: ELECTRONICS AND COMMUNICATION

1. Networks

* Network Analysis VanValkenburg
* Engg Circuit Analysis Hayt & Kemmerly
* Electric Circuits by Joseph A. Edminister
* Fundamentals of Electric Circuits – Sadiku

2. Electronic Devices

* Integrated electronics by Milman Halkias
* Micro Electronic Circuits by Sedra& Smith
* Electronic Devices And Circuits by David A Bell
* Electronic Principals by Malvino
* Electronic Devices And Circuits by Boylestead
* Solid State Electronic Devices By Benjamin G Streetman

3. Analog Circuits

* Electronic devices and circuits by Millman and Halkias
* Integrated Electronics by Millman and Halkias
* Electronic devices and circuits by Boylestad and Nashelsky
* Microelectronics by Millman and Grabel
* Analog Circuits by Sedra and smith
* Linear Ics and integrated circuits by Gaekwad

4. Digital Circuits

* Digital Electronics by Morris Mano
* Microprocessor by Ramesh Gaonkar
* Digital Principles and Design by Donald Givone
* Digital Circuits by Taub and Shilling
* Digital Electronics by Salivahanan

5. Signals and Systems

* Signal and Systems Simon Haykin
* DSP by Proakis and Manolkis
* Signals and Systems by Oppenheim and Schaffer
* Signals and systems by B.P.Lathi

6. Control Systems

* Modern Control system by Ogata
* Control System Engg Nagrath and Gopal
* Automatic Control System by B.C.Kuo
* solved problem in control system by Jairath

7. Communication Theory

* Communication System by Simon Haykin
* Principles of Communication system by Taub and Schilling
* Schaum series for solved problems
* Modern and Digital Communication system by B.P. Lathi

8.Electro Magnetics

* Engg Electromagnetics by William Hayt
* Elements of Electromagnetics by Mathew Sadiku
* Electromagnetic waves and Radiating system by Jordan and Balmein
* Electromagnetics by K.D.Prasad
* Microwave devices and circuits by Liao
* Schaum Series for solved problems

The Web Tutorial

w3 html and css

http://www.w3schools.com/html/
http://www.w3schools.com/css/default.asp

Simple HTML/CSS Layout Examples
http://blog.html.it/layoutgala/
http://www.code-sucks.com/css%20layouts/faux-css-layouts/
http://www.mycelly.com/
http://www.thenoodleincident.com/tutorials/box_lesson/basic2_fixed.html

CSS cheat sheet
http://www.google.com/search?hl=en&q=css+cheat+sheet&btnG=Search

HTML Cheat sheet
http://www.google.com/search?hl=en&q=html+cheat+sheet&btnG=Search

Group that standardizes html
http://www.w3.org/

MetaTags
http://www.google.com/search?hl=en&pwst=1&sa=X&oi=spell&resnum=0&ct=result&cd=1&q=meta+tags&spell=1
doctype
http://www.google.com/search?hl=en&q=doctype&btnG=Search

Free webhosts to upload your custom pages to.
http://www.tripod.lycos.com/
http://pages.google.com/
http://www.atspace.com/
http://geocities.yahoo.com/
http://www.bravenet.com/
http://members.freewebs.com/

RGB Color
You can indicate color by using RGB mode too. eg. #336699 is a nice blue google likes to use. It stands for 33 red, 66 green, and 99 blue in hexadecimal. Here’s a RGB color picker
http://www.siteprocentral.com/html_color_code.html

Domains cost money, like $10 a year usually or less. I’m not going to endorse any registrars.

CSS rounded corners
http://www.google.com/search?hl=en&q=css+rounded+corners&btnG=Search
Change the look when printing (media)
http://www.w3.org/TR/REC-CSS2/media.html

CSS Popular Pages
http://del.icio.us/search/?fr=del_icio_us&p=css&type=all
http://del.icio.us/search/?fr=del_icio_us&p=top+css&type=all

HTML Validator
http://validator.w3.org/

CSS Validator
http://jigsaw.w3.org/css-validator/

Some decent text editors
http://www.context.cx/
http://www.pspad.com/
http://notepad-plus.sourceforge.net/uk/site.htm
http://www.jedit.org/
http://www.scintilla.org/SciTE.html
http://www.notetab.com/

