• Earthquakes and Structures
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• 제14권2호
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• pp.143-153
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• 2018

Correlation among different factors must be considered for selection of influencing factors in safety monitoring of high dam including positive correlation of variables. Therefore, a new factor selection method was constructed based on Copula entropy and mutual information theory, which was deduced and optimized. Considering the small sample size in high dam monitoring and distribution of daily monitoring samples, a computing method that avoids causality of structure as much as possible is needed. The two-dimensional normal information diffusion and fuzzy reasoning of pattern recognition field are based on the weight theory, which avoids complicated causes of the studying structure. Hence, it is used to dam safety monitoring field and simplified, which increases sample information appropriately. Next, a complete system integrating high dam monitoring and uncertainty prediction method was established by combining Copula entropy theory and information diffusion theory. Finally, the proposed method was applied in seepage monitoring of Nuozhadu clay core-wall rockfill dam. Its selection of influencing factors and processing of sample data were compared with different models. Results demonstrated that the proposed method increases the prediction accuracy to some extent.

• 지구물리와물리탐사
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• 제7권1호
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• pp.25-32
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• 2004

We have carried out laboratory measurements of P-wave velocity and deformation strain during $CO_2$ injection into a porous sandstone sample, in dry and water-saturated conditions. The rock sample was cylindrical, with the axis normal to the bedding plane, and fluid injection was performed from one end. Using a piezoelectric transducer array system, we mapped fluid movement during injection of distilled water into dry sandstone, and of gaseous, liquid, and supercritical $CO_2$ into a water-saturated sample. The velocity changes caused by water injection ranged from $5.61\;to\;7.52\%$. The velocity changes caused by $CO_2$ injection are typically about $-6\%$, and about $-10\%$ for injection of supercritical $CO_2$, Such changes in velocity show that the seismic method may be useful in mapping $CO_2$ movement in the subsurface. Strain normal to the bedding plane was greater than strain parallel to the bedding plane during $CO_2$ injection; injection of supercritical $CO_2$ showed a particularly strong effect. Strain changes suggest the possibility of monitoring rock mass deformation by using borehole tiltmeters at geological sequestration sites. We also found differences associated with $CO_2$ phases in velocity and strain changes during injection.

• 한국물환경학회지
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• 제29권4호
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• pp.568-573
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• 2013

In this study, we conducted whole effluent toxicity (WET) proficiency testing based on the results which $EC_{50}$ value of 3 types (A, B, C) unknown samples calculated from 32 water quality measurement agencies in Korea. WET proficiency testing was expected to their improve of analysis skill and ensure reliability of analysis results. Ultimately, it is intended to promote the reliable enforcement of WET. WET proficiency testing was evaluated using the z-score, robust z-score and the results showed that 30 participating agencies were "compliance". In addition, $EC_{50}$ values of "unknown sample A" were the normal distribution. Therefore, "unknown sample A" was considered as the most suitable standard toxicity substance.

• 한국환경과학회지
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• 제8권5호
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• pp.601-605
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• 1999

This study has been performed to evaluate mineral water quality by using four parameters [Mg]/[Ca], [Na]/[K], [Mg]+[Ca]/[Na]+[K] and total hardness(as CaCO3 mg/ℓ). The four parameters has been ploted in a general scale and logarithmic scale, respectively. The method of general scale is not applicable for evaluation on several parameters. Therefore, the logarithmic scale is applied instead to settle the problem. The evaluation of the water quality is based on standard sample S, and the results of the 6 domestics and 5 overseas sample evaluation are as follow. At present, evaluation of the water quality on the mineral water can be done by using four parameters calculated from only cation concentration printed on the bottle's marking.

• 한국재료학회지
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• 제15권3호
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• pp.209-215
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• 2005

Titanium dioxide films $(TiO_2)$ doped cobalt transition metal were prepared on titanium metal by water spray pyrolysis technique. Micro-morphology, crystalline structure, chemical composition and binding state of sample groups were evaluated using field emission scanning microscope(FE-SEM), X-ray diffractometer(XRD), Raman spectrometer, X-ray photoelectron spectrometer(XPS). $TiO_2$ films of rutile structure were predominately formed on all sample groups and $Ti_2O_3$ oxide was coexisted on the surface of cobalt doped-sample groups. The optical absorption peaks measured by using UV-VIS-NIR spectrophotometer were observed at specific wavelength region in sample groups doped cobalt ion. This result could be analyzed by introducing crystal field theory.

