• Journal of Korean Society for Quality Management
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• v.47 no.3
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• pp.537-552
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• 2019

Purpose: The development of information technology makes it easy to utilize high-dimensional categorical data. In this regard, the purpose of this study is to propose a novel method to select the proper categorical variables in high-dimensional categorical data. Methods: The proposed feature selection method consists of three steps: (1) The first step defines the goodness-to-pick measure. In this paper, a categorical variable is relevant if it has relationships among other variables. According to the above definition of relevant variables, the goodness-to-pick measure calculates the normalized conditional entropy with other variables. (2) The second step finds the relevant feature subset from the original variables set. This step decides whether a variable is relevant or not. (3) The third step eliminates redundancy variables from the relevant feature subset. Results: Our experimental results showed that the proposed feature selection method generally yielded better classification performance than without feature selection in high-dimensional categorical data, especially as the number of irrelevant categorical variables increase. Besides, as the number of irrelevant categorical variables that have imbalanced categorical values is increasing, the difference in accuracy between the proposed method and the existing methods being compared increases. Conclusion: According to experimental results, we confirmed that the proposed method makes it possible to consistently produce high classification accuracy rates in high-dimensional categorical data. Therefore, the proposed method is promising to be used effectively in high-dimensional situation.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2005.05a
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• pp.473-476
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• 2005

Today's manufacturing industry is facing challenges from advanced difficult-to-machine materials (WC-Co alloys, ceramics, and composites), stringent design requirements (high precision, complex shapes, and high surface quality), and machining costs. Advanced materials play an increasingly important role in modem manufacturing industries, especially, in aircraft, automobile, tool, die and mold making industries. The greatly-improved thermal, chemical, and mechanical properties of the material (such as improved strength, heat resistance, wear resistance, and corrosion resistance), while having yielded enormous economic benefits to manufacturing industries through improved product performance and product design, are making traditional machining processes unable to machine them or unable to machine them economically. In this paper, mechanical characteristic evaluation test of fine powder type WC-Co alloy was accomplished to obtain clear data for miniaturized special die parts machining with high reliability and high quality.

• Journal of Korean Society on Water Environment
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• v.36 no.2
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• pp.125-136
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• 2020

In this study, we identified the major pollution-zones of the mainstream and its tributaries of Gongneung stream and investigated their pollution sources based on water quality, flowrate and pollution-load data of the stream having the characteristics of the urban-rural complex to examine the effect of the tributaries on the water quality changes in the mainstream. The water quality and flowrate data were collected for 10 months (2018 ~ 2019) at 3 points of mainstream and ten tributaries. Water quality index (WQI), load duration curve (LDC), discharge load density (DLD)and delivery ratios for each tributary were obtained so as to investigate the pollution characteristics and some of the information visualized on GIS. The main pollution-zone in the Gongneung stream was in the middle and lower streams, and the tributaries that may affect the pollution of the area were JS, JY, SL and SM. JS and SL had low WQI levels (34.7/37.5) and DLD (kg/d/㎢) of BOD and T-P were relatively high in JY (99.2/6.00) and SL (60.0/2.07). BOD and T-P delivery ratios in JS were high (0.94/0.83), suggesting that JS had significant influence on the water quality of the main pollution-zone in the Gongneung stream. Meanwhile, SM having a high T-P delivery ratio (0.97) was found to be more affected by the non-point source due to the higher LDC excess rate (%) in the low flow compared to high flow. This study provides basic data on the water quality and pollution characteristics of the Gongneung stream, and the analysis results are expected to be used as examples for identifying the main pollution-zone and tributaries of stream and their pollution sources.

• Proceedings of the KIEE Conference
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• 2006.07a
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• pp.125-126
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• 2006

Data storage and data communication currently pose a major problems for all parties involved with power quality and power system monitoring. The Problem aries from the tremendous amount of data involved. There is a common desire in the power industry to find new techniques for high-accuracy data compression and data storage. This paper introduces a data compression technique that is very suitable for application to power quality waveforms. The proposed technique is applied in splitting the monitored signal into two components. Those are stationary and nonstationary components. Each component is compressed and encoded.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.2
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• pp.179-189
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• 2005

Recently air quality modeling studies for industrial complex and large cities located in the coastal regions have been carried out. Especially, the representation of atmospheric flow fields within a model domain is very important, because an adequate air quality simulation requires an accurate portrayal of the realistic three -dimensional wind fields. Therefore this study investigated effect of using high resolution terrain height data in numerical simulation. So the experiments were designed according to the detail terrain height with 3second resolution or not. Case 30s was the experiment using the terrain height data of USGS and Case 3s was the other using the detail terrain height data of Ministry of Environment. The results of experimental were more remarkable. In Case 3s, temperature indicated similar tendency comparing to observational data predicting maximum temperature during the daytime and wind speed made weakly for difference of terrain height.

