Explain and Solve : Round Robin (RR) of Operating System Concepts

If you haven't read/tried the earlier/other problems then click the links follow:

Round Robin: This method is quite same as the FCFS but the difference is the in this case the processor will not process the whole job (process) at a time. Instead, it will complete an amount of job (quantum) at a turn and then will go to the next process and so on. When all job has got a turn, it will again start from the first job and work for a quantum of time/cycle on each job and proceed. Now consider a CPU and also consider a list in which the processes are listed as follows,

Burst Time

Quantum = 2 Second

Explain and Solve : Priority Scheduling of Operating System Concepts

If you haven't read/tried the earlier problems then click the links follow:

Priority Scheduling: This method is quite same as the SJF but the difference is that instead of choosing the next process to work on by the shortest burst time, CPU chooses the next process by the shortest priority value. Here, all the processes are given a priority value. The process with the shortest (The most shortest is 1) priority will be worked on first and so on. Now consider a CPU and also consider a list in which the processes are listed as follows,

Burst Time

Mipony Download Manager - One of my favorite download managers. Download + Tutorial

Few days ago I said that I get resume of download from Mediafire/Megaupload/Filesonic, some of the audiences did not believe me. So, today I am writing about this Awesome Download Manager, Mipony.

This software is completely free, so download it now, install and run.

মাইপোনি ডাউনলোড ম্যানেজার -- আমার অন্যতম প্রিয় ডাউনলোড ম্যানেজার। ডাউনলোড + টি্উটোরিয়াল।

সেদিন বললাম যে মিডিয়াফায়ার/মেগাআপলোড/ফাইলসনিক এই ৩ টা সাইট থেকে ডাউনলোডিং এর সময় আমি রিজিউম পাই, অনেকের কাছেই ব্যাপারটা জানা ছিলো না। তাই ভাবলাম এই অসাম কমপ্লিট ফ্রি ডাউনলোড ম্যানেজার টা সম্মন্ধে লিখি।

সফটওয়্যারটার নাম, মাইপোনি ডাউনলোড ম্যানেজার। যেহেতু ফ্রি তাই নিশ্চিন্তে ডাউনলোড করে নিন, কোন ক্র্যাক/প্যাচ নেই।

Explain and Solve : Shortest Job First (SJF) of Operating System Concepts

If you haven't read/tried the earlier problems then click the links follow:

Shortest Job First (SJF): 

This method is quite same as the FCFS but the difference is the in this case the processor will not process the jobs (processes) as they will come. Instead, a scheduler after a complete cycle (consider this as a 1 second job done) will check which is the job with the shortest burst time right now and will work on that. Now consider a CPU and also consider a list in which the processes are listed as follows,

Burst Time

Explain and Solve : First Come First Served (FCFS) of Operating System Concepts

If you haven't read/tried the earlier problems then click the links follow:

First Come First Served (FCFS): CPU gets a lot of processes to handle. The problem is shortening the waiting time for a process to reach CPU and get processed. Now consider a CPU and also consider a list in which the processes are listed as follows,

Burst Time

আঞ্চলিক ভাষা। ভালো নাও লাগতে পারে, তাই বলে তামাশা করবেন না.....

এমন ভাবার দরকার নাই যে কেউ আজ আমাকে কটাক্ষ করেছে, মনের কষ্ট থেকে লিখছি। লিখার প্ল্যাণ সন্ধা থেকেই ছিলো শুধু একাম-সেকাম-আকাম-কুকাম করতে যেয়ে লেখা হয়ে ওঠেনি।

