• Title/Summary/Keyword: 부정적 외부효과

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A Study on Reducing Method for Stack Effect in High-rise Building (고층 건축물 연돌효과 저감 방법에 대한 연구)

  • Kim, Jin Soo
    • 한국방재학회:학술대회논문집
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    • 2011.02a
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    • pp.66-66
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    • 2011
  • 중위도 이북의 건물에서 고층건물의 혹한기 연돌효과는 건물의 여러 가지 기능에 큰 영향을 미치며, 승강기 승강로는 화재시 차압 때문에 연기의 주된 전파통로가 된다. 외피의 밀폐성능을 높여 건물 내부의 연도효과를 줄일 수 있으나, 외피의 밀폐기능은 비상시 피난을 위해 피난경로를 개방하는 순간 일시에 무력화된다. 또한 건물 외피의 밀폐성능이 우수할수록 연돌효과 그 자체로써 건물외피에 미치는 구조적 영향이 커진다. 고층부의 연돌효과는 외피를 밖으로 밀어내는 작용이므로 풍하측에서는 마이너스 풍압에 더하여 건물 외피에 부담을 증가시킨다. 그러므로 고층건물에 발생하는 혹한기 연돌효과의 영향을 정리하자면 다음과 같다. ${\bullet}$ 건물 외벽 및 창문에 미치는 구조적 영향 ${\bullet}$ 제연 시스템의 기능 저해 ${\bullet}$ 승강기 문 개폐 장애와 소음 등 설비 기능의 부정적 영향 ${\bullet}$ 공조기능 장애 ${\bullet}$ 화재시 승강기 승강로 등 수직 샤프트를 통한 연기 전파 혹한기 건물 안팎의 온도차가 40K일 때 높이 600m인 초고층 건물 최상층에 발생하는 연돌효과에 의한 차압은 풍속으로 환산할 때 32m/s에 달한다. 그러므로 초고층 건물 설계시에는 최상층의 풍하측에 설계상의 예상 최대풍속에다 이러한 환산풍속을 더한 고속 풍력이 창문을 밖으로 밀어내는 것으로 보아야 한다. 또한 공조 및 환기시스템에서는 이러한 차압을 고려하지 않으면 고층부에서 환기 성능이 무력화될 수 있다. 다음과 같은 방법들을 이용하여 고층건물의 연돌효과를 효과적으로 줄일 수 있다. 1) 계단실의 연돌효과 저감 방법 계단실에 발생하는 연돌효과에 의한 차압은 계단실에 상승기류를 발생시킨다. 이러한 차압과 상승기류는 계단실 상하부를 개방하면 자연적으로 평형을 이루게 되므로 별도의 제어가 필요 없게 된다. 또한 화재감지기와 연동하여 상하부 외벽의 개구부를 열어두게 되면 피난상황에 따라 문이 여닫힘으로써 발생하는 압력상태의 변화를 고려할 필요가 없게 된다. 2) 승강기 승강로의 연돌효과 승강로의 상하부에 대규모 개구를 두면 대규모의 외기가 도입되어 상승 유동 후 배출되므로 승강로 내부 온도 저하로 연돌효과가 저감되고, 승강로로 유입된 연기는 대규모의 외기에 희석되어 농도가 낮아지고 대부분 외부로 배출된다. 3) 샤프트 복합효과를 이용하는 방법 거실 평면적에 비해 승강기나 계단이 아주 많고 누설틈새 등 개구의 면적 합계가 크면 샤프트들이 서로 복합효과를 이루어 연돌효과에 의한 차압이 줄어든다. 연돌효과 제어용 샤프트를 하나 더 보조적으로 설치함으로써, 보조샤프트에 의해 발생하는 차압으로 거실을 가압 혹은 감압하여 문제가 되는 차압을 어느 정도 상쇄할 수 있다.

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An Explorative Study of Big Companies' Expansion Strategies to Digital Businesses (대기업의 디지털 산업 확장 유형의 탐색적 연구)

  • Kim, Iljoo
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.16 no.6
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    • pp.241-248
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    • 2021
  • Firms have many ways to expand their businesses including M&A. Big companies in online and offline businesses show different ways of expansion with different objectives to expand their digital businesses quickly. Expansions for technical reasons are to acquire technologies they do not have while those for business reasons are M&A for offline companies to have competence in markets by acquiring online companies. Other ways of expansions include spin-off and group participation after investments for startups. Various ways of expansions are chosen because they are optimal choices depending on situations the companies face, and they have different strengths and weaknesses. To analyze the strengths and weaknesses of those options for expansion at this stage would be academically valuable, and also practically meaningful in terms of providing insights for companies' decision making in choosing opitions for expansions. M&A of online companies to make multi-channels by offline companies have risks of failing to internalize online companies and have enough synergy effects. Also, spin-off is a relatively less risky way of expansion while the speed of expansion is slower than establishing external startups with some shares of equity and making them as affiliated companies. External startups are good for speed of expansion while there are risks of legal regulations and negative awareness by the public.

