• 한국산학기술학회논문지
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• 제18권6호
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• pp.742-752
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• 2017

본 논문은 중공슬래브 교량의 장점을 극대화하여 프라캐스트로 제작된 PSC-I거더의 단순한 조립을 통해 중공슬래브를 형성시키는 교량공법을 제안하고 이를 검증하였다. 하천이나 단지 내 교량과 같이 저형고 거더교가 요구되는 현장에 고가인 강합성 계열의 교량이 적용되어 과도한 공사비가 소요되고 있으며, 다양한 장점을 갖는 중공슬래브 교량이 콘크라트의 현장타설로 인해 중공부에 구조적 균열이 발생하여 그 적용성이 확장되지 못하고 있는 실정이다. 따라서, 본 연구를 통해 새로운 거더공법을 대안으로 제시하고 설계기준에 따른 강도와 응력검토, 제작을 위한 거푸집의 설계, 시공단계별 절차 등 현업적용을 위한 기반기술을 개발하였으며, 조립된 거더가 일체로 거동하도록 각 거더의 횡방향 연결을 위한 다양한 공법을 제시하고 적정성을 검토하였다. 또한, 실물크기의 실험체 거더 2본을 제작하고 시공과정에서의 문제점들을 도출하였으며, 하중재하 실험을 수행하여 거더의 성능과 적용성을 검토하였다. 실험결과, 하중의 편측 재하시 발생한 수직변위 계측을 통해 두 거더가 일체로 거동하는 것을 확인하였으며, 설계하중 내에서 선형탄성 휨 거동을 보이며 예상된 설계 강도를 넘어서는 우수한 성능을 나타내었다.

• 한국가족복지학
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• 제56호
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• pp.69-104
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• 2017

본 연구는 조손가족 손자녀들의 성장과정을 환경적 맥락을 통해 심층적으로 살펴보고자 하는 것이 목적이다. 이러한 목적을 위해 두 명의 조손가족 손자녀를 대상으로 한 심층 면접, 관찰, 기록물 등의 방법을 활용하여 자료를 수집하였으며, 생애사 접근을 통해 분석하였다. 자료 분석은Mandelbaum(1973)이 제시한 삶의 영역, 전환점, 적응을 분석틀로 하였다. 연구결과, 삶의 영역은 '독특한 가족 환경', '클수록 커지는 빈곤', '애써 짓는 미소', '더 예의바르게 정직하게', '혼자가되는 것'이었다. 삶의 전환점은 '부모 없는 아이', '아픈 기억, 왕따', '대학 진학', 삶의 적응은' 의지하고 싶은 사람, 부모', '인복(人福)', '자립심과 규모 있는 경제생활', '성실함과 선천적인 쾌활함'으로 나왔다. 이러한 결과를 토대로 조손가족 손자녀의 건강한 성장을 위한 개입전략과 시사점을 제시하였다.

• 사회경제평론
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• 제31권3호
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• pp.55-92
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• 2018

촛불혁명으로 집권한 문재인 정부는 사람주도경제를 내걸었다. 이러한 목표를 실현하기 위해 과거 보수정부보다 재정지출 증가율을 높이고 복지비중을 늘리겠다고 약속했다. 이러한 정책 방향은 바람직한 것이긴 하지만 적극적 증세 없이 재정수입 이내에서 최대한 지출하겠다는 것이어서 대규모의 복지확대를 바라는 진보진영의 기대에는 한참 못 미치는 것이다. 현재 우리나라가 당면한 구조적 위기를 극복하기 위해서는 더욱 적극적인 재정정책이필요이다. 당분간은 직접세 위주로 소득 상위 가계와 법인, 고액자산 보유자에 대한 증세를 추진하고 임대소득과세가 잘 정착되도록 노력하면서 국가채무의 증가도 용인하는 방식의 적극적 재정정책을 시행하는 것이 바람직할것이다. 이러한 과제가 잘 마무리되면 다음 단계의 복지확대 및 증세로 나아가는 것이 필요하다.

