• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.64-65
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• 2014

Recently freeform buildings which are free from simple shape are implemented depending on improvement of construction method. However, freeform buildings are spent more time and cost to materialize than typical form. Because molds for production of freeform shape cannot be reused. For these reasons, low productivity, delay of construction schedule and budget overflow are occurred. Thus, technology of molds need to be developed for manufacturing of freeform concrete segments. The objective of this study is manufacturing of freeform concrete segments using rod type mold. This technology can implement not only application to various shape but also mass production. Thus, problems of construction period, productivity and cost can be solved. After this study, productivity analysis should be continued through the field application.

• 한국농림기상학회지
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• 제1권1호
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• pp.60-71
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• 1999

The micrometeorological tower flux network is the cornerstone of the global terrestrial vegetation monitoring. The eddy covariance technique used for tower fluxes is derived from the conservation of mass and is most applicable for steady-state conditions over flat, extended, and uniform vegetation. This technique allows us to obtain surface fluxes of energy budget components, greenhouse and trace gases, and other pollutants. The quality-controlled flux data are invaluable to validate various models with temporal scales ranging from minutes to years and spatial scales ranging from a few meters to hundreds of kilometers. In this paper, we review the theoretical background of this important eddy covariance technique, examine the measurement criteria and corrections, and finally suggest some measurement strategies that may facilitate coordinated flux measurements among different disciplines and provide a strong infrastructure for the global flux network.

• 시스템엔지니어링학술지
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• 제1권1호
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• pp.61-66
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• 2005

In executing the large scale national project, such as development of space launch vehicle, it is most important to guarantee the technological reliability. However the reliability analysis of launch vehicle is different from other mass product goods because of the limitation of budget and number of tests. In this study, the reliability analysis technique of the propulsion system, which is one of the major sub-systems of launch vehicle is illustrated and applied to the liquid rocket engine of KSR-III.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2004년도 한국우주과학회보 제13권2호
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• pp.341-343
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• 2004

In executing the large scale national project, such as development of space launch vehicle, it is most important to guarantee the technological reliability. However the reliability analysis of launch vehicle is different from other mass product goods because of the limitation of budget and number of tests. In this study, the reliability analysis technique of the propulsion system, which is one of the major sub-systems of launch vehicle is illustrated and applied to the liquid rocket engine of KSR-III.

• 한국문헌정보학회지
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• 제16권
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• pp.243-279
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• 1989

Public library effectiveness is determined by a complexity of the internal and external environments of the library. The purpose of this article is to investigate community environments and library resources as determinants of the output measures of the 15 municipal libraries in Seoul and to cope with changes in the environments for the improvement of their performance. This study is based on the hypotheses that the library's output would be proportioned to the size of budget and library collection, and to the relationships between the characteristics of the library and of the community in which the library develops. The variables identified in this .study are population density, family size, institutions (social, cultural, financial and educational), presence of the mass media, size of service area, and economic level of the community. The output measures employed for analysis are: number of professional staff, expenditures, number of books in the collection, number of books added annually, total circulation, number of library visits, circullation per capita, library visits per capita, .and registration as a percentage of population. The recommendation made in this study is the innovation of the 15 libraries in organization.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.135-136
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• 2023

The Vocational Rehabilitation Center Expansion Project, with a budget of 15.3 billion KRW, transformed an existing facility into a more eco-friendly, user-friendly, and publicly accessible space. The project involved expanding the building from a basement and two above-ground floors to a basement and six above-ground floors, addressing the shortage of facilities for people with disabilities while promoting eco-friendliness. Design concepts included eco-friendly MASS, improvements to the existing building, social adaptability, and user-centric evacuation measures. Value Engineering (VE) and technical reviews led to proposals for cost reduction and functionality enhancement. Completed in September 2019, the project, renamed "Se-um Center," now hosts seven disability welfare facilities, serving as a vital infrastructure improving the lives of individuals with disabilities in the local community.

• The Korean Journal of Ecology
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• 제27권4호
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• pp.245-256
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• 2004

Simple Biosphere model 2(SiB2)는 전구기후모형 (global climate model)의 지표면모형으로서 토양-식생-대기 사이의 에너지, 물 및 이산화탄소 교환을 모의한다. 특히 광합성-기공전도 하부모형을 포함하고 있어, 식물군락의 광합성과 기공개폐기작을 근거로 하여 이산화탄소 동화량 및 물의 증산량을 계산한다. 따라서 SiB2 수치실험 결과를 통해, 육상생태계에 있어서의 이산화탄소 순환, 물수지, 그리고 환경과 식물군락간의 상호관계를 분석할 수 있다. 본 종설은 일례로서 개량된 SiB2-Paddy를 이용하여, 다양한 식생 및 토지 이용을 보이는 태국 챠오플라야강 유역의 하천유출량 변화에 관한 연구를 소개한다. 이는 SiB2 수치실험결과가 지표면 식생의 차이에 따른 유출량의 변화를 예측 가능하며, 이를 통하여 육상생태계에 있어서 식생이 갖는 기능적인 측면을 연구하는데 적합한 모형임을 알 수 있었다. 그러나 SiB2모형을 이용하여 더욱 정확도 높은 육상 생태계 모의를 위해서는 토양호흡, 엽면적지수, 식물군락간 경쟁 그리고 뿌리의 분포를 고려한 토양수분 등을 모의할 수 있는 하부모형의 도입이 필요하다.

