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Vertical Distribution of Heavy Metal Concentrations in Sediment Cores and Sedimentation Rate Using $^{210}Pb$ Dating Technique in the Juam Reservoir (주암댐 호저 퇴적물에서의 수직적 중금속 분산과 $^{210}Pb$를 이용한 퇴적속도산정)

  • Lee Pyeong-Koo;Youm Seung-Jun;Yeon Gyu Hun;Chi Se-Jung;Kim Ji-Wook;Oh Chang-Whan;Kim Sun-Ok
    • Journal of Soil and Groundwater Environment
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    • v.10 no.1
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    • pp.43-57
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    • 2005
  • Twelve bottom sediments and three cores were collected in Juam reservoir for a study on transportation, which was controlled by particle grain size (2mm-200{\mu}m,\;200-100{\mu}m,\;100-50{\mu}m,\;50-20{\mu}m,\;<20{\mu}m), and vertical distribution of heavy metals. Sediment cores were sliced into 2 to 5 cm intervals to measure heavy metal concentrations in interstitial water and sediments with depth. Pb isotopic compositions of core samples were determined to calculate sedimentation rate. Regardless of sampling sites, levels of heavy metals and trace elements in bottom sediments are nearly constant with mean values of $14.9\;{\mu}g/g\;for\;As,\;0.81{\mu}g/g\;for\;Cd,\;30.7{\mu}g/g\;for\;Cu,\;34.7{\mu}g/g\;for\;Ni,\;63.3{\mu}g/g\;for\;Pb\;and\;87.9{\mu}g/g\;for\;Zn$. In general, Cu, Pb, Zn, Wi, and Cr in fraction of $<20{\mu}m$ exhibit the highest concentration, but content of As is the highest in grain size of $2\;mm-200\;{\mu}m$ and $200-100\;{\mu}m$. Fe and Mn occur as the dissolved compositions of the highest concentrations in interstitial waters and increase in their concentrations toward lower part of cores. On the contrary, concentrations of Zn and Cu show the highest value in the uppermost part in cores, suggesting these elements are released from reductive dissolution of hydroxides and oxidation of organic matters under different redox conditions. The highest accumulations of Cu, Ni, Pb, and Zn contents in the sediment cores are observed at 0-4 cm layers, and concentrations of Cu and Pb are especially high, implying these heavy metals are originated from anthropogenic sources. The apparent sedimentation rate estimated using unsupported $^{210}Pb$ is 0.91 cm $year^{-1}$, corresponding about 10 cm sedimentation in total depth since construction of Juam dam. These results will provide available information for management of bottom sediment in Juam reservoir.

Geological Structures and Geochemical Uranium Anormal Zone Around the Shinbo Mine, Korea (신보광산 주변지역의 지질구조와 우라늄 지화학 이상대)

  • Kang, Ji-Hoon;Lee, Deok-Seon
    • Economic and Environmental Geology
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    • v.45 no.1
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    • pp.31-40
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    • 2012
  • This paper examined the characteristics of ductile and brittle structural elements with detailed mapping by lithofacies classification to clarify the relationship between the geological structure and the geochemical high-grade uranium anormal zone and to provide the basic information on the flow of groundwater in the eastern area of Shinbo mine, Jinan-gun, Jeollabuk-do, Korea. It indicates that this area is mainly composed of Precambrian quartzite, metapelite, metapsammite, which show a zonal distribution of mainly ENE-WSW trend, and age unknown pegmatite and Cretaceous porphyry which intrude them. But the Cretaceous Jinan Group which unconformably covers them, contrary to assumption, could not be observed. The main ductile deformation structures of Precambrian metasedimentary rocks were formed at least through three phases of deformation [ENE striking regional foliation (D1) -> ENE or EW striking crenulation foliation (D2) -> WNW or EW trending open, tight, kink folds (D3)]. The predominant orientation of S1 regional foliation strikes ENE and dips south, being similar to the zonal distribution of Precambrian metasedimentary rocks. Most predominant orientation of high-angled brittle fracture (dip angle ${\geq}45^{\circ}$) [ENE (frequency: 24.3%) > NS (23.9%) > (N)NW (18.8%) > WNW (16.9%) > NE (16.1%) fracture sets in descending frequency order], which is closely related to the flow of groundwater, strikes ENE and dips south. It also agrees with the zonal distribution of metasedimentary rocks and the predominant orientation of S1 regional foliation. The next one strikes NS and dips east or west. Considering the controlling factor of the geochemical uranium anormal zone in the Shinbo mine and its eastern areas from the above structural data. the uranium source rock in these areas might be pegmatite and the geochemical uranium anormal zone in the Sinbo mine area could be formed by an secondary enrichment through the flow of pegmatite aquifer's groundwater into the Sinbo mine area like the previous research's result.

