• Title/Summary/Keyword: flow accumulation

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Effect of Cultivation Activity in Daecheong Lake Flood Control Site on Water Quality (대청호 홍수조절지 내 경작활동이 수질에 미치는 영향)

  • Choi, Hyeseon;Jeon, Minsu;Kim, Leehyung
    • Journal of Wetlands Research
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    • v.22 no.1
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    • pp.49-58
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    • 2020
  • The excessive use of fertilizer and compost in agricultural land increases the accumulation of nutrients in soil. The surplus nutrients in soil transported through surface and sub-surface flow can lead to water pollution problems and algal bloom. Moreover, nutrient accumulation and continuous crop cultivation changes the physical structure of the soil, which increases the potential of nutrient. The cultivation in the Daecheong Lake reservoir area may have a direct effect on the lake's water quality due to leaching and releasing of nutrients when water level rises. This research was carried out to analyze the physical and chemical properties of soil in the agricultural areas surrounding Daecheong Dam reservoir to provide basic data available for the establishment of Daecheong Lake water quality management measures. The soil of the Daecheong Lake reservoir was classified as sandy Loam, where surplus nutrients can be transported. Chemical compositions in the soil were found to be significantly affected by use of different fertilizer amounts. Nutrient outflow occurred during spring rainfall events from the rice paddy fields, whereas excess nutrients from summer to fall seasons originated from dry paddy fields. Nutrient outflow from dry paddy fields is mainly from sub-surface flow. Organic agricultural wastes from agricultural land and excessive vegetation inside the river was also evaluated to contribute to the increase in organic matter and nutrients of the river. The results can be used to select the priority management area designation and management techniques in the Daecheong Lake for water quality improvement.

Vertical Distribution of Bulk Density and Salts in a Plastic Film House Soil (깊이별 용적밀도가 다른 시설재배지 토양의 염류분포)

  • Kim, Pil-Joo;Lee, Do-Kyoung;Chung, Doug-Young
    • Korean Journal of Soil Science and Fertilizer
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    • v.30 no.3
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    • pp.226-233
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    • 1997
  • To investigate the salt accumulation in the plastic film house soils, bulk density, electrical conductivity(EC), exchangeable canons and water soluble anions were determined at different depths(0~60cm) in the salt-accumulated plastic film house soils in Yesan, Chungnam, Korea. Bulk density were increased from $1.2Mg/m^3$ to $1.5Mg/m^3$ as the depth changed from 0cm(top soil) to 30cm(subsoil) below the soil surface, whereas the bulk densities between 30cm to 60cm slightly decreased to $1.42Mg/m^3$. These changes of soil bulk densities might influence the porosity and pore size distribution, resulting in affecting the water flow throughout, soil layers. Electrical conductivity and Exchangeable sodium percentage(ESP) for 0 to 10cm soil layer were 5.08 dS/m and 6.4, respectively, while the EC was decreased to less than 1.63 dS/m in 20~30cm depth and about 0.7 dS/m. Salt accumulation patterns in the plastic film house soils might be influenced by the changes of the bulk densities in soil.

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Research on the Variation of Deposition & Accumulation on the Shorelines using Ortho Areial Photos (수치항공사진을 이용한 해안선 침퇴적변화에 관한 연구)

  • Choi, Chul-Uong;Lee, Chang-Hun;Oh, Che-Young;Son, Jung-Woo
    • Journal of Korean Society for Geospatial Information Science
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    • v.17 no.3
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    • pp.23-31
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    • 2009
  • The border of the shorelines in a nation is an important factor in determining the border of a national territory, but Korea's shorelines are rapidly changing due to the recent rise in sea level from global warming and growth-centered economic policy over the decades of years. This research was done centering on the areas having well-preserved shorelines as they naturally are and other areas having damaged shorelines in their vicinities due to artificial structures at the two beaches located at the neighboring areas and having mutually homogeneous ocean conditions with each other. First, this research derived the shorelines using the aerial photographies taken from 1947 until 2007 and revised the tidal levels sounding data obtained from a hydrographical survey automation system consisting of Echosounder[Echotrac 3100] and Differential Global Positioning System[Beacon]by using topographical data and ships on land obtained by applying post-processing Kinematic GPS measuring method. In addition, this research evaluated the changes and dimensional variations for the last 60 years by dividing these determined shorelines into 5 sections. As a result, the Haewundae Beach showed a total of 29% decrease rate in dimension as of the year 2007 in comparison with the year 1947 due to a rapid dimensional decline centering on its west areas, while the dimension of the Gwanganri Beach showed an increase in its dimension amounting to a total of 69% due to the decrease in flow velocity by artificial structures built on both ends of the beach-forming accumulation; thus, it was found that there existed a big difference in deposition & accumulation tendency depending on neighboring environment in spite of the homogeneous ocean conditions.

