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Mechanical Gear Systems: Types and Applications

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Gear Mechanisms and Cogwheels Explained

Cogwheels are sets of wheels that have teeth, often called cogs. These teeth fit into the spaces between the teeth of another wheel, allowing one wheel to move the other. They transmit rotary motion between two connected axles, which can be parallel, perpendicular, or oblique. Gears can be cylindrical or conical, and all teeth must be the same shape and size. The two wheels and their corresponding axles rotate in opposite directions.

In this system, N1 and N2 represent the velocities of the corresponding wheels, while Z1 and Z2 are the numbers of teeth. The ratio Z1/Z2 is known as the gear ratio.

Uses:

  • Industrial machinery
  • Vehicles
  • Domestic appliances (e.g., drills, food processors)

Worm Gear Systems: Function

... Continue reading "Mechanical Gear Systems: Types and Applications" »

Stone Materials in Construction: Extraction, Processing & Applications

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Stone Materials in Construction

Stone materials are frequently used in construction due to their strength, durability, and resistance to weathering. Common applications include stone walls, cement pavements, and concrete pillars.

1.1 Extracting and Processing Stone

Stone is extracted from natural deposits. Some types, like marble and granite, exist as large blocks in quarries and require cutting into smaller pieces. Others, such as gravel and sand, are aggregates—fragments or grains of various sizes.

Stone Blocks

Certain stones, like granite and marble, are extracted in large blocks, which are then cut, shaped, and finished.

Quarrying

Large stone blocks are removed from the Earth's crust using methods like controlled explosions, mechanical drilling,... Continue reading "Stone Materials in Construction: Extraction, Processing & Applications" »

Construction & Engineering Terminology: Definitions & Translations

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Construction and Engineering Terminology

Redesign (rediseño): Designing again in order to improve or change a design.

Regulations (Regulaciones): Laws and standards that a design must comply with, for example, safety regulations and quality standards.

Scale (Escala): The ratio between the size of items shown on a drawing and their actual size (in reality).

Schedule (horario): A list of planned activities or things to be done showing the times or dates when.

Set of (conjunto de): Collection/group.

Sketch (Boceto): A rough drawing of initial ideas, also used when production problems require engineers to amend design details and issue them to the workforce immediately.

Slab (Losa): The block of concrete that makes up a floor. It can be laid on the ground... Continue reading "Construction & Engineering Terminology: Definitions & Translations" »

Understanding IoT: Components, Applications, and Future

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What is IoT?

Before 2010, people connected to the internet in what was called the 'Internet of People,' connecting people to apps and to other people.
In IoT 2020, people are connected to the internet, things are connected to the internet, and things are connected to things, connecting things to apps, to other things, and things to people.
IoT is about reusing the Internet Infrastructure and Technologies to connect things.
IoT is the combination of existing technologies + new opportunities + marketing and business.


Embedded Systems

Embedded systems are a combination of hardware and software that complete a specific task. Generally, they are parts of a machine and provide real-time operations with low power consumption, small size, safety, reliability,
... Continue reading "Understanding IoT: Components, Applications, and Future" »

Understanding Electricity and Electronics: DC and AC

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Understanding Electricity and Electronics

Electricity

Matter is formed by atoms consisting of negatively charged particles (electrons) and positively charged particles (protons). Between these particles, there are forces of attraction or repulsion that generate a type of energy called electricity.

In a balanced atom, the number of protons is equal to the number of electrons. The forces of attraction and repulsion between these particles are balanced. When this balance is disturbed, the electrical forces become unbalanced and the electrons are driven by their electrical energy to other atoms in search of new balances.

We call this transfer of charges electrical current, and it is produced in conducting materials.

