• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.847-851
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• 2000

In this study, contour-vibration-mode Pb($Ni_{1/2}$,$W_{1/2}$)$O_3$-Pb(Zr,Ti)$O_3$ piezoelectric transformers for driving a 28W(T5) fluorescent lamp were fabricated to the modified filter structure with ring and dot electrodes which has been developed for application in 455kHz AM radios. The piezoelectric transformers were fabricated to the size of $31.5$\times$31.5$\times$2.5$mm^3$ with the variations of ring/dot electrode area ratio. Driving of piezoelectric transformer was carried out with input region for the ring electrode and output region for the dot electrode. The electrical properties and characteristic temperature rises caused by the vibration were measured at various load resistances. A 28 W fluorescent lamp, T5, was successfully driven by the fabricated transformer. The transformer with ring/dot electrode area ratio of 1.83 exhibited the best properties in terms of output power, efficiency and characteristic temperature rise, 30.95 W, 97.57% and8.3$^{\circ}C$ respectively.

• 한국축산식품학회지
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• 제42권2호
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• pp.321-331
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• 2022

Egg yolk is widely used to extract lecithin, which is utilized in the food and cosmetics industry. After lecithin is removed, the rest of egg yolk is generated as a by-product. Thus, it is necessary to properly utilize it. In this study, egg yolk protein extracts were produced using ethanol (EYE-E) and water (EYE-W). Their antioxidant and immunomodulatory effects were then evaluated. Antioxidant activities of EYE-E and EYE-W were determined using cellular antioxidant capacity (CAC) assay and comet assay. EYE-E and EYE-W showed significant (p<0.05) scavenging effects on intracellular reactive oxygen species (ROS) in a dose dependent manner. At a concentration of 50 ㎍/mL, EYE-W showed higher (p<0.05) antioxidant activity than EYE-E. EYE-E and EYE-W also exhibited protective effects against DNA damage caused by oxidative stress. After treatment with EYE-E and EYE-W, DNA damage level of 48.7% due to oxidative stress was decreased to 36.2% and 31.8% levels, respectively. In addition, EYE-E and EYE-W showed immunomodulatory effects by regulating Th1 cytokines (TNF-α and IL-2) and Th2 cytokines (IL-10 and IL-4) in Balb/c mouse splenocytes. These data suggest that EYE-E and EYE-W could be used as functional food ingredients with excellent antioxidant and immunomodulatory activities in the food industry.

• Journal of Microbiology and Biotechnology
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• 제34권8호
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• pp.1636-1641
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• 2024

A Gram-stain-positive, aerobic, white-coloured, rod-shaped bacteria, designated as a strain dW9^T, was isolated from soil. Strain dW9^T was catalase-positive and oxidase-negative. Strain dW9^T grew at temperature of 20-37℃ and at pH of 5.0-7.0. Phylogenetic and 16S rRNA gene analysis indicated that strain dW9^T belonged to the genus Paenibacillus with its closest relative being Paenibacillus filicis S4^T (97.4% sequence similarity). The genome size of dW9^T was 7,787,916 bp with DNA G+C G+C content of 51.3%. The digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values of dW9^T with its closest relatives were found to be <22.0% and <74.0%, respectively. The only respiratory quinone was MK-7, and the major fatty acids were antiso-C_15:0 and iso-C_16:0. Overall, the comprehensive taxonomic analysis revealed that strain dW9^T met all the fundamental criteria to be classified as a novel species within the genus Paenibacillus. Accordingly, we propose the name Paenibacillus gyeongsangnamensis sp. nov., with the type strain dW9^T (=KCTC 43431^T =NBRC 116022^T).

