• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.627-627
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• 2013

Recently, most studies concerning inorganic CdSe/ZnS quantum dot (QD)-polymer hybrid LEDs have been concentrated on the structure with multiple layers [1,2]. The QD LEDs used almost CdSe materials for color reproduction such as blue, green and red from the light source until current. However, since Cd is one of six substances banned by the Restriction on Hazardous Substances (RoHS) directive and classified into a hazardous substance for utilization and commercialization as well as for use in life, it was reported that the use of CdSe is not suitable to fabricate a photoelectronic device. In this work, we demonstrate a novel, simple and facile technique for the synthesis of ZnO-graphene quasi-core.shell quantum dots utilizing graphene nanodot in order to overcome Cd material including RoHS materials. Also, We investigate the optical and structural properties of the quantum dots using a number of techniques. In result, At the applied bias 10 V, the device produced bluish-white color of the maximum brightness 1118 cd/$m^2$ with CIE coordinates (0.31, 0.26) at the bias 10 V.

• 한국물환경학회지
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• 제31권4호
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• pp.407-417
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• 2015

Soil loss is one of the significant disasters which have threatened human community and ecosystem. Particularly, Korea has high vulnerability of soil loss because rainfall is concentrated during summer and mountainous regions take more than 70% of total land resources. Accordingly, the sediment control management plan are required to prevent the loss of soil resources and to improve water quality in the receiving waterbodies. In this regard, the objectives of this study are 1) to quantify the effect of the Vegetative Filter Strip (VFS) on sediment runoff reduction and 2) to analyze the relationship of rainfall intensity and sediment runoff. For this, SATEEC and VFSMOD were used to estimate sediment runoff according to rainfall intensity and to quantify the effect of VFS on sediment runoff reduction, respectively. In this study, the VFS has higher impact on sediment reduction for lower maximum rainfall intensity, which means that the maximum rainfall intensity is one of significant factors to control sediment runoff. Also, the sediment with VFS considered was highly correlated with maximum rainfall intensity. For these results, this study will contribute to extend the applicability of VFS in establishing eco-friendly sediment control plans.

• 자동차안전학회지
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• 제12권2호
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• pp.7-13
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• 2020

Recently, there is a big issue of downsizing on brake system according to fuel efficiency and regenerative braking cooperation control. Especially, small cars have improved in a variety ways such as electric vehicle and smart car compared to previous small cars. So, small brake system is strongly required in the car industry. A new small brake system for light compact vehicles was proposed in this paper. For this system, the solid type disc and caliper were newly developed. And the important design factors were considered to reduce brake size. First, we calculated the temperature rise of disc through heat capacity formula and CAE analysis. Second, we analyzed the housing and carrier stiffness of caliper to select the reasonable condition. Finally, the superiorities of the developed brake system were verified by heat capacity, consumption liquid level, braking feeling, judder, wear test and regenerative braking cooperation control analysis. A developed brake system is expected to be useful for brake system of light compact platform.

• International Journal of Industrial Entomology and Biomaterials
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• 제14권2호
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• pp.81-85
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• 2007

White Muscardine is the most common fungal disease of silkworm, Bombyx mori L. caused by the pathogenic fungus, Beauveria bassiana (Balsamo) Vuillemin. In the present investigation, an attempt has been made to screen locally available medicinal/ weed plants against Beauveria bassiana. Among the plant extracts (PE) tested, 5% aqueous crude extract of the bulb of Allium sativum (Garlic) has been found to be most effective against Beauveria bassiana. The radial growth of Beauveria bassiana in vitro was inhibited to the tune of 54.9% in aqueous extract and 54.4% in ethanolic extract of Allium sativum and correspondingly mycelial dry weight gave rise to 110.7 mg and 108.7 mg against 201.7 mg in control 15 days post treatment. Similarly, silkworm larvae topically inoculated with the Beauveria bassiana conidia ($1.8{\times}10^6/ml$) registered survival up to 53.0% against 0.0% in control after treatment with aqueous extract of Allium sativum. Simultaneously, as a preventive measure, silkworm larvae were put to rear in conidia contaminated seat paper instantly treated with aqueous extract of Allium sativum that also increased survival up to 61.0% against 4.6% in control. It is also observed that the plant extract is absolutely innocuous to silkworm.

