• 제목/요약/키워드: free riding

검색결과 46건 처리시간 0.024초

여수로에서 도수 수치해석 연구 (Numerical Investigation of Hydraulic Jump in a Spillway)

  • 백중철;류용욱;이남주
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2017년도 학술발표회
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    • pp.66-66
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    • 2017
  • 하천에 설치된 저낙차 보의 여수로나 위어는 일반적으로 도수가 발생하도록 설계한다. 이러한 수공구조물위를 통과하는 흐름이 갖는 강한 운동에너지를 소산시키는데 도수는 중요한 역할을 한다. 난류흐름과 도수의 수면부근에서 형성되는 롤러 형태의 와류가 이러한 에너지 소산의 대부분을 유발한다. 이 연구에서는 여수로에서 발생하는 수중 도수 현상을 고해상도 3차원 수치모의를 통해서 재현하고 실험실에서 PIV를 이용해서 관측한 실험결과와 비교분석 한다. 아울러 수치모의 결과는 수중의 바닥면을 따라 발생하는 ?의 내부와 외부 전단층 그리고 도수에 의해서 발생하는 제순한 와류의 동적 거동 특성을 제시한다.

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How Chinese Online Media Users Respond to Carbon Neutrality: A Quantitative Textual Analysis of Comments on Bilibili, a Chinese Video Sharing Platform

  • Zha Yiru
    • Asian Journal for Public Opinion Research
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    • 제11권2호
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    • pp.145-162
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    • 2023
  • This research investigates how users of Bilibili, a video sharing website based in China have responded to carbon neutrality. By conducting quantitative textual analyses on 3,311 comments on Bilibili using LDA topic extraction and content statistics, this research discovers that: (1) Bilibili users have assigned more weight to geopolitical topics (56.3%) than energy (22.0%) and environmental topics (21.7%). (2) When assessing carbon neutrality, Bilibili users considered geopolitical (53.8%) and energy factors (15.8%) more heavily than factors related to the class (9.2%), economy (8.9%), environment (8.7%), and definition (3.6%). (3) More Bilibili users had negative (64.6%) attitudes towards carbon neutrality, with only a small portion of them expressing positive (26.8%) and neutral (8.6%) attitudes. (4) Negative attitudes towards carbon neutrality were mainly driven by geopolitical concerns about the West's approach to China, other countries' free-riding on China's efforts and the West's manipulation of rules, doubts about the feasibility of energy transition and suspicion of capitalists exploiting consumers through this concept. This research highlights the geopolitical concerns behind the environmental attitudes of Chinese people, deepening our understanding to psychological constructs and crisis sensitivity of Chinese people towards environmental issues.

DEA를 활용한 도시철도 노선별 수송효율성 분석 (Transport Efficiency Analysis of the Lines of Urban Railway using Data Envelopment Analysis)

  • 김수현;정헌영;이원규
    • 대한토목학회논문집
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    • 제34권2호
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    • pp.605-616
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    • 2014
  • 본 연구는 우리나라 도시철도들의 수송효율성을 분석하여, 수익성 측면에 있어서의 효율성을 향상시키기 위한 정책방향을 제공하고자 수행되었다. 본 연구를 통해 우리나라 도시철도들의 상대적 효율성을 측정하고, 효율성이 부족한 도시철도 노선에 대해 구조적인 문제가 존재하는지를 분석하였다. 분석대상은 전국 공공기관이 운영하는 17개 도시철도 노선이며, 자료포락분석기법(DEA)으로 노선별 효율성을 분석하였다. 분석된 결과로부터 규모의 경제성을 도출하고, 외부요인으로서 무임 손실비용과 운임제도에 따른 운수수입에의 영향정도를 파악하였다. 이 때 분석을 위한 변수로는 다중회귀분석을 통해 도출된 차량수, 운행횟수 두 생산요소를 투입하여 운수수익을 산출하는 형태로 상정하였다. 마지막으로 자료포락분석기법으로 도출된 효율성값을 다차원척도법(MDS)에 적용하여 전국 도시철도에 대한 수익성 측면의 효율성 향상방안을 제시하였다.

