The Multiple Traveling Purchaser Problem for Minimizing the Maximal Acquisition Completion Time in Wartime

최명진,문우범,최진호,Choi, Myung-Jin,Moon, Woo-Bum,Choi, Jin-Ho The Korea Institute of Military Science and Techno 2011 한국군사과학기술학회지 Vol.14 No.3

In war time, minimizing the logistics response time for supporting military operations is strongly needed. In this paper, i propose the mathematical formulation for minimizing the maximal acquisition completion time in wartime or during a state of emergency. The main structure of this formulation is based on the traveling purchaser problem (TPP), which is a generalized form of the well-known traveling salesman problem (TSP). In the case of the general TPP, an objective function is to minimize the sum of the traveling cost and the purchase cost. However, in this study, the objective function is to minimize the traveling cost only. That's why it's more important to minimize the traveling cost (time or distance) than the purchase cost in wartime or in a state of emergency. I generate a specific instance and find out the optimal solution of this instance by using ILOG OPL STUDIO (CPLEX version 11.1).

감마선 검출용 $HgI_2$ 소자 제작 및 특성 평가

최명진,이홍규,강영일,임호진,최승기,Choi, Myung-Jin,Lee, Hong-Kyu,Kang, Young-Il,Lim, Ho-Jin,Choi, Seung-Ki 대한방사선방어학회 1991 방사선방어학회지 Vol.16 No.2

상온에서 사용할 수 있는 감마선 검출 소자로서 $HgI_2$ 소자의 응용성을 판단하기 위하여 기상 성장법으로 $HgI_2$ 단결정을 성장시켰고 이를 이용하여 검출 소자를 제작한 후 감마선 검출 특성을 조사하였다 성장된 단결정의 비저항과 전하 운반자 포획 밀도는 상온에서 각각 $10^{11}{\Omega}\;cm$와 $1.8{\times}10^{14}/cm^3$였으며 단결정의 Photoluminescence를 측정한 결과 성장된 $HgI_2$ 단결정의 밴드갭의 온도계수는 20K부터 77K에서 $-1.53{\times}10^{-4}eV/K$였다. 감마선 검출실험 결과 제작된 $HgI_2$ 검출 소자는 상온에서 우수한 계수 특성과 시간에 대한 선형적 축적 계수 특성을 나타내었으나 온도변화에 따라 계수의 특성의 변화는 심하였다. The $HgI_2$ single crystal which can be used for the ${\gamma}-ray$ detector at room temperature was grown by Temperature Oscillation Method. The low temperature photoluminescence, specific resistivity and trap concentration of $HgI_2$ single crystal were investigated. Three main luminescence bands were observed at 2.30eV, 2.20eV and 2.00eV at 20K, related to the excitons, I-vacancies and impurities, respectively. The specific resistivity and trap concentration of $HgI_2$ single crystal were $10^{11}{\Omega}\;cm\;and\;1.8{\times}10^{14}/cm^3$ at room temperature, respectively. Also the radiation detecting system was deviced by $HgI_2$ ${\gamma}-ray$ detector, one chip microprocessor, LCD module and personal computer. The prepared $HgI_2$ ${\gamma}-ray$ detector showed a good linearity of ${\gamma}-radiation$ dose for standard ${\gamma}-ray$.

캠축의 구조 진동 응답 및 응력

최명진,Choi, Myung-Jin 한국음향학회 2013 韓國音響學會誌 Vol.32 No.3

캠축의 진동 응답을 구하기 위해 캠축을 불균형 다단계 로터 베어링계로 해석하였으며, 복잡한 형상과 하중조건을 고려하여 유한요소법을 사용하였다. 유한요소 방정식을 유도한 후에 Newmark 법을 사용하여 진동 응답을 구하였다. V-8 엔진 캠축의 회전 진동 응답을 구하여 측정치와 비교하였다. 캠축의 변동 응력을 구하고, 응력 집중 효과를 고려한 다음에 Goodmann 식에 근거하여 피로 해석을 수행하였다. 캠축의 회전 진동에서는 굽힘 효과가 지배적이며, 인접하는 베어링 간격에 가장 큰 영향을 받는다. 캠축에 가해지는 하중의 변화가 클 경우에는 하중의 변화에 상응하여 시간에 따라 변화하는 베어링 계수를 적용하여야 함을 알 수 있었다. To get vibration responses, a camshaft is modelled as an unbalanced multiple rotor bearing system. Because of complex geometry and complicated load conditions, the finite element method is used. After the finite element equation of the system is constructed, Newmark's method is used to get the vibration responses. Whirl vibration responses of a V-8 engine camshaft are estimated and compared with measured responses. After the fluctuating stresses are obtained, fatigue analysis is performed based upon the modified Goodman's equation. Stress concentration effects are considered. In the whirl vibration of camshafts, the bending effect is dominant, and the bending deformation is dependent upon the span length between the adjacent bearing journals. For high speeds, the fluctuations of excitation forces are large, and it is known that nonlinear time varying bearing coefficients should be used for analysis.

