• Journal of the Korea Institute of Military Science and Technology
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• v.9 no.2 s.25
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• pp.34-41
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• 2006

This paper describes the general considerations and operational applications of aircraft night vision goggle(NVG). The operators should recognize the NVG characteristics, natural night light sources and interoperability between them. And they have to keep attention to the method to take steps to avoid misperceptions, illusions during flight, and the negative impact on the effectiveness and safety of the mission. The considerations based on the interoperability between NVG and night operation suggest the evaluation items of NVG field test and flight test.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2023.11a
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• pp.236-237
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• 2023

항공장애표시등은 항공기 운항에 위험을 초래할 수 있는 건물이나 구조물의 존재를 조종사에게 알리는 데 사용되는 등화이다. 본 논문은 조종사가 야간투시경(NVG)을 착용한 경우에도 식별이 가능한 적외선 LED 항공장애표시등의 개발 현황에 대해 연구하고자 한다.

• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.3
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• pp.51-61
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• 2007

This paper concerns about the requirement analysis for night vision imaging system(NVIS), whose purpose is to intensify the available nighttime near infrared(IR) radiation sufficiently to be caught by the human eyes on a miniature green phosphor screen. The requirements for NVIS are NVIS radiance(NR), chromaticity, daylight legibility/readability, etc. The NR is a quantitative measure of night vision goggle (NVG) compatibility of a light source as viewed through goggles. The chromaticity is the quality of a color as determined by its purity and dominant wavelength. The daylight legibility/readability is the degree at which words are readable based on appearance and a measure of an instrument's ability to display incremental changes in its output value. In this paper, the requirements of NR, chromaticity, and daylight legibility/readability for Type I and Class B/C NVIS are analyzed. Also the rationale is shown with respect to those requirements.

• Defense and Technology
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• no.8 s.294
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• pp.64-71
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• 2003

Rooivalk에 채택된 항전장착물은 프랑스의 Sextant가 주 개발자이며 3개의 다기능 디스플레이를 갖는 NVG 호환 G-Cockpit도 포함된다. Thales는 Topowl HMSD도 공급하는데 이것은 Denel사 Cumulus 공장에서 개발된 센서 터렛과 Pilkington Optronics와 공동개발한 Noctua PNVS와 연계된다. Rooivalk의 TDATS는 Topowl과 함께 작동하는 Cumulus사 Argos-780 EO 센서 터렛을 사용하고 있고 열상장비, TV카메라, 레이저 거리측정기, 레이저 표식기 그리고 자동추적기로 구성되어 있다.

• Nuclear Engineering and Technology
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• v.54 no.12
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• pp.4776-4797
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• 2022

In the one-dimensional thermal-hydraulic (TH) codes, a subcooled boiling model to predict the void fraction profiles in a vertical channel consists of wall heat flux partitioning, the vapor condensation rate, the bubbly-to-slug flow transition criterion, and drift-flux models. Model performance has been investigated in detail, and necessary refinements have been incorporated into the Safety and Performance Analysis Code (SPACE) developed by the Korean nuclear industry for the safety analysis of pressurized water reactors (PWRs). The necessary refinements to models related to pumping factor, net vapor generation (NVG), vapor condensation, and drift-flux velocity were investigated in this study. In particular, a new NVG empirical correlation was also developed using artificial neural network (ANN) techniques. Simulations of a series of subcooled flow boiling experiments at pressures ranging from 1 to 149.9 bar were performed with the refined SPACE code, and reasonable agreement with the experimental data for the void fraction in the vertical channel was obtained. From the root-mean-square (RMS) error analysis for the predicted void fraction in the subcooled boiling region, the results with the refined SPACE code produce the best predictions for the entire pressure range compared to those using the original SPACE and RELAP5 codes.

