Various types of optical materials and devices used in special environments must satisfy durability and optical properties. In order to improve the durability of zinc sulfide multispectral (MS ZnS) substrates with transmission wavelengths from visible to infrared, Ge-Sb-Se-based chalcogenide glass was used as a sealing material to bond the MS ZnS substrates. Wetting tests of the Ge-Sb-Se-based chalcogenide glass were conducted to analyze flowability as a function of temperature, by considering the glass transition temperature (Tg) and softening temperature (Ts). In the wetting test, the viscous flow of the chalcogenide glass sample was analyzed according to the temperature. After placing the chalcogenide glass disk between MS ZnS substrates (20 × 30 mm), the sealing test was performed at a temperature of 485 °C for 60 min. Notably, it was found that the Ge-Sb-Se-based chalcogenide glass sealed the MS ZnS substrates well. After the MS ZnS substrates were sealed with chalcogenide glass, they showed a transmission of 55 % over 3~12 μm. The tensile strength of the sealed MS ZnS substrates with Ge-Sb-Se-based chalcogenide glass was analyzed by applying a maximum load of about 240 N, confirming its suitability as a sealing material in the far infrared range.

For national security, approximately 500 facilities have been designated as national security facilities. It is divided into grades A, B, and C depending on the fields such as electrics, energy and public service. In 2016, KINAC developed and suggested the installation standards and evaluation indicators for security equipment for national security facilities and they have been utilized to evaluate and manage the facilities. In order to update them by reflecting the recent security trend of the facilities and new technology, KINAC have investigated and updated the installation standards and evaluation indicators for security equipment. As a part of developing installation standards and evaluation indicators for national security facilities project, we conducted survey to identify the status and capabilities of facilities: how the security system is well designed, which type of security equipment is utilized. According to the results, the passive infrared (PIR) sensor is commonly used for interior intrusion detection (not included in 2016 project). Therefore, we investigated the passive infrared sensor and provided its installation standards and evaluation indicators. PIR sensor detects the energy generated by the objects which is different as their temperatures. PIR sensors do not emit any energy like active infrared sensor, and do not measure the energy. Rather, PIRs measure variation in thermal radiation. PIR sensor detects thermal energy by sensing the change between a heat source and the background temperature. In this paper, the characteristics and features of PIR sensor were discussed. Considering them, the standards and indicators to install/evaluated the PIR sensors were also proposed. The results would support national security facility to design and evaluate their security system.

This experiment was conducted to establish the technology for artificial hay preparation in Korea. Using far-infrared heater, a device that can control temperature, airflow, and far-infrared radiation was produced and conducted on the fourth harvested alfalfa. The drying conditions were carried out by selecting a total of four conditions. For each condition, the radiation rate was set to around 40% (33-42%), and the temperature was set at 58~65℃, and the speed of the airflow was fixed at 60m/s. The overall drying time was set to 30 min in the single and 60 min (30-30 min) and 90 min (30-30-30 min) in the complex condition, and the radiation rate and temperature were changed by time period. In the case of drying condition 1, the final dry matter (DM) content was 46.26%, which did not reach a DM suitable for hay. However, all of the alfalfa corresponding to the remaining drying conditions 2 to 7 showed a DM content of 80% or more, resulting in optimal alfalfa hay production. In power consumption according to the drying conditions, the second drying condition showed the lowest at 4.7 KW, and the remaining drying conditions were as high as 6.5 to 7.1 KW. The crude protein content was found to be high at an average of 25.91% and it showed the highest content in the 5th drying condition (26.93%) and the lowest value in the 6th drying condition (25.16%). The digestibility showed a high value with an average of 84.90%, and there was no significant difference among treatments (p>0.05). Considering the above results, it was judged that drying condition 2 was the most advantageous.

