• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 한국식품영양학회 2003년도 하계 학술 심포지엄
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• pp.80-80
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• 2003

가열살균 처리시의 온도값을 이용하여 다양한 미생물들의 가열살균 효과를 D값, z값 등의 미생물 내열성 특성치와 kinetic 모델 및 수식을 이용하여 살균치 계산을 컴퓨터를 이용하여 수행함으로써 target 미생물의 살균정도를 예측하고자, Excel과 Visual Basic을 연동하여 작성된 시스템으로 Excel을 기본으로 사용한 프로그램을 개발하였다. 가열살균 target 미생물을 선택하고자 야채식품을 기반으로 하는 식품에서의 미생물을 검토하여, 내열성인 가장 큰 호기성 포자형성균인 Bacillus spp. 계통이 산을 형성하여 맛 등의 품질을 저하시켜 변패를 유발하며, 위생적인 면에서 포자수를 줄이거나 사멸할 필요가 있어서 선택하였다. 병원성 균 중에서 D121.1이 0.0065분, z값이 7.8$^{\circ}C$인 Bacillus cereus와 부패현상 관련 균 중에서 D121.1이 0.5분, z값이 12$^{\circ}C$인 Bacillus subtilis를 대상으로 해서 개발되었으며, 필요시에는 D값과 z값을 직접 대입하므로서, 여러 가지 미생물에 대해서도 적용이 가능하게 하였다.

• Proceedings of the Korean Vacuum Society Conference
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.179.1-179.1
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• 2013

Cylindrical Rotating Magnetron Sputtering Cathode (이하 Rotary Cathode)는 기존에 사용 되던 rectangular type 보다 Target 사용 효율이 높다는 큰 이점을 가지고 있다. 높은 Target 사용 효율은 비용 절감 효과와 직접적으로 관련 된다. 이번 연구는 3D Plasma simulation(PIC-MCC)을 통한 Target 사용 효율 80% 이상의 Rotary Cathode 개발을 목적으로 한다. Plasma simulation에 External Magnetic fields를 접목하여 Electron의 이동 궤적을 제어하였고, 생성된 Ion (Ar+)의 밀도 및 속도로 Plasma의 안정성과 Erosion 계산 구간을 선정 하였다. Target Erosion Profile은 Sputtering yield Data와 Target에 충돌한 Ion 정보를 사용하여 산출 하였으며, Sputtered Particles의 Deposition Profile은 계산된 Target Erosion Profile과 The cosine law of emission을 이용하여 계산 하였다. 실험 조건은 Plasma simulation의 초기조건 바탕으로 하여 2G size의 ITO Target을 대상으로 실험 하였다. 비 Erosion 영역 최소화하기 위해 Magnet Length를 변경하여 제작 적용 하였다. Simulation 계산 시간의 제약으로 인하여 simulation에서 생성된 최대 이온 밀도는 일반적으로 알려진 값 보다 적게 계산 되었지만, Simulation으로 예측한 Erosion Profile 및 Deposition Profile은 실험 값과 유사한 형태를 나타났으며, 실험 결과는 Target 사용 효율 80%이상의 결과를 보였다.

• Journal of Korean Clinical Health Science
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• 제11권1호
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• pp.1616-1624
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• 2023

