• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제37회 추계학술대회논문집
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• pp.898-903
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• 2011

위성발사체 액체추진기관 구성품은 발사체의 발사 준비 및 비행을 위해 다양한 작동 mode 및 다양한 환경에서 설계된 성능을 보장하여야 한다. 설계 요건을 충족하는 개발이 이루어졌는지 그리고 개발, 인증, 수락, 조립, 발사 전 시험, 발사 및 비행운용 등의 모든 개발/운용 단계에서 발생 가능한 환경에서 정상작동을 보장하는지를 확인하는 일련의 시험을 통과하여야 실제 목표 궤도에 위성을 투입하기위한 발사체에 장착이 가능하다. 이러한 시험들에 대한 요건들은 이미 발사체 선진국에서는 수십 년의 경험을 바탕으로 그 기준을 마련하고 있다. 현재 한국형발사체 개발을 추진 중인 한국에서도 지난 10여 년간의 액체추진기관을 이용한 발사체 개발에 대한 연구/개발이 있어왔으며, 그 간의 경험을 바탕으로 국내 실정에 맞는 액체추진기관 구성품에 대한 시험요건 구축이 필요하다. 본 논문에서는 국내에서 설정 가능한 액체추진기관 구성품 시험요건에 대한 기준을 고찰하였다.

• 한국의상디자인학회지
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• 제4권3호
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• pp.65-73
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• 2002

The purpose of this study was to prepare lesson plans, study aids and multimedia learning materials for the clothing units in TechnologyㆍHome economics of the 7th national curricula. It's also meant to utilize these materials in instruction in order to provide students with more direct and practical learning experience and make them capable of leading a successful life in the 21st century. 1. The teaching plans were mapped out for the clothing units in TechnologyㆍHome economics class for middle school grade 2, which were all covered by eight textbooks: clothing and life(the function of clothes, my attire, wearing a suit, and wearing Korean traditional dress), the preparation of garments(the type of fiber, understanding of stuff, and preparing garments), and cloth care and storage (washing, storage, alteration and recycling). 2. The lesson plans included information on the name of units, period, learning objectives, teaching environment, materials, learning content, introduction, development, remarks, topping off, announcement for next session, and related Web sites. 3. To raise the effect of education, study aids were developed to be appropriate for the units. The lesson plans and study aids for the clothing part of TechnologyㆍHome economics class for middle school grade 2 would serve to help students build the right clothing habits, and are expected to serve as good teaching materials.

• 한국가구학회지
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• 제24권1호
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• pp.33-41
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• 2013

As professional postnatal care systems have been rapidly supplied, there is sharp increase of postnatal care centers without legal regulations for a mother and a infant. For the quick recovery of mothers, newborn infants that have weaker immune systems are being managed in group in the postnatal care centers. Recently, the attention of the postnatal care centers has been growing because the problem of pneumonia which led to result in a casuality in a infant unit was happen. So, this research analyzed the indoor environment of infant unit through measuring formaldehyde, carbon dioxide, intensity of illumination. As a result of the data, infant units showed higher concentration of formaldehyde and carbon dioxide than Indoor Air Quality Control Law. Moreover, infant units was measured higher intensity of illumination than the range of optimum illumination for infants.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권9호
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• pp.4123-4144
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• 2016

Vehicular Ad Hoc Networks (VANETs) utilize radio propagation models (RPMs) to predict path loss in vehicular environment. Modern urban vehicular environment contains road infrastructure units that include road tunnels, straight roads, curved roads flyovers and underpasses. Different RPMs were proposed in the past to predict path loss, but modern road infrastructure units especially flyovers and underpasses are neglected previously. Most of the existing RPMs are computationally complex and ignore some of the critical features such as impact of infrastructure units on the signal propagation and the effect of both static and moving radio obstacles on signal attenuation. Therefore, the existing RPMs are incapable of predicting path loss in flyovers and underpass accurately. This paper proposes an RPM to predict path loss for vehicular communication on flyovers and inside underpasses that considers both the static and moving radio obstacles while requiring only marginal overhead. The proposed RPM is validated based upon the field measurements in 5 GHz frequency band. A close agreement is found between the measured and predicted values of path loss.

