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Automated Firearms Identification
Automated Firearms Identification refers to the use of computers to automate the process of matching a piece of recovered ballistic evidence (which can be either bullets or cartridge cases, or fragments thereof), against a database. Automated ballistic identification systems Every firearm leaves unique, reproducible markings on expended (used) bullet and cartridge cases that it fired. The barrel, firing pin, firing chamber, extractor, ejector and other parts of the gun leave these marks, called toolmarks, on the bullet and cartridge case faces. Individually and collectively, these markings function as the “ballistic signature” of the firearm. Traditional firearms identification involves the use of a Comparison Microscope. A firearms examiner visually compares the ballistic signature of a bullet/cartridge recovered from a crime scene with those in the police files. This process and its outcome, while accurate and acceptable in court, is extremely time consuming. Because of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ballistic Fingerprinting
Forensic firearm examination is the forensic process of examining the characteristics of firearms or bullets left behind at a crime scene. Specialists in this field try to link bullets to weapons and weapons to individuals. They can raise and record obliterated serial numbers in an attempt to find the registered owner of a weapon and look for fingerprints on a weapon and cartridges. By examining unique striations impressed into a bullet from the barrel of a gun, expended ammunition can be linked back to a specific weapon. These striations are due to the rifling inside the barrels of firearms. Rifling spins the bullet when it is fired out of the barrel to improve precision. Although bullet striations are individualized unique evidence, microscopic striations in the barrel of the weapon are subject to change slightly, after each round that is fired. For this reason, forensic ballistics examiners may not fire more than five shots from a weapon found at a scene. Known exemplars taken ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bullet
A bullet is a kinetic projectile, a component of firearm ammunition that is shot from a gun barrel. Bullets are made of a variety of materials, such as copper, lead, steel, polymer, rubber and even wax. Bullets are made in various shapes and constructions (depending on the intended applications), including specialized functions such as hunting, target shooting, training and combat. Bullets are often tapered, making them more aerodynamic. Bullet sizes are expressed by their weights and diameters (referred to as "calibers") in both imperial and metric measurement systems. For example: 55 grain .223 caliber bullets are of the same weight and caliber as 3.56 gram 5.56mm caliber bullets. Bullets do not normally contain explosives but strike or damage the intended target by transferring kinetic energy upon impact and penetration. Bullets shot by firearms can be used for target practice or hunting. Description The term ''bullet'' is from Middle French, originating as the diminutiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cartridge Case
A cartridge or a round is a type of pre-assembled firearm ammunition packaging a projectile ( bullet, shot, or slug), a propellant substance (usually either smokeless powder or black powder) and an ignition device ( primer) within a metallic, paper, or plastic case that is precisely made to fit within the barrel chamber of a breechloading gun, for the practical purpose of convenient transportation and handling during shooting. Although in popular usage the term "bullet" is often informally used to refer to a complete cartridge, it is correctly used only to refer to the projectile. Cartridges can be categorized by the type of their primers – a small charge of an impact- or electric-sensitive chemical mixture that is located: at the center of the case head (centerfire); inside the rim ( rimfire); inside the walls on the fold of the case base that is shaped like a cup (cupfire, now obsolete); in a sideways projection that is shaped like a pin (pinfire, now obsolete); ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Firing Pin
A firing pin or striker is a part of the firing mechanism of a firearm that impacts the primer in the base of a cartridge and causes it to fire. In firearms terminology, a striker is a particular type of firing pin where a compressed spring acts directly on the firing pin to provide the impact force rather than it being struck by a hammer. The terms may also be used for a component of equipment or a device which has a similar function. Such equipment or devices include: artillery, munitions and pyrotechnics. Firearms The typical firing pin is a thin, simple rod with a hardened, rounded tip that strikes and crushes the primer. The rounded end ensures the primer is indented rather than pierced (to contain propellant gasses). It sits within a hole through the breechblock and is struck by the hammer when the trigger is "pulled". A light firing-pin spring is often used to keep the firing pin rearward. It may be termed a ''firing-pin return spring'', since it returns it t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comparison Microscope
A comparison microscope is a device used to analyze side-by-side specimens. It consists of two microscopes connected by an optical bridge, which results in a split view window enabling two separate objects to be viewed simultaneously. This avoids the observer having to rely on memory when comparing two objects under a conventional microscope. History One of the first prototypes of a comparison microscope was developed in 1913 in Germany. In 1929, using a comparison microscope adapted for forensic ballistics, Calvin Goddard and his partner Phillip Gravelle were able to absolve the Chicago Police Department of participation in the St. Valentine's Day Massacre. Col. Calvin H. Goddard Philip O. Gravelle, a chemist, developed a comparison microscope for use in the identification of fired bullets and cartridge cases with the support and guidance of forensic ballistics pioneer Calvin Goddard. It was a significant advance in the science of firearms identification in forensic science. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algorithm
