• Korean Journal of Soil Science and Fertilizer
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• v.50 no.2
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• pp.115-126
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• 2017

There is an increasing concern over arsenic (As) contamination in rice. This study was conducted to develope a prediction model for As uptake by rice based on the physico-chemical properties of soil. Soil and brown rice samples were collected from 46 sites in paddy fields near three different areas of closed mines and industrial complexes. Total As concentration, soil pH, Al oxide, available phosphorus (avail-P), organic matter (OM) content, and clay content in the soil samples were determined. Also, 1.0 N HCl, 1.0 M $NH_4NO_3$, 0.01 M $Ca(NO_3)_2$, and Mehlich 3 extractable-As in the soils were measured as phytoavailable As concentration in soil. Total As concentration in brown rice samples was also determined. Relationships among As concentrations in brown rice, total As concentrations in soils, and selected soil properties were as follows: As concentration in brown rice was negatively correlated with soil pH value, where as it was positively correlated with Al oxide concentration, avail-P concentration, and OM content in soil. In addition, the concentration of As in brown rice was statistically correlated only with 1.0 N HCl-extractable As in soil. Also, using multiple stepwise regression analysis, a modelling equation was created to predict As concentration in brown rice as affected by selected soil properties including soil As concentration. Prediction of As uptake by rice was delineated by the model [As in brown rice = 0.352 + $0.00109^*$ HCl extractable As in soil + $0.00002^*$ Al oxide + $0.0097^*$ OM + $0.00061^*$ avail-P - $0.0332^*$ soil pH] ($R=0.714^{***}$). The concentrations of As in brown rice estimated by the modelling equation were statistically acceptable because normalized mean error (NME) and normalized root mean square error (NRMSE) values were -0.055 and 0.2229, respectively, when compared with measured As concentration in the plant.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.5
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• pp.2349-2359
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• 2013

The purpose of this study was to predict the factors which are related to the intention and behaviour for breast self-examination (BSE) of middle aged women using the theory of planned behavior (TPB). A survey using a structured questionnaire was conducted wih 217 middle aged women. BSE behaviour was assessed at 1-month follow-up. The overall fit of the structural model to the date was acceptable(${\chi}^2$=1246.6(p<.001), ${\chi}^2$/df=2.72, CFI=.831, TLI=.817, RMSEA=.089). The BSE behavior rate within one month was 56.2%. The TPB explained 43.9% of the variance in BSE intentions and 10.9% of the variance in BSE behavior. The subjective norm(${\beta}$=.364, p<.001) and the perceived behavioral control(${\beta}$=.553, p<.001) both positively influenced the behavioral intention, and the behavioral intention(${\beta}$=.768, p<.01) positively influenced the behavior. This study shows the model's applicability in explaining BSE behavior of middle aged women, and suggests that health intervention programs should focus on strengthening the intention for the promotion of BSE behavior.

• Environmental and Resource Economics Review
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• v.15 no.4
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• pp.591-642
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• 2006

This paper intends to analyze economic impacts of commitment period and initial allocation in emissions trading using computable general equilibrium (CGE) modeling. The fully dynamic CGE model with perfect foresight assumption is employed to illustrate (i) how a model displays economic impact of $CO_2$ regulation upon different commitment periods: one-year budget clearing vs. 5-year commitment period, (ii) how major 8 energy-intensive industries respond to different ways to allocate initial allowances. According to the results of the analysis, it IS found that market players are motivated to bank the permits and tend to sell permits in earlier stage and to buy permits in later stage of commitment period. This implies that banking allows permit trading within a commitment period, which supports the conclusions of Kling and Rubin (1997). Other findings are related to efficiency. That is, emissions trading surpasses command and control, in terms of economic efficiency and longer terms of commitment period converge on lower permit price, In long term, initial allocation based on value-added performs the lowest GDP loss among different initial allocations.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.286-292
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• 2005

This study is to investigate the industrial boiler which can be significantly affected by the restriction of NOx. Note that the application of SNCR method to industrial boiler is usually blown as not feasible due to the insufficient residence time for proper mixing. The purpose of this study is to investigate the applicability of the SNCR system application to the industrial boiler, which produces 40 tons of steam per hour using heavy oil. For the industrial boiler with 3-D rectangular coordinate, the general coding are made fur various turbulence modeling such as turbulent flow, turbulent fuel combustion, thermal NO formation and destruction together with the NO reaction with reducing agents. Further, the incorporation of drop trajectory model is successfully made in 3-D rectangular coordinate with Lagrangian frame and the main swirl burner effect on the characteristics of flame is considered. As expected a short flame was created and thereby NOx is removed more efficiently by increasing the proper region of temperature for NO reduction reaction. The validation of program was made successfully by the comparison of experimental data. Based on the reliable calculation results, the SNCR method in a industrial boiler shows the possibility as one of viable NO reduction method by the use of well designed mixing air of reducing agent.

