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Boomerang (mobile Shooter Detection System)
Boomerang is a gunfire locator developed by DARPA and BBN Technologies primarily for use against snipers. Boomerang is mounted on mobile vehicles such as the Humvee, Stryker, and MRAP combat vehicles. There were plans to integrate it into the Land Warrior system. Development Boomerang grew out of a program conceived by the U.S. Department of Defense in late 2003, months after the traditional combat phase of the Iraq War had ended on 1 May, at a time when it was clear that U.S. troops were increasingly at risk from a growing and aggressive insurgency. Often, troops in noisy Humvees did not know they were being shot at until someone was hit. U.S. Defense Secretary Donald Rumsfeld approached DARPA and asked for near-term solutions that could be applied to the conflict in Iraq. Rumsfeld was looking for something that did not have to be a perfect solution, but was at least better than nothing. The U.S. Army and Special Operations Command began using a limited number of French-m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boomerang 3 Gunfire Acoustic Detection System MOD 45153048
A boomerang () is a thrown tool typically constructed with airfoil sections and designed to spin about an axis perpendicular to the direction of its flight, designed to return to the thrower. The origin of the word is from Australian Aboriginal languages, an Aboriginal Australian language of the Sydney region. Its original meaning, which is preserved in official competitions, refer only to returning objects, not to throwing sticks, which were also used for hunting by various peoples both in Australia and around the world. However, the term "non-returning boomerang" is also in general use. Various forms of boomerang-like designs were traditionally and in some cases are still used by some groups of Aboriginal Australians for hunting. The tools were known by various names in the many Aboriginal languages prior to Colonisation of Australia, colonisation. The oldest surviving Aboriginal boomerang, now held in the South Australian Museum, was found in a peat bog in South Australia, d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ricochets
A ricochet ( ; ) is a rebound, bounce, or skip off a surface, particularly in the case of a projectile. Most ricochets are caused by accident and while the force of the deflection decelerates the projectile, it can still be energetic and almost as dangerous as before the deflection. The possibility of ricochet is one of the reasons for the common firearms safety rule "Never shoot a bullet at a flat, hard surface." Ricochets can occur with ''any'' caliber, but short or round ricocheting bullets may not produce the audible whine caused by tumbling irregular shapes. Ricochets are a hazard of shooting because, for as long as they retain sufficient velocity, ricocheting bullets or bullet fragments may cause collateral damage to animals, objects, or even the person who fired the shot. Variables Ricochets occur when a bullet or bullet fragment is deflected by an object rather than penetrating and becoming embedded in that object. Ricochet behavior may vary with bullet shape, bullet ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Army Equipment
United may refer to: Places * United, Pennsylvania, an unincorporated community * United, West Virginia, an unincorporated community Arts and entertainment Films * ''United'' (2003 film), a Norwegian film * ''United'' (2011 film), a BBC Two film * ''The United'' (film), an unreleased Arabic-language film Literature * ''United!'' (novel), a 1973 children's novel by Michael Hardcastle Music * United (band), Japanese thrash metal band formed in 1981 Albums * ''United'' (Commodores album), 1986 * ''United'' (Dream Evil album), 2006 * ''United'' (Marvin Gaye and Tammi Terrell album), 1967 * ''United'' (Marian Gold album), 1996 * ''United'' (Phoenix album), 2000 * ''United'' (Woody Shaw album), 1981 Songs * "United" (Judas Priest song), 1980 * "United" (Prince Ital Joe and Marky Mark song), 1994 * "United" (Robbie Williams song), 2000 * "United", a song by Danish duo Nik & Jay featuring Lisa Rowe * "United (Who We Are)", a song by XO-IQ, featured in the television serie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sound Ranging
In physics, sound is a vibration that propagates as an acoustic wave through a transmission medium such as a gas, liquid or solid. In human physiology and psychology, sound is the ''reception'' of such waves and their ''perception'' by the brain. Only acoustic waves that have frequencies lying between about 20 Hz and 20 kHz, the audio frequency range, elicit an auditory percept in humans. In air at atmospheric pressure, these represent sound waves with wavelengths of to . Sound waves above 20 kHz are known as ultrasound and are not audible to humans. Sound waves below 20 Hz are known as infrasound. Different animal species have varying hearing ranges, allowing some to even hear ultrasounds. Definition Sound is defined as "(a) Oscillation in pressure, stress, particle displacement, particle velocity, etc., propagated in a medium with internal forces (e.g., elastic or viscous), or the superposition of such propagated oscillation. (b) Auditory sensa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boston Marathon Bombing
The Boston Marathon bombing, sometimes referred to as simply the Boston bombing, was an Islamist domestic terrorist attack that took place during the 117th annual Boston Marathon on April 15, 2013. Brothers Tamerlan and Dzhokhar Tsarnaev planted two homemade pressure cooker bombs that detonated near the finish line of the race 14 seconds and apart. Three people were killed and hundreds injured, including a dozen who lost limbs. On April 18, 2013, the Federal Bureau of Investigation (FBI) released images of two suspects in the bombing. The two suspects were later identified as the Tsarnaev brothers. Later on the evening of April 18, the Tsarnaev brothers killed an MIT policeman, Sean Collier, and proceeded to commit a carjacking. They engaged in a shootout with police in nearby Watertown, during which two officers were severely injured (one of the injured officers, Dennis Simmonds, died a year later). Tamerlan was shot several times, and his brother Dzhokhar ran him o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
US Army
