Define embedded system and what are itsmain charactristics

Answers

Answer 1

Answer:

Embedded system is defined as, it is the combination of between hardware and software which performed various specific tasks. It is a dedicated functions which contain large electrical and mechanical components. Basically it is the real time computing constraint.

Example: Printers, washing machine and automobiles.

Characteristics of embedded system are:

It is performed single function and specific operations. It is based on microprocessor and micro controller.Software are used for flexibility and good features and hardware are used for the security purpose and better performance.


Related Questions

What is computer virus?

Answers

It is a (software) program that is installed on a computer without the user's knowledge for the purpose of making harmful changes. A computer virus attaches itself to another program (the execution of the host program triggers the action of the virus). And most of them perform actions that are malicious in nature, such as destroying data. A computer virus operates in two ways: As soon as it lands on a new computer, begins to replicate or it plays dead until the trigger kick starts the malicious code. The term 'computer virus' was formally defined by Fred Cohen in 1983.

Answer:

A computer virus is a virus attached onto your computer, and it gives you bugs and can often delete your important files.

Differentiate between the DFS and BFS algorithms for graphtraversal.

Answers

Answer:

DFS Algorithm stands for Depth First Search.

BFS Algorithm stands for Breadth First Search.

Explanation:

DFS stands for Depth First Search. In DFS, starting from the root node all the elements are scanned following one of the branches of the tree till it finds the desired element, if it hits the leaf node then the nearest ancestor is searched and son on.

BFS Algorithm stands for Breadth First Search. In BFS algorithm, starting from the root node all the vertices at the next level are scanned from left to right. That means, starting from the root node, all the level 1 nodes are searched from left to right and then all the level 2 nodes are searched and so on till the finding the desired node.

Both DFS and BFS are advantageous in their own way. However, the memory required for BFS is high when compared to DFS. This is because BFS has to keep track of the pointers of child nodes. If the element that we are searching lies at the end of the graph DFS is faster. If the element that we are searching lies at the top of the graph BFS is faster.

A ____ resembles a circle of computers that communicate with each other.
Answer
hierarchical network
star network
bus network
ring network

Answers

Answer:

ring network

Explanation:

In a ring network, the nodes are arranged in a circular pattern where each node is connected to two adjacent nodes. In this topology, any node can communicate with any other node via the intermediaries.

In comparison,

- in a star network every communication needs to pass through a central hub node

- in a bus, each node is connected to a shared linear communication bus.

- in a hierarchical network nodes are organized along a tree structure layout.

A function that is called or summoned into action by its reference in another function is a ____.
A) function prototype
B) called function
C) calling function
D) function declarator

Answers

Answer:

Answer is B. Called function

Explanation:

The function which is called is the called function.

In which function we call it, that's calling function.

You use the ____ data type to hold any single character.

a.
single

b.
char

c.
float

d.
byte

Answers

b. char. Char is short for character.

.When a design begins with a consideration of what the systemmust accomplish, it is called:
A.user-centered design B.data-driven design C.event-driven design D.task-centered design

Answers

Answer: D) Task-centered design

Explanation: Task centered design is the technique for a design to made in such a way that it can have the desired or expected result . The goals are set in it and the task is decided in a particular structure. Thus a design having any such system , it is known as task centered design. It is mainly focused on the user and the way this design can be used by them.

How is the bootstrap program started?

Answers

Answer:

Bootstrapping :- It refers when a process does not require any input from outside to start.

Bootstrap program:- It is the first code that is executed when the computer system is started.

Bootstrap program is a part of ROM and it is non-volatile memory. Then the  operating system is loaded in the RAM by bootstrap program after the start of the computer system. Then the operating system starts the device drivers.

A bootstrap program is the first code that is executed when the computer system is started. ... The operating system is loaded into the RAM by the bootstrap program after the start of the computer system. Then the operating system starts the device drivers.

If the data needs to be processed in a First In First Out (FIFO) manner, we typically use a(n) ____.

A.
stack

B.
queue

C.
map

Answers

Answer:

B. queue

Explanation:

If the data needs to be processed in a First In First Out (FIFO) manner, we typically use a queue.

Convert the following binary numbers to decimal:

10010101
01110110
00110011
11100010
10000001

Answers

Answer:

Hi!

