Please re-write paragraphs.

-In the following slides I will be discussing the three different methods that are for determining the requirements for gathering information. I will discuss the advantages and disadvantages of each method, along with explaining the Level-0 Data Flow Diagram, the last thing I will be discussing is the method in which I chose for determining the requirements for the student furniture webstore that the Pine Valley Furniture store decided to plan and implement first.

- The above slide has the three different methodologies listed that are used for requirements gathering. They are the traditional, contemporary, and radical methodologies. I am going to discuss what’s involved in each methodology along with what are the advantages and disadvantages of each methodology.

- The traditional method of doing things is the old way of doing things in which many organizations still use today. I think this method should still be used to some extent because I feel you still get good solid information and feedback from your users. In the traditional way the organization can interview people to see what the ”issues and operation of the current system” and the system coming. (Valacich & George, 2020, p. 148) Traditionally you would interview a lot of different people that have different “needs to find synergies and contrasts among system requirements “(Valacich & George, 2020, p. 148) One of my favorite traditional methods are sitting in on workers as during their daily routine and seeing how they perform their daily tasks and what other tools they need to accomplish them. One last traditional method is to go over old “business documents” so that the organization can see “issues, policies, rules, and directions”. The traditional method also has (examples that are solid that show the use of the organizations data and information). The advantages of traditional methodology are you will get more (solid and correct information from your users when you observe them during their daily work tasks, when the documentation and procedures are analyzed they will give information about the organization as well as identifying the current system requirements, it allows the analyst to work with having the procedures and documentation in front of them to refer back to, the documentation will list everyone who is involved in the current system.)The disadvantages of directly observing employees are that it can be (costly and take up too much time, procedures come up missing, users are repeating what’s already been done, the procedures and documents being analyzed may need to be updated along with they may be hard to find, and one last disadvantage is that the documents and procedures may say one thing about operation but the organization operates in an entirely whole different way.

- The contemporary method is similar to the traditional method. In the contemporary method is where “managers, analysts, users, and other members” that are needed are brought together in a JAD which is a Joint Application Design that is an arraigned process where “very intense meetings” take place to identify and go over the “systems requirements.” (Valacich & George, 2020, p. 159-160) The other thing that happens during use of a contemporary method are (prototypes are developed for the system that clearly define the system requirements are understood in solid terms by showing working versions of system features.) (Valacich & George, 2020) The advantages of the contemporary methodology are in using the Joint Application Design it will allow the users to effectively take place in the process, the organization will have a more solid and precise statement of the systems requirements, and everyone will have a better comprehension of the organizations goals.) ("Prezi", 2020). Some other advantages of the contemporary methodology are in using prototyping because this is where at the (beginning stages of the development prototyping lets the identification of the potential risks involved and to rectify the errors, also when the “developers and testers” are making the prototype they can very easily make it to accommodate what the customer wants and needs with being able to make adjustments when necessary, as well as when showing it to the customer this is the perfect way to do so, and when using prototyping the “developers have a great chance of getting much wanted “valuable feedback” from the users so this will save them a great deal of time, effort, and money down the road. According to "Velvetech"(2020), The disadvantages of using the contemporary method are in using the (JAD) Joint Application Design is the more expensive way to go because there are many more people involved and there is not enough resources available.) ("Prezi", 2020). The disadvantages of using prototypes are that “the initial result of a prototype is never the market-ready product”, (making changes all the time will make so there are many designs and changes within the code, and this will slow down the flow in which the employees are doing their tasks), ("Velvetech", 2020) and sometimes “software vendor that covers for the cost of a prototype.” According to "Velvetech"(2020),

1.

(A) A Web server is identified by port number 25 while an email server process using the SMTP protocol is identified by port number 80.

True

False

(b) Both SMTP with HTTP are used to transfer files from one host to another.

True

False

(c) We are sending a 30 Mbit MP3 file from a source host to a destination host. All links in the path between source and destination have a transmission rate of 10 Mbps. Assume that the propagation speed is 2*10⁸ meters/sec, and the distance between source and destination is 10,000 km. Now suppose there is only one link between source and destination. Also suppose that the entire MP3 file is sent as one packet. How many bits will the source have transmitted when the first bit arrives at the destination?

(d) Suppose a client sends an HTTP request message with the "If-modified-since": header. Suppose the object in a server has not changed since the last time a client retrieved the object. Then the server will send a response message with the status code ____.

(e) UDP provides a flow-control service to its applications to eliminate the possibility of the sender overflowing the receiver’s buffer.

True

False

(F)The TCP connection is not an end-to-end TDM or FDM circuit as in a packet-switched network.

True

False

Write a program to multiply a polynomial with a given number.

Code needed in java.