Analysis and Optimization of ICT Application in Construction Phase (시공단계 ICT 도입 효과분석 및 최적화 방안)

  • Go, Tae-Yong;Kim, Ryul-Hee;Lee, Dong-Eun
    • Journal of the Korea Institute of Building Construction
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    • v.19 no.2
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    • pp.175-184
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    • 2019
  • This paper presents a modeling prototype that optimizes construction processes implementing information communication technology (ICT). Using "IAMB", each and every actual steps of the construction process may be defined visually and explicitly by elaborating ICT to improve productivity and management efficiency. It contributes to identify the features on what parts of construction task are covered by ICT, and the effects of ICT on process performance. After analyzing 10 real project cases, ICT application types are classified into four categories according to ICT type, job functions that ICT applied, and the project phase in which ICT used. As a reuslt, it was confirmed that the positive outcomes on the construction process were beneficial to mostly the general contractors and mainly obtained by automated information processing, external consignment and consistent information use. Negative effects, which were occurred by mainly manual manipulation and duplication of information handling, were accrued to general contractors minimally, but to subcontractors maximally. Expert focus group commends that several important issues should be considered when implementing ICT.

A Study of Evaluation for Reforestation and Silviculture Policy in Korea (조림·육림정책에 대한 인식도 평가 연구)

  • Nam, Sunghyun;Kim, Sebin;Kwon, Kiwon;Jeon, Hyonsun
    • Journal of Korean Society of Forest Science
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    • v.97 no.1
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    • pp.10-21
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    • 2008
  • The purpose of this study is to evaluate the fitness of policy topics and policy making process, the reasonableness of policy enforcement, the backing of public opinion and the results and effects of policy enforcement for the reforestation and silviculture policy in Korea. Most of the fitness of policy topics was evaluated positively, but the change of species of reforestation trees from a coniferous tree to broad-leaved tree was evaluated negatively. Most of the fitness of policy making process and the reasonableness of policy enforcement was evaluated positively, but the conflicts with other forest policy was evaluated negatively. And the limits of self-judgement of the responsible person needs to be extended. The backing of public opinion was evaluated positively but that of statesman was evaluated negatively. And the most of the results and effects of policy enforcement was evaluated positively but the economic contribution of the policy was evaluated negatively.

A Study on Work Safety and Standard Contract for Popular Culture Production Staff (대중문화예술제작물스태프의 작업 안전과 표준계약에 관한 소고)

  • Kim, Si Yeol;Lee, Kyung Ho
    • The Journal of the Korea Contents Association
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    • v.19 no.10
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    • pp.630-640
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    • 2019
  • A series of recent events have laid the groundwork for discussions on the safety issues regarding production staff in the popular culture industry. In Korea, the standard contract has been pursued as a means of dealing with issues involving popular culture production staff. However, the existing standard contract failed to incorporate the characteristics and requirements in today's market, which greatly restricted its efficacy in real-world cases. Therefore, this study seeks to significantly improve the provisions in the standard contract that govern obligations between contractual parties, and the work safety of the production staff. To this end, considering the main causes of safety accidents and actual contracts, this study groups contractual provisions into several categories: the removal of adverse factors affecting optimal competency, factors causing individual staff's negligence, and external factors causing negligence. Then, this study proposes specific provisions to be included in each category.

Dynamic Interindustry Linkages Analysis of Human Resources Development in the field of Information Technology (정보통신분야 인력양성에 대한 동태적 산업연관분석)

  • Lee, Jung-Mann;Cho, Sang-Sup
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.4
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    • pp.1621-1627
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    • 2011
  • This study investigates both backward and forward multipliers of human capital in the field of information technology in order to evaluate human resources programs which were executed in the public sectors. Dynamic interindustry linkages analysis was employed as a methodology after classifying human capitals related to information technology into 9 industries. First, empirical findings showed that there are economic externalities in the IT HRD programs when the formation of human capital increases with more investment in them. Second, another finding was that the effect of HRD programs could be powerful when HRD programs were closely connected with R&D programs, showing that R&D programs among IT HRD programs have huge backward linkage effect. In addition, IT service sector has its own spill-over effect to other industries. Third, however, small budget and one off HRD programs should be considered as a negative price synergy effect. Finally, overall economic feasibility of IT HRD programs turned out to be excellent with consideration of their own economic direct and indirect effect.

