• Asian-Australasian Journal of Animal Sciences
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• 제14권2호
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• pp.263-267
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• 2001

Beef samples of loin eye area from New Zealand, USA and three quality grades of Hanwoo were analyzed using near infrared spectrophotometer with reference values from laboratory optical Chromameter to determine effective spectrum range and mathematical treatment for determination of color values. $R^2s$ of prediction models were not improved much by calibrating with whole light range (400~2500 nm) compared to using visible range (400~1100 nm). Standard errors of calibration and prediction were influenced by possible bias due to sampling non-homogeneous sample sources. However, partial differentiation in the first order was more stable against sampling biases than second derivatives of the spectra. Lightness value was little different among the five sample sources of beef. Beef samples from USA were brighter and more reddish than beefs of Hanwoo or from New Zealand (p<0.05). Yellowness of USA beef was the highest followed by beef from New Zealand, which was also higher than Hanwoo beefs of three quality grades (p<0.05).

• 한국식품영양과학회지
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• 제26권3호
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• pp.514-520
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• 1997

The purpose of this study is to provide the reference data for estimating body composition and developing equations for prediction of percent body fat. This study was designed of two aspects: Comparison of percent body fat measurements between two operators. comparison of percent body fat measurements among four instruments. Percent body fat of college girls(n=71) aged 18-24 was measured by skinfold thickness, near-infratred interactance(Futrex-5000), and bioelectrical impedance analysis (TBF-105, Spectrum II). All measurements were duplicated & measured by two operators. The results are summarized as follows: Percent body fat observed from two operators had no significant difference. There was significant difference from four instruments. However, we found close relation between Skinfold thickness & TBF-105, Spectrum II & Near-infrared interactance. Four instruments have several assumptions and limitations. Therefore, many researches for developing new equations are required for Korean people.

• Journal of Advanced Marine Engineering and Technology
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• 제20권3호
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• pp.11-18
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• 1996

Liquid droplets of water and argon surrounded by their vapor have been simulated by the milecular dynamics method. To explore the surface phenomena of clusters, each molecule is classified into 'liquid', 'surface', or 'vapor' with respect to the number of neighbor molecules. The contribution of a 'surface' molecule of the water cluster to the far infrared spectrum is almist the same as that of the 'liquid' molecule. Hence, the liquid-vapor interface is viewed as geometrically and temporally varying boundary of 'liquid' molecules with only a single layer of 'surface' molecules that might have different characteristics from the 'liquid' molecules. The time scale of the 'phase change' of each molecule is estimated for the argon cluster by observing the instantancous kinetic and potential energies of each molecule. To compare the feature of clusters with macroscopic droplets, the temperature dependence of the surface tension of the argon cluster is estimated.

• 대한화학회지
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• 제18권4호
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• pp.289-296
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• 1974

Bombina Orientalis(무당개구리)의 복피로부터 암적색의 색소를 추출하여 TLC 및 column chromatography 로 10여종의 carotenoid를 분리하여 visible 및 IR-spectrum을 조사하였다. 물리, 화학적 성질, chromatomatographic 성질 visible 및 IR-spectral 특성을 이용하여 주색소는 ${\beta}$-carotene과 4-hydroxy-echinenone임을 확인하였다.

• 비파괴검사학회지
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• 제30권2호
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• pp.121-125
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• 2010

회전기기의 결함진단에 있어서 기존의 방법과 달리 적외선열화상기술은 회전기기의 결함진단에 대해 비접촉, 비파괴 및 상태감시 모니터링을 할 수 있다. 본 논문에서는 적외선열화상 상태진단을 기반으로 하는 회전기기의 결함진단에 대한 새로운 접근법을 제안한다. 따라서 회전기에서 가장 많이 사용되어지는 볼베어링을 이용하여 실험을 수행하였고, 진동 스펙트럼 분석과 적외선열화상을 이용하여 실시간 모니터링을 수행하였다. 적외선열화상기법을 이용하여 볼베어링의 윤활 불균형에 따른 온도 특성을 확인할 수 있었다. 이러한 실험을 통한 결과를 분석 검토하여 향후 산업전반의 회전기기의 상태감시연구에 있어서 다양한 분야에 사용되어 질 것으로 예상된다.

