• Title/Summary/Keyword: 안정화 가능성

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Utilization of Electric Arc furnace Slag md Converter Slag after Aging for Concrete Aggregate (콘크리트용 골재로서 에이징처리한 제강슬래그외 활용)

  • 문한영;유정훈
    • Journal of the Korea Concrete Institute
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    • v.14 no.4
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    • pp.597-607
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    • 2002
  • Electric arc furnace and converter slag are produced by about 6 millions tons in Korea at 2000 year. But compared with blast furnace slag, those are utilized only in unvalued material like landfill and road construction. There are unstable materials, like free CaO, in electric arc furnace and converter slag at steel-manufacturing process. This might cause volume expansion in concrete, if electric arc furnace and converter slag aggregates were used in concrete. This expansion may reach to crack or collapse of concrete. It is therefore settled by standard specification for concrete that electric arc furnace and converter slag aggregates have not to use in concrete. First of all, volume stability and stabilized process should be solved in electric arc furnace and converter slag aggregate to use in concrete. In this study, 6 types of aging are evaluated for effects of stabilization to reduce the expansion of electric arc furnace and converter slag. h converter slag aggregate, these types of aging are not good for volume stability for concrete aggregate, and even if converter slag aggregate is treated with aging, concrete with it has some problems that strength is reduced with curing days. But in electric arc furnace slag aggregate treated with hotwater and steam aging, the expansion of electric arc furnace slag aggregate is reduced about two times than that of converter slag aggregate, and electric arc furnace slag aggregate concrete has good results in strength compared with control concrete using crushed stone.

Stabilization of Quercetin using Organo-hectorite and Its Application in Sunscreen Cosmetics (오가노 헥토라이트를 이용한 쿼세틴 안정화 및 자외선 차단 제품 응용에 관한 연구)

  • Sang Uk Kim;Ji Yeon Hong;Yong Woo Kim;In Ki Hong;Song Hua Xuan;Mid Eum Yun;Sung Ho Lee
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.50 no.1
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    • pp.1-10
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    • 2024
  • In this study, a quercetin benton gel (QUERPLEX) that stabilized quercetin was prepared using organo hectorite, and its efficacy was confirmed. In addition, a comparative study was conducted on the stability and effectiveness of applying this to sunscreen cosmetics. It was confirmed that QUERPLEX remained stable without showing crystal precipitation and growth for 4 weeks. As a result of measuring antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH), it showed antioxidant activity depending on the concentration, and showed a radical elimination ability of 70% or more at a concentration of 2,500 ppm or more, confirming a significant effect. Anti-inflammatory activity experiments using RAW 264.7 cells confirmed that NO production decreased in a concentration-dependent manner by reducing NO production by 8% at 25 ㎍/mL, 23% at 50 ㎍/mL, and 84% at 100 ㎍/mL. As a result of confirming the stability of the formulation according to the method of quercetin in the sunscreen formulation, the stability of the formulation was improved when quercetin was added directly to the formulation. It also improved the UV protection index on in vitro and in vivo, which is expected to have the potential as a component that can have a new boosting effect on UV protection. These results suggest that organo hectorite is very effective as a quercetin carrier and that it can be applied in cosmetic formulations by not only expressing the efficacy of quercetin but also bringing about additional effects.

Evolution of Medicinal Crop Industry as the Bio-resources in the 21st Century (21세기 생물산업 소재인 약초 산업의 진화)