FTIR (Fourier Transform Infrared) and Raman spectra of KJ-II bentonite provided by Clariant Korea were compared with those of MX-80 bentonite. The FTIR spectra were obtained using a Nicolet 5 FTIR spectrometer (Fisher Scientific) equipped with a diamond ATR (Attenuated Total Reflection) module. The spectra were collected for 64 scans with a resolution of 4 cm−1. Raman spectra were obtained using an optical microscope (Olympus, BX43) and a spectrometer (Andor, SR- 500). The laser beam was focused using an objective lens with a magnifying power of 50. The backscattered light from the sample was collected into an optical fiber with a core diameter of 0.4 mm. The Raman signals were recorded with CCDs (Andor, DV401A-BV for 532 nm laser wavelength and DV420A-OE for 638 and 785 nm laser wavelengths). Each pixel of CCD received the signal for 1 s and its 1000 times accumulated data were collected. The FTIR spectra of the two bentonite samples are very similar. The FTIR spectra of both bentonites showed absorption bands at 3623, 3399, 3231 cm−1 in the higher wavenumber region and at 1637, 1443, 1117, 997, 914, 887, 847, 797, 611, 515, 414 cm−1 in the lower wavenumber region. A sharp band at 3623 cm−1 and the strong band at 997 cm−1 correspond to the OH stretching of structural hydroxyl groups and the Si-O stretching vibration, respectively. In addition to these clear bands, several absorption bands observed in this experiment are well matched with the results reported in various literatures. Unlike the FTIR spectrum, it is not easy to observe the Raman bands of bentonite. The reason is that strong fluorescence interferes with the Raman spectrum. The two bentonite samples showed different fluorescence intensities. In the case of MX-80 bentonite, no clear Raman band was observed due to the influence of very strong fluorescence. KJ-II bentonite showed a relatively weak fluorescence intensity and Raman bands were partially visible at around 147, 260, 397, 709, and 1279 cm−1. In particular, the band at 1279 cm−1 is wide and sturdy. It was observed that the non-powder samples showed a better quality spectra. The Raman characteristics of KJ-II bentonite, which depend on the incident laser wavelength and the sample pretreatment, are discussed in detail.

이 연구는 ‘태양 복사’가 ‘가시광선 복사’로, ‘지구 복사’가 ‘적외선 복사’로 상호 대체될 수 있는 개념인가에 대한 문제 인식에서 출발하였다. 이를 위해 각 개념을 어떻게 인식하고 있는지를 드러낼 수 있는 질문지를 통하여 지 구과학 I을 이수한 고등학생들의 인식을 조사하고, 이들의 인식에 영향을 미칠 수 있는 교과서의 서술 및 삽화를 분석 하였다. 이 연구의 주요 결과는 다음과 같다. 첫째, 조사에 참여한 학생들은 모두 태양 복사를 가시광선 영역에서만 방출되는 복사로 인식하고 있으며, 지구 열수지에서 대류·전도·숨은열을 복사에 의한 에너지 전달로 인식하고 있는 학생 들도 약 35%로 나타났다. 둘째, 2015 개정 교육과정의 지구과학 I 6종 교과서를 분석한 결과, 2종에서는 ‘단파 복사’와 ‘장파 복사’라는 용어를 도입하지만 이들에 대한 설명이 없었으며, 다른 2종에서는 태양 복사를 각각 ‘주로 가시광선 형 태의 복사’ 또는 ‘파장이 짧은 가시광선 복사’로 서술하였다. 그 밖의 2종 교과서에 있는 태양 복사와 지구 복사에 관 하여, 파장 영역에 대한 설명이 없거나 ‘단파장/장파장’이라는 모호한 용어가 사용되었다. 아울러 2종의 교과서에서 열 수지 삽화에 일부 오류가 발견되었다. 따라서 교과서들이 단파 복사와 장파 복사에 관한 정확한 용어 정의 없이 태양 복사와 지구 복사를 설명함에 따라 학습자들은 태양 복사와 지구 복사를 각각 가시광선 복사와 적외선 복사라는 개념 으로 인식할 개연성이 있다. 이를 종합해 보면, 교과서에 기술된 불분명한 진술이나 오류가 학생들의 오개념을 유발하 거나 재생산할 수 있음을 함의한다. 이 연구에서 논의된 바가 지구의 열수지와 복사 평형에 대한 교수·학습 과정의 유 용한 참고 자료로 활용되고, 추후 교과서 집필에서도 합리적인 서술 방안을 제안하는 데 기여할 수 있으리라 기대한다.

