• Title/Summary/Keyword: 촉진효과

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An Experimental Study on the Effect of Reduced Slag and Gypsum on Concrete at Low Temperature(-5℃) (저온(-5℃)에서의 환원슬래그 및 석고가 콘크리트에 미치는 영향에 관한 실험적 연구)

  • Kim, Hyeong-Cheol;Choi, Hyun-Kuk;Min, Tae-Beom;An, Dong-Hee;Choi, Si-Hyun;Lee, Han-Seung
    • Journal of the Korea Institute of Building Construction
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    • v.17 no.3
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    • pp.279-285
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    • 2017
  • In this study, the development of concrete preventing initial frost damage and durability about that were evaluated by using anti-aging agent and admixture(reduced slag). As a result of experiment, initial hydration heat was increased by $C_{12}A_7$ of reduced slag components but it was not effective to development of strength. Also fluidity decreased with increasing replacement of reduced slag. This suggested that fluidity was low by rapid setting due to absent of gypsum in reduced slag components. In case of CR2G specimen that added 4% gypsum, the flow ability was higher than plain. It is considered that concrete developed using reduced slag should use $SO_3$. Result of durability experiments, the durability decreased with increasing replacement amount of reduced slag.

Protective Effect of Glycoprotein Isolated from Cudrania tricuspidata on Liver in $CCl_4$-treated A/J Mice (생쥐에 있어서 꾸지뽕 당단백질의 간보호 효과)

  • Joo, Heon-Yeong;Lim, Kye-Taek
    • Korean Journal of Food Science and Technology
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    • v.41 no.1
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    • pp.93-99
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    • 2009
  • This study aimed to determine whether or not glycoprotein isolated from Cudrania tricuspidata Bureau fruit(CTB glycoprotein) exerts a hepatoprotective effect on liver injury induced by the administration of carbon tetrachloride($CCl_4$, 1.0mL/kg) to A/J mice. Following the administration of CTB glycoprotein(0-20mg/kg), the activities of antioxidant enzymes (superoxide dismutase(SOD), catalase(CAT), and glutathione peroxidase(GPx)), and the quantities of measured thiobarbituric acid reactive substances(TBARS), lactate dehydrogenase(LDH), and nitric oxide(NO) were evaluated from the murine liver tissues and plasma. Additionally, the activity of nuclear factor-kappa B(NF-${\kappa}B$) was assessed after pretreatment with $CCl_4$. When the mice were treated with $CCl_4$ alone, the activities of antioxidative enzymes reduced but amounts of TBARS, LDH, and NO increased. However, the results of treatment with CTB glycoprotein(10 and 20 mg/kg) revealed significantly increased activities of antioxidant enzymes(SOD, CAT, and GPx), as compared with $CCl_4$ alone. On the other hand, the result showed significant diminutions of the quantities of TBARS, LDH, and NO after treatment with CTB glycoprotein(10 and 20 mg/kg), as compared to $CCl_4$ alone. The activity of NF-${\kappa}B$ also declined after pretreatment with CTB glycoprotein, as compared with $CCl_4$ treatment alone. Thus, it is suggested that the CTB glycoprotein exerts a protective effect against $CCl_4$-induced liver injury in A/J mice.

Effects of Unripe Black Raspberry Water Extract on Lipid Metabolism and Oxidative Stress in Mice (복분자 미숙과 물 추출물이 마우스의 지질대사 및 산화적 스트레스에 미치는 영향)

  • Choi, Hye Ran;Lee, Jung-Hyun;Lee, Su Jung;Lee, Min Jung;Jeong, Jong Tae;Lee, Tae-Bum
    • Korean Journal of Food Science and Technology
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    • v.46 no.4
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    • pp.489-497
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    • 2014
  • We examined the effects of unripe black raspberry water extract (UBR-W) on lipid metabolism and oxidative stress in mice. C57BL/6J mice were divided into 4 groups: those administered a control diet (CTL), high-fat diet (HFD), UBR-W and simvastatin for 12 weeks. In the HFD group, LDL cholesterol were significantly higher than in the CTL group. However, the UBR-W treated group showed dose-dependent reduction of plasma LDL levels. Hepatic total lipid, TC, and malondialdehyde were significantly increased in hyperlipidemic mice. However, supplementation with either UBR-W or simvastatin effectively reduced these lipid profiles and lipid peroxidation. UBR-W increased mRNA expression of the LDL receptor, sterol regulatory element binding protein 2 (SREBP2), 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase and ATP-binding cassette transporter A1 (ABCA1) compared to that observed in the HFD group. In addition, UBR-W and simvastatin showed significantly reduced oxidized LDL uptake by the scavenger receptor CD36. These results suggest that UBR-W is useful for treatment and prevention of hyperlipidemia and lipid peroxidation.

