• Title/Summary/Keyword: Maritime Technology

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The Variations in Some Needle Characteristics of Pinus thunbergii Populations in Korea (침엽형질상(針葉形質上)으로 본 한국산(韓國産) 해송집단(海松執團)의 변이(變異))

  • Lee, Bong Soo;Lee, Kang Young;Yim, Kyong Bin
    • Journal of Korean Society of Forest Science
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    • v.63 no.1
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    • pp.35-41
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    • 1984
  • The attempts in this study were made to evaluate the variations in some needle characteristics of Pinus thunbergii between individual trees within population, between populations and between the hypothesized climatic districts. This species occurs naturally along the southern seacoast of Korea penninsula having a relatively mild maritime climate. The followings are the summarized results. The coefficients of variation of the needle volume and needle serration density were generally higher than those of any other traits studied. The significant differences of variations of needle cross section form factor between individual trees within population at 1% level, except only the Young gwang population, were affirmed. In the case of the eastern seacoast district, where the three study populations are included, significances of variation differences were calculated, 5% level at needle serration density and cross section area and 1% Level at needle volume. The very high significant difference of the variations of needle cross section form factor and needle longitudinal form factor were shown between population of the western seacoast district and 5% Level significance at needle volume in the southern seacoast district. The high significant differences between districts in respect to needle cross section form factor and cross section area were calculated. The Duncan's multiple range test showed the dissimilarity of the said characteristics between the hypothesized climatic districts. Summing up the results obtained so far, individual tree and population variations were markedly noted statistically and these may be extended to the silvicultural technology.

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Comparative Study of the Effects of the Intermodal Freight Transport Policies (인터모달 추진 정책과 효과에 관한 비교연구)

  • Woo, Jung-Wouk
    • Journal of Distribution Science
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    • v.13 no.10
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    • pp.123-133
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    • 2015
  • Purpose - The Korean government has devised intermodal transportation policies and granted subsidies to shippers and logistics companies that made a conversion of transportation means through the policies. This provides support by expanding the complex uniform railroad transportation and overhauling the deteriorated railroad facilities. As for 2013, however, the freight transportation percentage of railroad was 4.5% in tons and 8.5% in ton kilometers. Meanwhile, since the 1990s, developed countries such as the U.S. and Europe have been trying to expand intermodal freight transport with a legal and institutional support to build a logistics system corresponding with social and economic environmental changes. In this study, I set out to examine the effects of the intermodal freight transport policies in the EU and the U.S., and to explore the direction of setting up a rail intermodal transport system in South Korea. Research design, data, and methodology - The paper used a qualitative research methodology through the literature review. First, was an overview of Intermodal transportation in the EU, U.S. and UN. Second, it describes the development of transport in Europe and the U.S. with particular emphasis on intermodal freight transport. Third, it explores the direction of setting up a intermodal freight transport in South Korea. The last section contains concluding remarks. Results - As for the EU, it has been promoting integration between transport and intermodal logistics network designs while utilizing ITS or ICT and supports for rail freight intermodal by giving reduction to a facilities fee or subsidizing for rail freight in order to minimize the cost of external due to freight transport. On the other hand, as for the U.S., it has been made up of an industrial-led operating project and has been promoting it to improve accessibility between intermodal hubs and cargo terminals through intermodal corridor program, and an intermodal cargo hub access corridor projects, etc. Moreover, it has tried to construct intermodal transport system using ITS or ICT and to remove Barrier. As a result, in these countries, the proportion of intermodal freight transport is going to be the second significant transport compared with rail and maritime transport. An Effective rail intermodal transport system is needed in South Korea, as seen in the case of these countries. In order to achieve this object, the following points are required to establish radical infrastructure policy; diversify investment financing measures taken under public-private partnerships, legal responsibilities, improvement of utilization of existing facilities to connect the railway terminal and truck terminal, and enhancement service competitiveness through providing cargo tracking and security information that combines the ITS and ICT. Conclusions - This study will be used as a basis for policy and support for intermodal freight transport in South Korea. In the future, it is also necessary to examine from the perspective of the shipper companies using the rail intermodal transport, ie, recognition of shipper, needed institutional supports, and transportation demand forecasting and cost-effective analysis of the railway infrastructure systems improvement.

A Study on Interoperability of Geo-sensor Based Outcomes : Focusing on Korean Land Spatialization Program (센서기반 응용시스템간 상호운용성 확보에 관한 연구 : 지능형국토정보기술혁신사업을 대상으로)

  • Park, Jae-Min;Jung, Yeun-J.;Park, Kwan-Dong;Kim, Byung-Guk
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.27 no.5
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    • pp.517-528
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    • 2009
  • Korean Land Spatialization Program (KLSP) is a R&D program of the National GIS Project for developing ubiquitous GIS technologies under control of Ministry of Land, Transport and Maritime Affairs. The first program from 2006 to 2012, initiated with $132 million of national fund and $42 million of private matching fund. Aiming 'Innovation of the GIS technology for the ubiquitous Korean land', KLSP consists of five core research projects and one research coordination project. The coordination project's purpose is to practically utilize and commercialize the results of core research projects. Korean Land Spatialization Group (KLSG) is planning a test-bed for testing, integrating, and exhibit- ing the KLSP's outcomes. Integrations of the outcomes are mandatory for the successful KLSG Test-Bed. The main objective of this paper is to introduce KLSP test-bed and three methodologies for integration of the outcomes in KLSP. As a plan of integrations, especially, this paper proposes SWE SOS (Sensor Observation Service) prototype to achieve interoperability of the geo-sensor networks.

