• Title/Summary/Keyword: 경시효과

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Studies on Management of Effective Temperature and Humidity in Greenhouse at Summer Season (하절기 효율적인 하우스 온도 습도 관리에 관한 연구)

  • 우영회;남윤일;송천호;김형준;김동억
    • Journal of Bio-Environment Control
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    • v.3 no.1
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    • pp.58-65
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    • 1994
  • It is necessary to effective temperature and humidity management for normal growth of crops in protected cultivation during the summer season. Because the highest temperature of vinyl house inhibit normal growth of crop and decrease of crop production or marketability in summer season. Finally, the vinyl house was impossible some crop cultivation in summer season. This study was conducted to investigate effective and economic method for temperature drop in protected cultivation during the summer season. 1. In medium size vinyl house(5$\times$13$\times$3m), the effect of temperature drop appeared the highest in treatment of shading with aluminium thermal curtain+fog system+ventilation with fan. The effect of temperature drop was about 1$0^{\circ}C$ lower than outer air temperature and about 4$^{\circ}C$ lower than outer soil temperature. 2. The effect of temperature drop according to shading with aluminium thermal curtain+fog system+ventilation with fan during the highest temperature of summer season Jul., 20 to Aug., 21 was appeared about 8$^{\circ}C$ lower than outdoor above ground(1.2m) and about 7$^{\circ}C$ lower than outdoor surface ground. 3. The changes of solar radiation during a day according to shading with aluminium thermal curtain+ventilation with fan and shading with black curtain+ventilation with fan treatments was appeared respectively about 29.3%, 32.5% of outdoor solar radiation a fine day and respectively about 27.4%, 31.8% of outdoor solar radiation a cloudy day.

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Development Feasibility of Water-Floating Fungicide Formulation for the Control of Sheath Blight(Caused by Rhizotonia solani) in Rice (수도(水稻) 문고병방제용(紋枯病防除用) 수면부유제(水面浮遊劑)의 개발(開發) 가능성(可能性)에 관(關)한 연구(硏究))

  • Oh, Byung-Youl;Kim, Jin-Hwa
    • Applied Biological Chemistry
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    • v.31 no.3
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    • pp.226-233
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    • 1988
  • Some physico-chemical properties and biological activities of new fungicide formulations were tested to investigate a feasibility of water-floating formulation development for sheath blight control in rice. Pencycuron[1-(4-chlorobenzyl)-1-cyclopentyl-3-phenylurea] and flutolanil$({\alpha},{\alpha},{\alpha}$-trifluoro-3'-isopropoxy-O-toluanilide) were chosen as toxicants for the formulations. Vegetable oil and surface active agents were used as a floating agent and spreader, respectively. All the formulations tested showed an excellent spreadability on the water having over $35cm^2/mg$ and were chemically stable, which the degradation rates of active ingredients were less than 10% after 12 weeks of storage at $50^{\circ}C$. Most of the applied test formulation of pencycuron was retained within 0.5cm of the surface paddy water, while that of flutolanil was vertically dispersed in the water. Inhibition activity of the tested pencycuron formulation on the sclerotia germination of the pathogen in paddy water was maintained over 30 days after the formulation treatment. Control effect of 4% pencycuron water-floating formulated with surface active agent of hydro-lipophyllic balance 4.3 on the disease in rice was equal to the reference fungicide(pencycuron 25% WP) when the former was treated one day before the transplantation of rice seedlings. Overflowing the submerged paddy water after the formulation treatment resulted in a deterious effect on the disease control.

