Understanding Distributed Systems: Concepts, Challenges, and Solutions
1. Defining Distributed Systems and Their Consequences
A Distributed System is a collection of independent computers that appear to users as a single coherent system. These computers communicate and coordinate their actions by passing messages to achieve a common goal.
Significant Consequences of Distributed Systems:
- Concurrency: Distributed systems allow multiple components to run concurrently, enabling parallel execution of tasks.
- Consequence: Increased performance and scalability but also challenges
Node.js & Express.js: Modules, Routing, REST APIs, and JSON
Node.js Modules
Modules in Node.js are reusable code blocks that organize functionality into smaller, manageable files. Each module can export functions, objects, or values for other files to import and use.
Types of Modules
- Core Modules: Built into Node.js, requiring no installation.
- Local Modules: Created by developers for specific tasks.
- Third-Party Modules: Installed using npm (Node Package Manager).
Core Modules
Core modules provide essential functionalities like file handling, HTTP requests, and
Read MoreHTML5 and PHP: Syntax, Semantics, and Superglobal Variables
HTML: Markup to differentiate information about content. W3C recommendations for contents and elements. XHTML requires empty elements terminated by a trailing slash. In HTML5, the trailing slash in empty elements is optional. Semantic advantages include maintainability, performance, accessibility, and Search Engine Optimization. HTML5 does not require the use of the <html>, <head>, and <body> tags.
PHP
PHP code is enclosed within <?php ?> tags.
Comments:
#/* *///
Variables:
Variables
Read MoreMicroprocessors, Assemblers, and Computer Architecture
Microprocessors: The Core of Computing
A microprocessor, the brain of a computer, is an integrated circuit containing arithmetic, logic, control, and I/O functions on a single chip.
Key Aspects of Microprocessors
Definition
A microprocessor is a programmable logic device that reads, processes, and executes binary instructions from memory. It performs calculations and makes decisions based on received data.
Architecture
- CISC (Complex Instruction Set Computing): Large instruction set for complex tasks with
Operating System Fundamentals: Definitions, Types, and Functions
Operating System Definition
An operating system (OS) is a suite of software designed to allow communication between a computer user and the hardware, managing the computer’s resources in a comfortable and efficient manner.
What is a transmission medium?
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What is POST?
POST stands for Power-On Self-Test. It is a diagnostic testing sequence that a computer’s basic input/output system (BIOS) runs to determine if the computer keyboard, random access memory, disk
Read MoreEnsemble Methods: Bagging and Stacking in Machine Learning
Automated Feature Selection
Backward Feature Elimination
This process begins with a model containing all features. After training and testing, the least significant variable is removed. Backward feature elimination is implemented in scikit-learn using Recursive Feature Elimination (RFE).
Code Example for RFE:
from sklearn.feature_selection import RFE
X = df.copy() # Create separate copy
del X['Divorce'] # Delete target variable
y = df['Divorce']
# Create the model object
model = LogisticRegression(