Purpose. The purpose of this study was to investigate the effect of changes in tear break-up time, accommodative response amount, and accommodative microwave on the eyes due to changes in humidity. Methods. A total of 48 adult men and women in their 20s (21.1±1.56 years old) were surveyed on dry eye questionnaires (OSID questionnaires), tear destruction time was measured by humidity (40%, 60%, 80%), and controlled reactions and controlled fine waves were measured through tactile tests. Result. As a result of the OSID questionnaire, there were 10 normal patients, 8 mild dry eyes, 1 moderate dry eye, and 5 severe dry eyes. The initial tear film destruction time was 7.34±4.67 seconds at 40% humidity, 8.99±4.75 seconds at 60% humidity, 10.26±4.52 seconds at 80% humidity, and the average tear film destruction time was 9.51±4.07 seconds at 40% humidity, 10.99±3.82 seconds at 60% humidity, and 12.05±3.42 seconds at 80% humidity. The accommodative response was -0.41~1.79D at 40% humidity, -0.34~1.79D at 60% humidity, and -0.30~2.01D at 80% humidity. The accommodative microwave was measured as 56.39~63.43dB when it was 40%, 56.41~62.64dB when it was 60%, and 55.96 ~61.13dB when it was 80%. Conclusion. As the humidity (40~80%) increased, the tear break-up time increased, and as the accommodative stimulus amount increased, the accommodative response amount increased. It was found that the accommodative microwave according to the amount of accommodative stimulation increased, and as the humidity increased, the accommodative microwave decreased.

• The Journal of Korean Institute of Communications and Information Sciences
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• 제40권12호
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• pp.2461-2468
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• 2015

Sinuous antenna is utilized in a number of application like direction-finding system that require ultra wideband, but because of high input impedance of the antenna, it is difficult to design low-profile antenna and balun. In this study, we used Babinet's principle and proposed linear 2-arm slot sinuous antenna that is divided sinuous 6 cell with equal spacing between the most largest radius $R_1=31.83mm$ and the smallest radius $R_p=1.7mm$ instead of exponential 2-arm strip sinuous antenna for 2-18[GHz] frequency band to obtain low input impedance, and we have studied -10dB bandwidth of antenna when has been fed by $80{\Omega}$ instead of $188{\Omega}$ at feeder point. As a result, we have obtained return loss below than -10dB for about 4-18[GHz] frequency range in the case of slot antenna, but at all frequency band, return loss was above -10dB in the case of strip antenna.

• Proceedings of the IEEK Conference
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(2)
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• pp.12-15
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• 2000

In this paper, we have fabricated the PHEMT's with AlGaAs/InGaAs/GaAs and measured characteristics of DC and frequencies. The PHEMT's has a 0.35$\mu\textrm{m}$ gate length, gate width of 60$\mu\textrm{m}$ and 80$\mu\textrm{m}$, and fingers of 2 and 4. From the measurements results for the 60$\mu\textrm{m}$ ${\times}$ 2 PHEMT's, we obtained 1.2V of Vk, -3.5V of Vp, 46mA of Idss, 221mS/mmof gm, and 3.6dB of S$\sub$21/ gain, 45GHz of f$\sub$T,/ 100GHz of fmax. And, in case of 80$\mu\textrm{m}$ ${\times}$ 4 PHEMT's, we obtained 1.2V of Vk, -4.5V of Vp, 125mA of Idss, 198mS/mm of gm, and 2.0dB of S$\sub$21/ gain. 44GHz of f$\sub$T/, 70GHz of fmax at 35GHz frequency. Also, MAG are decreased as a number of finger are Increased.

• ALGAE
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• 제19권4호
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• pp.303-309
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• 2004

The laboratory culture study of Porphyra seriata Kjellman from Korea was conducted at different conditions of temperatures (5, 10, 15, 20, 25 and 30${^{\circ}C}$), photon flux densities (10, 20, 40 and 80 $\mu$mol $^{-2}s^{-1}$) and photoperiods (14L: 10D and 10L:14D). Conchocelis filaments grew fast at 15-20${^{\circ}C}$ and 20-80 $\mu$mol $^{-2}s^{-1}$ under both photoperiods. Concho sporangial branches were produced at 5-25${^{\circ}C}$, and abundant when the conchocelis filaments were cultured at higher temperatures of 20-25${^{\circ}C}$ under both photoperiods. Foliose thalli grew well at 15-20${^{\circ}C}$ under 10L:14D and at 20${^{\circ}C}$ under 14L:10D. At 30${^{\circ}C}$, the foliose thallus failed to survive. No archespores were observed at any culture conditions. Spermatangia and zygotosporangia were formed in squarish patches at the upper marginal portion of mature thalli. Anatomical examination revealed that the mature spermatangia were 64 (a/4, b/2, c/8) and 128 (a/4, b/4, c/8), and that of zygotosporangium was 16 (a/2, b/2, c/4) according to the Hus' formula.