Html forums
http://groups.google.com/group/alt.html/topics?lnk=gschg

CSS Forums
http://csscreator.com/?q=forum/

Info about “Lorem Ipsum” often seen on template pages
http://en.wikipedia.org/wiki/Lorem_ipsum

CSS Transparency

1. IE filter:alpha(opacity=50);

2. Firefox -moz-opacity:0.5;

3. KDE based browsers -khtml-opacity: 0.5;

4. Safari opacity: 0.5;

Ten Rules For Being Human By Cherie Carter-Scott

1.You will receive a body. You may like it or hate it, but it will be yours for a lifetime.
2. You will learn lessons.You are enrolled in a full-time, informal school called “life”. Each day in this school you will have the opportunity to learn lessons. You may like the lessons or think them irrelevant and stupid.
3. There are no mistakes, only lessons. Growth is a process of trial and error, experimentation. The “failed” experiments are as much a part of the process as the experiment that ultimately “works.”
4. A lesson is repeated until it is learned. A lesson will be presented to you in various forms until
you learn it. Then you can go on to the next lesson.
5. These lessons will never end. There is no part of life that does not contain its lessons. If you are alive, there are lessons to be learned.
6. “There” is no better than “here.” When your “there” has become a “here,” you will simply
obtain another “there” that looks better than “here.”
7. Others are mirrors of your own self-image. You will be drawn to others for the positive qualities you
believe exist within you. In a similar way you will tend to hate others who reflect back to you those qualities you most fear in yourself.
8. What you make of your life is up to you. You have all the tools and resources you need; what you do with them is up to you. The choice is yours.
9. The answers are found within you. You already have the answers to life’s questions. Just
look, listen within, and trust your intuitive powers.
10. You will forget all this.

Glossary on Boilers

Flash Point is defined as the temperature at which a liquid fuel begins to generate vapours just enough to form an explosive or a mixture that is inflammable. Larger a fuel is volatile, lesser will be the flash point. This property, important for gasolines whose flash point is lower than ambient temperature, is termed Volatility.

Pour Point is defined as the lowest temperature at which a liquid will just flow or pour from a vessel.

Ignition Temperature is the lowest temperature at which combustion occurs with the mixing of the fuel in vapour form with oxygen in the surrounding air.

Flame Temperature is defined as the temperature attained by products of combustion when all the heat generated by the fuel is allowed to heat it at the original volume of the fuel, and no heat is allowed to be lost to the surroundings.

Flame Speed is the speed at which the flame will travel in a mixture of gaseous fuel and air.

Stoichiometric Combustion of a fuel is defined as the process of complete combustion of its constituents to the products of combustion with evolution of heat. The pre-requisite of any such phenomenon is the availability of the fuel in a gaseous state (when it can mix with the oxygen in the surrounding air) and the prevailing temperatures to be high enough so that the combustion reaction can take place leading to the release of heat energy.

Excess Air Factor is defined as the fraction of air required in excess of the theoretical amount.
Excess Air Factor= (actual air requirement – theoretical air requirement) / theoretical air requirement

Combustion Efficiency measures the effectiveness of the combustion reaction and is defined as
Combustion Efficiency = heat released during combustion / heat contained in the fuel

Effective Calorific Value is the effective heating value obtainable from a sample fuel which is much less than the net heating value. This is due to the partial oxidation of C to CO and some hydrogen remaining unoxidised.

Dryness Fraction of a gaseous mixture is the ratio of the mass of the steam in the mixture to the mass of the entire mixture.
Dryness fraction = mass of steam in mixture / mass of the mixture

Boiler Efficiency is the percentage of heat given out by the boiler to the heat supplied to the boiler.
Boiler Efficiency = ( heat given out by the boiler / heat supplied to the boiler ) * 100 %
= ( evaporation ratio * heat content of steam) / ( fuel rate * calorific value)

Maximum Continuous Rating is the design rating of working for which the efficiency of the boiler is maximum.

