Near infrared reflectance spectroscopy (NIRS) is widely used to assess the nutrient composition of forages. In forage, the leaf to stem ratio of alfalfa greatly affects its forage quality, with a high ratio of leaf indicated as high quality. This study aimed to evaluate the predictability of the alfalfa leaf-to-stem ratio and feed value using NIRS. Alfalfa hay was manually separated into leaves and stems by hand and the analysis samples were then made in the controlled range between 0 and 100%. Calibration models (n=320) were developed using modified partial least squares regression (MPLS) based on cross-validation. The optimal calibrations were selected based on the highest coefficients of determination in cross-validation (R2) and the lowest standard error of cross-validation (SECV). The prediction accuracy for the leaf-to-stem ratio (SECV, 5.95 vs. 5.71%; R2, 0.91 vs. 0.91) in alfalfa hay was comparable. For leaves, the standard error of calibration (SEC) was 4.94% (R2=0.94), and for stems, it was 4.81% (R2=0.94). The leaves and stems of the SEC were 4.94% (R2=0.94) and 4.81% (R2=0.94), respectively. The prediction accuracy for feed value, based on the leaf-to-stem ratio, predicted SECV values of 0.92% (R2=0.88) for crude protein (CP) content, 1.92% (R2=0.91) for neutral detergent fiber (NDF) content, 1.36% (R2=0.91) for total digestibility nutrient (TDN) content, and 9.86 (R2=0.81) for relative feed value (RFV). The results of this study demonstrate the potential of the NIRS method as a reliable tool for predicting the leaf-to-stem ratio of alfalfa hay, and show available techniques for routine feed value evaluation.

목적 : 본 연구의 목적은 근적외선 차단 안경렌즈의 광학적 특성을 분석하고, 근적외선 차단 안경렌즈를 이해하는 데 도움이 되는 자료를 제시하는 것이다. 방법 : 근적외선 차단 안경렌즈(소재 방법 및 코팅 방법)와 일반 렌즈를 시감투과율 0, 2, 3등급( 10종)으로 구 분하여, 250∼1,400 nm의 분광 투과율을 측정하였고, 청색광 및 근적외선 차단율을 산출하였다. 또한, 주행 중 교통 신호등 감지에 대한 적합도를 확인하기 위해 상대 시각 감쇄 계수(Q)를 분석하였다. 결과 : 시감투과율 분류 0, 2, 3등급에서 투과율은 일반렌즈가 근적외선 차단 안경렌즈보다 높았다(p<0.05). 410∼470 nm 영역에서 근적외선 차단 안경렌즈와 일반렌즈의 청색광 차단율은 차이가 없었고(p>0.05), 470 nm ∼500 nm 영역의 0, 2, 3등급은 차이가 있었다(p<0.05). 근적외선(780 nm∼1,400 nm) 영역의 차단율은 0, 2, 3등급에서 근적외선 차단 안경렌즈가 일반 렌즈에 비해 높았고(p<0.05), 근적외선 차단 성능이 더 우수함을 입증 하였다. 근적외선의 침투로 인해 영향을 받는 눈과 피부 영역에서 근적외선 차단 안경렌즈는 일반 렌즈보다 차단율 이 높았고(p<0.05), 일반렌즈 보다 근적외선의 침투를 감소시킬 수 있을 것이다. 동일한 차단율의 0등급 근적외선 차단 안경렌즈는 소재 방식보다 코팅방식 차단 렌즈의 차단 성능이 좋았다(p<0.05). 시감투과율 0, 2, 3등급에서 근적외선 차단 안경렌즈는 주행 중 교통 신호등 감지를 위한 색 구별에 적합했다. 결론 : 시감투과율 분류 0, 2, 3등급에서 근적외선 차단 안경렌즈는 일반 렌즈에 비해 높은 차단율을 나타내어 그 성능을 입증하였고, 근적외선의 영향을 받는 눈과 피부의 파장 영역에서도 근적외선의 침투를 감소시킬 수 있을 것이다. 결과적으로, 근적외선 차단 안경렌즈의 광학적 특성에 대해 이해하는데 도움이 되는 자료를 제공하였다.

