The Dining Philosopher Problem – The Dining Philosopher Problem states that K philosophers seated around a circular table with one chopstick between each pair of philosophers. There is one chopstick between each philosopher. A philosopher may eat if he can pick up the two chopsticks adjacent to him.
A presentation on the Dining Philosopher's Problem, explaining the problem, issues while solving the problem and solutions to the problem. The presentation then takes the user through the Requirement Engineering for the problem via its 4 phases, including, Requirement Discovery, Analysis, Validation and Management. The presentation also includes Use Case Diagrams and Data Flow Diagrams.
The Dining Philosopher Problem – The Dining Philosopher Problem states that K philosophers seated around a circular table with one chopstick between each pair of philosophers. There is one chopstick between each philosopher. A philosopher may eat if he can pick up the two chopsticks adjacent to him.
A presentation on the Dining Philosopher's Problem, explaining the problem, issues while solving the problem and solutions to the problem. The presentation then takes the user through the Requirement Engineering for the problem via its 4 phases, including, Requirement Discovery, Analysis, Validation and Management. The presentation also includes Use Case Diagrams and Data Flow Diagrams.
Operating system 24 mutex locks and semaphoresVaibhav Khanna
Mutual Exclusion - If process Pi is executing in its critical section, then no other processes can be executing in their critical sections
2. Progress - If no process is executing in its critical section and there exist some processes that wish to enter their critical section, then the selection of the processes that will enter the critical section next cannot be postponed indefinitely
3. Bounded Waiting - A bound must exist on the number of times that other processes are allowed to enter their critical sections after a process has made a request to enter its critical section and before that request is granted
Assume that each process executes at a nonzero speed
No assumption concerning relative speed of the n processes
A brief introduction to Process synchronization in Operating Systems with classical examples and solutions using semaphores. A good starting tutorial for beginners.
Maximum CPU utilization obtained with multiprogramming
CPU–I/O Burst Cycle – Process execution consists of a cycle of CPU execution and I/O wait
CPU burst followed by I/O burst
CPU burst distribution is of main concern
Mission ,Vision statement, and strategies of UNICEF
Strategic Plan ,Mission Statement,vision,and Goal of UNICEF
Resource Partners, Sponsorship
UNICEF World Warehouse, UNICEF Research Center, UNICEF High Level structure
Recruitment & Selection Process of UNICEF
UNICEF’S STRENGTHS AND WEAKNESSES
Operating system 24 mutex locks and semaphoresVaibhav Khanna
Mutual Exclusion - If process Pi is executing in its critical section, then no other processes can be executing in their critical sections
2. Progress - If no process is executing in its critical section and there exist some processes that wish to enter their critical section, then the selection of the processes that will enter the critical section next cannot be postponed indefinitely
3. Bounded Waiting - A bound must exist on the number of times that other processes are allowed to enter their critical sections after a process has made a request to enter its critical section and before that request is granted
Assume that each process executes at a nonzero speed
No assumption concerning relative speed of the n processes
A brief introduction to Process synchronization in Operating Systems with classical examples and solutions using semaphores. A good starting tutorial for beginners.
Maximum CPU utilization obtained with multiprogramming
CPU–I/O Burst Cycle – Process execution consists of a cycle of CPU execution and I/O wait
CPU burst followed by I/O burst
CPU burst distribution is of main concern
Mission ,Vision statement, and strategies of UNICEF
Strategic Plan ,Mission Statement,vision,and Goal of UNICEF
Resource Partners, Sponsorship
UNICEF World Warehouse, UNICEF Research Center, UNICEF High Level structure
Recruitment & Selection Process of UNICEF
UNICEF’S STRENGTHS AND WEAKNESSES
Interfacing With High Level Programming Language
High Level Programming Language
Categories of programming languages
Processing a High-Level Language Program
Advantages of high-level languages
Interface-Based Programming
Interfaces in Object Oriented Programming Languages
Implementing an Interface
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.
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.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
For more technical information, visit our website https://intellaparts.com
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
We have compiled the most important slides from each speaker's presentation. This year’s compilation, available for free, captures the key insights and contributions shared during the DfMAy 2024 conference.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
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.
2. Group members:
ROLL NO:
ROLL NO:
ROLL NO:
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ROLL NO:
Group No 02
University of Azad Jammu & Kashmir
Neelum Campus
BSCS V Semester, 2014-18
Operating System
Topic: Dining Philosophers
Presented By:
Mansoor Bashir
4. Dining Philosophers Problem
Five philosophers who spend their lives
just thinking and eating.
Only five chopsticks are available to the
philosophers
5. Dining Philosophers Problem
Each philosopher thinks. When he
becomes hungry, he sits down and
picks up the two chopsticks that are
closest to him and eats.
