• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.2D
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• pp.295-302
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• 2011

Ubiquitous is an information communication environment which peoples could connect on network without being conscious of the network and computer condition at anytime and anywhere. Presently, advanced technology, digital cities and eco-friendly cities using Ubiquitous technology are being focused through out the world. As recent information industry and communication technology have developed remarkably, studies on intelligent structures and structural maintenance methods by combining a general idea of connecting all objects on network by interpolating computers which is called Ubiquitous Computing, and USN(Ubiquitous Sensor Network) are being attempted. In this paper, a basic experiment on penetration of RF(Radio Frequency) sensor nodes using an experimental sample setting concrete and reinforcing bar as variables is studied to estimate the possibility of applying wireless sensor networks in structures. The spring of reinforcing bars, concrete thickness, intensity of radio frequency were set up as variables, transmitting and receiving distance were checked vertically and horizontally. Moreover, Spectrum Analyzer was used for checking the magnitude of the frequency used in order to measure the reduction of radio wave exactly. The radio wave reduction was numerically analyzed, and the influence of the wavelength was analysed as well. As a result, the penetration depth in concrete without reinforcing bars was 45cm, and in reinforced concretes which reinforcing bars placed at spacing of 5cm and 15cm, the penetration depth were 37cm and 45cm each. No influence on radio wave penetration depth were found when the spacing of reinforcing bars in the reinforced concrete structures becomes over 15cm.

• Culinary science and hospitality research
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• v.7 no.2
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• pp.49-70
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• 2001

The anchovy, Engraulis japonica, were prepared with two different saltconcentration of 20%, 10% which was added 2, 5, 8 and 10 % of grind garlic(LSA 1, 2, 3, 4) and garlic juice(LSB 1, 2, 3, 4), respectively. The changes of such factor during fermentation of anchovy as general composition, salt concentration, titrable acidity and sensory evolution were analyzed. In addition, chewiness, taste, garlic flavor and off-flavor wastested it's results were belived that the more garlic amounts added the more rotten smell has been disappeared. In the view of sensory perception. sample of 90 days fermentation is supposed as the best period of fermentation. The contents of moisture and crude fat decreased while, those of ash and crude protein were changes little during fermentation of low salted anchovy. Titrable acidity decreased in all experiment groups during anchovy fermentation, its contents at 30 days fermentation were ranged between 1.4~ 1.8g/100g, but it dramatically decreased to 0.6~l.1g/100g at 90 days fermentation.

• The Korean Journal of Mycology
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• v.12 no.4
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• pp.153-157
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• 1984

In order to investigate an etiological characteristics of the pepper anthracnose fungus infected with Collectotrichum dematium, this experiment was undertaken. Isolation percent of the fungus was 55.3% from the seed sample of Jewon and 0.3% from that of Eumsung Kun, according to seed health blotter method. Although the acervulus was similar to the known two Colletotricum species, C. acutatum and C. gloeosporioides, setae was not only straightly extended above the acervulus, but also shaped as falcate conidia ranging $12{\sim}31.2{\times}2.4{\sim}4.8{\mu}m$. Acervului of the fungus were evenly scattered on the surface of pepper seed coat, and caused seedling blight after seed germination. Pre-and post-emergence seedling blight as well as foliar lesion and fruit rot was confirmed by inoculating conidial suspension. No typical anthracnose sysmptom was obtained from soybean seedlings, welsch onion and spinach seedlings upon inoculation. Therefore, this fungus is said to the undescribed form species of the fungus of pepper in Korea (Colletotricum dematium f. sp. capsicum).

