• Journal of Korean Society on Water Environment
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• v.37 no.2
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• pp.114-127
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• 2021

Water pollution in the lower reaches of the Namhan River is getting worse due to drought and a decrease in water quantity due to climatic changes and hence is affecting the water quality of Paldang Lake. Accordingly, we have used a water quality index (WQI) and statistical analysis in this study to identify the characteristics of the water quality in the lower reaches of the Namhan River, the main causes of water pollution, and tributaries that need priority management. Typically, 10 items (WT, pH, EC, DO, BOD, COD, SS, T-N, T-P, and TOC) were used as the water quality factors for the statistical analysis, and the matrix of data was set as 324 × 10·1. The correlation analysis demonstrated a strong correlation between Chemical Oxygen Demand (COD) and T-P with a high statistical significance (r=0.700, p<0.01). Furthermore, the result of principal component analysis (PCA) revealed that the main factors affecting the change in water quality were T-P and organic substances introduced into the water by rainfall. Based on the Mann-Kendall test, a statistically significant increase in pH was observed in SH-1, DL, SH-2, CM, and BH, along with an increase in WQI in SH-2 and SM. BH was identified as a tributary that needs priority management in the lower reaches of the Namhan River, with a "Somewhat poor" (IV) grade in T-P, "Fair" grade in WQI, and "Marginal" grade in summer.

• Journal of Korean Society for Quality Management
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• v.36 no.2
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• pp.20-27
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• 2008

Tolerance design has been identified as an important research area and a number of models have been proposed in the literature. This paper investigates the effect of limited capacity on tolerance design for products with nominal-the-best type (N-type) quality characteristics. The model is developed under the assumption that the reprocessed and nonreprocessed items are produced by the same manufacturing process and therefore their quality characteristics are identically and independently distributed. Profit models are constructed which involve four price/cost components; selling price, cost incurred by imperfect quality, reprocessing and quality inspection costs. Methods of finding the optimal tolerance limits are presented, and a numerical example is given. Sensitivity analyses are also performed to study the effect of a process standard deviation on this model.

• Culinary science and hospitality research
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• v.13 no.3
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• pp.127-136
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• 2007

The purpose of this study was to elucidate the relationship of service quality, product quality, price and customer satisfaction. Data were collected from 214 customers at the university foodservice and analyzed with SPSS 14.0. The verified results in these research hypotheses are as follows. First, the relationship between the service quality and customer satisfaction shows that tangibles(t=2.444) and responsiveness(t=2.431) have significantly positive influence upon customer satisfaction. Second, it was indicated that product quality(t=12.711) also has significantly positive influence upon customer satisfaction. Third, price (t=0.051) has no positive effect on customer satisfaction. Managerial contributions, limitation, and future research directions are discussed at the end of the paper.

• Journal of Korean Society for Quality Management
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• v.35 no.3
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• pp.55-65
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• 2007

The purpose of this study is to analyze the causal relationship among categories in the Korean National Quality Award(KNQA) model. The survey instrument consists of 79 questions from seven categories in the KNQA. Structural Equation Modeling(SEM) is used to analyze the empirical data and estimates the path coefficients among the KNQA categories. The result of this research indicates that Leadership drives systems that create Results through Foundation and Direction. Among eighteen hypotheses, sixteen hypotheses are statistically significant. Especially, this research indicates that Foundation and Direction are important mediating factors.

• Knowledge Management Research
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• v.15 no.2
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• pp.67-88
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• 2014

This study aims to investigate on measuring the success of e-Learning. For this purpose, we proposed a research model that consists of e-Learning contents quality, e-Learning system quality, e-Lecturing quality, sense of e-Learning community factors as independent factors and e-Learning and e-Learning satisfaction as mediators and tested it empirically based on the structural equation model. The empirical results showed that e-Learning contents quality, e-Learning system quality, sense of e-Learning community factors directly lead to e-Learning. The study also found that e-Learning contents quality, e-Lecturing quality, sense of e-Learning community factors bring about higher e-Learning satisfaction and that e-Learning satisfaction has a positive impact on e-Learning. Furthermore, the research discovered that both e-Learning and e-Learning satisfaction have a significant relationship with e-Learning net benefits. This research renders its theoretical contribution to analyzing a positive influence of sense of e-Learning community, a newly suggested variable added to the existing IS success model in this study, on e-Learning. From a practical view, the findings of this study can lead to improving the quality of e-Learning in today's era where the growth of e-Learning industry is quite noticeable.