10010101 = 149;

01110110 = 118;

00110011 = 51;

11100010 = 226;

10000001 = 129;

Explanation:

To convert binary numbers you can use this formula:

[tex]N = bit_{1} * 2^{0} + bit_{2} * 2^{1} + bit_{3} * 2^{2} + bit_{4} * 2^{3} + ... + bit_n 2^{n-1}[/tex], where position of the bit₀ is the rightmost digit of the number.

Results, using the formula:

10010101 = 1*2⁰+1*2²+1*2⁴+1*2⁷ = 1 + 4 + 16 + 128 = 149.

01110110 = 1*2¹+1*2²+1*2⁴+1*2⁵+1*2⁶  = 118;

00110011 = 1*2⁰+1*2¹+1*2⁴+1*2⁵ = 51;

11100010 = 1*2¹+1*2⁵+1*2⁶+1*2⁷ = 226;

10000001 = 1*2⁰+1*2⁷ = 129;

Note: All bits in 0 multiplied by any number are 0.

Final answer:

To convert binary numbers to decimal, use the place value system. Multiply each digit by 2 raised to the power of its position and add up the results.

Explanation:

To convert binary numbers to decimal, we use the place value system. Each digit in the binary number represents a power of 2. We start from the rightmost digit and multiply it by 2 raised to the power of its position. Then, we add up all the results to get the decimal equivalent.

For example, for the binary number 10010101:

The rightmost digit is 1, so we multiply it by 2 raised to the power of 0, which is 1.The next digit is 0, so we multiply it by 2 raised to the power of 1, which is 2.We continue this process for all the digits and add up the results: 1 + 0 + 0 + 16 + 4 + 0 + 1 = 22.

So, the decimal equivalent of 10010101 is 22. Following the same steps, you can convert the other binary numbers to decimal.

Building a linked list forward places the new item to be added at the beginning of the linked list.

True

False

Answers

Answer:

False

Explanation:

When a new item is added to a linked list it gets added to the rear end of the list.

For example if my list is as follows:

A->B->C

Now I want to add D, it will get added as follows:

A->B->C->D

Similarly if I add E, the updated list will become:

A->B->C->D->E

____________________deals with syntax and semantics ofinformation exchange.

a. Presentation layer

b. Session layer

c. Application layer

d. Transport layer

Answers

Answer:

The answer is (a).Presentation Layer

Explanation:

This layer is located at the 6th level of the OSI model, responsible for delivering and formatting the information to the upper layer for further processing. This service is needed because different types of computer uses different data representation. The presentation layer handles issues related to data presentation and transport, including encryption,translation and compression.

Write a program that asks the user to enter a number within the range of 1 through 10. Use a switch statement to display the Roman numeral version of that number. Input Validation: Do not accept a number less than 1 or greater than 10. Prompts And Output Labels. Use the following prompt for input: "Enter a number in the range of 1 - 10: ". The output of the program should be just a Roman numeral, such as VII.

Answers

cout<<"Enter a number in the range of 1 - 10 ";

cin>>num;

// check if the input is valid

if(num<0 || num > 10)

cout<<"Invalid Number"

// checking for appropriate output

switch(num){

case 1:

cout<< "|";

case 2:

cout<< "||";

case 3:

cout<< "|||";

case 4:

cout<< "|V";

case 5:

cout<< "V";

case 6:

cout<< "V|";

case 7:

cout<< "V||";

case 8:

cout<< "V|||";

case 9:

cout<< "|X";

case 10:

cout<< "X";

default :

cout<<" Nothing found";

}

Final answer:

The program asks the user to enter a number between 1 and 10 and uses a switch statement to convert it to a Roman numeral, with input validation to ensure the number is within the specified range.

Explanation:

Converting Numbers to Roman Numerals Using a Switch Statement

To write a program that asks for a number in the range of 1 through 10 and converts it to a Roman numeral, we can utilize a switch statement. Here is an example code in a programming language like C++ or Java:

#include <iostream>
using namespace std;
main() {
 int number;
 cout << "Enter a number in the range of 1 - 10: ";
 cin >> number;
 switch(number) {
   case 1: cout << 'I'; break;
   case 2: cout << 'II'; break;
   case 3: cout << 'III'; break;
   case 4: cout << 'IV'; break;
   case 5: cout << 'V'; break;
   case 6: cout << 'VI'; break;
   case 7: cout << 'VII'; break;
   case 8: cout << 'VIII'; break;
   case 9: cout << 'IX'; break;
   case 10: cout << 'X'; break;
   default: cout << "Error: invalid input.";
 }

 return 0;
}
This program will display a Roman numeral corresponding to the number entered by the user, ensuring that input validation is performed and only numbers between 1 and 10 are accepted.

