• 한국연소학회:학술대회논문집
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• 한국연소학회 2005년도 제31회 KOSCO SYMPOSIUM 논문집
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• pp.156-161
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• 2005

Two and Three dimensional numerical simulations have been carried out to understand the combustion characteristics of LNG-fueled gas turbine combustor for power generation. Focus of the study was given to the influences of different fuel composition of imported and domestic natural gases with the flow conditions selected from the gas turbine operation data. Reacting flow characteristics of the swirl stabilized natural gas combustor were understood from the comparison of the two-dimensional and three-dimensional results. The thermal influences of different natural gases were very small and the fuel composition and flow rate were considered to be tuned well.

• 미생물학회지
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• 제23권2호
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• pp.157-165
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• 1985

Bacterial identification was performed with morphological, physiological and biochemical tests to the isolates from the mudflat of 30cm depth sampled in Nakdong river estuary in March and June, 1985. Flavobacterium and Cnterobacteriaceae were regarded as dominants. Pseudomonas, Bacillus, Micrococcus, Vibrio, Aerococcus, Aerononas, Acinetobacter and Staphylococcus were founded in various depth. Vertical composition of bacterial genera in March was more diversiform than that of June. Character analysis was carried out with the calculation of similarity index (S). At a level of 85% similarity, the isolates were clustered into 5 groups and ungrouped 2 strains. Classifying groups of bacterial strains with determination schemes and groups from similarity index were in good agreement.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 동계학술발표대회 논문집
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• pp.181-185
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• 2008

The new concept for liquefaction of natural gas has been designed and simulated in this paper. Conventional liquefaction cycles are usually composed with Joule-Thomson valves at lower temperature refrigerant cycle. The new concept of natural gas liquefaction is discussed. The main difference with conventional liquefaction process is the presence of the turbine at low temperature of MR (mixed refrigerant) cycle. The turbine acts as expander but also as an energy generator. This generated energy is provided to the compressor which consumes energy to pressurize refrigerants. The composition of the mixed refrigerant is investigated in this study. Components of the refrigerant are methane, propane and nitrogen. Composition for new process is traced with Aspen HYSYS software. LNG heat exchangers are analyzed for the new process. Heating and cooling curves in heat exchangers were also analyzed.

• 역사민속학
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• 제57호
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• pp.197-228
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• 2019

본 논문은 기존 연구에서 전통마을의 공간구성을 분류한 연구들을 일별해 보고, 그것들을 보완하여 새롭게 전통마을의 공간구성과 속성을 정리하였으며, 다음으로는 새롭게 정리된 공간구성 분류에 맞추어 기존연구를 활용하되 필자가 강조하고자 하는 사항을 보안하여 한국 전통마을의 공간 구성을 재론한 것이다. 먼저 전통마을의 공간구성으로 ①자연공간 ②주거공간 ③생업공간 ④이동공간 ⑤경계공간 ⑥놀이공간 ⑦제의공간의 7가지를 추출하였다. 그리고 그것을 기본성격에 맞추어, ①마을입지의 기본 공간 : 자연공간 ②자연공간 하에서 요청되는 필수 생존공간 : 주거공간 및 생업공간 ③마을 구성원 상호소통망에서 파생된 관계공간 : 이동공간 및 경계공간 ④장(場)의 개념으로 확산되는 가변공간: 놀이공간 및 제의공간의 4개 요소로 다시 제시하여 서술하였다. 사람이 만든 공간은 사람들의 삶을 담는 그릇이다. 그 그릇이 편리하고 쓰임새 있는 그릇이 되기 위해서는 삶의 틀에 맞추어진 것이어야 한다. 우리의 전통마을의 공간구성은 구성원들의 자연관·생활양식·세계관이라는 삶의 틀에 잘 구현되어 있었다. 자연관은 마을 공간구성 전체에 작용하지만 특히 자연공간에 잘 반영되어 있다. 생활양식은 주거공간·생업공간·이동공간·놀이공간에, 그리고 세계관은 경계공간·제의공간에 특색있게 반영되어 있다. 이러한 모든 것들을 유기적으로 작동시키기 위하여 공동체적 규약이 있었다.

