• 대한전기학회논문지:전력기술부문A
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• 제48권12호
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• pp.1498-1506
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• 1999

In this paper, a hybridization of Evolutionary Strategy (ES) and a Two-Phase Neural Network(TPNN) is applied to the optimal environmental and economic operation. As the evolutionary computation, ES is to search for the global optimum based on natural selection and genetics but it shows a defect of reducing the convergence rate in the latter part of search, and often does not search the exact solution. Also, neural network theory as a local search technique can be used to search a more exact solution. But it also has the defect that a solution frequently sticks to the local region. So, new algorithm is presented as hybrid methods by combining merits of two methods. The hybrid algorithm has been tested on Emission Constrained Economic Dispatch (ECED) problem and Weighted Emission Economic Dispatch (WEED) problem for optimal environmental and economic operation. The result indicated that the hybrid approach can outperform the other computational efficiency and accuracy.

• 한국수소및신에너지학회논문집
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• 제24권6호
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• pp.566-572
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• 2013

In the present study, structure analysis has been performed to understand the deflection and stress distribution for a hybrid street-lamp having a vertical-axis wind turbine and a photovoltaic panel. Modal analysis is also evaluated to avoid resonance gerenerated by sychronism between a turbine and a lamppost. To analyze deflection, stress and frequency, general analysis code(ANSYS-Mechanical 13) is employed in the present work. Throughout structure analysis in the hybrid street-lamp, maximum stress is observed at the connecting position between a turbine blade and a blade supporter. Campbell diagram which is combined the natural frequency of turbine blades and blade passing frequency is presented to analyze a system resonance. It is found that the resonance of the system having a rotating turbine blade and a lamppost can avoid by the optimal selection of geometric parameters of a wind turbine.

• 식물분류학회지
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• 제45권4호
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• pp.362-368
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• 2015

꼬리고사리속의 두 개의 신교잡종과 한 개의 미기록교잡종이 발견되었다. 이들 종들의 형태적 형질에 있어 부모종들의 중간형태를 보였다. 거미사철고사리($A.{\times}uiryeongse$)는 서울 북한산 우이령길에서 발견되었고 거미고사리와 사철고사리의 교잡에 의해 분화되었다. 다른 교잡종, 산꼬리고사리($A.{\times}montanus$)는 경기도 연천군, 성산에서 발견되었고, 거미고사리와 차꼬리고사리가 교잡에 의해 만들어지고 다시 꼬리고사리와의 중복교잡에 의해 형성되었다. 아울러 미기록 교잡종인 거미돌담고사리($A.{\times}kitazawae$)는 대구 도동에서 발견되었고, 거미고사리와 돌담고사리의 교잡에 의해 형성되었다. 이들 교잡종들은 부모종들과 같은 장소에서 자란다. 각 분류군의 형질을 분석해 교잡종임을 입증해 보였으며, 이들에 대한 기재, 도해 및 자생지의 서식 사진을 수록하였다.

• 한국구조물진단유지관리공학회 논문집
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• 제21권3호
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• pp.45-53
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• 2017

대형복합재난은 자연재난과 사회재난이 연쇄적 또는 동시다발적으로 발생함에 따라 예측 가능한 범위 밖의 거대한 규모로 전개되는 재난을 의미한다. 대형복합재난은 재난의 동시성과 연쇄성으로 전혀 새로운 형태로 변화되어 기존의 재난관리방식과 다른 새로운 관리방식이 필요하게 된다. 이에 본 연구는 대형복합재난을 대상으로 선진외국의 복합재난대응체계를 검토하여 국내 복합재난 대응체계에 필요한 정책적 개선방향을 제시하였다.

• 대한심미치과학회지
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• 제8권1호
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• pp.46-59
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• 1999

A fixed bridge is preferred as a prosthetic option supported by oral implants. However, it is very difficult to re tore edentulous maxilla with fixed prosthesis in cases with improper position and angulation of fixtures, abnormal jaw relation, and need for proper lip support. Six Br${\aa}$nemark implants were installed in edentulous maxilla opposing mandible with natural dentition. A removable hybrid prosthesis attached to a bar milled by 6 degrees was therefore designed to overcome such disadvantages of fixed prosthesis. Lateral stabilization of removable prosthesis was obtained by framework closely fitting the milled bar. Support for the prosthesis was ensured by three elevated areas on the bar. Two precision attachments(CEKA REVAX) provided appropriate direct and indirect retention without influencing support. A clinical and laboratory procedure was presented.

