• Analytical Science and Technology
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• v.31 no.6
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• pp.240-246
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• 2018

The present study analyzed standard samples of three types of aluminum matrix certified reference materials (CRM) using GD-MS. Calibration curves were constructed for 13 elements (Mg, Si, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Sn, and Pb), with the slope representing the relative sensitivity factor (RSF). The x- and y-axes of the calibration curve represented ion beam ratio (IBR) and the authenticated value of the standard sample, respectively. In order to evaluate precision and linearity of the calibration curve, RSD and the coefficient of determination were calculated. Curve RSD for every element reflected high precision (within 10 %). For most elements, the coefficient of determination was ${\geq}0.99$, indicating excellent linearity. However, vanadium, nickel, and gallium curves exhibited relatively low linearity (0.90~0.95), likely due to their narrow concentration ranges. Standard RSF was calculated using the slope of the curve generated for three types of CRM. Despite vanadium, nickel, and gallium exhibiting low coefficients of determination, their standard RSF resembled that of the three types of CRM. Therefore, the RSF method may be used for element quantitation. Standard iron matrix samples were analyzed to verify the applicability of the aluminum matrix standard RSF, as well as to calculate the RSD-estimated error of the measured value relative to the actual standard value. Six elements (Al, Si, V, Cr, Mn, and Ni) exhibited an RSD of approximately 30 %, while the RSD of Cu was 77 %. In general, Cu isotopes are subject to interference: $^{63}Cu$ to $^{54}Fe^{2+}-^{36}Ar$ and $^{65}Cu$ to $^{56}Fe-Al^{3+}$ interference. Thus, the influence of these impurities may have contributed to the high RSD value observed for Cu. To reliably identify copper, the resolution should be set at ${\geq}8000$. However, high resolutions are inappropriate for analyzing trace elements, as it lowers ion permeability. In conclusion, quantitation of even relatively low amounts of six elements (Al, Si, V, Cr, Mn, and Ni) is possible using this method.

• The Korean Journal of Nuclear Medicine
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• v.32 no.4
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• pp.332-343
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• 1998

Purpose: The purpose of this study was to assess the diagnostic accuracy of various quantitation methods using F-18-fluorodeoxyglucose (FDG) in patients with malignant or benign lung lesion. Materials and Methods: 22 patients (13 malignant including 5 bronchoalverolar cell cancer; 9 benign lesions including 1 hamartoma and 8 active inflammation) were studied after overnight fasting. We performed dynamic PET imaging for 56 min after injection of 370 MBq (10 mCi) of FDG. Standardized uptake values normalized to patient's body weight and plasma glucose concentration (SUVglu) were calculated. The uptake rate constant of FDG and glucose metabolic rate were quantified using Patlak graphical analysis (Kpat and MRpat), three compartment-five parameter model (K5p, MR5p), and six parameter model taking into account heterogeneity of tumor tissue (K6p, MR6p). Areas under receiver operating characteristic curves (ROC) were calculated for each method. Results: There was no significant difference of rate constant or glucose metabolic rate measured by various quantitation methods between malignant and benign lesions. The area under ROC curve were 0.73 for SUVglu, 0.66 for Kpat, 0.77 for MRpat, 0.71 for K5p, 0.73 for MR5p, 0.70 for K6p, and 0.78 for MR6p. No significant difference of area under the ROC curve between these methods was observed except the area between Kpat vs. MRpat (p<0.05). Conclusion: Quantitative methods did not improve diagnostic accuracy in comparison with nonkinetic methods. However, the clinical utility of these methods needs to be evaluated further in patients with low pretest likelihood of active inflammation or bronchoalveolar cell carcinoma.

• Korean Journal of Environment and Ecology
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• v.9 no.2
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• pp.197-201
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• 1996

A mixed forest community of Abies holophylla and broad-leaved trees in Odaesan National Park was studied to determine the adequate number of plots of shrub stratum for investigating forest community structure. Thirty 5m*5m plots were set up in the shrub stratum, and species-area curve and performance curve were made out. The minimum number of plots where a given percentage increase in number of plots produce in number of plots produced less than the same percentage increase in number of species was six. The minimum number of plots where a given percentage increase in number of plots produced less than the half of the percentage increase in number of plots was eleven. The minimum number of plots where the dominant species was distinguished from the subdominant species was five. The minimum numver of plots where the first subdominant species was distinguished from other subdominant species was ten. The diffrence of species diversity(H') between five or more plots and total thirty plots was less than 0.05. Similarity index was more than 70% between five or more plots and total thirty plots, and more than 80% between ten or more plots and total thirty plots. The conclusion is that the adequate number of 5m*5m plots for the shrub stratum was about 5 in general case and about 10 in case of requiring more accuracy.