경동맥의 치료 초음파 자극이 뇌의 생리적인 작용에 미치는 영향은 여전히 연구가 필요한 상황이다. 이에 본 연구 에서는 치료용 초음파를 이용한 비침습적이고, 정량적인 열자극 기법을 이용하여 경동맥의 자극을 통해 뇌의 생리적 인 기능을 개선하고 건강한 뇌 기능을 유지할 수 있는 방법을 제안하고자 하였다. 건강한 20대 성인 남녀 27명을 대상으로 연구를 진행하였다. 바로 누운 자세에서 진단용 초음파를 이용하여 우측 총경동맥(right common carotid artery, CCA)의 자극 위치를 확인하고, 우측 목빗근(sternocleidomastoid muscle)에 치료 초음파 자극을 적용하였다. 치료 초음파 자극은 치료용 초음파를 이용하여 3MHz의 주파수에서 총 2가지 강도 (5W/cm2 and 10W/cm2)에서 각각 2분 동안 중재하였다. 근적외선분광법(near-infrared spectroscopy, NIRS)을 이용하 여 대뇌산소포화도(regional cerebral oxygen saturation, rSO2) 및 헤모글로빈(hemoglobin, Hb) 농도의 변화를 측정 하여 비교하였으며, 추가적으로 강도에 따른 중재 구간별 변화를 비교 분석하였다. 두피와 대뇌피질 사이(Shallow) 영역에서 rSO2는 강도에 따라서 서로 증감이 다르게 나타났다. 즉, 5W/cm2에서는 중재전과 비교하여 중재중과 중재후에 모두 감소하는 경향을 보였고, 10W/cm2에서는 모두 증가하는 경향을 보였지 만, 모두 통계적으로 유의한 차이를 보이지는 않았다. 반면, 대뇌피질(Deep) 영역에서는 중재중에서 강도와 상관없이 통계적으로 유의한 감소를 보였고(p = .001 for 5W/cm2; p < .001 for 10W/cm2), 중재중과 비교하여 중재후에는 다시 중재전의 상태로 회복되는 경향을 보였다(p = .016 for 5W/cm2; p = .012 for 1 0W/cm2). 옥시헤모글로빈 (oxyhemoglobin, HbO)의 변화는 5W/cm2 자극에서 중재중에서만 유의한 증가를 보였고(p = .036), 디옥시헤모글로 빈(deoxyhemoglobin, HbR)은 감소하는 경향을 나타냈지만, 유의한 차이를 보이지는 않았다. 10W/cm2 자극에서 HbO와 HbR이 모두 감소하는 경향을 보였지만, 유의한 차이를 보이지 않았다. 강도에 따른 변화는 Shallow 영역에 서 rSO2가 유의한 차이를 보였다(중재중, p = .023; 중재후, p = .022). 결론적으로 3MHz의 주파수와 5W/cm2와 10W/cm2 강도로 중재를 수행하게 된다면, 중재중에 Deep 영역의 rSO2 의 감소를 야기한다는 것을 볼 수 있었다. 10W/cm2의 강한 강도의 자극에서는 Shallow 영역에서 rSO2가 증가하고, Deep 영역에서는 감소하는 것을 보여주었다. 이는 강한 강도의 자극에 의해 내경동맥의 혈류 증가로 인한 대뇌피질 에서의 효과적인 자극이 아니라 외경동맥의 혈류 증가로 인하여 Shallow 영역에서의 혈류 공급의 과다로 인한 현상 이 나타난 것으로 보여 진다. 반면, 대뇌에서 HbO는 5W/cm2의 강도에서 증가하였고, 이는 전반적인 산소 공급량이 높아졌음을 의미한다. 이에 적절한 강도의 치료용 초음파 자극을 사용한다면 기존에 알려져 있던 뇌혈류의 개선을 통하여 뇌혈관 건강을 개선하는 기능과 더불어 대뇌의 생리적인 기능을 조절하여 뇌기능의 개선에 기여할 수 있을 것으로 보인다.

