• Title/Summary/Keyword: Site/soil characteristics

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Compositions and Characteristics of Atmospheric Aerosols Collected at the 1100 Site in Mt. Halla, Jeiu (제주도 한라산 1100 고지 대기 에어로졸의 조성 및 특성)

  • 김원형;강창희;신찬성;고선영;홍민선
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.2
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    • pp.145-156
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    • 2003
  • The atmospheric aerosols collected at the 1100 site located in Mt. Halla have been analyzed to investigate their compositions and chemical characteristics . The average concentrations of water-soluble cations were in the order of N $H_{4}$$^{+}$ > $Ca^{2+}$ > N $a^{+}$ > $K^{+}$ > $Mg^{2+}$ during the spring, showing high increase of $Ca^{2+}$ concentration with the value of 0.60 $\mu\textrm{g}$/ $m^3$, and N $H_{4}$$^{+}$> N $a^{+}$> $K^{+}$> $Ca^{2+}$ > $Mg^{2+}$ during the other seasons. The average concentrations of anions have shown in the order of S $O_{4}$$^{2-}$ > N $O_{3}$$^{[-10]}$ >C $l^{[-10]}$ for all seasons, and S $O_{4}$$^{2-}$ and N $O_{3}$$^{[-10]}$ had higher concentrations in spring with the values of 4.84 $\mu\textrm{g}$/ $m^3$ and 1.08 $\mu\textrm{g}$/ $m^3$, respectively. From the analytical data of size-segregated particles by cascade impactor sampling, the components of N $H_{4}$$^{+}$, S $O_{4}$$^{2-}$, N $O_{3}$$^{[-10]}$ and $K^{+}$ were distributed mainly in fine particles, but $Ca^{2+}$, N $a^{+}$, $Mg^{2+}$ and C $l^{[-10]}$ were included mostly in coarse particles. The correlation coefficients of nss-S $O_{4}$$^{2-}$/N $H_{4}$$^{+}$, nss-S $O_{4}$$^{2-}$/ $K^{+}$ and N $O_{3}$$^{[-10]}$ /nss-C $a^{2+}$ showed quite high values with 0.871, 0.857 and 0.654, respectively Based on the study of enrichment factors, it is considered that N $a^{+}$, $Mg^{2+}$, C $l^{[-10]}$ and $Ca^{2+}$ components were delivered from oceanic and soil sources, but S $O_{4}$$^{2-}$, N $O_{3}$$^{[-10]}$ and N $H_{4}$$^{+}$ might have other source origins. The factor analysis study showed the aerosol at the 1100 site was influenced mainly by anthropogenic factors, followed by oceanic and soil factors. followed by oceanic and soil factors.

Case Study of Dynamic Amplification Characteristics of the Seismic Stations Using Observed Seismic Waves (관측지진파를 이용한 지반증폭특성 사례분석)

  • Lee, Jundae;Kim, Junkyoung
    • Journal of the Korean GEO-environmental Society
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    • v.10 no.1
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    • pp.35-41
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    • 2009
  • It is necessary to consider the site amplification for estimating SSI (soil structure interaction) and seismic source with more confidence. The horizontal to vertical (H/V) ratio technique in spectral domain is one of several techniques to estimate empirical site transfer function. The technique, originally proposed by Nakamura (1989), is applied to analyze the surface waves in the microtremor records. However, the application of this technique has been widened to the shear wave energy of strong motions for estimating site amplification. The purpose of this paper is to estimate spectral ratio using observed data at the seismic stations distributed within Southern Korean Peninsula from the Fukuoka earthquake including 11 aftershocks. The results show that each station has the its own characteristics of the specific resonance, high-band, and low-band frequency. The characteristics of the resonance frequency is more important because the quality of the seismic records are dependent on the resonance frequency. The result can be used for the study of site classification and removal of the site amplification effects from observed records can give us more reliable seismic source parameters.

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Characteristics of the Strength Change of Dredged Soil by Tide Influence (조석 영향에 의한 해성준설토의 강도변화 특성에 관한 연구)

  • Chun, Byung-Sik;Kim, Bong-Su;Lee, Won-Taek;Do, Jong-Nam
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.03a
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    • pp.1071-1074
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    • 2008
  • In this study, the behavior of dredged soil was measured by repeated tide and analyzed the change of settlements and cone penetration resistance by centrifuge model about dredged soil of Kunsan-Janghang site that maximum tidal range is 7.4m. Consequently the settlements of dredged soil by repeated tide in the 2nd month was 0.489 m. After 12th month, the total settlements was 0.524 m in the model. It meaned the settlements of dredged soil by repeated tide in the 2th month was 80% of the settlements. Also, with the lapse of time, cone penetration resistance increased centrifuge model test for catching the strength change of dredged soil by repeated tide. After 10th month, there were not almost changes. cone penetration resistance in 10th month was measured more 3.5~5.6 times than that in its early stages. Also, with the lapse of time, cone penetration resistance increased almost linearly. And, when we surveyed the relation between cone penetration resistance and time, as depth increased, cone penetration resistance rose.