  • Park, Chun-Geon;Kang, Yong-Ku;Choi, Ae-Jin;Lee, Jeong-Hoon;Woo, Jong-Gyu;Park, Chung-Berm
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2011.10a
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    • pp.8-8
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    • 2011
  • 인류는 자연으로부터 식량과 질병 치료를 위하여 자연스럽게 약초를 얻을 수 있었다. 약 6만 년 전 네안데르탈인의 무덤에서 오늘날 향료로 쓰이는 약초가 발견 될 정도로 인류가 약초를 이용한 역사는 오래 되었다. 약초는 난치병, 노화, 성인병 등 현대의학에서 미비점을 보완하는 대체의약 산업의 원료이자 새로운 생물자원의 보고로서, 그 중요성이 커지고 있다. 새로운 생물자원 소재로 약초는 약용성분을 함유한 식물자원의 확보 및 개발 등 고부가산업의 소재로 선진국에서 연구개발의 경쟁이 치열하며, 약초산업은 천연소재 신약과 기능성 식품, 화장품, 생활용품 등으로 확대되고 있다. 의약품 분야에서는 새로운 시대의 중요한 생명산업으로서 약초는 한약뿐 아니라 신약 개발을 위한 소재로도 부각되고 있으며, 항암제인 택솔, 신종플루 치료제인 타미플루 등 천연물 약의 가능성은 이미 증명되었다. 식품 분야에서는 재배기술 발달과 웰빙 트렌드 속에서 약초는 신선채소와 기능성 식품으로 변신하고 있다. 한약재의 이미지를 벗어난 약초는 음료와 과자, 술 등으로 활용되고, 비빔밥 등 다양한 약선음식으로도 개발되고 있다. 산업소재의 활용분야에서는 약초는 특히 화장품 산업의 소재로 각광받고 있다. 이미 다양한 화장품 회사에서 한방화장품을 출시하여 세계 속으로 진출하고 있다. 또한 약초는 천연 색소이자 생활 용품의 소재로 활용되고 있는데, 약초를 활용한 염색약과 여성 생리대, 샴푸 등의 인기가 높다. 약초산업의 부가가치 증대를 위하여 한약재 위주의 약초산업을 천연물 신약, 기능성 식품, 화장품, 산업 소재 등 고부가가치 시장으로 확장시키고, 우리 약초 산업의 세계화를 추진해야 한다. 연구개발 투자 확대와 빠르게 변화하는 시장을 반영하여 연구 방향을 수립하고, 산학연 및 생산자단체 등과 새로운 약초 산업의 블루오션 창출을 위해 협력을 해야 할 것이다. 또한 약초의 생산기술 안정화를 통해 산업화 기반을 구축하여, 약초 공급의 안정화, 약초 생산 농가 소득 안정화가 필요하며, 마지막으로 변해가는 약초 산업의 트렌드에 부응할 수 있는 품질관리와 유통 질서 확립을 위한 정책과 제도의 선진화가 뒷받침 되어야 할 것이다.

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Physicochemical Stabilities of Carthamins from Safflower Petals as Food Colorants (홍화 Carthamin의 식품색소로서의 안정성)

  • Yoon, Joo-Mi;Hahn, Tae-Ryong;Yoon, Hye-Hyun
    • Korean Journal of Food Science and Technology
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    • v.33 no.6
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    • pp.664-668
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    • 2001
  • The physical and chemical stabilities of carthamin of red pigment from safflower petals were investigated at various conditions of pHs, temperatures, inorganic ions, sugars, light and polysaccharides. The half-life values at pH 3.0, 5.0, 9.0 and 11.0 were 5.3, 5.0, 11.0 and 45.0 h, respectively, at $25^{\circ}C$. Therefore, carthamin is unstable at acidic condition. Carthamin was red, orange and yellow at acidic, neutral and alkaline solutions, respectively. At pH 3.0, carthamin was thermally unstable and the half lives were 3.62, 9.05 and 48.2min at $90^{\circ}C$, $70^{\circ}C$ and $50^{\circ}C$, respectively. Among various inorganic ions, $Al^{3+}$ stabilized carthamin at acidic condition. At pH 5.0, carboxymethylcellulose prolonged the half-lives of carthamin at $25{\sim}90^{\circ}C$. Carthamin was very sensitive to light (20,000 lux) and the half-life was 2.32 min at pH 3.0.