• 한국환경교육학회지:환경교육
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• 제20권2호
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• pp.16-24
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• 2007

The purpose of this study is to understand how the unit objectives and contents associated with environment are reflected on the 6 kinds of chemistry- I textbooks in the 7th curriculum and to present how to deal with the environmental education in chemistry- I. The results of this study are as follows. First, units associated with environment account for an average of 43.7% on chemistry- I in 7th curriculum. Second, contents of units related to environmental education on chemistry- I in 7th curriculum are environmental pollution(17.8%), environmental preservation and environmental pollution prevention(15.9%), environmental hygiene(12.2%), and any other things, Environmental pollution takes up a considerable part of environmental education. Third, the results for analyzing the objectives of chemistry- I in 7th curriculum show that Information Knowledge Awareness(34.0%) and Skill (29.9%) take up most parts. Fourth, Orientation (I) as analysis standard for objective of the units related to environmental education accounts for 10.2% of the total. It is clear that environmental education is carried out from STS point of view. In conclusion, environmental education in Chemistry- I focuses on fostering students' ability to apply the fundamental notion of chemistry to real life associated with environments. Therefore, it is necessary that environmental education in Chemistry- I should include value, attitude and participation and that improve students' ability to approach the environmental problem comprehensively.

• Human Ecology Research
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• 제61권3호
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• pp.375-387
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• 2023

In research on housing welfare policy, there has been little interest in middle-aged households compared with young or elderly households. The purpose of this study was to explore influences on the housing satisfaction of middle-aged renter households using microdata from the Korea Housing Survey 2021. A statistical analysis of data was performed on a total of 2,709,152 middle-aged (aged between 40 and 64 years) Jeonse (lumpsum housing lease) renters and monthly renters with deposits, living in private rental housing units. The major findings were as follows. Firstly, there were significant differences in housing unit satisfaction and residential environment satisfaction among renter groups by age and rental type. Early-middle-aged Jeonse renters displayed the highest satisfaction with both housing units and the residential environment, while semielderly monthly renters with deposits displayed the lowest satisfaction. Secondly, living in aged structures or in apartment units exerted the strongest influences on housing satisfaction, which implies the need for residential area regeneration programs that consider the situation of rental households. Thirdly, living in Incheon and Gyeonggi-do was found to have a negative influence on housing satisfaction. Fourthly, upward filtering on tenure types or lease renewal of the current house did not necessarily have a positive influence on the housing satisfaction of middle-aged renters. Based on the findings, suggestions were made to improve the housing situation of middle-aged renter households.

• 한국산림과학회지
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• 제106권3호
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• pp.275-287
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• 2017

본 연구는 두타산 일대 산림식생구조를 밝히고, 식생유형분류와 입지환경인자와의 상관관계 파악을 목적으로 수행되었다. 2016년 6월부터 10월까지 Z-M학파의 식물사회학적인 방법에 의해 식생조사를 수행하여 총 46개소의 식생자료를 획득하였고, 이 자료를 토대로 식생분류를 실시하였다. 그 결과, 최상위 수준에서 신갈나무군락군으로 분류되었으며, 신갈나무군락군은 철쭉군락과 거제수나무군락의 2개 군락으로 분류되었다. 철쭉군락은 동자꽃군과 철쭉전형군 2개의 군으로 세분되었고 동자꽃군은 박새소군과 동자꽃전형소군 2개의 소군으로 세분되었다. 거제수나무군락은 들메나무군과 박달나무군 2개 군으로 세분되었다. 들메나무군은 병꽃나무소군과 승마소군 2개 소군으로 세분되었다. 두타산 일대 산림식생은 총 6개의 식생단위, 14개의 종군단위, 2쌍의 대별종군으로 분류되었다. 수관층위구조의 분석결과, 식생단위별로 임관의 계층이 서로 겹치지 않는 단조로운 구조인 박새소군(식생단위 1), 동자꽃전형소군(식생단위 2), 병꽃나무소군(식생단위 4)과 겹치는 복잡한 구조인 철쭉전형군(식생단위 3) 승마소군(식생단위 5), 박달나무군(식생단위 6)이 나타났다. 승마소군(식생단위 5)의 수직적 계층구조가 가장 발달하였으며, 박달나무군(식생단위 6)은 초본층 식피율이 가장 낮았다. 일치법에 의한 식생단위와 환경요인과의 상관관계를 보면, 해발 1,100 m, 사면 중부, 경사 $20^{\circ}$, 암석노출도 20%, 교목층 DBH 30 cm를 기준으로 철쭉군락(식생단위 1~3)과 거제수나무군락(식생단위 4~6)이 분류되었다. CCA 분석 결과 철쭉군락(식생단위 1~3)은 해발, 지형과 정의 상관관계, 거제수나무군락(식생단위 4~6)은 부의 상관관계 분포경향이 나타났다.

