• Title/Summary/Keyword: loess

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Hydrogeology and Water Chemistry of the Friar Tuck Abandoned Coal Mine Site, Indiana, USA (미국 인디아나주 Friar Tuck 폐탄광의 수리지질 및 수질)

  • Park, Jung-Chan
    • Journal of the Korean Society of Groundwater Environment
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    • v.3 no.2
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    • pp.70-79
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    • 1996
  • The Friar Tuck Abandoned Coal Mine site is one of the most complexly disturbed areas in the midwestern United States. The deposits of gob and tailings contain high concentrations of pyrite, whose oxidation contributes to the acidification of soil and water and prevents the growth of vegetation. In an effort to quantitatively evaluate the effects of reclamation techniques, detailed monitoring program was performed. Water samples were collected from surface water, groundwater, and pore water from the unsaturated zone during a period of five years. According to the results, The spoil deposits are a relatively minor source of contamination and gob piles are the source of severe contamination to surface water and groundwater. But, loess and till beneath the gob piles effectively prevent the contaminated water migration from the source. Surface layers of the gob piles and the tailing deposits are less toxic than the interior of the deposits as a consequence of weathering over several decades. Acid mine drainage is in a post-peak stage and acid formation potential is probably situated in the unsaturated zone of refuse.

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The Features Associated with the Yellow Sand Phenomenon Observed in Korea in Wintertime (겨울철 황상 현상의 특징)

  • 전영신;김지영;부경온;김남욱
    • Journal of Korean Society for Atmospheric Environment
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    • v.16 no.5
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    • pp.487-497
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    • 2000
  • Spring time is a favorable season to be easily observed the Yellow Sand phenomenon in East Asia. In particular most of the phenomenon tend to occur in April. However, Yellow Sand phenomenon was observed from almost the whole country of Korea in winter of 1966, 1977 and 1999. The features of the synoptic weather pattern in the source regions, air stream flow between the source region and Korea, the measurement of TSP concentration, aerosol size distribution, and chemical composition of snow samples associated with Yellow Sand phenomenon were investigated. The result showed the characteristic evolutionary feature of the synoptic system associated with Yellow Sand phenomena, that is, a strong low level wind mobilized the dust within 2 or 3 days before Yellow Sand phenomenon being observed in Seoul. The wind was remarkably intensified in the source region on January 24, 1999 under the strong pressure gradient, A trajectory analysis showed that the Yellow Sand particle could be reached to Korea within 2 days from the source region, Gobi desert, through Loess plateau and Loess deposition region. The TSP concentration at the top of Kwanak mountain during the Yellow Sand phenomenon is abruptly increasing than the monthly mean concentration. The size resolved number concentration of aerosols ranging from 0.3 to 25${\mu}{\textrm}{m}$ was analyzed during Yellow Sand episode. It was evident that aerosols were distinguished by particles in the range of 2-3 ${\mu}{\textrm}{m}$ to result in the abrupt increase in January 1999, After Yellow Sand phenomenon, there was heavy snow in Seoul. By the analysis of snow collected during that time, it was observed that both the Ca(sup)2+ concentration and pH were increased abnormally compared to those in the other winter season.

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Determining the Required Vitamin D Level for Bone Health Based on Bone Turnover Markers

  • Ismail, Tuan Salwani Tuan;Muda, Bayani Che;Rosdi, Roznie Aida Mohd;Zainuddin, Azalina;Isa, Salbiah;Mustapaha, Zulkarnain
    • Korean Journal of Clinical Laboratory Science
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    • v.49 no.4
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    • pp.337-344
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    • 2017
  • To date, no clear threshold that has been established for defining an adequate store of vitamin D for bone health. Therefore, this study aims to determine the required level of vitamin D to maintain a healthy skeleton based on bone remodelling process among healthy adult population. This was a cross sectional study, involving a healthy adult population in Kota Bharu, Malaysia, aged 18~50 years. We measured serum 25(OH)D (vitamin D), serum parathyroid hormone (PTH), serum C-terminal telopeptide of type 1 collagen (CTX), and Procollagen 1 Intact N-Terminal (P1NP) in 120 healthy adults selected via multi stage sampling (64 males, 56 females) from 6 subdistricts in Kota Bharu. The mean level of 25(OH)D was 23.50 (${\pm}8.74$) nmol/L. There was a significant difference of the vitamin D level between genders ($26.81{\pm}8.3nmol/L$ vs $19.72{\pm}7.68nmol/L$ in males and females respectively) (p value<0.001). More than 50% of female subjects had 25(OH)D less than 20 nmol/L, while only 20.3% of male subjects had 25(OH)D below 20 nmol/L. Based on the LOESS plot, the bone turnover markers showed a plateauing result, at the 25(OH)D level of 35 nmol/L for CTX and 20 nmol/L for P1NP. Contrastingly, PTH showed a step rise in the 25(OH)D level of 20 nmol/L. Based on the LOESS plot for CTX, P1NP and PTH versus 25(OH)D, level of vitamin D between 20 to 35 nmol/L is recommended to maintain healthy skeleton.

