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

Core Functions of Operating Systems

File System Structures and Types

A file system is the way information is organized and structured. Each operating system uses its own specific file system.

• FAT32: The number 32 indicates that allocation units are used in 32 bits. This file system was used in earlier versions of Windows and is currently utilized in many storage units that employ flash memory. Both Windows and GNU/Linux can read and write to units using this file system type.
• NTFS: This is the standard file system for all modern Windows versions, designed for use on large partitions.
• EXT3: This file system is used in most distributions of GNU/Linux. Windows operating systems are unable to read or write to this file system natively; however, applications

Water and Sewage

• Greywater: Waters that have been used in toilets, etc.
• Sewage: Waters that have been used to remove excrement.
• Downpipe: A conduit that carries wastewater to sewers.
• Distribution Network: Deals with the distribution of water ready to drink, called potable water.
• Siphon Outlet: U-shaped tube that always contains water to prevent the passage of odors.

Environmental Design

• Environmental Design: Aims to achieve thermal comfort inside a house naturally, taking into account the environmental conditions of the house and climate.

Broadband and Digital TV

• Broadband: A communication connection that allows faster data flow between sender and receiver.
• Decoder: A device that receives a signal and interprets it by offering a sound and signal that

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

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