• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.1
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• pp.50-56
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• 2011

To make conservative port and coast ecosystems and creative the greenspace, We were investigated with characteristic of flora, environmental factors, types of port, adaptive species, minimum conservation area and plantation model. In 50 sites of study areas, there are 19 families and 174 species of vascular plants and 19 families and 48 species of halophytes. Dominant communities in port ecosystem contains Carex kobomugi community, Elymus mollis community, Carex pumila community, Ixeris repens community, Vitex rutundifolia community, Calystegia soldandlla community, Rosa rugosa community, Lathyrus japonica community, Salsola komarovi community, Cynodon dactylon community, Tetragonia tetragonioides community, Suaeda japonica community, Suaeda maritima community, Zoysia sinica community and Phragmites communis community. We carried out Canonical Correspondence Analysis(CCA) for ordinations on the vegetation and plant communities-environmental variable matrices in 50 sites. The communities tended to cluster into three types: Clay marsh, Sand marsh, Sand gravel marsh types. Adaptive species in habitate types are selected that sand marsh-type communities in ports contained Elymus mollis community, Ixeris repens community, Carex kobomugi community, Carex pumila community, Clay marsh-type communities contained Suaeda japonica community, Phragmites communis community, Zoysia sinica community and Suaeda maritima community, Sand gravel marsh-type communities contained Vitex rutundifolia community, Calystegia soldandlla community. We are conducted the estimation of minimal area for plantation of adaptive plant species and carried out guide line and plantation model for creation of green space in port ecosystem.

• Korean Journal of Environment and Ecology
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• v.25 no.1
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• pp.10-16
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• 2011

This study was carried out to analyze the vegetation and soil characteristic, and ordination of the Ilex cornuta population, in the Yongsu Reservoir of Jeju Island. The Ilex cornuta population was classified into Cudrania tricuspidata dominant population, Sageretia theezans dominant population, and Mallotus japonicus dominant population. In the study sites, soil organic matter(O.M.), total nitrogen(T.N.), available phosphorus($P_2O_5$), changeable potassium, changeable calcium, changeable magnesium and soil pH were 14.62~17.35%, 0.39~0.51%, 8.83~20.15mg/kg, 0.44~0.64cmol+/kg, 5.79~6.87cmol+/kg, 3.43~4.19cmol+/kg and 5.41~5.80, respectively. The Mallotus japonicus dominant population was mainly found in the high percentage of available phosphorus, organic matter. It was also showed the lowest concentration of exchangeable K, and Mg. Cudrania tricuspidata dominant population and Sageretia theezans dominant population were found in the low percentage of available phosphorus, organic matter and there were also showed the highest concentration of exchangeable K, and Mg. It is one of the evidence that Ilex cornuta community indicated an intensive site management likes clearance of creeper is proper habitat management protocol. Thus, further researches should be followed to determine the other disturbance factors as management techniques.

• International Journal of High-Rise Buildings
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• v.1 no.1
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• pp.37-51
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• 2012

New generation of tall and complex buildings systems are now introduced that are reflective of the latest development in materials, design, sustainability, construction, and IT technologies. While the complexity in design is being overcome by the availability and advances in structural analysis tools and readily advanced software, the design of these buildings are still reliant on minimum code requirements that yet to be validated in full scale. The involvement of the author in the design and construction planning of Burj Khalifa since its inception until its completion prompted the author to conceptually develop an extensive survey and real-time structural health monitoring program to validate all the fundamental assumptions mad for the design and construction planning of the tower. The Burj Khalifa Project is the tallest structure ever built by man; the tower is 828 meters tall and comprises of 162 floors above grade and 3 basement levels. Early integration of aerodynamic shaping and wind engineering played a major role in the architectural massing and design of this multi-use tower, where mitigating and taming the dynamic wind effects was one of the most important design criteria established at the onset of the project design. Understanding the structural and foundation system behaviors of the tower are the key fundamental drivers for the development and execution of a state-of-the-art survey and structural health monitoring (SHM) programs. Therefore, the focus of this paper is to discuss the execution of the survey and real-time structural health monitoring programs to confirm the structural behavioral response of the tower during construction stage and during its service life; the monitoring programs included 1) monitoring the tower's foundation system, 2) monitoring the foundation settlement, 3) measuring the strains of the tower vertical elements, 4) measuring the wall and column vertical shortening due to elastic, shrinkage and creep effects, 5) measuring the lateral displacement of the tower under its own gravity loads (including asymmetrical effects) resulting from immediate elastic and long term creep effects, 6) measuring the building lateral movements and dynamic characteristic in real time during construction, 7) measuring the building displacements, accelerations, dynamic characteristics, and structural behavior in real time under building permanent conditions, 8) and monitoring the Pinnacle dynamic behavior and fatigue characteristics. This extensive SHM program has resulted in extensive insight into the structural response of the tower, allowed control the construction process, allowed for the evaluation of the structural response in effective and immediate manner and it allowed for immediate correlation between the measured and the predicted behavior. The survey and SHM programs developed for Burj Khalifa will with no doubt pioneer the use of new survey techniques and the execution of new SHM program concepts as part of the fundamental design of building structures. Moreover, this survey and SHM programs will be benchmarked as a model for the development of future generation of SHM programs for all critical and essential facilities, however, but with much improved devices and technologies, which are now being considered by the author for another tall and complex building development, that is presently under construction.

