Lec16 Intro to Computer Engineering by Hsien-Hsin Sean Lee Georgia Tech -- Fi...Hsien-Hsin Sean Lee, Ph.D.
This document discusses finite state machines (FSMs) including Mealy and Moore machines. It provides examples of state diagrams for Mealy and Moore machines and describes how to design the logic circuits for an FSM from its state table. Key steps include generating Boolean functions for outputs and next states, simplifying the functions, and creating logic gates for the outputs, next state logic, and current state registers. An example of a vending machine FSM is also presented with its state diagram and logic circuit design.
This document discusses color representation in App Inventor. It contains the following key points:
1. Colors in App Inventor are represented using the #AARRGGBB format, with values between 0-255 for alpha, red, green, and blue components.
2. It demonstrates how to convert between hexadecimal, decimal, and RGB component representations of colors.
3. It shows an example of calculating the signed long integer that corresponds to a given color in #AARRGGBB format.
This document summarizes various attacks on the RSA cryptosystem over 30 years, including:
- When p=q, the private key can be derived from the public key
- Using twin primes p and p+2 to factor the modulus
- Hastad's broadcast attack to derive the plaintext from encryptions using the same message but different public keys
- Wiener's attack and Boneh-Durfee's attack to derive the private key d when it is below a certain threshold based on the modulus n
- Common modulus attacks when encryptions use the same modulus n but different public exponents e
- Issues that can arise from reusing the prime factors p and q in different keys
There are 6 apples on a tree. 2 fall off, leaving 4 apples remaining.
At a party, 57 balloons fly down. 19 of them burst, leaving 38 balloons remaining.
The shopkeeper has 32 Easter eggs. He sells 17 eggs, leaving 15 eggs remaining.
This document discusses various datapath subsystems including shifters and multipliers. It describes barrel shifters and logarithmic shifters, noting that barrel shifters have O(N^2) transistors while logarithmic shifters have O(NlogN) transistors. For multipliers, it explains how a basic array multiplier works by forming partial products and summing them, and notes the critical paths involve the full adders in the top row. It also introduces carry save multipliers for faster multiplication.
Comparison Of Dengue Cases Between Chosen District In Selangor By Using Fouri...Mohd Paub
compare dengue cases in shah alam, gombak and klang which recorded highest dengue cases every year by refer to trend, harmonic function and graph plotted on Maple.
This document discusses synchronization in distributed systems and various algorithms for achieving mutual exclusion. It covers centralized, distributed, and token ring algorithms for mutual exclusion. The centralized algorithm uses a coordinator but has a single point of failure. Distributed algorithms overcome this but require more messages. The token ring algorithm passes a token between processes but can lose the token if a process crashes. In comparing the algorithms, the document examines their message requirements, delay before entry, and potential problems.
The document discusses algorithms for solving the mutual exclusion problem in multithreaded programs. It begins by describing two inadequate algorithms for two threads that fail to guarantee deadlock freedom. It then presents Peterson's algorithm and Kessels' single-writer algorithm, proving they satisfy mutual exclusion, deadlock freedom, and starvation freedom for two threads. The document also discusses using tournament algorithms and the filter algorithm to generalize two-thread solutions to work for multiple threads by having threads progress through levels like a tournament bracket.
Lec16 Intro to Computer Engineering by Hsien-Hsin Sean Lee Georgia Tech -- Fi...Hsien-Hsin Sean Lee, Ph.D.
This document discusses finite state machines (FSMs) including Mealy and Moore machines. It provides examples of state diagrams for Mealy and Moore machines and describes how to design the logic circuits for an FSM from its state table. Key steps include generating Boolean functions for outputs and next states, simplifying the functions, and creating logic gates for the outputs, next state logic, and current state registers. An example of a vending machine FSM is also presented with its state diagram and logic circuit design.
This document discusses color representation in App Inventor. It contains the following key points:
1. Colors in App Inventor are represented using the #AARRGGBB format, with values between 0-255 for alpha, red, green, and blue components.