The United States Army (USA) is the primary land service branch of the United States Department of Defense. It is designated as the Army of the United States in the United States Constitution.Article II, section 2, clause 1 of the United States Constitution (1789).See alsTitle 10, Subtitle B, Chapter 301, Section 3001 It operates under the authority, direction, and control of the United States secretary of defense. It is one of the six armed forces and one of the eight uniformed services of the United States. The Army is the most senior branch in order of precedence amongst the armed services. It has its roots in the Continental Army, formed on 14 June 1775 to fight against the British for independence during the American Revolutionary War (1775–1783). After the Revolutionary War, the Congress of the Confederation created the United States Army on 3 June 1784 to replace the disbanded Continental Army.Library of CongressJournals of the Continental Congress, Volume 27/ref> Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azimuth
An azimuth (; from ) is the horizontal angle from a cardinal direction, most commonly north, in a local or observer-centric spherical coordinate system. Mathematically, the relative position vector from an observer ( origin) to a point of interest is projected perpendicularly onto a reference plane (the horizontal plane); the angle between the projected vector and a reference vector on the reference plane is called the azimuth. When used as a celestial coordinate, the azimuth is the horizontal direction of a star or other astronomical object in the sky. The star is the point of interest, the reference plane is the local area (e.g. a circular area with a 5 km radius at sea level) around an observer on Earth's surface, and the reference vector points to true north. The azimuth is the angle between the north vector and the star's vector on the horizontal plane. Azimuth is usually measured in degrees (°), in the positive range 0° to 360° or in the signed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elevation (ballistics)
In ballistics, the elevation is the angle between the horizontal plane and the axial direction of the barrel (firearms), barrel of a gun, Mortar (weapon), mortar or heavy artillery. Originally, elevation was a ''linear'' measure of how high the gunners had to physically lift the muzzle (firearm), muzzle of a gun up from the gun carriage to compensate for projectile drop and hit targets at a certain distance. Until WWI Though early 20th-century firearms were relatively easy to fire, artillery was not. Before and during World War I, the only way to effectively fire artillery was plotting points on a plane. Most artillery units seldom employed their guns in small numbers. Instead of using pin-point artillery firing they used old means of "fire for effect" using artillery en masse. This tactic was employed successfully by past armies. By World War I, reasonably accurate artillery fire was possible even at long range requiring significant elevation. However, artillery tactics used i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Range Of A Projectile
In physics, a projectile launched with specific initial conditions will have a range. It may be more predictable assuming a flat Earth with a uniform gravity field, and no air resistance. The horizontal ranges of a projectile are equal for two complementary angles of projection with the same velocity. The following applies for ranges which are small compared to the size of the Earth. For longer ranges see sub-orbital spaceflight. The maximum horizontal distance travelled by the projectile, neglecting air resistance, can be calculated as follows: Note that the source's y-y0 is replaced with the article's y0 : where * d is the total horizontal distance travelled by the projectile. * v is the velocity at w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sonic Boom
A sonic boom is a sound associated with shock waves created when an object travels through the air faster than the speed of sound. Sonic booms generate enormous amounts of sound energy, sounding similar to an explosion or a thunderclap to the human ear. The crack of a supersonic bullet passing overhead or the crack of a bullwhip are examples of a small sonic boom. Sonic booms due to large supersonic aircraft can be particularly loud and startling, tend to awaken people, and may cause minor damage to some structures. This led to the prohibition of routine supersonic flight overland. Although sonic booms cannot be completely prevented, research suggests that with careful shaping of the vehicle, the nuisance due to sonic booms may be reduced to the point that overland supersonic flight may become a feasible option. A sonic boom does not occur only at the moment an object crosses the sound barrier and neither is it heard in all directions emanating from the supersonic objec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muzzle Blast
A muzzle blast is an explosive shockwave created at the muzzle of a firearm during shooting. Before a projectile leaves the gun barrel, it obturates the bore and "plugs up" the pressurized gaseous products of the propellant combustion behind it, essentially containing the gases within a closed system as a neutral element in the overall momentum of the system's physics. However, when the projectile exits the barrel, this functional seal is removed and the highly energetic bore gases are suddenly free to exit the muzzle and rapidly expand in the form of a supersonic shockwave (which can often be fast enough to momentarily overtake the projectile and affect its flight dynamics), thus creating the muzzle blast. The muzzle blast is often broken down into two components: an auditory component and a non-auditory component. The auditory component is the loud "Bang!" sound of the gunshot, and is important because it can cause significant hearing loss to surrounding personnel an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microphone
A microphone, colloquially called a mic (), or mike, is a transducer that converts sound into an electrical signal. Microphones are used in many applications such as telephones, hearing aids, public address systems for concert halls and public events, motion picture production, live and recorded audio engineering, sound recording, two-way radios, megaphones, and radio and television broadcasting. They are also used in computers and other electronic devices, such as mobile phones, for recording sounds, speech recognition, Voice over IP, VoIP, and other purposes, such as Ultrasonic transducer, ultrasonic sensors or knock sensors. Several types of microphone are used today, which employ different methods to convert the air pressure variations of a sound wave to an electrical signal. The most common are the dynamic microphone, which uses a coil of wire suspended in a magnetic field; the condenser microphone, which uses the vibrating Diaphragm (acoustics), diaphragm as a capacitor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