도시철도 역사 승강장의 유니버설 디자인 기준에 관한 연구 (A Study on Universal Design Guideline of the Urban Railway Station: Platform)

  • 강병근;김상운;신동홍;이주형;이주연
    • 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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    • 제21권2호
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    • pp.35-43
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    • 2015
  • Purpose: A large number of the mobility impaired have increasingly used the railway station, so the application of UD(Universal Design) on urban railway station has been interested. However, the current criteria used in domestic areas have concerned about the effective administration of railway station facilities rather than the needs of he mobility impaired. Of diverse facilities in railway station, the platform is considered as an important space due to many transportation users' riding or transfer in railway stations. Therefore, this study aims to explore the detailed criteria in adapting ideas from UD to platform within railway station. Methods: This study explores the criteria by evaluating findings from previous studies. First, all criteria related to platform in domestic and foreign areas are taken together and analyzed, and appropriate criteria first are established. Based on these, the current situation of platform facilities in railway station is evaluated. Then, the detailed criteria applicable to railway station platform are concluded, by reviewing types of the mobility impaired and principles of UD. Result: Findings from this study are as follows. First, the current criteria applied to railway station platforms lack ideas of UD, while the criteria used in foreign countries adequately reflect the ideas of UD on railway station platforms; therefore, the better criteria applicable to platform facilities in domestic railway station are necessary. Second, standard criteria used in domestic areas with newly additional criteria suggest that platform facilities should be established according to those criteria. Taken together, the better platform facilities should be provided to railway users through the application of UD to railway station platforms. Implications: For the future users in railway station platforms, the additional research on criteria of UD as well as diverse types of spaces within railway stations should have been continued.

경제발전 및 정보의 외부성에 따른 최적 은행구조에 대한 고찰 (Information Externality, Bank Structure, and Economy)

  • 도보은
    • KDI Journal of Economic Policy
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    • 제27권1호
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    • pp.39-79
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    • 2005
  • 본 연구는 은행집중도 확대 등 독점적 은행구조의 비교우위 가능성을 검토하였다. 즉, 신용평가기관(Credit Bureau)의 정착, 신용정보의 거래활성화 등 금융제도가 선진화되면서 나타나는 정보의 외부효과 증대에 따라, 또한 경제발전단계에 따라 최적 은행구조가 어떻게 달라질 수 있는지를 분석하였다. 본 연구의 결과는 다음과 같다. 경제개발 초기단계인 저개발국가와 자본시장이 발달하고 금융제도가 선진화되면서 정보의 외부성이 높아진 선진국의 경우는 독점적 은행구조가 장기균형자본축적에 효과가 있었다. 이러한 결과는, 은행과 차입자 간의 비대칭적인 정보구조가 상존하는 가운데 경제 내의 신용리스크가 큰 경우 또는 정보의 외부효과가 높아 무임승차(free riding) 위협이 큰 경우에는 독점적인 은행구조가 바람직함을 시사한다. 본 연구는 최근 금융산업에서 발생하는 인수합병의 경제적 효과를 설명하는 새로운 분석방법을 제시하고 있으며, 우리나라 및 세계 각국의 인수합병 관련 규제완화의 이론적 근거를 제공할 수 있다.