This study was carried out to investigate the proper wattage and installation distance for the efficient use of nano-carbon fiber infrared heating lamp (NCFIHL), a heating device advantageous for heating energy saving, when the production of watermelon plug seedlings in the plug seedling nursery in winter season. Six small beds were divided into plastic film, and 700 W and 900 W nano-carbon fiber infrared heating lamps were installed at 100 cm above the bed. 1 lamp at central (control), 60 cm interval (2 lamps), and 40 cm interval (3 lamps) heating lamps were installed in each bed inside the greenhouse. All treatments, except the control, were set to keep the night air temperature at 20℃ after lighting the NCFIHL. The leaf temperature showed a tendency to increase fast as the install distance was narrow. The leaf length and leaf width tended to increase as the installation distance of the 700 W heating lamp was narrow. The compactness was high in 700 W heating lamp with 40 cm of installation distance. Therefore, in consideration of maintaining the set temperature at night, installing 700 W electric lamps at 40 cm was an efficient power and installation distance for watermelon grafted seedlings considering economic feasibility.

Variability is one of the major characteristics of Active Galactic Nuclei (AGN), and it is used for understanding the energy generation mechanism in the center of AGN and/or related physical phenomena. It it known that there exists a time lag between AGN light curves simultaneously observed at different wavelengths, which can be used as a tool to estimate the size of the area that produce the radiation. In this paper, We present long term near-infrared variability of optically bright type 1 AGN using the Wide-field Infrared Survey Explorer data. From the Milliquas catalogue v6.4, 73 type 1 QSOs/AGN and 140 quasar candidates are selected that are brighter than 18 mag in optical and located within 5 degree around the ecliptic poles. Light curves in the W1 band (3.4 ㎛) and W2 band (4.6 ㎛) during the period of 2010-2019 were constructed for these objects by extracting multi-epoch photometry data from WISE and NEOWISE all sky survey database. Variability was analyzed based on the excess variance and the probability Pvar . Applying both criteria, the numbers of variable objects are 19 (i.e., 26%) for confirmed AGN and 12 (i.e., 9%) for AGN candidates. The characteristic time scale of the variability (τ) and the variability amplitude (σ) were derived by fitting the DRW model to W1 and W2 light curves. No significant correlation is found between the W1/W2 magnitude and the derived variability parameters. Based on the subsample that are identified in the X-ray source catalog, there exists little correlation between the X-ray luminosity and the variability parameters. We also found four AGN with changing W1-W2 color.

In this paper, we propose dead pixel detection and compensation method using nonlinear estimator for infrared camera. Infrared camera has dead pixel that is abnormal output values due to complex factors such as manufacturing process, electronic parts and so on. Dead pixels are able to affect detecting a small target. So, It needs detection and Compensation process. However, after Compensation, some dead pixels are remained and detected by the human. They are soft dead pixel. The key idea of this proposed method, detecting soft dead pixels, is that design a nonlinear estimator using image data characteristics. This propose is able to not only detect soft dead pixels but also pixel Compensation that reflects infrared camera output characteristics well.

A progressive muscle atrophy is strongly associated with aging, resulting in lower quality of life in elderly individuals. This study was conducted to determine relative hemoglobin (Hb) concentrations in the rabbit model of the sciatic nerve transection injury using non-invasive diffuse optical spectroscopy (DOS). From the 2nd week to the end of the experiment after sciatic nerve injury, a total muscle mass in nerve injured-group (NI group) significantly reduced compared with that in the normal group (p<0.001). During the capillary occlusion after nerve injury, the deoxy-hemoglobin (Hb-R) concentration in NI group significantly increased compared to that in the normal group at the 2nd and 3rd week after sciatic nerve injury (p<0.05). During the capillary release after nerve injury, the oxy-hemoglobin (Hb-O2) concentration in NI group significantly decreased at the 1st and 3rd week, and Hb-R significantly increased at 2nd week, compared to those in the normal group (p<0.05). Histological changes in the gastrocnemius muscle of NI group observed that clear fat filled spaces at the periphery of muscle fibers and angular fibers. From the results of this study, non-invasive DOS could be used to measure changes of Hb concentrations in muscles.