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A Study on the User-contributed Reviews for the Next Generation Library Catalogs (차세대 도서관 목록의 이용자 서평에 관한 고찰)

  • Yoon, Cheong-Ok
    • Journal of the Korean Society for Library and Information Science
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    • v.46 no.2
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    • pp.115-132
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    • 2012
  • The purpose of this study is to examine the current status of user-contributed reviews for the Next Generation Library Catalogs, and the potential impact of user reviews available from the external sources, including Amazon.com and GoodReads.com. During the period of February 16th through April 4th, 2012, the number of holding libraries and user-contributed reviews, tags and reading lists of ten selected books were examined from the WorldCat. Also the user-contributed reviews for the same books available from Amazon.com and GoodReads.com were examined, and a case of reviews for one book was analyzed. The result shows that only a few users participated in the WorldCat, and user-contributed reviews were rarely used, when compared with tags or reading lists. Several hundred to thousand user-contributed reviews for the same books were available from Amazon.com and GoodReads.com directly linked with bibliographic records. A case of one book from Amazon.com reveals the possibility of distorting the function of user-contribution. With the introduction of the function of user-contribution, it is expected that its growth rate should be carefully observed and its potential impact on users should be thoroughly and systematically analyzed in the near future.

Comparative study on the O/D estimation using Gradient method and Generalized Least Square method (Gradient방법과 일반화최소자승법을 이용한 관측교통량기반 O/D 추정방법에 관한 예측력 비교평가 연구)

  • 이승재;김종형
    • Journal of Korean Society of Transportation
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    • v.18 no.2
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    • pp.41-52
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    • 2000
  • In the developing country, the transportation situation is changed very quickly and the transportation environment is not stable. So the transportation planning should be frequently made in considering the limited cost and time. And the traditional large-scale survey(household survey, roadside interview, etc.) has many Problem like the difficulty for doing it and getting mood results. Therefore the study about the method of evaluation on the traffic count based O/D matrix is Processing actively recently. Though the many study for the network in the realistic size are enacted, the study for comparing with the advantage and disadvantage of each method are few. Therefore this study mainly deals with the static method among the existing models of evaluation on the traffic count based O/D matrix(in terms of the transportation plan). Bi-level(GU) and gradient method are selected as main alternative model and analyzed their capability and validity. For testing the reliability of the models, Bi-level(GLS) and gradient method are adapted to toy network. Then we analyze the result of testing, and study the way for large network.

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Local Separation Principle of Fuzzy Observer-Controller (퍼지 관측기-제어기의 국소적 독립 원리)

  • Lee, Ho-Jae;Park, Jin-Bae;Joo, Young-Hoon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.14 no.7
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    • pp.902-906
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    • 2004
  • A separation principle of the Takagj-Sugeno (T-S) fuzzy-model-based observer-control is investigated. When the premise variables are able to be measured or directly computed from the outputs of the T-S fuzzy system and the fuzzy inference rules for the plant, control, and observer share the premise parts, the T-S fuzzy-model-based observer and the T-S fuzzy-model-based control can be separately designed such that the global stabilizability is guaranteed by the fuzzy observer-based output-feedback control. In this case, the global separation principle is well established. On the other hand, when the premise variables are unmeasurable or cannot be computed from the outputs, they should also be estimated. We examine the separation principle of this case. If the decay rates of the T-S fuzzy-model-based control and observer are sufficiently fast, the global separation is assured. Otherwise we show that the separation principle holds locally.

Analysis of Per-Position Characteristics Recognized by Tenure Women Managers (근속 여성관리자가 인식하는 직위별 특성 분석)

  • Jeong, Ji-ae
    • Journal of Practical Engineering Education
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    • v.11 no.1
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    • pp.105-115
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    • 2019
  • This study focused on the importance of job position as a role model for female career adaptation. To do this, we used the KWMP data to conduct a Multinomial logit analysis to examine the influence factors of the tenure women managers. As a result, first, section chief position showed a low level of life satisfaction and showed difficulty of beginner's manager. Second, it is predicted that the position of the Deputy Head of Department will establish the identity of work as an intermediate manager. Third, head of department Director showed a high age, target status, possibility of achieving the target, and duration of the next job. Fourth, executive level has the least average experience of discrimination on monthly average wage. It was suggested that it is important to develop individual career by recognizing that the organizational atmosphere and personnel management are lower than those of the other positions. It was found that age, organizational atmosphere and personnel management, goal status, possibility of achieving goals, next job tenure period, monthly average wage, welfare, and life satisfaction factors were the most influential factors in women career adjustment. Finally, implications and limitations were discussed based on the results of this study.