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초중등 과학교사들의 과학연구윤리교육에 대한 인식 (The Perceptions of Science Teachers Regarding Science Research Ethics Education)

  • 김성덕;김효남
    • 한국초등과학교육학회지:초등과학교육
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    • 제32권4호
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    • pp.393-403
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    • 2013
  • The purpose of this study was to investigate the perception of school teachers in science research ethics and perception of science research ethics education. A survey was administered for this study and a total 167 elementary and secondary teachers studying in K University graduate school participated. The survey was organized to examine participants' 1) science research ethics awareness, 2) status of science research ethics education, and 3) needs for science research ethics education, and 4) the perception of the direction of the science research ethics education in school. Each item was responded using either 1 to 5 Likert type scale, multiple choices questionnaires. The results were as follows: both of elementary and secondary school teachers showed above average interest in science research ethics and secondary school teachers showed significantly higher interest than elementary school teachers(p<0.05). In degree of awareness of science research ethics, plagiarism (M=3.98) was the highest, followed by free-riding(M=3.78), the scientist's social responsibility(M=3.71), and forge(M=3.61). In response science research ethics problem occurs in science education activities more than the average(M=3.39). Teacher's response on the teaching of science research ethics ranges from 3.02 to 4.47, but each science research ethics elements was showed a large deviation. Elementary and secondary school teachers responded that science research ethics education needed(M=4.34). Science research ethics education should be included in the school curriculum. Eighty-five percent of the teachers responded that the science research ethics education should be started from elementary school. 'Discussion-type classes with examples' was preferred as an effective teaching. And teachers needed 'instructional materials' and 'teachers training' for science research ethics education.

고려 말 신흥사대부의 개인문집에 나타난 아동양육 (I) - 아동기 개념화와 일상생활을 중심으로 - (A Study on Child Rearing in the High Officials' Collection of Works During the Late Period of the Goryo Dynasty: Focusing on the Conception of Children and their Activities in Everyday Lives(I))

  • 신양재
    • 대한가정학회지
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    • 제43권12호
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    • pp.79-96
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    • 2005
  • The purpose of this study is to explore the conceptions of children and their activities in everyday lives during the late period of the Goryo Dynasty. The historical method was used and the materials for analysis were the literatures written from the late thirteenth century to the fourteenth century in the Goryo Dynasty, such as 'the Ikjaijip'(익재집), 'Mokeunjip'(목은집), 'Yangchonjip'(양촌집). According to the results, the perspective on the nature of a chad was that children were inherently good with the true character which was given from natural laws and that each child was born with different natural endowment. Also, the notions on child development were that the infancy was a pure and perfect period which us not contaminated by temperament and worldly desires, instead of the developmental model that childhood is as a stage and the child must develop from the state of incompetence to the state of maturity. In addition, there were the principles for development that were keeping the innate ideal state and fostering it from the earliest time as infants were born with innate ideal state or ability. The concepts of children's characteristics were considered that they were inclined to make much noise and movement, but to have the plain and straightforward expressions and consistency in their feelings and everyday activities. And intelligent abilities for learning were often considered as desirable traits. In everyday lives, children did the household chores such as caring for livestock and silkworms or embroidering. Among their games were exploring activities, free plays using natural materials, pretend-plays, bamboo-stilts riding, and Yutnori.

홍삼복용이 노인들의 유산소 운동시 발생된 활성산소에 미치는 영향 (The Effects of Red-ginseng Intaking on Free Radical Produced During Aerobic Exercise in the Elderly)

  • 최종환;김영수;이규문;김현주
    • Journal of Ginseng Research
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    • 제28권1호
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    • pp.27-32
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    • 2004
  • 노인들의 고강도 유산소운동시 많은 산소요구량에 의하여 산화적인 스트레스가 증가하고, 결과적으로 함께 발생되는 활성산소는 MDA수준을 증가시킨다. 이렇게 노인들의 강도 높은 운동 중에 발생되는 활성산소에 홍삼복용이 어떠한 영향을 미치는 지를 알아보기 위하여 젊은이들과 비교하여 연구하였다. 노인들은 젊은이들과 함께 홍삼복용 전 후에 걸쳐 안정시, 운동직 후, 그리고 회복기 30분의 MDA수준이 유의하게 낮아진 것으로 나타났다. 따라서 홍삼복용은 젊은이들뿐만 아니라 노인들의 축적된 과산화지질을 제거하거나 과산화지질의 생성을 억제하는 항산화 효과가 있음을 시사한다.