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A Estimation of Soil Conversion Factor Using Digital Photogrammetry and 3D Laser Scanner (디지털사진측량 및 3D 레이저스캐너를 이용한 토랑환산계수의 산정)

  • Lee Jae-Kee;Jung Sung-Heuk;Lee Kye-Dong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.24 no.2
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    • pp.227-234
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    • 2006
  • Ministry of construction & transportation is operating for the soil and rock information system and is considered to accurate application of soil conversion factor that is essentially necessary for accurate calculation of earth volume. Since the balance of cutting earth in public work, the plan of spoil bank or borrow pit are directly related to construction costs, accurate calculation of earth volume and efficient scheme of haul are important. As such, this study has provided methods that can acquire information that is more rapid, applicable to job sites, and trustworthy by comparing resultant values of photogrammetry, laser scanning, or inside job site experimentations, and calculated soil conversion factor by applying photogrammetry and laser scanning methods for hard rock that has difficulty in calculating soil conversion factor. The study can provide alternatives that can resolve the problems of unbalanced earth volume that may arise in applying to plans the earth conversion factor that relies on planning books and experience without considering the characteristics of job site earth, and can establish its relevancy by calculating soil conversion factor for hard rock that has relative difficulties in doing inside or job site testing.

The Ecological Management on Consideration of Vegetation Structure at Goduck Riverside Restoration Area in Hangang, Seoul (서울시 한강변 고덕 수변 생태복원지의 식물생태특성을 고려한 생태적 관리방안)

  • 이경재;한봉호;김정호;배정희
    • Journal of the Korean Institute of Landscape Architecture
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    • v.32 no.2
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    • pp.86-101
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    • 2004
  • This study was conducted to present the ecological management of Goduk Riverside Restoration Area in Hangang, Seoul by analyzing the change of the vegetation structure. The survey site was classified into three groups. These were the vegetation restoration area, the dry plant area, and the swampy plant area. There were 141 taxa including naturalized plants and 13 species recorded in 2001 and 258 taxa including naturalized plants and 42 species were recorded in 2003 by monitoring. Monitoring results showed that the alien plants such as Humulus japonicus expanded continuously except in the vegetation restoration area. It was found that the growing status of planted shrub plants were poor, and the naturalized plants status was thriving, and the soil environment was bad in the vegetation restoration area. The alien plants such as Humulus japonicus and Aster pilosus dominated continuously in the dry plant area. The swampy native herb plants number was decreased, but the Humulus japonicus community was expanded caused by the soil drying in the swampy plant area. Soil analysis showed that the soil acidity, the available phosphates and the concentration of calcium were highly effected by cultivation. We propose ecological management as follows based on the results of the change of vegetation and soil characteristics. The vegetation restoration area should be managed by visitor's characteristics. Replanting vegetations should be based on soil characteristics. The removal of naturalized plants and established monitoring with plots is also needed. In the dry plant area and the swampy plant area, naturalized plants need to be removed in order to facilitate bio-diversity and monitoring.

Studies on the Tree Growth and Soil Environmental Characteristics in the Planting Zone on the Back Slope of Dam (댐체 비탈면 녹화지역의 수목 생장 및 토양환경 특성에 관한 연구)

  • Bahn, Gwon-Soo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.24 no.3
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    • pp.85-98
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    • 2021
  • In this study, the characteristics of tree growth and soil environment were analyzed at 5 sites that had been planted on the back slope of dam for more than 15 years in Korea. First, as a result of investigating the growth of 15 trees planted on the back slope of the dam, the average height was 10.6m, diameter at roots was 27.3cm, and DBH was 22.9cm, showing good growth status of most of the trees. In particular, the growth levels of pine, hackberry, and oak were similar or better than those of general forests and artificial ground. As a result of excavating and investigating the roots of trees, horizontal roots grew well in the left and right directions of the back slope of the dam, and the growth of vertical roots was insufficient. Currently, the roots of trees do not directly affect dam safety, but they may continue to grow in the long term and interfere with dam management. Second, the physicochemical characteristics of the soil on the back slope of dam were generally above the intermediate level in terms of landscape design standards, and were similar to those of the domestic forest soil. Therefore, although it was judged to be suitable for plant growth, isolation of the site, soil acidification, and nutrient imbalance may affect tree growth and forest health in the long term. Through this study, it was possible to confirm the potential and applicability of planting area on the back slope of dam as an ecological base. Continuous monitoring is required for safety management and ecological value of dams in the future, and through this, it will be possible to secure the feasibility of planting trees on the slopes of new or existing dams and improving management.