You want a class to have access to members ofanother class in the same package. Which is themost restrictive access that accomplishes thisobjective?
? public

? private

? protected

? transient

? default access

Answers

Answer:

default access

Explanation:

Classes, methods, variables(identifiers*) declared without any access modifier are considered as default and these can be accesed in others clases of same  package.

Identifiers are the name of classes, methods, variables, arrays, enums, etc.

Given a one dimensional array arr, what is the correct way ofgetting the number of elements in arr

?? arr.length

?? arr.length – 1

?? arr.size – 1

?? arr.length()

Answers

Answer:

The answer is option 1 arr.length.

Explanation:

In java arr.length gives the correct number of elements in the array.The length is function is only applicable for arrays.

The length() method is applicable for strings.

arr.length-1 will give 1 element less.

There is no .size for arrays in java.

So we conclude that arr.length is correct way of getting the number of elements in one dimensional array arr.

Answer:

The answer is arr.length.

Explanation:

In java arr. length gives the correct number of elements in the array. The length() method is applicable for strings. arr. length-1 will give 1 element less. There is no . size for arrays in java. So we conclude that arr.

Learn more about the array, refer:

https://brainly.com/question/13971324.

True / False
. Fixed-length instruction architectures do not use memory as efficiently as variable-length architectures.

Answers

Answer:

TRUE. Variable length instruction architectures are better at memory efficiency than fixed length architectures.

Explanation:

Variable length instruction architectures use memory efficiently than fixed length architectures. Fixed length instructions are used in RISC (Reduced Instruction Set Computers) , where as CISC (Complex Instruction Set Computers ) have instructions of variable length. In fixed instruction length architectures if the instruction has shorter length than that of fixed length it requires padding to increase the instruction length to fixed length. This is wastage of memory.

What will the following code display?

int number = 6;
cout << ++number << endl;




1. 0

2. 5

3. 7

4. 6

Answers

Answer:

7

Explanation:

The operator '++number' is called the pre increment operator which is used to increment the value by 1 first and then assign.

for example:

int n = 10;

b = ++n;

here, it increase the value of 10 first then assign to b. hence, b assign the value 11.

similarly, in the question:

int number = 6;

after that, the pre increment operator increase the value by one and then assign to number.

it means number assign the value 7 and finally print the value.

Therefore, the answer is 7.

Is it legal to "use" an unprotected wireless access point that you discover in a public area? Is it ethical to use it? Hypothetically, if you were at an event and your computer detected a wireless network which was not protected and that was not sponsored by the event or its organizers, would you use it? Justify your answer

Answers

Answer:

The legality of use is dependent on the permissions provided by the owner, service provider ad state's laws. It is not ethical to use open wifi not provided or sponsored by event's organizer.

Some of the risk are:

Privacy leak and risk of confidentiality. Wifi data transfer occur using encryption but there are also some devices that can decrypt this data provided the have access the wifi. In open wifi, since everyone has access hence anyone with malicious intents can overlook your activities by decrypting data. This become more dangerous when a person is accessing bank statement or doing transactions on public wifi.

Data mining is becoming increasingly common in both theprivate and public sectors. Discuss

What do you understand by DATA MINING?
Study and discuss where and how DM can beused?

Answers

Answer:

Data Mining is the process of getting important data from the given set of large amount of data based on some attributes and dimensions

Explanation:

Data Mining can be used in all kind of organizations to take some important decisions based on historical data

In Java a final class must be sub-classed before it.
?? True

?? False

Answers

Answer: False

Explanation: In java, whenever a final class is declared it cannot be extended further and also it is not possible for a declared class to be overridden in the sub class. A class can be declared final by using the final keyword. Final class cannot be extended but they can be used to extend the other classes.Therefore the final class cannot be sub classed before it in java.

Decision-making undercertainty is always easy to solve.
True
False

Answers

Answer:

False

Explanation:

Decision making is a complex subjective process which involves analyzing multiple inputs, current state and identifying the most relevant actions to achieve a set of desired objectives.

The process is complicated by factors such as:

- inadequacy or incorrectness of inputs

- unawareness of the current state

- lack of expertise of the decision maker

- multiplicity of potential actions which lead to desired outcomes

- fuzzy end objectives

TRUE/FALSE

The Interrupt Flag (IF) controls the way the CPU responds to all interrupts.

