• Journal of Astronomy and Space Sciences
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• 제27권3호
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• pp.189-194
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• 2010

In this paper we have investigated latitudinal variations of the poleward boundary of the nightside auroral oval when the magnetosphere is hit by an enhanced solar wind dynamic pressure front. We used precipitating particle data obtained from Defense Meteorological Satellite Program satellites to identify the locations of the boundary before and after enhanced pressure impacts. The boundary locations are represented by a parameter called "b5e". After performing the analysis for a number of events, we found that the basic effect of the solar wind pressure increase impact is often (but not always) to move the poleward boundary of the nightside auroral oval poleward. However, this effect can be often modified by other factors, such as simultaneous variations of the interplanetary magnetic field with a pressure increase, and thus the boundary response is not necessarily a poleward shift in many cases. We demonstrate this with specific examples, and discuss other possible complicating factors.

• Journal of the Korea Institute of Information and Communication Engineering
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• 제20권8호
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• pp.1607-1614
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• 2016

Because required weapon systems in the planning stage exceed the extent of defense budget, we should consider the priorities of them in the programming and budget stage. The purpose of this paper is to find out the factors that affect the prioritization of required weapon systems limited by budget. For this purpose, we analyse statistically major 20 defense projects launched in 2014. We derived the reasons for prioritization through the pairwise comparisons and also extracted six representative factors through the Exploratory Factor Analysis(EFA). The KMO was 0.779 and the total variance explained was 79.59%, Cronbach's Alpha was above 0.7 which means EFA was appropriate to accept. The significance of this paper is that influencing factors on prioritization was derived by the comparisons using the present weapon systems and people in charge of defense acquisition. The factors can be utilized in AHP or Delphi to determine the priority and ultimately contribute to rational judgement for the military strategy objectives within the limited resources.

• International Journal of Naval Architecture and Ocean Engineering
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• 제4권1호
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• pp.9-19
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• 2012

A set of equations of motion is derived for vibratory motions of an underwater cable connected to a moving vehicle at one end and with drogues at the other end. From the static analysis, cable configurations are obtained for different vehicle speeds and towing pretensions are determined by fluid resistance of drogues. Also the dynamic analysis is required to predict its vibratory motion. Nonlinear fluid drag forces greatly influence the dynamic tension. In this study, a numerical analysis program was developed to find out the characteristic of cable behaviour. The motion is described in terms of space and time coordinates based on Chebyshev polynomial expansions. For the spatial integration the collocation method is employed and the Newmark method is applied for the time integration. Dynamic tensions, displacements, velocities, accelerations were predicted in the time domain while natural frequencies and transfer functions were obtained in the frequency domain.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제16권5호
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• pp.3199-3209
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• 2015

The importance of offset program has been increased, recently. Most research focused on the technology valuation and improvement of offset program. Research related with assessment of offset companies and development of differentiated strategies for cultivating them although they are important actor in offset program. Hence, this paper aims to propose the framework for assessing offset companies and providing the differentiated strategies using Desirability Function and IPA. Additionally, by applying the proposed framework to real offset companies, the applicability and usefulness of it are verified. The framework consists of extracting performance measures, assessment of it using Desirability Function and AHP and strategic planning based on IPA.

• Journal of the Korea Institute of Military Science and Technology
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• 제19권4호
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• pp.483-491
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• 2016

A simple aerodynamic calculation program for high Mach number flow is developed by combining the modified Newtonian method with Tannehill's curve fits for the thermodynamic properties of air in equilibrium state. Aerodynamic characteristics for a parabolic nose are predicted and compared with CFD(Computational Fluid Dynamics) analysis results. Comparison shows good agreements, and the developed program is expected to be a practical tool for slender body aerodynamic calculation for high Mach number flow.

• Journal of the Korean Society of Combustion
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• 제20권3호
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• pp.27-34
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• 2015

The objective of the current study is to introduce detailed process for a preliminary combustor design, and to develop a computer code for it. The program includes various empirical and semi-empirical methodologies for diffuser deign, combustor sizing, air distribution, and sub-component design such as primary and secondary zones. Using the developed program, the combustor sizing results are shown from an assumption of simple annual combustor cycle analysis. Two options are employed, 1) pressure loss approach, and 2) velocity assumption approach. Design results show that there are no significant differences in combustor sizing between two design options. Further code improvement is required for performance and emission evaluations of the designed combustor.

• Journal of Information Technology Services
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• 제11권sup호
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• pp.1-16
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• 2012

Information technology is a useful strategic weapon that can create competitive advantage and new business opportunity by applying it in the organization' value chain. IT convergence can be understood as an attempt of industrial level IT adoption to facilitate the innovation of the industry and the birth of a new industry. This study provides the comprehensive review of the Korean government' three IT assimilation programs, ubiquitous technology diffusion program of the Ministry of Knowledge Economy, u-service program of the Ministry of Public Administration and Security, and u-Defence cooperation program of the Department of Defense. The analysis is done through the interpretation of the existing literature and the logic model. The result proposes inter-agency cooperation and building of new technology road-map in the planning stage, flexible management in the execution phase, and failure tolerant evaluation system. The proposal for developing competencies and institutional foundations for IT convergence also presented.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• 제42권8호
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• pp.683-691
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• 2014

Significance of SAR(Synthetic Aperture Radar) satellite regadless of weather have grown for Earth observation. According to the cost-effective trend in satellite development, SAR antenna is actively studied. It's a competitive candidate to use deployable SAR antenna out of CFRP. In this study, variables for an antenna configuration model was researched and evaluated. The design of the antenna was structurally analyzed by FEM(Finite Element Model). Tool-kit was developed for modifying the SAR antenna model easily in accordance with system requirement change. In the tool-kit, antenna configuration design and error analysis of the antenna surface could be achieved. And compatibility of tool-kit results to CST, a RF analysis program, was confirmed.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제15권5호
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• pp.2579-2586
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• 2014

It is crucial to set up early the required performance of surface ship for preventing the risk factors such as an excess of performance, cost and period in development stage. In this study, MOP and MOE are proposed to establish the method for deriving alternatives, MOP represents the defensive effect for anti ship missiles and MOE is the ratio of cost and performance. The 16 engagement scenarios which selectively install RF decoy, RF jammer, CIWS and anti air missile are suggested. The simulation results by using NORAM tool operated by ROK Navy show that the ship survivability is 0.605~0.975 and MOP is 0.301~0.887. The analyzed results represent the operating scenario with RF decoy, RF jammer and short range anti air missile is the best cost and effectiveness measure.

• Journal of Multimedia Information System
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• 제7권1호
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• pp.55-72
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• 2020

As the IT service environment grows, it is critical in terms of IT service quality to minimize the occurrence of failures due to changes in applications and to diagnose and recover in a short period of time how failure will affect the business. Thus, the Defense Acquisition Program Administration (DAPA) has been building and operating ITSMs to implement IT service management in a leading manner. Information Technology Service Management (ITSM) is divided into events, obstacles, changes, versions and setup management to ensure flexibility and stability in service delivery. It is also operated separately from service level, availability, capacity, financial and IT service continuity management to ensure service quality and cost efficiency. Based on ITSM military service history, this study looks at the impact of quality of service on value, satisfaction, and trust. The results of the analysis are highly valuable for future ITSM implementation and operation.