• 공업화학
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• 제17권5호
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• pp.517-520
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• 2006

망간산화물과 아연이 혼재되어 있는 폐알카리 망간전지로부터 황산용액에서 환원제로 과산화수소를 이용하여, 침출제 농도, 온도, 반응시간, 과산화수소의 양 등을 변화시키면서 망간과 아연의 침출거동을 조사하였다. 그 결과 고액농도 100 g/L, 황산농도 3.0 M, 반응온도 $60^{\circ}C$, 교반속도 200 r.p.m. 그리고 과산화수소를 첨가하지 않은 조건에서 아연과 망간의 침출율은 각각 97.7 %와 43.5 %를 나타내었으나, 반응온도 $60^{\circ}C$에서 과산화수소 30 mL를 첨가하였을 때는 아연과 망간의 침출율은 각각 99.6 %와 97.1%를 나타내어 환원제를 첨가하지 않은 조건보다 망간의 침출율이 약 2배 정도 증가하였다. 그러나 과산화수소 양이 30 mL 이상에서는 첨가되는 과산화수소의 양이 증가하여도 아연과 망간의 침출율의 변화는 거의 없었다.

• BMB Reports
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• 제30권1호
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• pp.46-54
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• 1997

Alkaliphilic Bacillus sp. S-1 secretes a large amount (approximately 80% of total pullulanase activity) of an extracellular pullulanase (PUL-E). The pullulanase exists in two forms: a precursor form (PUL-I: $M_r$ 180,000), and a processed form (PUL-E: $M_r$ 140,000). Two forms were purified to homogeneity and their properties were compared. PUL-I was different in molecular weight, isoelectric point, $NH_2$-terminal amino acid sequence, and stabilities over pH and temperature ranges. The catalytic activities of PUL-I were also distinguishable in the $K_m$ and $V_{max}$ values for various substrates, and in the specific activity for pullulan hydrolysis. PUL-E showed 10-fold higher specific activities than PUL-I. However. PUL-I is immunologically identical to PUL-E, suggesting that PUL-I is initially synthesized and proteolytically processed to the mature form of PUL-E. Processing was inhibited by PMSF, but not by pepstatin, suggesting that some intracellular serine proteases could be responsible for processing of the PUL-I. PUL-I has a different conformational structure for antibody recognition from that of PUL-E. It is also postulated that the translocation of alkaline pullulanase(AP) in the bacterium possibly requires processing of the $NH_2$-terminal region of the AP protein. Processing of the precursor involves a conformational shift. resulting in a mature form. Therefore. precursor processing not only cleaves the signal peptide, but also induces conformational shift. allowing development of active form of the enzyme.

• 한국식품저장유통학회지
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• 제30권3호
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• pp.369-382
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• 2023

We examined the changes in the physicochemical quality characteristics and antioxidant activity of fresh-cut Fuji apples (Malus pumila) during processing and storage after treatment with browning inhibitors. The primary aim was to elucidate processing suitability and storability. We observed that in the processing stage of slicing fresh Fuji apples, there were no significant differences in 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging ability and ferric-reducing antioxidant power (FRAP). However, after NaClO treatment, total flavonoid and total polyphenol contents decreased. When freshcut Fuji apples were treated with browning inhibitors and stored at 4℃, the L value and hardness decreased; however, the weight loss rate increased based on the storage period of all fruit groups treated with Citrus unshiu Markovich (CuM), calcium ascorbate (CA), and ascorbic acid (AA). The pH increased after 2 days of storage in 1% CuM and after 6 days of storage in 1% CA; however, no changes in pH were observed during the storage period in 1% AA. The DPPH radical scavenging activity was generally good under storage conditions of 1% AA at 4℃ and 1% CA at 20℃. Furthermore, FRAP remained relatively constant under storage conditions of 1% CA. The quality characteristics and antioxidant activity of fresh-cut fruits during processing and storage can be used as basic data for industries. Furthermore, we can gain confidence in quality improvements by improving the production and distribution environment of fresh-cut agricultural products.

