• Journal of the Korean Society for Railway
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• v.8 no.4
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• pp.337-341
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• 2005

Algorithm for passenger flow analysis based on DEM(Discrete Element Method) is newly developed. In the new algorithm, there are many similarity between multi phase flow and passenger flow. The velocity component of 1st phase corresponds to the direction vector of cell, each particle to each passenger, volume fraction to population density and the momentum equation of particle to the walking velocity equation of passenger, etc. And, the walking velocity of passenger is also represented by the function of population density. Key algorithms are developed to determine the position of passenger, population density and numbering to each passenger, To verify the effectiveness of new algorithm, passenger flow analysis for simple railway station model is conducted. The results for passenger flow in the model station are satisfying qualitatively and quantitatively.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.387-391
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• 2006

Insight into behaviour of pedestrians as well as tools to assess passenger flow conditions are important in for instance planning and geometric design of railway station under regular and safety-critical circumstances. Algorithm for passenger flow analysis based on DEM(Discrete Element Method) is newly developed. There are lots of similarity between particle-laden two phase flow and passenger flow. The velocity component of 1st phase corresponds to the unit vector of calculation cell, each particle to passenger, volume fraction to population density and the particle velocity to the walking velocity, etc. And, the walking velocity of passenger is also represented by the function of population density. Key algorithms are developed to determine the position of passenger, population density and numbering to each passenger. To verify the effectiveness of new algorithm, passenger flow analysis for the basic models of railway station is conducted.

• Korean Journal of Weed Science
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• v.13 no.2
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• pp.159-163
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• 1993

This research was conducted at the Crop Experiment Station to determine the changes of weed flora under direct seeded rice cultivation in dry paddy field from 1989 to 1992 and to establish an effective weed control strategy in direct seeded rice cultivation. With the continuous rice growing under direct seeded rice cultivation in dry paddy field, there were more occurrence in grasses and annual weeds while broadleaf and perennial weeds were diminished. The predominant weeds were aquatic weeds such as Eleocharis kuroguwai, Echinochloa crusgalli, and Monochoria vaginalis in machine transplanted rice paddy field while there were predominant of semi aquatic weed species such as E. crusgalli, Digitaria sanguinalis, Bidens tripartita, Aeschynomene indica, and Arthraxon hispidus in continuous direct seeded rice cultivation in dry paddy condition. Based on the vegetative analysis of weeds in terms of simpson index and community dominance, there was more distribution of weed species in direct seeded rice cultivation on dry paddy condition while only distributed with 1-2 weed species in machine transplanted rice paddy field. In similarity coefficient, there was a gradual increase up to 67% of weeds with the continuous direct seeded rice cultivation in dry paddy condition for 4 years starting from 41% of similarity coefficient.

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.250-257
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• 2008

Knowledge of genetic diversity and of the genetic relationships among elite breeding materials has had a significant impact on the improvement of crops. In maize, this information is particularly useful in i) planning crosses for hybrid and line development, ii) in assigning lines to heterotic groups and iii) in plant variety protection. We have used the SSR technique to study the genetic diversity and genetic relationships among 76 Korean waxy corn accessions, representing a diverse collection from throughout Korea. Assessment of genetic diversity among members of this group was conducted using 30 microsatellite markers. Among these 30 microsatellite markers, we identified a total of 127 alleles (with an average of 4.2 and a range of between 2 and 9 alleles per locus). Gene diversity at these 30 microsatellite loci varied from 0.125 to 0.795 with an average of 0.507. The cluster tree generated with the described microsatellite markers recognized two major groups with 36.5% genetic similarity. Group I includes 63 inbred lines, with similarity coefficients of between 0.365 and 0.99. Group II includes 13 inbred lines, with similarity coefficients of between 0.45 and 0.85. The present study indicates that the 30 microsatellite loci chosen for this analysis are effective molecular markers for the assessment of genetic diversity and genetic relationships between Korean waxy corn accessions. Specifically, this study's assessment of genetic diversity and relationships between a set of 76 Korean waxy corn inbred lines will be helpful for such activities as planning crosses for hybrid and line development and association mapping analyses of maize breeding programs in Korea.