• Journal of Korean Society of Forest Science
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• v.80 no.2
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• pp.210-219
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• 1991

This study is to diagnose the drought tolerance of twenty broad-leaved tree species by the pressure-volume(P-V) curves. As for the diagnosis of drought tolerance, the valuable water relations parameters obtained from P-V curves are the osmotic potential at full turgor, ${\Psi}_0{^{sat}}$, osmotic potential at incipient plasmolysis, ${\Psi}_0{^{tlp}}$, maximum bulk modulus of elasticity, $E_{max}$, and relative water content at incipient plasmolysis, $RWC^{tlp}$. Also, the figures related to the diagnosis of drought tolerance are the free water content (FWC) versus leaf water potential(${\Psi}_L$), volume-averaged turgor pressure ($P_{vat}$) versus leaf water potential (${\Psi}_L$), and H$\ddot{o}$fler diagram. In this study, the relatively high drought tolerant species are Fraxinus rhynchophylla, Quercus acutissima, Quercus serrata, Quercus aliena, and Populus alba${\times}$glandulosa ; the relatively low drought tolerant species are Fraxinus mandshurica, Betula platyphylla var. japonica, Populus euramericana, Kalopanax pictum, Carpinus loxiflora, Carpinus cordata, Prunus sargentii, Prunus leveilleana, and Cornus controversa ; medium species are Quercus mongolica, Acer mono, Acer triflorum, Acer pseudo-sieboldianum, Ulmus davidiana, and Zelkova serrata.

• Journal of Food Hygiene and Safety
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• v.32 no.3
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• pp.199-205
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• 2017

Although many PCR-based assays have been developed, the majority of rapid detection of Toxoplasma gondii in animal and their meat product has been dependent on immunogenic assays. Thus, there is still a need for more reliable PCR based detection method for T. gondii in retail meats. Recently, a 529-bp repeat element that exists in 200-300 copies per genome of T. gondii genome had been spotlighted for its usefulness as potential detection targers. In this study, the 529-bp repeat element was selected for real-time PCR to detect three types of T. gondii (type I, II and III). A primer pair targeting 82-bp of the 529-bp element detected all three types of T. gondii and showed high level of specificity against 14 different food-borne pathogens as well as 3 protozoan parasites such as Giardia lamblia, Cryptosporidium parvum and Entamoeba histolytica. Application of the new real-time PCR assay in meat samples showed improved detection sensitivity compared to the B1-gene targeted method suggesting potential new target for Toxoplasma gondii screening in retail meats.

• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.407-414
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• 2013

This study was conducted to classify forest cover types using the multivariate statistical analysis in the natural forest of western Mt. Jiri. On the basis of the vegetation data by point quarter sampling, the adopted analytical methods were species-area curve (SAC), hierarchical cluster analysis (HCA), indicator species analysis (ISA), and multiple discriminant analysis (MDA). SAC selected the outlier tree species which was likely to have no influence on the classification of forest cover types, excluded from all analytical process. Based on forest vegetative information, HCA classified the study area into 2 to 10 clusters and ISA indicated that the optimal number of clusters were seven. MDA was taken to test the clusters that classified with HCA and ISA. The seven clusters were classified appropriately as overall classification success were 91.3%. The classified forest cover types were named by the ratio of the dominant species in the upper layer of each cluster. They were (1) Quercus mongolica Pure forest, (2) Mixed mesophytic forest, (3) Q. mongolica - Q. serrata forest, (4) Abies koreana - Q. mongolica forest, (5) Fraxinus mandshurica forest, (6) Q. serrata forest, and (7) Carpinus laxiflora forest.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.5
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• pp.391-407
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• 1987

To understand the effects of the cooling water system of the power plant on the succession of sessile zoobenthos, a series of experiments were carried out at the cooling water system of Samchonpo Power Plant from Hay 1985 to May 1986. The lowest species diversity of the zoobenthos was observed at the discharge canal. This is probably caused by both increased velocity and temperature of circulating water. It is also noticeable that species composition of the zoobenthos, to a certain degree, was affected due to the impingement of meroplankton during the entrainment process. While the number of species attached on the experimental substrata installed in the thermally altered area is smaller than that in the intake canal, the biomass is increased as the increased temperature eliminates some species and in turn stimulates reproduction and growth of the others. It is interesting that relatively high similarity exists between the summer communities in the intake canal and the spring communities in the thermally altered area, and the same relationship is also found between the fall communities in the intake canal and the winter communities in the thermally altered area. Ecological index curves of the zoobenthos of the intake canal follows the fluctuation pattern of the thermally altered area in one or two months of elapsed time, probably due to temperature increase by the inflow of heated water discharged from the power plant.