• ETRI Journal
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• 제37권3호
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• pp.523-532
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• 2015

Recently, we have witnessed the gradual miniaturization of electronic devices. In miniaturized devices, flip-chip bonding has become a necessity over other bonding methods. For the electrical connections in miniaturized devices, fine-pitch solder bumping has been widely studied. In this study, high-volume solder-on-pad (HV-SoP) technology was developed using a novel maskless printing method. For the new SoP process, we used a special material called a solder bump maker (SBM). Using an SBM, which consists of resin and solder powder, uniform bumps can easily be made without a mask. To optimize the height of solder bumps, various conditions such as the mask design, oxygen concentration, and processing method are controlled. In this study, a double printing method, which is a modification of a general single printing method, is suggested. The average, maximum, and minimum obtained heights of solder bumps are $28.3{\mu}m$, $31.7{\mu}m$, and $26.3{\mu}m$, respectively. It is expected that the HV-SoP process will reduce the costs for solder bumping and will be used for electrical interconnections in fine-pitch flip-chip bonding.

• Asian-Australasian Journal of Animal Sciences
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• 제15권6호
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• pp.872-877
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• 2002

Two experiments were conducted to determine the effects of reducing particle size of corn from 1,000 to 500 ${\mu}m$ in simple and complex diets for nursery pigs and broiler chicks. In Exp 1., 192 nursery pigs were used in a 24 d growth assay. Treatments were: 1) 1,000 ${\mu}m$ corn in a simple diet; 2) 500 ${\mu}m$ corn in a simple diet; 3) 1,000 ${\mu}m$ corn in a complex diet; and 4) 500 ${\mu}m$ corn in a complex diet. Overall, pigs fed complex diets had 9% greater ADG (p<0.005) and 5% greater gain/feed (p<0.01) compared to pigs fed simple diets. Also, pigs fed the 500 ${\mu}m$ treatments had 3% better overall gain/feed than those fed the 1,000 ${\mu}m$ treatments (p<0.007). At d 9, apparent digestibilities of DM, N and GE were greater for complex diets and diets with smaller particle size (p<0.02). At d 23, there were no differences in nutrient digestibility resulting from diet complexity, but pigs fed diets with corn ground to 500 ${\mu}m$ had greater digestibility of DM (p<0.02) and GE (p<0.003) than pigs fed diets with corn ground to 1,000 ${\mu}m$. A second experiment was designed to determine if four days old broiler chicks were an acceptable model for predicting the effects of feed processing procedures on nursery pigs. Chicks fed complex diets had 3% greater gain/feed than chicks fed simple diets (p<0.001). Rate of gain and feed intake were improved by 3 and 2%, respectively, for chicks fed crumbled diets (p<0.03). However, there were several significant interactions among the main effects. For instance, crumbling did not affect gain/feed in chicks fed complex diets, but rate of gain and feed intake were increased by 7 and 6%, respectively, when simple diets were crumbled (diet complexity${\times}$diet form, p<0.001). Also, gain/feed of chicks was improved by 3% when particle size was reduced in meal diets, but not affected in chicks fed crumbles (diet form${\times}$particle size, p<0.005). Thus, our data suggested that reduction of particle size of corn was important for simple and complex diets and that a complex diet with 1,000 ${\mu}m$ corn gave no better performance than a simple diet with 500 ${\mu}m$ corn.

• 환경영향평가
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• 제28권6호
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• pp.549-555
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• 2019

본 연구의 목적은 기능성 여재를 활용하여 부영양화의 원인 물질인 인(P)과 질소(N)의 제거효율을 향상 시킬 수 있는 최적의 운전 조건을 확보하기 위함이다. 본 연구에 사용된 기능성 여재의 주성분이 Si, Al, 및 Fe 이고, 석영(SiO₂), 정장석(KAlSiO₃O₈), 할로이사이트(Al₂O₃·2SiO₂), 카올린(H₃Al₂Si₂O₉), 자철석(Fe₃O₄), 버미큐라이트 등이 함유되어 있다. 여과공정의 최대 효율성을 파악하기 위해 흐름방식, 선속도, 여재두께에 따른 처리효율 실험을 진행하였다. 흐름방식은 상향류 및 하향류 조건의 두 가지 실험을 진행하였고, 선속도는 50 m/day, 100 m/day, 150 m/day, 200 m/day, 250 m/day의 조건, 여재두께는 20 cm, 40 cm, 50 cm, 60 cm, 80 cm의 조건에서 실험을 진행 하였다. 실험 결과 SS, T-N, T-P 모두 상향류 조건이 하향류 조건보다 높은 제거효율을 보였고, 선속도별 처리 효율은 SS 50 m/day, T-N 150 m/day, T-P 100 m/day에서 가장 높은 효율을 보이는 것으로 나타났다. 또한 여재두께에 따른 제거효율 분석 결과 SS, T-N, T-P 모두 60 cm에서 가장 높은 효율을 보이는 것으로 나타났다. 최적의 조건은 상향류 조건 및 60cm의 여재 두께를 설정하고 제거 목표 물질에 따라 선속도를 조절하여 처리 하는 것이 바람직하다고 사료된다.