2. It demonstrates how to convert between hexadecimal, decimal, and RGB component representations of colors.
3. It shows an example of calculating the signed long integer that corresponds to a given color in #AARRGGBB format.
This document summarizes various attacks on the RSA cryptosystem over 30 years, including:
- When p=q, the private key can be derived from the public key
- Using twin primes p and p+2 to factor the modulus
- Hastad's broadcast attack to derive the plaintext from encryptions using the same message but different public keys
- Wiener's attack and Boneh-Durfee's attack to derive the private key d when it is below a certain threshold based on the modulus n
- Common modulus attacks when encryptions use the same modulus n but different public exponents e
- Issues that can arise from reusing the prime factors p and q in different keys
There are 6 apples on a tree. 2 fall off, leaving 4 apples remaining.
At a party, 57 balloons fly down. 19 of them burst, leaving 38 balloons remaining.
The shopkeeper has 32 Easter eggs. He sells 17 eggs, leaving 15 eggs remaining.
This document discusses various datapath subsystems including shifters and multipliers. It describes barrel shifters and logarithmic shifters, noting that barrel shifters have O(N^2) transistors while logarithmic shifters have O(NlogN) transistors. For multipliers, it explains how a basic array multiplier works by forming partial products and summing them, and notes the critical paths involve the full adders in the top row. It also introduces carry save multipliers for faster multiplication.
Comparison Of Dengue Cases Between Chosen District In Selangor By Using Fouri...Mohd Paub
compare dengue cases in shah alam, gombak and klang which recorded highest dengue cases every year by refer to trend, harmonic function and graph plotted on Maple.
This document discusses synchronization in distributed systems and various algorithms for achieving mutual exclusion. It covers centralized, distributed, and token ring algorithms for mutual exclusion. The centralized algorithm uses a coordinator but has a single point of failure. Distributed algorithms overcome this but require more messages. The token ring algorithm passes a token between processes but can lose the token if a process crashes. In comparing the algorithms, the document examines their message requirements, delay before entry, and potential problems.
The document discusses algorithms for solving the mutual exclusion problem in multithreaded programs. It begins by describing two inadequate algorithms for two threads that fail to guarantee deadlock freedom. It then presents Peterson's algorithm and Kessels' single-writer algorithm, proving they satisfy mutual exclusion, deadlock freedom, and starvation freedom for two threads. The document also discusses using tournament algorithms and the filter algorithm to generalize two-thread solutions to work for multiple threads by having threads progress through levels like a tournament bracket.
The document discusses various algorithms for achieving distributed mutual exclusion and process synchronization in distributed systems. It covers centralized, token ring, Ricart-Agrawala, Lamport, and decentralized algorithms. It also discusses election algorithms for selecting a coordinator process, including the Bully algorithm. The key techniques discussed are using logical clocks, message passing, and quorums to achieve mutual exclusion without a single point of failure.
This document provides information about a 7-day faculty development training program on distributed systems to be held from November 30th to December 6th 2015 at University College of Engineering, Pattukottai. The training is sponsored by Anna University and has a maximum capacity of 25 participants. Selected faculty members from AICTE approved colleges affiliated with Anna University can attend for free. Topics to be covered include foundations of distributed systems, peer to peer services, process and resource management, and research issues.
Multiprocessing -Interprocessing communication and process sunchronization,se...Neena R Krishna
This document discusses interprocessor communication and process synchronization. It describes how independent processes can cooperate by exchanging data through interprocessor communication methods like shared memory and message passing. It also explains process synchronization techniques like semaphores, locks, and barriers that allow processes to coordinate access to shared resources and prevent race conditions. The key synchronization methods of semaphores, locks, and barriers are defined and semaphore implementation using wait and signal operations is demonstrated using the classic producer-consumer problem example.
This paper summarizes and improves upon the NTBCBT mutual exclusion algorithm. The NTBCBT algorithm has problems related to safety, liveness, and scheduling when nodes request access to a critical resource. The paper proposes an improved algorithm called PBCBT that addresses these weaknesses. PBCBT requires only 3log(N) messages per access to the critical section, compared to 4log(N) for NTBCBT. It also has an improved synchronization delay of 2log(N) messages compared to 3log(N) for NTBCBT. The improvements are achieved through removing unnecessary messages, reorganizing node instructions, and prioritizing requests based on timestamps.
