• Title/Summary/Keyword: preliminary study

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A Study on Refinement of Benefit Evaluation Methods for Preliminary Feasibility Study of Port Construction (항만건설 예비타당성 조사의 편익 산정 개선에 대한 연구)

  • Shin, Seungsik
    • Journal of Korea Port Economic Association
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    • v.31 no.4
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    • pp.17-38
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    • 2015
  • The purpose of this study is to suggest new methods for evaluating the benefits of a preliminary feasibility study for port construction. For this purpose, this study analyzes the problem of barge loading and unloading systems, and suggests new methods such as using neighboring same kinds of ports first. The study also estimates the benefits for ports that have been evaluated by the existing theory, using the newly suggested methods. The result suggests that there is a possibility to reduce the level of economic feasibility for both general and container-exclusive ports by applying the newly suggested methods.

An Experimental Study on the Mix Properties of Concrete Pavement Incorporating Fly-Ash (플라이애쉬를 혼입한 콘크리트포장의 배합특성에 관한 실험적 연구)

  • Lee, Joo-Hyung;Choi, Seong-Yung;Yun, Kyong-Ku;Jung, Young-Hwa
    • Journal of Industrial Technology
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    • v.17
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    • pp.313-322
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    • 1997
  • As the weight of trucks increases, the need for concrete pavement also increases. Therefore, the addition of fly-ash may improve the properties of pavement concrete as well as recycle fly-ash. A full factorial experiment was performed using the primary variables, such as water-cement ratio, fly-ash substitution ratio, and maximum size of coarse aggregate, as a preliminary study for optimum mixture design for pavement concrete. The results of preliminary study indicates that the addition of fly-ash is the most important factor determining concrete strength, followed by the maximum size of coarse aggregate and water-cement ratio. It, also, shows the relative importance of fly-ash substitution ratio, compared to the water-cement ratio, and the interaction effects between the primary variables. Optimum mixture designs for pavement concrete incorporating fly-ash, that satisfied the target responses, were proposed in terms of fly-ash substitution ratio, water cement ratio and maximum size of coarse aggregate.

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A Comparative Analysis on the Work Importance of Customized and Expansion Remodeling Project (맞춤형 및 증축형 리모델링 공사의 업무중요도 비교·분석)

  • Kim, Min-Jae;Son, Chang-Baek
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2015.11a
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    • pp.66-67
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    • 2015
  • This study compared and analyzed the job importance that site managers perceived by dividing the study scope into customized and expansion remodeling projects and deriving the job descriptions from previous studies. As a result, a total of 7 construction stages and 53 job descriptions were derived. As job importance in customized remodeling projects, removal and demolition works were the most important, followed by preliminary survey, and repair and reinforcement works. In addition, as job importance in expansion remodeling projects, preliminary survey is the most important, followed by civil engineering work, and repair and reinforcement works. It is considered that the job importance of the remodeling projects derived in this study will contribute to improving their job efficiency in the future.

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A Study of Noise Elect for Selecting Eco-friendly Railways (철도노선 선정에 미치는 소음에 관한 연구)

  • Park, Byung-Eun;Kim, Myeong-Gyu;Han, Sung-Woo;Kim, Dong-Gi;Park, Kwang-Heyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.11a
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    • pp.244-247
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    • 2006
  • Railway is superior to the other land transportation systems in aspects of energy efficiency and environmental problems. Energy efficiency and environmental problems are not considered during a preliminary feasibility study. Investment for railway is low because of low B/C in the economical efficiency analysis during the preliminary feasibility study. The body of this paper studies the data which can reflect environmental problems an assessment of environmental impact. Investment for railway would be higher when main environmental elements are considered before the choice of the railway lines.

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Preliminary study on the central nervous system depressant effect of Picrorhiza kurrooa Royle. (Scrophulariaceae) in mice models

  • Rahman, Tasmina;Rahman, Khandaker Ashfaqur;Rajia, Sultana;Alamgir, Mahiuddin;Khan, Mahmud Tareq Hassan;Choudhuri, M Shahabuddin Kabir
    • Advances in Traditional Medicine
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    • v.8 no.4
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    • pp.448-451
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    • 2008
  • Picrorhiza kurrooa Royle. is a well known medicinal plant among the indigenous medical practitioners of India. Present study is the first time to report the activity on the central nervous system. Preliminary study of the hot water extract showed significant depressant activity on the hole board test as evidenced from the ambulation and head dipping scores. The extract showed better activity compared to diazepam on the duration of pentobarbital induced sleeping time.

A Study of Pre-service Chemistry Teacher's Understanding on Entropy

  • Seo, Young-Jin;Hong, Hun-Gi
    • Journal of The Korean Association For Science Education
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    • v.32 no.3
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    • pp.415-427
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    • 2012
  • In this study, we conducted preliminary survey, diagnostic test and in-depth interview in order to study Korean pre-service chemistry teachers' understanding on entropy and investigate how Korean pre-service chemistry teachers deal with the natural phenomenon which is related to entropy conceptions. Firstly, as a result of the preliminary survey, it was found that pre-service chemistry teachers strongly recognized entropy as the degree of disorder. Secondly, the diagnostic test showed pre-service chemistry teachers were mostly confused about whether the entropy of the universe increases during a spontaneous change, and they had a tendency to interpret the natural phenomenon related to entropy change as the change of disorder. Finally, during in-depth interview, after we explained entropy change in all diagnostic test questions with the concept of microstate, pre-service chemistry teachers revealed a better understanding about entropy. Through this research, pre-service chemistry teachers had an opportunity to reflect on their deficiencies of entropy conceptions, which will ultimately help students to approach the concept of entropy more correctly.