Internet Fundamentals: Protocols (TCP/IP, DNS) and Collaboration Tools

Packet Switching Protocol: Understanding TCP/IP

The Internet connects computers around the world regardless of the operating system used and the subnet to which they belong. A common and unique protocol is necessary so that all computers can correctly interpret and understand the information that flows between them.

The TCP/IP Protocol Suite

The TCP/IP is actually a system of protocols, based on dividing the information into packets at the source. These packets are sent through the network, traveling

Read More

Understanding Infectious Diseases: Epidemiology and Drug Resistance

Understanding Infectious Diseases and Public Health

1. Differentiating Epidemic, Endemic, and Pandemic

An epidemic is an outbreak of an infectious disease that spreads quickly, infecting a large number of people within a specific region or population.

If the disease remains consistently present within a determined geographic area or population at predictable rates, it is called endemic.

If the disease infects many countries or continents at the same time, spreading globally, it is called a pandemic.

Read More

Time Series Analysis and Regression Modeling in R

R Setup and Initial Data Handling

Setting the working directory:

setwd("/Users/hajdumarcell/Downloads/Öko. II. R Jegyzet")

Data inspection and preparation:

str(Titanic)
PS4$Date <- as.Date(PS4$Date)

Basic visualization using ggplot2:

ggplot(PS4, aes(x=Date, y=Google_PS4)) + geom_line()

Regression Modeling with Dummy Variables

The general regression model structure, including trend ($t$) and quarterly dummy variables ($DQ$):

$$Y_t = \beta_0 + \beta_1 \times t + \beta_2 \times DQ_1 + \beta_3 \times DQ_

Read More

Spain’s 19th Century Political and Economic Shifts

The Revolutionary Sexenio (1868–1874)

Shortly after the revolution triumphed in 1868, which led to the exile of the monarch, a provisional government was formed. This government promulgated the Constitution of 1869, the most advanced to date, which established a comprehensive bill of rights, including freedom of speech, press, assembly, and association. It also established national sovereignty, the division of powers, universal male suffrage, and the democratic monarchy.

Between 1869 and 1874, two

Read More

The Age of Reason: Social, Scientific, and Economic Change (1660–1785)

The Great Transformation: 1660 to 1785

The period between 1660 and 1785 was a time of amazing expansion for England. The world seemed fundamentally different by 1785. A sense of new, expanding possibilities transformed the daily life of the British people and offered them fresh ways of thinking about their relationship to nature.

There was a sense of relief and escape: relief from the strain of living in a mysterious universe, and escape from the ignorance and barbarism of the Gothic centuries. This

Read More

The American Revolution: Causes, Key Events, and Lasting Impact

The American Revolution was a monumental event in world history that took place between 1775 and 1783, resulting in the thirteen American colonies breaking away from British rule and establishing the United States of America. This revolution was not just a war for independence but a profound transformation in political philosophy, national identity, and global influence.

Historical Background

By the mid-18th century, the British Empire had established firm control over its American colonies. Although

Read More

Java Core Concepts: OOP, Multithreading, and Generics Deep Dive

Core Java Concepts Explained

1. Object-Oriented Programming (OOP) in Java

Java is a fully object-oriented programming language that follows the core principles of Object-Oriented Programming (OOP): encapsulation, inheritance, polymorphism, and abstraction. In Java, everything is treated as an object, which makes it easy to model real-world scenarios.

  • Encapsulation is achieved using access modifiers and getter/setter methods, ensuring that data is protected from unauthorized access.
  • Inheritance allows
Read More

Global Environmental Impacts and Sustainable Solutions

Nuclear Fusion Technology

Nuclear fusion is a process where the fusion (union of atomic cores) releases heat, which is used to vaporize water, moving turbines and generating electric current.

  • Advantages: Necessary raw materials are practically inexhaustible, and the process does not generate radioactive waste.
  • Disadvantages: So far, scientists have not been successful in controlling the nuclear fusion process for sustained energy production.

Human Activities and Planetary Impacts

Human activities result

Read More

Master English: Key Vocabulary and Grammar for Spanish Speakers

Essential English Vocabulary with Spanish Translations

Social and Personal Actions

  • Turning point: (punto de inflexión)
  • Miss out on: (perderse)
  • Milestone: (hito)
  • Hang out: (pasar el rato)
  • Be involved in: (participar en)
  • Run for office: (postularse a un cargo)
  • Overdo: (exagerar)
  • Race: (raza/carrera)
  • Lower: (bajar)
  • Rate: (calificar/tasa)
  • Handle: (manejar)
  • Enable: (habilitar)
  • Make fun of: (burlarse de)
  • Cheer on: (animar)
  • Enforce: (hacer cumplir)
  • Venue: (lugar)
  • Cautious: (cauteloso)
  • Playing a role in: (tener un papel
Read More

Incoterms C Group: CPT, CIP, CFR, and CIF Rules Explained

C Incoterms: Main Information

The ‘C’ group of Incoterms (CPT, CIP, CFR, and CIF) signifies that the seller pays for the main carriage. However, a crucial characteristic of this group is that the transfer of cost and the transfer of risk occur at different locations.

CPT and CIP Incoterms

CPT (Carriage Paid To) and CIP (Carriage and Insurance Paid To) are Incoterms designed for any mode of transportation (multimodal), including air, rail, road, and sea. They are often used for planes, trains, and trucks.

Read More