Scalar expressions in Perl combine data items using operators like arithmetic, string, comparison, and logical operators. Control structures like conditional expressions and loops like while, until, for, and foreach allow repetition and flow control. Blocks enclosed in curly braces group statements. The if-else, if-elsif conditional expressions and statements execute blocks of code conditionally. Looping constructs iterate until a condition is met or a fixed number of times. Loop refinements like last, next, and redo control flow within loops.
Computer Network notes (handwritten) UNIT 1NANDINI SHARMA
Introduction of computer network, layered architecture, topology, guided and unguided media, signals, multiplexing, OSI vs TCP/IP , IP address, TCP , UDP, DHCP, DNS, HTTP, etc.
It is common to base a firewall on a stand - alone machine running a common Os, Firewall functionality can also be implemented as a software module in a router or LAN switch.
Computer Network notes (handwritten) UNIT 1NANDINI SHARMA
Introduction of computer network, layered architecture, topology, guided and unguided media, signals, multiplexing, OSI vs TCP/IP , IP address, TCP , UDP, DHCP, DNS, HTTP, etc.
It is common to base a firewall on a stand - alone machine running a common Os, Firewall functionality can also be implemented as a software module in a router or LAN switch.
These pages will show how to process PHP forms with security in mind. Proper validation of form data is important to protect your form from hackers and spammers!
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
2. SCALAR EXPRESSIONS
Scalar data items are combined into expressions using operators.
$c=12;
$d=3+($c);
1) ARITHMETIC OPERATORS
Perl provides usual arithmetic operator including auto-increment and auto-decrement.
Operator Example Result Definition
+ 7 + 7 = 14 Addition
- 7 - 7 = 0 Subtraction
* 7 * 7 = 49 Multiplication
/ 7 / 7 = 1 Division
** 7 ** 7 = 823543 Exponents
% 7 % 7 = 0 Modulus
$c=17;
$d=++$c; //increment then assign
$c=12;
$d=$c ++; //assign then increment
Binary arithmetic operation:
$a+=3;
$a=a+3;
3. 2)String Operators
In Perl most of the processing is done by using built-in functions
and regular expressions.
Perl uses period (.) for concatenation of strings
The other string operator is (x), used to replicate strings.
$a=“hello” x 3
$a=“hellohellohello”
$foo.= “ ”
Arithmetic Operators used in String Context.
1. Auto-increment
This operator can be applied to a variable.
If a variable is assigned with string of letters and digits then auto
increment operation is applied on the string from rightmost character.
eg: $a=‘all12’;
print ++$a;
result: bmm23
2. Unary minus
If this is applied to string which starts with a plus or minus character,
then it returns the same string with opposite sign.
eg. $name=“sia”
-$name=“-sia”
4. 3) Comparison operator
Values of comparison is returned in numbers.
1--- if true and (“ ”) – if false
These are classified into two kinds. One for numbers and other for strings.
Numbers: ==,!=,<,>,<=,>=,<=>(comparison operator)
Strings: eq,ne,lt,gt,le,ge,cmp
4)Logical operator
not ---- !
and ---- &&
or ---- ||
print “OKn” if $a<10 and $b<12;
5) Conditional expressions
it is the one whose value is chosen from one of the alternatives at runtime
depending on the outcome of test.
test? True_exp:false_exp
eg: $a=($a<0)?0:$a;
5. CONTROL STRUCTURES
A control structure is a block of programming that analyzes variables and chooses a
direction in which to go based on given parameters. The term flow control details the
direction the program takes (which way program control "flows").
Blocks: It is a sequence of one or more statements enclosed in curly braces.
eg: {
$positive=1;
$negative=-1;
}
Conditions: They make use of relational operators. It is a Perl expression which is
evaluated in Boolean context.
If it evaluates to --- 0 or (“ “) --- condition is false, else it is treated as true.
$total > 50 and $total <100
A condition can be negated using ! Operator, we can specify that as
!($total > 50 and $total<100)
6. CONDITIONAL EXPRESSIONS
Conditional Expressions should be in brackets.
If-then-else statement:
if($total> 0){
print “$totaln”
} else {
print “wrong total ! n”
}
If-elsif statement
if($total> 70) { $grade=“A”;} elsif($total > 56){ $grade =“B”;} else
{$grade=“C”); }
Alternative to if-then-else statements are ‘conditional expression’ and using ‘or’
operator.
In perl a single statement can be followed by a conditional modifier.
print “OKn” if $volts>=1.5;
7. REPETITION
Testing loops and counting loops can be used for repetition mechanisms.
Testing loops: while($a!=$b){
if($a > $b){
$a=$a-$b;
}else {
$b=$b-$a;
}
}
An until loop statement in Perl programming language repeatedly executes a target
statement as long as a given condition is false.
Syntax
The syntax of an until loop in Perl programming language is −
until(condition) { statement(s); }
Here statement(s) may be a single statement or a block of statements.
The condition may be any expression. The loop iterates until the condition becomes
true.
When the condition becomes true, the program control passes to the line immediately
following the loop.
$a+=2 while $a < $b; (and) $a+=2 until $a < $b;
Although condition is specified after the written statement, it is evaluated before the
statement executed.
8. Do loop:
It is built-in function rather than a syntactic construct.Overhere the condition is tested after
the execution of the block, so the block is executed at least once.
do{
...
}while $a!=$b;
Counting Loops: They use same syntax as c
for($i=1;$i<=10;$i++){
$i_square=$i*$i;
$i_cube=$i**3;
print “ $it$i_squaret$i_cuben”;
}
foreach $i (1..10) {
$i_square=$i*$i; $i_cube=$i**3;
print “ $it$i_squaret$i_cuben”; }
9. LOOP REFINEMENTS
Perl provides three loop commands : last , next and redo . The last and next
command are similar to break and continue statements in c language.
last breaks out of the loop and next forces the next iteration of a loop.
Ex: to terminate input processing if a line contains ‘quit’ is read we write
while <STDIN> {
last if /quit/;
...
}
The redo command repeats the current iteration from the beginning.
Output:
3 4 5 6 7