• Human Ecology Research
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• 제57권4호
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• pp.499-512
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• 2019

Korean adolescents have a lower subjective well-being compared to their counterparts in other Organization for Economic Co-operation and Development member countries as well as experience more psychological difficulties than adults. Previous research shows that parenting behavior has a considerable influence on adolescent subjective well-being. Additionally, the personality dimension of self-directedness, the ability to regulate personal behavior to obtain onindividual goals, has a positive influence on subjective well-being. This study analyzed the structural relationship between parenting behavior, self-directedness, and the subjective well-being of Korean adolescents as well as investigated the mediating effect of self-directedness in the relationships between parenting behaviors and the subjective well-being of adolescents. Participants were 325 middle school students in Gwangju, Korea, who completed measures of self-directedness (from the Korean Junior Temperament and Character Inventory), subjective well-being (Well-Being Scale of Adolescents in Korea), and perceived parenting behaviors (My Memories of Upbringing - Short Korean version). Results showed that emotional warmth had a statistically significant direct impact on adolescents' subjective well-being. However, the findings also indicated a statistically significant indirect impact mediated by self-directedness. Rejection and overprotection had a statistically significant indirect effect on adolescents' subjective well-being that was mediated by self-directedness. The results provide information that can be used to develop programs to improve the subjective well-being of adolescents as well as confirm the importance of parenting behavior and self-directedness during adolescence.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2017년도 학술발표회
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• pp.191-191
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• 2017

Floods have become more widespread and frequent among natural disasters and consisted significant losses of lives and properties worldwide. Flood's impacts are threatening socio-economic and people's lives in the Mekong River Basin every year. The objective of this study is to identify the flood hazard areas and inundation depth in the Mekong River Basin. A rainfall-runoff and flood inundation model is necessary to enhance understanding of characteristic of flooding. Rainfall-Runoff-Inundation (RRI) model, a two-dimensional model capable of simulating rainfall-runoff and flood inundation simultaneously, was applied in this study. HydoSHEDS Topographical data, APPRODITE precipitation, MODIS land use, and river cross section were used as input data for the simulation. The Shuffled Complex Evolution (SCE-UA) global optimization method was integrated with RRI model to calibrate the sensitive parameters. In the present study, we selected flood event in 2000 which was considered as 50-year return period flood in term of discharge volume of 500 km3. The simulated results were compared with observed discharge at the stations along the mainstream and inundation map produced by Dartmouth Flood Observatory and Landsat 7. The results indicated good agreement between observed and simulated discharge with NSE = 0.86 at Stung Treng Station. The model predicted inundation extent with success rate SR = 67.50% and modified success rate MSR = 74.53%. In conclusion, the RRI model was successfully used to simulate rainfall runoff and inundation processes in the large scale Mekong River Basin with a good performance. It is recommended to improve the quality of the input data in order to increase the accuracy of the simulation result.

• Safety and Health at Work
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• 제5권4호
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• pp.210-215
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• 2014

Background: The ongoing economic crisis in Greece has affected both stress and quality of life (QoL) at all socioeconomic levels, including professionals in the police force. The aim of this study was to examine perceived stress, job satisfaction, QoL, and their relationships in a sample of police officers in Greece. Methods: A cross-sectional study was conducted during the first trimester of 2011 in 23 police stations in the greater Athens area. A total of 201 police officers agreed to participate (response rate 44.6%). The General Health Questionnaire-28 (GHQ-28) was used to assess general health, and the World Health Organization Quality of Life-BREF Questionnaire and Perceived Stress Scale-14 (PSS-14) questionnaires were used to assess QoL and perceived stress, respectively. Results: The PSS and GHQ subscales and total scores exhibited strong, positive, and significant correlations coefficients (r): 0.52 for somatic disturbances, 0.56 for stress and insomnia, 0.40 for social dysfunction, and 0.37 for depression, yielding an r equal to 0.57 for the total GHQ score. A higher level of perceived stress was related to a lower likelihood of being satisfied with their job; in this regard, male participants and higher ranked officers reported lower job satisfaction. The PSS and GHQ scores were inversely, consistently, and significantly related to almost all of the QoL aspects, explaining up to 34% of their variability. Parenthood had a positive effect on QoL related to physical health, and women reported lower QoL related to psychological health. Conclusion: Higher levels of stress are related to an increased risk of reporting suboptimal job satisfaction and QoL. The magnitude of these associations varied depending on age, gender, and rank, highlighting the need for stress-management training.