After a philosopher finishes eating, he
puts down the chopsticks and starts to
think.
9. Possibility of Deadlock
If all philosophers become
hungry at the same time and
pick up their left chopstick, a
deadlock occurs.
10. 17 December 2018
Possible Solutions
Allow at most four philosophers
to be sitting simultaneously at
the table.
Allow a philosopher to pick up
his/her chopsticks only if both
chopsticks are available (to do
this she must pick them up in a
critical section)
11. 17 December 2018
Possible Solutions
Use an asymmetric solution; that is,
an odd philosopher picks up first
her left chopstick, whereas an even
philosopher picks up her right
chopstick and then her left
chopstick.
12. 17 December 2018
Possibility of
Starvation
Two philosophers who are fast
eaters and fast thinkers, and
lock the chopsticks before
others every time.
13. 17 December 2018
Critical Regions
A critical region is a section of
code that is always executed
under mutual exclusion.
14. 17 December 2018
Critical Regions
They consist of two parts:
1.Variables that must be
accessed under mutual
exclusion.
2.A new language statement
that identifies a critical region
in which the variables are
accessed.
16. Types of Semaphores
Counting semaphore – integer value
can range over an unrestricted integer
domain.
Binary semaphore – integer value
cannot be > 1; can be simpler to
implement.
17. Implementing a Counting Semaphore
Data structures
binary-semaphore S1, S2;
int C;
Initialization
S1 = 1
S2 = 0
C = initial value of semaphore S
18. wait(S1);
C--;
if (C < 0) {
signal(S1);
wait(S2);
}
signal(S1);
Implementing a Counting Semaphore
wait(S):
19. wait(S1);
C++;
if (C <= 0)
signal(S2);
else
signal(S1);
Implementing a Counting Semaphore
signal(S):
21. Two goals to achieve in solving the problem:
Deadlock free -- if at any time there is a hungry
philosopher, then eventually some philosopher will
eat.
Lockout free -- every hungry philosopher eventually
gets to eat.
The configuration of philosophers and sticks for the
case of n = 5 is illustrated below:
22. 1. Deterministic algorithms:
As is proven in D. Lehman and M. O. Rabin's paper in
1981, no fully distributed and symmetric deterministic
algorithm for dining philosophers is possible. We can
prove it using the following example by introducing the
role of an adversary.
There can be an evil adversary, who contrives to
produce deadlock. For example, the adversary can
come up with the following "clever" strategy:
All n philosophers become hungry at the same
moment
23. They each pick up their left fork simultaneously
because of the symmetry and the fact that each philosopher's
behavior is strictly deterministic, they have no choice but to put
down their sticks and try again later still precisely at the same
time.
By repeating this cycle constantly, the adversary will be able to
bring deadlock into this problem, thus makes any deterministic
algorithms fail to work.
Continue….
25. Fork Available[i] is a Boolean variable for each Pi - Pi+1 pair,
which indicates whether the fork between them is available.
The subtractions and additions are to be interpreted modulo n
We toss a coin when the hungry philosopher decides whether
to pick up the left fork or the right one first.
This randomization prevents any evil adversary's scheme. We
can show that the algorithm is deadlock free.
Continue….
26. The proof is based on that the coin tosses made by
philosophers are independent random events. Thus,
even if the adversary scheduler tries to bring on
deadlock, a combination of tosses will finally arise that
enables some philosopher to obtain two sticks. As the
index number (0,1,...i) attached to a philosopher is for
naming only, the algorithm is totally symmetric.
Continue….
27. However, this algorithm is not lockout free. There can
exist a very greedy philosopher Pi, and he tries to
prevent his neighbor from eating by always beating him
in the race of picking up the stick. Therefore, we need
some more parameters to improve this algorithm. We
can add two variables for each pair of philosophers, one
lets Pi to inform Pi+1 of his desire to eat, and vice versa.
The other shows which of the two eats last. In this way,
we can achieve both the deadlock free and lockout free
Continue….
28. 17 December 2018
Monitor
Dining Philosophers Example
monitor dp
{
enum {thinking, hungry, eating} state[5];
condition self[5];
void pickup(int i) // Following slides
void putdown(int i) // Following slides
void test(int i) // Following slides
void init() {
for (int i = 0; i < 5; i++)
state[i] = thinking;
}
}
29. 17 December 2018
Dining Philosophers
void pickup(int i) {
state[i] = hungry;
test(i);
if (state[i] != eating)
self[i].wait();
}
30. 17 December 2018
void putdown(int i) {
state[i] = thinking;
// test left and right
// neighbors
test((i+4) % 5);
test((i+1) % 5);
}
Dining Philosophers