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Comparison of Environmental Conditions and Insulation Effect between Air Inflated and Conventional Double Layer Greenhouse (공기주입 및 관행 이중피복온실의 재배환경 및 단열성능 비교)

  • Jayasekara, Shanika N.;Na, Wook H.;Owolabi, Abdulhameed B.;Lee, Jong W.;Rasheed, Adnan;Kim, Hyeon T.;Lee, Hyun W.
    • Journal of Bio-Environment Control
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    • v.27 no.1
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    • pp.46-53
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    • 2018
  • This study was conducted to determine which greenhouse provided good environmental conditions for strawberry production, and performed better at conserving energy. Temperature, RH, VPD, $CO_2$, solar radiation, yield, and fuel consumption were the parameters analyzed. The temperatures of both greenhouses were well controlled in order to provide optimal day and night temperatures for strawberry production. The air inflated double layer greenhouse had higher RH values (more than 90% at night), which led to higher disease occurrence, in comparison to the conventional double layer greenhouse. Furthermore, the air inflated double layer greenhouse had lower VPD values than the conventional double layer greenhouse. Therefore, better RH and VPD were observed in the conventional double layer greenhouse. Higher $CO_2$ concentration was observed in the air inflated double layer greenhouse while the conventional double layer greenhouse ventilated better than the air inflated greenhouse, because of its side ventilators. Moreover, higher solar radiation in the conventional double layer greenhouse resulted in higher yield, in comparison to the air inflated double layer greenhouse. Thus, we can conclude that the conventional double layer greenhouse provided a better environment for crop growth, in comparison to the air inflated double layer greenhouse. Regarding fuel consumption, the air inflated double layer greenhouse had lower fuel consumption than the conventional double layer greenhouse. Therefore, from an energy consumption point of view, we can conclude that the air inflated double layer greenhouse performed better than the conventional double layer greenhouse.

Reciprocal Peer Review and Revision in Writing (동료 간 상호리뷰와 글 수정행동)

  • Jeong, Hei-Sawn;Cho, Kwang-Su;Lee, Nam-Seok;Han, In-Sook;Lee, Jeong-Hee
    • Korean Journal of Cognitive Science
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    • v.23 no.1
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    • pp.47-71
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    • 2012
  • This study examined how students revised their writing after reciprocal peer review and how their revision activities were influenced by the review. Undergraduates in physics class wrote a laboratory reports, exchanged comments with peers, and revised their reports afterward based on the comments they received from their peers. The comparison between the original and the revised drafts showed that students were mainly concerned with micro-meaning revisions, focusing on making changes on individual words, clauses, and sentences. Revisions that dealt with macro-meaning of the texts were not as frequent. Giving and receiving comments influenced later revision activities. Receiving comments on micro-meaning of the texts led to a significant increase in both micro- and macro-meaning revisions. Receiving comments on macro-meaning of the texts, however, did not prompt relevant revision activities. Even when students engaged in macro revision, it was negatively related to writing performance gains in one subgroup, suggesting that even after peers point out macro-problems in their writing, students are not competent to solve the problems yet. The results of the study suggest that more efforts are needed to help them to understand and manipulate the macro-meaning structure of the texts.

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The Performance Analysis of Equalizer for Next Generation W-LAN with OFDM System (OFDM 방식의 차세대 무선 LAN 환경에서 등화기의 성능 분석)

  • Han, Kyung-Su;Youn, Hee-Sang
    • Journal of Advanced Navigation Technology
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    • v.6 no.1
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    • pp.44-51
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    • 2002
  • This paper describes the performance evaluation and analysis of an Orthogonal Frequency-Division Multiplexing (OFDM) system having the least Inter Symbol Interference (ISI) in a multi-path fading channel environment. Wireless Local Area Network (W-LAN) in accordance with IEEE 802.11a and IEEE 802.11b provides high-speed transmission to universities, businesses and other various places. In addition, service providers can offer a public W-LAN service on restricted areas such as a subway. The proliferation of W-LAN has led to greater W-LAN service demands, but problems are also on the rise in offering a good W-LAN service. In particular, urban areas with high radio wave interference and many buildings are vulnerable to deteriorated QoS including disconnected data and errors. For example, when high-speed data is transmitted in such areas, the relatively high frequency generates ISI between Access Points (AP) and Mobile Terminals (such as a notebook computer), leading to a frequency selective fading channel environment. Consequently, it is difficult to expect a goodW-LAN service. The simulation proves that the OFDM system enables W-LAN to implement QoS in high-speed data transmission in a multi-path fading channel environment. The enhanced OFDM performance with 52 sub-carriers is verified via data modulation methods such as BPSK, QPSK and 16QAM based on IEEE 802.11a and punched convolutional codes with code rate of 1/2 and 3/4 and constraint length of 7. Especially, the simulation finds that the OFDM system has better performance and there is no data disconnection even in a mobile environment by applying a single tap equalizer and a decision feedback equalizer to a mobile channel environment with heavy fading influence. Given the above result, the OFDM system is an ideal solution to guarantee QoS of the W-LAN service in a high-speed mobile environment.

