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- 저자 : Deuksu Park (검색결과 5 건)
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알루미늄 2024 표적에 대한 HE 탄두 파편의 관통 특성 연구
김득수(Deuksu Kim),강순부(Sunbu Kang),정대한(Daehan Jung),정영진(Youngjin Chung),박용헌(Yongheon Park),박세권(Seikwon Park),황창수(Changsu Hwang) 한국항공우주학회 2018 韓國航空宇宙學會誌 Vol.46 No.3
본 논문은 한국형 전투기 개발 시 적의 위협에 대한 취약성 분석을 위해 요구되는 고속관통자가 표적을 관통하는 기구에 대해 수치 해석적으로 연구한 결과이다. 표적은 1 mm~6.3mm 두께를 갖는 준 무한평면의 알루미늄(Aluminum) 2024 재질을 고려하였다. 관통자는 반구형 노즈 형상을 갖는 강(steel) 재질로, 입사속도는 350~3353 m/s까지, 질량은 0.32~16g까지 갖는 것으로 고려하였다. 수치해석을 위해 사용된 실 사격 데이터는 THOR 방정식으로부터 추정하여 유추하였다. 수치해석 결과 표적을 관통하는 과정에서 관통자의 탄도한 계속도는 관통자의 질량에 대한 지수 함수적으로 감소하는 수식으로 형식화(closed form of formalization) 하였다. 관통 후 잔류속도 및 잔류질량은 표적의 두께와 관통자의 질량 및 입사속도에 의존된 지수 함수적으로 감소하는 수식으로 각각 형식화하였다. We have studied the damage mechanism of a metallic thin plate by the highly energetic fragments generated from high explosive(HE) warhead. The penetration process has presumed that the velocity of a fragment is in the range of 350 m/s to 3353 m/s, the thickness of Aluminum 2024 target plate is in the range of 1 mm~6.3 mm thick. The mass of fragment with hemisphere nose shape is in the range of 0.32 g to 16 g. The analytical solution for penetration process has been derived by using the report of the project THOR. The results of analysis implied that the closed forms by an exponentially decay function well fit the change of the ballistic limit velocity, loss velocity and loss mass of fragment as the mass of fragment and the thickness of target plate increase.
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박명환(Myunghwan Park),김득수(Deuksu Kim),김동한(Donghan Kim),설현주(Hyeonju Seol) 육군사관학교 화랑대연구소 2018 한국군사학논집 Vol.74 No.1
The demand for well-educated cyber warfare professionals is sharply increasing these days and it is clear that military academy should do the pivotal roles to cultivate such cyber warriors. For the sake of it, the current curriculum of military academy should be revised to make it best-fit to accommodate this challenging mission. To do that, we first surveyed several cyber security curricula of other institutions and previous researches on curriculum for cyber security. We then identified key knowledge areas required for cyber warfare and designed the class courses for the corresponding knowledge areas. Finally, we proposed cyber warfare centered curricula for each academy, which could be incorporated with the current curricula with a minor change.
