• Journal of the Korea Institute of Military Science and Technology
• /
• v.19 no.3
• /
• pp.311-318
• /
• 2016

This paper shows storage life estimation of next IR(infrared) flare material through accelerated degradation tests. Three temperature conditions for the accelerated degradation tests are 55, 65 and $75^{\circ}C$. Six performances of IR flare material are burning time, IR peak/continuous Intensity, total energy of near/mid-IR and color ratio, and they were measured after the tests. Storage life of the IR flare material was estimated through both analyzing the degradation data of those performances and applying distribution-based degradation models to the data. Over 30 years of storage life at $20^{\circ}C$ is estimated in terms of IR peak intensity with reliability 0.99 and confidence level 99 %. Additionally, 10 years of storage period at $21^{\circ}C$ would be equivalent to 68 days of accelerated test at $65^{\circ}C$ from the activation energy in Arrhenius model.

• Journal of Ocean Engineering and Technology
• /
• v.27 no.3
• /
• pp.36-42
• /
• 2013

According to a study on improving ship survivability, an IR signature represents the contrast radiance intensity between the radiation signature from a ship and the background signature. It was found from applying stealth techniques to the process of ship development that the IR signature is remarkably sensitive and dependent on the environment. In this study, marine climate data for the sea near the Korean Peninsula were collected, and the marine meteorological environment in Korean waters was defined. Based on this data, a study on the sensitivity of the IR signature of target objects was performed using analytical methods. The results of the research indicated that clouds have important effects on the infrared signature, but the velocity of the wind and the humidity have only slight effects on the IR signature. In addition, the air and seawater temperatures had hardly any effect on the IR signature, but it is judged that additional study is needed.

• The Journal of Korean Physical Therapy
• /
• v.12 no.3
• /
• pp.469-474
• /
• 2000

This studies were to investigate the effects of low power intensity Helium-Neon Infra-Red(He-Ne IR) laser on the changes of the serum immunoglobulin(1g) components in burn rats, The fourty eight Spraque-Dawley adult male rats were assigned to the 8 groups: the experimental groups(4), the burn control groups(2) and the control groups(2) There was made three degree burn by the 250mW IR on the back of each rats, from 3 days after being burned, the experimental laser groups were irradiated low power He-Ne IR laser for 3 minutes and 4.5 minutes every day during the 7days and 21 days. The results were as follows: The concentrations of immunoglobulin G(Ig G) in serum of burn rats on the treated with during the 3minutes laser for 7 days were higher than those of burn and 4.5 minutes laser groups. There were significantly decreased the change of the level of immunoglobulin M(Ig M) in serum of burn rats on the treated with 3 minutes laser for 7 days to the control group, but were significantly increased on the 3minutes and 4.5 minutes laser groups for 21 days to the those of burn and control groups, and the levels of the Ig M on the 3minutes laser group for 21 days were higher than those of 7 days. The concentrations of immunoglobulin E(Ig E) in serun of the burn rats on the experimental and burn groups were significantly lower than those in control group. As above results, The changes of the level of immonoglobulin components in serum have meaningful role in the healing process on the treated with the low pewer intensity of HE-Ne IR laser.

• Journal of the Society of Naval Architects of Korea
• /
• v.50 no.3
• /
• pp.182-189
• /
• 2013

In the development process of new naval ships, it is necessary to make the effort of the signature management and reduction of ship infrared(IR) signature to increase the ship survivability(susceptibility). So far the ship's contrast radiant intensity is used as a ship IR signature design criteria during the naval ship design stages. However, nowaday it is in a state of disorder at the basic design stage because of the lack of any related studies and methods. In this study, the IR signature management methods for improving the signature reduction and ship survivability are suggested by the comparison analysis of the advantages and disadvantages of signature management techniques. And also the criteria for the ship signature management are suggested when considering the infrared signature measuring assets and sea trial environments of the Korean peninsula.

• Journal of the Korean Wood Science and Technology
• /
• v.16 no.4
• /
• pp.3-9
• /
• 1988

Infrared (IR) spectroscopic techniques for the analysis of wood samples and the absorbance spectra of solid woods were presented. KBr pellets were prepared by throughly mixing approximately 300 mg of dried KBr and 1 mg of finely milled wood powder extracted with ethanol-cyclohexane previously. This mixture was made into a transparent disc by means of a pellet-making die (10 ton/$cm^2$ for 10 min). This IR techniques were applied for the analysis of archaeological wood samples. The most notable difference in the IR spectra between the recent and the archaeological waterlogged woods is that the absorption band centered at $1,730cm^{-1}$ was significantly diminished in the waterlogged ones. Total loss of absorption in $1,730cm^{-1}$ might be mainly due to the result of hemicellulose degradation. Another feature indicated by IR spectral comparision are that the degraded waterlogged wood samples showed 1) the increased intensity of the 1,600, 1,500 and $1,270cm^{-1}$ due to the residual lignin and the increased intensity at 1,470 and $1,425cm^{-1}$ due to the degradation of hemicellulose and 2) to the emergence of single band around $1,050cm^{-1}$ instead of three bands at 1,110, 1,060 and $1,040cm^{-1}$ in recent wood due to the degradation of cellulose crystalline. It was revealed from the IR examinations that the first change of wood in the waterlogged situation was the lysis of hemicellulose and the second the lysis of cellulose. It was also suggested that IR spectroscopy could serve a fast method for the investigation on the chemical characteristics of archaeological wood samples.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.38B no.9
• /
• pp.736-743
• /
• 2013