• Proceedings of the KIEE Conference
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• 2001.07b
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• pp.1070-1072
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• 2001

In recent years, customers and power supplies are interested in power quality. Demands of customers are change from standard quality of distribution power system to various high quality of distribution power system. so, it is necessary to apply power quality compensator, in our project, we develop the power quality compensator of 150kVA which compensates power factor and voltage sag, interruption. it is very frequently occurred power qualify problems[1,2]. As a series and shunt compensator, power quality compensator consists of two inverters with common do link capacitor bank. It compensates the current quality in the shunt part and the voltage qualify in the series part. In this paper we present the design and control algorithm of power quality compensator. As a control algorithm is implemented by digital controller, we consider sample-and-hold of signals. In this simulation, we use EMTDC/PSCAD V3.0 software which can simulate instantaneous voltage and current.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.66-71
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• 2008

A total of 284 milled rice (MR) marketed in Korea were analyzed for grading characteristics (head rice, broken kernels, chalky kernels, and damaged kernels%), color characteristics (L-, a-, b-values, and whiteness), protein content (%), and the cooked rice (CR) sensory quality to investigate the key characteristics affecting the overall sensory quality of rice marketed in Korea. Relatively high correlation with the overall sensory quality of the CR was found in color characteristics such b-value of the CR (r=-0.779) and MR (r=-0.545), the a-value of the CR (r=0.513), and the whiteness (r=0.298) of the MR, compared to protein (r=-0.150), and the moisture (r=0.158) contents of the MR and the percentage of head rice (r=0.195). Partial least squares (PLS) regression of the CR b-value with various characteristics of the MR showed that CR b-value was increased with MR b-value effectively, followed by protein content, damaged kernels, chalky kernels, and colored kernels of MR while it was decreased with whiteness and moisture content for the MR.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.5
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• pp.576-588
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• 2017

Some of the mariculture grounds near Ongjin-gun, Korea, were designated as mariculture management areas in 2007. Areas are so designated when the environmental quality of the mariculture ground deteriorates or there is an outbreak of hypoxia or harmful red tide that kills mariculture organisms. We surveyed the water and sediment quality and examined the mortality of mariculture organisms in the Ongjin-gun mariculture area. In a survey conducted in 2016, the water quality was better than the environmental quality standards for mariculture grounds, excepts for dissolved inorganic nitrogen, and the sediment quality was good. However, there was still mortality of mariculture organisms in some of the designated management areas. The areas that met the environmental quality standards should be delisted and the areas in which we observed mortality should be classified as management areas. This will enable the sustainable development of aquaculture and preserve healthy mariculture grounds.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup3
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• pp.107-111
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• 2016

This study aimed to determine sleep disorders and associated risk factors in leukemia patients undergoing chemotherapy in Imam Khomeini Hospital of Sari, Iran. This cross-sectional study was conducted in 2015 with 100 patients selected. Inclusion criteria included complete mental and psychological health and being over 18 years old, and exclusion criteria included suffering other cancers, other chronic diseases, concurrent radiotherapy, and chemotherapy. The Pittsburgh Sleep Quality standard questionnaire was used to collect data. The questionnaire consisted of mental sleep quality, sleep latency, sleep duration, sleep quality, sleep disturbances, use of sleeping drugs, and impaired daily functioning. Data were analyzed by software SPSS 18 and by using descriptive and inferential tests (Pearson, Spearman, T-test and chi-square). Totals of 47 men (47%) and 53 women (53%) with a mean age of $44.1{\pm}1.7$, participated in the study. The mean overall score of sleep quality was $9.3{\pm}3.9$, which represents the average sleep quality in most participants. T-test shows that males have better sleep quality than females (t=2.1; 95%CI:0.004-0.25; P<0.01). Also the sleep quality increased with age (r=0.22, P=0.03). Results show that the amount of sleep quality was only moderate in most patients, so it is necessary to take coping strategies to improve their quality of sleep.

• Journal of Environmental Impact Assessment
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• v.22 no.3
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• pp.203-217
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• 2013

This study looked at how to establish effluent limitation standards for formaldehyde, a toxic chemical widely used in industries. To this end, we reviewed Water Quality Based Effluent Limitation (WQBEL), Technology Based Effluent Limitation (TBEL), and water quality criteria for protection of human health and aquatic organism. Based on the results, we estimated formaldehyde effluent limitation standards appropriate to control water quality of industrial wastewater in Korea. However, this study has limits due to the lack of some data necessary in estimating formaldehyde effluent limitation. For example, although water quality criteria based on non-carcinogenic properties of formaldehyde were calculated, those based on carcinogenic properties were not be able to estimate because of the absence of applicable cancer potency factor q1. Without applicable factor, we calculated water quality standards for formaldehyde based on water quality criteria of advanced countries including the United States, while with no water quality standard we referred to applicable drinking water quality standards of other countries. For eco-toxicity based on water quality criteria, proper figures could not be calculated since there have been few reliable data.