• Journal of Korean Society of Forest Science
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• v.107 no.2
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• pp.151-157
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• 2018

This study was to analyze the genetic diversity of Quercus gilva Blume growing in Jeju Island for developing a preservation strategy. We examined the genetic diversity and structure using 6 ISSR primers and investigated 67 polymorphic ISSR amplicons in 80 trees distributed among five populations. The average of proportion of polymorphic loci were 93%, the average level of Shannon's information index was 0.237, and Nei's genetic diversity was 0.156. According to the analysis of the molecular variance (AMOVA), $F_{st}$ was 0.169 indicating there was a genetic variation among five populations. 17% of the total variation was allocated among the five populations, while the other 83% of the total variation was in individual trees in each population. The result could be due to the uneven number of trees among the five populations. Based on these results, the preservation strategy could be developed, for examples, considering for designation as "forest genetic resources conservation area" about the habitat, monitoring continuously, fostering the growth of seedling, ex situ preservation of genetic resources, and comparing the differences of environmental and genetic characteristic with population in ex situ.

• Korean Journal of Plant Taxonomy
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• v.39 no.1
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• pp.29-34
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• 2009

The Chrysanthemum zawadskii complex is demarcated from other species by having the white and pink ligulate flowers. Its morphological characters are greatly diversified, so that various classification systems have been suggested. The character of leaf thickness has been mentioned as the characteristic for recognizing some of infra-specific taxa within this complex. In this study, we used longitudinal leaf sections to investigate the leaf thickness and cell number of leaf blades of 13 populations including those of the members of the C. zawadskii complex, as well as 4 populations of the related species of C. boreale and C. indicum. From the result, it was clear that the leaves were thicker in populations of C. boreale, C. indicum and C. zawadskii complex (diminishing in that order), and that the leaves were composed of about 9 cell layers in all populations. Within the C. zawadskii complex, leaf shape and thickness varied among the populations. It was very interesting that the taxa with restricted distribution, like C. zawadskii var. tenuisectum, C. zawadskii var. alpinum, C. zawadskii var. lucidum, and C. zawadskii subsp. coreanum had a thicker leaves than found among widely occurring taxa. From this, leaf thickness is supposed to be an adaptation to the unique habitat of each population.

• Korean Journal of Environment and Ecology
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• v.27 no.5
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• pp.625-641
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• 2013

This study is analyzed the environmental ecological status of Suncheon Bay and its applicable possibility to the selection criteria of UNESCO World Natural Heritage (hereafter Criteria). The study shows that the formation process of the tidal-flats in Suncheon bay could apply to the Criteria VIII, "to be outstanding examples representing major stages of earth's history." The landscape pattern of Suncheon Bay is deduced various patterns based on 5 biotope types: tidal-flat, rice-paddy, field area, coniferous natural forest, and broadleaf natural forest. Its landscape characteristic is a harmonized composition of various landscape including mountains, rivers, fields, and tidal-flats. It is judged that the unique landscape of Suncheon Bay falls under the criteria VII, "areas of exceptional natural beauty and aesthetic importance." In addition, Suncheon Bay, the habitat of the Hooded Crane as internationally endangered species, comes under the criteria X, "the most important and significant natural habitats for in-situ conservation of threatened species." The study shows, however, that any other designation for protected area including national park or biosphere reserve is a prerequisite for designation of World Nature Heritage. In particular, it could evaluate whether it is qualified of the Criteria after the integrated conservation and management to the Sucheon bay as well as the southwestern tidal-flat is preceded.

• Korean Journal of Environmental Agriculture
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• v.27 no.1
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• pp.72-79
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• 2008

Phytosociological study was carried out to investigate the structural characteristics of Humulus japonicus community in the Middle area of Korea. The vegetation data of total 67 $relev\acute{e}s$ were analyzed by the $Z\ddot{u}rich$-Montpellier school's method. Upper layer plant communities of Humulus japonicus were classified into four community groups : Humulus japonicus-Artemisia princeps community, Chenopodium album community, Setaria viridis-Echinochloa crus-galli community and Typical community. Lower layer plant communities were classified into five community groups : Galium spurium-Stellaria aquatica community, Equisetum arvense community, Persicaria theunbergii community, Echinochloa crus-galli-Digitaria ciliaris community and Typical community. According to the results of canonical correspondence analysis by vegetation and environmental factor, Setaria viridis-Echinochloa crus-galli community of upper layer was distributed throughout the soil with high relative light and soil hardness. Chenopodium album community appeared in the soil with high pH. Galium spurium-Stellaria aquatica community of lower layer was formed in the high soil pH. Persicaria theunbergii community and Echinochloa crus-galli-Digitaria ciliaris community were distributed in the soil with high moisture.

