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Sea Anchor
A sea anchor (also known as a parachute anchor, drift anchor, drift sock, para-anchor or boat brake) is a device that is streamed from a boat in heavy weather. Its purpose is to stabilize the vessel and to limit progress through the water. Rather than tethering the boat to the seabed with a conventional anchor, a sea anchor provides hydrodynamic drag (physics), drag, thereby acting as a brake. Normally attached to a vessel's Bow (ship), bows, a sea anchor can prevent the vessel from turning broadside to the waves and being overwhelmed by them. Early sea anchors were crude devices, but today most take the form of a drogue parachute. Larger sea anchors are so efficient that they need a tripping line to collapse the parachute for retrieval. Being made of fabric, a sea parachute may be bagged and easily stowed when not in use. A similar device to the sea anchor is the much smaller drogue, which is streamed from a vessel's stern in strong winds so as to slow the boat to prevent pitch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Anchor (36776431450)
A sea is a large body of water, body of salt water. There are particular seas and the sea. The sea commonly refers to the ocean, the interconnected body of seawaters that spans most of Earth. List of seas on Earth, Particular seas are either List of seas on Earth#Marginal seas by ocean, marginal seas, second-order sections of the oceanic sea (e.g. the Mediterranean Sea), or certain large, nearly landlocked bodies of water. The salinity of water bodies varies widely, being lower near the surface and the mouths of large rivers and higher in the depths of the ocean; however, the relative proportions of dissolved salts vary little across the oceans. The most abundant solid dissolved in seawater is sodium chloride. The water also contains salt (chemistry), salts of magnesium, calcium, potassium, and mercury (element), mercury, among other elements, some in minute concentrations. A wide marine life, variety of organisms, including bacteria, protists, algae, plants, fungus, fungi, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parachute
A parachute is a device designed to slow an object's descent through an atmosphere by creating Drag (physics), drag or aerodynamic Lift (force), lift. It is primarily used to safely support people exiting aircraft at height, but also serves various purposes like slowing cargo, aiding in space capsule recovery, and stabilizing vehicles or objects. Modern parachutes are typically made from durable fabrics like nylon and come in various shapes, such as dome-shaped, rectangular, and inverted domes, depending on their specific function. The concept of the parachute dates back to ancient attempts at flight. In 852 AD, Armen Firman, in Córdoba, Spain, made the first recorded jump with a large cloak to slow his fall. Renaissance figures like Francesco di Giorgio Martini and Leonardo da Vinci later sketched designs resembling modern parachutes, but it wasn’t until the 18th century that the first successful jumps occurred. French Louis-Sébastien Lenormand made the first public jump i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lehmann
Lehmann is a German surname. Geographical distribution As of 2014, 75.3% of all bearers of the surname ''Lehmann'' were residents of Germany, 6.6% of the United States, 6.3% of Switzerland, 3.2% of France, 1.7% of Australia and 1.3% of Poland. In Germany, the frequency of the surname was higher than national average in the following states: * 1. Brandenburg (1:90) * 2. Saxony (1:206) * 3. Saxony-Anhalt (1:227) * 4. Berlin (1:228) * 5. Mecklenburg-Vorpommern (1:408) * 6. Thuringia (1:493) In Switzerland, the frequency of the surname was higher than national average in the following cantons: * 1. Bern (1:240) * 2. Solothurn (1:342) * 3. Fribourg (1:486) * 4. Basel-Stadt (1:524) * 5. Jura (1:567) * 6. Thurgau Thurgau (; ; ; ), anglicized as Thurgovia, and formally as the Canton of Thurgau, is one of the 26 cantons forming the Swiss Confederation. It is composed of five districts. Its capital is Frauenfeld. Thurgau is part of Eastern Switzerland. I ... (1:606) People * Ad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Project Gutenberg
Project Gutenberg (PG) is a volunteer effort to digitize and archive cultural works, as well as to "encourage the creation and distribution of eBooks." It was founded in 1971 by American writer Michael S. Hart and is the oldest digital library. Most of the items in its collection are the full texts of books or individual stories in the public domain. All files can be accessed for free under an open format layout, available on almost any computer. , Project Gutenberg had reached over 75,999 items in its collection of free eBooks. The releases are available in plain text as well as other formats, such as HTML, PDF, EPUB, MOBI, and Plucker wherever possible. Most releases are in the English language, but many non-English works are also available. There are multiple affiliated projects that provide additional content, including region- and language-specific works. Project Gutenberg is closely affiliated with Distributed Proofreaders, an Internet-based community for proofr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phase (waves)
In physics and mathematics, the phase (symbol φ or ϕ) of a wave or other periodic function F of some real variable t (such as time) is an angle-like quantity representing the fraction of the cycle covered up to t. It is expressed in such a scale that it varies by one full turn as the variable t goes through each period (and F(t) goes through each complete cycle). It may be measured in any angular unit such as degrees or radians, thus increasing by 360° or 2\pi as the variable t completes a full period. This convention is especially appropriate for a sinusoidal function, since its value at any argument t then can be expressed as \varphi(t), the sine of the phase, multiplied by some factor (the amplitude of the sinusoid). (The cosine may be used instead of sine, depending on where one considers each period to start.) Usually, whole turns are ignored when expressing the phase; so that \varphi(t) is also a periodic function, with the same period as F, that repeatedly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wavelength
