Finding r's complement and (r-1)'s complement of a number (1s complement and 2s complement)

Finding the r's and (r-1)'s complement Here we are going to learn how to convert a number to its r's and (r-1)'s complement.  Method: Let 'N' is a number and r is its base where r>1 and in N,  'n' is the number of digits before its decimal point then  we can write  r's complement of number = r^n-N EX.                        N = (23)10                               here r = 10                               n = 2 and N = 23  hence we can write the 10's complement of this number as 10^2 - 23 = 77. hence we can say that 10's comp of 23 is 77.  Although...

Read more »

The Tower of Hanoi (interesting fact)

THE Tower Of Hanoi According to legend, there is a set of 64 gold disks on 3 diamond needles, called the Tower of Brahma. Legend reports that the Universe will end when the task is completed. (Edouard Lucas, R ́cr ́ations e e Math ́matiques, Vol. 3, pp 55–59, Gauthier-Villars,eParis, 1893.) How many moves will it need? If done correctly, T (64) = 2^64 − 1 = 1.84 × 10^19 moves. At one move per second, that’s = 1.84 × 10^19 seconds = 3.07 × 10^17 minutes = 5.12 × 10^15 hours = 2.14 × 10^14 days = 5.85 × 10^11 years Current age of Universe is ≈ 10^10 years   ...

Read more »

Process Synchronisastion

Process Synchronization Introduction: In operating system if two or more co-operating processes some logical space i.e both data and code section or only data using some message call. In the process of sharing if two processes starts manipulating the same data at the same time then data inconsistency may occur, hence we need some rules by which we can restrict two or more process to manipulate data at the same time, so that data consistency is maintained. we can view this problem from this example. Let two process P1 and P2 is working on the same resource(data)  a=30(initially).      P1                                          P2  temp...

Read more »

Digital Logic gates (AND gate, OR gate, NOT gate)

Digital Logic Gates Logic gates are the fundamental building blocks of digital systems. There are three basic gates 1.  AND 2.  OR 3.  NOT here in this picture you can find that for AND gates out-put becomes 0 if any of the input is Zero(0). similarly for OR gate out-put is 1 if any of the input is 1. NOT gate simply reverse the input at its out-put. Here we are not going to the details of hardware realization of logic gates.(Since it is not in the syllabus of gate exam.) Although we can realize any circuit using AOI(AND, OR, NOT) gates, there are also two different gates which can also realize any circuit using these gates. So we call these gates as universal gates. Name of these gates are NAND and...

Read more »

Digital Electronics and Gates(And gate, OR gate, Not gate)

Digital Electronics Introduction: When we listen the term digital logic the first thing which comes in our mind is digital values i.e 0 and 1. In digital electronics generation of zero volt input is almost impossible to achieve hence we think values of  ~ 0.5, 0.6, 0.7 V~ as 0V input and  ~ 4.5, 4.6, 4.7V ~ as 5V. So here question is that why we use digital signal if they are actually not discrete, ( as we know we take ~ 0.5, 0.6, 0.7 V~ as 0V input and  ~ 4.5, 4.6, 4.7V ~ as 5V. etc...) So lets starts with some different concepts. Let us take an analog signal Analog to Digital we will quantize this signal using some discrete quantum values, and the portion which comes in between...

Read more »

GATE 2012 Application Form

GATE 2012 Application Form Pre-final year students are not eligible to write GATE 2012. For more details, please refer to eligibility criteria for GATE examination. Hello everyone, date of application form for GATE 2012 has been declared and it stars from 12 september 2012. This time there is a little change in eligibility criteria (you can check it here). You can get application form for GATE from here . From here you can apply for GATE online. You can also view the respective Zones. GATE is conducted through the constitution of eight zones. The zones and the corresponding administrative institutes are: Zone Website IISc Bangaloregate.iisc.ernet.in IIT Bombaywww.iitb.ac.in/gate IIT Delhiwww.iitd.ac.in/gate IIT Guwahatiwww.iitg.ernet.in/gate IIT...

Read more »

GATE Eligibility Criteria for 2012

...

Read more »

Process Scheduling

Process Scheduling In a single processor system where there are many processor fighting for their execution or in the multiprocessor system where the same fight occurs, we need some mechanism or some rules to allocate the CPU one by one to them, and in such a system we need that the CPU of the system must be used efficiently, and this mechanism is known as Process Scheduling. Suppose in a situation where one process starts I/O, then in case of without scheduling the processor will sit idle and hence it decreases the CPU utilization. When a process is waiting in the ready queue and if CPU becomes idle then the operating system selects one of   the process in the ready queue using Short term Scheduler and here is the work of Process Scheduling comes. There are two types of process...

Read more »

Inter-process communication (IPC)

            Inter process Communication If there are two processes executing parallel in an operating system then they may have two types 1. Independent process: Those process who do not affect or affected by another process which is executing in the OS(Operating System).  2. Co-operating Process: These processes need some communication between them to complete their work. Since there are lots of processes who communicates with another process due to several reasons like Information sharing, To increase the computation speed. etc.. Co-operating process needs some mechanism which may allow them to make communication with other processes and this mechanism is known as Inter Process Communication(IPC).  Inter Process Communication is of two types 1....

Read more »

Thread in Operating System

Thre...

Read more »

Process in Operating System

                PROCE...

Read more »

Evolution of Operating System

Now in these days we are working with Operating System like Win7, Vista, Xp, Mac, these are highly graphical and very fast Operating Systems. There are other OS Android, Symbian etc for mobile phone these are also very advanced.       Initially users( basically the scientist or programmer) use batch system, then after Multitasking, Real time system, Multi-programming system, Time sharing system has came...

Read more »