• Journal of Korea Water Resources Association
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• v.45 no.12
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• pp.1259-1273
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• 2012

In this study, a watershed-based surface water and groundwater integrated model, SWAT-MODFLOW was used to quantify the stream flow depletion due to groundwater pumping for the Sinduncheon watershed. Complex water use conditions such as water taken from a stream, sewage disposal release, irrigation from agricultural reservoir, groundwater pumping were considered for simulations. In particular, the model was revised to reflect the effects of reservoir operation and return flow from the used groundwater on streamflow variation. The simulated results showed that the groundwater pumping at current status has induced the decrease of more than 10% in annual average streamflow and 40% in drought flow at the outlet of the Sinduncheon watershed, The simulated results also revealed that the vast water withdrawals at green house areas during winter season have dramatically changed streamflow from April to June. The streamflow depletion was mainly attributed to pumping wells located within the distance of 300 m from the stream for Sinduncheon watershed.

• The Korean Journal of Applied Statistics
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• v.33 no.6
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• pp.823-832
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• 2020

The analgesic effects of music in people with glasses on perceived pain through cold-pressor task (CPT) is assessed based on three-sequence, three-period, crossover trial with three treatment conditions(music-listening, news-listening, and no-sound) to each subject. Fifty subjects are divided into three sequence groups by randomization, and CPTs under the pre-assigned treatment conditions at each period are performed. Pain responses after each CPT, subjects' pain tolerance (PT) in time scale and pain intensity (PI) and pain unpleasantness (PU) in visual analog scale (VAS) are measured. After classifying the group by whether or not to wear glasses, which is the phenotype of the myopia gene, pain responses are compared by F-tests and Tukey's multiple comparisons. CPT pain responses in group with glasses during the music intervention are significantly different from responses during the news intervention and the control conditions, respectively. This study investigates the pain responses of music intervention in the group wearing glasses, which can be seen as a phenotype of the nearsighted gene, and this result would play a role in explaining the biopsychosocial model of the pain mechanism.

• Natural Product Sciences
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• v.27 no.2
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• pp.86-98
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• 2021

This study was designed to characterize the effect of ginsenoside-Rg2 (Rg2), one of panaxatriol saponins isolated from Korean ginseng root, on the release of catecholamines (CA) in the perfused model of the rat adrenal medulla, and also to establish its mechanism of action. Rg2 (3~30 µM), administered into an adrenal vein for 90 min, depressed acetylcholine (ACh)-induced CA secretion in a dose- and time-dependent manner. Rg2 also time-dependently inhibited the CA secretion induced by 3-(m-chloro-phenyl-carbamoyl-oxy)-2-butynyltrimethyl ammonium chloride (McN-A-343), 1.1-dimethyl-4-phenyl piperazinium iodide (DMPP), and angiotensin II (Ang II). Also, during perfusion of Rg2, the CA secretion induced by high K⁺, veratridine, cyclopiazonic acid, methyl-1,4-dihydro-2,6-dimethyl-3-nitro-4-(2-trifluoro-methyl-phenyl)-pyridine-5-carboxylate (Bay-K-8644) depressed, respectively. In the simultaneous presence of Rg2 and N^ω-nitro-L-arginine methyl ester hydrochloride ʟ-NAME), the CA secretion induced by ACh, Ang II, Bay-K-8644 and veratridine was restored nearly to the extent of their corresponding control level, respectively, compared to those of inhibitory effects of Rg2-treatment alone. Virtually, NO release in adrenal medulla following perfusion of Rg2 was significantly enhanced in comparison to the corresponding spontaneous release. Also, in the coexistence of Rg2 and fimasartan, ACh-induced CA secretion was markedly diminished compared to the inhibitory effect of fimasartan-treated alone. Collectively, these results demonstrated that Rg2 suppressed the CA secretion induced by activation of cholinergic as well as angiotensinergic receptors from the perfused model of the rat adrenal gland. This Rg2-induced inhibitory effect seems to be exerted by reducing both influx of Na⁺ and Ca²⁺ through their ionic channels into the adrenomedullary cells as well as by suppressing Ca²⁺ release from the cytoplasmic calcium store, at least through the elevated NO release by activation of NO synthase, which is associated to the blockade of neuronal cholinergic and AT₁-receptors. Based on these results, the ingestion of Rg2 may be helpful to alleviate or prevent the cardiovascular diseases, via reduction of CA release in adrenal medulla and consequent decreased CA level in circulation.