In physics and mathematics, wavelength or spatial period of a wave or periodic function is the distance over which the wave's shape repeats. In other words, it is the distance between consecutive corresponding points of the same ''phase (waves), phase'' on the wave, such as two adjacent crests, troughs, or zero crossings. Wavelength is a characteristic of both traveling waves and standing waves, as well as other spatial wave patterns. The multiplicative inverse, inverse of the wavelength is called the ''spatial frequency''. Wavelength is commonly designated by the Greek letter lambda (''λ''). For a modulated wave, ''wavelength'' may refer to the carrier wavelength of the signal. The term ''wavelength'' may also apply to the repeating envelope (mathematics), envelope of modulated waves or waves formed by Interference (wave propagation), interference of several sinusoids. Assuming a sinusoidal wave moving at a fixed phase velocity, wave speed, wavelength is inversely proportion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nylon
Nylon is a family of synthetic polymers characterised by amide linkages, typically connecting aliphatic or Polyamide#Classification, semi-aromatic groups. Nylons are generally brownish in color and can possess a soft texture, with some varieties exhibiting a silk-like appearance. As Thermoplastic, thermoplastics, nylons can be melt-processed into fibres, Thin film, films, and diverse shapes. The properties of nylons are often modified by blending with a variety of additives. Numerous types of nylon are available. One family, designated nylon-XY, is derived from diamines and dicarboxylic acids of carbon chain lengths X and Y, respectively. An important example is nylon-6,6 (). Another family, designated nylon-Z, is derived from amino acid, aminocarboxylic acids with carbon chain length Z. An example is nylon-[6]. Nylon polymers have extensive commercial applications, including uses in textiles and fibres (such as apparel, flooring and rubber reinforcement), molded components fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elastic Modulus
An elastic modulus (also known as modulus of elasticity (MOE)) is a quantity that describes an object's or substance's resistance to being deformed elastically (i.e., non-permanently) when a stress is applied to it. Definition The elastic modulus of an object is defined as the slope of its stress–strain curve in the elastic deformation region: A stiffer material will have a higher elastic modulus. An elastic modulus has the form: :\delta \ \stackrel\ \frac where stress is the force causing the deformation divided by the area to which the force is applied and strain is the ratio of the change in some parameter caused by the deformation to the original value of the parameter. Since strain is a dimensionless quantity, the units of \delta will be the same as the units of stress. Elastic constants and moduli Elastic constants are specific parameters that quantify the stiffness of a material in response to applied stresses and are fundamental in defining the elastic pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shock Absorber
A shock absorber or damper is a mechanical or hydraulics, hydraulic device designed to absorb and Damping ratio, damp shock (mechanics), shock impulses. It does this by converting the kinetic energy of the shock into another form of energy (typically thermal energy, heat) which is then dissipated. Most shock absorbers are a form of dashpot (a damper which resists motion via viscous friction). Description Pneumatic and hydraulic shock absorbers are used in conjunction with cushions and springs. An automobile shock absorber contains spring-loaded check valves and orifices to control the flow of oil through an internal piston (see below). One design consideration, when designing or choosing a shock absorber, is where that energy will go. In most shock absorbers, energy is converted to heat inside the viscous fluid. In hydraulic cylinders, the hydraulic fluid heats up, while in Pneumatic cylinder, air cylinders, the hot air is usually exhausted to the atmosphere. In other types of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Warping (sailing)
Warping or kedging is a method of moving a sailing vessel, typically against the wind or current, after running aground, or out from a dead calm, by hauling on a line attached to a kedge anchor, a sea anchor, or a fixed object, such as a bollard or tree. In small boats, the anchor may be thrown in the intended direction of progress and hauled in after it settles, thus pulling the boat in that direction, while larger ships can use a small boat to carry the anchor ahead, drop it, and then haul. For example, the sloop ''Adventure'' under the command of the infamous pirate Blackbeard ran aground attempting to kedge the ''Queen Anne's Revenge ''Queen Anne's Revenge'' was an early-18th-century ship, most famously used as a flagship by Edward Teach, better known by his nickname Blackbeard. The date and place of the ship's construction are uncertain, and there is no record of its action ...'' off the bar near Beaufort Inlet, North Carolina, in June 1718.D. Moore. (1997) "A General H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sailboat
A sailboat or sailing boat is a boat propelled partly or entirely by sails and is smaller than a sailing ship. Distinctions in what constitutes a sailing boat and ship vary by region and maritime culture. Types Although sailboat terminology has varied across history, many terms have specific meanings in the context of modern yachting. A great number of sailboat-types may be distinguished by size, hull configuration, keel type, purpose, number and configuration of masts, and sail plan. Popular monohull designs include: Cutter The cutter is similar to a sloop with a single mast and mainsail, but generally carries the mast further aft to allow for two foresails, a jib and staysail, to be attached to the head stay and inner forestay, respectively. Once a common racing configuration, today it gives versatility to cruising boats, especially in allowing a small staysail to be flown from the inner stay in high winds. Catboat A catboat has a single mast mounted far forw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War I
World War I or the First World War (28 July 1914 – 11 November 1918), also known as the Great War, was a World war, global conflict between two coalitions: the Allies of World War I, Allies (or Entente) and the Central Powers. Fighting took place mainly in European theatre of World War I, Europe and the Middle Eastern theatre of World War I, Middle East, as well as in parts of African theatre of World War I, Africa and the Asian and Pacific theatre of World War I, Asia-Pacific, and in Europe was characterised by trench warfare; the widespread use of Artillery of World War I, artillery, machine guns, and Chemical weapons in World War I, chemical weapons (gas); and the introductions of Tanks in World War I, tanks and Aviation in World War I, aircraft. World War I was one of the List of wars by death toll, deadliest conflicts in history, resulting in an estimated World War I casualties, 10 million military dead and more than 20 million wounded, plus some 10 million civilian de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
