• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집A
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• pp.67-76
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• 2000

Cr-Mo low alloy steels have been used for a long time for pressure vessel due to its excellent corrosion resistance, high temperature strength and toughness. The paper reviewed the latest trends on material development and some problems on Cr-Mo low alloy steel for pressure vessel, such as elevated temperature strength, hardenability, synergetic effect between temper and hydrogen embrittlement, hydrogen attack and hydrogen induced disbonding of overlay weld-cladding.

• Journal of Ginseng Research
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• 제19권1호
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• pp.22-26
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• 1995

The present study was undertaken to elucidate the characteristics of red ginseng total saponin in behavioral changes on ambulation, forced swim test and convulsion in mice. The ambulation and the duration of immobility on forced swim test were not affected by red ginseng total saponin. On the other hand, the duration of immobility inducted by DMI, PGL but not CIP was significantly decreased, and the onset of convulsion induced by pentylenetetrazole was significantly shortened by preadministration of red ginseng total saponin. These results suggest that red ginseng total saponin component may play an important role in modulating synergism with drugs acting on depression and convulsion, and that the characteristics of synergetic effect induced by red ginseng total saponin potentate the central norepinephrine neuron activity.

• 정보기술과데이타베이스저널
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• 제7권1호
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• pp.1-15
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• 2000

A repository has been conceived as a critical weapon for managing organizational information resources. The system can help control the heterogeneous data in a variety of CASE (Computer-Aided Software Engineering) tools. However, current repository systems have limitation in creating a synergetic effect by integrating information resources. Therefore, it is important to develop an integrative repository system, called Enterprise Repository System (ERS). This paper (i) defines ERS on the basis of a framework for repository systems, and (ii) suggests an ERS architecture and its detailed components. Finally, a real-life case of developing ERP repository system is illustrated according to the proposed architecture and components. This illustration may demonstrate the usefulness of this research for help developing an advanced repository system.

• International Journal of Computer Science & Network Security
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• 제21권12spc호
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• pp.477-482
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• 2021

The existing approaches to ensuring the banking security of the state do not take into account the peculiarities of the banking system in the rapid development of the information economy (increasing uncertainty, imbalance and nonlinearity of processes in the banking system under the influence of innovation, institutions, information asymmetry, etc.). A methodological approach to determining the synergetic effect in the implementation of the regulatory influence of the state on the development of innovation processes related to informatization in the banking system, based on the use of differential equations and modelling the sensitivity of innovation processes related to informatization in the banking system, to the regulatory influence of the state to prevent the deployment of risks and threats to economic security of the state in this area has been suggested in the present article.

• Animal Bioscience
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• 제36권9호
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• pp.1305-1313
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• 2023

Synthetic antioxidants have shown adverse effects on consumers. The review, thus, aims to assess the effect of marinating broiler meat with plant leaves-derived antioxidants potential for improving shelf-life and human health. Broiler meat loss and waste due to spoilage is more than three million kg annually, thus, extending shelf-life by reducing initial microbial load and autoxidation is essential. Adding various antioxidants would reduce oxidation of protein and fatty acids improving nutritional shelf-life through synergic interactions. Antioxidant synergetic effects also improves reduction in microbiota proliferation leading to the delayed development of off flavours and deterioration of meat colour. To reduce initial microbial load and autoxidation effects, the inclusion of polyphenols and antioxidants from varying sources by mixing various antioxidants would lead to improved synergic effects.

• 한국응용과학기술학회지
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• 제34권2호
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• pp.349-356
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• 2017

본 연구에서는 $TiO_2$ nanotube 광촉매의 고도산화처리능을 비교하기 위해서 OH 라디칼 생성력을 평가하고자 하였다. 자외선 조사에 따른 Probe compound인 4-Chlorobenzoic acid (pCBA)의 농도 감소에 따라 OH radical 생성량을 산정하는 방법으로 광촉매 효율을 평가하였는데, $TiO_2$ nanotube 표면에서의 전자의 흐름을 원활하게 하기 위하여 전기적 에너지를 주었을 시 광촉매 효율의 증가 가능성 또한 확인하고자 자외선 조사 시 전류밀도를 인가하는 방법으로 실험을 진행하였다. 실험에 사용된 $TiO_2$ nanotube는 전극효과를 부여하기 위해 양극산화법으로 티타늄판을 이용하여 제조하였으며, pCBA 용액에는 전도도를 부여하기 위하여 NaCl을 첨가하여 전해질로 사용하였다. 정전류 정전압 조건하에서 자외선조사 실험을 진행하였으며, 전류가 흐르는 광촉매에 자외선 조사 시 OH 라디칼 생성량은 광촉매 없이 자외선만 조사하였을 때에 비해 약 5.6배, $TiO_2$ 광촉매와 함께 자외선을 조사하였을 보다 약 2.2배 증가하였다. 결과적으로 광촉매반응에 전기적 에너지를 부여하였을 시 시너지효과를 가져올 수 있는 가능성을 확인할 수 있었다.