고 비저항 p - Cd80Zn20Te 의 저항성 전극형성에 관한 연구

최명진,왕진석 ( Myung Jin Choi,Jin Suk Wang ) 한국전기전자재료학회 1997 한국전기전자재료학회 춘계학술대회논문집 Vol.1997 No.0

다차원선호도분석을 이용한 화력분야 방위산업기반 분석

최명진,이상헌,Choi, Myung-Jin,Lee, Sang-Heon 한국군사과학기술학회 2010 한국군사과학기술학회지 Vol.13 No.1

MDPREF(Multidimensional Preference Analysis) is a program for analysis of preferences. It is what is known as a vector model. This means that the objective of the MDPREF analysis is to identify a perceptual map displaying subject(attribute) vectors. To form the subject vectors visually, lines are drawn from the origin of the plot to each subject point. We analysis the defense industry infrastructure in fire power area by using MDPREF.

극대화된 밴드갭을 갖는 켈빈 격자 구조의 아이소-지오메트릭 최적 설계

최명진,오명훈,조선호,구본용,Choi, Myung-Jin,Oh, Myung-Hoon,Cho, Seonho,Koo, Bonyong 한국전산구조공학회 2019 한국전산구조공학회논문집 Vol.32 No.4

밴드갭은 기계적 파동의 전파가 금지되는 특정 주파수 범위를 의미한다. 본 연구는 경사도 기반의 설계 최적화 방법을 사용하여 낮은 가청 주파수 범위에서 밴드갭을 갖는 3차원 켈빈 격자를 설계하는 것을 목적으로 하고 있다. 블로흐 이론을 이용하여 무한주기 격자에서의 탄성파 전파를 해석하고, 기하학적으로 엄밀한 빔 이론에서 선형화를 통해 얻은 전단 변형 가능한 빔 모델을 사용하여 격자 구조 연결선을 모델링하였다. 주어진 격자 구성에서 중립 축 및 단면 두께를 B-spline 함수를 이용한 아이소-지오메트릭 매개화를 통해 설계 변수로 정의하고, 격자 구조의 밴드갭의 크기를 극대화하는 최적 설계를 수행하였다. A band gap refers to a certain frequency range where the propagation of mechanical waves is prohibited. This work focuses on engineering three-dimensional Kelvin lattices having external band gaps at low audible frequency ranges using a gradient-based design optimization method. Elastic wave propagation in an infinite periodic lattice is investigated by employing the Bloch theorem. We model the ligaments using a shear-deformable beam model obtained by consistent linearization in a geometrically exact beam theory. For a given lattice topology, we enlarge band gap sizes by controlling the configuration of the beam neutral axis and cross-section thickness that are smoothly parameterized by B-spline basis functions within the isogeometric analysis framework.

전시 군수반응시간 최소화를 위한 복수 순회구매자 문제

최명진,Choi, Myung-Jin 한국군사과학기술학회 2010 한국군사과학기술학회지 Vol.13 No.3

It's strongly needed to minimize the logistics response time for supporting military operations in wartime. In this paper, we suggest the ILP formulation for minimizing logistics response time in wartime. Main structure of this formulation is based on the traveling purchaser problem(TPP) which is a generalized form of the well-known traveling salesman problem(TSP). In the case of general TPP, objective function is to minimize the sum of traveling cost and purchase cost. But, in this study, objective function is to minimize traveling cost only. That's why it's more important to minimize traveling cost(time or distance) than purchase cost in wartime. We find out optimal solution of this problem by using ILOG OPL STUDIO(CPLEX v.11.1) and do the sensitive analysis about computing time according to number of operated vehicles.

발효 옻 추출물의 생리활성 및 단회 경구 투여 독성시험

최명진,이승진,장승희,홍주헌,정희경,박승춘,Choi, Myung-Jin,Lee, Seung-Jin,Jang, Seung-Hee,Reza, Md. Ahsanur,Hong, Joo-Heon,Jung, Hee-Kyoun,Park, Seung-Chun 대한수의학회 2010 大韓獸醫學會誌 Vol.50 No.3