• 한국건축시공학회지
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• 제18권3호
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• pp.277-283
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• 2018

공기를 획기적으로 감소시킬 수 있는 모듈러건축으로 유사 모듈이 반복되는 공동주택을 건설하는 안에 대해 현행의 시공방법을 고찰한 결과 설비시스템에서 개선할 점을 발견하고, 그 방법으로 공장제작과 현장설치부분을 구분해서 살펴보고 현재 모듈러생산사 실무진의 의견과 종합건설사 기술담당자의 의견으로 그 가능성을 확인하고자 했으며 그 과정에서 제기된 문제에 대해 원천적인 관점에서 쉽게 풀어나갈 수 있는 방법으로 유리한 설계안을 제안하였고, 접속부위의 누수하자와 같은 고질적 문제점에 대한 대안을 기재하였다.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2012년도 추계학술발표대회
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• pp.954-957
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• 2012

Recent high profile attacks have brought the attention of governments, corporations, and the general public towards the dangers posed by Advanced Persistent Threats. This paper provides an analysis of the attack vectors employed by these actors by studying several recent attacks. We present recommendations on how to best defend against these threats by better classification of critical information infrastructure and assets, people protection, penetration tests, access control, security monitoring, and patch management.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2008년도 추계학술발표대회
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• pp.730-733
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• 2008

원자력 발전소 정보 관리 시스템인 GPM 시스템에서 원자력 발전소 유지보수 프로세스에서 발생하는 도면, 문서 등 데이터와 비즈니스 프로세스를 모델링한 데이터 모델을 범용 제품 모델 (GPM, Generic Product Model) 클래스 라이브러리에 통합하였다. 이를 통해 제시하는 표준 데이터 모델은 지능적 P&ID 시스템의 기본 데이터 모델로 사용될 수 있으며, 이를 기반으로 향후에는 지식화된 정보 서비스 제공이 가능하게 된다.

• 한국식품영양학회지
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• 제21권4호
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• pp.524-529
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• 2008

The principal objective of this study was to conduct a physiological evaluation of Korean Ginseng pickles with added Chija and Omija pigment. Prior to the processing of 3 different colors of pickles, SOD-liked activity, hydroxyl radical scavenging activity, total phenolic acid contents, and lecithin oxidation inhibitory effects of Korean Ginseng, Chija and Omija water extracts were assessed. After processing the 3 colors of pickles, sensory evaluation and color values were conducted. SOD-liked activity of Korean Ginseng(42.58%) and Chija(41.88%) water extracts were similar to those of tocopherol(54.62%), but were significantly higher than those of Omija(29.01%). The hydroxyl radical scavenging activity of Ginseng water extract(87.85%) was similar to that of BHT(83.13%) and tocopherol(71.57%), but were significantly higher than those of Chija(68.01%) and Omija(37.15%). The total phenolic acid contents of Korean Ginseng, Chija, and Omija water extracts were measured at $1.01{\sim}1.66\;mg/m{\ell}$, levels similar to those of tocopherol($1.26\;mg/m{\ell}$) but significantly lower than that of BHT($3.89\;mg/m{\ell}$)(p<0.05). The lecithin oxidation inhibitory effects of Ginseng water extract(98.86%) was similar to that of BHT(92.82%) and tocopherol(89.13%), but was significantly higher than that of Chija(64.28%) and Omija (53.34%). With regard to the results of sensory evaluation for the 3 colors of Ginseng pickles, the color and overall quality of P2 were significantly higher than those of P1 and P3(p<0.05). With regard to luminance, P1 scored significantly higher than P2 and P3(p<0.05). The a value of P3 was significantly higher than that of P1 and P2, and the b values of P2 were significantly higher than those of P1 and P3.