• Journal of the Society of Cosmetic Scientists of Korea
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• v.22 no.1
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• pp.27-39
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• 1996

Recently, in vitro stratum curneum model was a useful tool to evaluate the skin condition such as tranespidermal water loss, skin hydration and etc.. In this study to evaluate the alteration of SC with aging in hairless mouse, we measured TEWL using in vitro SC model, SC lipid, and outer corneocytes area. Although the total SC lipid was rich about 30% in 8 week old mouse compared with that of 82 week old mouse, the TEWL values were higher in the former than that of the latter. The outer corneocytes area was 559 $\pm$ 65 $mu extrm{m}$2 in 8 week old mouse and 755 $\pm$ 56 ${\mu}{\textrm}{m}$2 in 82 week old mouse. So the barrier function was reinforced with aging. This result suggested that the reinforced barrier function is one of the defense systems against the outer enviornment and the decreased skin function with aging.

• Journal of computational fluids engineering
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• v.19 no.2
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• pp.17-23
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• 2014

Cavitation causes a great deal of noise, damage to components, vibrations, and a loss of efficiency in devices, such as propellers, pump impellers, nozzles, injectors, torpedoes, etc. Thus, the cavitating flow simulation is of practical importance for many engineering systems. In the present work, a two-phase flow solver based on the homogeneous mixture model has been developed. The solver employs an implicit preconditioning, dual time stepping algorithm in curvilinear coordinates. The flow characteristics around Clark-Y hydrofoil were calculated and then validated by comparing with the experimental data. The lift and drag coefficients with changes of angle of attack and cavitation number were obtained. The results show that cavity length and lift, drag coefficient increase with increasing angle of attack.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.1
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• pp.79-86
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• 2007

The Magnus effect measurement apparatus was designed and built for spinning wind tunnel model which would simulate the rotation of projectiles. Prior to the high speed test, the ground functional test and the low speed test were carried out in the Agency for Defense Development's Low Speed Wind Tunnel(ADD-LSWT) at spin rates from about 6,000 to 10,000 rpm. Magnus force and moment were measured on the spinning projectile model at velocity of 100 m/s. It was shown that the Magnus force and moment were linear function of spin parameter. The test results were compared with Magnus test run on the same configuration in the Arnold Engineering Development Center's Propulsion Tunnel 4T(AEDC-4T).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.11
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• pp.5442-5447
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• 2013

This paper focuses on development of SCAAM(Ship Collision Avoidance Assignment Model) for avoiding ship collison at sea. We take a new look at DCPA, TCPA, VCD, collision concept for ship collision avoidance and propose SCAAM using DCPA pre-assignmented by a ship master on information collected by other ship's AIS, GPS (course-speed, destination, length, width, tonnage etc). If A ship is a collision situation, the ship master makes a decision where the ship makes a evasion voyage or not continually using SCCAM. If ship master decides a evasion voyage, the ship is voyaged by CORLEGS (International Regulations for Preventing Collisions at Sea). This paper contributes to safety navigation by decreasing the ship collision accident by human's error.

• Journal of Korean Society for Quality Management
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• v.43 no.3
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• pp.221-238
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• 2015

Purpose: In this study, A reliability assurance model (or reliability program) is proposed to evaluate the reliability of an armed vehicle. The reliability assurance is performed through the reliability-centered activities during its life cycle of development/design, production, deployment, maintenance, and disposal. Methods: By reflecting the current situations of korea defense industry, a reliability assurance model is built up based on the benchmarking results of world leading companies' best practices in same fields. Results: The proposed reliability program of armed vehicles, which is based on the reliability program of ANSI/GEIA-STD 0009, uses DMAIC process of the six sigma methodology from design phase to testing and evaluation phase. Conclusion: This research is supposed to develop reliability program of armed vehicles by integrating DFSS, DFR and reliability growth process.