Mutual Exclusion in Wireless Sensor and Actor NetworksZhenyun Zhuang
This document discusses mutual exclusion in wireless sensor and actor networks. It begins by introducing wireless sensor networks and how they have evolved into wireless sensor and actor networks which can both sense and act on their environments. This introduces new challenges around resource utilization that must be addressed. Specifically, the document identifies the problem of mutual exclusion - ensuring only a minimum necessary subset of actors take action for a given event to avoid issues like inefficient resource usage. It defines different types of mutual exclusion and proposes both a greedy centralized approach and a distributed localized approach to address this problem efficiently while meeting application-specific delay bounds and fully covering the event region.
This lecture discusses concurrency and synchronization in operating systems. It introduces principles of concurrency and challenges such as sharing global resources. Mutual exclusion techniques like semaphores and monitors are presented to help manage concurrent access. The document also discusses interleaving and overlapping of processes on uni-processors and multi-processors. A simple example of an echo program is used to illustrate potential issues with determinism and reproducibility when processes run concurrently.
The document discusses principles of concurrency in operating systems, including mutual exclusion and synchronization. It covers various techniques for managing concurrent processes such as hardware support using interrupt disabling or compare-and-swap instructions. It also covers higher-level synchronization methods like semaphores, monitors, and message passing. It provides examples of how these techniques can solve concurrency issues like the bounded buffer problem and readers-writers problem.
A New Function-based Framework for Classification and Evaluation of Mutual Ex...CSCJournals
This paper presents a new function-based framework for mutual exclusion algorithms in distributed systems. In the traditional classification mutual exclusion algorithms were divided in to two groups: Token-based and Permission-based. Recently, some new algorithms are proposed in order to increase fault tolerance, minimize message complexity and decrease synchronization delay. Although the studies in this field up to now can compare and evaluate the algorithms, this paper takes a step further and proposes a new function-based framework as a brief introduction to the algorithms in the four groups as follows: Token-based, Permission-based, Hybrid and K-mutual exclusion. In addition, because of being dispersal and obscure performance criteria, introduces four parameters which can be used to compare various distributed mutual exclusion algorithms such as message complexity, synchronization delay, decision theory and nodes configuration. Hope the proposed framework provides a suitable context for technical and clear evaluation of existing and future methods.
Multiprocessors(performance and synchronization issues)Gaurav Dalvi
This document discusses performance and synchronization issues in multiprocessor systems. It describes shared memory architectures like UMA, NUMA and distributed shared memory. It discusses factors that affect cache performance like CPU count, cache size and block size. It also discusses synchronization mechanisms like locks, flags and barriers that are used to synchronize access to shared resources. Different hardware primitives for synchronization are described, including atomic exchange, test-and-set, and load-linked/store-conditional instructions.
This document discusses interprocess communication and synchronization. It describes race conditions that can occur when multiple processes access shared data concurrently. It introduces the concept of critical sections and mutual exclusion to prevent race conditions. Solutions to achieve mutual exclusion include semaphores and monitors. Semaphores use wait and signal operations while monitors provide mutual exclusion through language-level constructs. Condition variables allow processes to wait for and signal specific events within monitors.
Semaphore is an Indian software development and business process outsourcing company established in 1994. It provides a range of services including software development, application maintenance, testing, and business process outsourcing. Semaphore has development centers in India and the US, and aims to be a reliable outsourcing partner through ISO and CMMI certifications, a global delivery model, and an emphasis on people, processes, and technology.
Mutual Exclusion using Peterson's AlgorithmSouvik Roy
This document discusses mutual exclusion algorithms for ensuring processes can access shared resources safely. It introduces the critical section problem and requirements for a solution. Centralized and decentralized mutual exclusion approaches are described. Popular algorithms are compared, including Dekker's, Lamport's bakery, and Peterson's algorithms. The document outlines how these algorithms work and their limitations. It proposes improvements using time-stamped and lock-based approaches and discusses future work applying these algorithms in distributed systems.
UNIT I INTRODUCTION 7
Examples of Distributed Systems–Trends in Distributed Systems – Focus on resource sharing – Challenges. Case study: World Wide Web.