• The Korean Journal of Ecology
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• v.25 no.4
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• pp.253-259
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• 2002

Application of phytoremediation in the polluted area to remove undesirable materials is a complex and difficult subject without detailed investigation and experimentation. We investigated the accumulation patterns of cadmium and lead in plants naturally grown, the bioavailability of plants to accumulate these toxic metals and the responses of P. thunbergii to cadmium and lead. The soil samples contained detectable lead (＜$17.5_\mu$g/g), whereas cadmium was not detected in the soils of study area. The whole body of Persicaria thunbergii contained detectable lead (＜320.$8_\mu$g/g/g) but cadmium was detected only in the stem (＜7.$4_\mu$g/g/g) and root (＜10.$4_\mu$g/g/g) of P. thunbergii. Cadmium was not detected in Trapa japonica and Nymphoides peltata, whereas lead was detected in T. japonica (＜323.$7_\mu$g/g/g) and N. peltata (＜177.$5_\mu$g/g/g). Correlation coefficient between lead content in soil and in these plant samples represented positive correlation. The total content of lead in each plant sample increased in the order of N. peltata$\leq$P. thunbergii

• Journal of the Korean Data and Information Science Society
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• v.28 no.4
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• pp.831-841
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• 2017

The irrational number ${\pi}$ is defined as the ratio of circumference of a circle to its radius and always becomes constant. This article does Monte Carlo approximation of its value using the famous Buffon's needle experiment and shows that its convergence is not always proportional to the sample size. We also do Monte Carlo simulations to see the convergence of the computed ${\pi}$ values from the random walk series with independent normal increment. Finally we apply the theoretical derivation to various financial time series data such as KOSPI, stock prices of Korean big firms, global stock indices and major foreign exchange rates. The historical data shows that log transformed data random walk process but most of their first lagged data don't follow a normal distribution. More importantly the computed value from the ratio of the regression coefficient ${\pi}$ tend to converge a constant, unfortunately not ${\pi}$. Using this result we could doubt on the efficient market hypothesis, and relate the degree of the hypothesis with the amount of deviation of the estimated ${\pi}$ values.

• Korean Journal of Food Science and Technology
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• v.46 no.4
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• pp.446-455
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• 2014

In this study, we aimed to develop mixed grain-derived hard liquor with enhanced favor and taste. First, fermentation characteristics analysis according to the grain used showed that rice and adlay produced high alcohol outputs of 15.2% and 13.3%, respectively, while that of barley was low at 5.6%. In an experiment in which different amounts sorghum flour were added, the sample without sorghum flour showed an alcohol content of 19.0%. The effect of adding up to 7% ipkuk (koji) was examined in a sensory test. Comprehensive preference increased with increasing amounts of added ipkuk. Fermentation characteristics analyses of distilled liquor into which milled rice (5% degrees of milling of unpolished waxy rice) was added showed that alcohol content and acidity were not greatly affected by its addition. Finally, an analysis of aromatic ingredients showed that the percentage of ethyl palmitate, which produces a smooth aroma, was the highest in distilled liquor made of mixed grains.

• Environmental and Resource Economics Review
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• v.28 no.4
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• pp.645-673
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• 2019

The hypothetical nature of stated preferences can lead to a hypothetical bias that might work as a normative pressure, influencing survey responses. This paper aims to test the impact of social desirability bias by comparing economic estimates based on both subjective and objective valuation questions. The case study is about an urban riverine restoration project in Deajeon, South Korea. As valuation methods both contingent valuation and choice experiments were comparatively applied. Based on a nationally representative sample of 1,000 respondents, the test results offered contrasting conclusions between two test approaches. Accroding to the estimation results based on the conventional valuation, the marginal willingness to pay estimates are 10,500 KRW from CV; and 18,600 KRW for improving water quality, 2,200 KRW for the inside view, 8,900 KRW for the outside view, and 5,800 KRW for biodiversity from CE. A segmentation-based approach is a conventionally used method, which showed a limited impact of social desirability on willingness to pay estimates. The alternative parameterization-based approach measures a model-wide impact of social desirability, proving a significant bias. Although the study positioned a cheap-talk statement before the valuation section of the survey questionnaires, which might have pre-screened the bias, the overall implications of the results suggest a caution in reducing and observing hypothetical bias. There might remain a significant and substantial hypothetical bias even after cheap-talk, particularly in situations with strong social desirability, so that the potential role of objective valuation questions is guaranteed.