Answers

Answer: True.

Explanation:

The value of the IF is very important to respond to the interrupts in the OS. It is a system flag bit. All the hardware interrupts will be handled if the flag value is set to 1 else all interrupts will be ignored. It takes two values either 1 or 0.

______ organizations have physical and online dimensions

A. clicks and mortar

B. pure-play

C. virtual

D. brick and mortar

Answers

Answer:

Click and Mortar

Explanation:

In the e-commerce world, a click and mortar organization is a type of business model that includes both its operations in the online and offline domains. Clients are able to shop online and at the same time visit the retailer’s store. It is able to offer its clients fast online transactions and face-to-face service.

Further explanation

Electronic Commerce Describes the process of buying, selling, sending, or exchanging products, services, and / or information through computer networks, including the Internet.

Electronic Business refers to a broader definition of the EC, not only buying and selling goods and services, but also serving consumers, collaborating with business partners, conducting e-learning, and conducting electronic transactions in organizations.

3 forms of EC organization:

• Brick-and-Mortar:

Is an organization that does business offline, sells physical products, and also physical agents.

• Virtual (Pure Play):

Is an organization that conducts business activities only online.

• Click-and-Mortar:

Clicks and mortar refers to the use of electronic sales (CLICK) by combining traditional methods of operation (brick and mortar). Cliks and mortar also refers to the development of electronic commerce that is side by side with conventional business operations by utilizing the strengths in each of the complementary and synergistic channels.

Clicks and mortar, companies can successfully develop parallel electronic trade in parallel with brick and mortar. The level of integration between the two channels is manifested in several dimensions: the actual business processes used for company transactions, the company's brand identity, ownership and management in each channel.

Is an organization that carries out several EC activities, but does major business in the physical world.

E-Marketplace is an online marketplace where buyers and sellers meet to exchange goods, services, money, or information.

Learn  More

clicks and mortar : https://brainly.com/question/12914277

Details

Class: college

Subject: computers and technology

Keywords : clicks and mortar, Electronic Commerce, Electronic Business, E-Marketplace

a network on the internet has a subnet mask of 255.255.240.0.what is the maximum number of hosts it can handle?

Answers

Answer:

4094 hosts

Explanation:

In a network,

     Number of hosts is (2^host no -2)

We have subtracted 2 because out of these hosts two are used in broadcasting and other purposes.  

Host number is equal to the 0's in the Subnet mask

                    255.255.240.0

convert this into binary number i.e

   11111111.11111111.11110000.00000000

So,12 0's are there

           Number of valid hosts= 2^12 -2

                                                = 4096-2

                                                =  4094

Write a program that stores the value 16 in the variable length and the value 18 in the variable width. Have your program calculate the value assigned to the variable perimeter using the formula perimeter = 2 * length + 2 * width. Have your program print the value stored in perimeter.

Answers

Answer:

#include<iostream>

using namespace std;

int main()

{

  int length = 16;

   int width = 18;

   int perimeter = (2*length) + (2 * width);

   cout<<"The perimeter is: "<<perimeter<<endl;

}

Explanation:

First include the library iostream in the c++ program for input/output.

then, create the main function and define the variable with given values in the length and width.

After that calculate the perimeter by using the formula.

perimeter = 2*length + 2*width

and finally display the output  on the screen by using the cout instruction.

write a C program the prints out the size of variables with the following C data types- int, long, unsigned, long long, double, float, char, and double

Answers

C program for finding size of different data types

#include <stdio.h>

//driver function

int main()

{

   int a;  //declaring a of type int

   float b; //declaring b of type float

   double c; //declaring c of type double

   char d; //declaring d of type char

   long e; //declaring e of type long

   long long f; //declaring f of type longlong

   unsigned g; //declaring g of type unsigned

   // Sizeof operator is used to evaluate the size of a variable

printf(" int data type contains: %lu bytes\n",sizeof(a));/*Finding size of int */

printf("float data type contains : %lu bytes\n",sizeof(b));/*Finding size of float */

printf("double data type contains: %lu bytes\n",sizeof(c));/*Finding size of double */

printf("char data type contains: %lu byte\n",sizeof(d));/*Finding size of char */

printf("long data type contains: %lu byte\n",sizeof(e));/*Finding size of long*/ printf("longlong data type contains: %lu byte\n",sizeof(f));/*Finding size of longlong */

printf("unsigned data type contains: %lu byte\n",sizeof(g)); /*Finding size of unsigned */

   return 0;

}

Output

int data type contains: 4 bytes

float data type contains : 4 bytes

double data type contains: 8 bytes

char data type contains: 1 byte

long data type contains: 8 byte

longlong data type contains: 8 byte

unsigned data type contains: 4 byte

The process known as AAA (or “triple A”) security involves three components. _____________ means ensuring that an authenticated user is allowed to perform the requested action.

