• Economic and Environmental Geology
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• v.45 no.1
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• pp.9-21
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• 2012

In this study, we investigated the chemical characteristics of soils collected from the several deserts and loess in China known as the typical source areas of Asian dust (the Taklamakan desert, the Alashan desert, the Ordos desert and the Loess Plateau). Based on our analysis, we examined the possibility of adverse effects on environments and human health. In each desert and loess, major elemental compositions of soils did not show large variations, implying that the long-periodic mixing of soils in each area made their chemical compositions homogeneous. Minor elements of soils in each desert and loess showed more complicated patterns with strong correlations each other (e.g., Cr, Cu, As, Co, Ni, V, Y, Sc, Sn, Pb, Zn, Cd, Cs, Li, Th, U). These results thus enable us to discriminate the soil of the Loess Plateau from those of the other deserts in China. The results of sequential extraction experiments for soils showed that the chemical speciation of Fe was dominant in residual fraction (>85%) in all deserts and loess, but the fractions of Mn and Ca chemical speciations were very different in each area. In the case of Mn, the fraction of amorphous Fe-Mn hydroxides (55.4%) in the Central Loess Plateau and the carbonate fraction (33.8%) in Taklamakan desert were higher as much as 2 to 5 times than other deserts. The chemical speciations of Ca are dominant in carbonate fraction in Taklamakan (75.9%) and Alashan (50.5%) deserts, but carbonate fractions of Ca in the Loess Plateau and Ordos deserts were low (6.6% and 2.1%, respectively). According to the mobility of trace elements inferred from the results of sequential extraction procedure, we could classify them into five groups, and the mobility of Cd, Pb and Cu are more than 87%, 33% and 30%, respectively. Therefore, Cd, Pb and Cu in soils of deserts and loess could be easily dissolved when interacted with surface water. As such, they could give adverse effects on surficial environments and human health.

• Radiation Oncology Journal
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• v.11 no.2
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• pp.259-265
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• 1993

Between January 1985 and July 1992, 52 patients with locally advanced nasopharyngeal carcinoma were studied retrospectively for the effectiveness of sequential chemotherapy and radiation therapy. The male to female ratio was 3.3:1 with a median age of 41 years. Forty patients had squamous cell carcinoma and the remaining 12 had undifferentiated carcinoma. Seven patients had stage III disease and the remainder had stage IV disease at time of presentation. All patients were treated two courses of chemotherapy followed by radiation therapy. Chemotherapy consisted of either CVB (cisplatin, vincristine and bleomycin) or CF (cisplatin and 5-FU). Total radiation dose to the primary site ranged from 6000 cGy to 7500 cGy. Neck nodes were given booster treatment to maximum of 7000 cGy, depending on the extent of disease. Local control, overall survival and disease-free survival rates were analyzed. The complete response (CR) rate to chemotherapy was $15\%$ and the partial response (PR) rate was $46\%,$ for overall major response rate of $61\%.$ The CR rate was $87\%$ after radiation therapy. Median follow-up time was 51 months. The overall survival and disease-free survival rates at 36 months were $54\%\;and\;49\%,$ respectively. Median time to relapse was 15 months. The patterns of initial relapse in CR patients was as follows: locoregional failure only, 12 patients; distant metastasis only,11: both,2. Cox's multivariate regression model revealed that nodal status was the single most important independant prognostic factor influencing disease-free survival (p=0.001). Comparision of these results with other published reports with radiation therapy alone showed that a high rate of initial response to chemotherapy did not translate into local control or survival. At present time radiation therapy alone remains the standard treatment for locoregional cancer of the nasopharyngeal cancer. More controlled clinical trials must be completed before acceptance of chemotherapy as a part of treatment of advanced nasopharyngeal carcinoma.

• Korean journal of applied entomology
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• v.54 no.4
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• pp.401-407
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• 2015

This study describes the development of a method for monitoring Aphis gossypii in greenhouse cucumber fields that was used during 2013 and 2014. The dispersion pattern of A. gossypii was determined by commonly used methods: Taylor's power law (TPL) and Iwao's patchiness regression (IPR). The sample unit was determined by linear regression analysis between mean density of sample unit versus whole plant. The optimum sample unit for different plant growth stages was two leaves (median and the lowest + 1 leaf) when the total number of leaves was less than nine, and three leaves (4th, 7th from canopy, and the lowest +1 leaf) when the total number of leaves was greater than nine. A. gossypii showed an aggregated distribution pattern, as the slopes of both TPL and IPR lines were greater than 1. TPL provided a better description of the mean-variance relationship than did IPR. The slopes and intercepts of TPL and IPR from leaf samples did not differ between the surveyed years. Fixed precision levels (D) for a sequential sampling plan were developed using Green's and Kuno's equations based on the number of aphid in a leaf sample. Green's method was more efficient than Kuno's to stop sampling. The number of samples needed to estimate the density of A. gossypii increased at higher D levels and lower mean densities. The cumulative number of aphids needed to stop sampling increased at higher D levels and with fewer plants sampled. Thus to estimate 10 aphids per leaf, 13 plants needed to be sampled, and the cumulative number of aphids to stop sampling was 131.

