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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" »
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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" »

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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" »
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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" »
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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" »

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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" »
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Types of motor

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Video compression is composed of several  basic Processes. The first four are essentially preprocessing steps. Though they are Not considered compression, they can have a dramatic effect on data reduction.

¡Filtering

Images which lack sharp edges are easier to compress than Images which have sharp edges. Thus a preprocessing step in MPEG is to filter The image to reduce the sharp edges (i.E. High frequencies) by filtering.

The number of pixels used in the average is called the number Of taps. MPEG recommends using a seven tap filter.

¡Color space conversion

¡The second preprocessing step is a Conversion from the RGB color scheme of a computer to the YUV color scheme that Television uses. The Y value is termed the luminance and the U & V... Continue reading "Types of motor" »

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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" »

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Detailed Fastening and Window Systems for Stone Wall Cladding

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Fibreboard. 1:50

Dimensiones paneles (general 120x150x0.8). Tornillos a 8cm (menos en la unión dos paneles que es a 4cm) del margen y entre ellos 28 en horizontal y 16 en vertical. Railes de unión de paneles ancho 10 raíl interior de panel ancho 5. General Fastening detail side view. Continuous T 80/100 mm alumninium profile with a thickness of 2mm. Fastened to the L 50/100 spacer (penetra 10cm en muro). Plaster thermal insulation wall plug (penetra 10cm) Ventilated gap 0.8cm thickness board + 19.5cm hasta mortero de limpieza (1cm). 0.8+4+10+5+0.5 General Fastening detail top view. En T tornilllos distribuidos 4+0.8+4. Alu profile (V-profile 0.6mm) para sostener superiormente el panel. Window detail side view. 2layers of mineral wool termal... Continue reading "Detailed Fastening and Window Systems for Stone Wall Cladding" »

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Computer Crime and Software Sabotage: Risks and Prevention

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Computer Crime

Any illegal or unauthorized behavior in connection with computers and computer networks. Examples of computer crime include:

  • Computer sabotage
  • Unauthorized access
  • Computer forgery
  • Damage to computer data or programs
  • Computer fraud
  • Computer espionage
  • Unauthorized use of a computer
  • Unauthorized use of a protected computer program
  • Hacking

Software Sabotage

Viruses and other invaders. Also sabotage of hardware or software. Modern computers saboteurs commonly use software. The name given to the saboteurs destructive programs are: Viruses, Worms and Trojan horses. They mimic the behavior of living organisms.

Trojan Horse

Is a program that performs a useful task while at the same time carrying out some secret destructive act. Software hides an enemy... Continue reading "Computer Crime and Software Sabotage: Risks and Prevention" »

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