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Longitudinal Distribution of Zooplankton at 10.5°N in the Northeastern Pacific (북동태평양 북위 10.5°에서 동물플랑크톤의 경도별 분포 특성)

  • Kang, Jung-Hoon;Cho, Kyu-Hee;Son, Ju-Won;Kim, Woong-Seo
    • Ocean and Polar Research
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    • v.29 no.4
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    • pp.283-295
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    • 2007
  • We investigated the longitudinal variations in zooplankton abundances and their related physicochemical properties at nine stations located between $136^{\circ}W$ and $128^{\circ}W$ at $10.5^{\circ}N$ in the northeastern Pacific in summer 2004. Temperature, salinity, inorganic nutrients, chlorophyll-a (hereafter chl-a) and zooplankton ($>200\;{\mu}m$) were sampled within the depth from the surface to 200 m depth at $1^{\circ}$ longitude intervals. Zooplankton($>200\;{\mu}m$) samples were vertically collected at two depth intervals from surface to 200 m, consisting of surface mixed and lower layers (thermocline$\sim$200 m). Longitudinal distributional pattern of hydrological parameters (especially salinity) was physically influenced by the intensity of westward geostrophic current passage relating to the NEC (North Equatorial Current). Data from the longitudinal survey showed clear zonal distributions in the hydrological parameters(temperature, salinity and nutrients). However, spatial patterns of the chl-a concentrations and zooplankton abundances were mostly independent of the zonal distributions of hydrological parameters. The two peaks of zooplankton abundance in the surface mixed layer were characterized by different controlling factors such as bottom-up control from nutrients to zooplankton ($129^{\circ}W$) and accumulation by increment of friction force and taxonomic interrelationship ($133^{\circ}$ and $134^{\circ}W$). Divergence-related upwelling caused introduction of nutrients into surface waters leading to the increment of chl-a concentration and zooplankton abundances ($129^{\circ}W$). Increased friction force in relation to reduced flow rates of geostrophic currents caused accumulation of zooplankton drifting from eastern stations of study area($133^{\circ}$ and $134^{\circ}W$). Besides, high correlation between immature copepods and carnivorous groups such as chaetognaths and cyclopoids also possibly contributed to the enhanced total abundance of zooplankton in the surface mixed layer (p<0.05). Zooplankton community was divided into three groups (A, B, C) which consecutively included the eastern peak of zooplankton($129^{\circ}W$), the western peak($133^{\circ}$ and $134^{\circ}W$) and high nutrient but low chl-a concentration and zooplankton abundance ($136^{\circ}W$). Moreover, Group B corresponded to the westward movement of low saline waters(<33.6 psu) from 128 to $132^{\circ}W$. In summary, longitudinal distributions of zooplankton community was characterized by three different controlling factors: bottom-up control ($129^{\circ}W$), accumulation by increased friction force and relationships among zooplankton groups ($133^{\circ}$ and $134^{\circ}W$), and mismatch between hydrological parameters and zooplankton in the high nutrient low chlorophyll area ($136^{\circ}W$) during the study period.

Differential Hrd1 Expression and B-Cell Accumulation in Eosinophilic and Non-eosinophilic Chronic Rhinosinusitis With Nasal Polyps

  • Chen, Kun;Han, Miaomiao;Tang, Mengyao;Xie, Yadong;Lai, Yuting;Hu, Xianting;Zhang, Jia;Yang, Jun;Li, Huabin
    • Allergy, Asthma & Immunology Research
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    • v.10 no.6
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    • pp.698-715
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    • 2018
  • Purpose: Hrd1 has recently emerged as a critical regulator of B-cells in autoimmune diseases. However, its role in the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP) remains largely unexplored. This study aimed to examine Hrd1 expression and B-cell accumulation and their possible roles in CRSwNP. Methods: Quantitative real-time polymerase chain reaction, immunohistochemistry, enzyme-linked immunosorbent assay and Western blotting were used to assess gene and protein expression in nasal tissue extracts. Cells isolated from nasal tissues and peripheral blood mononuclear cells were characterized by flow cytometry. Local antibody production was measured in tissue extracts with a Bio-Plex assay. Additionally, changes in Hrd1 expression in response to specific inflammatory stimuli were measured in cultured dispersed polyp cells. Results: Nasal polyps (NPs) from patients with eosinophilic CRSwNP (ECRS) had increased levels of Hrd1, B-cells and plasma cells compared with NPs from patients with non-eosinophilic CRSwNP (non-ECRS) or other control subjects (P < 0.05). The average Hrd1 levels in B-cells in NPs from ECRS patients were significantly higher than those from non-ECRS patients and control subjects (P < 0.05). NPs also contained significantly increased levels of several antibody isotypes compared with normal controls (P < 0.05). Interestingly, Hrd1 expression in cultured polyp cells from ECRS patients, but not non-ECRS patients, was significantly increased by interleukin-$1{\beta}$, lipopolysaccharide and Poly(I:C) stimulation, and inhibited by dexamethasone treatment (P < 0.05). Conclusions: Differential Hrd1 expression and B-cell accumulation between the ECRS and non-ECRS subsets suggests that they can exhibit distinct pathogenic mechanisms and play important roles in NP.