Variation and Distribution of Anions and Cations in the Aerosols of Gyorae Forests in Jeju Island (제주도 교래휴양림 지역의 대기질의 음이온 및 양이온의 분포와 변이성)

  • Sin, Bangsik;Im, Dongho;Lee, Keun Kwang
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.7
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    • pp.384-395
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    • 2018
  • This study was conducted to investigate the distribution and variation of the anion and cation number of aerosols in the A and B regions of Gyorae forests. Ions were measured using an ion number meter between 28 June and 13 July 2017. The total average number of anions and cations were $735ions/cm^3$ and $459.27ions/cm^3$, respectively, which were measured at five sites in A area at average temperature of $27.81^{\circ}C$, wind speed of 0.28 m/sec, and altitude of 455.7 m. The average number of anions and cations were $780ions/cm^3$ and $379.55ions/cm^3$, respectively, which were measured at all four sites in the B region at average temperature of $27.6^{\circ}C$, humidity of 80%, wind speed of 0.1 m/sec and altitude of 477 m. The number of anions and cations in the A and B regions was $757.5ions/cm^3$ and $419.41ions/cm^3$, respectively. The number of ions was highly variable for each measurement over time. The number of anions remained $275.73ions/cm^3$ higher than that of cations. The variance of the measured values of anions and cations between and within sites A and B was significant (p<.001) and there was a significant positive correlation between regional mean values of anions and cations. In conclusion, the temporal distribution and variation of the ion content in the Gyorae forests provide basic information regarding aerosol compositions and changes.

Spatial Distribution of Pigment Concentration Around the East Korean Warm Current Region Derived from Satellite Data - Satellite Observation in May 1980 - (위성원격탐사에 의한 동한난류 주변 해역의 색소농도 공간적 분포 -1980년 5월 관측을 중심으로 -)

  • Kim Sang Woo;Saitoh Sei-ich;Kim Dong Sun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.3
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    • pp.265-272
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    • 2002
  • Spatial distribution of Phytoplankton Pigment Concentration (PPC) and Sea Surface Temperature (SST) around the East Korean Warm Current (EKWC) was described, using both Coastal Zone Color Scanner (CZCS) images and Advanced Very High Resolution Radiometer (AVHRR) images in May, 1980. Water mass in this region can be classified into five categories in the horizontal profile of PPC and SST, nLw (normalized water-leaving radiance) images: (1) coastal cold water region associated with concentrations of dissolved organic material or yellow colored substances and suspended sediments, (2) cold water region of thermal frontal occurred by a combination of phytoplankton absorption and suspended materials, (3) warm water overlay region by the phytoplankton absorption than the suspended materials; (4) warm water region occurred by the low phytoplankton absorption, and (5) offshore region occurred by the high phytoplankton absorption. In particular, the highest PPC (>2.0 mg/m^3) area appeared in the CZCS and AVHRR images with a band shaped distribution of the thermal front and ocean color front region, which is located the coastal cold waters alonB western thermal front of the warm streamer of the EKWC. In this region, the highest PPC occurred by a combination of the high absorption of the phytoplankton (443 nm) and highest reflectance of suspended materials (550 nm). Another high PPC ($\simeq$$6\;mg/m^3$) appeared in the warm water overlay region inside warm streamer. High phytoplankton pigment concentration of this region was corresponding to the short wavelength of 443 nm, which represented phytoplankton absorption of the CZCS image.

