Found 1263 Articles for Computers

Let us learn the concepts of Fastag and Near Field Communication (NFC).Fast TagFASTag is an electronic scanner system used for toll collection in India, which is operated by the National Highway Authority of India.It incorporates the Radio Frequency Identification (RFID) technology for doing toll payments either prepaid or from savings accounts which are linked to it or directly toll owner.The RFID enabled sticker which is fixed to a vehicle’s windshield, and a reader at the toll booth are used to scan this card and wirelessly and automatically processes the payment.When we pass a FASTag-enabled toll plaza, we don’t need to ... Read More

Let us understand the concepts of QR Code and Fastag.QR CodesQR code is called as "Quick Response" and it allows us to encode or store over 4500 characters in a two-dimensional bar code. These codes are the "square barcodes" that are initially developed and used in Japan.The main aim of the QR code is to store the information in such a way that the machine (scanner) can be able to read the data present in the code.Given below is the Sample QR code image −As we can see above all QR codes are made of black dots and white spaces ... Read More

Let us understand the concepts of Bar code and Fastag.Bar CodeA bar code reader decodes the data contained in the barcode and sends it to the computer. It produces a beam of light or a laser beam to read barcodes which is reflected by the bar code image.A light sensitive detector which is present in the reader identifies the bar code by recognizing special bars on both ends of image. With the help of these special bar's reader is able to identify whether the bar code has been read right side up or upside down.Once a barcode is identified by ... Read More

To send the data from one device to another device there should be a connection. The connection can be established to transfer data between the devices can be done in two ways and they are as follows −Connection-Oriented ServiceConnectionless ServicesNow let us discuss the Connection less services.Connection less ServicesIn connectionless the data is transferred in one direction from source to destination without checking that destination is still there or not or if it is prepared to accept the message. Authentication is not needed in this. Example of Connectionless service is UDP (User Datagram Protocol) protocol.Connectionless service is a service that ... Read More

We can define an address mode as the way in which the memory address of an operand is specified in a computer instruction. Address modes specify how the location of an operand in memory is represented in an instruction. Operations are performed with the help of some data and the data is stored in a computer memory or registers. On the basis of that, there are two types of addressing modes namely, memory address mode and register address mode. The most basic difference between the two is that in the memory address mode, the address of the operand is present ... Read More

Linear Bounded Automaton (LBA) is a restricted form of Turing Machine in which input tape is finite.ExampleProve that LBA ⊂ PSPACEPSPACE is a superset of the set of context-sensitive languages.Now to prove LBA=PSPACE, We use theorem of Space compression with tape reduction which states that, For every k-tape S(n) space-bounded off-line Turing Machine M and constant c>0, there exists a one-tape cS(n) space-bounded off-line turing machine N such that L(M)=L(N).Following identity holds for −DSPACE(S(n))=DSPACE(O(S(n)))and NSPACE(S(n))=NSPACE(O(S(n)))Since LBA is one-tape n space-bounded Turing Machine it follows −LBA=NSPACE(n)---------------------(1)Now by Savitch theorem, if S is fully space constructible and S(n)>log(n) thenNSPACE(S(n)) ⊆DSPACE(S^{2}(n)) -------------(2)Final proofLBA=NSPACE(n)............by(1)⊆DSPACE(n^{2})............by(2)⊂DSPACE(n^{3})............by ... Read More

Push down Automata (PDA) is complement of the PDA that contain Substring bbbStepsMake the PDA for accepting those strings that have conation bbb.Complement it by making non-accepting as accepting and vice versa.Construct PDAYou can construct the PDA as shown below for the (a, b)* languageThe nature of transition format is Input, Top of stack, PUSH/POPExamplea ,a , aa means on i/p a and top of stack is a then push aAt q0 i, e initial if a or b anything came move state to q1Till q1 we get 1 b to make substring b_ _ so now on q1 if ... Read More

Let us begin by understanding the concept of deterministic finite automata (DFA) in the theory of computation (TOC).Deterministic Finite Automaton (DFA)In DFA, for each info image, one can decide the state to which the machine will move. Henceforth, it is called Deterministic Automaton.Formal Definition − A Deterministic Finite automata is a 5-tuplesM=(Q, ∑, δ, q0, F)Where, Q − Finite set called states.∑ − Finite set called alphabets.δ − Q × ∑ → Q is the transition function.q0 ∈ − Q is the start or initial state.F − final or accept state.Non-deterministic finite automata (NDFA)In NDFA, for a specific info image, ... Read More

A Turing machine (TM) is a 7-tuple (Q, ∑, Γ, δ, q0, qaccept , qreject).Where, Q is a finite set of states.∑ is the input alphabet that does not contain the blank symbol t.Γ is the tape alphabet, where t ∈ Γ and ∑ ⊆ Γ.δ: (Q × Γ) → (Q × Γ × {L, R}) is the transition function.q0 ∈ Q is the start state.qaccept ∈ Q is the accept state.qreject ∈ Q is the reject state, where qreject ≠ qaccept.For accepting even-length palindrome over the alphabet {0, 1}, follow the steps given below −Match the first and last ... Read More

ProblemDesign a TM (Turing Machine) that takes a binary number as an input and replaces the last digit of the string with its Boolean complement.SolutionA Turing machine is a 7-tuple (Q, ∑, Γ, δ, q0, qaccept , qreject)Where, Q is a finite set of states.∑ is the input alphabet that does not contain the blank symbol t.Γ is the tape alphabet, where t ∈ Γ and ∑ ⊆ Γ.δ − (Q × Γ) → (Q × Γ × {L, R}) is the transition function.q0 ∈ Q is the start state.qaccept ∈ Q is the accept state.qreject ∈ Q is the ... Read More