• Journal of Broadcast Engineering
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• v.23 no.6
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• pp.780-789
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• 2018

Nowadays, gun crimes occur very frequently not only in public places but in alleyways around the world. In particular, it is essential to detect a person armed by a pistol to prevent those crimes since small guns, such as pistols, are often used for those crimes. Because conventional works for armed person detection have treated an armed person as a single object in an input image, their accuracy is very low. The reason for the low accuracy comes from the fact that the gunman is treated as a single object although the pistol is a relatively much smaller object than the person. To solve this problem, we propose a novel algorithm called APDA(Armed Person Detection Algorithm). APDA detects the armed person using in a post-processing the positions of both wrists and the pistol achieved by the CNN-based human body feature detection model and the pistol detection model, respectively. We show that APDA can provide both 46.3% better recall and 14.04% better precision than SSD-MobileNet.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.04a
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• pp.481-486
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• 2010

본 논문은 실내사격장 화재 원인에 대한 조사를 위하여 권총 사용에 따른 화약잔사 양에 대한 실측 및 발화특성에 관하여 연구하였다. 화약잔사 양의 실측은 1차로 사대 부분을 밀폐한 상태에서 실내사격장에 사용되는 권총과 동일한 구경 0.38인치 권총 및 구경 9mm 권총을 5발 발사하여 총구 및 약실로 분출되는 화약잔사의 양을 측정하였으며, 2차로 사대 개방 후, 구경 0.38인치 권총을 100발 발사하는 경우, 사대 바닥면에 떨어지는 화약잔사의 양을 측정하였다. 화약잔사에 대한 발화특성은 충격 감도, 정전기 감도, 마찰 감도 및 발화점 시험을 실시하였으며, 비교 평가에는 권총에 일반적으로 사용되는 사용전의 화약(ball powder)을 이용하여 화약잔사와 동일한 시험을 실시하였다. 실험결과 충격감도 및 마찰강도는 화약잔사에서 다소 높게 측정되었으며, 발화점 시험에서는 화약잔사가 비교대상인 사용전의 화약에 비해 낮은 온도에서 발화되는 특성을 나타내었다.

• Fire Science and Engineering
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• v.24 no.5
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• pp.102-106
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• 2010

This paper studied the measurement about the gunpowder residue quantity by using a handgun and we carried out an experiment ignition characteristics of the gunpowder residue for the investigation fire cause into the indoor shooting range in Busan. The measurement of the gunpowder residue quantity is spouted by using a 0.38 inch gun and 9 mm gun. We were carried out evaluation experiments such as impact sensitivity test, static electricity sensitivity test, friction sensitivity test and measuring a flash point for the ignition characteristics about the gunpowder residue. From experiment results, the impact sensitivity and friction sensitivity of the gunpowder residue in comparison with ball powder are highly sensitive and the gunpowder residue ignites at a relatively low temperature.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.1 s.94
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• pp.87-94
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• 1999

The peak recoil force in a pistol have an effect on the reliability of the frame and target shooting. The experimental system has been established for measurement of the peak recoil force, which consists of force and velocity sensors, high speed camera. For effective operation of the system, a software has also developed, and combined with the hardwares. Several pistols have been tested and compared quantitatively on the peak recoil force and impact energy. It is concluded that the established system can be utilzed for checking peak force, and data accumulation for new pistol design.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.1033-1036
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• 1996

In Pistol, the peak recoil force affects the reliability of the frame and the accuracy of target shooting. To attenuate the peak recoil force of pistol, we develop measuring test bed, which consists of force sensors, linear sensor and a high speed video camera, execute tests with several Pistol models and compare the results measured.

• Analytical Science and Technology
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• v.23 no.3
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• pp.322-329
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• 2010

Primer gunsot residues (GSR) obtained from K1A and K2 rifles, and K5 pistol were analysed with scanning electron microscopy/energy dispersive X-ray spectrometry (SEM-EDX) as basic data in firearm accidents. Ammunition of 5.56 mm is employed for K1A and K2 rifles and 9.0 mm for a K5 pistol. The analyses of morphology, size, particle number, elemental ratio were performed for primer GSR prepared after shooting 3 times. The detected content was Ba>Pb>Sb in most GSR particles but Sb>Pb>Ba or Pb>Sb>Ba in some particles. In the statistical result of composition ratio of elements, the particles with more Sb than Ba were detected in most primer GSR from a K5 pistol, 3~8 times more than K1A and K2 rifles. This results can be employed to discriminate gun type between rifles and pistols. Furthermore, the size and the number of particles can be applied to access the type of guns.

• Korean Journal of Applied Biomechanics
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• v.19 no.3
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• pp.509-517
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• 2009

The purpose of this study was to investigate the effective posture for air pistol shooting. Participants were 3 male athletes of shooting with at least five years of experience and another group of 3 males athletes with less than three years of experience. For the purpose, the shooting motion was analysed using three dimensional image technology. Data from each event for the two groups, competent and less competent ones, were compared to see the differences from the kinematical point of view. Time of period in competent group was longer than less competent group during the shooting posture. Displacement of center of mass and pistol about medial/lateral and antero/posterior in competent group was little than less competent group from aim to shooting. And these result were effect to the velocity. Distance and time in competent group within coaching machine were smaller than less competent group. To the result, it was appear that precision of aim in competent group was higher than less competent group.

• Korean Security Journal
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• no.14
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• pp.367-388
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• 2007

Some of individuals working at various fields of security guard are given the legal right to use a gun to cope with expected risks and crimes. Not only in Korea but also throughout the world, a pistol is being used as a device for the workers of security guard such as the army, the police and intelligence agencies to keep the law and social order. A pistol, which is regarded as the last safety measure of security guard, is easy to carry but, because of its short barrel for high portability, its hit ratio and long-range shooting performance are much lower than ordinary guns. Despite such weak points, a pistol can be a great tool because of its high portability and if the users make steady efforts to improve their skills and, for this reason, it has been being used widely until now. National agency workers' pistol shooting skills depend on several important factors, but for the fast and accurate shooting, the mot important factor is how to aim at the target. Because it takes a relatively longer time to align the sight on the target, the change of the sight alignment method is expected to improve pistol shooting skills a lot. In Korea, however, most of national agency training centers teach the basic aiming method that crosses the foresight and the backsight and aligns the crossing to the target. That is, they teach the sight alignment method for fixed targets. Some agencies in Korea and foreign countries that have used guns more frequently and longer than us are teaching different sight alignment methods as well. Representative ones of them are aiming only with the foresight and pointing shooting. These aiming methods are expected to produce good results against moving targets. While the basic sight alignment method has to cross the foresight and the backsight and then to align the crossing to the target, so takes a longer time than other aiming methods, the other two aiming methods are expected to be effective in fields where both swiftness and accuracy are require. Because domestic agencies are teaching mainly the basic sight alignment method, the present study purposed to examine the effects of different aiming methods on shooting records and ultimately to contribute to national agency workers' operation. For this purpose, we selected 20 policemen from local police commandos under the National Police Agency who were accustomed to pistol shooting and measured their pistol shooting. According to the results, the pointed shooting method showed the best record in 5m short.range shooting. As to hit ratio in 15m shooting, which is relatively long.range for pistol shooting, the basic aiming method showed the best record, but the results of statistical analysis showed that pointed shooting is most superior. Of course, the results were obtained from a group who were used to and skillful in pistol shooting, but they are considered meaningful in that all the police and national agency workers should have such high shooting skills.

• Journal of Korean Electronics
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• v.4 no.11
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• pp.92-96
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• 1984

• The Science & Technology
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• no.5 s.456
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• pp.48-53
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• 2007