Study of optimum growth condition of phase change Ge-Sb-Te thin films as an optical recording medium using in situ ellipsometry (In situ 타원법을 사용한 광기록매체용 Ge-Sb-Te 박막의 최적성장조건 연구)

  • Kim, Sang-Youl;Li, Xue-Zhe
    • Korean Journal of Optics and Photonics
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    • v.14 no.1
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    • pp.23-32
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    • 2003
  • The spectroe-ellipsometric constant $\Delta$, Ψ and the ellipsometric growth curves at the wavelength of 632.8 nm are collected. These are critically examined to find out the optimum growth condition of phase change $Ge_2Sb_2Te_5(GST)$ thin films as an optical recording medium. GST films are prepared using DC magnetron sputtering technique, under the selected experimental conditions of Ar gas pressure (5 mTorr, 7 mTorr and 10 mTorr), DC power of sputtering gun (15 W, 30 W and 45 W), and substrate temperature (from room temperature to 18$0^{\circ}C$). Based on the three film model, the density distribution of deposited GST films are obtained versus Ar gas pressure and DC power by analyzing spectro-ellipsometric data. The calculated evolution curves at the wavelength of 632.8 nm, are fit into the in situ observed ones to get information about the evolution of density distribution during film growth. The density distribution showed different evolution curves depending on deposition conditions. The GST films fabricated at DC power of 30 W or 45 W, and at Ar gas pressure of 7 mTorr turned out to be the most homogeneous one out of those prepared at room temperature, even though the maximum density difference between the dense region and the dilute region of the GST film was still significant (~50%). Finally, in order to find the optimum growth condition of homogeneous GST thin films, the substrate temperature is varied while Ar gas pressure is fixed at 7 mTorr and DC power at 30 W and 45 W respectively. A monotonic decrease of void fraction except for a slight increase at 18$0^{\circ}C$ is observed as the substrate temperature increases. Decrease of void fraction indicates an increase of film density and hence an improvement of film homogeneity. The optimum condition of the most homogeneous GST film growth turned out to be 7 mTorr of Ar gas pressure, 15$0^{\circ}C$ of substrate temperature. and 45 W of DC power. The microscopic images obtained using scanning electron microscope, of the samples prepared at the optimum growth condition, confirmed this conclusion. It is believed that the fabrication of homogeneous GST films will be quite beneficial to provide a reliable optical recording medium compatible with repeated write/erase cycles.

Research about a successful adopting for the CRM in the companies (기업에서의 성공적인 CRM 정착에 대한 연구)

  • Kim, Gipyoung
    • The Journal of Industrial Distribution & Business
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    • v.2 no.1
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    • pp.5-15
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    • 2011
  • Prior to the introduction of the CRM, we need to analyze the characteristics and the situations of the company, and should establish a clear vision of the CRM. And each company should identify elements and technologies for introducing the most suitable CRM for them, and optimize them, with long-term perspective. In addition, it requires the implementation strategy which integrates the existing company's routine marketing activities with the concept of the CRM. According to the implementation strategy, the company should improve the business process which is the most effective in investment step by step, and the information system strategy, which develops system investment gradually, should harmonize with it. First, we recognized that raising the company value is important by maximizing customer lifetime value (LTV) by understanding customer needs, and achieving the company's goal through customer satisfaction. Second, we understood that adopting the CRM should be accompanied by changes in the structure, business process and customer contact channels, and it can be successfully integrated with business when it gets proper understandings and attentions of the management. Third, the reality is that there are few cases of successful implementation of domestic companies, and some companies that successfully implement the system mean nothing but implement the solution for developing the CRM. Therefore, it needs to be observed for the long haul, and it seems that we need to approach more systematically to implementation cases for each industry about implementation of the CRM. Fourth, the CRM is no longer the preserve of major companies, and it is the time that medium and small sized enterprises also need it. Taking lesson from Switzerland's small size store merchants who successfully adopt right size of the CRM for their business, for domestic medium and small sized enterprises, the necessity to develop business through developing the CRM models which fit their situations and maintaining relationships with customers has been grown. Fifth, for adopting the CRM business processes, changing or converting the CRM system to the model which fits the company's situation is important rather than applying the advanced company's CRM system model. In other words, the CRM solution which can maximize their own strength by developing the CRM program that makes the most of features and characteristics of the company should be adopted.

