• 한국통신학회논문지
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• 제28권9B호
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• pp.823-833
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• 2003

인터넷에서 실시간 서비스를 지원하기 위해서는 큐 관리 및 스케줄링 기법이 고도화되어야 한다. 기존의 큐 관리 기법은 TCP 플로우의 혼잡을 제어하는 기능은 제공하고 있으나 실시간 서비스 지원에는 문제점을 가지고 있다. 즉, 큐가 어느 정도 점유된 이후 계속적인 버스트 성의 트래픽이 발생할 경우 성능이 급격히 떨어지고, 특히 큰 지터 값으로 인해 실시간 전송에 부적절하다. 본 논문에서는 최대 임계값과 큐 가중치 등의 RED 파라미터를 큐 상태에 따라 적응적으로 조정하여 실시간 서비스에 대한 지연 및 지터 성능을 향상시킬 수 있는 상태 의존 RED (SDRED; State Dependent Random Early Detection) 큐 관리 및 동적 스케줄링 기법을 제안한다. 제안한 기법은 큐 상태에 따라 RED의 최대 임계값과 큐 가중치를 네 개의 서로 다른 레벨로 변경하여 트래픽 상황에 적응하도록 설계하였으며, 시뮬레이션을 통하여 SDRED가 평균 큐 크기를 가지는 RED나 평균 큐 크기를 가지지 않고 현재의 큐 크기를 사용하여 흔잡을 제어하는 BLUE, 그리고 RED 게이트웨이의 수율이나 지연 특성을 향상하기 위해 제안된 ARED 및 DSRED에 비해 낮은 지연 값과 안정적인 지터 값을 나타냄을 검증하였다.

• Journal of Nutrition and Health
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• 제33권3호
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• pp.257-262
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• 2000

This paper is to report our findings that vitamin B6 and folate nutritional state in the rural elderly population with alcohol dependency is poor. The present study was carried out to assess vitamin B6 and folate status in the 17 rural elderly subjects with alcohol dependency and 15 age-and sex-matched controls. Plasma and red cell folate concentrations were analyzed microbiologically, and pyridoxal-5-phosphate dependent erythrocyte alanine aspartate transminase(EAST) activity coefficients were determined using enzyme-coenzyme saturation kinetics. There was no difference in the amount of vitamin consumed between the two groups, and their intakes were 64% and 74.7%, respectively of the Korean dietary recommended allowances for vitamin B6 and folate. The mean percent activation for EAST of the total subjects was greater than 80%, suggesting an inadequate vitamin B6 status between the two groups. Folate concentrations in the red cell, but not in the plasma were significantly lower in the alcohol dependent(141.9ng/ml) subjects than that of the control(233.2ng/ml). Cigarette smokers had lower vitamin B6 and folate levels. Plasma and red cell folate levels were highest among the non-smoking, non-alcohol dependent subjects(11.7 and 257.3ng/ml, respectively) and lowest in the smoker-alcohol dependent group(6.7 and 132.9ng/ml). Finding ways to improve vitamin nutritional state such as vitamin supplementation might be necessary for the rural elderly people, especially for those with alcohol dependency.

• 한국응용과학기술학회지
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• 제20권4호
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• pp.366-371
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• 2003

In this paper, it was studied about the red-sensitive layer. UV-Vis data of the dye at monomeric and J-state were considered with respect to their performance(contrast, speed, density and fog) in photographic emulsion. The sensitizing effect of the dye is found to be strongly structure-dependent. Naphthctbiazolo carbocyanine dye can be used as red sensitizing dye for the spectral sensitization of photographic emulsion.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.847-850
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• 2008

Three thermally stable red dyes of azo, quinacridone and perylene derivatives were synthesized and dye-based color filters were manufactured for liquid crystal display. Aggregation behavior of the dyes and their spectral property in film state were investigated by concentration dependent spectroscopy and field emission scanning electron microscopy (FE-SEM). These dyes have remarkable difference on their aggregation behavior in film state. Such difference of aggregation behavior affects the spectral property of the film, and it can cause decreasing the transmittance of dye-based color filters.

• Bulletin of the Korean Chemical Society
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• 제13권6호
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• pp.613-620
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• 1992

The solvent-dependent photophysical properties of 2-biphenylcarboxylic acid (2BPCA) and 4-biphenylcarboxylic acid(4BPCA), which have a pre-twisted conformation in the ground state, have been investigated. The fluorescence spectra of 4BPCA show vibrational structure with a non-mirror image to the absorption spectra in nonpolar solvent while those of 2BPCA show no structure even in nonpolar solvents. As the solvent polarity increases, the fluorescence spectra become diffuse and broad with a strong red shift resulting in the large Stokes shift. The large fluorescence Stokes shift of BPCA's in polar solvent is also partially due to an intramolecular charge transfer (ICT) interaction in the excited state, as demonstrated by the large dipole moment in the excited state (7.6-10.6 D). The fluorescence decay behaviors of BPCA's (decay-times and their pre-exponential factors) also depend on solvent polarity in agreement with the solvent-dependent properties of the steady-state fluorecence. The data have been discussed in terms of change in the excited-state potential energy surface with respect to change of the dihedral angle of biphenyl moiety.

• Rapid Communication in Photoscience
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• 제3권4호
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• pp.85-87
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• 2014

We studied the characteristics of emissive state of the first (p-G1) and second (p-G2) generation of phenylacetylene dendrimers bearing stilbene as a core by using time-resolved fluorescence spectroscopy in cyclohexane (c-Hex) and N, N-dimethylformide (DMF), which are nonpolar and polar solvents, respectively. Time-dependent red-shift of emission spectra p-G2 both in c-Hex and DMF was observed in comparison with p-G1. Besides, the time constant of red-shift of spectra was found to be larger in DMF than in c-Hex. This indicates that the emissive state of p-G2 has a polar character in DMF as a result of charge delocalization from core to peripheral dendrons followed by stabilization of emissive state.