• Korean Journal of Oriental Medicine
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• v.15 no.3
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• pp.83-91
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• 2009

$\beta$-glucan is a fiber-type complex sugar (polysaccharide) derived from the cell wall of baker's yeast, oat and barley fiber, and many medicinal mushrooms, such as maitake. The primary uses of $\beta$-glucan are to enhance the immune system, to lower blood cholesterol levels and to treat tumor. $\beta$-glucan has no systemic toxicity in mice, therefore it needed clinical trail to prove efficacy and safety for human. The subjects total 56 healty volunteers were divided into two groups including taken $\beta$-glucan tablet group and placebo group. Subjects were taken two tablets per oral for 4 weeks. They had agreed to take part in this experiment, and didn't take any other clinical trail products. After 4 weeks blood of subjects were checked. The check list are TNF-$\alpha$, INF-$\gamma$, IL-2, IL-4, total WBC, differential WBC, RBC, hemoglobin, platelet, MCV, MCH, MCHC, HCT, Na, K, Ca, Cl, AST, ALT, ALP, $\gamma$-GTP, total protein, triglyceride, total cholesterol, total bilirubin, albumin, uric acid, creatinine, BUN, pH, protein, glucose, ketone body, blood, bilirubin. We evaluated efficacy by cytokines that compare before and after taking. Collected data were analyzed as two sample t-test, chi-square test and ANOVA using SAS V.9.1.This study results are that in TNF-$\alpha$ of $1^{st}$ efficacy measurement item, all of two groups figure were increased significantly compare to before figure. In IL4 of $2^{nd}$ efficacy measurement item, experimental group figure were decreased significantly but placebo group figure were increased. The conclusions show that based on the above results, $\beta$-glucan has favorable effect to enhance immune system, especially IL4 results showed that it has effect to improve the allergic immune system.

• The KIPS Transactions:PartB
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• v.15B no.1
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• pp.25-36
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• 2008

In this paper, we present a robust hand recognition approach to sudden illumination changes. The proposed approach constructs a background model with respect to hue and hue gradient in HSI color space and extracts a foreground hand region from an input image using the background subtraction method. Eighteen features are defined for a hand pose and multi-class SVM(Support Vector Machine) approach is applied to learn and classify hand poses based on eighteen features. The proposed approach robustly extracts the contour of a hand with variations in illumination by applying the hue gradient into the background subtraction. A hand pose is defined by two Eigen values which are normalized by the size of OBB(Object-Oriented Bounding Box), and sixteen feature values which represent the number of hand contour points included in each subrange of OBB. We compared the RGB-based background subtraction, hue-based background subtraction and the proposed approach with sudden illumination changes and proved the robustness of the proposed approach. In the experiment, we built a hand pose training model from 2,700 sample hand images of six subjects which represent nine numerical numbers from one to nine. Our implementation result shows 92.6% of successful recognition rate for 1,620 hand images with various lighting condition using the training model.

• Journal of Korea Water Resources Association
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• v.32 no.6
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• pp.751-762
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• 1999

In this study, a 1-D laboratory experiment was conducted to investigate the characteristics of transient unsaturated solute transport by using two kinds of soils of which properties were known by test. Especially the TDR method which is proposed in this study was used to measure water content and solute concentration. As results, in the transient flow, the wetting front moves down rapidly, and the distribution of solute concentration near the wetting front showed the similar type of the water content distribution(semi-bell type). A numerical model HYDRUS was used to compare with the experimental results. Numerical results for the water movement are similar to experimental result. However, numerical results of the distribution of solute concentration are more scattered than experimental results. It means that measured dispersivity, numerical dispersion, adsorption coefficient, and soil sample size etc. should be considered in order to determine the dispersivity used in the numerical model. The present measuring method was proved to be superior to other formula and to be an available method to apply to solute transport test. The measuring error of the developed method is estimated smaller than 10% while water content is larger than 0.15.