• Ocean and Polar Research
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• v.36 no.4
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• pp.423-435
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• 2014

Verifying the similarity of environmental characteristics between an artificial impact site and a preserved or reference site is necessary to quantitatively and qualitatively evaluate the environmental impact of mining activity. Although an impact site (BIS station) and a preserved site (called KOMO station) that have been selected in the Korea manganese nodule contract area may share similar environmental characteristics, similarities in terms of the water column environment between both sites has not been investigated. In this study, we compared the chemical properties of the water columns and sinking particle fluxes between BIS and KOMO stations through two observations (August 2011 and September 2012). Additionally, we observed particle fluxes at the KOMO station for five years (July 2003~July 2008) to understand long-term natural variability. Vertical distributions of water column properties such as dissolved oxygen, inorganic nutrients (N, P, Si), total organic carbon below surface layer (within the depth range of 200 m) were not considerably different between the two sites. Especially, values of water column parameters in the abyssopelagic zone from 4000 m to bottom layer (~5000 m) were very similar between the BIS and KOMO sites. Sinking particle fluxes from the two sites also showed similar seasonality. However, natural variation of particle flux at the KOMO site varied from 3.5 to $129.9mg\;m^{-2}day^{-1}$, with a distinct temporal variation originating from ENSO events (almost forty times higher than a minimum value). These results could provide valuable information to more exactly evaluate the environmental impact of mining activity on water columns.

• Journal of Plant Biotechnology
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• v.43 no.1
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• pp.49-57
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• 2016

We isolated and confirmed two S-RNases, denoted as mpS1 and mpS2, from apple rootstock 'Marubakaido' (Malus prunifolia Borkh. Var. ringo Asami). These S-RNases contained and conserved five cysteine residues and two histidine residues, which are essential for RNase activity. The mpS1 showed high similarity to S5 (99.1%) of Malus spectabilis, whereas the mpS2 showed 99.5% nucleotide sequence similarity to S26 of (Malus ${\times}$ domestica) and 99.6% to S35 of (Malus sieversii) when compared with reported S-RNases. In amino acid sequences, the mpS1-RNase was almost similar to the S5-RNase of Malus spectabilis, and the mpS2-RNase was similar to the S35 of Malus sieversii, with only one bp being different from the S26-RNase of Malus ${\times}$ domestica. The 57 S-RNases of Malus species were renamed and rearranged containing the new S-RNases, as mprpS35 (mpS2) and mprpS57 (mpS1), for determining S-genotypes and identifying new alleles from apple species (Malus spp.).

• Journal of Plant Biotechnology
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• v.3 no.3
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• pp.145-149
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• 2001

This study was conducted to analyze the morphological characteristics such as flower color, flower type, flower diameter and flower stalk, and the main annual production yield, and genetic similarity of twenty four Gerbera species growing in Korea. Most of flower colors were pink. The numerical order of flower color was pink, orange, red, double-colored, and milk-white. Majority of flower types were sin81e or semidouble flowers. A few species were double flowers. flower diameters were from 7 ㎝ to 12 ㎝, showed significant differences compared to other characteristics. Flower stalks were ranged from 55 ㎝ to 65 ㎝. Only one species was the shortest as 55 ㎝. The others were similar size as about 65 ㎝. Main annual production yields were between 190 and 400 blossoms. Fifty seven reproducible polymorphic bands from eighty primers were used for analyses of genetic similarity. The genetic similarity of 24 collected Gerberas was largely classified into five groups. The average similarity coefficient was 0.72 ranged from 0.50 to 0.90. The highest similarity coefficient was shown between 'Sardana' with red/white flower color and double flower type, and 'Tamara' with orange flower color and double flower type as 0.90.