• 한국미생물·생명공학회지
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• 제30권3호
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• pp.253-257
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• 2002

쌀대신에 보리를 이용한 Monascus 고상배양의 기본적인 발효 특성을 연구함을 통하여, 대규모 고상배양 시스템을 통한 천연 적색색소의 생산 가능성을 검토하고자 하였다. 색소의 생산은 고상배양 3일후부터 6일까지 꾸준한 증가추세를 나타내었다. 종균의 접종량이 6∼8%사이일 경우에는 배양후 60시간만에 색소생산이 시작되었으며, 접종량이 5%이하일 경우에는 색소생산이 70시간 이후로 늦어지는 것으로 나타났다. 보리 배지를 30∼40분 동안 증자할 경우에는 색소 발현 시점이 45시간 내외로 단축되었으며, 증자시간이 20분 이하일 경우에는 배지의 불충분한 호화로 인하여 색소생산 시점이 길어졌다. 공기공급량이 0.6∼0.8 vvm사이에서 홍국균의 생장 및 색소의 생산이 활발히 일어났고, 고상배지의 초기 pH를 6으로 조절했을 때 균사성장과 색소발현 능력이 가장 우수하였다 한편 고상배양으로 7일동안 발효한 홍국보리를 사용하여 식중독미생물에 대한 항균여부를 확인한 결과, Escherichia coli, Salmonella 수Phimurium의 생장을 저해함을 확인하였다. 이상과 같이, 보리를 원료로 한 대규모 고상발효 시스템을 활용함으로써 Monascus sp. 유래의 천연색소 및 대사산물의 대량생산 가능성을 확인하였다.

• Journal of Ceramic Processing Research
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• 제20권1호
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• pp.80-83
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• 2019

The Mn4+-activated Li2ZnSn2O6 (LZSO:Mn4+) red phosphors were synthesized by the solid-state reaction at temperatures of 1100-1400 ℃ in air. The synthesized LZSO:Mn4+ phosphors were confirmed to have a single hexagonal LZSO phase without the presence of any secondary phase formed by the Mn4+ addition. With near UV and blue excitation, the LZSO:Mn4+ phosphors exhibited a double band deep-red emission peaked at ~658 nm and ~673 nm due to the 2E → 4A2 transition of Mn4+ ion. PL emission intensity showed a strong dependence on the Mn4+ doping concentration and the 0.3 mol% Mn4+-doped LZSO phosphor produced the strongest PL emission intensity. Photoluminescence emission intensity was also found to be dependent on the calcination temperature and the optimal calcination temperature for the LZSO:Mn4+ phosphors was determined to be 1200 ℃. Dynamic light scattering (DLS) and field-effect scanning electron microscopy (FE-SEM) analysis revealed that the 0.3 mol% Mn4+-doped LZSO phosphor particles have an irregularly round shape and an average particle size of ~1.46 ㎛.

• Horticulture, Environment, and Biotechnology : HEB
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• 제59권6호
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• pp.787-804
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• 2018

Flavor quality is import for determining consumer perception and acceptance of tomato products. In this study, 'Fendou' tomato fruit were harvested at six ripening stages and sampled to investigate the development of flavor-relevant compounds during vine ripening. Results showed that upon the initiation of ripening there was an increase in respiration rate and concomitant ethylene evolution that was associated with increased membrane permeability. In accordance with these physiological changes, flavor-relevant compounds demonstrated different expression patterns as fruit ripened, which contributed to 'red-ripe' flavor characteristics of red-ripe fruit. Based on correlation analysis between ethylene evolution and the flavor-relevant compounds during 'Fendou' tomato ripening and the other researchers' reports, the activation of System 2-dependent autocatalytic ethylene production plays an important role in the development of most flavor-relevant compounds during tomato vine ripening. Overall, our results suggested that most flavor-relevant compounds that accumulated the most during tomato fruit ripening at red stage could be under ethylene regulation and were among the most important contributors to the 'red-ripe' flavor. Due to the development of these compounds, the flavor quality at late ripening stages is different from that of fruit at early ripening stages.

• The Korean Journal of Pain
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• 제21권1호
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• pp.27-32
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• 2008

Background: Experimental evidence indicates that ginseng modulate the nociceptive transmission. Authors examined the role of adrenergic and cholinergic receptors on the antinociceptive action of Korean red ginseng against the formalin-induced pain at the spinal level. Methods: Catheters were inserted into the intrathecal space of male Sprague-DawIey rats. Fifty ${\mu}l$ of 5% formalin solution was injected to the hindpaw for induction of pain and formalin-induced pain (flinching response) was observed. The role of spinal adrenergic and cholinergic receptors on the effect of Korean red ginseng was assessed by antagonists (Prazosin, yohimbine, atropine and mecamylamine). Results: Intrathecal Korean red ginseng produced a dose-dependent suppression of the flinching response in the rat formalin test. All of prazosin, yohimbine, atropine and mecamylamine antagonized the antinociception of Korean red ginseng. Conclusions: Spinal Korean red ginseng is effective against acute pain and facilitated pain state evoked by formalin injection. All of alpha 1, alpha 2, muscarinic and nicotinic receptors may play an important role in the antinociceptive action of Korean red ginseng at the spinal level.