“ধূর ছাই” মার্কা একটি বিকাল, চড়কি ছাড়াই চক্কর খেলাম।

২৪ নভেম্বর ২০১১

দুপুর ৩ টায় আমার ট্রেনিং সেন্টারে যাওয়ার কথা। সেখানে আমি ওয়েব ডিজাইনিং এন্ড ডেভেলপমেন্ট প্র্যাকটিস করি। “ডিজিটেক ভ্যালী”, অলকার মোড়ে। বাড়ি থেকে বের হলাম, পকেটে মোট ২৩০ টাকা আছে। বাসা থেকে বের হয়ে মিছিল ঠেলে মিউজিয়াম মোড়ে পৌঁছালাম। সেখান থেকে ৪ টাকার সিগারেট ধরিয়ে ১০ টাকায় ভাড়া করলাম একটা রিকশা। অলকার মোড়ে পৌঁছে ভাড়া মিটিয়ে ট্রেনিং সেন্টারে ঢুকে দেখি ইন্সট্রাক্টর তখনো আসেননি। আমার সহপাঠীরাও নেই। ওয়েট করছি, পেপার পড়ছি, নেট ব্রাউজ করছি। ৪০ মিনিট পার হয়ে গেলো। বুঝলাম, ভাইয়া মিছিলে আটকা পড়ছে। কিছুক্ষণ পর আরেক ভাইয়া এসে সেটাই বললো। বের হয়ে আসলাম। পকেটে তখন ২১৬ টাকা। এর মধ্যে ২০০ টাকা দিয়ে আমার ৮ টা ব্ল্যাংক ডিভিডি কেনার কথা। বাকি ১৬ টাকার মধ্যে ১০ টাকা রিক্সা ভাড়া আর ৪ টাকার সিগারেট। ২ টাকা পকেটয় নমঃ। হঠাৎ.....

My First Use of JavaScript : A Basic Calculator.

Well, I found it that whenever I learn a language the first code I write is always a calculator. I have started taking tutorials on JavaScript few weeks ago to create my own blog, just for fun as I do software engineering on VB.NET platform mainly, that is my site of interest. However, web developing is always interesting to me and I also know that it has a very high level of hard-work and creativity included with it. I don't want to get to that much of details.

On the first day I learnt about using Textboxes, using their values, creating and using functions. Well after that our tutor asked us to do something with what we just learned. Then I wrote the very common 4 functions to do additions, subtractions, multiplications and divisions. Then took two textboxes to take input and another to show result. I also used 4 buttons for the previously mentioned 4 mathematical operations, clicking on each of them the corresponding function will be called. I know its very simple, but I enjoyed.

What I did is a following,

Describe the low pass filter.

Low Pass Filter : Considering the grey-scale values of a part of an image as below,
Here, we have taken 9 grey scale values. It is seen that the 5th value is very different than the other 8 values, that is a big change is occurring at that point due to the big change of the grey-scale value at that point than the other points.

Describe the fundamental steps of digital image processing with a neat block diagram.

Fundamental Steps of Digital Image Processing : There are some fundamental steps but as they are fundamental, all these steps may have sub-steps. The fundamental steps are described below with a neat diagram.

What is digital image processing?

Digital Image Processing : An image which has a two dimensional function of f(x,y), where x and y are plane co-ordinates and the amplitude of f at any (x,y) is called the grey level of the image at that point. When the values of these of an image are finite, discrete quantities then the image is called a digital image. ... 

Explain Cross Elasticity of Demand.

Cross Elasticity of Demand : Cross elasticity of demand occurs when a change in price of a commodity brings the change in demand of another commodity. The cross elasticity of demand for two goods X and Y, is the ratio of the percentage change of quantity purchased of X to the percentage change in price of Y.

            Cross elasticity of demand occurs for two goods which are interrelated, such as complementary goods, substitutable goods, etc. ... 

Explain Income elasticity of demand.

Income elasticity of demand : A persons demand for a good may change with his\her change in income. The income elasticity of demand is the ratio of percentage change quantity purchased per time to the percentage change in income. Thus,

Explain Price elasticity of demand

Price Elasticity of Demand : Price elasticity of demand measures the quantitative response of demand to a change in price. This is the ratio of percentage change in demand to the percentage change in price. So the price elasticity of demand is,

What is elasticity, elasticity of demand, elastic demand, and inelastic demand?

         Elasticity : In economics, elasticity is the ratio of the percentage change in one variable to the percentage change in another variable. Elasticity is a popular tool among empiricists because it is independent of units and thus simplifies the analysis. ... 

