• 한국비블리아학회지
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• 제30권1호
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• pp.101-119
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• 2019

이 연구는 한국의 도서관과 기록관이 자연 재난 대비 계획을 수립하는 데 참고해야 하는 핵심 요소 검토를 목적으로 진행하였다. 국내에서는 그간 도서관과 기록관의 자연 재난 대비 계획과 관련한 연구가 충분히 진행되지 않았기 때문에 국외에서 폭넓게 진행된 선행연구를 조사하고 분석하였다. 그 결과 국외 연구에서 공통으로 확인되는 재난 대비 계획수립을 위한 핵심 요소는 크게 6가지로 종합할 수 있었다. 먼저 재난 대비 계획의 시작을 위해서 '재난 대비 위원회가 조직되고 업무가 분담'되어야 하며, 재난에 취약한 '위험은 미리 평가되고 관리' 되어야 한다. 또한 모든 직원이 재난 발생 시 '즉각적으로 대응하기 위한 핸드북'이 마련되어야 하며, 재난 발생 후 재난 규모에 따른 전략적 복구와 업무 복귀를 위한 '복구 및 업무 연속성 계획'이 검토되어야 한다. 그리고 직원의 재난 대처 역량과 재난 대비 계획을 강화하기 위해서 '훈련'이 필요하며, 재난 대비에 관한 다양한 관점을 확보하고 대규모 재난 대응과 복구 대비를 위해서 관련 기관 간 '협력 활동'도 고려되어야 한다. 이 논문이 향후 국내 도서관과 기록관의 재난대비 계획수립 검토에 일조하기를 기대한다.

• 한국전기전자재료학회논문지
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• 제31권5호
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• pp.345-350
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• 2018

Nanomaterials have considerable potential to solve several key challenges in various electrochemical devices, such as fuel cells. However, the use of nanoparticles in high-temperature devices like solid-oxide fuel cells (SOFCs) is considered problematic because the nanostructured surface typically prepared by deposition techniques may easily coarsen and thus deactivate, especially when used in high-temperature redox conditions. Herein we report the synthesis of a self-regenerated Pd metal nanoparticle on the perovskite oxide anode surface for SOFCs that exhibit self-recovery from their degradation in redox cycle and $CH_4$ fuel running. Using Pd-doped perovskite, $La(Sr)Fe(Mn,Pd)O_3$, as an anode, fairly high maximum power densities of 0.5 and $0.2cm^{-2}$ were achieved at 1,073 K in $H_2$ and $CH_4$ respectively, despite using thick electrolyte support-type cell. Long-term stability was also examined in $CH_4$ and the redox cycle, when the anode is exposed to air. The cell with Pd-doped perovskite anode had high tolerance against re-oxidation and recovered the behavior of anodic performance from catalytic degradation. This recovery of power density can be explained by the surface segregation of Pd nanoparticles, which are self-recovered via re-oxidation and reduction. In addition, self-recovery of the anode by oxidation treatment was confirmed by X-ray diffraction (XRD) and scanning electron microscopy (SEM).

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.210-213
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• 2008

The purpose of this study is to investigate the performances of organic removal and methane recovery in the full scale two-phase anaerobic system. The full scale two-phase anaerobic system was consists of an acidogenic ABR (Anaerobic Baffled Reactor) and a methanognic UASB (Upflow Anaerobic Sludge Blanket) reactor. The volume of acidogenic and methanogenic reactors is designed to 28.3 $m^3$ and 75.3 $m^3$. The two-phase anaerobic system represented 60-82% of COD removal efficiency when the influent COD concentration was in the range of 7,150 to 16,270 mg/L after screening (average concentration is 10,280 mg/L). After steady-state, the effluent COD concentration in the methanogenic reactor showed 2,740 $\pm$ 330 mg/L by representing average COD removal efficiency was 71.4 $\pm$ 8.1% when the operating temperature was in the range of 19-32$^{\circ}C$. The effluent SCOD concentration was in the range of 2,000-3,000 mg/L at the steady state while the volatile fatty concentration was not detected in the effluent. Meanwhile, the COD removal efficiency in the acidogenic reactor showed less than 5%. The acidogenic reactor played key roles to reduce a shock-loading when periodic shock loading was applied and to acidify influent organics. Due to the high concentration of alkalinity and high pH in the effluent of the methanogenic reactor, over 80% of methane in the biogas was produced consistently. More than 70 % of methane was recovered from theoretical methane production of TCOD removed in this research. The produced gas can be directly used as a heat source to increase the reactor temperature.