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사이버 시대의 윤리 교육 : 청소년을 중심으로

  • 류나정;고석하
    • Proceedings of the Korea Society for Industrial Systems Conference
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    • 2002.06a
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    • pp.417-424
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    • 2002
  • 컴퓨터는 인간의 모든 꿈과 희망을 실현시켜 줄 수 있는 마법상자는 아니다. 정보화 시대라고 일컫는 현재, 정보의 가치를 더해주는 컴퓨터의 중요성은 날로 커지고 있는 반면 인간의 존엄성은 경시되고 있다. 많은 사람들은 요즘 사회가 커다란 도덕적 위기에 빠졌다고 걱정하지만 컴퓨터 사용과 관련된 윤리적 문제에 대해서는 심각하게 느끼지 못하고 있는 것 같다. 정보통신 기술의 발달에 따라 새로운 교육의 필요성이 대두되고 있다. 기존의 전통적인 교육방식에서 사이버 윤리 교육은 교과서 중심의 단편적인 교육이었기 때문에 학습자의 흥미를 유발하지 못하였으며, 교육자와 학습자의 상호작용이 부족하여 사이버 윤리 교육의 효과가 미흡하였다. 정보통신 기술의 발달에 따라 새로운 교육의 필요성이 대두되고 있다. 기존의 전통적인 교육방식에서 사이버 윤리 교육은 교과서 중심의 단편적인 교육이었기 때문에 학습자의 흥미를 유발하지 못하였으며, 교육자와 학습자의 상호작용이 부족하여 사이버 윤리 교육의 효과가 미흡하였다. 이런 관점에서 본 논문은 정보통신 시대가 수반하고 있는 사회적 영향력과 윤리적 이슈들에 대하여 좀더 교육적인 측면으로 접근해 윤리교육의 현황과 문제점, 그리고 체계적인 확산방안에 대해 살펴보았다. 본 논문에서는 사이버공간에서 윤리 교육을 받는 청소년들을 중심으로 그들에게 새로운 윤리교육의 한 형태인 사이버공간에서 관련된 문제들을 교육적인 측면으로 해결할 수 있는 방안을 제시하고자 한다. 그러나, 무엇보다 우리가 명심해야 할 것은 인간의 존엄성은 그 어떤 이유를 막론하고 존중되어야 한다는 사실이다. 검증되지 않은 스토리 보드에 의한 저작 단계로 바로 돌입하고 있는 것이 한국의 실정이라 하겠다. 따라서 본 프로젝트에 의해 개발 된 교수 설계 도구는 교육/학습 컨텐츠의 품질 보증을 위한 방법론인 교육 공학의 체제적 교수 설계 이론 Model (Instructional System Design Model), 특히 그 중에서도 이 분야의 사실상의 표준 이론(de facto standard)인 Dick & Carey 교수와 Gagne 교수의 인지주의 ISD Model을 기반으로 정교한 교수 설계와 코스 맵 설계를 가능하게 함으로써 학습 컨텐츠의 품질 보증 활동을 지원 할 수 있는 도구로 개발하였다. 특히 Linux 기반에서 PHP로 개발 함으로써 Platform에 구애받지 않은 사용 환경을 구현 하였으며 향후 많은 e-Learning Platform에 교수 설계 모듈로 장착 함으로써 기존의 e-Learning Platform들의 가치를 높일 수 있는 계기가 될 것으로 생각한다.실징후를 파악하는데 그치지 않고 부실의 원인을 파악하고 이에 대한 대응 전략을 수립하며 그 결과를 측정하는데 활용될 수도 있다. 따라서 본 연구에서는 기업의 부도예측 정보 중 현금흐름정보를 통하여 '인터넷기업의 미래 현금흐름측정, 부도예측신호효과, 부실원인파악, 비즈니스 모델의 성격규정 등을 할 수 있는가'를 검증하려고 한다. 협력체계 확립, ${\circled}3$ 전문인력 확보 및 인력구성 조정, 그리고 ${\circled}4$ 방문보건사업의 강화 등이다., 대사(代謝)와 관계(

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In vitro Response of the MPO System of the Clam, Coelomactra antiquata with Exposure to Cytochrome P450 Inducers (Cytochrome P450 유도제에 노출시킨 명주조개 (Coelomactra antiquata) 약물대사효소계의 in vitro 반응)

  • Jeon Joong Kyun;Lee Mee Hee;Shim Won Joon;Lee Soo Hyung
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.2
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    • pp.179-184
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    • 2002
  • Induction of cytochrome P45O (CYP) and 7-etholqresorufin-O-deethylase (EROD) in the microsome exposed to 3-methylcholan-throne (MC), $\beta$-naphthoflavone (BNF) and phenobarbital-Na (PB) was investigated, Microsome was isolated from digestive gland of clam (Coelomactra antiquata) and then exposed to each chemical in concentration range of 0.1 to 1.0 mM for 7 hours. The CYP content and EROD activity in the microsome exposed to each chemical significantly increased compared to the control group. The overall CYP and EROD induction potency was in order of MC>BNF>PB. The induction response of EROD was two times higher than that of CYP level in the microsome exposed to MC, but the induction response of EROD was slightly higher than that of CYP level in BNF and PB exposure groups.