Show the market demand for a commodity with example and explanation.

Market Demand For a Commodity : The market demand for a commodity means the total demand for a commodity made by all the individuals in the market. The market demand for a commodity gives the alternative amounts of a commodity demanded per time period, at various alternative prices, by all the individuals in the market. It depends on all the factors as the individuals demand depends on. It is obtained by the horizontal summation of all the individuals demand curves for the commodity. ... 

What is shift in demand curve? Explain with example.

Shift in Demand Curve : Shift in demand curve means the change in demand curve. This change will have to be for the change in ceteris paribus. That is when the price of a commodity remains constant and the other things which can affect the demand of the commodity changes, a shift can be found in the demand curve. This shift may be either leftward or rightward, meaning the decrease in demand and increase in demand respectively. ... 

Explain the law of negatively sloped demand curve.

Law of Negatively Sloped Demand Curve:

            First, obtain the demand schedule; the formula is,

                                                Qdx = f(Px)

            Considering, an individual demand function for a commodity X is given by,

                                                Qdx =8 - Px    cet.par.

            Here, Qdx  is the quantity demanded and Px is the price of X commodity.

Draw and explain a demand curve by obtaining a demand schedule.

Obtaining Demand Schedule:

To obtain the demand schedule the formula is,

                                                Qdx = f(Px)

Considering, an individual demand function for a commodity X is given by,

                                                Qdx =8 - Px    cet.par.

Here, Qdx  is the quantity demanded and Px is the price of X commodity.

What is / Define Demand, Demand Schedule and Demand Curve.


The desire for a commodity of an individual or a group will be called their demand when they are able to pay for that commodity. That is demand is desire with account to pay.

What is opportunity cost? How / Is opportunity cost related with PPF?

Opportunity Cost:

Life is full of choices. Because resources are scarce, we must always consider how to spend our limited income or time. In a world of scarcity choosing one thing means giving up something else. If there is no increase in productive resources, increasing production of a first good has to entail decreasing production of a second, because resources must be transferred to the first and away from the second. 

What is production possibility frontier (PPF)? Explain.

Production Possibility Frontier (PPF) : In economics, a production possibility frontier (PPF) is a graph that shows the different rates of production of two goods that an individual or group can efficiently produce with limited productive resources. The PPF shows the maximum obtainable amount of one commodity for any given amount of another commodity or composite of all other commodities, given the society's technology and the amount of factors of production available. ... 

What are the differences between microeconomics and macroeconomics?

Differences Between Microeconomics and Macroeconomics: 

The study of economics is divided into microeconomics and macroeconomics by the modern economists. Both of them discuss the economical activities but are used in different sectors under different circumstances. In spit of having some similarities, they also have some differences which have been given below.

What are microeconomics and macroeconomics?

The study of economics is divided into microeconomics and macroeconomics by the modern economists. Both of them discuss the economical activities but are used in different sectors under different circumstances.

What are the three problems of economic organizations? How can the three problems of economic organization be solved in free and mixed economics?

Three Problems of Economic Organizations:

In every economy; economic organizations, irrespective of their type, have to face and solve three problems of economics. These three problems are as follows,

  1. What commodities are produced & in what quantities.
  2. How goods are produced.
  3. For whom goods are produced.

Description and solution to these problems in fee and mixed economies is given below.

Define Economics / Definition of Economics / What is Economics ?

          Economics : The word ‘Economics’ has been originated from the Greek word ‘Oikonomia’ which means ‘Management of household wealth’. As being social, humans face various wants and needs. Economics is all about those activities which occur to fulfill these wants and needs. In fact, Economics describes the economical activities of humans in daily life. Founder of Economics is Adam Smith. ... 

Define the term Solution / What is Solution in Chemistry?

       Solution : Whenever two or more than two non-reacting substances are mixed, the resulting system is called a mixture. A solution is a homogeneous mixture of two or more substances in their molecular level.

Draw the molecular structure of XeF2, XeF4, XeF6.

