• International Journal of Aeronautical and Space Sciences
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• v.15 no.1
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• pp.102-111
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• 2014

An analytical model was developed to understand the physics and predict the functional performance of a pin puller. The formulated model is based on one-dimensional gas dynamics for an ideal gas. Resistive forces against pin shaft movement were measured in quasi-static mechanical tests, the results of which were incorporated into the model. The expansion chamber pressure and the pin shaft displacement were measured from an actual firing test and compared to the model prediction. The gas generation rate was adjusted by a correction factor, and the heat transfer rate was obtained through parametric analysis. The validity of the model is assessed for additional firing tests with different amounts of pyrotechnic charge. This model can provide knowledge on how the pin puller functions, and on which design parameters contribute the most to the actuation of the pin puller. Using this model, we estimate the functional safety factor by comparing the energy generated by the pyrotechnic charge to the energy required to accomplish the function.

• Journal of Information Technology Services
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• v.12 no.4
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• pp.77-90
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• 2013

As Cyber threats are rising, the scope of information Security (IS) is extending from technical protection of a single information system to organizational comprehensive IS capability. The ministry of National Defense (MND) has established the IS evaluation for defense organization in 'the Directive for Defense Informatization Affairs.' However, no information about an evaluation method, process and organization is provided. We surveyed information security management system (ISMS) and related best practices in public sector and other countries, and analysed the military information security affairs. Thus, this paper recommends the IS evaluation method and process. The trial IS evaluation is in progress this year and the MND will expand this IS evaluation to the entire organization.

• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.6
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• pp.117-126
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• 2008

Recently, the investment and importance have been increasing concerning the researches which are based on fundamental studies. In defense science and technology development, the defense research centers are involved in a large portion of developing the potential capability such as defense applied technology, enhanced human resource, etc. In this paper, we analyzed the relative efficiency of 9 research centers(9 DMU : Decision Making Unit) supported by the defense budget, using DEA(Date Envelopment Analysis) method especially with the CCR-I(Charnes, Cooper, Rhodes-Input) model. Some variables are selected such as budget(input data), patent, article and human resource(output data) to be analyzed. Conclusively, the needs to identify performance-indicators, increase incentives to promote the performance and induce enthusiastic participation in defense science and development projects, are suggested via a relative efficiency analysis.

• Knowledge Management Research
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• v.10 no.2
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• pp.65-84
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• 2009

The purpose of this study is to develop Meta Evaluation Indicators for Defense R&D Programs in Korea. At first, the four components of this meta evaluation model were designed, which are evaluation context, evaluation input, evaluation process and evaluation outcome. And fifty two indicators for this meta evaluation were developed by experts who performed evaluations for Defense R&D Programs. The reliability of components and items was verified by Cronbach's ${\alpha}$ coefficient. It was over 0.6 in all areas. The validity of components and items was verified by Factor Analysis. Analytic Hierarchy Process method was used in assigning the evaluation weight. The survey of twenty two evaluators participated in Defense R&D Programs showed that the Consistency Ratio was under 0.1 in evaluation components and items. In this study, an objective and reasonable set of Defense R&D Meta Evaluation Indicators was developed to increase the responsibility of Defense R&D Programs and improve the quality of evaluation results.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.31 no.1
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• pp.111-122
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• 2021

With the spread of technology in the 4th Industrial Revolution, the defense industry in South Korea is getting developed into an industrial structure in which high-tech technologies are concentrated. As the importance of defense technology has gradually increased, the government has enacted the Defense Technology Security Act and required to build a protection system for institutions that possess or manage defense technology. In order for the target institution to introduce a protection system, it is necessary to identify the defense technologies that are protected and to ensure systematic data management. In order to cope with this, we derived master data items for data management and analyzed the implementation types of defense technology master data system suitable for the defense industry environments. The derived method identified the defense technology master data, such as primary and secondary master data, and through AHP analysis, Co-existence type was suitable as the target model for the master data management system. We expect that stronger defense technology security policy will be implemented through the defense technology MDM system.