• Journal of Applied Biological Chemistry
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• 제61권2호
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• pp.131-134
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• 2018

The stem of Chrysanthemum morifolium, 'Baekma', were repeatedly extracted with 80% aqueous MeOH and the concentrates was partitioned into ethyl acetate (EtOAc), n-butyl alcohol and $H_2O$ fraction. The repeated silica gel and octadecyl silica gel column chromatographies for the EtOAc fractions led to isolation of two glycosyl glycerides. The chemical structures of the compounds were determined as (2S)-1-O-${\beta}-{\text\tiny{D}}$-galactopyranosyl-2,3-dilinoleoylglycerol (1) and (2S)-1-O-${\beta}-{\text\tiny{D}}$-galactopyranosyl-2,3-dipalmitoylglycerol (2) based on spectroscopic data anlyses including nuclear magnetic resonance, mass sperctrometry, and infrared spectrometry and gas chromatography mass spectrometry.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• 제27권1호
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• pp.92-95
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• 2016

In this paper, an UHF-band 1 kW solid-state pulsed power amplifier was designed and implemented for the thermoacoustic imaging(TAI) at 900 MHz. The designed power amplifier has a pulse width of $80{\mu}s$ and a duty cycle of 1 % for short-pulse operation. The overall amplifier was implemented by combining of 16 single-power amplifiers adopting MRFE6P9220HR3 LDMOSFET using wilkinson power dividers. The solid-state pulsed power amplifier shows 25 % drain efficiency with a gain of 76.2 dB when the output power is 60.2 dBm for a -16 dBm input power at center frequency.

• Advances in Traditional Medicine
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• 제10권4호
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• pp.319-321
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• 2010

Plant saponins are widely distributed amongst plants and have a wide range of biological properties. Icosahydropicenic acid, $C_{51}H_{80}O_{19}$ ((4S,6bS)-8a-((4,5-dihydroxy-6-methyl-3-((3R)-3,4,5-trihydroxy-6-methyl-tetrahydro-2H-pyran-2-yloxy)-tetrahydro-2H-pyran-2-yloxy)carbonyl)-2-hydroxy-4, 6a, 6b, 11, 14b-pentamethyl-11-(2-methylprop-1-enyl)-3-(3,4,5-trihydroxy-6-(hydroxymethyl) - tetrahydro-2Hpyran-2-yloxy)-1, 2, 3, 4, 4a, 5, 6, 6a, 6b, 7, 8, 8a, 9, 10, 11, 12, 12a, 14, 14a, 14b-icosahydropicene-4-carboxylic acid), a new saponin was first time isolated from the roots of Clerodendrum Serratum (L) Moon (Verbenaceae). The structure elucidation of the compound was carried out by $^1H$ NMR and DART-MS studies.

• Korean journal of applied entomology
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• 제20권1호
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• pp.37-41
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• 1981

Mycelial growth and production of macroconidia by Cylindrocladium crotalariae on either PDA or water agar containing soybean leaf pieces adjusted to different water potentials with KCI. were consistently maximal at -14bars. Mycelial growth by this fungus was nii at about -100 bars and below at 30C, -80 bars and below at 25C and -64 bars and below at 20C. Sporulation was prevented at -64 bars and below at $20^{\circ}C\;and\;25^{\circ}C$. Perithecial andmicrosclerotial formation was maximal at abot -1.4 to - 3.0 bars (the basal medium without sait). Percentage of spore germination for this fungus was uniformly maximal at all water potentials between -1.4 bars (the highest tested) and - 20 bars, was progressively less as the water potential lowered below -20 bars, and was prevented at - 60 bars.