• KIEAE Journal
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• 제9권3호
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• pp.47-59
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• 2009

In Korea has been supplied a large quantities of apartments since 1970s. The deteriorated middle-rise apartments of 1970s' have been rebuilt. It isn't lucrative to reconstruct the high-rise Apartment estates of the early 1990s' new towns in the capital area. Therefore the sustainable regeneration strategies of them have to be found. This research have been focused on the social and economical changes based on demography and the turning of technology and paradigm, the cities competitiveness compared with 2nd era new towns, physical deterioration of themselves. In these aspects, high-rise apartment estates in the 1st new towns face to 10 challenges such as an aging society, a multicultural society, U-city, an environmentally-friendly situation, the cities competitiveness of social, conomical and physical environment, the declining of estates, buildings and units. This study analyzed problems of 1st new town apartment estates and suggested regeneration tasks in accordence with those problems. The tasks are as follows. To accommodate the 1st new town apartment estates to social changes, they need to have a variety of community facilities and units, an opportunity of esidents participation. to establish a self-sufficient economy, a community usiness has to be vitalized and an ecological environment, an infrastructure of u-city and an improvement of physical environment obtained.

• 한국산림과학회지
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• 제89권4호
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• pp.470-479
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• 2000

광주광역시(光州廣域市)의 대표적인 도시림(都市林)인 무등산(無等山)에 발달하고 있는 산림식생(山林植生)의 보전(保全)과 관리(管理)를 목적으로 식물사회학적(植物社會學的)인 방법에 의해 그 관리단위(管理單位)가 구분되고 그것의 공간적(空間的) 분포(分布)가 정밀(精密)하게 지도화(地圖化)되었다. 이 지역의 산림식생관리단위(山林植生管理單位)는 상위(上位) 21개(個) 단위(單位), 하위(下位) 10개(個) 단위(單位) 그리고 최종하위(最終下位) 9개(個) 단위(單位)로 구분되었으며, 총(總) 31개의 관리구성(管理區城)이 결정되었다. 정밀식생도(情密植生圖) 작성면적은 2,779.5ha이며, 그 중 자연식생(自然植生)이 78.9%인 2,192.0ha로 대부분을 차지하고 있었으며, 인공식생(人工植生)과 무립목지(無立木地)가 각각 5.7%인 159.1ha, 15.5%인 428.4ha로 나타났다. 자연림요소율(自然林要素率)은 타 지역의 도시림에 비교하여 볼 때 아주 높은 93.2%로 나타났다.

• 분석과학
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• 제8권4호
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• pp.799-806
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• 1995

In industrial field, a large volume of regenerants (acid and caustic soda) and their washing effluents are regularly disposed off from the water demineralization plant during regeneration of the ion-exchanger units. Of these waste effluents, a part of the wash water discharged from the single bed Anion and Mixed Bed units can be utilized at a certain stage of their washing cycles when its conductivity is fallen down and becomes considerably less than that of the input raw water. The main aim of this specific waste effluent utilization is to dilute the TDS concentration of the input raw water (fed into the single bed ion-exchanger units) by blending. The achievement is the increase of the longevity of the production cycles of the I.E. units along with the improvement of the production quality and decrease of the regeneration frequencies. As a result, regenerant consumption would be saved because of the reduction of ionic load in feed water which will ultimately reduce the water purification cost. At the same time, the environment pollution will also be protected to a considerable extent. This operational measure is quite effective and useful specially where high TDS water is demineralized only by single bed ion-exchangers. In such case, the water treatment plant is very often found to suffer from both production quality and quantity in addition to carrying out of random and restless regenerations. Proper reuses of the aforesaid wash water effluents of the Anion and MB units excellently minimizes the difficulties experienced in practice. This paper contains the utilities and techniques of reuses of the different kinds of waste effluents of the industrial water treatment plant in addition to the specific reuses of the post-regeneration wash waters of the Anion and MB ion-exchanger units.