• 한국전자통신학회논문지
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• 제7권5호
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• pp.1125-1131
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• 2012

농촌 노동력의 급격한 감소 및 고령화에 따라 저가의 농업로봇의 개발이 시급한 과제가 되어왔다. 본 논문에서는 농업용 방제 로봇의 H/W제어구조 및 S/W 플랫폼 개발에 대하여 기술한다. 개발된 로봇은 2 축의 캐터필러형 구동부와 2축의 방제기구 제어부를 구동부로 갖추고 있다. H/W 제어구조로써, 임베디드 XPE 기반 로봇 제어부, 원격 조종부, 그리고 센서 제어부로 구성된다. SW 플랫폼에서는 태스크 매니저, 원격 영상 및 데이터 통신을 위한 TCP-IP 통신 프로세스, 구동부 제어 프로세스, 위치 및 환경 인식 프로세스, 센서제어부 프로세스 등 5개의 프로세스가 동시에 동작한다. 개발된 농업용 원격 방제로봇을 필드테스트를 통하여 유용성을 시험하였다.

• 한국전자통신학회논문지
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• 제9권4호
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• pp.527-536
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• 2014

본 논문에서는 마이크로그리드 적용을 위한 50kW 풍력발전기를 설계하였으며, 발전기의 해석은 maxwell 2D 상용프로그램을 사용하였다. 특히 제안된 PMSG는 코깅토크를 줄이고자 offset과 skew를 적용하였다. 최적의 옵셋과 스큐는 2mm와 전기각 60도를 제안하였다. 부하운전시 모의결과는 평균 고조파 1.3%, 전압 322.41V, 전류 94.95A, 철손 9.73W, 와류손 73.68W, 동손 3.52kW로 나타났다. 계산된 발전기 용량은 61.56kW이며, 제안된 설계절차는 더 큰 용량의 발전기설계에 적용할 수 있다.

• 한국미생물·생명공학회지
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• 제31권4호
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• pp.383-388
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• 2003

가축 사료첨가용 효소생산을 목적으로 xylanase 및 CMCase를 동시에 분비하는 미생물을 분리한 후 가장 생산성이 높은 균주를 선발하였다. 선발된 미생물을 동정한 결과 Bacillus sp.에 속하는 균주로 Bacillus sp. A-7로 명명하였으며, B. licheniformis로 동정되었다. 효소생산을 위한 최적 액상배양조건은 탄소원으로 glucose 2.0%(w/v), 질소원으로 yeast extract 0.3%(w/v), 미네랄은 CaCl$_2$ 0.1% (w/v)인 것으로 나타났다. 저렴한 효소생산을 위한 배지조성을 얻기 위해 가축사료로 이용되는 저가의 원료사료를 이용하여 효소생산성을 파악한 결과 대두박 1.0%(w/v)와 당밀 0.5%(w/v)가 특히 xylanase 생산성이 높은 것으로 나타났다. 특히, 대두박 1.0%(w/v)를 기본배지로 하여 ammonium nitrate 0.3%(w/v) 및$ CaCl_2$ 0.1% 첨가가 적합한 배지조성으로 나타났다.

• 한국표면공학회지
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• 제28권4호
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• pp.207-218
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• 1995

Tungsten(W) metal has excellent properties in heat-resistance, corrison-resistance and impact-resistance but W-Metal is hard to sinter because higher than $2,000^{\circ}C$ is required to sinter W-powder. Con-sequently, a deposit technique of Nikel Phosphorus(NiP) on W-powber by the liquid reduction precipitation method was performed. Sintering temperature of the resulting W-NiP composite was lowered around to $1,000^{\circ}C$, and the mechanical properties of the sintered body was studied. The most suitable conditions for NiP thin film deposit on W-Powder by the liquid reduction precipitation method, which are composition, concentration, pH and temperature of the liquid reduction solution, were considered. The activated sintering was carried out in a reducing condition furnace. Components and properties of the sintered body were investigated by the density and the hardness measurements, X- ray diffraction analysis, and microscopic photographs of the surface. Quantity of NiP thin film on W-powder could be varied by the change of the liquid reduction solution composition. The sintering temperature of W-NiP composite powder is lowered to $950^{\circ}C$ from $2,000^{\circ}C$ and the hardness is increased (ca. 720 Hv). Large shrinkage could be observed since density was increased from 5.5 to 11.0 g/$cm^2$ which 86.2% of theoretical density. W metal and $Ni_3P$ crystal were detected through X-ray diffraction on the sintered body. Perfectly activated sintering was observed by microscopic photographs.