LAUNGEG: C#

Objective:

For this assignment you will be creating two classes, an interface, and a driver program:

• Class Calculator will implement the interface CalcOps
  o As such it will implement hexToDec() - a method to convert from

  Hexadecimal to Decimal.

• Class HexCalc will inherit from Calculator.

• Interface CalcOps will have abstract methods for add( ), subtract( ),

  multiply( ) and divide( ).

• Both classes will implement the CalcOps interface.

o Class Calculator’s add, subtract, multiply and divide will take in 2 integers and return an integer. If you prefer it can take in 2 strings, and return a string.

o Class HexCalc’s add, subtract, multiply and divide will take in 2 strings (hexadecimal numbers) and return a string (hexadecimal number).

This Calculator class will work with whole numbers (int) and hexadecimal (String) values. The hexToDec ( ) method is a helper method included in interface CalcOps, that requires the Calculator class to implement the method which converts hexadecimal numbers to decimal. (Hint: Use language specific utility methods to convert hexadecimal to decimal.)

Submission Guidelines:

Program code – 1 interface program, 2 Classes and a driver program UML diagram - PDF format.

Assignment Requirements:

• Create a parent class calculator that implements the arithmetic operations. You may use input values of integers or Strings.

• Implement method public int hexToDec (String hexValue) which converts hexadecimal numbers to decimal numbers in the parent calculator class.

• Create a class hexCalc which is a child class of the calculator class

o This class performs basic arithmetic operations such as addition,

subtraction, multiplication and division on hexadecimal numbers by

reusing the methods in parent class.
o To do hexadecimal arithmetic, convert the hexadecimal values to

integers, perform the arithmetic operation using the parent class methods

and then convert the result back to hexadecimal string.
o For conversion between hexadecimal and integer values use the

following language specific methods.

C#

Convert.ToString(int,16) Convert integer to hexadecimal

Convert.ToInt32(hex, 16) Convert hexadecmial to integer

• Run the driver program for all calculator operations using decimal and hexadecimal values.

• The biggest challenge you will run into in this assignment will be calling methods with the correct data types as parameters to each method. If you are

getting errors, be sure to double check that what you passed to the method as arguments matches the methods parameter types. Where possible, use your language’s methods to convert to the appropriate type before calling.

• Be sure to convert from integers to strings and vice versa before and after converting from decimal to hex.

Skeleton:

//Design an interface public interface CalcOps

{
// ... includes basic arithmetic operations

 public int hexToDec (String hexToDecimal) ;

}

//Parent class

public class Calculator implements CalcOps

{

}

//Hexadecimal arithmetic calculator that extends calculator

public class HexCalc extends Calculator{

@implement add, subtract, multiply, divide methods

//Reuse parent class methods.

}

public class TestCalculator {

//Provide choice between executing hexadecimal and decimal arithmetic //operations.

// Menu of choices

} // Driver class.

OUTPUT:

Would you like to do calculations with decimal or hexadecimal numbers (1 for Decimal, 2 for Hexadecimal

1

---MENU---
0 - Exit
1 - Addition
2 - Subtraction
3 - Multiplication
4 - Division
Please Choose an Option: 1 Please enter the first number

45

Please enter the second number

67

112 ---MENU---

0 - Exit
1 - Addition
2 - Subtraction
3 - Multiplication
4 - Division
Please Choose an Option: 2 Please enter the first number

34

Please enter the second number

1

33

---MENU---
0 - Exit
1 - Addition
2 - Subtraction
3 - Multiplication
4 - Division
Please Choose an Option: 3 Please enter the first number

23

Please enter the second number

12

276

---MENU---
0 - Exit
1 - Addition
2 - Subtraction
3 - Multiplication
4 - Division
Please Choose an Option: 4 Please enter the first number

10

Please enter the second number

3

3

---MENU---
0 - Exit
1 - Addition
2 - Subtraction
3 - Multiplication 4 - Division

Please Choose an Option: 0
You chose to Exit> THANK YOU !!! HAVE A GREAT DAY!!

Thank you!

In order to borrow an item from the library, a member first enters the membership card into a card reader of the library. The system retrieves the membership details and contacts the university system UniSys to find if the member is an active staff or student. If not, the system does not allow the member to borrow any item from the library and terminates the function. Otherwise, the system asks the member to place the item in the scanner. Once the member does this, the system gets the item details and its type. It also checks if the item is available for loan. The system also finds out the total items already borrowed but not returned. If the item is available for loan, and the total item borrowed but not returned is less than 5, it makes a loan for the member. The item is included in the membership account with the borrowing date and due date for return. The system then increments the total borrowed items by 1, and it makes the item unavailable for other members. The system also decrements the total items reserved of the member if the item was reserved by the member. The member has also choice to request for extended loan time for one more week. If the item was not reserved, one more week is added with the original return date. Finally, it creates a receipt of the loan, and releases the security code of the item. The receipt includes information such as membership number, item call number, loan date, and return date..... in use case diagram

In a few words, explain how a preemptive scheduling policy differs from a non-preemptive scheduling policy.