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A Survey of Injuries and a Comparative Study of Characteristics for Each Detailed Sport of TAEKWONDO
Youngnam Cha,Deuksu Park J-INSTITUTE 2021 International Journal of Martial Arts Vol.6 No.3
Purpose: This study was conducted to examine the status of injuries by each detailed sport of Taekwondo and provide the basic data for developing an injuries prevention program appropriate for the characteristics of each sport. Method: A total of 110 college and university Taekwondo athletes were targeted, including 35 for competition, 33 for poomsae, and 42 for demonstration, respectively, and the status of injuries and treatment methods were surveyed and analyzed. The results are as follows. Results: First, as for the injuries related experiences, 82.4% of those for competition, 69.7% of those for poomsae, and 78% of those for demonstration turned out to have had relevant experiences, and as for the sur-gery related experiences by each sport, those for competition were 44.1%, those for poomsae were 15.2%, and those for demonstration were 21.4%, respectively. Second, as a result of analyzing the their recovery period, those for sparing were 28.6% and those for demonstration were 42.9% responding with less than 4 weeks at the most. Meanwhile, those for poomsae demonstrated the highest rate of 36.4% for over 6 months. Third, as a result of analyzing the situation of injuries, those for competition were 80%, those for poomsae were 78.8%, and those for demonstration were 63.4%, responding that they have suffered most injuries during this sport. Fourth, as a result of analyzing the causes of injuries, 24% of those for competition responded with collision or fall the most. 21.7% of those for poomsae and 25% of those for demonstration responded fatigue and overwork as the causes of inju-ries the most. Fifth, as a result of analyzing the timing of injuries, 36.8% of those for competition, 42.6% of those for poomsae, and 38.4% of those for demonstration responded that they have suffered the most injuries during the winter. Sixth, as a result of analyzing the types of injuries, sprains and fractures accounted for the most with 17.7%, respectively, while 18.9% of those for poomsae and 25.2% of those for for demonstration responded the most with sprain. Seventh, as a result of analyzing the parts of injuries, 28.8% of those for competition, 34.5% of those for poomsae, and 34.5% of those for demonstration responded the most with lower body injuries. Lastly, as a result of analyzing the method of handling injuries, 24.7% of those for competition, 19.6% of those for poomsae, and 19.9% of those for demonstration responded the most with treatment after visiting an oriental medicine clinic. Conclusion: Gathering which, given the high frequency of sports injuries for the athletes, conditioning is need-ed, and it is also determined that the measures for maintaining body temperature and preventing injuries are required during the winter exercises. Furthermore, given the characteristics of Taekwondo, the frequency of use of the lower body is quite high, and as it is evident that the lower body injuries are prevalent, and since there are many sprains and fractures, in line with the causes and types of such injuries, systematic training methods for improving the athletes performance and preventing injuries, and such preventive methods as taping, braces, and warm-up exercises would likely be required.
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실린더형 HE 탄두 폭발 시 파편의 속도 및 발사각 추정방법 연구
황창수(Changsu Hwang),박용헌(Younghyun Park),박세권(Seikwon Park),정대한(Daehan Jung),이문식(Moonsik Lee),강순부(Sunbu Kang),김득수(Deuksu Kim) 한국항공우주학회 2019 韓國航空宇宙學會誌 Vol.47 No.12
본 연구는 항공기에 근접하여 폭발하는 고폭형 위협 무기의 파편 발사속도 및 발사각을 수치 해석적으로 추정한 결과이다. 고폭형 위협 무기에 대한 항공기의 취약성을 평가하기 위하여 탄두 구성품의 물리량을 이해하는 것은 매우 중요하다. 일반적으로 고폭형 위협 무기에 대한 구성품의 질량, 길이 및 직경 등 물리적 변수는 알려져 있지 않다. Terrier, Sparrow 등 유사 위협 무기들의 데이터를 이용하여 charge to mass 비율, 길이와 직경 비율 등과 관련된 경험식을 수치 해석적으로 유도하였다. 근접신관에 의하여 외부에 폭발하는 탄두에서 탄두 덮개 구성비는 20% 수준으로 나타났으며, 고폭 화약의 양쪽 끝부분에서 방사되는 파편의 발사속도 구배 현상이 뚜렷이 나타났지만 법선 방향에 대한 발사각은 6° 이내로 나타났다. We have studied the numerical analysis about the fragment ejection velocity and spray angle when the High Explosive warhead detonated at proximity distance at an aircraft. To study the physical quantities about the warhead components is very important to assessment the vulnerability of aircraft. Generally, the physical quantities about the components of a warhead such as the mass, length, diameter and charge to mass ratio are unknown. Therefore, it is required to estimate the physical quantities by using physical continuities of similar threats. The empirical formulas to understand the dependence among charge to mass ratio, length and diameter ratio were driven by using the physical parameters of similar threatening such as terrier, sparrow. As a result, we confirmed that the dead mass ratio was closed to 20% of warhead mass since the metal case of the proximity threat acts as a simple carrier. This implies that the effective length and diameter of High Explosive Compound is smaller than the length and diameter of warhead, and become a key to understand the large ejection gradient velocity and small spray angle of fragments within 6 degree.
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