Heat Utilization Efficiency (HUE) Factor or Fuel Utilization Efficiency (FUE) Factor
= target fuel consumption / actual fuel consumption
where target fuel consumption = standard steam consumption / standard steam to fuel ratio

Weighted Average Combustion Efficiency
= ( Sum of the combustion efficiencies * average steam load ) / Sum of the average steam load

Absolute Pressure is the common gauge pressure plus the atmospheric pressure.

Caustic Embrittlement refers to the cracking of boiler steel occuring while the boiler is in service but not subjected to excessive pressure or temperature due to the boiler’s water being too caustic.

Life is JAVA

hi,sokol bondhuder janay amar antorik Hello ! ;)
kokhono ki tomra bhebe dekhecho je jibon r sathe JAVA r koto mil ache. :D
[NOTE:(amar je bondhura JAVA ki ta janena tader jonyo)JAVA ekta sohoj sorol (loke bole) sosta tikau (open source) programming language]
JAVA r kotogulo gunagun ache:jemon reusability, polymorphism, encapsulation,abstraction,inheritance.ebar jibon r songe mil khuje peyechi jokhon boltey hoy ki kore.
ami ekbar amar ek bondhuke subho noboborsher sms korlam.ektu badey dekhlam je sey sms tay tar kach theke fire elo.ami hotobak ektu.pore se bolle je tar kache r kono noboborsher sms chilona boley ei ghotona. amartay amake ferot dilo,eta ke bola jete pare "reusability".
ei jibon,tar modhye kotto lok,tader songe amader attyiota,alap,golpo,bondhutto....koto rokom somporko.kintu eki byakti kotojoner kache kotorokom bhabe birajoman,nanabidho somporke.onnobhabe dekhte gele eki byakti karo kache bhalo,karo kache ba mondo.eke bolay jete pare "polymorphism".
amra majhe majhe karo karo kach theke dukkho pay,aghat pay,kosto pay; mon e jeno ekta dag kata hoye jay,kintu se jonyo to r jibon theme gele cholbena.jibonke cholte hobey karon "Life finds its way" tay amra mon r ghobire sei smriti guloke lukiye rekhe diy,kono gopon sinduke tala bondi kore.bairer keu janteo parena tar byapare.majhe majhe jante chayleo na.eke bola jete pare "encapsulation".
amra jibone kotokichuy kori jegulor karon amra janina,janina ki bhebe korchi,tar ses e ba kothay.jibone ekbar prem korechilam.tokhon mone hoto jani keno korchi.ekhon mone hoy,kenoy ba korlam,er ses kothay tato janina,ajke bhabte bosle tolar juktigoto dikta bujhe uthte parina.obosyo loke bole prem bhalobasha jukti diye korena.kintu thik ache jibone onek kichuy ache jegulo amra karon ba ontoyfol na jeney kori.etake bola jete pare "abstraction".
jibone amra ja hoye uthechi ba ja achi ta amader baba maa er probhab fole.taray amader jogoter alo dekhiyechen.taray amaderke amader ei byaktisottya prodan korechen,amader ei sokol gunagun tar kach thekey pawa.eta key amra boli "inheritance".

Management, Science or Art?

Is Management a Science or an Art?

Management as a Science:

Science is a systematic body of knowledge acquired through rigorous method of collecting data, classifying and measuring it, setting up hypothesis and testing those. If the criteria for science is applied to management, it may be observed that:

* It is a systematic body of knowledge that deals with people.
* Its principles have been evolved over the years on the basis of continuous careful observations and experimentation.
* Its principles have universal application in every branch of human activity of a profit making as well as a non-profit making organisation.
* Its principles may not yield identical results or desired results when applied to different organizations at different times simply because human behaviour is ever changing and most unpredictable.

Therefore, management is not a exact science but some aspects of management are scientific.

Management as an Art:

The basic characteristics of Art are:

* Art is an application of theoretical knowledge gained.
* It involves deliberate and conscious effort on the part of the user to achieve goals.
* It requires some special skills on the part of the user.

If the above criteria are applied to management, it may be noted that:

* Management is the application of that human knowledge which deals with people.
* It applies deliberate and conscious efforts to achieve its objectives
* Management is creative. A manager like an artist needs to depend on his own experience, inner senses, intuition and judgement while taking decisions on any managerial problem.

Therefore, management is an art.