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Dynamic Response Index
The Dynamic Response Index (DRI) is a measure of the likelihood of spinal damage arising from a vertical shock load such as might be encountered in a military environment (i.e., during a mine blast, or in an ejection seat). The DRI is a dimensionless number which is proportional to the maximum spinal compression suffered during the event. The DRI is derived as the solution to an equation which models the human spine as a lumped single-degree-of-freedom spring-shock absorber system. The model uses an ordinary linear second-order differential equation with constant coefficients with spinal compression as the variable. The forcing function in the equation is the accelerative shock load delivered to the pelvis by the event. The equation is given below: + 2 \cdot \zeta \cdot \omega \cdot + \omega^2 \cdot X = In this equation, X denotes the spinal compression, and d2z/dt2 denotes the time-dependent shock acceleration (the input). The coefficients ω and ζ are the lumped sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinal Damage
Spine or spinal may refer to: Science Biology * Spinal column, also known as the backbone * Dendritic spine, a small membranous protrusion from a neuron's dendrite * Thorns, spines, and prickles, needle-like structures in plants * Spine (zoology), needle-like structures in animals * SPINE (molecular biology) (strep–protein interaction experiment), a method for the detection of protein interactions Medicine * Spinal anaesthesia or "a spinal", an injection generally through a fine needle, usually long * The Spine, a set of national service within the UK NHS Connecting for Health Arts, entertainment and media * ''The Spine'' (album), a 2004 They Might Be Giants album, including the songs "Spine" and "Spines" * ''Spine'' (film), American film * ''The Spine'' (film), a 2009 animated short by Chris Landreth * ''Spine'' (video game), an upcoming video game * ''The Spine'', a novel by Ladislav Bublík Fictional entities * Spinal (''Killer Instinct''), a fictional character from t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertical Shock Load
Vertical is a geometric term of location which may refer to: * Vertical direction, the direction aligned with the direction of the force of gravity, up or down * Vertical (angles), a pair of angles opposite each other, formed by two intersecting straight lines that form an "X" * Vertical (music), a musical interval where the two notes sound simultaneously * "Vertical", a type of wine tasting in which different vintages of the same wine type from the same winery are tasted * Vertical Aerospace, stylised as "Vertical", British aerospace manufacturer * Vertical kilometer, a discipline of skyrunning * Vertical market, a market in which vendors offer goods and services specific to an industry * Vertical integration, a management term describing a style of ownership and control Media * ''Vertical'' (film), a 1967 Soviet movie starring Vladimir Vysotsky * "Vertical" (''Sledge Hammer!''), 1987 television episode * ''Vertical'' (novel), 2010 novel by Rex Pickett * Vertical (film comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
STANAG 4569
NATO AEP-55 STANAG 4569 is a NATO Standardization Agreement covering the standards for the "Protection Levels for Occupants of Logistic and Light Armored Vehicles". The standard covers strikes from kinetic energy, artillery and Improvised explosive device, IED Explosion, blasts. STANAG 4569 Protection Levels Level 1 Kinetic Energy 7.62×51mm NATO Ball (Ball M80) at 30 meters with velocity 833 ± 20 m/s 5.56×45mm NATO Ball (SS109) at 30 meters with a velocity of 900 ± 20 m/s 5.56×45mm NATO Ball (M193) at 30 meters with a velocity of 937 ± 20m/s Protection against all three threats must be provided. Grenade and Mine Blast Hand grenades, unexploded artillery fragmenting submunitions, and other small anti personnel explosive devices detonated under the vehicle. Artillery 155 mm High Explosive at 100 m Angle: Azimuth 360°; elevation: 0–18° Level 2 Kinetic Energy 7.62×39mm API BZ at 30 meters with 695 ± 20 m/s Grenade and Mine Blast Threat 6 kg (explosive mas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Back Injury
Back injuries result from damage, wear, or trauma to the bones, muscles, or other tissues of the back. Common back injuries include sprains and strains, Spinal disc herniation, herniated discs, and Vertebral compression fracture, fractured vertebrae. The lumbar spine is often the site of back pain. The area is susceptible because of its flexibility and the amount of body weight it regularly bears. It is estimated that low-back pain may affect as much as 80 to 90 percent of the general population in the United States.Putz-Anderson, Vern, Thomas Waters, and Arun Garg. (1994)Applications Manual for the Revised NIOSH Lifting Equation National Institute for Occupational Safety and Health. NIOSH (DHHS) Publication 94–110. Classification Soft tissue graded system Muscle and soft tissue injuries can be classified using a graded system. * Grade 1 muscle strain is the least severe with damage to few muscle fibers and little if any loss of function. * Grade 2 muscle strain indicates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crashworthiness
Crashworthiness is the ability of a structure to protect its occupants during an impact. This is commonly tested when investigating the safety of aircraft and vehicles. Different criteria are used to figure out how safe a structure is in a crash, depending on the type of impact and the vehicle involved. Crashworthiness may be assessed either prospectively, using computer models (e.g., RADIOSS, LS-DYNA, PAM-CRASH, MSC Dytran, MADYMO) or experiments, or retrospectively, by analyzing crash outcomes. Several criteria are used to assess crashworthiness prospectively, including the deformation patterns of the vehicle structure, the acceleration experienced by the vehicle during an impact, and the probability of injury predicted by human body models. Injury probability is defined using criteria, which are mechanical parameters (e.g., force, acceleration, or deformation) that correlate with injury risk. A common injury criterion is the head impact criterion (HIC). Crashworthiness is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ejection Seat
In aircraft, an ejection seat or ejector seat is a system designed to rescue the aircraft pilot, pilot or other aircrew, crew of an aircraft (usually military) in an emergency. In most designs, the seat is propelled out of the aircraft by an explosive charge or rocket motor, carrying the pilot with it. The concept of an ejectable escape crew capsule has also been tried (see B-58 Hustler). Once clear of the aircraft, the ejection seat deploys a parachute. Ejection seats are common on certain types of military aircraft. History A bungee cord, bungee-assisted escape from an aircraft took place in 1910. In 1916, Everard Calthrop, an early inventor of parachutes, patented an ejector seat using compressed air. Compression springs installed under the seat were tested. The modern layout for an ejection seat was first introduced by Romanian inventor Anastase Dragomir in the late 1920s. The design featured a ''parachuted cell'' (a dischargeable chair from an aircraft or other vehicle) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spinal Injury
A spinal cord injury (SCI) is damage to the spinal cord that causes temporary or permanent changes in its function. It is a destructive neurological and pathological state that causes major motor, sensory and autonomic dysfunctions. Symptoms of spinal cord injury may include loss of muscle function, sensation, or autonomic function in the parts of the body served by the spinal cord below the level of the injury. Injury can occur at any level of the spinal cord and can be ''complete'', with a total loss of sensation and muscle function at lower sacral segments, or ''incomplete'', meaning some nervous signals are able to travel past the injured area of the cord up to the Sacral S4-5 spinal cord segments. Depending on the location and severity of damage, the symptoms vary, from numbness to paralysis, including bowel or bladder incontinence. Long term outcomes also range widely, from full recovery to permanent tetraplegia (also called quadriplegia) or paraplegia. Complications can in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
