Understanding Hard Disk Structure: Physical, Logical, and File Systems
1. Physical Structure
A hard disk case is tightly composed of two non-interchangeable elements:
- Read/Write Head: A set of electronic and mechanical components enabling data storage and retrieval.
- Disk (Platter): A disk array (plates) storing information magnetically. One plate has two magnetic surfaces (top and bottom) composed of millions of magnetized elements representing bits (0 or 1).
Eight contiguous bits form one byte (one character).
1.1. Hard Disk Mechanics
Mechanisms for accessing data on the
Read MoreComprehensive Guide to Marine Equipment and Terminology
Anchor |
Instrument of iron or heavy and strong, in the form of a harpoon or hook. |
Double that, attached to the end of a rope, chain, or cable to the vessel and |
thrown into the water, holding the ship in the background. |
1. Plow anchor. Figure 1-37. |
2. Danforth anchor. Figure 1-35. |
Windlass |
Horizontal axis machine used to weigh chains, which has an |
iron mechanism called chainstopper used to bite and stop |
the chain. Often incorporates drums (Cabirol or warping ends) goes |
charge ends. |
Gypsy |
Part of the windlass |
Overhead Power Line Design: Conductor Sizing, Wind Loads, and Grounding
Overhead Power Line Design
Conductor Sizing and Materials
The minimum allowable conductor sizes are 16 mm2 for aluminum and 10 mm2 for copper. These values apply to bare, insulated conductors rated for voltages less than 0.6/1 kV.
Permanent Loads
Permanent loads include the vertical forces due to the weight of conductors, insulators, clamps, and supports.
Wind Load Considerations
Overload from wind pressure is calculated as follows:
- Conductors: 50 daN/m2
- Flat surfaces: 100 daN/m2
- Cylindrical supports: 70
Ferrous Metals and Steel Production: A Comprehensive Overview
Ferrous Metals: An Introduction
Ferrous metals are those containing iron as a base element. They can also include small proportions of other elements.
Major Mineral Deposits
- Polanco
- Preserve Wagner
- Black Eyes
- Agrominsa
- Sherry Villafranca
- Alquife
- Riotinto
- Aznalcollar
- Tharsis
Types of Iron Ore
- Magnetite
- Hematite
- Limonite
- Siderite
Iron Ore Processing and the Blast Furnace
Gathering and Preparation
Iron ore undergoes crushing and grinding before entering the blast furnace. The useful ore is then separated from non-coking
Read MoreComputer Security Threats: Viruses, Malware, and Exploits
What is a Computer?
A computer (from the Latin computare, meaning “to estimate”) is an electronic device that processes data to produce useful information. It consists of integrated circuits and components that execute instructions with speed and accuracy, based on user input or automated programs. This process, known as programming, enables a wide range of practical applications.
Computers require both software (instructions) and specific data (input) to generate output (processed information).
Read MoreUnbundled & Shared DSL Access Technologies for the Local Loop
1. Alternative ISPs in Areas Without Coverage
In areas where alternative ISP networks lack access to Telefónica’s ADSL infrastructure, two main options exist. The speed of these options reflects the market conditions at the time of Telefónica’s recruitment.
ADSL Resold (Almost Obsolete)
This service, based on GigADSL, was used by alternative operators in the early days of ADSL. The alternative ISP rents all connection layers from Telefónica, including ATM, IP address, and transport network to a
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