• 한국정보통신학회논문지
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• 제5권3호
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• pp.419-425
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• 2001

이동통신에서 다중경로에 의한 페이딩 현상은 시스템의 성능에 영향을 주는 큰 원인 중의 하나이다. 이런 페이딩 채널에서의 성능저하를 개선하기 위하여 많은 연구가 진행되고 있다. 채널 페이딩을 추정하여 보상하는 방식에서는 파일럿 심벌을 이용하는 PSAM(pilot symbol assisted modulation) 방식이 널리 이용되고 있으며 TCM(trellis-coded modulation)은 전송 대역폭의 증가 없이 철저한 부호화 이득을 얻을 수 있는 부호화와 변조 과정이 결합된 전송 기술이다. 본 논문에서는 주파수 비선택적 레일리 페이딩 채널에서 PSAM과 TCM을 사용하는 PSA-TC-8PSK의 성능을 분석하였다. 페이딩의 추정을 위한 보간 방법에는 오차의 분산을 최소화하는 Wiener 필터를 사용하였으며 필터의 탭수, 파일럿 심벌 주기, 도플러 주파수가 성능에 미치는 영향을 분석하였다. 또한 완전 디지털 방식의 구현이 가능한 심벌 타이밍 복구 회로를 구성하여 심벌 타이밍 에러가 전체 성능에 미치는 영향을 분석하였다.

• 에너지공학
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• 제21권3호
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• pp.315-324
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• 2012

폐기물 저감 재활용 에너지화 기술은 27대 중점 녹색기술 중 하나로, 2012년까지 정부 R&D 투자가 증가해야 함에도 불구하고, 2008년~2010년 기간 동안 연평균 증가율이 오히려 감소하였다. 이에 따라 동 분야의 정부 R&D 투자 현황을 상세히 분석하였고, 그 결과 총 정부 R&D 투자는 감소하였지만, 동 분야에서 정의하는 전략제품 서비스 기술에 대한 투자는 증가하고 집중화 되는 추세로 나타나 투자의 질적인 측면은 양호했다고 판단된다. 특히 2010년에는 전략제품 서비스 기술 중 3개 기술군((1) 폐기물 에너지화설비, (2) 폐기물자원순환시설, (3) 폐기물기반 물질생산시설)의 비중이 24 ~ 28%로 비교적 균등하게 투자되어, 정부 R&D 투자는 질적으로 적절했다고 판단되어 진다. 이러한 분석틀은 향후 녹색기술 R&D 정책 추진점검에서 활용할 수 있을 것이다.

• Ocean and Polar Research
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• 제27권4호
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• pp.451-461
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• 2005

The $CO_2$ storage in geologic and oceanic reservoirs is considered to be one of the carbon management strategies for responding to global climate change. Ocean carbon sequestration is purposeful storage acceleration into the ocean of large amounts of carbon that would accumulate in the atmosphere and naturally enter the ocean over a longer timespan. Some technologies for $CO_2$ ocean sequestrations have been developed as a nation project. However, $CO_2$ ocean sequestrations are attractive because they have the advantage of vast capacity sequestration far away from industrial areas, and offer easier monitoring whereas less economic advantage has been indicated as one of the key barriers compared with $CO_2$ geosphere sequestration, which is produced as a byproduct. In this paper, a conceptual design for $CO_2$ ocean sequestration is introduced, and the preliminary examination is described. As a result, the $CO_2$ price, US$ 24/t shows far away from the economics. The causes come from the expensive $CO_2$ recovery cost and the low $CO_2$ price. The expensive $CO_2$ recovery cost is because too much electricity and water are consumed. In order to look for an economic balance point for $CO_2$ ocean sequestration, NPV=0, it is increases the $CO_2$ price. Finally 60.4$ per ton is found to be the balance price.

• Journal of Microbiology and Biotechnology
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• 제26권11호
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• pp.1871-1880
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• 2016

Bio-oxidation is an effective technology for treatment of refractory gold concentrates. However, the unsatisfactory oxidation rate and long residence time, which cause a lower cyanide leaching rate and gold recovery, are key factors that restrict the application of traditional bio-oxidation technology. In this study, the oxidation rate of refractory gold concentrates and the adaption of microorganisms were analyzed to evaluate a newly developed two-step pretreatment process, which includes a high temperature chemical oxidation step and a subsequent bio-oxidation step. The oxidation rate and recovery rate of gold were improved significantly after the two-step process. The results showed that the highest oxidation rate of sulfide sulfur could reach to 99.01 % with an extreme thermophile microbial community when the pulp density was 5%. Accordingly, the recovery rate of gold was elevated to 92.51%. Meanwhile, the results revealed that moderate thermophiles performed better than acidophilic mesophiles and extreme thermophiles, whose oxidation rates declined drastically when the pulp density was increased to 10% and 15%. The oxidation rates of sulfide sulfur with moderate thermophiles were 93.94% and 65.73% when the pulp density was increased to 10% and 15%, respectively. All these results indicated that the two-step pretreatment increased the oxidation rate of refractory gold concentrates and is a potential technology to pretreat the refractory sample. Meanwhile, owing to the sensitivity of the microbial community under different pulp density levels, the optimization of microbial community in bio-oxidation is necessary in industry.