• 한국가금학회지
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• 제16권4호
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• pp.219-232
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• 1989

본 연구는 닭에 있어서 사료성분에 대한 췌장소화효소(amylase. trypsinogen 및 chymotrypsinogen) 분비기구에 대해서 검토했다. 먼저, 췌효소분비의 단기응답실험에 유용한 새로운 췌액채취법을 개발했다. 이 방법을 이용해서 아미노산 및 glucose를 날개정맥으로 투여한 결과 phenylalanine만이 trypsinogen 및 Chymotrypsinogen이 증가되었지만 그 외의 아미노산 및 glucose에 의해서는 분비증가 효과가 없었다. Cholecystokinin(CCK)투여 에 의해 췌효소분필는 즉각적으로 높은 분비반응을 보였으며, 이 반응은 또한 농도의존성을 나타냈다. CCK투여는 chymotrypsinogen의 쪽이 amylase 및 trypsinogen보다 높은 비율로 분비되는 선택적인 분비반응을 나타냈다. 아미노산과 CCK을 공동투여하면 첨가한 아미노산의 종류에 따라 췌효소분비반응은 여러 가지 형태로 증가되었지만 glucose와의 공동투여에서는 CCK 단독투여와 비교해서 차가 없었다. Valine과 arginine을 여러 가지 농도로 CCK와 공동 투여한 결과, valnine에서는 0.5mM일때, arginin에서는 5mM일때 가장 높은 분비반응을 보였다. 위의 결과로부터 아미노산의 조합에 의한 췌효소분비반응에 대해서 검토했다. 즉, 아미노산 mixture, threonine＋phenylalanine＋isoleucine, Threonine＋phenylalanine, threonine＋isoleucine 및 phenylalanine＋isoleucine과 CCK를 공동투여 했다. 각 물질을 투여한 후 50분간 분비한 효소를 비교하면, threonine＋phenylalanine에 의한 췌효소분비반응은 아미노산 mixture에 의한 분비반응과 동일하게 높은 반응을 보였다. 이상의 결과로부터 닭에 있어서 췌장소화효소분비는 CCK와 아미노산의 사이에 협동작용이 있으며, 그 협동작용은 아미노산의 종류에 따라 선택적인 분비반응을 함으로써 장내소화가 진행된다고 본다.

• 한국자동차공학회논문집
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• 제12권5호
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• pp.40-57
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• 2004

The effects of triple (pilot, main and after) injection on combustion and emission characteristics in a HSDI (High-Speed Direct Injection) diesel engine were investigated using a single-cylinder optical diesel engine equipped with a common-rail injection system. The pilot injection affected the spray and combustion evolution of the following main injection. It was found that the pilot injection reduced the ignition delay, which led to lowered NOx (Nitric Oxides) level, and increased IMEP (Indicated Mean Effective Pressure) due to slow combustion pace during an expansion stroke. The after-injection was shown to be effective in reducing PM (Particulate Matter) even when a small amount of fuel was added. The results suggest that a proper combination of individual injection strategy could bring about a good synergetic effect on engine performance and emission.

• Bulletin of the Korean Chemical Society
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• 제32권10호
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• pp.3660-3665
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• 2011

CO-tolerant PtMo/C alloy electrocatalyst was prepared by a colloidal method, and its electrocatalytic activity toward CO oxidation was investigated. Electrochemical study revealed that the alloy catalyst significantly enhanced catalytic activity toward the electro-oxidation of CO compared to Pt/C counterpart. Cyclic voltammetry suggested that Mo plays an important role in promoting CO electro-oxidation by facilitating the formation of active oxygen species. The effect of Mo on the electronic structure of Pt was investigated using X-ray absorption spectroscopy to elucidate the synergetic effect of alloying. Our in-depth spectroscopic analysis revealed that CO is less strongly adsorbed on PtMo/C catalyst than on Pt/C catalyst due to the modulation of the electronic structure of Pt d-band. Our investigation shows that the enhanced CO electrooxidation in PtMo alloy electrocatalyst is originated from two factors; one comes from the facile formation of active oxygen species, and the other from the weak interaction between Pt and CO.

• Elastomers and Composites
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• 제58권2호
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• pp.70-80
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• 2023

The effect of phenylphosphonic acid (PPOA) on polyurethane (PU) thermal stability was studied through Fourier transform infrared spectroscopy and Thermogravimetric analysis. To synthesize PPOA-modified PUs (PPOA-PUs), polyether-type diols (Mw=62, 106, 190, 419, 605) were chemically modified with PPOA and then reacted with 4,4'-dicyclohexylmethane diisocyanate (H₁₂MDI) and 4,4-diphenylmethane diisocyanate (MDI). During thermal decomposition in air, the PPOA embedded in the PUs formed intumescent phosphocarbonaceous char. Below 400℃, PPOA-H₁₂MDI-PUs were more unstable, as PPOA decomposed at lower temperatures than phenyl groups and aliphatic ethers. Above 550℃, the thermal stability of PUs followed this order: PPOA-MDI-PUs > PPOA-H₁₂MDI-PUs > MDI-PUs > H₁₂MDI-PUs. At 700℃, unmodified PUs had no residue, while the PPOA-MDI-PU residue was 4.4~23.0 wt.% and the PPOA-H₁₂MDI-PU residue was 1.5~17.5 wt.%. The enhanced thermal stability of PPOA-MDI-PUs at high temperatures can be attributed to the synergetic effect of PPOA and phenyl groups on the formation of phosphocarbonaceous char.