WTO 보복조치의 동등요건에 관한 연구 (A Study on the Equivalence Requirement of WTO Retaliation)

  • 강수미
    • 한국중재학회지:중재연구
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    • 제23권2호
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    • pp.81-113
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    • 2013
  • The World Trade Organization (WTO) offers remedies for non-compliance by the introduction of compensation or retaliation in the Dispute Settlement Understanding (DSU). There are no the provisions under the WTO DSU and it seems unclear what retaliation is attempting to achieve. Therefore, it is unclear whether the goal of WTO retaliation is to induce compliance or to restore the balance between the rights and the obligations of WTO members. It has been claimed the WTO has a strong dispute settlement system by providing retaliation when the recommendations and rulings of Dispute Settlement Body (DSB) are not complied with. But this seems to be inadequate to bring about effective and timely compliance. Especially there is a problem with free riding by a violating member because the level of retaliation is determined from the expiration of a reasonable period of time, providing an incentive to delay compliance. Also the level of the suspension of concessions or other obligations authorized by the DSB is equivalent to the level of nullification or impairment, according to DSU Article 22.4. However, if the member concerned objections to the level of the suspension proposed, the matter shall be referred to arbitration. The arbitrator shall not examine the nature of the suspension of concessions or other obligations to be suspended but shall determine whether the level of such suspension is equivalent to the nullification or impairment. The arbitrator makes an assessment standard of equivalence by comparing the suspension of concessions or other obligations and the nullification or impairment calculated in terms of the amount of trade. But it is necessary that other standards replace the quantitative standards when the level of the nullification or impairment cannot be quantified by concrete damages.

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퍼지논리와 가상가치법 혼합을 통한 현상적 건축미의 매력가치 - 노들섬 문화센터 시설이용료를 가치 척도로 - (Attractiveness Valuation of Phenomenal Architectural Aesthetic by Mixing the Fuzzy Logic with Contingent Valuation - Availing the Use Fares of Facility within Nodle Islet Cultural Center as Valuation Scale -)

  • 이동주;고은형
    • 대한건축학회논문집:계획계
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    • 제34권5호
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    • pp.3-10
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    • 2018
  • The purpose of this study is to estimate the attractiveness value according to the preference level on architectural aesthetic. This research starts from the concept that aesthetic is phenomenon and from the viewpoint of 'attraction value' which affects goods. Interactive internet surveys were conducted for 500 citizens of Seoul metropolitan city who are potential users of the Nodle Islet Cultural Center. Based on the scenarios and questionnaires with fuzzy models, we have examined the evaluation of architectural aesthetic and monetary willing-to-payment, and estimated the economic value by preference level of architectural aesthetic through linear regression analysis. The main results of the study are as follows: First, the economic value of the Nodle Islet Cultural Center was estimated at ?15,683.43/person. Residents of Seoul metropolitan city were willing to accept the increase in the above-mentioned amount of the facility fares when their preferred works (average 86.81 points) were constructed. (P <0/05) Second, it is confirmed that the economic value increases dramatically as the preference level of architectural aesthetic increases. Third, it is presumed that the infinite valuation of architectural aesthetic and the problem of free riding coexist in the estimation of economic valuation of architectural aesthetic for public buildings. Fourth, by mixing the fuzzy logic with contingent valuation method, starting point bias and no response biases that happened in contingent valuation could be disappeared. bias elimination must be considered seriously because another bias could be happened in full process of the research. The results of this study will serve as a basis for spreading architectural aesthetic value-oriented research from the vague and obscure aesthetic-centered discussion on the existing architectural aesthetic. In addition, it will be an opportunity to draw institutional application and utilization strategy of architectural aesthetic through architectural aesthetic value research.