Xenon forms three stable fluorides, XeF2, XeF4, XeF6. The molecular structure of XeF2 is linear, that of XeF4 is square planar and that of XeF6 is pentagonal pyramidal. They are given in the following figure,

What are inert gases ? why are they so called ?

               Inert gases : The elements of the zero group of the periodic table are known as inert gases. They are also known as noble or rare gases. The inert gases are six in numbers. They are,

Write a short note on Chemical Kinetics.

         Chemical kinetics : The branch of physical chemistry which deals with the study of the speed or rate of chemical reactions and also the explanation of their mechanism is called chemical kinetics.

What do you mean by conjugate acid-base pair ?

           Conjugate acid-base : The base formed by the donation of a single proton by an acid is called the conjugate base of the acid. Similarly, the acid formed by the acceptation of a single proton by a base is called the conjugate acid of the base.

What are the differences between order and molecularity ?

What your love means to me....

Yes, Yes I am emotional...and I need emotions...I am hunting for emotions.....emotions are my power..emotions are my weakness.....emotions are my inspirations...emotions are all I have...emotions are my solutions...emotions make me questioned.....emotions are what I can share....emotions are what I want to be shared with me by you and only you....

I don't wanna see STARS......

MARTVIEW...it may that u guys r known with this software previously but I WASN'T... I found it yesterday and downloaded it. Its a kind of reader of the specific format .mart. You can convert documents like .pdf to .mart using this software also. Specialty of this software is the way you will read the document is different, like you r flipping the pages with your mouse. The interface is excellent. With this software you can download .mart documents from a huge collection.

An awesome, Completely Free Download Manager, "Mipony Download Manger". Make it yours today..

Internet Download Manager is mostly preferred for Downloading from Internet, but its not free. Today I will tell you about a Download Manager which is Completely Free with some Awesome Features. 

~*~*~*~*~*~*~*~*~*~*~ Mipony Download Manager ~*~*~*~*~*~*~*~*~*~*~

How to download videos from youtube.com? Complete Solution to download videos from youtube.com and almost all other online video stores in HD Quality*

This awesome free-of-cost software downloads video from youtube.com and almost all other web sites with online video in High Definition (HD) quality [If available]. You can download videos from YouTube, Metacafe, Dailymotion, Megavideo, blogs with videos, newspapers, television websites, etc…

Society, Education, System and WE !!!

Well, the question which is hunting me deep inside for the last 5-7 days, Why I will have to care about others a lot? Why I will have to care about what my father wants me to do, to be? I have my own life, my own choices, then why before taking decisions which are fully related to me, I will have to consider my parents opinions?

Decisions like, side of education, the way of learning, the way of living are all related to me only. What do you think? Should my parents get their hands in it? I don't think so. I should be doing what suits me most. At least when I am a mature person to handle these cases of my life.

Blogspot Tutorial : 4 Easy Steps to Create and Start blogging freely at Blogspot.com or Blogger

Well, This is the first tutorial where we will be creating our blog and will publish one blog post on our free blogspot blog. So lets start..

First of all I would like to say something about Blogspot, subdomain of which we will be using in general. You can buy your own domain, perhaps I am assuming for this tutorial that you will be using a subdomain. For example, if you choose “myblog” as the URL of your blog, your address will be www.myblog.blogspot.com

Becoming a good person, a gentle one I got the title "Jerk", at some cases "Jackass"

Nearly 5 years ago I was a completely different person from the type of person I am now. I was that much of rough as much I am gentle now. I was, you know, a bad, hot temper, rude, trouble maker, ……I don’t know much English, that’s why failing to choose the correct words to describe how I was, but I hope you can understand.

But I left that dark path on 29th October 2006 and never did such kind of bad things from then. I changed completely to someone, completely different.

