• 산업경영시스템학회지
• /
• 제46권3호
• /
• pp.59-68
• /
• 2023

Currently, yellow phosphor of Y3Al5O12:Ce3+ (YAG:Ce) fluorescent material is applied to a 450~480nm blue LED light source to implement a white LED device and it has a simple structure, can obtain sufficient luminance, and is economical. However, in this method, in terms of spectrum analysis, it is difficult to mass-produce white LEDs having the same color coordinates due to color separation cause by the wide wavelength gap between blue and yellow band. There is a disadvantage that it is difficult to control optical properties such as color stability and color rendering. In addition, this method does not emit purple light in the range of 380 to 420nm, so it is white without purple color that can not implement the spectrum of the entire visible light spectrum as like sunlight. Because of this, it is difficult to implement a color rendering index(CRI) of 90 or higher, and natural light characteristics such as sunlight can not be expected. For this, need for a method of implementing sunlight with one LED by using a method of combining phosphors with one light source, rather than a method of combining red, blue, and yellow LEDs. Using this method, the characteristics of an artificial sunlight LED device with a spectrum similar to that of sunlight were demonstrated by implementing LED devices of various color temperatures with high color rendering by injecting phosphors into a 405nm deep blue LED light source. In order to find the spectrum closest to sunlight, different combinations of phosphors were repeatedly fabricated and tested. In addition, reliability and mass productivity were verified through temperature and humidity tests and ink penetration tests.

• 한국신뢰성학회지:신뢰성응용연구
• /
• 제11권4호
• /
• pp.343-356
• /
• 2011

This paper proposes an accelerated life evaluation of drive shaft. The life test of drive shaft for independent suspension type AWD vehicle should be performed by use of the least test sample because many number of samples can't be used for the test because of its mass capacity and high price. We calculated the no failure test time by application of no failure test concept, and the already performed test data for drive shaft are applied for some kinds of reliability coefficients which are needed for calculation of life test time. And, for analysis of real driving condition of vehicle, the load spectrum is prepared using the needed road condition and vehicle data. The inverse power model is used for accelerated life test. The equivalent torque of load spectrum is achieved by use of Miner's Rule, and then the final accelerating condition is determined by decision of the accelerated test torque. This paper shows that the accelerated life test results corresponds with the target life and the proposed life test method can be very well applied to no failure life test for mass capacity machinery components.

• 한국군사과학기술학회지
• /
• 제14권2호
• /
• pp.289-298
• /
• 2011

TMAH-based Py-MS has been investigated to apply for a real-time classification of biological agents in the field. Acquiring reproducible data from mass spectrometry is a key to biological detection in the field. Nevertheless, it has been little studied on what factors could affect to the reproducibility of the TMAH-based Py-MS spectrum patterns. Given the TMAH-based Py-MS applied to the field system, several factors which could affect to the reproducible pattern of TMAH-based Py-MS spectra are needed to be examined, including changes in TMAH injection volume, growth temperature for microorganism, and number of cells collected in pyrolyzer, and implication of stabilizer used for lyophilization. This study showed that the reproducibility of the spectrum patterns was significantly hindered by changes in TMAH concentration and cell number, and stabilizer implication but not by growth temperature. Among those at low TMAH concentration(0.015m) was not observed the significant alterations of the spectrum pattern even when its injection volume was changed, yet was in different cell numbers and stabilizer implication.

• 한국염색가공학회지
• /
• 제10권3호
• /
• pp.20-28
• /
• 1998

Natural indigo colorants were prepared by extraction of polygonum tintorium which was harvested just in the blooming season(in the late of July). The components were analyzed by TLC and HPLC, and its structures were analyzed by FT-IR, EI-mass and NMR. The dyeing mechanism and fermentation conditions were investigated. Its colour fastness was studied as well. The results obtained are summarized as follows ; The natural indigo powder was dissolved in DMSO and developed in eluent, $CHCl_3/CH_3CN(8.5:1.5v/v)$ by means of TLC for its quality analysis. It was segregated into indirubin as il red colour and indigo as a blue colour. In case of HPLC analysis, the retention times of indirubin and indigo were 7.442 and 6.543, respectively. FT-IR spectrum of indirubin showed a peak for NH residue between 3200 and $3300cm^{-1}.^1H-NMR$ spectrum for indigo displayed AA'BB' spin system caused by indole structure between 6.5 and 7.7ppm of H4, 5, 6 and 7, and -NH proton for indirubin showed an singlet between 10.88 and. 11.0ppm. EI-mass spectrum of indigo an d indirubin both disclosed their molecular size as 262 and it implies that these two substances are isomer.