• 식물분류학회지
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• 제49권4호
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• pp.282-293
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• 2019

Broussonetia × kazinoki Siebold has long been utilized as a major component in the manufacturing of Korean traditional paper, hanji, and has been suggested as a hybrid species of B. papyrifera and B. monoica. By applying three molecular markers, chloroplast (cp) ndhF-rpl32 IGS, a nuclear ribosomal internal transcribed spacer, and the TOPO6 gene, the hybrid origin of B. × kazinoki is tested. As a result, B. × kazinoki in Korea is demonstrated to be a hybrid of B. monoica × B. papyrifera, most likely formed naturally in Korea. The cp haplotypes detected provided information about the origins and genetic diversity of the maternal lineage B. monoica and paternal lineage B. papyrifera. The two nuclear markers were supplemented to each other, leading to the discovery of introgression in Broussonetia.

• Corrosion Science and Technology
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• 제16권2호
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• pp.85-89
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• 2017

One of the most challenging issues in the oil and gas industry is corrosion assessment and management in subsea structures or equipment. At present, almost all steel pipelines are sensitive to corrosion in harsh working environments, particularly in salty water and sulphur ingress media. Nowadays, the most commonly practiced solution for a damaged steel pipe is to entirely remove the pipe, to remove only a localized damaged section and then replace it with a new one, or to cover it with a steel patch through welding, respectively. Numerous literatures have shown that fiber-reinforced polymer-based composites can be effectively used for steel pipe repairs. Considerable research has also been carried out on the repair of corroded and gouged pipes incorporated with hybrid natural fiber-reinforced composite wraps. Currently, further research in the field should focus on enhanced use of the lesser and highly explored hybrid-biocomposite material for the development in corrosion prevention. A hybrid-biocomposite material from renewable resource based derivatives is cost-effective, abundantly available, biodegradable, and an environmentally benign alternative for corrosion prevention. The aim of this article is to provide a comprehensive review and to bridge the gap by developing a new hybrid-biocomposite with superhydrophobic surfaces.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2006년도 제47회 학술심포지움 및 추계국제학술대회
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• pp.67.2-67.2
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• 2006

• 생태와환경
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• 제53권3호
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• pp.275-285
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• 2020

한강수계 상천천에서 한강납줄개 Rhodeus pseudosericeus와 떡납줄갱이 R. notatus의 잡종으로 추정되는 2개체를 채집하였다. 자연잡종 개체의 체색은 황갈색으로 한강납줄개와 떡납줄갱이의 중간적인 특성을 나타냈지만, 전반적으로 떡납줄갱이의 특징이 두드러졌다. 계수 및 계측형질에서 등지느러미 기조수, 뒷지느러미 기조수, 종렬비늘 수의 3가지 형질은 hybrid index (HI) 값이 0으로 나타나 떡납줄갱이의 형질을 따랐다. 체장에 대한 등지느러미 기점 거리 (HI=74.6), 뒷지느러미 기점 거리 (HI=75.3), 배지느러미 기점 거리 (HI =77.6)는 한강납줄개의 형질을 따르는 것으로 나타났다. 새파수(HI=55.3), 체장에 대한 체고(HI=67.9), 두장에 대한 문장(HI=43.4), 양안간격(HI=44.8)의 4가지 형질은 한강납줄개와 떡납줄갱이의 중간형질을 나타내는 것으로 나타났다. 나머지 14가지 형질은 0과 100 사이를 벗어나 잡종개체만의 고유한 특성을 나타냈다. Recombination activating gene 1 (RAG1) 분석결과 잡종개체는 부모종의 유전자가 중복되어 나타나 자연잡종으로 판별되었으며, cytochrome b gene (COB)를 분석한 결과 한 개체는 한강납줄개를 모계로, 또 다른 한 개체는 떡납줄갱이가 모계로 나타났다.

• Elastomers and Composites
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• 제55권1호
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• pp.59-66
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• 2020

Herein, we investigated the thermal conductivity and thermal stability of natural rubber composite systems containing hybrid fillers of boron nitride (BN) and aluminum nitride (AlN). In the hybrid system, the bimodal distribution of polygonal AlN and planar BN particles provided excellent filler-packing efficiency and desired energy path for phonon transfer, resulting in high thermal conductivity of 1.29 W/mK, which could not be achieved by single filler composites. Further, polyethylene glycol (PEG) was compounded with a commonly used naphthenic oil, which substantially increased thermal conductivity to 3.51 W/mK with an excellent thermal stability due to facilitated energy transfer across the filler-filler interface. The resulting PEG-incorporated hybrid composite showed a high thermal degradation temperature (T₂) of 290℃, a low coefficient of thermal expansion of 26.4 ppm/℃, and a low thermal distortion parameter of 7.53 m/K, which is well over the naphthenic oil compound. Finally, using the Fourier's law of conduction, we suggested a modeling methodology to evaluate the cooling performance in thermal management system.