• 한국식품영양과학회지
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• 제19권2호
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• pp.175-179
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• 1990

Investigations of skin stripping freezing and thawing conditions of common-European squid (Loigo vulgaris) were carried out. The most effective method of skin stripping was to immerse the sample at 5$0^{\circ}C$ for 10-15 minutes in fresh water or salt solution(5-10% w/v) Contact freezing and fresh water thawing method was found to be effective. The muscle structure of the sample thawed after contact freezing was almost the sample after contact freezing was almost the same as that of raw sample.

• 한국물환경학회지
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• 제31권6호
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• pp.610-618
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• 2015

This study was conducted to find out the influence of sample size (accumulated survey areas) on the seven biological indices of benthic macroinvertebrates. BMI, the index similar to Zeilika-Marvan’s saprobic index, tended to be independent on the variations of sample size. The other indices (Shannon-Weaver’s diversity, Margalef’s richness, Menhinick’s richness, Pielou’s evenness, and Lenat’s EPT index) showed the considerable variations along with the increase of sample size and environmental conditions. To get the appropriate index values, it should be sampled at least 6 replicates more based on 30×30cm Surber sampler. In addition, the habitat heterogeneity index of benthic macroinvertebrates suggested in this study, it will be able to be used for evaluating the heterogeneity of habitats.

• 한국연초학회지
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• 제22권1호
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• pp.91-98
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• 2000

This study was carried out to evaluate the uncertainty in the analysis of menthol content from the mentholated cigarette. Menthol in the sample cigarette was extracted with methanol containing an anethole as an internal standard, and then analyzed by gas chromatography. As the sources of uncertainty associated with the analysis of menthol, were the following points tested, such as the weighing of sample, the preparation of extracting solution, the pipetting of extracting solution into the sample, the preparation of standard solution, the precision of GC injections for standard & sample solution, the GC response factor of standard solution, the reproducibility of menthol analysis, and the determination of water content in tobacco, etc. For calculating the uncertainties, type A of uncertainty was evaluated by the statistical analysis of a series of observation, and type B by the information based on supplier's catalogue and/or certificated of calibration. Sources of uncertainty were subsequently included and mathematically combined with the uncertainty arising from the assessment of accuracy to provide the overall uncertainty. It was shown that the main source of uncertainty came from the errors in the reproducibility of menthol and water determination, the purity of menthol reference material in the preparation of standard solution, and the precision of GC injections for sample solution. The errors in sample weighing and volume measurement contributed relatively little to the overall uncertainty. The expanded uncertainty in the mentholated cigarettes, Korean and American brand, at 0.95 level of statistical confidence was $\pm$0.06 and $\pm$0.07 mg/g for a menthol content of 1.89 and 2.32 mg/g, respectively.

• 동국한의학연구소논문집
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• 제5권
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• pp.53-77
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• 1996

The purpose of this study is to observe the effect of Sayeuksan on serum reaction in $CCl^4$ treated rats. In this study the experimental rats divided four group (Control group, $CCl^4$ group, sayeuksan group, and shiho, kamcho group) Under the same condition control group were administered water, sample group were administered Sayeuksan for 8days. and then, both $CCl_4$ group and sample group were injeccted to abdomen with $CCl_4$ for 1days. The change of GOT GPT ${\gamma}$-GTP ALP LDH activity in blood serum. The obtained results are summarised as follows : 1. In the change of GOT GPT contents, as compared with control group sample group was significantly decreased. 2. In the change of ${\gamma}$-GTP contents as compared with control group, sample group was significantly decreased. 3. In the change of ALP contents, as compared with control group, sample group was significantly decreased. 4. In the change of LDH contents, as compared with contol group, sample group was significantly decreased.

• 한국물환경학회지
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• 제16권4호
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• pp.469-477
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• 2000

Bisphenol-A (BPA), a known endocrine disruptor, is a main building block of epoxy resin which is widely used as a coating agent in residential water storage tanks. Therefore, BPA leaching from the epoxy resin may have adverse effects on human health. The possibility of BPA leaching from three epoxy resins were tested with a modified KS D 8502 method at 20, 50, 75 and $100^{\circ}C$ in deionized water and the specified test water, respectively. BPA leached to the test water was identified using GC-MS and quantified with GC-FID after a sequential extraction and concentration. The results showed that BPA leaching has occurred in all three samples tested. The quantify of BPA leaching from unit area of epoxy resin coating was in the range of $10.677{\sim}273.120{\mu}g/m^2$ for sample A, 29.737~1734.045 for sample B and 52.857~548.778 for sample C depending on the test temperature, respectively. In general, the amount of BPA leaching increased as the water temperature increases. This result implies a higher risk of BPA leaching to drinking water during a hot summer season. In addition, microbial growth, measured by colony forming units, in epoxy coated water tanks was higher than that in a stainless steel tank suggesting that compounds leaching from epoxy resin may support the growth of microorganisms in a residential water holding tank.