Preparation and Quality Characteristics of Yogurt Added with Saururus chinensis (Lour.) Bail (삼백초를 첨가한 요구르트의 제조와 품질 특성)

  • Lee, In-Seon;Lee, Syng-Ook;Kim, Hyun-Soo
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.3
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    • pp.411-416
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    • 2002
  • Yogurt base was prepared from whole milk and skim milk added with 0.2∼1.0% (w/v) of Saururus chinensis(Lour.) Bail water extract (SCe) and fermented with lactic acid bacterias (the mixed strain of Streptococcas themophilus and Lactobacillus bulgaricus) at 37$\^{C}$ for 24 hr. Quality characteristics of the yogurt were evaluated in terms of acid production, number of viable cells, viscosity and sensory property during lactic acid fermentation. The composition of organic acids was also measured by HPLC. Addition of SCe stimulated the growth of lactic acid bacteria and remarkably enhanced the acid production. The viscosity and lactic acid content of yogurt were also increased by addition of SCe. The sensory score of yogurt added with 0.4% of SCe was significantly higher than other groups in taste and overall acceptability The storage abilities of yogurts added with SCe were relatively good at 5$\^{C}$ for 15 days.

The Study on the Network Targeting Using the Non-financial Value of Customer (고객의 비재무적 가치를 이용한 네트워크 타겟팅에 관한 연구)

  • Kim, Jin;Oh, Yoon-Jo;Park, Joo-Seok;Kim, Kyung-Hee;Lee, Jung-Hyun
    • Journal of Intelligence and Information Systems
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    • v.16 no.2
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    • pp.109-128
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    • 2010
  • The purpose of our research is to figure out the 'non-financial value' of consumers applying networks amongst consumer groups, the data-based marketing strategy to the analysis and delve into the ways for enhancing effectives in marketing activities by adapting the value to the marketing. To verify the authenticity of the points, we did the empirical test on the consumer group using 'the Essence Cosmetics Products' of high involvement that is deeply affected by consumer perceptions and the word-of-mouth activities. 1) The empirical analysis reveals the following features. First, the segmented market for 'Essence Consumer' is composed of several independent networks, each network shows to have the consumers that is high degree centrality and closeness centrality. Second, the result proves the authenticity of the non-financial value for boosting corporate profits by the high degree centrality and closeness centrality consumer's word-of-mouth activities. Lastly, we verify that there lies a difference in the network structure of 'Essence Cosmetics Market'per each product origin(domestic, foreign) and demographic characteristics. It does, therefore, indicate the need to consider the features applying mutually complementary for the network targeting.

Urban Parks and Their Economic Roles - In the Context of Urban Redevelopment, United States - (도시 공원의 경제적 역할 - 미국 도시 재생 운동에서의 사례를 바탕으로 -)

  • Yoon, Heeyeun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.41 no.4
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    • pp.85-101
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    • 2013
  • The primary goal of this research is to link two currently disconnected literature; the history of urban redevelopment and the one of urban parks and open spaces in the United States (US). Through this exercise, this study attempts to reveal examples of urban parks and open spaces that have yielded economic effects, and emphasize their possibility as a measure of urban redevelopment. Five phases are presented, starting with two Pre-World War II urbanization periods, and three subsequent periods of Post-World War II urban redevelopment (1940s~1960s, late 1960s~1970s, 1980s~present). While urban parks in the 19th century urbanization period held a preeminent place in urban design, policy and economy, ensuing depression and World War II diminished their role as a channel to ease unemployment. In the first phase of urban redevelopment, the economic motive to build open space was to boost the appeal of specific locales in order to draw people and businesses back to a neglected city. In the second phase, public effort to create and maintain urban parks and open spaces declined due to the budget austerity, instead, community open spaces flourished through the voluntary actions and helped neighborhoods to regain desirability. In the third phase, the aspirations and functions of such projects resemble their forerunners of the first phase, but their targets extended to global businesses and elites.