• 한국통신학회논문지
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• 제25권1B호
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• pp.175-182
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• 2000

적외선을 이용한 수/발광 다이오드에 집적소자를 혼합한 Hybrid형 단거리 광무선 통신용 원칩모듈을 개발하였다. 발광다이오드는 850nm 의 적외선파장을 30$^{\circ}$지향각을 갖는 AlGaAs계 고속신호용으로서 전파지연이 60 ns 이며, PIN 포토다이오드는 Si계 반도체 수광소자로써 450-1050nm의 파장대에서 수광 흡수율이 양호하고 필터겸용 블록 에포시렌즈를 750nm 파장 저역대를 여과시켰다. 데이터 전송속도는 115.2 kbps이며 IrDA1.0 SIR 표준조건에서 동작이 양호함을 확인하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1998년도 추계학술대회 논문집
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• pp.57-60
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• 1998

Poly(3-hexylthiophene)(P3HT) was synthesized by use of FeCl$_3$ as a oxidizing agent at $25^{\circ}C$. The infrared spectrum of our polymer gave good evidence for the conjugation of 3-hexylthiophene monomer unit. P3HT contains the HT(head-to-tail) linkage larger than 64% based on NMR analysis. Electronic absorption and photoluminescence studies show that cast films of P3HT have three exciting state. Absorption spectrum was separated with three maximum peaks by Giese-French method and shifted to the shorter wavelength with increasing temperature. Separated absorption spectrum of P3HT is well adapted to PL peak appeared at longer wavelength. Low temperature PL spectrum is well separated at 669nm, 733nm and 812nm.

• 비파괴검사학회지
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• 제30권6호
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• pp.558-563
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• 2010

In this paper, the novel approach for the fault diagnosis of the bearing equipped with rotational mechanical facilities was studied. As research works, by applying the ball bearing used extensively in many industrial fields, experiments were conducted in order to propose the new prognostic method about the condition monitoring for the rotational bodies based on the condition analysis of infrared thermography. Also, by using the vibration spectrum analysis, the real time monitoring was performed. As results, it was confirmed that infrared thermography method could be adapted into monitor and diagnose the fault for bearing by evaluating quantitatively and qualitatively the temperature characteristics according to the condition of the ball bearing.

• 한국재료학회지
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• 제6권6호
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• pp.555-560
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• 1996

The vibrational behavior and the molecular dynamics of the high Tc superconductor Ba0.6K0.4BiO3 have been studied experimentally and by atomistic computer simulation methods. For Ba0.6K0.4BiO3, the vibrational spectrum is dominated by oxygen ion modes from 150cm-1 to 820cm-1 including infrared absorption bands at 330, 480, 640 and 830cm-1including infrared absorption bands at 330, 480, 640 and 830cm-1at room temperature. Band assignments are discussed in relation to those bands predicted by simulations, and the infrared and Raman measurements reported in the literature.

• 식품과학과 산업
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• 제55권1호
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• pp.2-22
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• 2022

Near-infrared spectroscopy (NIRS) is one of the representative non-destructive and eco-friendly analysis methods used for rapid analysis of various ingredients in the food industry. To develop analysis model with NIRS, Chemometrics are applied after pre-treatment of spectrum. Many studies have been reviewed on the analysis of general and functional components for agricultural and livestock products. In the case of livestock products, some studies have been conducted for on-line analysis. This study investigated results on various samples and component applying near-infrared spectroscopy. Furthermore, the results according to sample condition were compared. It was confirmed that NIRS is applied to various fields in the food industry.