• Journal of Biosystems Engineering
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• 제21권1호
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• pp.84-93
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• 1996

Several paraffins(CnH2n +2) can be used as the thermal energy storage medium because of their large amount of latent heat and their flexibility of phase change temperature. But they have not been used in the thermal energy storage system because their long term stability have not been verified. Paraffins(CnH2n+2) which the values of n are 23, 24, 26 and 28 were selected for this experimental research. And this research was peformed to apply them to the practical systems. The results were summarized as follows. (1) The increase of phase change cycles had no effect on their phase change temperatures. (2) According as the values of n increased from 23 to 28, the specific heats of paraffins(CnH2n+2) increased, and were in the range of 0.47 0.75 ㎉/$kg^circ C$. (3) Thermal conductivities of them were in the range of 0.14 0.17 W/$m^circ C$. and specific gravities of them were in the range of 765800 kg/m3. (4) The density of paraffins was in the range of 765 800 kg/$m^circ C$ , and the density of solid phase was larger than that of liquid phase. (5) When the number of phase change cycles was 1, 500 cycles, the latent heat of paraffins was 90% of the initial value.

• 한국인터넷방송통신학회논문지
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• 제20권3호
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• pp.189-194
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• 2020

대부분의 사이버 침해사고는 악성코드를 이용한 APT 공격들에 의해 발생하고 있다. 해커들은 공격 대상에 침투하기 위해 이메일 시스템에 메계체로 한다. 내부로 접근하기 위한 방법으로 이메일을 이용하고, 장기간에 걸쳐 수집된 취약점을 이용해 데이터베이스를 파괴하고, 시스템 운영방해 및 랜섬웨어(Ransomware)를 통해서 개인정보를 불법으로 취득하고 있다. 이처럼 이메일시스템은 가장 친근하고 편리하지만 동시에 보안의 사각지대에서 운영되고 있는 게 현실이다. 이로 인해 개인정보 유출사고가 발생한다면 기업 및 사회 전체에 큰 피해를 줄 수 있다. 이번 연구는 기업내에서 운영 중인 이메일 시스템에 대한 보안 구성을 강화하여 APT 공격으로부터 안전하게 관리하기 위한 효과적인 방법론을 제시하고자 하였다.

• KSBB Journal
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• 제19권3호
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• pp.174-177
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• 2004

기내에서의 발아 및 형질전환 활성을 지닐 수 있는 백합 (Lilium longiflorum) 화분의 장기보존조건을 얻기 위하여 용매를 이용한 연구를 수행하였다. 화분의 용이한 수집을 위하여 용매를 사용했을 때, petroleum ether, n-heptane, benzene 등의 경우 화분의 기내발아에는 영향을 미치지는 않았으나 수집과 정 후 바로 화분건조 및 냉동 보관함으로써 발아활성을 유지 할 수 있었다. 이들의 활성유지는 또한 vacuum infiltration 및 Agrobacterium을 이용한 형질전환에 따른 외래유전자인 tissue plasminogen activator의 발현에 의하여 확인하였다.

• 한국콘텐츠학회논문지
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• 제12권7호
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• pp.1-10
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• 2012

오늘날 인터넷과 전자출판 기술은 매우 발달되었고 고품질의 해외 학술정보를 이용하는 것은 매우 많은 이익을 가질 수가 있다. 국내 연구자들은 이런 고품질의 전자저널 원문에 대한 요구가 증대되고 있다. 또한 국가 상호간에 전자저널들을 안전하게 보존 및 서비스하기 위해서는 서로 간에 디지털 아카이빙의 활동이 필요하다. 따라서 본 논문에서는 전자저널 국가컨소시엄 참가기관 이용자들에게는 One-Stop 전자원문 무료 서비스와 중소기업, 개인이용자들에게도 저렴한 전자원문 유료 서비스 제공하며 국가적인 전자정보자원의 장기보존체계를 마련을 하기위한 전자원문 로컬호스팅 시스템을 구현하였다.

• 한국자원식물학회지
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• 제19권6호
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• pp.665-669
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• 2006

Somatic embryos do not survive at exposure to liquid nitrogen temperatures without cryoprotective treatments. A simplified technique which simultaneously induces and cryoprotects embryogenic calli using plant vitrification solution 2 (PVS2) followed by dehydration was developed for the cryopreservation of Soap berry genetic resources. Vitrification is a way of removing the moisture in vegetation through PVS2. The PVS2 vitrification solution consisted of 30% glycerol (w/v), 15% ethylene glycol (w/v), 15% Dimethylsulfoxide (w/v) in B5 medium containing 0.4M sucrose. Two tests were done. The one was to eliminate moisture at $0^{\circ}C$ and the other at $25^{\circ}C$. In both cases the best results came out at a vitrification time of $10{\sim}20$ minutes. It was also found that the survival rate was higher at $0^{\circ}C$ than at $25^{\circ}C$. In particular, the survival rate reached more than 80%. Water-damaged embryos turned brown and stoped growth, but energetic embryos took on a milky hue and show a very vigorous growth rate. Successful cryopreservation of somatic embryos of soapberry can be used to establish in vitro genebanks for long-term conservation of Soapberry genetic resources to complement field genebanks and other in vitro methods already being used.