ভালো হয়ে, ভদ্র হয়ে উপাধি পেলাম - ‌'বোকা', ক্ষেত্রবিশেষে 'বলদ'

আমি আজ যেমন, আজ থেকে বছর চারেকের একটু বেশি আগে ছিলাম ঠিক এর উল্টো। আজ যতটা ভদ্র থাকি আগে ততটাই অভদ্র ছিলাম। এককথায় খারাপ, রগচটা, বেয়াদব, বদমাইশ, বাটপার টাইপের একটা ছেলে ছিলাম। আরো কিছু বিশেষণ যোগ করা যেতে পারতো। তবে ব্লগে লিখা যাবে কিনা ভেবে লিখলাম না।

কিন্তু ২৯ অক্টোবর, ২০০৬ থেকে সেই যে সবকিছু বাদ দিলাম, আজ পর্যন্ত আর সেপথে হাঁটিনি। পুরোটাই বদলে গেছি আমি। 

Watch 1971 er Muktijuddher Itihas by ATN Bangla : The History of the Independence War of 1971 by ATN Bangla

In this post I offere you to watch some videos which were made by Journalists of different countries. Those videos were collected and recently been released as a documentary titled as "1971 er Muktijuddher Itihash by ATN Bangla" [In English - The history of the Independence War of 1971 by ATN Bangla] by a popular news channel "ATN Bangla" of Bangladesh. The commenrty of this video is in Bangla but there many parts where the presidents and journalists and ministers of different countries will be talking in English. Above all, the missereis you will watch will not require any commentry to understand , What hapened and How Happened?

Bollywood Horror Movie “Haunted”, review and download link

This movie has also been directed by the director of 1920, Vikrom Bhat and nothing else to say about it. An awesome horror movie to watch. Watch it today.

Bollywood Horror Movie “1920”, review and download link

This is the most terrific horror movie I have ever seen in my life. It frightened me that hard that I even forgot to breath. While watching the movie in my room alone with a headphone at midnight, the movie forced me so hard twice to turn on the light and turn off the monitor. However, I don’t know how it will affect you. But surely, you will enjoy it.

How to write good codes or What are the good programming practices to follow !!

The following post highlights some good programming practices what beginner programmer can follow. Applying these increases the readability of codes, will make make codes more easier to update. 

Well, individual programmers should have their own programming styles to maintain, but still there are some practices that the beginners can follow. With times every programmers find out their own styles. Following is a list of things that beginners can do while coding or solving a problem.

টাকা কতো সস্তা !!!

টাকা কতো সস্তা !!!
                          তন্ময় চক্রবর্তী

সন্ধ্যার আঁধারে 

ঘরে আমি বসে যে
ভাবছি রাঁধবো কি
পেটে বড় ক্ষুধা যে

নিজের ঘরের মাঝে
আমি নিজে খুঁজে মরি
জানি চাল নেই তবু
....এই আর কি

How to merge two sorted arrays? Merging Sort Algorithm, Explanations with Animated Presentation, The Program

Merging Sort: 

Merging sort requires two previously sorted array which will be merged into one single array which will be a sorted array. If the source arrays are not sorted then the algorithm won't work. If you need to sort two unsorted arrays then you can place one array after another then operate the new array with any sorting algorithm to sort it. Another important thing is that, the source arrays will have to be there in sorted in the same order, either ascending or descending.

Mafia II : Reviews

I like to play video games. And in this case, Mafia is the ever best game I have played. Its storyline, graphics, characters, views are just so real that it seems like I am not playing a game, I am watching a movie.

Bought Sapphire HD 5450 1GB DDR3 PCIE HDMI to Play Mafia II, Review, Full Specification and Links

Well, I don't know much about graphics cards and its features and facts related to performance. Its the first time I bought any graphics card.

A website has copied my posts

The website, titled as "Priyoboi", has copied all my notes on C Programming from this blog. I permitted everyone announcing that anyone can use my notes, posts and other at wherever they want but just mention my credit. Following this, that above given website has copied my notes and posted at their website and mention the credit as "Credit : Tanmay Chakrabarty". 

They did what they should have done. No complain here. 

But I think they should have provided me some backlinks to my posts. What do you say?