This document discusses synchronization and semaphores. It begins by explaining how mutual exclusion can be achieved in uni-processors using interrupt disabling, but this does not work in multi-processors. Semaphores provide a solution using atomic test-and-set instructions. Semaphores allow processes to suspend execution and wait for signals. They avoid busy waiting by putting processes to sleep when the semaphore value is not positive. The document provides examples of using binary and general semaphores for problems like mutual exclusion and process synchronization.
The document discusses several algorithms for process synchronization and mutual exclusion in distributed systems:
- Token ring algorithm passes an exclusive token around a logical ring of processes to control access to shared resources.
- Ricart-Agrawala algorithm uses message ordering and timestamps to elect a process to enter the critical section.
- Lamport's mutual exclusion algorithm uses request queues and timestamps to ensure only one process is in the critical section at a time.
- Election algorithms like the Bully and Ring algorithms elect a coordinator process to handle synchronization and recovery from failures.
1) A semaphore consists of a counter, a waiting list, and wait() and signal() methods. Wait() decrements the counter and blocks if it becomes negative, while signal() increments the counter and resumes a blocked process if the counter becomes positive.
2) The dining philosophers problem is solved using semaphores to lock access to shared chopsticks, with one philosopher designated as a "weirdo" to avoid deadlock by acquiring locks in a different order.
3) The producer-consumer problem uses three semaphores - one to limit buffer size, one for empty slots, and one for locks - to coordinate producers adding to a bounded buffer
OS Process Synchronization, semaphore and Monitorssgpraju
The document summarizes key concepts in process synchronization and concurrency control, including:
1) Process synchronization techniques like semaphores, monitors, and atomic transactions that ensure orderly access to shared resources. Semaphores use wait() and signal() operations while monitors provide mutual exclusion through condition variables.
2) Concurrency control algorithms like locking and two-phase locking that ensure serializability of concurrent transactions accessing a database. Locking associates locks with data items to control concurrent access.
3) Challenges in concurrency control like deadlocks, priority inversion, and starvation that synchronization mechanisms aim to prevent. Log-based recovery with write-ahead logging and checkpoints is used to ensure atomicity of transactions in
Temple of Asclepius in Thrace. Excavation resultsKrassimira Luka
The temple and the sanctuary around were dedicated to Asklepios Zmidrenus. This name has been known since 1875 when an inscription dedicated to him was discovered in Rome. The inscription is dated in 227 AD and was left by soldiers originating from the city of Philippopolis (modern Plovdiv).
The document discusses various algorithms for achieving distributed mutual exclusion and process synchronization in distributed systems. It covers centralized, token ring, Ricart-Agrawala, Lamport, and decentralized algorithms. It also discusses election algorithms for selecting a coordinator process, including the Bully algorithm. The key techniques discussed are using logical clocks, message passing, and quorums to achieve mutual exclusion without a single point of failure.
This document provides information about a 7-day faculty development training program on distributed systems to be held from November 30th to December 6th 2015 at University College of Engineering, Pattukottai. The training is sponsored by Anna University and has a maximum capacity of 25 participants. Selected faculty members from AICTE approved colleges affiliated with Anna University can attend for free. Topics to be covered include foundations of distributed systems, peer to peer services, process and resource management, and research issues.
Multiprocessing -Interprocessing communication and process sunchronization,se...Neena R Krishna
This document discusses interprocessor communication and process synchronization. It describes how independent processes can cooperate by exchanging data through interprocessor communication methods like shared memory and message passing. It also explains process synchronization techniques like semaphores, locks, and barriers that allow processes to coordinate access to shared resources and prevent race conditions. The key synchronization methods of semaphores, locks, and barriers are defined and semaphore implementation using wait and signal operations is demonstrated using the classic producer-consumer problem example.
This paper summarizes and improves upon the NTBCBT mutual exclusion algorithm. The NTBCBT algorithm has problems related to safety, liveness, and scheduling when nodes request access to a critical resource. The paper proposes an improved algorithm called PBCBT that addresses these weaknesses. PBCBT requires only 3log(N) messages per access to the critical section, compared to 4log(N) for NTBCBT. It also has an improved synchronization delay of 2log(N) messages compared to 3log(N) for NTBCBT. The improvements are achieved through removing unnecessary messages, reorganizing node instructions, and prioritizing requests based on timestamps.