• Analytical Science and Technology
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• v.24 no.2
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• pp.78-84
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• 2011

The fragmentation patterns of a serine protease inhibitor, camostat, and its degradation product, 4-(4-guanidinobenzoyloxy)phenylacetic acid (GBPA), were for the first time investigated by a triple quadrupole tandem mass spectrometry equipped with an electrospray source (ESI-MS/MS) in positive and/or negative ion mode under collision-induced dissociation (CID). The positive CID spectrum of camostat showed distinctly that the single bond (C-O) cleavage between carbonyl group and oxygen atom of the ester bonds of the compound favorably occurred and then the loss of N,N-dimethylcarbamoylmethyl group was more susceptible than that of guanidine moiety. In the positive ion CID spectrum of GBPA, the initial cleavage between the carbonyl group and oxygen atom of 4-guanidinobenzoyloxy group also occurred, yielding the most abundant fragment ion at m/z 145. On the other hand, the negative CID spectrum of GBPA characteristically showed the occurrence of the most abundant peak at m/z 226 resulting from the sequential neutral losses of $CO_2$ and HN=C=NH from the parent ion at m/z 312.

• The Korean Journal of Pesticide Science
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• v.21 no.1
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• pp.42-48
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• 2017

This study was conducted to compare the effect of bagging technique on the presence of pesticide residues in various parts of grape fruit (whole fruit, pulp and peel). The tested pesticides were diluted at 2,000 times and sprayed three times onto the crops at an interval of seven days and then they were collected at 0, 1, 3, 5 and 7 days after final application. Later, bagging/non-bagging samples were pre-treated with fruit, pulp and peel samples, respectively. Thiacloprid and lufenuron were not detected in any of the bagging samples. The thiacloprid residues of non-bagging samples in whole, peel and pulp samples were 0.47-1.09, 0.18-0.33 and 1.24-1.67 mg/kg, respectively. The lufenuron residues of non-bagging samples in whole fruit, peel and pulp samples were 0.16-0.62, < LOD-0.08 and 0.85-1.48 mg/kg, respectively. The biological half-lives of thiacloprid and lufenuron in whole fruit, peel and pulp of non-bagging samples were 5.7, 15.1 and 7.8 days and 4.0, 9.4 and 2.6 days, respectively. While the unbagged samples showed a sequential decrease in pesticide residues, this study concludes that bagging would be an effective method to protect the presence of thiacloprid and lufenuron residues in grape fruits.

• Korean journal of applied entomology
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• v.56 no.3
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• pp.309-314
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• 2017

Sampling plan using yellow sticky traps for the major strawberry flying pests - western flower thrips Frankliniella occidentalis adults, cotton aphid Aphis gossypii alate and greenhouse whitefly Trialeurodes vaporarium adults was developed to determine the initial occurrence time. The analyzed trap data were obtained from three commercial strawberry greenhouses for the whole growing season (September to May of the following year) during 2013 to 2017 in Jeju province. Three flying pests showed the aggregated distribution patterns resulted from commonly used regression techniques - Taylor's power law and Iwao's patchiness regression. Taylor's power law was better description of mean-variance relationship of the western flower thrips and the cotton aphid than Iwao's patchiness regression, otherwise greenhouse whitefly was better described by Iwao's patchiness regression. There were highly significant correlated among mean density per trap, maximum density and proportion of traps with more than 10 individuals. To estimate 4.0 heads of mean density per trap, the minimum number of traps were required 13 traps for western flower thrips, 11 traps for cotton aphid and 10 traps for greenhouse whitefly. The sequential sampling plans at the fixed precision level 0.25 were developed using parameters of Taylor's power law for western flower thrips and cotton aphid, and of Iwao's patchiness regression for greenhouse whitefly.