Korean Wang-ta: Characteristics and Prevention Program (한국의 왕따와 예방프로그램)

  • Keumjoo Kwak
    • Korean Journal of Culture and Social Issue
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    • v.14 no.1_spc
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    • pp.255-272
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    • 2008
  • When observing the subjects and seriousness of Korea's Wang-ta, it is urgent that we know the characteristics of Wang-ta and its conditions. In this study, we investigated the definition of Wang-ta, which partly differs from bullying. Also, the phenomenal characteristics of collectivism, the victimization of an individual once stigmatized in the Wang-ta process, the generalization of the Wang-ta process where bullies extend their territory into general students were examined. Moreover, external environment such as Korea's school environment, negative house environment, and collective culture were examined. The three general structures in researching Korea's Wang-ta were presented. The first structure consists of a bully, victim, and a bully-victim. The second structure focuses on the certain groups, which consists of followers, outsider, and the defender. The last structure deals with the psychological characteristics of the participant roles, which are the bully, reinforcer, assistant, defender, victim, and outsider. Wang-ta prevention programs, which reflects the characteristics of Wang-ta, are presented. Implications on future Wang-ta prevention programs are discussed.

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Community Orchestra Educational Activities and Development of Poor Children (지역사회 오케스트라 교육 활동과 빈곤아동 발달)

  • An, Eunmi
    • Korean Journal of Social Welfare
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    • v.68 no.1
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    • pp.225-248
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    • 2016
  • This study explores the effects on development of poor children by community-based orchestra educational activities and the orchestra educational activities factors for promoting the effects using longitudinal data are those collected for "The Evaluation of the Impact of Our Neighborhood Orchestra on Children's Learning" made by the Seoul Philharmonic Orchestra. For these purposes, this study employed a latent growth model analysis of the factors such as depression, aggressive behavior, communality and interpersonal relationship of development of poor children and evaluation, satisfaction, outsiders'attention and participation of facilitative factors. The result shows that they displayed significantly positive development in depression, aggressive behavior, and interpersonal relationship. It appears that the evaluation on music achievement had a positive impact on the rate of change in communality, while the evaluation on attitude had an impact in the initial value of depression, aggressive behavior, and communality, also the sense of satisfaction had a positive impact on the initial value of communality and interpersonal relationship in conditional models. And parents' attention and participation had a negative impact on the initial value of aggressive behavior, while the attention and participation of the community showed a positive impact on the initial value of depression and aggressive behavior. Based on these results, this study attempted to broaden the understanding of the development of poor children taking part in orchestra-based educational activities and provide a practical basis for social workers' direct invention, and look for new ways by shedding light on the merits of the cultural/art education of poor children that engage in the community-based orchestra educational activities.

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Factors Affecting the Mental Health of Adolescents : Mediating Effects of Alcohol Drinking (청소년의 심리건강 영향요인: 음주의 매개효과)

  • Sohn, Minsung;Kim, Mi Sun;Yoon, Ki Chan;Choi, Mankyu
    • The Journal of the Korea Contents Association
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    • v.13 no.2
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    • pp.359-369
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    • 2013
  • In this study, the relationship between social support and adolescent mental health was examined. A primary aim was to investigate how family, school, and friends affect adolescent mental health including depression, stress, and anger issues. This study also intended to investigate the indirect effect of these factors through the mediator, problem drinking. The study used survey data collected from the "2010 The Study on Mental Health of Korean Adolescents" conducted by National Youth Policy Institute, and 942 subjects were selected for this study. The study hypotheses were tested using SEM (Structural Equation Modeling) analysis. Analyses revealed that the appropriate functions and roles of the family members had the effect of promoting mental health of adolescents. Inappropriate functions and roles of the family members induced problem drinking, and this eventually had a negative impact on mental health causing depression, stress, and angel problems. Results also showed that having more friends who drink alcohol or smoke cigarette had no direct effect on the mental health of adolescents; however, there was an indirect effect through the mediator variable, problem drinking. The finding of this study revealed the need and importance of appropriate social support system and environment in order to promote mental health of adolescents.

Agronomic Effect of High Quality Compost mixed with Brown Seaweed for Environmentally Benign Organic Farming (해초 혼합 기능성 희비의 작물재배 효과)

  • 손상목
    • Korean Journal of Organic Agriculture
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    • v.10 no.2
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    • pp.95-109
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    • 2002
  • This study focussed to find out the agronomic effect of high quality compost mixed with brown seaweed and to determine the optimum mixing rate of seaweed to compost for environmentally benign organic farming. The experiment was conducted in lysimeters at Experimental Farm of Dankook University with Chinese Cabbage(Bulam #1), and the crop growth such length and width of leaf, biomass of Chinese Cabbage were checked, the content of chlorophyll, sugar, vitamin C, nitrate in outer leaf and idler leaf was determined. It was observed that nitrate content was dramatically decreased in the plot of mixture with seaweed, while biomass and content of Vitamin C were increased steeply in the plot of mixture with seaweed. The best result was gained the 0.25% mixture of brown seaweed with compost.

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