In this study, we investigated the biological activities such as anti-tumor, anti-oxidant and antiinflammatory activities as well as single oral dose toxicity of fermented Rhus verniciflua extract (FRVE). In order to examine anti-tumor activity of FRVE, the sarcoma 180 cells were treated with FRVE at various concentrations (0.03, 0.3, 3 and 30 mg/mL) in microtetrazolium (MTT) assay. In MTT assay, all the cells treated with FRVE at various concentrations have shown a significant difference compared with control (p < 0.05). In xanthine oxidase inhibition assay to examine the antioxidant activity, the xanthine oxidase inhibition rate of FRVE at 1.5 mg/mL and 15 mg/mL was $85{\pm}15.01%$ and $99{\pm}16.02%$, respectively. Nitric oxide production in RAW 264.7 cells showed that FRVE showed a significant anti-inflammation effect at 3 mg/mL (p < 0.05). In single oral dose toxicity study, no differences were observed between control and treated groups in clinical signs, body weight gains, feed and water consumptions. The results indicated that lethal dose 50 ($LD_{50}$) of FRVE was found to be higher than 5,000 mg/kg in this experiment. From the above results, we may suggest that FRVE might have useful as a material for functional food and/or animal pharmaceutics.

국방연구개발사업 수행위험 측정방안 연구

최명진,나호영,이상헌,Choi, Myung-Jin,Na, Ho-Young,Lee, Sang-Heon 한국군사과학기술학회 2009 한국군사과학기술학회지 Vol.12 No.3

The risk management is a method to identify and to handle risk factors. In this paper, we introduce a methodology that can be used to measure of system's performance risk by combining system's TPM(technical performance measures) in the R&D(research and development) program for defense acquisition. By applying the suggested procedure, we can monitor risk trends in R&D program by calculation of system's overall TPM and find out where management should target to reduce or remove the system's performance risk.

아이소-지오메트릭 형상 최적설계의 실험적 검증

최명진,윤민호,조선호,Choi, Myung-Jin,Yoon, Min-Ho,Cho, Seonho 한국전산구조공학회 2014 한국전산구조공학회논문집 Vol.27 No.5

본 논문에서는 아이소-지오메트릭 형상 최적설계 기법에서 얻은 CAD 정보를 직접 활용하여, 3D 프린터를 활용한 실험적 검증을 위한 시편을 제작하였다. 유한요소법에서는 요소망에 내재하는 기하학적인 근사가 응답과 설계민감도 해석에서 정밀도 문제를 발생시킨다. 더욱이 유한요소 기반 형상 최적화 과정에서는 CAD와의 정보교환이 필수적이나 그 과정에서 최적설계 정보의 손실이 발생할 수 있다. 아이소-지오메트릭 기법은 CAD에서 사용된 동일한 NURBS 기저함수와 조정점을 사용하므로 법선벡터와 곡률과 같은 엄밀한 기하학적 정보를 응답해석과 설계민감도 해석에 사용할 수 있다. 또한 최적설계 과정에서 CAD와 정보교환 없이 복잡한 형상을 손쉽게 변경할 수 있다. 그러므로 최적의 설계의 재료량을 실험적 검증을 위한 시편제작에 엄밀하게 반영할 수 있다. 굽힘 하중을 받는 단순지지 구조물에 대한 최적설계 및 실험적 검증을 통해 최적형상이 초기 형상에 비해 더 큰 강성을 가지며 실험결과와 수치 해석결과가 매우 잘 일치함을 보였다. 또한 인장력을 받는 유공판에 대한 형상 최적설계를 수행하였으며, 비접촉식 3차원 변형 측정 장치를 이용하여 초기설계에 비해 최적설계에서 구멍주변에서의 응력집중 현상이 완화됨을 확인하였다. 따라서 수치적인 방법을 활용한 최적설계가 실제 구조물에 대한 실험에서도 유효함을 입증하였다고 할 수 있다. 또한, 아이소-지오메트릭 최적설계 방법론이 기존의 유한요소법에 비해서 최적설계 결과를 제작하여 활용하는데 있어서도 훨씬 효율적이고 엄밀한 방법임을 보였다. In this paper, the CAD data for the optimal shape design obtained by isogeometric shape optimization is directly used to fabricate the specimen by using 3D printer for the experimental validation. In a conventional finite element method, the geometric approximation inherent in the mesh leads to the accuracy issue in response analysis and design sensitivity analysis. Furthermore, in the finite element based shape optimization, subsequent communication with CAD description is required in the design optimization process, which results in the loss of optimal design information during the communication. Isogeometric analysis method employs the same NURBS basis functions and control points used in CAD systems, which enables to use exact geometrical properties like normal vector and curvature information in the response analysis and design sensitivity analysis procedure. Also, it vastly simplify the design modification of complex geometries without communicating with the CAD description of geometry during design optimization process. Therefore, the information of optimal design and material volume is exactly reflected to fabricate the specimen for experimental validation. Through the design optimization examples of elasticity problem, it is experimentally shown that the optimal design has higher stiffness than the initial design. Also, the experimental results match very well with the numerical results. Using a non-contact optical 3D deformation measuring system for strain distribution, it is shown that the stress concentration is significantly alleviated in the optimal design compared with the initial design.