Mechanism improvement of the heat exchanger and the ventilator for the thermal efficiency increment of hot-air heater (온풍난방기의 열이용효율 증대를 위한 열교환부 및 송풍기 구조개선)

  • 이기명;박규식;최성우
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 2002.02a
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    • pp.558-563
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    • 2002
  • 시설원예에서 난방장치를 사용하는 겨울철 재배 농산물의 생산비 중 난방 연료비가 30%~37% 정도를 차지하여 비중이 가장 높다. 따라서 시설원예 농가에서는 난방비를 절감하는 것이 농가소득과 직결되므로, 난방장치의 선정이 대단히 중요하다. 본 연구에서는 겨울철 재배 농산물의 생산비 중 30%-37% 정도를 차지하는 연료비를 절감하기 위해 기존의 온풍난방기와 다른 새로운 방식의 열교환기와 원심식 송풍블로워를 사용하는 블로워 송풍방식의 온풍난방기를 개발하고 개발된 온풍난방기의 가동으로 인한 난방 연료비 절감효과와 온실내의 균일한 온도분포를 획득하기 위해 8연동 비닐온실에서의 시험을 실시하였으며 얻어진 결과를 요약하면 다음과 같다. 가. 저 정압용의 전동기 축직결식 송풍팬을 대신하여 고 정압용의 블로워 송풍팬을 장착하고 열교환 면적을 크게 한 지그재그식 환류의 열교환실을 채용한 온풍난방기를 개발하였다. 나. 공시한 온실에서 기존 온풍난방기의 2일 가동시 DH당 연료 사용량이 평균 1.082$\ell$/$^{\circ}C$.hr 이며, 블로워 송풍방식 온풍난방기의 3일 가동시 DH당 연료 사용량은 평균 0.854$\ell$/$^{\circ}C$.hr로써 21%의 난방 연료비 절감효과가 나타났다. 다. 블로워 송풍방식 온풍난방기는 동일시간대 3$^{\circ}C$의 경시적 온도변화가 발생하였고, 기존의 은풍난방기의 동일시간대 온도변화는 최대 6.1$^{\circ}C$로 나타나 개발된 블로워 송풍방식 온풍난방기가 동일시간대 온실내의 온도변화를 크게 줄일 수 있었고 온도분포를 비교적 균일하게 하는 효과가 있음을 확인하였다.도 33$^{\circ}C$를 기준으로 한 열 회수 시간은 유입공기 온도가 52$^{\circ}C$ 및 64$^{\circ}C$ 일 각각 120분 및 140분으로 나타났다. (3) 제 3종 자갈: 축열조로 공급되는 공기의 온도가 52$^{\circ}C$와 64$^{\circ}C$ 일 때, 축열조 출구의 공기온도가 33$^{\circ}C$에 도달될 때까지 가열되는데 소요된 시간은 가열공기의 온도가 52$^{\circ}C$와 64$^{\circ}C$ 일 때 각각 180분과 150분이었고, 방열에 소요된 시간은 각각 240분 및 270분으로 나타났다. 방열과정 동안 축열조 출구의 최고 공기온도는 가열 공급공기의 온도가 52$^{\circ}C$$65^{\circ}C$일 때 각각 35.5$^{\circ}C$ 및 39.5$^{\circ}C$였다. 출구 공기온도 33$^{\circ}C$이상을 기준으로 한 에너지 회수시간은 유입공기 온도가 52$^{\circ}C$ 및 64$^{\circ}C$일 때 각각 140분 및 160분으로 나타났다. 이와 같이 자갈이 작을수록 축열조 출구의 공기온도가 기준온도 33$^{\circ}C$에 도달되는 시간이 길었으며, 이것은 축열조내의 공극이 작고 비중량이 커 자갈층을 가열시키는 축열시간이 길어지기 때문인 것으로 사료된다. 또한 작은 자갈일수록 방열시간도 다소 길어져 회수 가능 열에너지가 큰 것으로 나타났다

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Changes in Physicochemical Properties and Bioactivity of Pesticide Spray Solutions (농약살포액의 이화학적 특성과 생물활성 변화)