Effect of sun ginseng potentiation on epirubicin and paclitaxel-induced apoptosis in human cervical cancer cells

  • Lin, Yingjia;Jiang, Dan;Li, Yang;Han, Xinye;Yu, Di;Park, Jeong Hill;Jin, Ying-Hua
    • Journal of Ginseng Research
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    • v.39 no.1
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    • pp.22-28
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    • 2015
  • Background: Sun ginseng (SG), a specific formulation of quality-controlled red ginseng, contains approximately equal amounts of three major ginsenosides (RK1, Rg3, and Rg5), which reportedly has antitumor-promoting activities in animal models. Methods: MTT assay was used to assess whether SG can potentiate the anticancer activity of epirubicin or paclitaxel in human cervical adenocarcinoma HeLa cells, human colon cancer SW111C cells, and SW480 cells; apoptosis status was analyzed by annexin V-FITC and PI and analyzed by flow cytometry; and apoptosis pathway was studied by analysis of caspase-3, -8, and -9 activation, mitochondrial accumulation of Bax and Bak, and cytochrome c release. Results: SG remarkably enhances cancer cell death induced by epirubicin or paclitaxel in human cervical adenocarcinoma HeLa cells, human colon cancer SW111C cells, and SW480 cells. Results of the mechanism study highlighted the cooperation between SG and epirubicin or paclitaxel in activating caspase-3 and -9 but not caspase-8. Moreover, SG significantly increased the mitochondrial accumulation of both Bax and Bak triggered by epirubicin or paclitaxel as well as the subsequent release of cytochrome c in the targeted cells. Conclusion: SG significantly potentiated the anticancer activities of epirubicin and paclitaxel in a synergistic manner. These effects were associated with the increased mitochondrial accumulation of both Bax and Bak that led to an enhanced cytochrome c release, caspase-9/-3 activation, and apoptosis. Treating cancer cells by combining epirubicin and paclitaxel with SG may prove to be a novel strategy for enhancing the efficacy of the two drug types.

Characteristics of Bed Profile Fluctuation According to Before & After Removal of the Sediment Protection Weir using HEC-6 model (HEC-6모형을 이용한 방사보 철거 전후에 따른 하상변동 특성)

  • Ahn, Seung-Seop;Lee, Soo-Sik;Choi, Yun-Young;Lee, Jeung-Seok
    • Journal of the Korean Society of Hazard Mitigation
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    • v.1 no.3 s.3
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    • pp.93-102
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    • 2001
  • In this study, the characteristics of river bed profile fluctuation are become possible to be used effectively in future estimation of Taehwa river general development plan through analysis and examination according to the effects of sediment protection weir located in the area of the estuary of Taehwa river's main channel using HEC-6 model. The flow conditions needed in analysis of the characteristics of river bed profile fluctuation refer the conditions of flow which secures 95 days in a year, flood flow, and design flood examined in the estimation of Taehwa river maintenance basic plan. First, in analysis result of river bed variation range, there is no significant variation in upstream section from Samho-gyo while there are the more active erosion and sedimentation as the more flow in downstream from Samho-gyo. Next, from the result of the capacity of sediment transfer, it is analyzed that sediment transfer capacity in the area of estuary of Taehwa river has no significant difference in before and after removal of the sediment protection weir when design flood flows while it is estimated that the more flow, the bigger sediment transfer capacity. Therefore, it is thought that the installation of a suitable hydraulic structure at the lowest point of Dong-chun tributary joins from the downstream of Taehwa river can be a good device to reduce the accumulation of sediments at the lowest point of Taehwa river considering the reduction plan of sediment inflow caused by removal of the sediment protection weir.