신주공모발행(新株公募發行)에서의 인수기관선정(引受機關選定) 및 인수조건(引受條件) 선정방식(選定方式)에 관한 실증연구(實證硏究) - 미국의 공익기업(公益企業)을 대상으로 -

  • Yeon, Kang-Heum
    • The Korean Journal of Financial Management
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    • v.14 no.1
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    • pp.219-247
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    • 1997
  • 우리나라에서는 그 동안 유상증자(有償增資)시 주주배정(株主配定)(right offer)방식에 의하고 기업공개시의 발행가격도 일률적으로 산정(算定)되어 증권인수(證券引受)에 따른 인수기관(引受機關)(underwriter)의 역할이 제한되어 왔으나 앞으로는 증권발행방식이 다양화되어 발행가격의 결정을 포함한 인수기관의 역할이 강조될 것이다. 대부분 총액인수(總額引受)(firm commitment underwriting)방식을 택하는 미국자본시장에서 인수기관을 선정하고 발행조건들을 결정하는 방법에는 투자은행과의 협의(協議)(negotiation)에 의하는 방식과 비공개경쟁입찰(非公開競爭入札)(sealed bidding)에 의하는 방식이 있는데 많은 기업들은 상대적으로 비용이 많이 드는 협의발행을 선택한다. 본 연구에서는 이에 대한 가설들을 뉴욕증권거래소나 아메리칸증권거래소에서 거래되는 공익기업의 신주발행자료를 통해 실증 검정했다. 인수 스프레드(underwriting spread)는 발행금액에 관계없이 협의발행(協議發行)이 경쟁발행(競爭發行)보다 평균적으로 1.16% 높았으며 발행비용(發行費用)도 협의발행이 유의적인 수준에서 0.341% 정도 높았다. 비대칭정보하에서 신호균형(信號均衡)(signaling equilibrium)으로 설명할 수 없지만 협의발행에 의한 통합균형(統合均衡)(pooling equilibrium)의 가능성은 배제하지 못했다. 주식발행 발표일(發表日)(announcement date)을 전후해 인수방식에 따른 주가변동의 차이를 분석한 결과 대리인가설(代理人假說)은 부분적으로 지지했다. 발행일(發行日)(offering date)을 전후한 주가변동에 의하면 인수기관의 사전매각노력(事前賣却努力)이 협의발행하에서 더 높았으나 발행일 직후의 주가회복은 보이지 않아 인수방식에 따른 가격안정화(價格安定化) 노력의 차이는 없었다. 발행기업들간의 주가차별화의 정도를 분석한 결과 협의발행에서 인회활동(認淮活動) (certification effects)을 더 잘 할 수 있다는 사실을 지지하지 못했다.

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A Study on the Multi-Modal Browsing System by Integration of Browsers Using lava RMI (자바 RMI를 이용한 브라우저 통합에 의한 멀티-모달 브라우징 시스템에 관한 연구)

  • Jang Joonsik;Yoon Jaeseog;Kim Gukboh
    • Journal of Internet Computing and Services
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    • v.6 no.1
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    • pp.95-103
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    • 2005
  • Recently researches about multi-modal system has been studied widely and actively, Such multi-modal systems are enable to increase possibility of HCI(Human-computer Interaction) realization, enable to provide information in various ways and also enable to be applicable in e-business application, If ideal multi-modal system can be realized in future, eventually user can maximize interactive usability between information instrument and men in hands-free and eyes-free, In this paper, a new multi-modal browsing system using Java RMI as communication interface, which integrated by HTML browser and voice browser is suggested and also English-English dictionary search application system is implemented as example.

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