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Distribution of Nutrients and Chlorophyll α in the Surface Water of the East Sea (동해 표층수 중 영양염과 Chlorophyll α의 분포 특성)

  • Yoon, Sang Chol;Yoon, Yi Yong
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.19 no.2
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    • pp.87-98
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    • 2016
  • During the period between July 3 and 27 of 2009, water samples were collected from the Russian coast at a depth of 30m from 26 stations (including Ulleung and Japan basins) onboard the Russian survey vessel R/V Lavrentyev following 4 lines (D, R, E, and A). The samples were analyzed for nutrients and chlorophyll a contents. All parameters exhibited higher values in warm waters than in cold waters ($NH_4:1.8-fold$, $PO_4:1.8-fold$, $SiO_2:1.2-fold$, and chlorophyll-${\alpha}$:1.9-fold), except nitrates, which was 1.4-fold higher in cold waters than in warm waters. The horizontal distribution of ammonia, phosphate, and chlorophyll-${\alpha}$ was very similar to each other and showed the highest values in the waters near Russia, where a upwelling influence of cold current and bottom water prevails, while relatively low distribution was observed at the Ulleung Basin. On the other hand, nitrates showed the highest concentration at the Ulleung Basin, which is under the direct influence of the Tsushima warm water, and showed a gradual decrease northward. The N/P ratio showed the highest value in the Tsushima middle water, rather than in the North Korean Cold Water, the Tsushima Warm Water was the primary source of nitrate flow into the East Sea. However, the average concentration of phosphate in the warm waters was < $0.2{\mu}M$, thereby limiting phytoplankton growth, while a high concentration of phosphate in cold waters showed a direct correlation with chlorophyll-${\alpha}$. The results of principal component analysis for the identification of primary factors that influence the marine environment showed that principal component I was water temperature and principal component II was influenced chlorophyll-${\alpha}$ and nutrients. Therefore, Study area has greatest influenced by water temperature, and clearly distinct cold and warm water regions were observed in the East Sea.

Distributions of Dissolved Pb and Cd in the Surface Water of East Sea, Korea (동해 표층수중 용존 Pb, Cd의 분포 특성)

  • Yoon, Sang Chol;Yoon, Yi Yong
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.18 no.2
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    • pp.64-73
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    • 2015
  • The distributions of Pb and Cd concentrations in the surface seawater of the East Sea were investigated during the R/V Lavrentyev cruise (July 2009) in which four transects from Russia shore to South were conducted to collect 26 surface water samples. The total dissolved concentrations of Pb and Cd were measured using ICP-MS (Perkin Elmer, DRC-e). In the coastal area, their concentrations of Russia shore (Pb, 0.08; Cd, 0.10 nM) were comparable for Cd but on the other hand, 6 times lower for Pb than Korea shore (Pb, 0.49; Cd, 0.11 nM). In the subregion, their concentrations of Warm region (Pb, 0.22; Cd, 0.01 nM) were about 1.7 times higher for Pb but 0.4 lower for Cd than Cold region (Pb, 0.13; Cd, 0.14 nM). The distributions of Pb and Cd concentrations were divided by lowest level at $10^{\circ}C$ of water temperature. Below $10^{\circ}C$, Pb and Cd concentrations increased when surface water temperatures decreased. Above $10^{\circ}C$, their concentrations increased with temperature, which showed highest concentrations in the Ulleung basin, directly influenced by flux from East Korean Warm Current and neighboring countrys (Korea and Japan). Specially, in the case of Pb, the concentrations decrease remarkablely with temperatures decrease from D10 directly influenced by flux from East Korean Warm Current, which shows highest Pb level. By comparing with other sea areas (Western Mediterranean, East Pacific), Pb concentrations in the East Sea were a little higher. The influence of East Korean Warm Current and neighboring countrys (Korea and Japan) may be relatively important. Therefore, the distribution of Cd may primarily be influenced by mixing of different water masses while the distribution of Pb may mainly be influenced by flux from East Korean Warm Current and atmospheric inputs. River inputs and interaction with particulate materials may also some roles for the distribution of these elements.