Number of sampling leaves for reflectance measurement of Chinese cabbage and kale

  • Chung, Sun-Ok;Ngo, Viet-Duc;Kabir, Md. Shaha Nur;Hong, Soon-Jung;Park, Sang-Un;Kim, Sun-Ju;Park, Jong-Tae
    • Korean Journal of Agricultural Science
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    • v.41 no.3
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    • pp.169-175
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    • 2014
  • Objective of this study was to investigate effects of pre-processing method and number of sampling leaves on stability of the reflectance measurement for Chinese cabbage and kale leaves. Chinese cabbage and kale were transplanted and cultivated in a plant factory. Leaf samples of the kale and cabbage were collected at 4 weeks after transplanting of the seedlings. Spectra data were collected with an UV/VIS/NIR spectrometer in the wavelength region from 190 to 1130 nm. All leaves (mature and young leaves) were measured on 9 and 12 points in the blade part in the upper area for kale and cabbage leaves, respectively. To reduce the spectral noise, the raw spectral data were preprocessed by different methods: i) moving average, ii) Savitzky-Golay filter, iii) local regression using weighted linear least squares and a $1^{st}$ degree polynomial model (lowess), iv) local regression using weighted linear least squares and a $2^{nd}$ degree polynomial model (loess), v) a robust version of 'lowess', vi) a robust version of 'loess', with 7, 11, 15 smoothing points. Effects of number of sampling leaves were investigated by reflectance difference (RD) and cross-correlation (CC) methods. Results indicated that the contribution of the spectral data collected at 4 sampling leaves were good for both of the crops for reflectance measurement that does not change stability of measurement much. Furthermore, moving average method with 11 smoothing points was believed to provide reliable pre-processed data for further analysis.

An Experimental Study on Quality Properties of Living Concrete Using Loess-Magnesia Composites (황토-마그네시아 복합체 활용 Living Concrete의 품질특성에 관한 실험적 연구)

  • Yun-Wang, Choi;Young-Woo, Na;Yong-Woo, Kwon
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.10 no.4
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    • pp.498-505
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    • 2022
  • In this study, as a result of eva lua ting the quality properties of Living Concrete, the flow of the table showed a tendency to decrease as the mixing ratio of ocher increased. Compressive strength was found to decrease with increasing loess mixing ratio. Density properties were evaluated for weight reduction, As a result of comparison with the panel using cement as a comparison group, the density was measured to be a bout 20 % lower than that of the cement panel, and it is judged that it is less affected by the load and can be installed in the structure. As a result of evaluating the panel temperature reduction, there was a difference in the temperature reduction with time. It is judged that the panel planted with moss has a lower temperature than the panel without moss, so it is judged that it can be used in a vertical greening system.

Removal efficiency of various coagulants for Microcystis, Anabaena and Oscillatoria at different cell densities

  • Han, Joo Eun;Park, Soo Hyung;Yaqub, Muhammad;Yun, Sang Leen;Kim, Seog-ku;Lee, Wontae
    • Membrane and Water Treatment
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    • v.13 no.1
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    • pp.15-20
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    • 2022
  • The continuous industrial growth increases the volume of pollutants discharged into the water, which induces Cyanobacteria in the receiving bodies. The removal of various cyanobacteria such as Microcystis, Anabaena, and Oscillatoria was explored to analyze their removal characteristics using different chemical and mineral coagulants. The chemical coagulants, including poly aluminium chloride (PACl), Alum, and mineral coagulants such as Loess and Illite, were tested to remove selected cyanobacteria. Results indicated that the removal rate increased with coagulant dosage regardless of the type of coagulant. The removal of selected cyanobacteria using chemical coagulant was found in the order: Microcystis > Anabaena > Oscillatoria. The PACl coagulant showed the most efficient removal rate for Microcystis, Anabaena, Oscillatoria. Removal rate of Microcystis conducted by PACl showed 92% at 100,000 cells/mL and 98.4% at 1,000,000 cells/mL whereas Illite showed lower 70% and Loess showed lower 50% in both 100,000 cells/mL and 1,000,000 cells/mL. The removal rate of Anabaena and Oscillatoria by PACl and Alum was higher 80%, while the other coagulants exhibited lower than 75% at 1,000,000 cells/mL. The removal rate of Oscillatoria by PACl was 80.1%, while the other coagulants exhibited lower than 70% at 1,000,000 cells/mL. Moreover, the mineral coagulants showed better removal efficiency at a higher concentration than low concentration during experiments. Therefore, removing cyanobacteria from water streams can be improved through coagulation by selecting a specific coagulant for a particular type of algae.