Answers

Answer:

The process known as AAA (or “triple A”) security involves three components. Authorization means ensuring that an authenticated user is allowed to perform the requested action.

The process known as AAA (or “triple A”) security involves three components. Authorization means ensuring that an authenticated user is allowed to perform the requested action.

What is access control?

By validating various login credentials, such as passwords and usernames PINs, biometric scans, and tokens, access control identifies users. A type of credential known as an authentication factor is one that is used to verify, often in conjunction with other factors.

Multifactor Authentication is a technique that needs multiple authentication methods to validate a user's identity is another feature found in many access control systems. The three AAA are authentication, authorization, and accounting.

Therefore, authorization refers to confirming that a user who has been authenticated is permitted to carry out the specified action.

To learn more about authentication, refer to the below link:

https://brainly.com/question/13553677

#SPJ2

Assume that the reference variable r refers to a serializable object. Write code that serializes the object to the file ObjectData.dat.

Answers

Answer:

FileOutputStream out = new FileOutputStream("ObjectData.dat");

ObjectOutputStream ostream = new ObjectOutputStream(out);

ostream.writeObject(r);

Explanation:

For object serialization, we can use the writeObject method of java.io.ObjectOutputStream class.

The complete code fragment is as follows:

import java.io.*;

class Demo{

      public static void main(String args[]){

             try{

                  r = <Reference to Object to be serialized> ;

                 FileOutputStream out = new FileOutputStream("ObjectData.dat");

                 ObjectOutputStream ostream = new ObjectOutputStream(out);

                  ostream.writeObject(r);

                 ostream.close();

            } catch(Exception e){

                   e.printStackTrace();

            }

      }

}

Write the half function. A function call and the functionprototype
are provided.

void half(float *pv);

float value=5.0;

printf("Value before half: %4.1f\n",value); // Prints 5.0

half(&value);

printf("Value after half: %4.1f\n",value); // Prints 2.5

Answers

Answer:

C code for half()

#include<stdio.h>

void half(float *pv);

int main()

{

float value=5.0;  //value is initialized  

printf ("Value before half: %4.1f\n", value); // Prints 5.0

half(&value);  // the function call takes the address of the variable.

printf("Value after half: %4.1f\n", value); // Prints 2.5

}

void half(float *pv) //In function definition pointer pv will hold the address of variable passed.

{

*pv=*pv/2;  //pointer value is accessed through * operator.

}

This method is called call-by-reference method. Here when we call a function, we pass the address of the variable instead of passing the value of the variable. The address of “value” is passed from the “half” function within main(), then in called “half” function we store the address in float pointer ‘pv.’ Now inside the half(),  we can manipulate the value pointed by pointer ‘pv’. That will reflect in the main(). Inside half() we write *pv=*pv/2, which means the value of variable pointed by ‘pv’ will be the half of its value, so after returning from half function value of variable “value” inside main will be 2.5.

Output:

Output is given as image.

What are the differences between responsibility,accountability and liability?

Answers

Answer: Responsibility is the process when one has an authority over another, accountability means to be answerable to the action of the concerned and liability means to be legally responsible for the concerned.

Explanation:

A person who is responsible must be accountable and vice versa. In liability the person responsible must be governed by some documents for legal bindings to be help responsible for someones else action.

If there is no inheritance in Java then this environment may be__________but not ____________.
object oriented, object based
component based , object based
object based ,component based
object based , object oriented

Answers

Answer:

The answer is object based,component based.

Explanation:

If there is no inheritance in Java then the environment may be object based but not component based.

Component based is an approach in programming in which we divide a problem into different parts called components each of having a specific role in the program.

The difference between component based and object based is re-usability and scale. Component based means to emphasize on responsibilities which are mostly independent and may not share or may share common objects with other components.Object based means to emphasize on the integration of objects, where objects are reused over an entire software.That is why the environment may be object based but not component based.

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