This project aimed to understand the near-infrared (NIR), intensity, and reflectivity characteristics of LiDAR for measuring retroreflectivity and to understand the correlation between the characteristics of LiDAR and retroreflectivity. A 600 m-testbed was investigated using a survey vehicle equipped with LiDAR, and the testbed retroreflectivity and LiDAR data measurement values were compared. The reflectivity and intensity at night were not affected by sunlight compared with daytime, enabling stable data collection. However, NIR reacted very sensitively to sunlight, and the difference between daytime and nighttime NIR values was very large. In addition, by comparing the absolute error between the retroreflectivity and LiDAR data, we observed that the reflectivity was consistent with the data difference between day and night, and it was not significantly affected by sunlight. However, the intensity showed that the daytime measurement data were more scattered than the nighttime measurement data, resulting in low-precision collection stability caused by sunlight. An analysis of the correlation between retroreflectivity and LiDAR data using 40 data points revealed that the reflectivity and intensity data at night were highly correlated with retroreflectivity, with a P-value of less than 0.05. Reflectivity and intensity values at night correlate with retroreflectivity. The NIR light is sensitive to sunlight. Thus, it can be used as a solar correction index for future retroreflectivity analyses using intensity.

목적 : 적외선 차단렌즈의 근적외선 차단율과 시감투과율을 제조방식 및 근적외선 차단제 첨가 여부에 따라 조 사하고, 근적외선 차단렌즈의 개발 방향에 대하고 논하였다. 방법 : 시중에서 유통되고 있는 국내외 브랜드의 근적외선 차단렌즈 20종(C-type 10종, M-type 5종, TMtype 5종)을 대상으로 가시광선에서 근적외선에 이르는 380~1,400 nm 영역에서 5 nm 간격으로 투과율을 측정한 후, KS B ISO 13666 표준에 따라 근적외선 차단율과 시감투과율 구하였다. 결과 : 근적외선 차단율은 TM—type이 평균 62.3%로 가장 우수하였지만, 착색렌즈에 미러코팅을 한 관계로 시 감투과율은 평균 20.2%로 매우 낮았다. M—type의 경우는 근적외선 차단제의 첨가로 인한 근적외선 차단효과가 명확하게 나타나기는 했지만, 근적외선 차단제를 첨가하지 않은 C-type의 렌즈의 근적외선 차단율보다 그 성능이 떨어졌고, 시감투과율 또한 낮았다. 근적외선 차단제가 첨가되지 않은 C-type의 렌즈들에서 근적외선 차단율은 우 수하였을 뿐만 아니라, 시감투과율 또한 무반사 렌즈 수준으로 높게 나타났다. 결론 : 최적화된 코팅설계가 적용되면 AR 렌즈 수준의 높은 시감투과율을 보이면서 TM-type의 근적외선 차단 율을 능가하는 우수한 근적외선 차단렌즈를 개발할 수 있다는 점에서 근적외선 차단렌즈의 설계 방향은 C-type이 가장 효과적이라 할 수 있다.

In this study, infrared thermometry techniques were used to conduct surface wetting performance tests (wicking tests) on micropillar structures with good fluid supply capabilities to enhance the critical heat flux. Wicking tests were conducted based on various micropillar shapes (i.e., diameter and spacing) to investigate the surface wetting performance near the boiling point of the fluid(~100°C). The surface temperature was increased from 20°C to 95°C, to examine the wicking performance The shape of the micropillars were quantified by the roughness and the effect of the roughness and temperature on the wicking performance was analyzed. As a result, we confirmed that the roughness of the micropillars increases the capillary pressure, improving the wicking performance. The sample D04 G10 with the highest roughness coefficient at room temperature (r=2.51) exhibited the highest wicking coefficient, showing a 170% improvement in wicking performance compared to D04G20 with the smallest roughness coefficient at room temperature(r=1.51). Additionally, the D04 G10 sample (r=2.51) recorded a 50% improvement in the wicking coefficient at the highest temperature(95°C) compared to room temperature(20°C). The wicking coefficient data will be utilized as a database for developing a new correlation for critical heat flux.