용융탄산염형 연료전지 분리판 재료의 부식거동

  • 이충곤
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 1998.05a
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    • pp.21-21
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    • 1998
  • 새로운 에너지원으로 각광받고 있는 연료전지는 우주선 동력윈으로서의 이용이래, 보다 실용적인 발전 시스템을 목적으로 많은 연구개발이 시도되고 있다. 이러한 연료전지는 사용하는 전해질의 특성으로 인하여 저온형($<300^{\circ}C$) 과 고온형($500^{\circ}C<$)으로 구분된 수 있는데, 저온형 연료전지의 경우는 전극반응 특성상 귀금속 촉매가 필요한 데 비해, 고온형 연료전지는 이러한 귀금속 촉매가 필요없다는 점등에서 다양한 장점을 가지게 된다. 즉, 저온형에 비해 다양한 연료가 가능하고, 대형화에 유리함며, 고온 페열을 이용할 수 있는 점 등을 들 수 있다. 용융탄산염형 연료전지(MFCFC)는 이러한 고온형 연료진지의 장점을 배경으로 현재 대규모의 개발이 진행되고 있다. 그러나 여기에 주로 사용되는 Li-K, Li-Na와 같은 용융탄신엽은 고부식성 전해질로서 대부분의 금속이 산화물을 형성하는 것으로 알려져 있다. MCFC의 분리판은 셀간을 전기적으로 이어주는 역할, 가스의 유로제공 및 가스 Sealing의 역할을 담당하는 부분으로서, 분리판의 부식은 이러한 특성의 저하 및 전해질의 소모를 유발시켜 MCFC의 내구성에 커다란 영향 을 미치는 요인으로 생각되고 있다. 이러한 배경으로부터 Uchida 그룹은 MCFC의 분라판 재료 의 부식거동을 계동적으로 검토하였다. 먼저 Fe에 Ni 과 Cr을 첨가한 재료를 산화성가스 분위기하에서 $(Li+K)CO_3$에 대하여 검토한 결과, Ni과 Cr 둘다 20wt%이상 첨가시, 내식성융 가지는 결 과를 보고하였다2) 이 경우 보호피막으로서 NiO 와 $LiCrO_2$가 작용하는데, $LiCrO_2$가 용융탄산염 중에서 보다 안정한 것으로 부터, Cr의 첨가가 내식성에 기여하는 것으로 판단하였다. 다음 단계 로서 Fe/Cr재료에 용-융탄산염 중에서 안정한 산화물을 형성하는 Al의 첨가효과를 검토하였다. Al의 첨가는 더욱 내식성을 향상시키는 것이 발견되었고, 약 4wt%의 첨가로 충분한 내식성을 가지 는 것을 보고 하였다. 그러나 이러한 안정한 산화물에 의한 내식성 향상은 전기진도도의 희생을 바탕으로 한 것으로서, 다읍 단계로서 Ti산화물의 반도체적인 특성을 이용하고자 제 4의 원소로서 Ti첨가를 시도하였다. 그러나 Fe/Cr/AVTi재료가 뛰어난 내식성을 가지는 것은 관찰되었으나, 전도도 향상에는 기여하지 못하는 것이 보고되었다. 현재 MCFC는 실용화를 위한 고성능화의 하나로서 가압하에서의 운전을 시도하고 있다. 이 러한 가압하에서의 운전은 기전력의 향상 및 전극반응의 촉진 등으로 출력의 향상을 가져오나. 현재 문제로 되고 있는 Cathode극인 NiO의 용해/석출 현상을 가속화하는 결과를 초래해, 이에대 한 대책으로서 Li-K보다 NiO의 용해가 적은 Li-Na탄산염으로의 전환이 진행되고 있다. 이러한 배경으로부터 Uchida그룹에서 개발한 FeiCr/AVTi재료와 현재 분리판 재료로 사용증인 SUS 310, S SUS 316재료에 대해. 산화성 분위기의 5기압까지의 가압하에서, Li-K, Li-Na탄산염에 대하여 부 식거동을 검토한 결과, 가압하에서 내식성이 향상되는 것이 발견되었다. 이유로서는 가압하에서 용융탄산엽의 증가된 산화력으로 보다 치밀한 내식성 산화물 피막이 형성되기 때문으로 생각되고 있다. 또한 Li-K, Li-Na탄산염에서의 부식의 정도에는 차이가 거의 없었으나, SUS 316의 경우 탄산염에 젖은 부분에서 내식성 피막이 형성되지 않는 이상부식현상이 관찰되었다. 재료간의 내식성 정도에서는 Fe/Cr/Al/Ti이 가장 내식성이 뛰어났으며, SUS 310 또한 뛰어난 내식성을 보였다.