• 한국방재학회 논문집
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• 제11권3호
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• pp.237-243
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• 2011

강화되는 방류수 수질기준에 맞추어 하수처리장 개조 방안의 하나로 고농도의 암모니아성 질소를 함유한 반류수를 처리하는 방안이 주장되고 있다. $35^{\circ}C$, $20^{\circ}C$와 $10^{\circ}C$ 조건의 실험실 규모 반응조 운전을 통하여 경제적인 질소 제거 방법인 아질산화 반응 유도하였다. $20^{\circ}C$ 이상의 온도에서는 안정적인 아질산화 반응을 유도 할 수 있었으나, $10^{\circ}C$ 저온 조건에서는 완전 질산화 반응이 유도 되었다. 이는 온도의 영향을 받아 SRT가 길어져 완전 질산화 반응이 유도된 것으로 사료된다. 온도에 따라 아질산화 반응에 요구되는 SRT가 변화하는 것으로 볼 때, 온도와 SRT는 아질산화 반응에 중요한 인자로 판단된다. 또한 $20^{\circ}C$ 이상의 조건에서 암모니아성 질소 제거 반응과 아질산화 반응을 유도하는 것이 유리 한 것으로 나타났다. 본 논문에서 제시한 결과는 아질산화 반응을하수처리장에 적용할 때 중요한 기초 자료로 사용될 수 있을 것이다.

• 한국응용과학기술학회지
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• 제38권4호
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• pp.1010-1019
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• 2021

유전에 매장된 석유는 1차, 2차, 그리고 3차에 걸쳐 회수된다. 3차 회수로 분류된 공법 중 미생물을 이용한 원유 회수증진법은 크게 in-situ와 ex-situ 공법으로 나눌 수 있다. In-situ 공법은 미생물을 저류층에 직접 투입하여 미생물의 대사활동을 통한 원유의 회수를 유도하는 공법이다. 대사물질 중 바이오 계면활성제는 저류층 잔존 유분의 유동화에 큰 역할을 한다. 한편, ex-situ 공법은 외부에서 미생물의 대사물질을 추출하여 저류층에 투입하여 원유를 회수하는 방법이다. 두 가지 공법 모두 친환경적이지만, 보다 경제적인 in-situ 공법이 선호된다. 미생물을 이용한 원유 회수증진법은 오랜기간 검토되었음에도, 현재까지도 파일럿 규모에서 여전히 평가가 진행 중이다. 본 논문에서는, in-situ 공법에 적용가능한 미생물 중 박테리아의 종 특성과 대사물질에 대해서 살펴보았다.

• 한국해양공학회지
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• 제35권5호
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• pp.382-392
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• 2021

In recent years, floating offshore wind turbines have attracted more attention as a new renewable energy resource while bottom-fixed offshore wind turbines reach their limit of water depth. Various projects have been proposed with the rapid increase in installed floating wind power capacity, but the economic aspect remains as a biggest issue. To figure out sensible approaches for saving costs, a comparison analysis of the levelized cost of electricity (LCOE) between floating and bottom-fixed offshore wind turbines was carried out. The LCOE was reviewed from a social perspective and a cost breakdown and a literature review analysis were used to itemize the costs into its various components in each level of power plant and system integration. The results show that the highest proportion in capital expenditure of a floating offshore wind turbine results in the substructure part, which is the main difference from a bottom-fixed wind turbine. A floating offshore wind turbine was found to have several advantages over a bottom-fixed wind turbine. Although a similarity in operation and maintenance cost structure is revealed, a floating wind turbine still has the benefit of being able to be maintained at a seaport. After emphasizing the cost-reduction advantages of a floating wind turbine, its LCOE outlook is provided to give a brief overview in the following years. Finally, some estimated cost drivers, such as economics of scale, wind turbine rating, a floater with mooring system, and grid connection cost, are outlined as proposals for floating wind LCOE reduction.

• 품질경영학회지
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• 제49권3호
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• pp.375-392
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• 2021

Purpose: Regional gaps and conflicts between regions due to Korea's economic development and industrialization have become important issues, and the issue of balanced regional development at regional level has been discussed as the size of the region has increased recently. Although evaluation of regional balance was attempted through various regional balanced development indexes, it is inappropriate as a standard for determining regional balance in Seoul. Therefore, this study aims to develop objective evaluation methodologies and evaluation indicators for balanced development of administrative districts in Seoul, not existing city and national units. Methods: We looked at existing regional balanced development indexes, and suggested a new regional balanced index reflecting regional development, backwardness, and spatial characteristics in Seoul using factor analysis. Results: As a result of factor analysis, the regional balanced development index for administrative districts and administrative dongs consists of two factors (regional revitalization, financial power) and three factors (commercial density, social security demand, regional retardness), respectively. Then the regional balanced development index scores for 116 administrative districts and 423 administrative dongs are calculated by multiplying each factor by a weight obtained through experts' survey. Conclusion: The proposed regional balanced development index can be used as an objective and quantitative basis for regional balanced development within a city. Further research may include continuously adding new indicators that reflect the direction and scale of development.