Plant Architecture and Dry Matter Production in Large-Grain Rice Variety (대립벼의 생산구조 특성과 물질생산)

  • 김정곤;전병태;김진기
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.40 no.5
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    • pp.655-661
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    • 1995
  • This study was conducted to get basic information of dry matter production and agronomic characteristics for increasing grain ripening in rice cultivar with large grains. Three cultivars which have different grain size were used. Of the two large grain cultivars, SR7796-3-1-5-1-l(SR7796F$_{7}$) had long culm and SR11269-13-3-4-2(SR11269F$_{6}$) had short culm. On the other hand, Tamjinbyeo was recommended cultivar had medium size of grain and culm. LAI was highest in Tamjinbyeo, followed by the SR11269F$_{6}$ and SR7796F$_{7}$, LAI decrement was higher in large grain cultivars than that of Tamjinbyeo after 20days after heading. Total dry weight(TDW) of areal part was highest in SR11269F$_{6}$, followed by the Tamjinbyeo and SR7796F$_{7}$. Dry weight (DW) of stem (leaf sheath+culm) at harvesting stage was decreased 15%, 12% in Tamjinbyeo, SR11269F$_{6}$, respectively, but was increased 5% in SR7796F$_{7}$ compared to heading stage. In distribution rate of each organ to TDW, distribution rate of leaf blade was low in large grain cultivar, but that of stem in Tamjinbyeo, SR7796F$_{7}$ and SR11269F$_{6}$ was 36%, 38% and 42%, respectively. In canopy architecture leaf blade weight was the highest 30~40cm, 40~50cm and 70~8Ocm above the ground in SR11269F$_{6}$, Tamjinbyeo and SR7796F$_{7}$, respectively. Range of panicle distribution in the canopy was 40cm in Tamjinbyeo, and was 70cm in large-grain cultivars. The results suggest that it has to take a growing interest in developing culture method for increasing LAI during growth stage, especially, around heading, in keeping green leaf till ripening stage and also in growing unformly plant within rice hill in large grain cultivars.cultivars.ltivars.

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Assessment of Particle Size Distribution and Pollution Impact of Heavy metalsin Road-deposited Sediments(RDS) from Shihwa Industrial Complex (시화산업단지 도로축적퇴적물의 입도분포 및 중금속 오염영향 평가)

  • Lee, Jihyun;Jeong, Hyeryeong;Ra, Kongtae;Choi, Jin Young
    • Journal of Environmental Impact Assessment
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    • v.29 no.1
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    • pp.8-25
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    • 2020
  • Industrialization has increased the production of road-deposited sediments (RDS) and the level of heavy metals in those RDS, which can have a significant impact on the surrounding aquatic environments through non-point pollution. Although the relationship between contamination characteristics and particle size of RDS is important for pollution control, there is very little information on this. In this study, we investigated the characteristics of grain size distribution and heavy metal concentrations in the road-deposited sediments (RDS) collected from 25 stations in Shihwa Industrial Complex. The environmental impact of RDS with particle size is also studied. Igeo, the contamination assessment index of each metal concentration, represents the RDS from Shihwa Industrial Complex are very highly polluted with Cu, Zn, Pb and Sb, and the levels of those metals were 633~3605, 130~1483, 120~1997, 5.5~50 mg/kg, respectively. The concentrations of heavy metals in RDS increased with the decrease in particle size. The particle size fraction below 250 ㎛ was very dominant with mass and contamination loads, 78.6 and 70.4%, respectively. Particles less than 125 ㎛ of RDS were highly contaminated and toxic to benthic organisms in rivers. RDS particles larger than 250 ㎛ and smaller than 250 ㎛ were contaminated by the surrounding industrial facility and vehicle activities, respectively. As a result of this study, the clean-up of fine particles of RDS, smaller than 125-250 ㎛, is very important for the control and reduction of non-point pollution to nearby water in Shihwa Industrial Complex.