Data Communication and Networking Fundamentals
Fundamentals of Data Communication
Data communication is the exchange of data between devices through a transmission medium.
5 Core Components
- Sender
- Message
- Transmission medium
- Receiver
- Protocol
Effective Communication Requirements
- Delivery: Correct destination
- Accuracy: No errors
- Timeliness: On time
Telecommunication is communication over long distances. Data communication refers specifically to digital data exchange.
Transmission Media
Guided (Wired)
- Twisted pair: Cheap, short distance, more noise
- Coaxial: Better
Additive Manufacturing Processes and Data Formats Explained
Laser Engineered Net Shaping (LENS)
Laser Engineered Net Shaping (LENS) is a powder-based Additive Manufacturing process used for direct metal deposition. It operates using a high-power laser and metal powder feed system. In this process, a focused laser beam creates a molten pool on a metallic substrate. Simultaneously, metal powder is delivered through a nozzle into the melt pool. The injected powder melts instantly and solidifies upon cooling, forming a metallurgically bonded layer. The deposition
Read MoreEssential Java Design Patterns Implementation
Composite Pattern
interface AComponent { int size(); }
public class File implements AComponent { private String name; private int size; public File(String name, int size) { super(); this.name = name; this.size = size; } public int size() { return size; } }
public class Directory implements AComponent { private List<AComponent> children; public Directory(String name) { children = new LinkedList<>(); } public int size() { int result = 0; for (AComponent child : children) result = result +
Read MoreJava Singly Linked List Implementation
A Singly Linked List is a fundamental data structure consisting of nodes where each node contains data and a reference to the next node.
Defining the Node Class
The Node class is the building block of the list, containing the data and the pointer to the next element.
class Node {
private String data;
private Node next;
public Node(String data) {
this.data = data;
}
public void setData(String data) {
this.data = data;
}
public void setNext(Node node) {
Recommendation Systems, Similarity Metrics & Graph Algorithms
Design Recommendation System — Collaborative Filtering
124. Design recommendation system using collaborative filtering (movie streaming) (10 marks — 10 points)
Input: users, movies, ratings → construct utility matrix.
Step 1: Compute similarity between users (user-based) or movies (item-based).
Step 2: Identify nearest neighbors using cosine or Pearson similarity.
Step 3: Predict ratings for unseen movies via a weighted average of neighbors’ ratings.
Step 4: Recommend top-N movies with the highest
Java Architecture: MVC, JDBC, RMI, and SQL Essentials
MVC Design Pattern
MVC is a design pattern that divides an application into three interconnected components to separate concerns, improve maintainability, and support scalable development.
Components of MVC
- 1. Model: Represents business logic and data. It performs calculations, validations, and database operations. It is independent of the UI. Example: A Java class handling data.
- 2. View: Represents the user interface (UI). It displays data from the Model and contains no business logic. Example: Swing