Owing to the rapid rise of global energy demands, the operation of nuclear power plants is still indispensable. However, following the nuclear accident at Fukushima-Daiichi in 2011, the secure sequestration of radioactive waste has become critical for ensuring safe operations. Among various forms of nuclear wastes, capturing radioactive organic iodide (ROIs, e.g., methyl iodide, ethyl iodide, and propyl iodide) as one of the important species in gas phase waste has been challenged owing to the insufficient sorbent materials. The environmental release of ROIs with high volatility can give rise to adverse effects, including the accumulation of these substances in the thyroid and the development of conditions such as hypothyroidism and thyroid cancer. Compared to an iodine molecule, ROIs exhibit low affinity for conventional sorbents such as Ag@mordenite zeolite and triethylenediamine-impregnated activated carbon (TED@AC), resulting in lower sorption rates and capacities. Furthermore, in conditions resembling practical adsorption environments with high humidity, the presence of H2O significantly impedes the adsorption process, leading to a nearly complete cessation of adsorption. To address these issues, metal-organic frameworks (MOFs) can be effective alternative sorbents owing to their high surface area and designable and tailorable pore properties. In addition, the wellfined crystalline structures of MOFs render in-depth study on the structure-properties relationship. However, there has been limited research on the adsorption of ROIs using MOFs, with the majority of adsorption processes relying on highly reversible physisorption. This type of ROIs adsorption not only exists in a precarious state that is susceptible to volatilization but also exhibits significantly reduced adsorption capabilities in humid environments. Thus, for the secure adsorption of the volatile ROIs, the development of sorbents capable of chemisorption is highly desirable. In this study, we focused on ROIs adsorption by electrophilic aromatic substitution with the electron-rich m-DOBDC4− (m-DOBDC4− = 4,6-dioxo-1,3-benzenedicarboxylate) present in Co2(m -DOBDC). The chemisorption of ROIs via electrophilic aromatic substitution not only leads to the formation of C-C bonds, ensuring stability but also triggers color changes in the crystal by interacting with open-metal sites and iodide ions. Leveraging these advantages, we developed an infrared radiation-based sensing method that demonstrates superior performance, exhibiting high adsorption capacities and rates, even under the challenging conditions of high-humidity practical environments.

This study presents a method for analyzing the surface temperatures of specific facilities, such as the 5 MWe reactor within the Yongbyon Nuclear Complex, to explore its potential utility in monitoring suspected nuclear-related activities in North Korea using thermal infrared (TIR) satellite imagery (Landsat series). TIR band data is utilized to derive surface temperatures in the specified areas, and the temperatures are analyzed on a monthly basis to examine any patterns within these regions. This research provides a pattern-of-life on temperature variation for the target areas through multiple TIR image datasets, offering additional information to analyze facilities’ operational status in remote and inaccessible regions.

Fulvic acid, a humic substance with unique properties, has sparked interest due to its potential applications in the treatment of allergic diseases, Alzheimer's disease, and as a microplastic adsorbent. However, conventional extraction methods produce insufficient quantities for commercial use, which has prompted research to enhance fulvic acid production. In this study, we investigated the impact of Saccharomyces cerevisiae fermentation on the yield and spectral characteristics of fulvic acid extracted from white peat. Fulvic acid was extracted from both S. cerevisiae-treated and untreated white peats using acid precipitation. The yield of fulvic acid from the S. cerevisiae treated group reached its highest at 3.5 % after 72 hr of fermentation, which was significantly higher than the untreated group (1.1 %). Fourier Transform Infrared (FTIR) analysis revealed similarities in functional groups and characteristic absorption bands between the treated and untreated fulvic acid samples. These findings suggest that S. cerevisiae fermentation can increase the yield of fulvic acid extracted from white peat, providing a promising approach for enhancing the commercial viability of fulvic acid production.

Infrared radiation (IR) refers to the region of the electromagnetic radiation spectrum where wavelengths range from about 700 nm to 1 mm. Any object with a temperature above absolute zero (0 K) radiates in the infrared region, and a material that transmits radiant energy in the range of 0.74 to 1.4 um is referred to as a near-infrared optical material. Germanatebased glass is attracting attention as a glass material for infrared optical lenses because of its simple manufacturing process. With the recent development of the glass molding press (GMP) process, thermal imaging cameras using oxide-based infrared lenses can be easily mass-produced, expanding their uses. To improve the mechanical and optical properties of commercial materials consisting of ternary systems, germanate-based heavy metal oxide glasses were prepared using a melt-cooling method. The fabricated samples were evaluated for thermal, structural, and optical properties using DSC, XRD, and XRF, respectively. To derive a composition with high glass stability for lens applications, ZnO and Sb2O3 were substituted at 0, 1, 2, 3, and 4 mol%. The glass with 1 mol% added Sb2O3 was confirmed to have the optimal conditions, with an optical transmittance of 80 % or more, a glass transition temperature of 660 °C, a refractive index of 1.810, and a Vickers hardness of 558. The possibility of its application as an alternative infrared lens material to existing commercial materials capable of GMP processing was confirmed.