• Journal of Korean Society of Forest Science
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• v.63 no.1
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• pp.28-34
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• 1984

This study was to elucidate the relation between the water relations parameters obtained from P-V curves and stomatal closure. The results obtained are as follows: 1) The water potential at incipient plasmolysis obtained from P-V curves was similar to the water potential at critical stomatal closure. 2) The critical stomatal closure of sun leaves appear at -21 bar (-17 bar, shade leaves) in Pinus koraiensis, -20 bar in Pinus rigida, -22 bar in Pinus densiflora, and -24 bar in Larix leptolepis. On a relative water content basis, the critical stomatal closures of sun leaves appear at 85% (82%, shade leaves) in Pinus kordiensis, 77% in Pinus ragida, 85% in Pinus densiflora, and 70% in Larix leptolepis. 3) The incipient stomatal closures of sun leaves appear at -14 bar (-12 bar, shade leaves) in Pinus koraiensis, -10 bar in Pinus rigida, -15 bar in Pinus densiflora, and -6 bar in Larix leptolepis. On a relative water content basis, the incipient stomatal closures of sun leaves appear at 90% in Pinus koraiensis, 93% in Pinus rigida, 90% in Pinus densiflora, and 93% in Larix leptolepis. 4) The leaf conductance was increased by increase in volume-averaged turgor pressure was linearly increased by increase in relative water content.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.707-711
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• 2007

낙동강과 밀양강의 합류지점에 위치한 김해시 딴섬 지역의 지표면하 $25{\sim}35\;m$ 구간에 형성되어 있는 고투수성 충적층 내 염소이온의 수리분산특성을 연구하기 위한 수렴흐름 추적자시험(convergent flow tracer test)이 수행되었다. 추적자로는 IW-1공과 IW-2공에서 각각 염소이온 5kg이 순간주입(instantaneous injection) 되었으며, PW공에서 일정한 양수율(2,500 m3 /day)로 채수하면서 염소이온농도를 관측하였다. 염소이온 주입 후 경과시간에 따른 염소이온농도 자료를 이용하여 농도이력곡선과 누적질량회수곡선이 산출되었으며, 관측된 염소이온농도의 정규분포를 검증하기 위한 일반통계분석이 수행되었다. 그리고, 농도이력의 증가/감소 구간에서의 함수를 추정하였으며, 두 시험에서 동일한 시간에 관측된 염소이온농도의 상관성이 분석되었다. 본 현장에서 수행된 추적자시험에 의한 종분산지수의 추정은 CATTI 코드(Sauty and Kinzelbach, 1992)에 의해 해석되었다. 추정된 종분산지수는 IW-1공과 PW공 구간에서는 0.4152 m, IW-2공과 PW공 구간에서는 0.4158 m 로서 매우 유사한 값으로 나타났다. 이는 추적자시험이 수행된 충적층에서의 용질이송이 방사상으로 비교적 균일함을 의미하는 것이다. 본 연구에서 수행된 추적자시험의 규모(2 m)를 Xu and Eckstein(1995)이 제시한 방정식에 대입하여 산정된 종분산지수는 0.0458 m 이었다. 이러한 결과는, 본 연구지역에서 수렴흐름 추적자시험에 의해 추정된 고투수성 충적층의 종분산지수가 일반적인 자연대수층에 비해 9.1배 정도 높다는 것을 의미한다. 이는 시험대수층의 투수성이 매우 높아 염소이온의 용질이송이 매우 빠르게 발생되었기 때문이다. 본 연구에서 추정된 종분산지수를 Gelhar et al.(1992)의 연구 결과와 비교 분석한 결과에서도 시험규모에 비해 매우 높은 수리분산이 발생된 것으로 나타났다. 그리고 염소이온의 확산면적을 추정하기 위해, 수렴흐름 추적자시험에 의한 종분산지수와 시험대수층의 평균선형유속을 이용하여 종분산계수를 구하였다. 현장에서 수행된 양수시험에 의한 평균선형유속 22.44 m/day와 평균 종분산지수 0.4155 m를 적용하여 산정된 종분산계수는 $9.32\;m^2/day$이었다. 따라서, 시험부지 내 충적층에서 일정한 양수율$(2,500\;m^3/day)$로 지하수를 개발할 시에 양수정 주변지역으로 유입되는 염소이온의 확산면적은 1일 $9.32\;m^2$ 정도일 것으로 나타났다.

• Journal of Korean Society of Forest Science
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• v.85 no.4
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• pp.557-564
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• 1996

Based on stem analysis as well as branch analysis data of each tree from 8 plots of circle clear-cutting and 1 biomass plot in Changbai Mountain area, located in Northeast of China, the effective crown form of Changbai larch(Larix olgensis H.) plantation were studied by using the approach of crown curve. The results indicated that the cross-section forms of effective crown were stable and showed approximate circle for different tree size. Because the effective crown was on upper position of the canopy and its form reflects crown architecture under non-competition condition, the architecture is mainly affected by species hereditary feature. Therefore, for the specified species the effective crown form was thought to be relatively stable. The effective crown form of tree was neither related to the tree size within stand nor to the stand condition for different stand. The total effective crown curve of larch plantation could be characterized by using mean effective crown taper.