• Journal of Forest and Environmental Science
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• v.38 no.2
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• pp.75-89
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• 2022

The negative impact of monoculture rubber plantations on biodiversity and associated ecological processes/ecosystem services has led to suggestions on the use of integrated land use systems for rubber cultivation and production in order to ensure environmental sustainability. However, there is paucity of information on the effect of such integrated land use systems on the diversity and abundance of the rubber plantation undergrowth. We evaluated and compared undergrowth plant species composition, richness, abundance, diversity and interaction, in three integrated systems (Rubber-Strelitzia reginae Integrated System - RSrIS, Rubber-Podocarpus nagi Integrated System - RPnIS & Naturally Managed Rubber Plantation - NMRP) with three Rubber Monoculture Plantations (RMP₁, RMP₂ & RMP₃) adjacent to the integrated systems, respectively, at the Investigation and Experiment Station of Tropical Crops, Danzhou, Hainan, China. Undergrowth species density was higher in the rubber monocultures than in the integrated systems except in RSrIS. Species richness and diversity were also higher in the monocultures except in NMRP. Species similarity/interaction between the monocultures and the integrated systems was highest between RMP₃ and NMRP. The NRMP proved to be the best model of natural rubber integrated system for the conservation of undergrowth species richness, diversity and interspecific interaction. However, the conservation of undergrowth species in other forms of integrated natural systems can be enhanced by considering the ecology of species to be integrated in terms of their growth characteristics, competitive nature, and ability to grow in association with other species.

• Journal of Environmental Science International
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• v.7 no.5
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• pp.607-613
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• 1998

This study was carried out to investigate flora of phytoplankton in Milyang River from July 1996 to April 1997. Phytoplankton were identified 206 kinds and composed of 2 var.-for., 5 forms, 35 varieties, 164 species, 70 genera, 31 families, 14 orders, 6 classes and 5 phyla. According to the seasonal variation, 131 species were founded in summer, 109 species in spring, 108 species in autumn, and 100 species in winter, respectively. Seasonal and stationary variation of standing crops were between 10 and 5.600 cells/mι. At station 7, Cyclotella meneghiniana was bloomed 5,000 cells/mι(89.7%) in winter, and Stephanodiscus hantzschii was bloomed 3,400 cells/mι(74.3%) in spring. The number of species and standing crops were increased with proceeding from upper stream to lower stream. Important species of phytoplankton were 24 species, that are 4 species of Cyanophyta (Aphanocapsa elachista, Merismopedium glaucum, Lyngbya limnetica, Oscillatoria tenuis), 12 species of Crysophyta (Melosira varians, Stephanodiscus hantzschii, Cyclotalla meneghiniana, Fragilaria construens var. venter, Navicula cryptocephala, Cymbella ventricosa, Gomphonema olivaceum), and 8 species of Chlorophyta (Chlamydomonas reinhardi, Eudorina elegans, Pandorina morum, Oocystis borgei, Scenedesmus quadricauda, Microspora crassior). According to the similarity index among the stations, it was generally defind as two water areas such as upper stream(station 1~3) and lower stream(station 4~7).

• Korean Journal of Medicinal Crop Science
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• v.8 no.2
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• pp.102-108
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• 2000

Morphological characteristics of nine Epimedium spp was analyzed on the basis of six morphological characters. To analyse the genetic relationship among Epimedium spp., polymerase chain reaction (PCR) was performed with total genomic DNA of 17 Epimedium spp. by using random 8 primers. The genetic diversity and genetic distance among nine Korean collections, seven Japanese and one China collection were used to generate a dendrogram showing phylogenie relationship. Seventeen Epimedium spp were classified into two groups of group I and II, since they were divided into two major groups at the similarity coefficients value of 0.65. In addition, one of the two group, group I was divided into three sub-groups including Epimedium koreanum, Chul-won collections 1, 2, and 3, Yanggu, Hongchon, Hwachun, Chunchon, China, Maehwa (Japanese), E. diphyllum and E. violaceum (Japanese), while group II included Chulwon collection 4 and 5 and Japanese collection. The samples collected at Chulwon district showed close similarity with Japanese collection. Similarity indexes between collection and genetic relationship were related at the levels ranging from 0.6 to 0.9.