Mutual Exclusion in Wireless Sensor and Actor NetworksZhenyun Zhuang
This document discusses mutual exclusion in wireless sensor and actor networks. It begins by introducing wireless sensor networks and how they have evolved into wireless sensor and actor networks which can both sense and act on their environments. This introduces new challenges around resource utilization that must be addressed. Specifically, the document identifies the problem of mutual exclusion - ensuring only a minimum necessary subset of actors take action for a given event to avoid issues like inefficient resource usage. It defines different types of mutual exclusion and proposes both a greedy centralized approach and a distributed localized approach to address this problem efficiently while meeting application-specific delay bounds and fully covering the event region.
This lecture discusses concurrency and synchronization in operating systems. It introduces principles of concurrency and challenges such as sharing global resources. Mutual exclusion techniques like semaphores and monitors are presented to help manage concurrent access. The document also discusses interleaving and overlapping of processes on uni-processors and multi-processors. A simple example of an echo program is used to illustrate potential issues with determinism and reproducibility when processes run concurrently.
The document discusses principles of concurrency in operating systems, including mutual exclusion and synchronization. It covers various techniques for managing concurrent processes such as hardware support using interrupt disabling or compare-and-swap instructions. It also covers higher-level synchronization methods like semaphores, monitors, and message passing. It provides examples of how these techniques can solve concurrency issues like the bounded buffer problem and readers-writers problem.
A New Function-based Framework for Classification and Evaluation of Mutual Ex...CSCJournals
This paper presents a new function-based framework for mutual exclusion algorithms in distributed systems. In the traditional classification mutual exclusion algorithms were divided in to two groups: Token-based and Permission-based. Recently, some new algorithms are proposed in order to increase fault tolerance, minimize message complexity and decrease synchronization delay. Although the studies in this field up to now can compare and evaluate the algorithms, this paper takes a step further and proposes a new function-based framework as a brief introduction to the algorithms in the four groups as follows: Token-based, Permission-based, Hybrid and K-mutual exclusion. In addition, because of being dispersal and obscure performance criteria, introduces four parameters which can be used to compare various distributed mutual exclusion algorithms such as message complexity, synchronization delay, decision theory and nodes configuration. Hope the proposed framework provides a suitable context for technical and clear evaluation of existing and future methods.
Multiprocessors(performance and synchronization issues)Gaurav Dalvi
This document discusses performance and synchronization issues in multiprocessor systems. It describes shared memory architectures like UMA, NUMA and distributed shared memory. It discusses factors that affect cache performance like CPU count, cache size and block size. It also discusses synchronization mechanisms like locks, flags and barriers that are used to synchronize access to shared resources. Different hardware primitives for synchronization are described, including atomic exchange, test-and-set, and load-linked/store-conditional instructions.
This document discusses interprocess communication and synchronization. It describes race conditions that can occur when multiple processes access shared data concurrently. It introduces the concept of critical sections and mutual exclusion to prevent race conditions. Solutions to achieve mutual exclusion include semaphores and monitors. Semaphores use wait and signal operations while monitors provide mutual exclusion through language-level constructs. Condition variables allow processes to wait for and signal specific events within monitors.
Semaphore is an Indian software development and business process outsourcing company established in 1994. It provides a range of services including software development, application maintenance, testing, and business process outsourcing. Semaphore has development centers in India and the US, and aims to be a reliable outsourcing partner through ISO and CMMI certifications, a global delivery model, and an emphasis on people, processes, and technology.
Mutual Exclusion using Peterson's AlgorithmSouvik Roy
This document discusses mutual exclusion algorithms for ensuring processes can access shared resources safely. It introduces the critical section problem and requirements for a solution. Centralized and decentralized mutual exclusion approaches are described. Popular algorithms are compared, including Dekker's, Lamport's bakery, and Peterson's algorithms. The document outlines how these algorithms work and their limitations. It proposes improvements using time-stamped and lock-based approaches and discusses future work applying these algorithms in distributed systems.
UNIT I INTRODUCTION 7
Examples of Distributed Systems–Trends in Distributed Systems – Focus on resource sharing – Challenges. Case study: World Wide Web.