Conducting materials transmit electrical... Continue reading "Understanding Electricity and Electronics: DC and AC" »

Search Engine Mechanics: Crawling, Indexing, and Ranking

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Search Engine Functions: Crawling, Indexing, Publishing

Crawling

The process by which search engine robots (also known as spiders or web crawlers) discover new and updated web pages and add them to the search engine index. They achieve this by performing an algorithmic scan to determine which pages to crawl, then follow links to interconnect content across the web.

Indexing

Once a document or web page is located, it is processed and stored in a vast database, making it available for user retrieval. Search engines maintain large data centers where their robots process all the pages and information gathered during crawling.

Serving Search Results

The primary goal of search engines is to provide an almost immediate and relevant answer to the user's... Continue reading "Search Engine Mechanics: Crawling, Indexing, and Ranking" »

Understanding Gears: Types, Mechanisms, and Applications

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What are Gears?

Gears are mechanical elements designed to transmit turning movements.

Characteristics of Gears

Two main characteristics define a gear:

  1. Number of Teeth (Z): This characteristic represents the number of teeth on a gear.
  2. Rotational Speed (N): This characteristic represents how fast a gear rotates.

Gear Ratios and Speed Control

Different Number of Teeth

Using gears with different numbers of teeth allows us to modify a machine's rotational speed. If the output gear is larger than the motor gear, it will rotate slower. Conversely, if the output gear is smaller, it will rotate faster.

Same Number of Teeth

If two gears have the same number of teeth, they will rotate at the same speed.

Motor Gear vs. Output Gear

In a gear pair:

  • The motor gear initiates
... Continue reading "Understanding Gears: Types, Mechanisms, and Applications" »

Essential Hand Tools for Electricians and Their Uses

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Pliars: The plier is a hand tool. It is my favorite tool. It is very useful for many kinds of different jobs; for example, it is useful for electricians. It is made of metal, plastic, steel, and other materials. It has a plastic handle, which is insulating. It is used for picking up objects and cutting wire; also, this tool is used for tightening wires. There are many kinds of pliers, like needle nose pliers, clamping pliers, lineman pliers, and side-cutting pliers.

Cutting Tools: It has a special insulating plastic handle and a steel blade. It is made of a lot of different colors. There are many kinds of cutting tools like cutters, electrician scissors, wire strippers, and hacksaws. These tools are very dangerous because they can cut your hands... Continue reading "Essential Hand Tools for Electricians and Their Uses" »

Java List Implementation with Search, Insert, and Remove

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Java List Implementation

Class Definition

public class Lista { 
    private Object[] item;
    private int primeiro, ultimo, pos;

    public Lista(int maxTam) {
        this.item = new Object[maxTam];
        this.pos = -1;
        this.primeiro = 0;
        this.ultimo = this.primeiro;
    }
}

Search Method

public Object pesquisa(Object chave) {
    if (this.vazia() || chave == null) {
        return null;
    }
    for (int p = 0; p < this.ultimo; p++) {
        if (this.item[p].equals(chave)) {
            return this.item[p];
        }
    }
    return null;
}

Insert Method

public void insere(Object x) {
    if (this.ultimo >= this.item.length) {
        throw new Exception("Error: List is full");
    } else {
        this.item[this.ultimo]
... Continue reading "Java List Implementation with Search, Insert, and Remove" »

Primary and Secondary Memory: RAM, ROM, and More

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Primary Memory (Main Memory)

Primary memory holds only the data and instructions on which the computer is currently working. It is generally made up of semiconductor devices. These memories are not as fast as registers. The data and instructions required to be processed reside in the main memory. It is divided into two subcategories: RAM and ROM.

Characteristics of Main Memory:

  • These are semiconductor memories.
  • It is known as the main memory.
  • It is the working memory of the computer.
  • It is faster than secondary memories.
  • A computer cannot run without primary memory.

RAM (Random Access Memory)

RAM (Random Access Memory) is the internal memory of the CPU for storing data, programs, and program results. It is a read/write memory that stores data until... Continue reading "Primary and Secondary Memory: RAM, ROM, and More" »