Serotype and Enzymatic Profile of Crypfococcus neoformans Isolates from Clinical and Environmental Sources in Korea (한국의 임상과 자연환경에서 분리된 Cryptococcus neoformans의 혈청형과 효소생성능)

  • Hwang, Soo-Myung;Oh, Kwang-Seok;Lee, Kyung-Won
    • Korean Journal of Microbiology
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    • v.42 no.4
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    • pp.257-264
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    • 2006
  • Fifty eight Cryptococcus neoformans strains isolated from clinical and environmental sources in Korea were examined for their serotypes and extracellular enzyme activities. Among the 51 strains isolated from clinical sources, 48 strains were serotype A (94.1%), 2 strains were serotype B (3.92%), and 1 strain was serotype D (1.96%). All seven environmental strains isolated from pigeon excreta were identified as serotype A. All isolates of C. neoformtans were positive for the production of extracellular proteinase and phospholipase. In the API-ZYM system, all fifty eight isolates produced alkaine phosphatase, esterase C4, esterase lipase: C8, leucine arylamidase, acid phosphatase, naphthol-AS-BI-phosphohydrase, $\alpha$-glucosidase and $\beta$-glucosidase. Thirty nine isolates (67.2%) of C. neoformans produced N-acetyl-$\beta$-glucosidase. Two isolates, serotype B, and B only one serotype A produced $\beta$-glucuronidase. Analysis of enzymatic profiles to 21 enzymes revealed four biotypic patterns among the 58 strains. The enzymatic patterns of C. neoformans isolated from clinical and environmental sources represented a significant relationship with the serotypes.

Monitoring of Formaldehyde Concentration in Exhibition Hall Using Passive Sampler (Passive Sampler를 이용한 유물 전시관내 폼알데하이드 농도 모니터링)

  • Lee, Sun Myung;Lim, Bo A;Kim, Seojin
    • Journal of Conservation Science
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    • v.33 no.5
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    • pp.319-329
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    • 2017
  • In this study, formaldehyde concentrations in two exhibition halls were monitored using a passive sampler from May 2012 to April 2013. Formaldehyde concentrations in the exhibition halls were 5 to 36 times higher than concentrations outdoors. Concentrations inside the exhibition room and showcase varied according to pollutant source, HVAC(heating, ventilation, air conditioning)system and environment management. The formaldehyde concentration levels were corrected according to a standard method prescribed by Indoor Air Quality Management Law of the Ministry of Environment, Korea. As a result, Most concentration levels exceeded the exhibition standard of the Ministry of Environment($100{\mu}g/m^3$) and artifacts conservation standard of Tokyo National Museum($50{\mu}g/m^3$). Seasonal concentrations in the exhibition room and showcase were in the order summer>fall>spring>winter. Formaldehyde emissions increased in summer when air temperature and relative humidity are both high. Formaldehyde concentration distribution according to the temperature and relative humidity showed positive correlation. Air temperature showed good correlation because $R^2$ was in the range of 0.8~0.9. Analysis of formaldehyde emission characteristics in the exhibition hall would be helpful in efforts to improve indoor air quality.

A comparative analysis of cell cycles in diploid and induced triploid tissues in marine medaka(Oryzias dancena) (해산송사리(Oryzias dancena) 2배체와 유도 3배체 조직의 세포주기 비교)

  • Park, In-Seok
    • Korean Journal of Environmental Biology
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    • v.37 no.4
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    • pp.735-740
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    • 2019
  • The aim of this study was to conduct a comparative analysis of the diploid and induced triploid cell cycles in marine medaka, Oryzias dancena, tissues. The mean fraction of cells in the G1, S, and G2+M phases was 85.5%, 7.6%, and 6.9%, respectively, in the tail fin tissues of diploid fish and 91.2%, 3.6%, and 5.2%, respectively, in those of induced triploid fish. The mean fraction of cells in the G1, S, and G2+M phases were 78.4%, 10.6%, and 11.0%, respectively, in the liver tissues of diploid fish; 86.2%, 5.9%, and 7.9%, respectively, in those of induced triploid; 79.3%, 9.4%, and 11.3%, respectively, in the gill tissues of diploid fish; and 85.7%, 5.4%, and 8.9%, respectively, in the induced triploid fish. The differences among the tissues were statistically significant within both the diploid and induced triploid fish (p<0.05). Mitosis was more active in each tissue of the diploid fish than in the corresponding tissues of the induced triploid fish and mitosis was more active in the liver and gill tissues than in the tail fin tissues in both the diploid and induced triploid marine medaka.

