• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.3 s.55
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• pp.135-144
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• 2009

The cable system of suspension bridges is a very important non-elastic element which caries an external load by a tension force of the cable, such that creates the integrity of a structure. It is not easy to find if cable system have been changed by the maintenance activities such as repairs or reinforcement. Sometimes the maintenance can cause structural deformations and changes of the tension force in cables. In most cases, the cable stayed bridges are managed by health monitering system, however, the main cable of suspension bridges need to develop more accurate and efficient monitoring system. The Namhee Bridge was constructed 35 years ago and it has been continually repaired and reinforced after then. This study describes the behavior of the cable system by analysing many of inspective reports and by using the results of hanger rope test and for the shape of main cables surveys.

• Korean Journal of Plant Taxonomy
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• v.48 no.4
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• pp.249-259
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• 2018

$Iso{\ddot{e}}tes$ L. ($Iso{\ddot{e}}taceae$) is a cosmopolitan genus of heterosporous lycopods containing ca. 200 species being found in lakes, streams, and wetlands of terrestrial habitats. Despite its ancient origin, worldwide distribution, and adaptation to diverse environment, species in $Iso{\ddot{e}}tes$ show remarkable morphological simplicity and convergence. Allopolyploidy appears to be a significant speciation process in the genus. These characteristics have made it difficult to assess the phylogenetic relationships and biogeographic history of $Iso{\ddot{e}}tes$ species. In recent years, these difficulties have somewhat been reduced by employing multiple molecular markers. Here, we reconstruct the phylogenetic relationships in East Asian $Iso{\ddot{e}}tes$ species. We also provide their divergence time and biogeographic origin using a fossil calibrated chronogram. East Asian $Iso{\ddot{e}}tes$ species are divided into two clades: I. asiatica and the remaining species. $Iso{\ddot{e}}tes$ asiatica from Hokkaido forms a clade with northeastern Russian and western North American $Iso{\ddot{e}}tes$ species. In clade I, western North America is the source area for the dispersal of $Iso{\ddot{e}}tes$ to Hokkaido and northeastern Russia via the Bering land bridge during the late Miocene. The remaining $Iso{\ddot{e}}tes$ species (I. sinensis, I. yunguiensis, I. hypsophila, I. orientalis, I. japonica, I. coreana, I. taiwanensis, I. jejuensis, I. hallasanensis) from East Asia form a sister group to Papua New Guinean and Australian species. The biogeographic reconstruction suggests an Australian origin for the East Asian species that arose through long-distance dispersal during the late Oligocene.

• Korean Journal of Plant Taxonomy
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• v.43 no.1
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• pp.34-45
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• 2013

The Polygonum amphibium complex (Poygonaceae) is a highly polymorphic taxon that can grow in aquatic environments as well as in moist terrestrial habitats. Aquatic and terrestrial plants of the P. amphibium complex vary significantly in morphology and exhibit very complicated patterns of morphological variation, resulting in the description of numerous infra-specific taxa. Principal components analysis of 107 individuals of the P. amphibium complex from Asia and North America using 11 morphological characters showed that the aquatic plants can be discerned from the terrestrial plants by leaf size, shape, and petiole length. In contrast, both aquatic and terrestrial plants collected from the same population or locality shared identical sequences in the matK, psbA-trnH IGS, rbcL-accD IGS and trnL-trnF regions of the chloroplast DNA (cpDNA), suggesting that aquatic and terrestrial forms of the P. amphibium complex are not genetically diverged; morphological differences between the two forms are probably due to the differences in environmental conditions of the habitats. In addition, results from the morphological analysis and the maximum parsimony analysis of the cpDNA data set revealed that the plants from Asia including Korea, Japan, China, Mongolia and Russia Far East are diverged from those in North America and Europe, suggesting that the Asian populations should be recognized as a distinct variety, P. amphibium var. amurense Korsh.