• 천문학회보
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• 제40권2호
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• pp.42.2-43
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• 2015

Massive stars play a major role in the interstellar energy budget and the shaping of the galactic environment. The water molecule is thought to be a sensitive tracer of physical conditions and dynamics in star-forming regions because of its large abundance variations between hot and cold regions. Herschel/HIFI allows us to observe the multiple rotational transitions of H2O including the ground-state levels, and its isotopologues toward high-mass star-forming regions in different evolutionary stages. Photodissociation regions (PDRs) are also targeted to investigate the distribution of water and its chemistry. We present line profiles and maps of H2O using data from two guaranteed-time key programs "Water In Star-forming regions with Herschel" and "Herschel observations of EXtra-Ordinary Sources". We analyze the temperature and density structures using LTE and non-LTE methods. We also estimate turbulent and expansion velocities, and abundance of water in the inner and outer envelopes using the 1D radiative transfer code. Around high-mass protostars we find H2O abundances of ~10-8-10-9 for the outer envelope and ~10-4-10-5 for the inner envelope, and expansion and turbulent velocities range from 1.0 km s-1 to 2.0 km s-1. The abundances and kinematic parameters of the sources do not show clear trends with evolutionary indicators. The Herschel/HIFI mapping observations of H2O toward the Orion Bar PDR show that H2O emission peaks between the shielded dense gas and the radicals position, in agreement with the theoretical and the observational PDR structure. The derived H2O abundance is ~10-7 and peaks at the depth of AV ~8 mag from the ionization front. Together with the low ortho-to-para ratio of H2O (~1) presented by Choi et al. (2014), our results show that the chemistry of water in the Orion Bar is dominated by photodesorption and photodissociation.

• 한국대기환경학회지
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• 제19권6호
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• pp.647-661
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• 2003

For continuous monitoring of atmospheric visibility in the city of Kwanaju, Korea, a transmissometer system consisting of a transmitter and a receiver was installed at a distance of 1.91 km across the downtown Kwanaju. At the transmitter site an integrating nephelometer and an aethalometer were also installed to measure the scattering and absorption coefficients of the atmosphere, respectively. At the receiver site. an URG PM$_{2.5}$ cyclone sampler and an URG-VAPS (Versatile Air Pollutant Sampler) with three filter packs and two denuders were used to collect both PM$_{2.5}$ and PM$_{10}$ samples at a 2-hour or 12-hour sampling interval for aerosol chemical analysis. Sulfate, organic mass by carbon (OMC), nitrate, elemental carbon (EC) components of fine aerosol were the major contributors to visibility impairment. Diurnal variation of visibility during best-case days showed rapid improvement in the morning hours, while it was delayed until afternoon during the worst-case days. Aerosol mass concentration of each aerosol component for the worst-case was calculated to be 11.2 times larger than the best-case for (NH$_4$)$_2$SO$_4$(NHSO), 19.0 times for NH$_4$NO$_3$ (NHNO), 2.2 times for OMC, respectively. Also result shows that elemental carbon and fine soil (FS) were 3.7 and 2.2 times more than those of best-case. respectively- Sum of total contributions of wet NHSO and NHNO to light extinction was calculated to be 301 Mm$^{-1}$ for the worst-case. However, sum of contributions by dry NHSO and NHNO was calculated to be 123 Mm$^{-1}$ for the best case. Mass extinction efficiencies of fine and coarse particles were calculated to be 5.8$\pm$0.3 $m^2$/g and 1.8$\pm$0.1 $m^2$/g, respectively.ely.

• Journal of the korean society of oceanography
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• 제33권4호
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• pp.157-167
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• 1998

The distribution of particulate organic carbon and nitrogen (POC and PON) and chlorophyll a of particulate organic matter was investigated in the southwestern East Sea in August and October 1995. The upwelled 'cold water mass' with temperature less than 14$^{\circ}$C occurred near the Campo coast in August. At most of the onshore stations, concentrations of POC and PON were high in surface water, rapidly decreased with depth down to 30 m and then remained constant. Differences in their concentrations between surface and bottom waters were larger in August than in October. At the offshore stations, POC and PON were higher in surface than in deep waters though the differences in concentration were small. The highest, vertically integrated inventories of POC, PON and phytoplanktonic carbon in the upper mixed waters of the onshore stations occurred in August. The mixed layers at onshore stations showed relatively high percentages of POC, PON and chlorophyll a in total suspended matter, low ratios of POC to chlorophyll a and high inventories of phytoplanktonic carbon, compared with the values at offshore stations. These phenomena were more obvious in August, when cold water mass developed strongly, than in October. These results indicate that primary production plays a significant role for the budget of particulate organic matter in the upwelled cold water mass of the southwestern East Sea.