  • Jin, Yong-Duk;Lee, Sang-Bum;Lee, Sang-Guei;Oh, Byung-Youl
    • The Korean Journal of Pesticide Science
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    • v.9 no.4
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    • pp.411-421
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    • 2005
  • This study was carried out to establish rational methodologies for the use of pesticide formulations to be sprayed after water-dilution. Hardness and electric conductivity of six major river water and ground water sampled from 52 sites in major rice-growing areas across the country ranged from 5 to 324 ppm(av. 90 ppm) and from 0.038 to 1.078 dS/m(av. 0.265 dS/m), respectively, which are acceptable for diluent water of pesticides. The pH changes in pesticide spray solutions with time after preparation mainly depended on the pH of the water used for pesticide dilution. The surface tensions of pesticide spray solutions reduced slightly with time after preparation, irrespective of kinds of pesticide formulations. Suspensibility of WPs became worse with an increase in the hardness and salt concentrations of diluent water, even though the degree was negligible. Emulsion stability of ECs became worse with an increase in hardness and salt concentrations of diluent water. Degradation rates of the active ingredients of pesticide spray solutions 3 days after preparation were less than 5%, regardless of mixing or non-mixing of two or more pesticides. Consequently, the spray solutions of most pesticides were usable until two to three days after preparation unless physical properties deteriorated. The tank-mixing order of EC and WP formulations did not make any differences in all the physical properties of pesticide spray solutions. However, the proper order for the tank-mixing of compatible pesticides was WP, WG, SC, EC, and SL, because the order is easy to prepare the pesticide spray solutions. The efficacy of pesticide spray solutions on the respective target pathogens and insect pests of rice plants three days after preparation was recorded over 95% of that of 0 day, which was almost the same as that of the solutions applied punctually after preparation.

In Vitro Antibacterial Effect of the Combination of Galla rhois ethanol extracts and Sodium chlorate against Intramacrophage Brucella abortus

  • Cha, Chun-Nam;Hong, Il-Hwa;Yu, Eun-Ah;Park, Eun-Kee;Yoo, Chang-Yeol;Kim, Suk;Lee, Hu Jang
    • Journal of Food Hygiene and Safety
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    • v.29 no.1
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    • pp.67-72
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    • 2014
  • This study investigated the antibacterial effects of GR ethanol extracts (GRE), sodium chlorate (SC) and a combination of GRE and SC (GS) on Brucella abortus (B. abortus). The antibacterial activities of GRE, SC and GS towards B. abortus were evaluated by incubating B. abortus with GRE, SC and GS. Following treatment with GRE, SC and GS, B. abortus survival and intracellular proliferation in macrophages were monitored. In the cellular cytotoxicity assay, GRE, SC and GS are not cytotoxic at concentrations less than $400{\mu}g/ml$, 15 mM and 0.6GS (1 of GS, GRE $1,000{\mu}g/ml$ + SC 30 mM), respectively. The viability of B. abortus was markedly decreased in a dose-dependent manner in all treatment groups. In addition, B. abortus intracellular proliferation within macrophages was significantly reduced in cells treated with GRE ($400{\mu}g/mL$), SC (15 mM) and 0.5GS (GRE $500{\mu}g/mL$ + SC 15 mM) after 48 hr-incubation (GRE, p < 0.01; SC and 0.5GS, p < 0.001). Especially, in the treatment of GS, the synergistic effect of GRE and SC treatment on B. abortus in macrophage was observed. In conclusion, GS is useful as an antibacterial candidate against B. abortus, and can be applied in the field of meat and milk hygiene.