• Korean Journal of Environmental Biology
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• v.35 no.2
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• pp.160-168
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• 2017

Tscherskia triton is widely distributed in Northern China, Korea, and the adjacent areas of Russia. Except its distribution, reproduction, and growth development related to life history, reproductive cycle and reproductive organs of T. triton are rarely studied in Korea. The purpose of this study was characterized the estrous cycle of T. triton captured in Jeju Island in order to provide information to a better information of captive breeding of the species when long-day (16L : 8D) and short-day (8L : 16D) photoperiod. Then, histological study of the ovaries and uterus with five females in each photoperiod was performed. The duration of the estrus cycle was 4~5 days and it showed regular cycle pattern. Results of the vaginal cytology examination showed four characteristic phase of the estrous cycle in long-day photoperiod (16L : 8D): proestrus, estrus, metestrus and diestrus. However, in short-day photoperiod, the diestrus phage of the estrus cycle was maintained from the $6^{th}$ to $12^{th}$ day. In the long-day photoperiod, females had many Graafian follicles and corpus luteums in large ovaries, and developed uterine glands in the thick endometrium. But they had some primary, secondary and tertiary follicles, and undeveloped uterine glands in the thin endometrium during short-day photoperiod. These results were identified difference of the estrus cycle and histological characteristics of reproductive tracts according to the photoperiod. These results are very important clues to the reproductive biology of T. triton, and it will be widely used as date for maintaining biodiversity.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.1
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• pp.25-33
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• 2015

The Strait of Malacca is one of the most important fairways in the world and its traffic safety has direct effect on economic development of East Asian countries including China, Japan and Korea. Because of this reason, a safety analysis of the marine traffic in the strait has a great significance. In this paper, we analysed the statistic distribution of marine traffic in the Strait of Malacca based on the vessels' AIS data for 1 month by using the TOAIS and EasyFit programs. As the results of the analysis, it was found that the traffic distribution of this strait was different with normal distribution, which had been still widely used in marine traffic engineering field. Furthermore, with the traffic distribution analysis results, the traffic safety of the strait was also assessed by using the IWRAP model. The results showed that the highest level of risk were overtaking and crossing situations. Finally, we found that the highest risk of collision area in the Strait of Malacca was crossing area between the Strait of Malacca and the Port Klang fairway.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.4
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• pp.875-886
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• 2015

By promoting the international transportation and the improvement of advanced exchange between South and North Korea, the Asian Highway plan was expected to make considerable economical effects in the North-East Asian region. This study focuses on a part of AH6 route (i.e., South Korea-North Korea-China-Far East Russia) and aims to analyze the behavioral change of international passenger transport around the Korean Peninsula by assuming the non-existent North Korea land transport network connectivity. The study was performed using two main methods. First, a stated preference survey was performed to derive the actual modal share of each travel mode. Second, a disaggregate analysis was performed to develop possible mode-choice models for international passenger travel and find out the suitable choice. Based on the results of the model estimation, it is found that over 90% of the international passenger transport would be converted to land transport (rail+highway). In addition, international railroad modal share rate would be increased from 62.8% to 66.1% and international bus would be decreased from 29.6% to 21.9% as the distance lengthened (903km~1,631km).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.6
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• pp.463-467
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• 2004

This study was carried out to estimate of leaf area index (LAI) rapidly using plant canopy analyzer, comparing with specific leaf area (SLA) and leaf area ratio (LAR) in rice from 2001 to 2002 at Honam Agricultural Research Institute in Iksan Korea. The relationship between LAI values taken by plant canopy analyzer and by leaf area meter showed high correlation at each growth stages of rice. LAIs obtained by plant canopy analyzer were highly correlated with that by leaf area meter which were the highest in Dongjinbyeo and the lowest in Hapcheon1. Specific leaf area (SLA) of all rice cultivars were tend to decrease remarkably with the progress of growth stage. It was found that the SLA of Dasanbyeo was the highest and that of Hapcheon1 was the lowest among rice cultivars tested. Leaf area ratios (LARs) was also decreased with the progress of growth stage.