• Kyungpook Mathematical Journal
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• 제49권4호
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• pp.683-689
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• 2009

We investigate the gaps among classes of weakly hyponormal composition operators induced by Embry characterization for the subnormality. The relationship between subnormality and weak hyponormality will be discussed in a version of composition operator induced by a non-singular measurable transformation.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1999년도 한국생물과학협회 학술발표대회
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• pp.238.2-238
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• 1999

No Abstract, See Full Text

• Macromolecular Research
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• 제15권1호
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• pp.65-73
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• 2007

Chitosan, fibroin, and hydroxyapatite are natural biopolymers and bioceramics that are biocompatible, biodegradable, and resorb able for biomedical applications. The highly porous, chitosan-based, bioceramic hybrid composite, chitosanlfibroin-hydroxyapatite composite, was prepared by a novel method using thermally induced phase separation. The composite had a porosity of more than 94% and exhibited two continuous and different morphologies: an irregularly isotropic pore structure on the surface and a regularly anisotropic multilayered structure in the interior. In addition, the composite was composed of an interconnected open pore structure with a pore size below a few hundred microns. The chemical composition, pore morphology, microstructure, fluid absorptivity, protein permeability, and mechanical strength were investigated according to the composition rate of bioceramics to biopolymers for use in tissue engineering. The incorporation of hydroxyapatite improved the fluid absorptivity, protein permeability, and tenacity of the composite while maintaining high porosity and a suitable microstructure.

• ALGAE
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• 제27권3호
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• pp.189-196
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• 2012

Twelve morphological characters and the biochemical composition of Undaria pinnatifida f. distans sporophytes growing on the rocky shores of Jindo and Wando and on cultivation ropes in Kijang were measured to determine whether each population could be characterized by morphological features and biochemical composition. The goal of this study was to compare phenotypic variations between populations as they relate to environmental conditions. The sporophytes of the Kijang population were two times longer and 19 times heavier than those at Jindo. Sporophylls of the Jindo U. pinnatifida population were significantly smaller in length, width, frill number, and weight than those at Wando and Kijang. Kijang Undaria plants showed the highest contents of total protein, crude fiber, total amino acids, the amount of essential amino acids, the proportion of total unsaturated fatty acids, and eicosapentaenoic acid. However, the Jindo population showed the greatest content of carbohydrates, lipids, and minerals (Zn and Ca) of the three U. pinnatifida populations. In particular, Zn content of Jindo plants was 30 times greater than that of Kijang plants. Thus, the proximate composition, mineral composition, amino acids, and fatty acids of Undaria pinnatifida plants were distinguishable among the three representative Undaria populations evaluated. These results suggest that morphological and biochemical differences of the three U. pinnatifida populations can be attributed to differences in environmental conditions of their habitats.

• 정보과학회 컴퓨팅의 실제 논문지
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• 제23권12호
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• pp.698-702
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• 2017

자연 언어 처리(Natural Language Processing) 분야에 심층 신경망(Deep Neural Network)이 소개된 이후, 단어, 문장 등의 의미를 나타내기 위한 분산 표상인 임베딩(Embedding)을 학습하기 위한 연구가 활발히 진행되고 있다. 임베딩 학습을 위한 방법으로는 크게 문맥 기반의 텍스트 모델링 방법과, 기학습된 임베딩을 결합하여 더 긴 텍스트의 분산 표상을 계산하고자 하는 결합 기반의 텍스트 모델링 방법이 있다. 하지만, 기존 결합 기반의 텍스트 모델링 방법은 최적 결합 단위에 대한 고찰 없이 단어를 이용하여 연구되어 왔다. 본 연구에서는 비교 실험을 통해 문서 임베딩 생성에 적합한 결합 기법과 최적 결합 단위에 대해 알아본다. 또한, 새로운 결합 방법인 담화 분석 기반의 결합 방식을 제안하고 실험을 통해 기존의 순차적 결합 기반 신경망 모델 대비 우수성을 보인다.

• Elastomers and Composites
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• 제57권4호
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• pp.188-196
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• 2022

Styrene-butadiene rubber(SBR) is a copolymer of styrene and butadiene. It is composed of 1,2-unit, 1,4-unit, and styrene, and its properties are dependent on its microstructure. In general, rubber composites contain a single rubber or a blended rubber. Similarly, SBR is used by mixing with natural rubber(NR) and butadiene rubber(BR). The composition of a rubber article affects its physical and chemical properties. Herein, an analytical method for determining the microstructure of SBR using via pyrolysis is introduced. Pyrolysis-gas chromatography/mass spectrometry is widely used to analyze the microstructure of polymeric materials. The microstructure of SBR can be determined by analyzing the principal pyrolysis products formed from SBR, such as 4-vinylcyclohexene, styrene, 2-phenylpropene, 3-phenylcyclopentene, and 4-phenylcyclohexene. An analytical method for determining the composition of SBR/NR, SBR/BR, and SBR/NR/BR blends via pyrolysis is introduced. The composition of blended rubber can be determined by analyzing the principal pyrolysis products formed from each rubber component.