• Journal of the Korea Society for Simulation
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• v.9 no.4
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• pp.77-85
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• 2000

The object of this paper is developing of a simulation model for performance evaluation of ai defense-gun system. We developed a three-step kill probability of areal target in case of one gun on one target considering : 1) estimating the target and warhead intercept point, 2) target vulnerability and 3) computing the kill probability. We used a Monte Carlo simulation method. This model can be used for probabilistic analysis giving results of sufficient accuracy with minimum requirement of input data. Also we developed a computer program according proposed algorithm and a set of experimental results using the proposed method are shown.

• 한국전산유체공학회:학술대회논문집
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• 2003.10a
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• pp.166-166
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• 2003

• Korean Management Science Review
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• v.32 no.4
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• pp.109-133
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• 2015

This paper considers the allocation and engagement scheduling of air defense missiles by using MIP (mixed integer programming). Specifically, it focuses on developing a realistic MIP model for a real battle situation where multiple enemy missiles are headed toward valuable defended assets and there exist multiple air defense missiles to counteract the threats. In addition to the conventional objective such as the minimization of surviving target value, the maximization of total intercept altitude is introduced as a new objective. The intercept altitude of incoming missiles is important in order to minimize damages from debris of the intercepted missiles and moreover it can be critical if the enemy warhead contains an atomic or chemical bomb. The concept of so called the time window is used to model the engagement situation and a continuous time is assumed for flying times of the both missiles. Lastly, the model is extended to simulate the situation where the guidance radar, which guides a defense missile to its target, has the maximum guidance capacity. The initial mathematical model developed contains several non-linear constraints and a non-linear objective function. Hence, the linearization of those terms is performed before it is solved by a commercially available software. Then to thoroughly examine the MIP model, the model is empirically evaluated with several test problems. Specifically, the models with different objective functions are compared and several battle scenarios are generated to evaluate performance of the models including the extended one. The results indicate that the new model consistently presents better and more realistic results than the compared models.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.4
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• pp.253-259
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• 2017

Recent development in science and technology has modernized the weapon system of ROKN (Republic Of Korea Navy). Although the cost of purchasing, operating and maintaining the cutting-edge weapon systems has been increased significantly, the national defense expenditure is under a tight budget constraint. In order to maintain the availability of ships with low cost, we need accurate demand forecasts for spare parts. We attempted to find consumption pattern using data mining techniques. First we gathered a large amount of component consumption data through the DELIIS (Defense Logistics Intergrated Information System). Through data collection, we obtained 42 variables such as annual consumption quantity, ASL selection quantity, order-relase ratio. The objective variable is the quantity of spare parts purchased in f-year and MSE (Mean squared error) is used as the predictive power measure. To construct an optimal demand forecasting model, regression tree model, randomforest model, neural network model, and linear regression model were used as data mining techniques. The open software R was used for model construction. The results show that randomforest model is the best value of MSE. The important variables utilized in all models are consumption quantity, ASL selection quantity and order-release rate. The data related to the demand forecast of spare parts in the DELIIS was collected and the demand for the spare parts was estimated by using the data mining technique. Our approach shows improved performance in demand forecasting with higher accuracy then previous work. Also data mining can be used to identify variables that are related to demand forecasting.

• Journal of Electrical Engineering and Technology
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• v.6 no.2
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• pp.270-274
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• 2011

This paper presents a parameterized simulation program with integrated circuit emphasis (SPICE) model of a two-level microbolometer based on negative-temperature-coefficient thin films, such as vanadium oxide or amorphous silicon. The proposed modeling begins from the electric-thermal analogy and is realized on the SPICE modeling environment. The model consists of parametric components whose parameters are material properties and physical dimensions, and can be used for the fast design study, as well as for the co-design with the readout integrated circuit. The developed model was verified by comparing the obtained results with those from finite element method simulations for three design cases. The thermal conductance and the thermal capacity, key performance parameters of a microbolometer, showed the average difference of only 4.77% and 8.65%, respectively.