• Korean Security Journal
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• no.50
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• pp.145-172
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• 2017

In 2015 the Department of Education announced that it will make downsizing efforts by recommending classified downsizing ratio according to the evaluation of universities for active support toward autonomous efforts of universities with the possibilities of reform and qualitative structural reform for customized human resource cultivation according to the social demands. This is the preemtive structural reform preparing against the rapid decrease of the number of students, and the preparation for changing into competitive universities so that customized human resource that is needed in the society can be trained. Security Science Departments of Korea, first established in 1996, need changes in curriculum in order to prepare for the fourth revolution of the future, and are stagnant on the education goal and employment course. Therefore the adoption of related certificates, curriculum, NCS, and professional curriculum is needed. For example, Hansei University, Chung-Ang University, and Far East University have established the Department of Industrial Security, and Kyonggi University and Sungshin Women's University have established the Department of Convergence Security. Also, Konkuk University has established the Graduate School of Security and Disasters, the Graduate School of Information and Policy, the Graduate School of Criminal Justice, Gachon University the Graduate School of National Security, Sungkyunkwan University the Graduate School of Strategic Studies. This shows that the field of Security Science should not settle for itself. This article analyzes current curriculum and subjects of security, police, industrial security, military related academic departments of key universities. It is necessary to prepare for the future by predicting the change from the merge of academic departments and the demands of the times. As technical colleges are adopting NCS, this is the time to seek for systematic collaboration between universities and technical colleges and between industry, government, and academida.

• Korean Journal of Microbiology
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• v.49 no.1
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• pp.17-23
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• 2013

Candida biofilms are organized microbial communities growing on the surfaces of host tissues or indwelling medical devices, and the biofilms show enhanced resistance against the conventional antifungal agents. The roots of Coptidis chinensis have been widely used for medicinal purposes in East Asia. The present study was aimed to assess the effect of C. chinensis aqueous extract upon preformed biofilms of 10 clinical Candida albicans isolates and the antifungal activities which contribute to inhibit the C. albicans biofilm formation. Its effect on preformed biofilms was judged using XTT [2,3-Bis-(2-Methoxy-4-Nitro-5-Sulfophenyl)-2H-Tetrazolium-5-Carboxanilide)] reduction assay, and metabolic activity of all tested strains was reduced significantly ($57.3{\pm}14.7%$) at $98{\mu}g/ml$ of the C. chinensis extract. The extract damaged the cell membrane of C. albicans which was analyzed by fluorescein diacetate and propidium iodide staining. The anticandidal activity was fungicidal, and the extract obstructed the adhesion of C. albicans biofilms to polystyrene surfaces, arrested C. albicans cells at $G_o/G_1$ as well, and reduced the growth of biofilms or budding yeasts finally. The data suggest that C. chinensis has multiple antifungal effects on target fungi resulting in preventing the formation of biofilms. Therefore, C. chinensis holds great promise for exploring antifungal agents from natural products in treating and eliminating biofilm-associated Candida infection.

• Journal of Korean Society of Forest Science
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• v.98 no.3
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• pp.279-283
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• 2009

This study was conducted to clarify the breeding bird communities between natural and fired forests in Verchneussuriisky Research Forest ($44^{\circ}$ 02' N, $134^{\circ}$ 10' E) Institute of Biology and Soil Science, Far-East Branch, Russian Academy of Science at Ussuri, Russia from 7 to 11 June 2008. Total 37 species of birds were recorded in both study sites. Luscinia cyane, Urosphena squameiceps, and Emberiza tristrami were most dominant species. In natural forest, 115 individuals of 32 species were observed and bird species diversity (H') was 3.13. Sixty two individuals of 29 species were recorded and bird species diversity was 3.12 in fired forest. Bush and Canopy nesting guilds were higher in natural forest than in fired forest. But hole nesting guild was higher in fired forest. In foraging guilds, canopy foraging guild was most dominant in both study site. Air and bush foraging guilds were higher in natural forest. The differences of bird communities would be caused by differences of habitat conditions between study sites.