• Asia Marketing Journal
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• v.16 no.1
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• pp.21-33
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• 2014

When the negative event is published, the company tends to go through the negative impact on the firm performance. Especially, with the SNS, the negative event is instantly spread on indefinite region so the impact seems bigger than the period before the SNS media appearance. It seems that everyone considers the SNS media impact on the firm performance quite big. However, there has been no empirical study on the impact comparison on the firm performance between pre and post SNS media occurrence periods. This study tries to empirically compare the impact of the negative event on the firm performance between pre and post SNS media appearance. Our study starts fromthe basic but not verified question; Does really the negative event have more negative impact in the post-SNS-occurrence period than in the pre-SNS-occurrence period? In order to examine the impact of the negative publicity on firm performance in two eras, pre and post SNS media appearance, we used CAR (Cumulative Abnormal Resturns) model. By using this model, we could verify the statistical significance of cumulative abnormal returns in market between before and after the events. For event samples, we focused on food manufacturers and collected the negative events from 1991 to 2003 for pre-SNS occurrence period, and from 2010 to 2013 for post-SNS occurrence period. Based on the listed food companies at KOSPI, we researched Naver News Library (newslibrary.naver.com) and Naver News (news.naver.com) for all the individual negative events published for both periods. Firm returns data were collected from TS 2000 (KOCO Info) and market portfolio data were collected from KRX Exchange. Through our empirical analysis, our finding is interesting to note that the type of events differently influences on the firm performance. With the SNS, the health-related events have influence on the firm performance 'after the event day' whereas the company behavior trust events have influence 'before the event day'. Our findings have implications for management. When a negative event directly related to or threatening customers or their life such as health, it is crucial to fix up the situation right after the event occurs. On the other hand, when a negative event is not publicly available information such as company behavior trust, it is important for marketers to strengthen the firms' trust reputation and control the bad WOM before the event.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.29 no.6
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• pp.305-314
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• 2017

Ocean wave energy harvesting is still too expensive despite developing a variety of wave energy converter (WEC) devices. For the cost-effective wave energy harvesting, it can be an effective measure to use existing breakwaters or newly installed breakwaters for both wave control and energy harvesting purposes. In this study, we investigated the functionality of both breakwater and wave-power generator for the oscillating water column (OWC)-type wave energy converter (WEC) installed in a pneumatic floating breakwater, which was originally developed as a floating breakwater. In order to verify the performance of the breakwater as a WEC, the air flow velocity from air-chamber to WEC has to be evaluated properly. Therefore, air flow velocity, wave transformation and motion of floating structure was numerically implemented based on BEM from linear velocity potential theory without considering the compressibility of air within the chamber. Air pressure, meanwhile, was assumed to be fluctuated by the motions of structure and the water level change within air-chamber. The validity of the obtained values can be determined by comparing the previous results from the numerical analysis for different shapes. Based on numerical model results, wave transformation characteristics around OWC system mounted on the fixed and floating breakwaters, and motions of the structure with air flow velocities are investigated. In summary, all numerical results are almost identical to the previous research considering air compressibility. Therefore, it can be concluded that this analysis not considering air compressibility in the air chamber is more efficient and practical method.

• The Journal of Korean society of community based occupational therapy
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• v.6 no.1
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• pp.41-48
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• 2016

Objective : We tried to know the improvement and neurological effect of diabetes when the complex exercise training was applied on diabetes that delayed the recovery of the ischemic brain injury. Methods : We performed this study in a animal lab which located in Gyengsangbukdo. We used 10 diabetes rats with ischemic brain injury, which is induced by STZ. We applied the complex exercise training on the rats for 4 weeks. We executed the maze test to confirm the recovery of the brain function and checked the blood sugar to know the improvement. Results : As a result of applying the complex exercise on diabetes rats with ischemic brain injury, there was a significant reduce of error and escape time in 3 weeks and 1 weeks, respectively. There was no difference of the blood sugar in control but there was a significant improvement in experiment group after applying the exercise training in 4 weeks. Conclusion : The senile disease like stroke and diabetes was increased currently. It is important for rehabilitation to improve the quality of life during the remainder of their life. In the study, we've known the improvement of diabetes and the recovery of the brain function when the complex exercise training was applied the rats with both diabetes and the ischemic brain injury.