Device that constrains the path of electromagnetic waves (see electromagnetic radiation). It can be used to transmit power or signals in the form of waves while minimizing power loss. Common examples are metallic tubes, coaxial cables, and optical fibres (see fibre optics). Waveguides transmit energy by propagating transmitted electromagnetic waves through the inside of a tube to a receiver at the other end. Metal waveguides are used in such technologies as microwave ovens, radar systems, radio relay systems, and radio telescopes.
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Dog professionally trained to guide and protect its blind master. They have also been used to assist persons with hearing impairments and restricted mobility. Systematic training of guide dogs originated in Germany during World War I to aid blinded veterans. At the age of approximately one year, the dog is trained for three or four months. Retrievers and German shepherds are the most widely used breeds.
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Mountain guides are those employed in mountaineering; these are not merely to show the way but stand in the position of professional climbers with an expert knowledge of rock and snowcraft, which they impart to the amateur, at the same time assuring the safety of the climbing party. This professional class of guides arose in the middle of the 19th century when Alpine climbing became recognized as a sport.
In Switzerland, the central committee of the Swiss Alpine Club issues a guides’ tariff which fixes the charges for guides and porters; there are three sections, for the Valais and Vaudois Alps, for the Bernese Oberland, and for central and eastern Switzerland.
In Chamonix (France)a statue has been raised to Jacques Balmat, who was the first to climb Mont Blanc in 1786. Other notable European guides are Auguste Balmat, Michel Cros, Maquignay, J. A. Carrel, who accompanied Edward Whymper to the Andes, the brothers Lauener, Christian Almer and Jakob and Melchior Anderegg.
A psychedelic guide is someone who guides a drug user's experiences as opposed to a sitter who merely remains present, ready to discourage bad trips and handle emergencies but not otherwise getting involved. Guides are more common amongst spiritual users of entheogens. Psychedelic guides were strongly encouraged by Timothy Leary and the other authors of The Psychedelic Experience: A Guide Based on the Tibetan Book of the Dead. Trip sitters are also mentioned in the Responsible Drug User's Oath.
The genesis of the "Guides" regiments may be found in a short-lived Corps of Guides formed by Napoleon in Italy in 1796, which appears to have been a personal escort or body guard composed of men who knew the country. Following the unification of Italy in 1870-71, the new national army included a regiment designated as Guides - the 19th Cavalleggieri (Light Horse).
In the Belgian army the two Guides regiments constituted part of the light cavalry, and came to correspond to the Guard cavalry of other nations.
In the Swiss army prior to 1914 the squadrons of "Guides" acted as divisional cavalry. In this role these light cavalry units were called upon, on occasion, to lead columns.
The "Queen’s own Corps of Guides" of the British Indian Army consisted of a unique combination of infantry companies and cavalry squadrons. After World War I the infantry element was incorporated in the 12th Frontier Force Regiment and the Guides Cavalry formed a separate regiment.
In drill, a "guide" is an officer or non-commissioned officer who regulates the direction and pace of movements.