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The Effect of Role Assignment on the Types and Patterns of Verbal Interactions in Middle School Students' Science Inquiry Activities (중학생의 과학 탐구 활동에서 역할 부여가 언어적 상호작용의 유형 변화와 양상에 미치는 영향)

  • Lim, Yu-jin;Kim, Youngshin;Lim, Soo-min
    • Journal of Science Education
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    • v.44 no.2
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    • pp.167-182
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    • 2020
  • The active participation and active interaction of learners in small group science inquiry activities are the main factors that determine the effectiveness of science learning. Roles can be assigned to members of a small group to facilitate interaction between members within the small group. The purpose of this study is to analyze the effect of role assignment on the types and patterns of verbal interactions in middle school students' small group science inquiry activities. For this, 172 students from middle schools located in metropolitan cities were surveyed. We analyzed 18 small groups with assigned roles and 15 small groups without assigned roles. The change in verbal interaction type in small group science inquiry activity according to role assignment was largely divided into alienation and participation. In the case of small groups with assigned roles, the participation type occupied a higher proportion than the alienation type. The change in verbal interaction patterns did not show much significant differences when the role was assigned in terms of cognitive and affective. Based on this, further research is needed on how role assignment affects verbal interactions depending on the type of scientific inquiry and the stage of inquiry. In addition, further research on the composition of small groups and role assignment is required.

Exploring the Triple Helix Innovation System in the Dutch Food Cluster(Food Valley) (네덜란드 라흐닝언 식품산업 클리스터(푸드밸리)의 트리플 힐릭스 혁신체계)

  • Lee, Chul-Woo;Kim, Tae-Yeon;Lee, Jong-Ho
    • Journal of the Korean association of regional geographers
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    • v.15 no.5
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    • pp.554-571
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    • 2009
  • This paper explores the triple helix innovation system in Food Valley in the Netherlands which is considered one of the most innovative food clusters in the world. The triple helix approach has been so far little tackled in the literature on innovation system and cluster. However, tills approach can be a useful tool for understanding the dynamic characters and knowledge transfer mechanism of industrial cluster. On the basis of an in-depth case study, we argue that Food Valley has evolved through four circles of growth in the triple helix innovation system. From the mid-2000s onward, it is seen that Food Valley has been on the stabilized circle in the triple helix system of innovation. Centered upon Wageningen UR, local universities and research centers play a pivotal role in building the triple helix innovation system. To cope with radical changes in markets and technology since the late 1980s, local firms have made a great deal of effort to reinforce the university-industry partnership. On the other hand, government agencies have played a critical role for establishing institutional milieu that facilitate university-industry partnerships and local knowledge transfer and spillover.

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Effect of ABA and Kinetin on Alleviating NaCl Injury during Rice Germination (ABA와 Kinetin 처리가 벼 발아중 NaCl 독성 경감에 미치는 효과)

  • 김상국;이상철;원종건;민기군;이승필;최부술
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.42 no.2
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    • pp.182-188
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    • 1997
  • The study was carried out to determine an optimum concentration of plant growth regulators(ABA and kinetin) on reducing NaCl toxicity during germination in rice. Plant height of a japonica cultivar Ilpumbyeo in ABA 10$^{-5}$ M was increased, while all treatments of kinetin had no clear effects on increasing the plant height. However, other rice cultivars showed slightly different reaction by PGRs compared with Ilpumbyeo. Germination rate of four rice cultivars was ranged from 53.1 to 58.2% in NaCl 1.3%. All treatments of kinetin accelerated germination rate of tested rice cultivars except Dasanbyeo compared with NaCl 1.3% treatment. The higher concentration of ABA and kinetin treatment induced the higher starch content, and while the lower concentration of two plant growth regulators induced the higher sugar content in all four rice cultivars. The free proline content of rice seedlings was highest in Ilpumbyeo among the tested cultivars under NaCl 1.3% treatment.

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