• Tunnel and Underground Space
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• v.27 no.4
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• pp.185-194
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• 2017

This technical paper is a study on the unique displacements of Shotcrete Lining at the mined tunnel during excavation period through deep consideration with real time data from monitoring instrumentations correlation with the numerical analysis to identify the rock stresses and the rock spring points at the working face of the Conventional tunnelling by the Drill and Blast, based on the geological face mapping results of the project NS2, Transmission cable tunnel project in Singapore. The created geometry of numerical model was prepared to the real mined tunnel construction site including, vertical shaft, construction adit, tunnel junction area, and 2 enlargement caverns. The convergence measurements by the monitoring instrumentation were performed during the tunnel excavation and shaft sinking construction stages to guarantee the safety of complicated underground structures.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.11
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• pp.5455-5475
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• 2016

In this article, we model the distributed relay assignment network as a many-to-one matching market with peer effects. We discuss two scenarios for throughput optimization of relay networks: the scenario of aggregate throughput optimization and the scenario of fairness performance optimization. For the first scenario, we propose a Mutual Benefit-based Deferred Acceptance (MBDA) algorithm to increase the aggregate network throughput. For the second scenario, instead of using the alternative matching scheme, a non-substitution matching algorithm (NSA) is designed to solve the fairness problem. The NSA improves the fairness performance. We prove that both two algorithms converge to a globally stable matching, and discuss the practical implementation. Simulation results show that the performance of MBDA algorithm outperforms existing schemes and is almost the same with the optimal solution in terms of aggregate throughput. Meanwhile, the proposed NSA improves fairness as the scale of the relay network expands.

• International Journal of Aeronautical and Space Sciences
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• v.16 no.1
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• pp.50-63
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• 2015

Explosive bolts are one of pyrotechnic release devices, which are highly reliable and efficient for a built-in release. Among them, ridge-cut explosive bolts which utilize shock wave generated by detonation to separate bolt body produce minimal fragments, little swelling and clean breaks. In this study, separation phenomena of ridge-cut explosive bolts or ridge-cut mechanism are computationally analyzed using Hydrocodes. To analyze separation mechanism of ridge-cut explosive bolts, fluid-structure interactions with complex material modeling are essential. For modeling of high explosives (RDX and PETN), Euler elements with Jones-Wilkins-Lee E.O.S. are utilized. For Lagrange elements of bolt body structures, shock E.O.S., Johnson-Cook strength model, and principal stress failure criteria are used. From the computational analysis of the author's explosive bolt model, computational analysis framework is verified and perfected with tuned failure criteria. Practical design improvements are also suggested based on a parametric study. Some design parameters, such as explosive weights, ridge angle, and ridge position, are chosen that might affect the separation reliability; and analysis is carried out for several designs. The results of this study provide useful information to avoid unnecessary separation experiments related with design parameters.

• Convergence Security Journal
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• v.15 no.6_1
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• pp.49-57
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• 2015

Changes in the national intelligence security industry is becoming increasingly rapidly changing due to the development of the network and the use of the Internet. Information also can be called by critical information assets, as well as social infrastructure of the country's reality is that individuals at risk. These professionals make to prevent terrorists to destroy national defense system and network was absolutely necessary. But, Cyber Terror Response NCOs to be responsible for cyber terrorism requires a professional NCOs with advanced knowledge. National Competency Standards(NCS) using a national information security field tutors to conduct training courses teaching - learning model to develop and to apply.

• Korean Journal of Computational Design and Engineering
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• v.19 no.3
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• pp.253-262
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• 2014

3D city model, which consisted of the 3D building models and their geospatial position and orientation, is becoming a valuable resource in virtual reality, navigation systems, civil engineering, etc. The purpose of this research is to propose the new framework to generate the 3D city model that satisfies visual and physical requirements in ground oriented simulation system. At the same time, the framework should meet the demand of the automatic creation and cost-effectiveness, which facilitates the usability of the proposed approach. To do that, I suggest the framework that leverages the mobile mapping system which automatically gathers high resolution images and supplement sensor information like position and direction of the image. And to resolve the problem from the sensor noise and a large number of the occlusions, the fusion of digital map data will be used. This paper describes the overall framework with major process and the recommended or demanded techniques for each processing step.