• 한국전문물리치료학회지
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• 제27권1호
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• pp.63-69
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• 2020

Background: Stroke recovery is a long and complex process. Successful stroke recovery seems to be strongly associated with patients' high motivation and committed participation. Patients' motivation is a key determinant of successful rehabilitation outcomes, but it is difficult in defining and measuring. Patients' participation is defined as the degree or extent to which subjects take part in rehabilitation activities and can be measured by observable behavior. Objects: The purpose of this study was to investigate the impact of patients' level of participation in rehabilitation on functional outcomes in patients with stroke. Methods: Forty post-stroke inpatients participated in this study. The level of rehabilitation participation was measured by the Hopkins Rehabilitation Engagement Rating Scale (HRERS). Other measures used for the evaluation were the Rivermead Mobility Index (RMI) and Korean version of the Modified Barthel Index (K-MBI). Overall measurements were made at early intervention and late intervention. Spearman correlation and multiple regression were used to measure the relationships between HRERS, RMI, and K-MBI. Results: The correlation found between HRERS total scores at early intervention and RMI total scores of late intervention was above moderate (r = 0.607, p < 0.01). RMI total scores at early intervention (p < 0.000), HRERS total scores at early intervention (p < 0.001), and disease duration (p < 0.003) were significant predictors of RMI total scores at late intervention. Conclusion: The level of participation at early intervention was associated with improvement in mobility. The level of mobility at early intervention, disease duration, and patients' participation at early intervention were important determinants of functional outcome. These findings suggest that patients' participation should be encouraged in order to achieve successful stroke recovery.

• 융합보안논문지
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• 제19권3호
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• pp.43-50
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• 2019

초연결사회에서 전력기반시설과 정보통신기반시설은 핵심 국가기반시설 중에서도 핵심이다. 그러나 전력기반시설은 최근에 이슈가 되고 있는 북한의 고 고도 핵 전자기파(HEMP) 위협에 매우 치명적이며, 따라서 공격 이후의 빠른 복구를 통한 복원성은 국가의 생존성과 직결되어 있다. 그러므로 전력기반시설은 다른 어떤 핵심기반시설보다 우선하여 선제적인 방호대책과 조기 복구계획이 수립되어야 한다. 본 논문에서는 HEMP 위협의 특성을 살펴보고, 그에 대한 전력기반시설의 위험성 및 효과적인 주요 방호대책을 살펴보았다. 향후 우리나라의 전력기반시설에 대한 '고출력 전자기파 침해 방지' 관련 법·제도의 제·개정 방향을 정립하는데 도움을 줄 수 있을 것으로 기대한다.

• 한국수정란이식학회지
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• 제12권1호
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• pp.57-66
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• 1997

This study was carried out to establish an effective and practical system for commercialization of embryo production techniques by analyzing several factors influencing in vivo embryo production on days and seasons of flushing in Korean native cattle. In vivo embryos were flushed 226 times from 128 donors. The results obtained for the factors influencing in vivo embryo production on days and seasons of flushing were as follows :1.The percentages of fertilized, transferable and freezable embryos by seasons were significantly different in both FSR-P and SUPER-OV(P<0.01). The percentages of them were highest in sunrrner with FS H-P and highest in autumn with SUPER -OV.2. The production of transferable and freezable embryos by flushing days was highest in 8 days with FSH-P, and there was no difference between 7 and 8 days for SUP ER-OV. 3. The failure rates of recovery were 17.0% in SUPER-OV and 21.2% in FSH-P, respectively. The donors superovulated but failed recovery were 8.5% in SUPER-OV and 12.9% in FSH-P, respectively. Nonsuperovulated donors was 8.4% and donors giving less than 2 eggs at recovery was 8.4% in both FSH -P and SUPER-OV 4. The donors returned to normal estrus after superovulation were 34.1% after 1 cycle,39.4% after 2 cycles, and 16.7% after 3 cycles by FSH-P, respectively. For SUPER-OV, they were 55.3, 33.0 and 9.6%, respectively. Generally, normal estrus after the treatment of superovulation was earlier and the occurrence of ovarian cyst was also lower in SUP ER-OV than in FSH-P.5.The percentages of blastocyst in embryos flushed at 7~8 days after estrus were 21. 9% and 54.3% in FSH -P and SUPER-OV, respectively. The development of embryos was faster in SUPER-OV than in FSH-P.(Key words : in vivo embryo, flushing days, superovulation, FSH-P, SUPER-OV)