• Journal of Korean Society for Quality Management
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• v.32 no.3
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• pp.45-61
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• 2004

This study is to identify the differences in service quality for the 2nd-scale hospital Industries. The subjects of this survey for the empirical analysis are limited to the 2nd- scale hospitals in Korea: data are collected in Seoul, Incheon and Kyungki areas. The results are as follows. First, the efficiency for hospital operations confirmed the differences in bed scale. Second, the high-efficiency hospitals attach importance to efficiency with more than 100 bad scale and the low-efficiency hospitals attach Importance to service quality with less than 100 bed scale.

• Journal of Korean Library and Information Science Society
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• v.21
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• pp.401-429
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• 1994

According to database and information technology development, many interests of database quality control have being increase. The purpose of database quality control is improvement quality of data itself as well as database system to satisfy user's need. As this paper was especially written about quality control of bibliographic database, to embody complete bibliographic database, it was invested numerous errors and its case by analyzing MARC records. In addition, it was presented that high degree's cataloging education, introduction of su n.0, pporting systems, and development of intelligent quality control system for quality improvement.

• Journal of Distribution Science
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• v.16 no.12
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• pp.13-21
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• 2018

Purpose - Because it is not possible to assess the quality of service products before experiencing them, one feature of a service product is quality uncertainty; hence consumers may react sensitively to pricing. It is necessary to investigate how different pricing strategies affect consumer purchase intention depending on the level of service quality uncertainty. Research design, data, and methodology - The authors have investigated the potential impact of the level of service quality uncertainty, price discount rate and presentation method on consumer purchase intention. A play was selected as an experimental stimulus, and Vietnamese consumers were surveyed to verify the hypotheses. Results - When uncertainty regarding service quality is low, consumer purchase intention is higher when the price discount rate is high or when the price is low. When uncertainty regarding service quality is high, if the normal price, discount rate, and discounted price are presented simultaneously, consumer purchase intention is higher when the price discount rate is low, but when only the discounted price is presented, purchase intention is higher when the price discount rate is high. Conclusions - The results of this study can provide valuable practical implications for pricing for service products with quality uncertainty.

• The Korean Journal of Rehabilitation Nursing
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• v.13 no.2
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• pp.114-122
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• 2010

Purpose: The purpose of this study was to identify the health promotion, stress and the quality of life and relationship between those factors in patients with genital neoplasms. Method: Data of 151 subjects with genital neoplasms were collected from August 15 to October 12, 2009 at out-patient clinic in one general hospital in Daegu. Results: The mean score of health promotion of the subjects was 1.49 (${\pm}0.53$), stress of gynecologic cancer was 1.36 (${\pm}0.76$) and the quality of life of the subjects was 2.38 (${\pm}0.59$). There was a negative correlation between the quality of life and stress (r=-.482, p<.001), and positive correlation between the quality of life and health promotion (r=.442, p<.001) in the subjects. Conclusion: This study showed correlations between the health promotion, stress and the quality of life of patients with genital neoplasms. The quality of life of the patients with genital neoplasms was low when their stress was high. In contrast, their quality of life was high when the score of health promotion was high. Considering the research findings, it is necessary to develop a health promotion program for patients with genital neoplasms to strengthen their health promotion behaviors.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.3
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• pp.18-26
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• 2017

Defense industries which require high reliability need an optimized quality management system with well-planned implementation. And the government should examine the overall status of defense industries, then establish practical policies with a proper support plan in required areas to upgrade the quality management level of manufacturers. Thus, DTaQ developed the model for 2 years from 2014, which specialized in quality management level analysis for defense industries. And a survey has been undertaken with that model by DTaQ and Korea Research Center in 2016. The surveyed companies randomly sampled among those which have more than 30 employees and delivery history over past 3 years, and finally 106 defense industries were selected. This paper present survey method and indexes for survey of defense industry quality management level. The survey was conducted in the order of planning, data collection and data processing, and the validity and reliability of the data were verified to increase objectivity of survey results. The survey contents mainly consist of system quality and management quality. System quality includes Product Development Management, Production Operation Management, supply chain quality management, Safety & Environment Management and Reliability Management, on the other hand, management quality includes Strategic Leadership, Human Resource Management, Customer Market Management and Information & Knowledge Management. Thus this proposes the current overall quality management status of the 106 defense industries and shows level differences by company sizes and manufacturing sectors based on the result of survey. Specifically, this paper enables to track the areas which need prompt government support with the policy directions to make quality management level higher. Therefore, it is expected that this can be used as reference data in establishing quality policies for military supplies in the future.