In IRST(infrared search and track) system, the small target detection is very difficult because the IR(infrared) image have various clutter and sensor noise. The noise and clutter similar to the target intensity value produce many false alarms. In this paper. We propose the adaptive detection method which obtains optimal target detection using the image intensity information and the prior information of target. In order to enhance the target, we apply the human visual system. we determine the adaptive threshold value using image intensity and distance measure in target enhancement image. The experimental results indicate that the proposed method can efficiently extract target region in various IR images.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.17 no.1
• /
• pp.108-114
• /
• 2014

This paper describes a method to set an intensity-based initial validation gate for tracking filter while preserves the ability of tracking a target with maximum speed. First, we collected real data set of signal versus distance of an airplane target. And at each data point, we computed maximum distance the target can move. And a function is modeled to expect the maximum moving pixels on the lateral direction based on the intensity of the detected target in IR image sequence. The initial prediction error covariance can be computed using this function to decide the size of the initial validation gate. The simulation results show the proposed method can set the appropriate initial validation gates to track the targets with the maximum speed.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2016.02a
• /
• pp.229.2-229.2
• /
• 2016

본 연구에서는 Host와 Dopant $Ir(ppy)_3$의 도핑 위치 변화에 따른 bottom emission 인광 OLED를 제작하여 발광 효율 및 특성을 분석하였다. 소자의 EML은 $Ir(ppy)_3/CBP$와 $CBP/Ir(ppy)_3$ 순으로 증착하여 제작하였다. $Ir(ppy)_3/CBP$은 낮은 구동 전압에서 큰 전류밀도와 큰 luminance을 측정하였고, 반대로 $CBP/Ir(ppy)_3$은 높은 구동 전압에서 $CBP/Ir(ppy)_3$은 큰 전류밀도와 큰 luminance가 측정되었다. 이는 $Ir(ppy)_3/CBP$에서 HTL과 EML 사이에 hole direct injection이 발생으로 Hole이 증가하지만 charge balance 불일치로 roll-off가 발생하고, $CBP/Ir(ppy)_3$에서 electron direct injection에 의한 electron 증가로 charge balance가 향상된다. EL spectrum 측정에서 $Ir(ppy)_3$은 파장 512nm 발광이 일어나고, CBP와 NPB은 각각 파장 380nm, 433nm로 분석된다. 각 물질의 triplet의 전달은 energy level이 큰 곳에서 작은 곳으로 전달되는데 이러한 이유로 전압에 따른 recombination zone 변화로 각 물질에서 나오는 파장의 intensity가 달라지는 것을 확인하였다. $Ir(ppy)_3/CBP$은 낮은 전류 밀도에서는 CBP의 영향으로 380nm 파장대가 크고, 높은 전류 밀도에서는 $Ir(ppy)_3$의 영향으로 512nm 파장대가 크게 나오는 것을 확인했고, $CBP/Ir(ppy)_3$에서는 낮은 전류 밀도에서 512nm 파장대가 커지고, 큰 전류 밀도에서는 CBP에서 NPB로의 triplet 에너지 전달의 증가로 433nm 파장대가 커지는 것을 확인하였다.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.42 no.8
• /
• pp.640-647
• /
• 2014

Infrared signature of aircraft exhaust plume is the critical factor for aircraft survivability. To improve the military aircraft survivability, the accurate prediction of infrared signature for the propulsion system is needed. The numerical analysis of thermal fluid field for nozzle inflow, free stream flow, and plume region is conducted by using the in-house code. Weighted Sum of Gray Gases Model based on Narrow Band with regrouping is adopted to calculate the spectral infrared signature emitted from aircraft exhaust plume. The accuracy and reliability of the developed code are validated in the one-dimensional band model. It is found that the infrared radiant intensity is relatively more strong in the plume through the analysis, the results show the different characteristic of the spectral infrared signature along the temperature, the partial pressure, and the species distribution. The continuous spectral radiant intensity is shown near the nozzle exit due to the emission from the nozzle wall.

• Membrane Journal
• /
• v.25 no.3
• /
• pp.268-275
• /
• 2015

Effects of aeration intensity on local fouling were investigated in submerged membrane modules. Higher liquid velocities were observed at the section with the lower fiber packing density. The liquid velocity is increased with increasing the gas-liquid injection factor. The high shear stress coincided with the high liquid velocity. The shear stress increases with the increasing of gas-liquid injection factor and the liquid velocity improves with the increasing of gas-liquid injection factor. Irreversible fouling resistance ($R_{ir}$) of the fiber position is significant in a local region of high suction pressure near the suction point of the fiber (position 1). The ratio of $R_{ir}/R_m$ and $R_{ir}/R_r$ of position 1 was highest compared to the position 2 and 3. Irreversible fouling resistances results confirmed the preferential deposition of foulants near the suction part of the fiber where the local suction pressure is the highest and correspondingly, more particles are accumulated to the membrane surface. The effects of local fouling along the fiber length are significant factors to optimize the design of submerged modules.