Change of Vegetation Characteristics and Soil Chemical Properties at Saemangeum Reclaimed Land in Korea (새만금 신간척지 식생과 토양화학성의 변화)

  • Kim, Sun;Jeong, Jae-Hyeok;Lee, Jang-Hee;Choi, Weon-Young;Lee, Kyeong-Bo;Im, Il-Bin
    • Weed & Turfgrass Science
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    • v.2 no.3
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    • pp.260-266
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    • 2013
  • This study was conducted to investigate changes of vegetation and soil characteristics to tidal land of Saemangeum reclaimed land from 2010 to 2012. Soil salinity was 0.16-22.3 dS $m^{-1}$ in the first survey, while the three years later, it was decreased to 0.12-4.22 dS $m^{-1}$. Vegetations were classified as 6 families and 26 species but it was increased to 8 families and 31 species after three years. Numbers of average species in survey site were increased from 7.1 species to 10.6 species. Numbers of vegetation were increased at each survey sites except for survey site 7 : there was decreased halophyte according to decrease in the soil salinity. Biomass production was increased at low production site, and showed highest production in area of dominant vegetation as Phragmites communis. Simpson's dominance ratio(SDR) of main vegetation as Phragmites communis, Calamagrostis epigeios were increased but Suaeda maritima, Salicornia europaea, Puccinellia nipponica and Zoysia sinica were decreased.

A Study of Characteristics of Seeding Plants through Improvements of Dredge Vegetation-Base -Focus on Site 14 in Nakdong-gang- (준설토 파종식물의 생육경향 및 관리방안 연구 -낙동강 14공구 중심으로-)

  • Kim, Nam Choon;Ann, Phil Gyun;Nam, Sang Jun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.15 no.1
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    • pp.141-154
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    • 2012
  • This study was launched to verify the effective composition of plant species and its management program most suited for the dredged soiled area near Nakdong River Site 14. The improvement methods of planting base and the composition of plants such as silver grass, reed, and some colonies in aesthetic effect were studied. To search the management methods to decrease the confining pressure risen from the burried seeds which would consequently harm the previously seeded plants, experimental construction process was measured on the site. The purpose of this experiment was to figure out which part of the improvement on the plant base has the most significant effect for the revegetation of infertile, dredged soil, to verify the easily seeded, developing plants among seeded plants, and finally, to find the restoration model using plants near the dredged soil around riverside. 8 seeded plants and 23 invaded species were appeared which among the emerged plants, development of Aster yomena MAKINO, Lotus corniculatus var. japonica Regel, Trifolium repens L, and Dianthus longicalyx Miq were proved to be brought up well. Difference risen from the seed composition were not noticeable until 150day since the germination was proceeded mainly by Aster yomena MAKINO. The experimental plot with dredging sand+organic fertilizer method of construction and dredging sand+soil conditioner method showed most development while the effect of the plot with only the soil base of dredging sand stayed low. Another important method for the management of infertile, dredged soil base would be the removal of disturbing species which the experiment showed the tied relationship between the removal of disturbing species and development of seeding plants. Although this study was carried out focused on the Nakdong River Project, the study suggests the general management program that the removal of disturbing species such as Humulus japonicus Sieboid & Zucc. and Pueraria lobata (Willd.) Ohwi in times around rainy season(60days after seedling) would be effective for the easy growth of revegetation plants.

A Study on the Landscape Design Strategies for Regeneration of Post-Industrial Sites of the Beijing-Tianjin-Tangshan Region in China (중국 경진당(京津唐) 지역 산업 이전적지(移轉跡地) 재생 전략 연구)

  • Zhang, Xin-Yu;Choi, Jung-Mean
    • Journal of the Korean Institute of Landscape Architecture
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    • v.50 no.4
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    • pp.1-19
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    • 2022
  • This study aims to discover the implications through the analysis of the characteristics and design strategies of the regeneration of the post-industrial sites in the metropolitan the Beijing-Tianjin-Tangshan region. This study provides a basis for future research and theoretical strengths for post-industrial site regeneration practices. The results of the study are as follows. First, post-industrial site regeneration projects pursue diverse goals such as industrial heritage preservation, cultural creativity, and neighborhood revitalization in the Beijing-Tianjin-Tangshan region. Second, in the design process, the characteristics and spatial levels of the space are enhanced by utilizing the original industrial space, incorporating transitional space, and using industrial facilities of varying heights. Third, old and new landscape elements are harmoniously integrated through the rational use of industrial relics and the appropriate addition of new elements. Fourth, the design emphasizes ecological soil restoration and the use of native and adaptable plants that have the capacity to remediate polluted soil. Fifth, the design combines modern artistic elements, such as sculpture and graffiti art to enrich the site and promote the revival of the post-industrial site. Sixth, urban events and public activities are actively programmed to vitalize the regenerated site.

Crack Form and Soil Physical Properties in Land Creeping area on Okjong, Hadong (하동군 옥종면 땅밀림 산사태지의 인장균열 형태와 토양 물리성 변화)

  • Kim, Ki-Dae;Park, Jen-Hyeon;Lee, Chang-Woo;Kang, Min-Jeng
    • Journal of Korean Society of Forest Science
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    • v.105 no.4
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    • pp.435-440
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    • 2016
  • This study was carried out to examine of soil physical property and crack shape by collapse process on landslide area (by land creeping) in Hadong, Gyeongnam. We investigated morphological characteristics (length, depth, cut slope) between main crack and local crack, soil physical properties change between undisturbed section and disturbed section. As a result, morphological characteristics of crack showed no significant difference main crack between local crack. In case of soil physical property variation, soil liquid phase was significantly higher at 31-40 cm of soil depth in disturbed section. And this result is likely to be due to site factors.