Notes, summaries, assignments, exams, and problems for Technology

Fundamental Electrical Concepts

Voltage: This is the energy with which a generator is able to push electrons through a circuit (measured in volts).

Intensity (Current): This is the number of electrical charges going through the circuit per unit time (measured in amps).

Resistance: This is the difficulty provided by the material to the passage of electric current (measured in ohms).

Power (Watts): This is the ability of a receiver to perform its function more closely and/or faster (measured in Watts).

Key relationships include:

• $R = V / I$
• $P = V \cdot I$
• $I = V / R$

Circuit Connections

Series Connection

When the elements are connected one after another, the same intensity flows through all components, and the voltage spreads across them.

Parallel Connection

The... Continue reading "Fundamental Electrical Concepts: Voltage, Current, and Resistance" »

Electronic circuits are fundamental systems designed to process information and manage electrical power efficiently.

Structure of Electronic Devices

Electronic devices typically comprise the following functional units:

• Input Devices: Provide the necessary information for the device to function.
• Processing Devices: Control the operation of the device based on the input information.
• Output Devices: Produce end effects, such as visual displays or sound.

These devices commonly include a housing, printed circuit boards (PCBs), and a power supply.

Key Electronic Components

Discrete Components

Discrete components are individual, fundamental units of an electronic circuit. They are categorized into two main types:

• Passive Components: These do not modify the

Fundamentals of Metal Rolling (Laminating)

General Principles of Rolling

Rolling (Laminating) is the process of deforming a metal slab by passing it between two overlapping cylinders rotating in opposite directions. This operation can be performed hot or cold.

Hot Rolling

• It can be considered continuous forging.
• It is performed at temperatures between recrystallization and melting.
• As in forging, the material does not acquire strain hardening (work hardening).

Cold Rolling

• This is done at room temperature.
• Materials acquire strain hardening due to deformation.
• Annealing is required to finish the operation, or even during the process if the deformation is very deep.

Deformations Produced by Smooth Rolling Cylinders

1. Spread (Widening)

   The forces acting on

BIOS (Basic Input/Output System): A program that resides in memory firmware EPROM. It is a model program. The BIOS is an essential part of hardware that is fully configurable and is where you control the processes of information flow in the computer bus, between the system and other peripherals. It also includes configuring the machine. Important aspects of entering the BIOS include accessing the Delete key (DEL), ESC, or another key indicated on the first screen that appears when you turn on a PC. EPROM (Erasable Programmable Read-Only Memory): is a type of ROM created by the engineer Dov Frohman. It is formed by cells or floating gate transistors. Each cell comes from the factory without charge, which is interpreted as 1. Then, voltage is... Continue reading "Understanding BIOS, EPROM, CMOS, and Motherboard Types" »

Composite Materials

Composite materials combine different components to achieve enhanced properties. Key types include:

Metal Matrix Composites

Arrays of metal, such as copper-alumina and titanium metal matrices, are used in aerospace applications with boron carbide and silicon carbide fibers.

Ceramic Matrix Composites

These are arrays of carbon graphite fibers used to improve the toughness of ceramics and maintain their properties.

Polymeric Matrix Composites

Polymeric matrices, like polyester with carbon fiber, provide flexibility and enhance the resistance of the fiber.

New Material Categories

Advances in materials research and manufacturing have enabled the creation of new materials from cheap and abundant raw materials, requiring less energy consumption.... Continue reading "Advanced Materials and Their Diverse Applications" »

Early Telephone Technology & Specifications

Alexander Graham Bell invented the telephone in 1876. Early telephony involved transistor technology. Key specifications included a central voltage of -48V, impedance ranging from 400-1750 ohms, and a 440 Hz tone. The busy tone marking was typically 350-current, with frequencies between 480-620 Hz. DTMF (Dual-Tone Multi-Frequency) technology became standard. Common cable specifications included a diameter of 0.4 mm, an impedance of 280 ohms/km, and a transmitting frequency range of 300-3400 Hz.

Subscriber & Urban Cabling

The cable inside the rosette connects old and new subscriber equipment to the Network Termination Point (NTP/PTR). Urban distribution cables, such as those used by Laredo for... Continue reading "Telecommunications Fundamentals: Network Infrastructure & Transmission" »

IPL (Initial Program Load)

IPL (Initial Program Load) -> Power On Self Test (POST)

BIOS (Basic Input/Output System)

BIOS: A set of input and output routines. It handles the communication between the operating system and hardware.

Types of Memory

• RAM (Random Access Memory): For both reading and writing.
• ROM (Read-Only Memory): For reading only.

Types of ROMs

• ROM: Read-Only Memory.
• PROM: Programmable Read-Only Memory. A digital memory where each bit's value depends on a fuse that can be burned only once.
• EPROM: Erasable Programmable Read-Only Memory. Read sequentially. Less reading provides a greater margin for error.
• EEPROM: Electrically Erasable Programmable Read-Only Memory. The signal is updated and erased with the BIOS.

RAM and ROM Classification

• Dynamic

Shipboard Equipment and Parts

Anchors

Anchor: An iron instrument, heavy and strong, shaped like a harpoon or hook. Doubled and attached to a rope, chain, or cable, it's thrown into the water to hold a vessel.

1. Plow anchor (Figure 1-37)
2. Danforth anchor (Figure 1-35)

Windlass

Windlass: A horizontal axis machine used to weigh chains. It has an iron mechanism called a chainstopper to bite and stop the chain. Often incorporates drums (Cabirol or warping ends).

Gypsy

Gypsy: A drum-shaped part of the windlass with notches or molds where the chain's mating link engages as the anchor is raised or lowered. The gypsy is in gear when turning the reel to raise the anchor, or it decouples and engages the brake to stop the shaft's rotation.

Escobar

Escobar: The location... Continue reading "Essential Shipboard Equipment and Terminology" »

Item 4: Characteristics of the Internal Combustion Engine

1. Engine Performance

Chemical Energy (Fuel) / Thermal Energy (Combustion) / Mechanical Energy (Piston Displacement)

The chemical energy contained in the fuel is converted into heat through combustion. The resulting increase in pressure moves the piston, thus obtaining mechanical energy. Efficiency is calculated as follows:

n = (Energy obtained / Energy supplied) * 100 (%)

Power Loss:

• Heat Loss: Due to the cooling system and heat transfer to the outside.
• Mechanical Losses: Friction between moving parts and driving auxiliary devices.
• Chemical Losses: Due to incomplete combustion.

2. Types of Performance

• Thermal
• Mechanical
• Effective
• Volumetric

3. Key Features of Engines

• Engine Torque
• Specific Power
• Specific

Food Market Regulations

Conditions for Food Markets

1. The flooring must be non-slip and waterproof, with adequate drainage to facilitate evacuation.
2. Walls and pillars must be covered with waterproof, smooth, and easily cleanable materials.
3. Adequate natural or mechanical lighting must be provided.
4. Running water (hot and cold), sinks, and sufficient waste disposal capacity are required.
5. Measures must be in place to prevent the entry of insects, spiders, and rodents.
6. Loading and unloading should occur through separate access points.
7. Enclosed areas are required for the exclusive use of packaging waste, with immediate access to the public highway.
8. Bathrooms with toilets, separated by gender and distinct from public areas, are necessary. Mechanical ventilation