Garbage Collection

Garbage collection. What you get from the title of the topic? Well, while we are coding we use variable or memory location. We may need an array initially for storing some initial elements, then we take more arrays while we are manipulating. At some part of the manipulation, it may that we dont need the initial array anymore. I mean it may that we have already took all the elements of the initial array and processed and stored them in another array for furthur processing and dont need the initial array anymore. However, that initial array still remains eating up some memory locations.

Understanding Variable scope in C++

Understanding Variable scope is very important because it can sometime leads us to unwanted value changing or hazards while coding. Like, we have declared a variable but still its showing error while compiling or running. Look at the following code,

for(int x=0;x<5;x++)    //For Loop 01
   cout<<"Inside For Loop 01";
cout<<x<<" times";    //Line01  

When we will compile this code we get some kind of error msg which may vary from compiler to compiler, but in general the error msg will be related to the variable x.

Allocating and Deallocating memory OR use of New/Delete OR allocating memory in runtime OR declaring array in runtime | in C++

Well, first of all we should be known with Variable Scope, Garbage Collection.

Ok, now. When we declare a variable like as follows,

int a;

it allocates a specific portion of memory for that variable and when we go beyond the scope of the variable the garbage collection system automatically deallocates or in general, deletes the memory location which was occupied by the variable.

But in some cases, like when declaring an array, we might need to allocate a number of array elements which we don’t and which will be specified by the user at the runtime. In such a case we have to declare the array with the number of elements given by the user. Here, we can use the new operator as follows,

Single Layer Perceptron Learning Algorithm and Flowchart of the Program and the Code of the Program in C++

The Single Layer Perceptron Learning Algorithm:

Step 1:        Initialize all weights and threshold and values.
Step 2:        Get the weighted sum of one input.
Step 3:        Compare the weighted sum with the threshold and set value to output.
Step 4:        If the input is of class A

'Smriti Amlan' (Non-erasable Memories), Vodra Mor, Rajshahi City

On the memories of the great liberation war of Bangladesh, this monument 'Smriti Amlan' (Non-erasable Memories) is situated at the Vodra Mor, Rajshahi City, Bangladesh. It was opened on 26th March, 1991 on the Independence Day. Guidance on Architectural Design was provided by Rajiudding Ahmed.

This monument is a symbol of the presence of Bangladesh. There are 3 pillers in the monument. There are 24 steps in each piller which symbolizes the 24 years of  movements and final independence between 1947-1971. 

Approximately 30 Lakh (3 million) people died in the war and this has been symbolized by those 30 wholes on the monument.

Rajshahi City Corporation Building or Rajshahi Nogor Vobon

Isn't its a nice building? This is the City Corporation Building of my city Rajshahi. I like it. On the ground of the old city corporation building a new shopping mall is getting built. This is the new building of about 4-5 years old.

The Speech of J. K. Rowling at Harvard University on June 5, 2008 in Text and Video Format

J. K. Rowling, the famous writer of the book series Hary Potter, which is also featured film in Hollywood gave an very energetic and inspiring speech at Harvard University on June 5, 2008 to the graduate students. The main theme of her speech was to acknowledge the students about the benefits of failure and overcoming the challenges of life with Hope, Determination. Following is the text of the speech she provided from the harvardmagazine.com [Full link given below the post with video links]

Text of the speech of Steve Jobs at Stanford University on June 12, 2005 in Text and Video

I heard about this speech from my mom. It was published in one of the newspapers. Mom read it and after reaching home she told the story of the life of a great inspiring and brave man, Steve Jobs. What to say about him, I think you all know him more than I do. However he had never been graduated, but he was present there at Stanford University and he told three stories. Three stroies from his very own life. He showed, how life's ups and downs are connected, why to keep your faith more stable. 

I am requesting you that you please read the following text of the speech he provided ar Stranford University. I am sure that you will find a lot of very valuable things out of the speech which can even change your life.

Text of the speech of Bill Gates at Harvard University, Video links also.

Bill Gates, one of the most successful person, in the fields of business, engineering, technology, popularity. I respect him a lot. Few days earlier I heard about his speech at Harvar University on June 7, 2007. I searched youtube.com for the video of his speech and searched google for the text of his speech. Found them and thought to post them here.