• Ocean Science Journal
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• 제42권3호
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• pp.165-170
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• 2007

The structure of the nematodes communities has been studied in the sediments on two sites located outside and under the layer of Ahnfeltia tobuchiensis (Kanno and Matsubara 1932; Makijenko 1970). Bottom sediments at the stations were represented by sands with a different degree of silting. Specific structure of nematodes at the stations was significantly different under the similar environmental conditions (water depth, dissolved oxygen saturation, salinity, temperature of the bottom layer and organic carbon content inside of the sediment). Nematodes dominated (75.7 %) in meiobenthos community under the layer of A. tobuchiensis where concentration of silt particles was 12 %. Representatives of the family Comesomatidae were dominant. Low index of species diversity and high Simpson domination index were detected in this community. Under a layer of A. tobuchiensis with the thickness of 30 cm concentration of the silt particles was 5.39 %; nematodes density was low and made 32.1 % of the general density of meiobenthos. Species of the families Xyalidae and Monoposthiidae were dominant. Outside of A. tobuchiensis, field percentage of silt particles was minimal (3.1 %) and representatives of families Cyatholaimidae and Axonolaimidae dominated. The specific structure of nematodes in this type of the ground is characterized by high index of species diversity and low level of domination.

• 한국농촌생활과학회지
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• 제5권1호
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• pp.57-66
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• 1994

The purpose of the study was to analyze the family structure in rural Korea systematically and comprehensively according to the broad concept. The data was collected from 810 rural households by interview method with questionnaire. For the analysis, family structure was divided into aspects of static structure and dynamic structure. The static structure was constructed by two components of demographic structure and typological structure. The dynamic structure was also constructed by three components of decision making structure, role structure, and dynamic relationship structure of family members. In demographic structure, family size was 4.1 persons, families, with more female were 35.2%, and families with elder husband than wife were 82.5%, In the typological structure, nuclear family type with two-generation was predominant. In dynamic structure, role structure was autonomic type while conjugal power structure was compounded type with autonomic, syncratic, and husband-dominant type.

• 한국연소학회지
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• 제4권2호
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• pp.97-108
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• 1999

This numerical study was to investigate the effect of $CO_2$ addition on the structures and NOx formation characteristics in $CH_4$ counterflow diffusion flame. The importance of radiation effect was identified and $CO_2$ addition effect was investigated in terms of thermal and chemical reaction effect. Also the causes of NOx reduction were clarified by separation method of each formation mechanisms. The results were as follows : The radiation effect was intensified by $CO_2$ addition. Thermal effect mainly contributed to the changes in flame structure and the amount of NO formation but the chemical reaction effect also cannot be neglected. The reduction of thermal NO was dominant with respect to reduction rate, but that of prompt NO was dominant with respect to total amount.

• 한국패류학회지
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• 제7권1호
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• pp.49-57
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• 1991

A study on the distribution and community structure of the benthic macroinvertebrates on the intertidal zones of Gapa and Mara islets were carried out from March to June 1991. The macroinvertebrates collected and identified were composed of 7 phyla, 14 classes, 29 orders, 68 families and 132 speies in Gapa islet and of 7 phyla, 12 classes, 23 orders, 49 familis and 90 species in Maara islet. The first and second dominant species and the community dominance indices of the upper tidal zones of Gapa and Mara islets were Nodilittorina exigua, Pollicipes mitella and 79.01, 69.77 respectively. However, the dominant species of the middle and lower intertidal zones of the two islets were not identities and different among the tidal zones.

• 한국패류학회지
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• 제7권1호
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• pp.58-65
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• 1991

A study on the distribution and community structure of the benthic molluscan shells of the southern coastral area in Cheju Island was carried out from August 1990 to July 1991. The benthic molluscan shells collected and identified from 8 stations were composed of 3 classes, 7 orders, 22 families and 59 species. The number of appearance species from station 1 to station 8 were 22, 35, 32, 26, 28, 24, 32 and 31 species respectively. the first dominant species of the upper intertidal zone of the 8 stations were Nodilittorina exigua, those of the middle zones were Monodonta neritoides from st.1 to St.5, but the second dominant species were not uniftom at ach station.

• ALGAE
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• 제18권4호
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• pp.301-309
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• 2003

Community structure and vertical distribution of benthic marine algae were investigated in the intertidal and subtidal rocky shore of Samyang, Jejudo Island. The total number of 62 algal species composed of 6 Cyanophyta, 6 Chlorophyta, 19 Phaeophyta, and 31 Rhodophyta were observed. The dominant species were melobesioidean algae, Sargassum thunbergii, Hizikia fusiformis, and Ulva pertusa in the intertidal zone and melobesioidean algae, Ulva pertusa, Corallina spp., and Undaria pinnatifida in the subtidal zone. The vertical algal distribution was represented by the melobesioidean algae in the whole rocky shore, Caulacanthus ustulatus in the upper intertidal zone, Sargassum thunbergii and Hizikia fusiformis in the middle and lower zone, Ulva pertusa in the lower zone and Ulva pertusa, Corallina spp., and Undaria prinnatifida in the subtidal zone. The composition of dominant species and pattern of the vertical distribution of algae in the present study were significantly different from the previous reports. Especially, distribution of crustose coralline algae was significantly extended.