• 한국실내디자인학회논문집
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• 제23권4호
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• pp.231-239
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• 2014

This study is regarding the accessibility for the disabled in the catholic churches. The purpose is to check the current condition of the accessibility for the disabled and to suggest the improvement plans targeted at 10 churches located in Yuseong-gu, Daejeon metropolitan city. Especially the current condition of the obligations and recommendations specified in the accessibility enhancement law for the disabled was performed through field investigation. Firstly, the accessibility for the disabled of each church was evaluated qualitatively as well as quantitatively. And then sequential improvement plans divided into three stages were suggested. Above all, the parish, management authority of catholic churches should establish medium and long-term plans besides legal standards. Even though the scope of this research was limited to catholic churches of certain areas, the result of this research is expected to help investigation the current condition of the accessibility for the disabled and to suggest the improvement plans in other catholic churches.

• 한국약용작물학회지
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• 제2권1호
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• pp.38-43
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• 1994

미국 일리노이에 자생하는 야생 까마중종인 Solanum ptycanthum과 Solanum nigrum의 어린자옆으로부터 유기된 callus를 2년이상 장기간 계대배양 후 식물체 분화율을 제고하기 위하여 IAA, BA, thidiazuron의 효과를 조사하였다. callus 생장과 식물체분화는 IAA와 BA를 혼합처리시보다 thidiazuron을 단독처리 하였을 때가 4-5배 효과적이었다. Thidiazuron과 IAA와 BA간에는 식물체분화에 상호작용이 있었으며 thidiazuron을 단독처리시보다 IAA를 첨가시 식물체 분화를 감소하였다.

• 정보저장시스템학회논문집
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• 제10권2호
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• pp.32-38
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• 2014

Heat emission from the laser diode used in the optical disc drive and the defects from the increased temperature at the system have attracted attentions from the field of the information storage device. Thermoelectric refrigerator is one of the fine solutions to solve these thermal problems. The refrigeration performance of thermoelectric device is dependent on the thermoelectric material's figure-of-merit. Meanwhile, high electrical contact resistivity between metal electrode and p- and n-type thermoelectric materials in the device would lead increased total electrical resistance resulting in the degeneracy in performance. This paper represents the manufacturing process of the PbTe-based material which has one of the highest figure-of-merit at medium-high-temperature, ~ 600K to 900 K, and the nickel contact layer for reduced electrical contact resistance at once, and the results showing the decent contact structure and figure-of-merit even after the long-term operation environment.

• East Asian Economic Review
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• 제21권4호
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• pp.343-384
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• 2017

We assess the outcomes for the negotiating parties in the Trans-Pacific Partnership if the remaining eleven parties go ahead with the agreement as negotiated without the United States, as compared to the outcomes under the original twelve-member agreement signed in October 2016. We find that the eleven-party agreement, now renamed as the Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP), is a much smaller deal than the twelve-party one, but that some parties do better without the United States in the deal, in particular those in the Western Hemisphere - Canada, Mexico, Chile, and Peru. For the politically relevant medium term, the United States stands to be less well-off outside the TPP than inside. Since provisional deals can be in place for a long time, the results of this study suggest that the eleven parties are better off to implement the CPTPP, leaving aside the controversial governance elements, the implications of which for national interests are unclear and which, in any event, may be substantially affected by parallel bilateral negotiations between individual CPTPP parties and the United States.

• Journal of Microbiology and Biotechnology
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• 제11권6호
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• pp.922-927
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• 2001

In an effort to regulate the mammalian cell behavior in entrapment with a gel, we have functionalized hydrogels with the putative cell-binding (-Arg-Gly-Asp-)(RGD) domain. An adhesion molecule of Gly-Arg-Gly-Asp-Ser (GRGDS) peptides, a cell recognition ligand, was induced into thermo-reversible hydrogels, composed of N-isopropylacrylamide with small amounts of acrylic acid (typically 2-5 $mol\%$ in feed), as a biomimetic extracellular matrix (ECM). The GRGDS containing a p(NiPAAm-co-AAc) copolymer gel was studied in vitro for its ability to promote the spreading and viability of cells by introducing a GRGDS sequence. Hydrogel with no adhesion molecule was a poor ECM for adhesion, permiting spreading of only $3\%$ of the seeded cells for 36h. By immobilizing the peptide linkage into the hydrogel, the conjugation of RGD promoted $50\%$ of proliferation for 36h. However, the GREDS sequence, nonadhesive peptide linkage, conjugated hydrogel showed only $5\%$ of the seeded cell for the same time period. In addition, with the serum-free medium, only GRGDS peptides conjugated to hydrogel was able to promotecell spreading, while there was no cell proliferation in the hydrogel without GRGDS. Thus, the GRGDS peptide-conjugated thermo-reversible hydrogel specifically mediated the cell spreading. This result suggests that utilization of peptide sequences conjugating with the cell-adhesive motifs can enhance the degree of cell surface interaction and influence the long-term formation of ECM in vitro.