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A Study on the Impact of Corporate Publicity on Social Responsibility Perception and Brand Attitude (기업의 공공성이 사회적 책임 인식과 브랜드 태도에 미치는 영향 연구)

  • Kang, Soyoung
    • The Journal of the Korea Contents Association
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    • v.20 no.7
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    • pp.379-391
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    • 2020
  • The growth paradigm that has led Korea for the last few decades is now reaching its critical point. Rather than focusing on the outcomes created by severe competitions of individual companies, a growth based on win-win system and solidarity focusing on public interests is more called for. In this background, I would like to examine the concept of corporate publicness and what factors consist of it. The study aims to verify a causal relationship that corporate publicness affects the corporation's social responsibility and consumers' favorability and credulity toward the company, and looks for the possibility that corporate publicness is recognized as a corporation's substantive competitiveness and an important management activity for its sustainability. The results of the study shows that corporate publicness is composed of 5 dimensions: sincerity, activeness, pursuit of public interest, harmony, and community spirit. Then the study statistically verifies that corporate publicness significantly has a positive impact on the overall evaluation results of a corporation's social responsibility. Lastly, the study confirms that corporate publicness and socially responsible activity of a company have a positive influence overall on the attitude toward the corporate brand. Based on these results, an implication is drawn that strengthening corporate publicness and its practice in action should be emphasized for a corporation to keep making outstanding performances in a sustainable way.

A Study on the Change of Urban Land Use According to the Change of Transportation Accessibility (교통 접근성 변동에 따른 도시 토지이용 변화에 관한 연구)

  • Won, Seok Hwan;Hwang, Chul-sue
    • Journal of Cadastre & Land InformatiX
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    • v.47 no.1
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    • pp.127-142
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    • 2017
  • The purpose of this study is to examine the status of urbanization of Namyangju-Si from 2001 till 2008, analyze the correlation of the change of surrounding land use according to the change of accessibility and analyze the correlation of the change of land use. Based on the result from correlation analysis, I simulated from the view point of interactions between agents of land use and transportation accessibility by using MAS. I tried to forecast, based on space, the change of surrounding land use caused by the change of accessibility. I conducted landscape analysis by using a land registration map. Also, I conducted GIS analysis statistical analysis simulation analysis of traffic data, land use data in order to analyze the correlation of the change of surrounding land use according to the change of accessibility. I could find out a certain pattern that new roads and railroads causes the within 500m adjacent land to change into urban land use, which led me to construct a system through which land use changing phenomenon can be expected according to the change of accessibility. It is expected that it can make the best use of selecting the location where new transportation facilities are constructed.

A Study on the SCM Integration & Green Growth Strategy of Logistic Company in Korea (물류기업의 SCM통합과 녹색성장을 위한 대응방안에 대한 연구)

  • Jin, Yun-Jun;Lee, Yu-Bin;Bae, Ki-Hyung
    • International Commerce and Information Review
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    • v.15 no.2
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    • pp.3-23
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    • 2013
  • In 1997, 180 countries signed the Kyoto Protocol in Kyoto, Japan. The Kyoto Protocol came into force in February 2005. The agreement calls for industrialized nations to cut greenhouse gas emissions by 5 percent from 1990 levels by 2008 to 2012. One of those polices is a modal shift that change from road freight to sea, inland waterway and railroad transportation that is eco-friendly. The increase of road freight brings road congestion, accidents, logistic costs, air pollution and greenhouse gases. Railroads are superior than the other modes of transportation in mass transportability, high speed, timeliness, safety and environmental-friendliness, but the railway industry has been pushed behind in competition. Korean railroads were used by passengers and freight transport popularly until the middle of 20th century, however, by the sudden change of logistics environments, a shaving time efficiency being most important, railroad logistic lost its competitive power against the transportation by truck. From the research which sees consequently investigated a various policy, a system and a law about Chinese logistics industry and present condition of the Chinese goods enterprise and instance analysis of the large Chinese corporation that branch out to undeveloped markets led and a Chinese logistics industry and problem point escape hereafter the heightening of competitiveness plan which is rational under prsenting boil.