• 한국식품저장유통학회지
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• 제11권4호
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• pp.472-477
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• 2004

본 연구에서는 액상칼슘을 첨가하여 김치 숙성에 미치는 영향을 조사하였다. 그 결과 액상칼슘 첨가구들에서 숙성 중 pH감소가 지연되었고 산도는 더 낮게 나타났으며 액상칼슘 $3.5\%$ (v/w)첨가구보다 $7.0\%$ (v/w)첨가구에서 더 효과적이였다. 총균수 및 젖산균수를 조사한 결과 숙성 8일째까지 액상칼슘 첨가구들이 낮게 나타났으나 8일 이후에는 더 많은 수를 나타내었다. 모든 구간에서 L값과 b값은 조금씩 감소하였으며 a값은 증가하는 경향으로 나타났다. 대조구의 칼슘함량은 $50{\sim}60\;mg\%$이며 액상칼슘 A 농도 $3.5\%$ (v/w)와 $7.0\%$ (v/w) 첨가구에서 $103{\sim}110\;mg\%$와 $145{\sim}163\;mg\%$로 액상칼슘 B 농도 $3.5\%$ (v/w)와 $7.0\%$ (v/w) 첨가구에서는 $140{\sim}151\;mg\%$ 및 $210{\sim}220\;mg\%$으로 나타나 액상칼슘 B를 $7.0\%$ (v/w) 첨가하면 고칼슘 김치의 제조가 가능한 것으로 생각되었다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 춘계종합학술대회
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• pp.410-413
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• 2003

고출력 레이저광 출력측정 및 교정을 위한 계측 장치를 제작하고 성능 평가에 관한 연구를 수행하였다. 계측 장치의 수광부는 금 코팅된 구리재질의 공동을 사용하여 제작되었다. 교정용 히터는 망가닌으로 제작되고, 출력 측정은 망가닌과 구리의 저항 브릿지를 사용하여 측정하였다. 외부 환경의 영향을 줄이기 위해 칼로리미터 내부의 온도를 5mK이하로 일정하게 하였다. 고출력 레이저 에너지의 측정을 위해 교정 인자와 보정 계수를 측정을 통하여 구하였다. 교정 인자는 100W 범위에서 489.13 J/mV 이고 500W 범위에서 497.04 J/mV이다. Nd:YAG Laser를 이용하여 보정 계수를 구한 결과 100W범위일 때는 0.99이고 500W범위일 때는 1.006으로 레이저 에너지와 전기적 교정의 차이는 1%이하이다.

• 대한수의학회지
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• 제11권2호
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• pp.145-148
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• 1971

Serum Samples from adult of Korean cattles including 40 females and 20 males were analyzed by sodium salt precipitation and colorimetric method in the purpose of the determination of total serum protein, albumin, globulin, ${\alpha}$-globulin, ${\beta}$-globulin and ${\gamma}$-globulin. The results obtained arc summarized as follows: 1. Mean value of total serum protein showed a slight variation from 7.6%, and its regional and sex differences were not found to be significant. 2. Contents of albumin in serum showed lower level than that of globulin as low level of A/G ratio 0.4 in proportion. 3. Contents of Serum ${\alpha}$-globulin showed 1.4w/v% and $1.51{\pm}0.46$w/v% in each group of female, and $1.31{\pm}0.26$w/v%, in the group of male. 4. Contents of serum ${\beta}$-globulin showed 1.74w/v%, 1.95w/v%, in each group of female, and 1.82w/v% in the group of male. 5. Contents of serum ${\gamma}$-globulin showed 2.32w/v%, 2.30w/v% in each group of female, and 2.30w/v%, in the group of male.