• 해양환경안전학회지
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• 제28권6호
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• pp.1013-1022
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• 2022

최근 전세계적으로 4차산업이 발전함에 따라 스마트·친환경 선박의 기술 개발이 가속화 되고 있다. 완전 무인화 또는 최소인원이 승선하는 자율운항선박과 친환경 연료(메탄, 암모니아, 전기 등) 이용 선박이 등장하게 되면서 선박에 승선을 하고 있는 기존 해기사의 역할이 크게 변화될 것으로 예상되고 있다. 향후 해기사의 경쟁력을 향상시키기 위해서는 미래 해기사 직업군을 예측하고 그에 맞는 교육 커리큘럼 개선과 교육환경 조성이 필요할 것으로 생각된다. 본 연구에서는 선행연구 검토와 해양계 대학교 재학생, 현직 해기사, 전문가의 브레인스토밍을 통해 미래에 해기사가 가질 수 있는 8개의 직업군을 도출한 후 리커트 척도를 이용하여 설문을 실시하였고, 그 결과를 바탕으로 미래 해기사 관련 유력 직업군을 도출하였다. 분류한 8개 직업군 중 가장 유력한 직업군은 자율운항선박 육상제어사, 화물(적양하) 원격 관리자로 나타났다. 또한, 이러한 직업군들과 4차산업에 우선적으로 교육해야 할 필수 교육 요소를 도출하여 제시하였다.

• 한국조경학회지
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• 제34권4호
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• pp.84-95
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• 2006

This study begins by examining the reason for the lack of urban planning that takes the water cycle into consideration. While there are institutions that support environmentally friendly development or smooth water circulation, these designs are not reflected in planning nor in the real world. After reviewing foreign case studies, policy suggestions and possible policy implications for Korea are derived. In Korea, there is not a sufficient level of relevant laws or institutions systematically established to make it possible to deal with rainwater in a decentralized way. Instead, facility standards or guidelines are considered separately for the control of water and for preventing natural disasters. And even though an environmentally friendly approach is stipulated in relevant laws in terms of spatial planning, there are no planning systems or implementation tools to actualize this kind of approach. The factors that make decentralized rainwater management possible in urban planning are analyzed based on the case study of Germany. Germany requires developers to plan in order to achieve ecological urban development. In addition, as a detailed implementation tool to promote conservation of the water cycle, the law provides for various kinds of measures such as restrictions on the proportion of impervious surface area according to the use of the land, required compensation measures for environmental degradation following development, introduction of a fee for rainwater runoff and the establishment of ecological landscape planning. The actual reason these measures can be implemented however is the provision of planning guidelines and design criteria for rainwater utilization, absorption and containment, and the construction of a database for various environmental information.

• 전력전자학회논문지
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• 제15권3호
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• pp.188-198
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• 2010

최근들어, 전기이중층 커패시터 등의 친환경 전력저장장치의 수요가 증가하면서, 이를 위한 양방향 충/방전기의 수요 또한 증가하고 있다. 그러나, 기존의 상용화된 아날로그 제어기를 사용하는 DC-DC 컨버터를 충 방전기로 사용하게 되면, 충/방전 레퍼런스를 제공하는 상위 디지털 제어기와 별도로 아날로그 제어기를 제작해야 하는 문제가 있고, 회로가 복잡해지며, 모드전환 시 과도응답이 좋지 않다. 이에 대한 대안으로 단일 디지털 제어기를 사용하게 되면 쉽게 구현 가능한 설계방식을 이용하여 양방향 시스템의 성능을 향상 시킬 수 있다. 본 논문에서는 단일 회로 단 양방향 벅-부스트 컨버터에 전기이중층 콘덴서를 이용한 친환경 전력저장장치의 양방향 충/방전 시스템을 구현하고, DSP(TI사 TMS320F28335)를 이용한 디지털 제어기를 적용하였다. MATLAB simulink를 이용하여 모의실험을 수행하였고, 하드웨어를 구성하여 실험한 결과, 모의실험과 마찬가지로 양방향 시스템의 응답특성이 개선되었음을 보여주었다.

• The Plant Pathology Journal
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• 제36권4호
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• pp.335-345
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• 2020

Tomato grey mould has been one of the destructive fungal diseases during tomato production. Ten mM of menadione sodium bisulfite (MSB) was applied to tomato plants for eco-friendly control of the grey mould. MSB-reduced tomato grey mould in the 3rd true leaves was prolonged at least 7 days prior to the fungal inoculation of two inoculum densities (2 × 10⁴ and 2 × 10⁵ conidia/ml) of Botrytis cinerea. Protection efficacy was significantly higher in the leaves inoculated with the lower disease pressure of conidial suspension compared to the higher one. MSB-pretreatment was not effective to arrest oxalic acid-triggered necrosis on tomato leaves. Plant cell death and hydrogen peroxide accumulation were restricted in necrotic lesions of the B. cinereainoculated leaves by the MSB-pretreatment. Decreased conidia number and germ-tube elongation of B. cinerea were found at 10 h, and mycelial growth was also impeded at 24 h on the MSB-pretreated leaves. MSB-mediated disease suppressions were found in cotyledons and different positions (1st to 5th) of true leaves inoculated with the lower conidial suspension, but only 1st to 3rd true leaves showed decreases in lesion sizes by the higher inoculum density. Increasing MSB-pretreatment times more efficiently decreased the lesion size by the higher disease pressure. MSB led to inducible expressions of defence-related genes SlPR1a, SlPR1b, SlPIN2, SlACO1, SlChi3, and SlChi9 in tomato leaves prior to B. cinerea infection. These results suggest that MSB pretreatment can be a promising alternative to chemical fungicides for environment-friendly management of tomato grey mould.