In mathematics and computer science, an algorithm () is a finite sequence of rigorous instructions, typically used to solve a class of specific problems or to perform a computation. Algorithms are used as specifications for performing calculations and data processing. More advanced algorithms can perform automated deductions (referred to as automated reasoning) and use mathematical and logical tests to divert the code execution through various routes (referred to as automated decision-making). Using human characteristics as descriptors of machines in metaphorical ways was already practiced by Alan Turing with terms such as "memory", "search" and "stimulus". In contrast, a heuristic is an approach to problem solving that may not be fully specified or may not guarantee correct or optimal results, especially in problem domains where there is no well-defined correct or optimal result. As an effective method, an algorithm can be expressed within a finite amount of space ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territories, nine Minor Outlying Islands, and 326 Indian reservations. The United States is also in free association with three Pacific Island sovereign states: the Federated States of Micronesia, the Marshall Islands, and the Republic of Palau. It is the world's third-largest country by both land and total area. It shares land borders with Canada to its north and with Mexico to its south and has maritime borders with the Bahamas, Cuba, Russia, and other nations. With a population of over 333 million, it is the most populous country in the Americas and the third most populous in the world. The national capital of the United States is Washington, D.C. and its most populous city and principal financial center is New York City. Paleo-Americ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Federal Bureau Of Investigation
The Federal Bureau of Investigation (FBI) is the domestic intelligence and security service of the United States and its principal federal law enforcement agency. Operating under the jurisdiction of the United States Department of Justice, the FBI is also a member of the U.S. Intelligence Community and reports to both the Attorney General and the Director of National Intelligence. A leading U.S. counterterrorism, counterintelligence, and criminal investigative organization, the FBI has jurisdiction over violations of more than 200 categories of federal crimes. Although many of the FBI's functions are unique, its activities in support of national security are comparable to those of the British MI5 and NCA; the New Zealand GCSB and the Russian FSB. Unlike the Central Intelligence Agency (CIA), which has no law enforcement authority and is focused on intelligence collection abroad, the FBI is primarily a domestic agency, maintaining 56 field offices in major cities t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drugfire
Drugfire is a multimedia database imaging system that automates the comparison of images of bullet cartridge cases, shell casings and bullets that was developed by MSI (Mnemonic System Inc.). It is a multimedia database imaging system that allows examiners from across the United States to compare and link evidence obtained in the form of spent cartridges and other ammunition casings. Development Before Drugfire was invented, firearm examiners had to rely on a technique devised in the 1920s to compare ammunition markings. This involved looking at a casing under a microscope and the examiner had to compare the two casings to see if there were similar markings on the bullet which would most likely mean that the bullets had been fired from the same gun. From the years of 1991 and 1992, MSI devolved Drugfire, a forensic imaging system that allows investigators to compare ammunition markings from a specific shooting to databases of seemingly unrelated shootings which allowed the F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bureau Of Alcohol, Tobacco And Firearms
The Bureau of Alcohol, Tobacco, Firearms and Explosives (BATFE), commonly referred to as the ATF, is a domestic law enforcement agency within the United States Department of Justice. Its responsibilities include the investigation and prevention of federal offenses involving the unlawful use, manufacture, and possession of firearms and explosives; acts of arson and bombings; and illegal trafficking and tax evasion of alcohol and tobacco products. The ATF also regulates via licensing the sale, possession, and transportation of firearms, ammunition, and explosives in interstate commerce. Many of the ATF's activities are carried out in conjunction with task forces made up of state and local law enforcement officers, such as Project Safe Neighborhoods. The ATF operates a unique fire research laboratory in Beltsville, Maryland, where full-scale mock-ups of criminal arson can be reconstructed. The ATF had 5,285 employees and an annual budget of almost $1.5 billion in 2021. The ATF ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Integrated Ballistics Identification System
The Integrated Ballistics Identification System, or ''IBIS'', is the brand of the Automated firearms identification system manufactured by Forensic Technology WAI, Inc., of Montreal, Canada. Use IBIS has been adopted as the platform of the National Integrated Ballistic Information Network (NIBIN) program, which is run by the United States Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF). NIBIN tracks about 100,000 guns used in crimes. The integration of technology into about 220 sites across the continental US and its territories facilitates sharing of information between different law enforcement groups. The rapid dissemination of ballistics information, in turn, allows for tracking of gun-specific information and connection of a particular firearm to multiple crimes irrespective of geographic location. A National Research Council report has found that with the NIBIN dataset, a bullet retrieved from a crime scene will generate about 10 possible matches, with about a 75-95 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Integrated Ballistic Identification Network
The National Integrated Ballistic Information Network or NIBIN is a specialized computer network in the United States. It contains digital images of recovered pieces of ballistic evidence. Running on the Integrated Ballistic Identification System or IBIS platform, NIBIN enables U.S. law enforcers to rapidly determine if a piece of recovered ballistic evidence came from a firearm that has been previously used in a crime. There are certain criteria that must be met prior to entering information into the NIBIN database. For instance, cartridge cases from a .22 caliber firearm or a revolver are normally not entered. Using NIBIN, law enforcement staff can identify firearms in new cases that were used in prior incidents. A series of seventeen different Washington state crime scenes involving seven firearms, and three different agencies in two counties, was identified using information provided by IBIS/NIBIN. Organizational purpose In 1999, the Bureau of Alcohol, Tobacco, Firearms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