• Korean Journal of Ecology and Environment
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• v.47 no.spc
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• pp.10-18
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• 2014

The habitat characteristic of the Gammarus sobaegensis which is one of the Amphipoda kinds has been found inhabiting in the inter mountain stream at Ganseong stream. From the investigation, the main inhabitant area of the G. sobaegensis maintained the water temperature under $10^{\circ}C$ during the spring and autumn season, and the electric conductivity was also maintaining under $40{\mu}Scm^{-1}$. For the precipitation, for this year when the monthly accredited rainfall did not exceed 800 mm, it did not affect maintaining the population of the G. sobaegensis but when the monthly accredited rainfall exceeded 1,000 mm it was found to be working as a unfavorable condition for maintaining the population. The effect especially from this kind of rainfall created the flow of G. sobaegensis as well as the flow of the fallen leaves which are the food resources and affected the population of the G. sobaegensis as a multiple interruption reason. Among the Functional Feeding Groups (FFGs) distribution depending on the use of the food resources the shredders showed up in the ratio of 20% in the site 1~3, and showed a big difference with the site 4~7 as it showed up in the ratio near 10%. Also, after comparing the variation of the individual number among the G. sobaegensis and shredders at the site 1~3 where G. sobaegensis mainly shows up, it showed the same variation pattern except for 2009.

• International Journal of High-Rise Buildings
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• v.10 no.4
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• pp.345-364
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• 2021

Developments in the understanding of fire behaviour for large open-plan spaces typical of tall buildings have been greatly outpaced by the rate at which these buildings are being constructed and their characteristics changed. Numerous high-profile fire-induced failures have highlighted the inadequacy of existing tools and standards for fire engineering when applied to highly-optimised modern tall buildings. With the continued increase in height and complexity of tall buildings, the risk to the occupants from fire-induced structural collapse increases, thus understanding the performance of complex structural systems under fire exposure is imperative. Therefore, an accurate representation of the design fire for open-plan compartments is required for the purposes of design. This will allow for knowledge-driven, quantifiable factors of safety to be used in the design of highly optimised modern tall buildings. In this paper, we review the state-of-the-art experimental research on large open-plan compartment fires from the past three decades. We have assimilated results collected from 37 large-scale compartment fire experiments of the open-plan type conducted from 1993 to 2019, covering a range of compartment and fuel characteristics. Spatial and temporal distributions of the heat fluxes imposed on compartment ceilings are estimated from the data. The complexity of the compartment fire dynamics is highlighted by the large differences in the data collected, which currently complicates the development of engineering tools based on physical models. Despite the large variability, this analysis shows that the orders of magnitude of the thermal exposure are defined by the ratio of flame spread and burnout front velocities (V_S / V_BO), which enables the grouping of open-plan compartment fires into three distinct modes of fire spread. Each mode is found to exhibit a characteristic order of magnitude and temporal distribution of thermal exposure. The results show that the magnitude of the thermal exposure for each mode are not consistent with existing performance-based design models, nevertheless, our analysis offers a new pathway for defining thermal exposure from realistic fire scenarios in large open-plan compartments.

• Korean Journal of Plant Resources
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• v.34 no.1
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• pp.44-51
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• 2021

Centella asiatica (L.) Urban is a medicinal plant containing madecassic acid, triterpenoids and asiaticoside, and has a wound healing effect. However, since it grows only in some regions of Korea, it is necessary to breed stable varieties. In this study, it were analyzed for the growth characteristics, asiaticoside, anxiodant components and 2,2-diphenyl-1picryl hydrazyl (DPPH) radical scavening activity of C. asiatica collected from domestic natural habitat (Hapcheon, Gyeongnam). In the growth characteristics of each resource, CA9 and CA10 were superior in characteristics of aerial part and in dry weight. In asiaticoside content analysis, CA5 and CA3 were high with 53.96 mg/g and 52.40 mg/g, respectively. CA12 showed the possibility of development because the resource showed high in total flavonoid (7.3 mg/g), total polyphenol (10.64 mg/g) and DPPH activity (11.96 mg AAE/g) among other resources. However, it is necessary to select a resource suitable for each characteristic of C. asiatica and to study charateristics through additional resources collection since the excellent growth characteristics of the collected resources do not necessarily coincide with the content and antioxidant activities.