• The Plant Pathology Journal
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• 제33권3호
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• pp.337-344
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• 2017

To develop a commercial product using the mycoparasitic fungus Simplicillium lamellicola BCP, the scale-up of conidia production from a 5-l jar to a 5,000-l pilot bioreactor, optimization of the freeze-drying of the fermentation broth, and preparation of a wettable powder-type formulation were performed. Then, its disease control efficacy was evaluated against gray mold diseases of tomato and ginseng plants in field conditions. The final conidial yields of S. lamellicola BCP were $3.3{\times}10^9conidia/ml$ for a 5-l jar, $3.5{\times}10^9conidia/ml$ for a 500-l pilot vessel, and $3.1{\times}10^9conidia/ml$ for a 5,000-l pilot bioreactor. The conidial yield in the 5,000-l pilot bioreactor was comparable to that in the 5-l jar and 500-l pilot vessel. On the other hand, the highest conidial viability of 86% was obtained by the freeze-drying method using an additive combination of lactose, trehalose, soybean meal, and glycerin. Using the freeze-dried sample, a wettable powder-type formulation (active ingredient 10%; BCP-WP10) was prepared. A conidial viability of more than 50% was maintained in BCP-WP10 until 22 weeks for storage at $40^{\circ}C$. BCP-WP10 effectively suppressed the development of gray mold disease on tomato with control efficacies of 64.7% and 82.6% at 500- and 250-fold dilutions, respectively. It also reduced the incidence of gray mold on ginseng by 65.6% and 81.3% at 500- and 250-fold dilutions, respectively. The results indicated that the new microbial fungicide BCP-WP10 can be used widely to control gray mold diseases of various crops including tomato and ginseng.

• Weed & Turfgrass Science
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• 제4권3호
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• pp.219-224
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• 2015

본 연구를 통해 토양 방선균 유래 제초활성물질을 대상으로 제초제로서의 적용 가능성 여부를 확인하기 위하여 수행되었다. 잡초에 대한 발아와 경엽처리에 대한 약효시험 결과, 종자 발아는 100 ppm 수준으로 처리하고 경엽에는 2,000 ppm 수준으로 처리해야 저해효과를 나타냈다. 작물에 대한 시험 결과, 오이는 발아억제가 이루어지지 않았으며 벼는 발아와 생육 모두 50% 내외의 저해를 보였다. 그 외의 모든 시험 작물 초종은 처리 농도에 따른 민감한 반응을 보였다. 즉 토양방선균으로부터 발굴한 천연제초활성물질은 선택성 제초제로의 개발은 어려워 보이나 비선택성 제초제로의 개발은 가능할 것으로 보인다. 한편 처리방법에 따른 농도별 시험 결과, 패트리디쉬에서 실험의 경우 모든 잡초종이 농도에 민감히 반응하였으며, $GR_{50}$값은 1-2 ppm 정도를 보였다. 그리고 토양처리 효과에 따른 발아억제 및 생육저해 효과는 쌍떡잎식물에서 보다 민감한 반응을 보였고, 털비름의 경우 1,000 ppm에서도 85%의 생육저해를 보였다. 경엽처리에 따른 생육저해 조사시 2,000 ppm에서 피는 고사하지 않았으나 나머지 초종은 모두 고사하였고, 특히 털비름은 6.25 ppm의 농도에서도 고사하였다. 경엽처리에 따른 대표적인 반응으로 바랭이는 잎의 꼬임현상을 나타냈고, 어저귀는 잎이 변색되었다. 토양처리는 그 효과가 경미하고 일정기간 경과후에 재생되어 방제효과가 부족하였으며, 경엽처리의 경우 피를 제외한 잡초종등이 2,000 ppm에서 방제가 가능할 것으로 보인다. 또한 모든 결과를 종합 할 때 화본과잡초 보다 광엽잡초에서 민감한 발아억제 및 생육저해 효과를 볼 수 있었다. 따라서 토양 방선균 유래 제초활성 후보물질은 비선택성 경엽처리제로서의 개발이 상대적으로 유망할것으로 판단되었다. 한편 화본과 잡초에 대한 저해 효과가 부족함으로 추후 다른 제제와 혼합함으로써 화본과 잡초도 동시에 방제할 수 있는 기술의 개발이 필요할 것이다.