• 정신신체의학
• /
• 제23권2호
• /
• pp.129-135
• /
• 2015

연구목적 지난 20년 동안 아동에 있어 과체중(overweight)의 유병률이 증가하였다. 또한 자폐스펙트럼장애(Autism spectrum disorder, ASD)를 진단 받는 아동의 숫자도 매해 증가하고 있다. ASD를 진단받은 아동의 비만(obesity)에 대한 연구가 미국에서는 활발하게 이루어지고 있으나, 한국에서는 많은 연구가 수행되지는 않았다. 따라서 이 연구의 목적은 ASD를 지닌 아동의 과체중 및 비만의 유병률 및 실태를 알아보고자 한다. 방 법 2012년부터 2015년까지의 3세에서 18세 사이의 소아 청소년을 대상으로 대전 건양대학교병원 정신건강의학과 외래에 내원한 소아 청소년 환자의 의무기록을 조사하였다. 각각의 의무기록으로부터 진단적, 의학적, 인구학적 정보를 추출하였다. 신체질량지수인 Body mass index(BMI)는 병원에서 시행하여 의무기록에 기입되어 있는 키와 체중으로 토대로 계산 하였다. 나이와 성별을 보정한 BMI z-score을 사용하였다. 결 과 ASD를 지닌 아동 군에서 ASD를 지니지 않은 군보다 더 높은 BMI 값을 가지고 있으며, 이는 통계적으로 유의하였다(p=0.032). 또한 ASD를 지닌 아동들이 ASD를 지니지 않은 아동에 비해 비교적 더욱 과체중 및 비만인 것으로 나타났다. 유병률에 있어서는 ASD가 있는 아동(35%)이 ASD가 없는 아동(19%)에 비해 과체중 및 비만인 것으로 간주되었다. 결 론 ASD를 지닌 아동과 지니지 않은 대상에 대한 과체중 및 비만에 관한 연구로서, ASD를 지닌 아동이 그렇지 않은 군에 비해 더욱 과체중 및 비만을 지니고 있음을 보여주었다. 향후 ASD 비만에 대한 유발 및 보호인자에 대한 장기적이고 심화된 연구가 필요하겠다.

• 약학회지
• /
• 제42권6호
• /
• pp.552-557
• /
• 1998

Acyl CoA synthetase inhibitor, was purified from the culture broth of a Bacillus sp. B-6, which had been isolated from soil, by chloroform extract, silica gel column chro matography and preparative TLC. The purified acyl CoA synthetase inhibitor showed higher Antifungal activity against C. al-bicans (MIC: 8${\mu}$g/ml). Though the analysis of UV spectrum, melting point, IR spectrum, Mass-spectrum, $^1H$-NMR and $^{13}C$-NMR spectrum, the inhibitor could be identified as phenazine-l-carboxylic acid.

• 천문학회보
• /
• 제42권1호
• /
• pp.43.1-43.1
• /
• 2017

We investigate properties of black hole (BH) binaries formed in globular clusters, by using direct N-body simulations. Comparing with previous studies which usually considered single BH masses, our models consist of two-component BH masses, or continuous BH mass function with single mass ordinary cluster stars. During the early stage of dynamical evolution, initially distributed BHs are move to the cluster center by dynamical friction, then BH-BH binaries start to be formed, and eventually be ejected from the cluster due to three body interaction. Finally we find the formation efficiency of high mass BHs are alwats larger than that of lower mass BHs, implying that a BH mass spectrum expected from GW observation should be biased to high mass. In addition, mass ratios of BHs in binaries prefer similar masses (ratio~1), while the most extreme case is less than 3. Expected merger rate from our models is about 7 BH-BH mergers per $Mpc^3$ per yr.

• 대한화학회지
• /
• 제51권4호
• /
• pp.356-360
• /
• 2007

sodium ethoxide의 존재하에서 3,5-diaryl-cyclohex-2-en-1-one와 methyl vinyl ketone로부터 5,7-Diaryl- 3,4,6-trihydronaphthalen-2-ones가 합성되었다. 이 생성물은 IR, UV-Visible, 1H-NMR, 13C-NMR 그리고 mass spectral techniques로 구조를 규명하였다. 1H과 13C signals의 피크들은 HSQC spectrum을 찍어 정확히 규명하였다.

• Nuclear Engineering and Technology
• /
• 제49권3호
• /
• pp.645-650
• /
• 2017

This technical note demonstrates the feasibility of using laser ablation inductively coupled plasma mass spectrometry for the characterization of U-7Mo/Ale5Si dispersion fuel. Our measurements show 5.0% Relative Standard Deviation (RSD) for the reproducibility of measured $^{98}Mo/^{238}U$ ratios in fuel particles from spot analysis, and 3.4% RSD for $^{98}Mo/^{238}U$ ratios in a NIST-SRM 612 glass standard. Line scanning allows for the distinction of U-7Mo fuel particles from the Al-5Si matrix. Each mass spectrum peak indicates the presence of U-7Mo fuel particles, and the time width of each peak corresponds to the size of that fuel particle. The size of the fuel particles is estimated from the time width of the mass spectrum peak for $^{98}Mo$ by considering the scan rate used during the line scan. This preliminary application clearly demonstrates that laser ablation inductively coupled plasma mass spectrometry can directly identify isotope ratios and sizes of the fuel particles in U-Mo/Al dispersion fuel. Once optimized further, this instrument will be a powerful tool for investigating irradiated dispersion fuels in terms of fission product distributions in fuel matrices, and the changes in fuel particle size or shape after irradiation.

• Journal of Microbiology and Biotechnology
• /
• 제9권5호
• /
• pp.650-654
• /
• 1999

Undaria pinnatifida oxidized by nitric acid had a high capacity of Cu/sup 2+/ uptake (3.5 mmol Cu/sup 2+/g dry mass) at pH 4 and showed high affinity to Cu/sup 2+/ and Pb/sup 2+/, in a mixed-metal system, compared to Ca/sup 2+/ and Mg/sup 2+/. The IR spectrum showed increase of carboxylic acid on the surface of Undaria pinnatifida, mostly due to the effect of the oxidation reaction.