This document discusses synchronization and semaphores. It begins by explaining how mutual exclusion can be achieved in uni-processors using interrupt disabling, but this does not work in multi-processors. Semaphores provide a solution using atomic test-and-set instructions. Semaphores allow processes to suspend execution and wait for signals. They avoid busy waiting by putting processes to sleep when the semaphore value is not positive. The document provides examples of using binary and general semaphores for problems like mutual exclusion and process synchronization.
The document discusses several algorithms for process synchronization and mutual exclusion in distributed systems:
- Token ring algorithm passes an exclusive token around a logical ring of processes to control access to shared resources.
- Ricart-Agrawala algorithm uses message ordering and timestamps to elect a process to enter the critical section.
- Lamport's mutual exclusion algorithm uses request queues and timestamps to ensure only one process is in the critical section at a time.
- Election algorithms like the Bully and Ring algorithms elect a coordinator process to handle synchronization and recovery from failures.
1) A semaphore consists of a counter, a waiting list, and wait() and signal() methods. Wait() decrements the counter and blocks if it becomes negative, while signal() increments the counter and resumes a blocked process if the counter becomes positive.
2) The dining philosophers problem is solved using semaphores to lock access to shared chopsticks, with one philosopher designated as a "weirdo" to avoid deadlock by acquiring locks in a different order.
3) The producer-consumer problem uses three semaphores - one to limit buffer size, one for empty slots, and one for locks - to coordinate producers adding to a bounded buffer
OS Process Synchronization, semaphore and Monitorssgpraju
The document summarizes key concepts in process synchronization and concurrency control, including:
1) Process synchronization techniques like semaphores, monitors, and atomic transactions that ensure orderly access to shared resources. Semaphores use wait() and signal() operations while monitors provide mutual exclusion through condition variables.
2) Concurrency control algorithms like locking and two-phase locking that ensure serializability of concurrent transactions accessing a database. Locking associates locks with data items to control concurrent access.
3) Challenges in concurrency control like deadlocks, priority inversion, and starvation that synchronization mechanisms aim to prevent. Log-based recovery with write-ahead logging and checkpoints is used to ensure atomicity of transactions in
Temple of Asclepius in Thrace. Excavation resultsKrassimira Luka
The temple and the sanctuary around were dedicated to Asklepios Zmidrenus. This name has been known since 1875 when an inscription dedicated to him was discovered in Rome. The inscription is dated in 227 AD and was left by soldiers originating from the city of Philippopolis (modern Plovdiv).
How to Download & Install Module From the Odoo App Store in Odoo 17Celine George
Custom modules offer the flexibility to extend Odoo's capabilities, address unique requirements, and optimize workflows to align seamlessly with your organization's processes. By leveraging custom modules, businesses can unlock greater efficiency, productivity, and innovation, empowering them to stay competitive in today's dynamic market landscape. In this tutorial, we'll guide you step by step on how to easily download and install modules from the Odoo App Store.
Andreas Schleicher presents PISA 2022 Volume III - Creative Thinking - 18 Jun...EduSkills OECD
Andreas Schleicher, Director of Education and Skills at the OECD presents at the launch of PISA 2022 Volume III - Creative Minds, Creative Schools on 18 June 2024.
Level 3 NCEA - NZ: A Nation In the Making 1872 - 1900 SML.pptHenry Hollis
The History of NZ 1870-1900.
Making of a Nation.
From the NZ Wars to Liberals,
Richard Seddon, George Grey,
Social Laboratory, New Zealand,
Confiscations, Kotahitanga, Kingitanga, Parliament, Suffrage, Repudiation, Economic Change, Agriculture, Gold Mining, Timber, Flax, Sheep, Dairying,
A Visual Guide to 1 Samuel | A Tale of Two HeartsSteve Thomason
These slides walk through the story of 1 Samuel. Samuel is the last judge of Israel. The people reject God and want a king. Saul is anointed as the first king, but he is not a good king. David, the shepherd boy is anointed and Saul is envious of him. David shows honor while Saul continues to self destruct.
19. producer: consumer:
while (true) while (true)
{ {
/* produce item v */ while (in <= out)
b[in] = v; /* do nothing */;
in++
} w = b[out];
out = (out + 1);
/* consume item w */
}
19