Using Perl language:
Write a program that reads a string from the standard input, and uses a Perl regular expression to test whether the string looks like a valid credit card number. The card numbers of four major companies follow the following formats:

Visa

13 or 16 digits, starting with 4.

MasterCard

16 digits, starting with 51 through 55.

Discover

16 digits, starting with 6011 or 65.

American Express

15 digits, starting with 34 or 37.

You should test your script with following numbers:

(1)4941 5968 0539 2447

(2) 371642190784801

(3) ‎5168441223630339

(4) 6011988461284820

Please include screenshots for your output.

Write a program to multiply two polynomials.

Code needed in Java.

Give reasons why one might conjecture that the following language is not deterministic.

L = {aⁿb^mc^k: n = m or m = k}.

The following program supposes to calculate the area of a rectangle and square. Then, produce the following output.

Area of Rectangle:
50

Unfortunately, the program has compile-time and run-time errors that prevent the program from running and producing the correct result. Using table 3.1 below, allocate the error(s) on each program line.

1 public class RectangleArea {  
2   Public static void main() {  
3     int width == 10;
4     int height = 5;
5     int recArea = width + height;
6      System.Out.print(Area of Rectangle:);
7      System.out.println(“recArea”)
8     
9

Note:

Some of the answers are given to you as an example.

Table 3.1: compile-time / run-time error

Consider the following java class:

class Student {
   private int student_Number;
   private String student_Name;
   public Student(int stNo,String name) {
        student_Number=stNo;
        student_Name=name;
     }
    public String getName() {
      return student_Name;
    }
     public int getNumber() {
      return student_Number;
     }
    public void setName(String st_name) {
      student_Name = st_name;
    }
}

Write a Tester class named StudentTester which contains the following instruction:

1. Use the contractor to create a student object where student_Number =12567, student_Name = “Ali”.
2. Use the setName method to change the name of the student to “Ahmad”
3. Print the student details(i.e., student’s name and student’s number).

Note:

Include the screenshot of the program output as a part of your answer. Otherwise, you will be marked zero for this question.

What java program would you write to solve the following problems and why does it work? Please also comment on other students’ code at least three times. 1) Implement MyArrayList and MyLinkedList using MyList interface and MyAbstractList as defined in Java Collection Framework. 2) For the following problem use your own created MyArrayList or MyLinkedList if needed. Given an array of words and a width maxWidth, format the text such that each line has exactly maxWidth characters and is fully (left and right) justified. You should pack your words in a greedy approach; that is, pack as many words as you can in each line. Pad extra spaces ' ' when necessary so that each line has exactly maxWidth characters. Extra spaces between words should be distributed as evenly as possible. If the number of spaces on a line do not divide evenly between words, the empty slots on the left will be assigned more spaces than the slots on the right. For the last line of text, it should be left justified and no extra space is inserted between words.

Write a complete program called EvenNums that uses a

method to create arrays of even numbers starting 1 of the given length:

public static int[] getEvenNums(int length) {}

EX:

int[] nums = getEvenNumbers(6);

System.out.println(Arrays.toString(nums));

expected output:

[2, 4, 6, 8, 10, 12]

Matlab

Theoretical Calculations:

t = (-.00025: .00025: 100000);

A1 = 29;

A2 = 1.2*A1;

t1 = (37.2/2)*.00025;

t2 = -(41.3/10)*.00025;

x1 = A1*co(2*pi*(4000)*(t-t1));

x2 = A2*co(2*pi*(4000)*(t-t2));

x3 = x1 + x2;

Remember that the phase of a sinusoid can be calculated after measuring the time location of a positive peak,3 if we know the frequency.

(a) Make measurements of the “time-location of a positive peak” and the amplitude from the plots of x1(t) and x2(t), and write those values for Ai and ti directly on the plots. Then calculate (by hand) the phases of the two signals, x1(t) and x2(t), by converting each time-shift ti to phase. Note: when doing computations, express phase angles in radians, not degrees!

(b) Measure the amplitude and time-shift of x3(t) directly from the plot and then calculate the phase φ3 by hand. In your report, show how the amplitude and time-shift were measured, and how the phase was calculated.

(c) Now use the phasor addition theorem. Carry out a phasor addition of complex amplitudes for x1(t) and x2(t) to determine the complex amplitude for x3(t). Use the complex amplitude for x3(t) to verify that your previous calculations of A3 and φ3 were correct.