• Wind and Structures
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• 제7권5호
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• pp.333-344
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• 2004

This paper illustrates application of the proper orthogonal decomposition (POD) and the autoregressive (AR) model to simulate large wind pressures due to gusts on a low-rise building. In the POD analysis, the covariance of the ensemble of large wind pressures is employed to calculate the principal modes and coordinates. The POD principal coordinates are modeled using the AR process, and the fitted AR models are employed to generate the principal coordinates. The generated principal coordinates are then used to simulate large wind pressures. The results show that the structure characterizing large wind pressures is well represented by the dominant eigenmodes (up to the first fifteen eigenmodes). Also, wind pressures with large peak values are simulated very well using the dominant eigenmodes along with the principal coordinates generated by the AR models.

• 대한기계학회논문집B
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• 제33권8호
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• pp.589-595
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• 2009

The instability wave formed near nozzle region grows to vortex with large scale in downstream region of spray. It plays an important role in the fuel-air mixing, combustion process and engine exhaust emissions in direct injection diesel engine. The objective of this study is to analyze effect of variant parameters (injection pressure, ambient gas density, etc.) and fuel properties on spray instability near nozzle region. Spray structure near nozzle region was investigated using a magnification photograph. A pulsed Nd-YAG laser was used as a light source, and image was taken by CCD camera. The following conclusions are drawn from this experimental analysis. In low ambient density, the effect of fuel properties on spray instability near nozzle region is dominant. In high ambient density, the effect of ambient gas on spray instability near nozzle region is dominant. High jet velocity has strong influence on spray instability.

• 경영정보학연구
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• 제18권1호
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• pp.177-197
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• 2016

현대 기업에서의 정보기술 아웃소싱(Information Technology Outsourcing: ITO)은 비즈니스 프로세스 및 정보기술의 고도화와 함께 수행영역과 적용기술 등의 다양한 측면에서 진화를 거듭하고 있다. 특히, ITO 프로젝트의 수행과정에서 고객과 공급업체들 간의 관계구조는 과거 단일 공급업체가 주도하는 단순한 형태를 벗어나 기술적 전문성과 관리기법을 겸비한 복수의 공급업체가 참여하는 형태(Multi-vendor Outsourcing: MVO)의 비중이 높아지고 있다. 본 연구에서는 고객과 공급업체간 관계구조가 ITO 수행 시 수반되는 거래비용의 구조와 크기를 변화시킴으로써, 결과적으로 ITO 성과에 영향을 미치게 된다는 전제를 바탕으로, 다음과 같은 질문에 답하고자 한다. 고객과 복수의 공급업체들 간에 맺어지는 관계구조의 형태가 특정 유형의 ITO 성과에 영향을 미치는가? 본 연구는 거래비용 이론(Transaction Cost Theory)을 기반으로, 고객과 공급업체들 간에 맺어지는 관계구조의 유형을 두 가지로 나누어 제시하였다. 아울러, ITO 수행과정에서의 거래비용을 살펴봄으로써 각각의 관계유형에 상대적으로 부합하는 ITO 성과유형을 제시하는 내용을 가설화하였다. 제시된 가설에 관한 검증은 ITO를 수행하는 국내 246개 기업으로부터 수집된 자료를 바탕으로 진행되었다. 분석결과를 통해, 특정 관계 구조 유형은 그에 부합하는 형태의 ITO 성과에 더 많은 영향을 미치고 있는 것을 확인 하였다. 본 연구는 ITO 프로젝트의 수행 과정에서 IT 실무자들이 아웃소싱 공급업체들과의 관계구조를 설정하고 운용하는 데 있어 주요한 참조자료로 활용될 수 있을 것이다.

• 한국환경복원기술학회지
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• 제13권3호
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• pp.84-93
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• 2010

This study was carried out to analyze the vegetation properties, soil characteristics and ordination of Leontice microrhyncha population in South Korea. The Leontice microrhyncha population was classified into Quercus mongolica dominant population, Morus bombycis dominant population, Fraxinus mandshurica population and Leontice microrhyncha typical dominant. The Leontice microrhyncha population was located at an elevation of 633m to 1,336m in Korea. In the study sites, soil organic matter, total nitrogen, available phosphate, exchangeable potassium, exchangeable calcium, exchangeable magnesium, cation exchange capacity and soil pH were 8.40~10.58%, 0.42~0.61%, 14.15~25.07mg/kg, 0.44~0.59cmol$^+$/kg, 2.35~6.33cmol$^+$/kg, 0.35~0.98cmol$^+$/kg, 26.04~33.48cmol$^+$/kg and 4.69~5.32 respectively. Morus bombycis dominant population was found in the low elevation and gentle sloped area that has high percentage of phosphoric acid and less percentage of total nitrogen, exchangeable calcium, exchangeable magnesium than other dominant population. Fraxinus mandshurica dominant population and Leontice microrhyncha typical population were found in the comparatively high elevation area that has low percentage of phosphoric acid and high percentage of total nitrogen, exchangeable calcium, exchangeable magnesium. Quercus mongolica dominant population was found in the medium elevation area that has medium percentage of total nitrogen, exchangeable calcium, exchangeable magnesium.