Headword Finding System Using Document Expansion (문서 확장을 이용한 표제어 검색시스템)

  • Kim, Jae-Hoon;Kim, Hyung-Chul
    • Journal of Information Management
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    • v.42 no.4
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    • pp.137-154
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    • 2011
  • A headword finding system is defined as an information retrieval system using a word gloss as a query. We use the gloss as a document in order to implement such a system. Generally the gloss is very short in length and then makes very difficult to find the most proper headword for a given query. To alleviate this problem, we expand the document using the concept of query expansion in information retrieval. In this paper, we use 2 document expansion methods : gloss expansion and similar word expansion. The former is the process of inserting glosses of words, which include in the document, into a seed document. The latter is also the process of inserting similar words into a seed document. We use a featureless clustering algorithm for getting the similar words. The performance (r-inclusion rate) amounts to almost 100% when the queries are word glosses and r is 16, and to 66.9% when the queries are written in person by users. Through several experiments, we have observed that the document expansions are very useful for the headword finding system. In the future, new measures including the r-inclusion rate of our proposed measure are required for performance evaluation of headword finding systems and new evaluation sets are also needed for objective assessment.

Performance of Oscillating Water Column type Wave Energy Converter in Oblique Waves (사파중 진동수주형 파력발전장치의 성능평가)

  • Jin, Jiyuan;Hyun, Beom-Soo;Hong, Keyyong;Liu, Zhen
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.17 no.3
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    • pp.182-188
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    • 2014
  • In an oscillating water column (OWC)-type wave energy conversion system, the performance of the OWC chamber depends on the chamber shape, as well as the incident wave direction and pressure drop produced by the turbine. Although the previous studies on OWC chambers have focused on wave absorbing performance in ideal operating conditions, incident waves do not always arrive normally to the OWC chamber in real sea conditions, especially in fixed devices. The present study deals with experiments and numerical calculations to investigate the effects of wave direction on the performance of the OWC chamber. The experiments were carried out in a three-dimensional wave basin for five different wave directions, including the effect of turbine using the corresponding orifice. The wave elevation inside the chamber was measured at the center point under various incident wave conditions. The numerical study was conducted by using a numerical wave tank-based volume-of-fluid model to compare the results with experimental data and to reveal the detailed flows around the chamber.

Analysis of Reliability of Weather Fields for Typhoon Maemi (0314) (태풍 기상장의 신뢰도 분석: 태풍 매미(0314))

  • Yoon, Sung Bum;Jeong, Weon Mu;Jho, Myeong Hwan;Ryu, Kyong Ho
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.32 no.5
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    • pp.351-362
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    • 2020
  • Numerical simulations of the storm surge and waves induced by the Typhoon Maemi incident on the south sea of Korea in 2003 are performed using the JMA-MSM forecast weather field, NCEP-CFSR reanalysis weather field, ECMWF-ERA5 reanalysis weather field, and the pressure and wind fields obtained using the best track information provided by JTWC. The calculated surge heights are compared with the time history observed at harbours along the coasts of Korea. For the waves occurring coincidentally with the storm surges the calculated significant wave heights are compared with the measured data. Based on the comparison of surge and wave heights the assessment of the reliability of various weather fields is performed. As a result the JMA-MSM weather fields gives the highest reliability, and the weather field obtained using JTWC best track information gives also relatively good agreement. The ECMWF-ERA5 gives in general surge and wave heights weaker than the measured. The reliability of NCEP-CFSR turns out to be the worst for this special case of Typhoon Maemi. Based on the results of this study it is found that the reliable weather fields are essential for the accurate simulation of storm surges and waves.

Motility and Chemotaxis in the Lyme Spirochete Borrelia burgdorferi: Role in Pathogenesis (라임병 원인 스피로헤타 Borrelia burgdorferi의 운동성과 주화성: 발병기전에서의 역할)

  • Yoo, Ah Young;Kang, Ho Young;Moon, Ki Hwan
    • Journal of Life Science
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    • v.28 no.5
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    • pp.627-637
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    • 2018
  • Motility and chemotaxis are crucial for disease development in many motile pathogens, including spirochetes. In many bacteria, motility is provided by flagella rotation, which is controlled by a chemotaxis-signal-transduction system. Thus, motility and chemotaxis are inextricably linked. Spirochetes are a unique group of bacteria with distinctive flat-wave morphology and corkscrew-like locomotion. This unusual motility pattern is believed to be important for efficient motility within the dense tissues through which these spirochetes preferentially disseminate in a host. Unlike other externally flagellated bacteria-where flagella are in the ambient environment-the flagella of spirochetes are enclosed by the outer membrane and thus are called periplasmic flagella or endoflagella. Although motilityand chemotaxis-associated genes are well studied in some bacteria, the knowledge of how the spirochete achieves complex swimming and the roles of most of the putative spirochetal chemotaxis proteins are still elusive. Recently, cutting-edge imaging methods and unique genetic manipulations in spirochetes have helped to unravel the mystery of motility and chemotaxis in spirochetes. These contemporary advances in understanding the motility and chemotaxis of spirochetes in a host's persistence and disease process are highlighted in this review.