• Journal of the Korean earth science society
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• v.32 no.6
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• pp.525-536
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• 2011

In any applications using various types of spatial data, it is very important to account for the scale differences among available data sets and to change the scale to the target one as well. In this paper, we propose to use a geostatistical downscaling approach based on vaiorgram deconvloution and block simulation to generate fine-scale categorical thematic maps from coarse-scale fraction data. First, an iterative variogram deconvolution method is applied to estimate a point-support variogram model from a block-support variogram model. Then, both a direct sequential simulation based on area-to-point kriging and the estimated point-support variogram are applied to produce alternative fine-scale fraction realizations. Finally, a maximum a posteriori decision rule is applied to generate the fine-scale categorical thematic maps. These analytical steps are illustrated through a case study of land-cover mapping only using the block fraction data of thematic classes without point data. Alternative fine-scale fraction maps by the downscaling method presented in this study reproduce the coarse-scale block fraction values. The final fine-scale land-cover realizations can reflect overall spatial patterns of the reference land-cover map, thus providing reasonable inputs for the impact assessment in change of support problems.

• The Journal of the Acoustical Society of Korea
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• v.24 no.1
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• pp.29-37
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• 2005

This paper proposes an automatic genre classification system for Korean traditional music. The Proposed system accepts and classifies queried input music as one of the six musical genres such as Royal Shrine Music, Classcal Chamber Music, Folk Song, Folk Music, Buddhist Music, Shamanist Music based on music contents. In general, content-based music genre classification consists of two stages - music feature vector extraction and Pattern classification. For feature extraction. the system extracts 58 dimensional feature vectors including spectral centroid, spectral rolloff and spectral flux based on STFT and also the coefficient domain features such as LPC, MFCC, and then these features are further optimized using SFS method. For Pattern or genre classification, k-NN, Gaussian, GMM and SVM algorithms are considered. In addition, the proposed system adopts MFC method to settle down the uncertainty problem of the system performance due to the different query Patterns (or portions). From the experimental results. we verify the successful genre classification performance over $97{\%}$ for both the k-NN and SVM classifier, however SVM classifier provides almost three times faster classification performance than the k-NN.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.5
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• pp.882-895
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• 1997

Changes in the benthic communities have been studied to investigate the environmental effects before and after the construction of Shihwa Dike in the West coast of Korea. It is suggested that sequential changes in macrofaunal assemblages progressed in two sucressional directions. In the Shihwa lake under the influence of organic enrichment. First, the appearance of 'azoic tone' or 'grossly polluted zone' developed in the area of less than 6 m in depth resulted from the severe dissolved oxygen depletion due to the eutrophication from the increased organic loading. Second, the 'polluted zone' characterized by the proliferation of the opportunistic species in organically enriched area, was found in the vicinity of the industrial discharges and nearby fluvial inputs. This benthic community succession in the Shihwa lake seemed to be caused by the various ecological events such as an eutrophication in this organically enriched environment after construction of the dike and other physico-chemical parameters like salinity and dissolved oxygen in the bottom water, which may be influenced by the irregular surface water discharge and dilution by outer seawater inflow through the water gate of the dike. On the other hand, the benthic communities in the outside of the dike showed that the species richness was more than doubled and the abundance increased almost seven times more than that before the dike construction. This may be a typical characteristics of the initial phase in benthic eutrophication, suggesting that an increased organic input area may have been reponsible for this faunal change in the study area.

• Journal of Korea Water Resources Association
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• v.47 no.3
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• pp.223-235
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• 2014

In recent, the various methods to predict the hydrological impacts due to climate change have been developed and applied. Especially the trend analysis using observed and future hydrological data has been performed than ever. Parametric or non-parametric tests can be applied for a trend analysis. However, the non-parametric tests have been commonly used in the case of trend analysis using hydrological data. Therefore, the two types of non-parametric tests, Mann-Kendall (MK) test and Spearman Rho (SR) test, were used to detect the trend in the observed and future rainfall data that were collected from the Nakdong River basin. Also, the Pre-Whitening (PW) and the Trend Free Pre-Whitening (TFPW) as the pre-process of the trend analysis were performed. Also, the result of trend analysis suggest that those pre-processes have a statistically significant effect. Additionally, the Sequential Mann-Kendall (SMK) was used to reveal the beginning point of a trend in the observed and future rainfall data in the Nakdong River basin. The rainfall patterns in most rainfall gauges using the observed rainfall show the increasing trend and the abrupt changes in the specific months (from April to May and September to October). Also, the beginning point of the trend is brought forward by several months when climate change is accelerated. Finally, the results of this study can provide the useful background for the research related to climate change and water resources planning in the Nakdong River basin.