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A Critical Review on the Inherent Problems of MOOC (MOOC(Massive Open Online Course)의 근원적인 문제점들에 대한 비판적 고찰)

  • Yang, Dan-Hee
    • Journal of the Korea Convergence Society
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    • v.6 no.6
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    • pp.293-299
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    • 2015
  • MOOC (Massive Open Online Course) is an online course aimed at limited participation and open access via the web. There is even the prospect that MOOC may break down the existing university system and open a new horizon of education. However, MOOC is going differently from the first prospect that it would threat the existing higher education institutions. So this study wishes to provide a starting point of discussion that we can produce and utilize MOOC to fit our situation of higher education by revealing the inherent problems of MOOC. MOOC is a basically online education, so that it cannot help inheriting the essential weakness of the existing one: the interaction, supervision and evaluation. The newly added concept 'massive' raises the problem of class size which is the most sensitive part in the field of education. The concept 'open' reverses a customized education because MOOC is a kind of video clips of a lecture for unspecific massive learners. As a conclusion, we predicts that MOOC will be positioned as a higher education service for very prominent learners in self-led learning ability and people who cannot access even traditional online higher education institutions. Also MOOC is highly likely to be used as a means of Flipped Learning in universities. Therefore, considering these points in the future, we need to develop MOOC to suit these targets.

Analysis of Child-Friendly Environment in a Neighborhood Park in Child-Friendly City - Focused on the Moraetmal Neighborhood Park of Seongbuk-gu - (아동친화도시 근린공원의 아동친화환경 분석 - 성북구 모랫말 근린공원을 중심으로 -)

  • Choi, Jin-Ho;Kim, Ah-Yeon
    • Journal of the Korean Institute of Landscape Architecture
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    • v.47 no.6
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    • pp.87-102
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    • 2019
  • Since the Child Friendly Cities Initiative(CFCI), a UNICEF-led initiative, was first introduced to Seongbuk-gu in 2013, more than half of the districts of Seoul are making efforts to achieve the accreditation of the Child Friendly City(CFC). At this point, when an initiative is transformed from a special policy of a few districts into a general policy of many local governments, we need to examine and check on how friendly urban parks are to children. This study focused on neighborhood parks that tend to be less friendly to children as compared to children's parks and looked into the current status, because neighborhood parks are also well used by users of all ages including children. The evaluation criteria was developed based on the review of domestic and international guidelines of child friendly parks and neighborhood parks. Futhermore, field studies, user questionnaire, and a participatory design workshop were introduced to analyze the status of child-friendly environment of neighborhood parks. Findings are as follows. First, vague definitions of child cause the inconsistency of child-related policies. Second, Neighborhood parks are not conceived as a public space for children. Third, the consideration of youth is relatively low. Fourth, adjacent area of a park turns out not to be child friendly as well.

The Literature Study about the Origin of Sipgan-Sipiji (십간십이지의 기원에 관한 문헌적 고찰)

  • Na, Hyeok-Jin;Kim, Ki-Seung
    • Industry Promotion Research
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    • v.5 no.1
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    • pp.117-124
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    • 2020
  • The purpose of this paper is to find out the origin and significance of Sipgan-Sipiji that Yinyang and five elements are assigned. By looking at the hypotheses that Sipgan-Sipiji may have originated from the ancient Chinese calendar, the contents of the materials recorded in the classical literature, and the records left in the Oracle bone script, we wanted to explore the starting point of Sipgan-Sipiji in Eastern humanities and social sciences that could never be overlooked. Through the literature review of Sipgan-Sipiji, the researcher believes that this code system was completed by Hwangje and his teacher Daeyo, who led paternal clan society in the latter part of the Chinese Neolithic Age, because of supporting the use of the October calendar associated with Sipgan, and because Sipgan in the Oracle bone script seems to keep the sacredness and at the same time to be used to document the time. I believe that this consideration of Sipgan-Sipiji will be helpful for future related research in the process of underlying the research effort of Myeongri Science, such as the security of the logic of the theoretical framework for the theory system and the proof through statistical social science techniques.

Subjectivity of Parents in Refusal of Childhood Vaccination: A Q-methodology Approach (자녀 예방접종 거부 부모의 주관성: Q 방법론적 접근)

  • Cha, Hye-Gyeong;Ha, Eun-Ho
    • Child Health Nursing Research
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    • v.19 no.3
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    • pp.216-227
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    • 2013
  • Purpose: Despite the well-known public health benefits of vaccination, increasing public concern about the safety of childhood vaccinations has led some parents to refuse or hesitate having their children immunized. The purpose of this study was to identify the subjectivity of parents toward refusal of childhood vaccination. Methods: Q-methodology, in which subjective viewpoints are explored and analyzed using a combination of quantitative and qualitative techniques, was used. Thirty-five participants were asked to rank 42 statements on diverse issues of childhood vaccination according to a continuous 9-point scale ranging from -4 for strongly disagree to +4 for strongly agree. Collected data was analyzed using the PC-QUANAL program. Results: The results revealed three discrete groups of parents in the refusal of children's immunization: type I, distrust; type II, concern about side effects, and type III, belief that vaccinations are unnecessary. Conclusion: Special nurse counselors who can provide correct information about vaccination based on the three types should be part of the government policy. Customized education programs to shift viewpoints should be also redeveloped according to the results in this study.