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A Study on the Selection of Environmental Impact Assessment Factors through Public Participation (주민참여를 통한 환경영향평가 항목선정에 관한 연구 : 원자력발전소 개발사업을 대상으로)

  • Kim, Kwi-Gon;Youn, So-Won;Sung, Hyun-Chan;Park, Byoung-Won
    • Journal of Environmental Impact Assessment
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    • v.4 no.1
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    • pp.25-35
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    • 1995
  • The objective of the study is to produce preferential impact assessment factors for Environmental Impact Assessment by considering regional features and public participation in the initial stages of EIA. In order to produce preferential impact assessment factors, the study was carried out through theoretical research and a survey of public awareness as a ways to reflect public participation based on theoretical research. The survey of public awareness was conducted in the form of an interview to review the impact which the construction of atomic power plants at Hyo-am village, Jang-an, Kyungsang Province and Bi-hak village, Suhsang-myon, Ulsan-Kun will have on the surrounding environment: to reflect public participation on deciding preferential assessment: and to determine the extent of alternatives of the proposed project. As the result of the study, the following were identified as preferential assessment factors in the settlement and surrounding areas cultivation marine products, change of temperature of seawater due to flow of warm water, land use(negative), noise vibration during construction, existing plants, erosion accumulation, influx of manpower for construction(negative), recreation landscaping during construction and operation, change in flow of transportation during construction, the quality of seawater during construction and operation were produced as preferential assessment factors in both settlement area and neighboring areas. In the settlement area, the educational environment(negative & positive) and positive aspects of the influx of manpower for construction were also identified as preferential assessment factors.

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A study on the relationship between the symptom of Shanghanlun(傷寒論) and the Nutritive-Gi(營氣) (『상한론(傷寒論)』 병증(病症)과 영기(營氣)의 관계에 대한 연구(硏究))

  • Bang, Jung-kyun
    • Journal of Korean Medical classics
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    • v.30 no.1
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    • pp.211-221
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    • 2017
  • Objectives : The practices of Wei-qi and Nutritive-qi are generally divided into external Mai and internal Mai. However, they are closely interrelated and practiced together. While taking these aspects into consideration, this paper attempts to make interpretations in relation with Nutritive-qi the disease pathogens that appear in Shanghanlun's disease symptoms. Methods : Using the practice and function of Nutritive-qi described in Huangdineijing, the paper shall make interpretations for the patterns of Mawhangtang, patterns of Gaejitang, and the pathologies of pain, oedema, and nosebleed as described in Shanghanlun. Results & Conclusions : The pain from the patterns of Gaejitang differ from that of the patterns of Mawhangtang. First, the pain from the the patterns of Gaejitang cannot be the main symptom. Even if there is a symptom of pain, it's severity is not serious. Second, the pain from the patterns of Gaejiang takes the form of stiffness, and not general bodily pain. The reason for this stiffness is because of the emptiness of Wei-qi that leads to the congestion of Nutritive-qi which in turn causes the lack of qi and blood flow in muscula area such as abdomins. The symptom of oedema where one's body becomes swollen comes from a number of pathogens. First, the flow of meridian becomes hindered due to external dampness, a character which tends to be adhesive when added with humidty, and this results in the blockage of water qi which then causes the coagulation of nutritive blood. Second, when toxic heat is repressed and blocked within the lesser-yang channel, lesser-yang meridian stops working, which causes nutritive blood to clog at the front and back of ears since lesser-yang channel flows through that portion of body. Third, although oedema is not specifically mentioned in the sentences, but there exists the patterns of Daechungyongtang where water lumps are formed due to the accumulation and blockage of watery dampness. The patterns of Daechungyongtang is cuased when meridian is hindered from externally discharging body fluid due to a problem with meridian that blocks the fumigated internal heat which turns into bodily fluid from being discharged externally.

A Study on the Characteristics of Physical and the Adsorption of Heavy Metals (갯벌의 물리적 특성과 중금속 흡착에 관한 연구)

  • Na, Young;Lee, Seong-Baeg
    • Journal of Korea Soil Environment Society
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    • v.5 no.3
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    • pp.25-33
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    • 2001
  • The study was performed to examine the influence of sea tide on a tideland composition by Saemankeum reclamation and to evaluate a correlation between the characteristics of physical and the pollution level of heavy metals. Also, it was investigated the characteristics of heavy metal adsorption through a batch experiment and applied to adsorption isotherm equations. In the results, the flow of sea tide occurred to accumulation action and had an effect on the content of heavy metals. It suggests that influence factors for the content of heavy metals in the tidal flat be grain size, cation exchange capacity and organic matter content. Adsorption capacity of heavy metals occurs to 90% adsorption rate for injection concentration within 30 minutes. The flow patterns in Saemankeum area will undergo a change for soil size distribution. In result, this soil size changed will effect the adsorption capacity of heavy metals.

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