Characterization of Cement Solidification for Enhancement of Cesium Leaching Resistance (세슘 침출 저항성 증진 시멘트 고화체의 제조 및 특성 평가)

  • Kim, Gi Yong;Jang, Won-Hyuk;Jang, Sung-Chan;Im, Junhyuck;Hong, Dae Seok;Seo, Chel Gyo;Shon, Jong Sik
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.16 no.2
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    • pp.183-193
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    • 2018
  • Currently, the Korea Atomic Energy Research Institute (KAERI) is planning to build the Ki-Jang Research Reactor (KJRR) in Ki-Jang, Busan. It is important to safely dispose of low-level radioactive waste from the operation of the reactor. The most efficient way to treat radioactive waste is cement solidification. For a radioactive waste disposal facility, cement solidification is performed based on specific waste acceptance criteria such as compressive strength, free-standing water, immersion and leaching tests. Above all, the leaching test is important to final disposal. The leakage of radioactive waste such as $^{137}Cs$ causes not only regional problems but also serious global ones. The cement solidification method is simple, and cheaper than other solidification methods, but has a lower leaching resistance. Thus, this study was focused on the development of cement solidification for an enhancement of cesium leaching resistance. We used Zeolite and Loess to improve the cesium leaching resistance of KJRR cement solidification containing simulated KJRR liquid waste. Based on an SEM-EDS spectrum analysis, we confirmed that Zeolite and Loess successfully isolated KJRR cement solidification. A leaching test was carried out according to the ANS 16.1 test method. The ANS 16.1 test is performed to analyze cesium ion concentration in leachate of KJRR cement for 90 days. Thus, a leaching test was carried out using simulated KJRR liquid waste containing $3000mg{\cdot}L^{-1}$ of cesium for 90 days. KJRR cement solidification with Zeolite and Loess led to cesium leaching resistance values that were 27.90% and 21.08% higher than the control values. In addition, in several tests such as free-standing water, compressive strength, immersion, and leaching tests, all KJRR cement solidification met the waste acceptance or satisfied the waste acceptance criteria for final disposal.

Effect of Sludge Characteristics on the Sedimentation of Bulking Sludge (팽화 슬러지의 침전에 미치는 슬러지 성상의 영향)

  • Kim, Dong-Seog;Park, Young-Seek
    • Journal of Environmental Science International
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    • v.15 no.12
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    • pp.1177-1183
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    • 2006
  • This study was carried out to evaluate effect of sludge characteristics (pH, SVI, anaerobic storage, wet density and growth phase) on the sedimentation of bulking sludge of paper manufacturing plant. The results showed that mix hulking sludge with sewage sludge (10-60%) caused the decrease of SVI, the settled sludge concentration was increased. Increase of anaerobic storage time (0 to 8 day) was increased SVI, sedimentation performance was deteriorated. The sedimentation was improved by addition of loess (0.2-5.0 g/L), because wet density of sludge was increased and SVI was decreased. At an exponential phase, the ratio of sedimented/growthed sludge concentration was decreased, the ratio was increased after stationary phase.

Three Dimensional CERES Plot in Generalized Linear Models (일반화선형모형에서의 3차원 CERES그림)

  • Kahng, Myung-Wook;Kim, Bu-Yong;Jeon, Jin-Young
    • The Korean Journal of Applied Statistics
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    • v.21 no.1
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    • pp.169-176
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    • 2008
  • We explore the structure and usefulness of three dimensional CERES plot as a basic tool for dealing with curvature as a function of the new predictors in generalized linear models. If predictors have nonlinear effects and there are nonlinear relationships among the predictors, the partial residual plot is not able to display the correct functional form of the predictors. Unlike this plots, the CERES plot can show the correct form. This is illustrated by simulated data.

Development of Golf-wear Design depicted on Natural Image used by Natural Dyeing (천연염색을 이용한 자연적 이미지의 골프웨어 디자인 개발)

  • Jang, Ae-Ran
    • Korean Journal of Human Ecology
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    • v.17 no.3
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    • pp.501-509
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    • 2008
  • This research intends to help local small fashion industry to outgrow its limitation, preserving and developing environment-friendly dyeing tradition in Jeju renowned for persimmon juice dyeing. The study, then, aims to develop eco-friendly golf-wear designs, with maximizing advantages of natural dyeing (with persimmon juice, indigo plant, gallnut, cochineal, turmeric, and loess) such as rot-proofness, bacteria-proofness, stench-proofness and block of ultraviolet rays. The results are as follows: first, natural fabrics such as muslin(cotton 100%), linen(linen 100%) and spandex(mixed cotton 98%, polyurethane 2%) were developed into eco-friendly ones colored with various natural dye sources. Second, four kinds of golf-wear design were developed to stand out golf wear's natural image, focused on classic, neo-minimal style. The characteristic details and design elements of sportswear were added to basic golf wear design. Therefore, it is hopeful that those designs of naturally dyed golf wear for women could be utilized for other various purposes in the future.