Experimental study on ultra-high strength concrete(130 MPa) (초고강도 콘크리트(130MPa)에 대한 실험적 연구)

  • Cho Choonhwan;Yang Dong-il
    • Journal of the Korea Institute of Construction Safety
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    • v.6 no.1
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    • pp.12-18
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    • 2024
  • High-rise, large-scale, and diversification of buildings are possible, and the reduction of concrete cross-sections reduces the weight of the structure, thereby increasing or decreasing the height of the floor, securing a large number of floors at the same height, securing a large effective space, and reducing the amount of materials, rebar, and concrete used for designating the foundation floor. In terms of site construction and quality, a low water binder ratio can reduce the occurrence of dry shrinkage and minimize bleeding on the concrete surface. It has the advantage of securing self-fulfilling properties by improving fluidity by using high-performance sensitizers, making it easier to construct the site, and shortening the mold removal period by expressing early strength of concrete. In particular, with the rapid development of concrete-related construction technology in recent years, the application of ultra-high-strength concrete with a design standard strength of 100 MPa or higher is expanding in high-rise buildings. However, although high-rise buildings with more than 120 stories have recently been ordered or scheduled in Korea, the research results of developing ultra-high-strength concrete with more than 130 MPa class considering field applicability and testing and evaluating the actual applicability in the field are insufficient. In this study, in order to confirm the applicability of ultra-high-strength concrete in the field, a preliminary experiment for the member of a reduced simulation was conducted to find the optimal mixing ratio studied through various indoor basic experiments. After that, 130 MPa-class ultra-high-strength concrete was produced in a ready-mixed concrete factory in a mock member similar to the life size, and the flow characteristics, strength characteristics, and hydration heat of concrete were experimentally studied through on-site pump pressing.

Field Applicability Evaluation Experiment for Ultra-high Strength (130MPa) Concrete (초고강도(130MPa) 콘크리트의 현장적용성 평가에 관한 실험)

  • Choonhwan Cho
    • Journal of the Society of Disaster Information
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    • v.20 no.1
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    • pp.20-31
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    • 2024
  • Purpose: Research and development of high-strength concrete enables high-rise buildings and reduces the self-weight of the structure by reducing the cross-section, thereby reducing the thickness of beams and slabs to build more floors. A large effective space can be secured and the amount of reinforcement and concrete used to designate the base surface can be reduced. Method: In terms of field construction and quality, the effect of reducing the occurrence of drying shrinkage can be confirmed by studying the combination of low water bonding ratio and minimizing bleeding on the concrete surface. Result: The ease of site construction was confirmed due to the high self-charging property due to the increased fluidity by using high-performance water reducing agents, and the advantage of shortening the time to remove the formwork by expressing the early strength of concrete was confirmed. These experimental results show that the field application of ultra-high-strength concrete with a design standard strength of 100 MPa or higher can be expanded in high-rise buildings. Through this study, we experimented and evaluated whether ultra-high-strength concrete with a strength of 130 MPa or higher, considering the applicability of high-rise buildings with more than 120 floors in Korea, could be applied in the field. Conclusion: This study found the optimal mixing ratio studied by various methods of indoor basic experiments to confirm the applicability of ultra-high strength, produced 130MPa ultra-high strength concrete at a ready-mixed concrete factory similar to the real size, and tested the applicability of concrete to the fluidity and strength expression and hydration heat.

Analysis of Effectiveness for Water Cycle and Cost-Benefit according to LID Application Method in Environmentally-Friendly Village (친환경시범마을의 LID 적용에 따른 물순환 효과 및 비용편익 분석)

  • Baek, Jongseok;Lee, Sangjin;Shin, Hyunsuk;Kim, Hyungsan
    • Journal of Korean Society on Water Environment
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    • v.34 no.1
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    • pp.57-66
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    • 2018
  • Water disasters such as flash floods and inundation caused by localized heavy rainfall in urban areas have a large impact on climate change but are also closely related to the increase in impervious areas as pointed out in domestic and international studies. It is difficult to secure natural green areas in urban areas that have already been developed. So, urban regeneration can be expected using water management optimized with technologies to secure infiltration and storage capacity such as Low-Impact Development technology. In this study, the water cycle improvement ability was confirmed by applying the LID technology within the district unit plan of the environmentally friendly village, and the economic feasibility of LID application was analyzed by estimating the costs and benefits of installing the facilities. The site was planned to conserve sufficient green and plans for securing the watershed infiltration and storage capacity were formulated with the application of additional LID technology, such as infiltration trenches, rain barrels and permeable pavements. The LID design method applicable to the site was established, and the water balance of the watershed was analyzed through simulations of the SWMM model. The water circulation improvement effect was confirmed through the water balance analysis, and the cost-benefits were determined according to the estimation method, and the economic analysis was conducted. This study confirms that the investment of LID technology is economically feasible for the hydrological improvement effect of the housing complex.