• Defense and Technology
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• no.9 s.247
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• pp.74-79
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• 1999

과거는 항공기의 야간임무 수행시 항법장비와 계기에 의존하여 작전을 수행하였다. 이것은 조종사로 하여금 비행 안정감을 주지 못하여 심리적 작전 저해요소로 작용하였다. 따라서, 야간 비행시에도 낮과 유사한 비행조건을 만들어주는 장비 즉, 야시장비체계 개발이 본격화 되었다. 야시장비가 장착된 항공기를 탑승하기 위해서는 야간 투시경(NVG)이 필요하며 항공기 내, 외부 조명의 개조가 전제되어야 한다. 이 글에서는 항공기 야시장비체계 개조의 필요성과 적용실례를 들어 야시장비체계에 대하여 소개하고자 한다.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.22 no.1
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• pp.145-151
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• 2014

Not only in Korea, but also in other countries, most helicopter accidents occur at low altitude. Analysis on accidents data collected both in Korea and other countries has brought two conclusions. Firstly, helicopter operations during the night hours carries a high risk. Secondly, the most common cause of night hour operations is loss of control due to the flight illusion. As an operation relying on a night vision in particular has a very high accident hazard, accompanying instruments such as NVG are ought to be provided. Hence, a thorough preparation and inspection on missions for night forest fire extinguishing should be required and perfect guidelines/road maps and enough training programs for the operation should be provided before the engagement in missions.

• Science of Emotion and Sensibility
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• v.19 no.1
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• pp.3-10
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• 2016

This research was to investigate the effect of fatigue reduction and heart rate recovery (HRR) according to whole body vibration (WBV). 20 healthy participants were recruited and divided into vibration group (VG) and none vibration group (NVG). VG was group with provided vibration and NVG was group without vibration. They exercised slope gait with 8.5 degree and 4km/h during 30min. They rested on the chair type vibrator during 30min. The vibration consists of 10hz as frequency and 5mm as amplitude. We measured the lactate in the blood and HRR before, immediately after exercise and after rest session. The results showed that lactate level in VG the more decreased at 95.2%. The result of HRR was similar including recovery at 50.67% in VG. The WBV with stimulated vessel in muscle assisted the recovery function by reducing the excess post-exercise oxygen consumption (EPOC) quickly and improving blood circulation. The rest with WBV could provide efficient cool-down exercise for elderly and women without other physical activities after exercise.

• Journal of Advanced Navigation Technology
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• v.14 no.5
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• pp.604-609
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• 2010

The tactical datalink system has been recognized as the key element in Network Centric Warfaret(NCW). The military has been putting great efforts into establishing datalink system using existing tactical radio and UMPC. but the aircraft operational environment and the requirement specification for equipments mounted in the avionics are differentiated with those in other platforms, so special efforts are needed to select suitable UMPC. In this paper, we consider the requirement analysis for UMPC in respect of processor performance, operation system (OS) and NVG compatibility. Additionally we have to make a effort to understand the operational environment of aircraft and examine th standard to select the appropriate UMPC, and then we expect to establish the tactical datalink system successfully.

• Nuclear Engineering and Technology
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• v.51 no.4
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• pp.977-986
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• 2019

In the thermal-hydraulic system codes, such as MARS and RELAP5/MOD3, the Savannah River Laboratory (SRL) model has been adopted as a subcooled boiling model. It, however, has been shown that the SRL model cannot take into account appropriately the effects of inlet liquid velocity and hydraulic diameter on axial void fraction development. To overcome the problems, Ha et al. (2018) proposed a modified SRL model, which is applicable to low-pressure and low-Pe conditions (P < 9.83 bar and $Pe{\leq}70,000$) only. In this work, the authors extended the modified SRL model by proposing a new net vapor generation (NVG) model and a wall evaporation model so that the new subcooled boiling model can cover a wide range of thermal-hydraulic conditions with pressures ranging from 1.1 to 69 bar, heat fluxes of $97-1186kW/m^2$, Pe of 3600 to 329,000, and hydraulic diameters of 5-25.5 mm. The new model was implemented in the MARS code and has been assessed using various subcooled boiling experimental data. The results of the new model showed better agreements with measured void fraction data, especially at low-pressure conditions.