• 한국공작기계학회논문집
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• 제14권5호
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• pp.21-26
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• 2005

It is important to measure the rotational accuracy of NC lathe spindle as it affects to the qualities of all machines machined by the NC lathe using in industries. The bad rotational accuracy of NC lathe spindle are caused mainly by wearness of the spindle in using and quality of spindle when machining and using low level bearings. It occurs especially in case of NC lathes because the cutting force acting to work-piece act on one side to the spindle not to both sides symmetrically. Therefore in this study, constructing experimental appratus for measuring of rotational accuracy by using eddy current type gap sensors, converters, screw terminal, data acquisition board inserted in computer and software f3r data acquisition, DT VEE ver. 5.0 and then error data acquired in the rotational accuracy test of NC lathe spindle are analysed in plots and statistical treatments.

• 한국공작기계학회논문집
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• 제16권6호
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• pp.43-48
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• 2007

It is important to measure the rotational accuracy of lathe spindle as it affects to the qualities of all machines machined by the lathe using in industries. The bad rotational accuracy of lathe spindle are caused mainly by wearness of the spindle in using and quality of spindle when machining and using low level bearings. It occurs especially in case of lathes because the cutting force acting to work-piece act on one side to the spindle not to both sides symmetrically. Therefore in this study, constructing experimental apparatus for measuring of rotational accuracy by using eddy current type gap sensors AEC5706PS and sensors, s-06LN, data acquisition board DT9834(USB type) and software for data acquisition, DT Measure Foundry ver. 4.0.7 etc., error data acquired in the rotational accuracy test of lathe spindle are analysed in plots and statistical treatments.

• 한국환경과학회지
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• 제27권10호
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• pp.883-899
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• 2018

In this study, water quality data of eight main sites in the Geumho River watershed were collected and analyzed for long-term changes in water quality over the period from 2005 to 2015. The results showed that BOD concentration was gradually improved by the Total Maximum Daily Load (TMDL), stages 1 and 2. Recently, a tendency of increasing BOD concentration was observed in the downstream section of the river. The concentration of COD was analyzed to be contaminated throughout the water system regardless of the water quality improvement project, and the TN concentration tended to increase in the midstream of the river from 2013. The TP concentration has clearly decreased from 2012 after the second stage of TMDL. For the statistical analysis of PCA ordination, monthly water qualities (pH, DO, Electrical Conductivity (EC), Water Temperature (WT), BOD, COD, TN, TP, TOC, and SS) and flow rate data for 5 years from 2012 to 2016 were used. Seasonally the Geumho River showed an increase in the TN concentration at point sources during the dry season (December to February). TP showed the effect of non-point sources in the summer, because rainfall has caused a rise in flow rate in the upstream. Besides, the origin of pollution source was changed from non-point sources with BOD, COD, and TOC.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2002년도 춘계공동학술대회
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• pp.225-231
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• 2002

POSCO $\#2$ Stainless steel making plant produces more than 600 thousand ton per year with a variety of products consisting of austenite and ferrite stainless steel to meet custrmers' needs since 1996. The plant has four different major processes, that are, EAF-AOD-VOD-CC to finally produce semi-product called as slab. In this study, we importantly took AOD process into consideration due to its roles such as to check and verify the final qualities through sampling inspection. But the lead-time from sampling to its verification takes five to ten minutes causing produrtivity loss as muck as the lead-time as a result. Of all indices for quality and process control the plant has, carbon ingredient in liquid type of steel is the most important since it affects in a great way to the characteristics of steel, if any problem. customers not satisfied with quality could issue a claim; therefore there is no way hut to guarantee it before delivery. in this study, to reasonably reduce lead-time ran save a cycle time and finally improve our productivity from a state-or-art alternative just such as applying statistical model based on multi-regression analysis into the A.O.D line by analyzing the statistical and technical relationship between carbon and the relevant some vital independent variables. In consequence, the model with R-square $87\%$ allowed the plant to predict, abbreviating the process in relations to sampling to verification. approximately the value of [C] so that operators could run the process line with reliability on data automatically calculated instead of actual inspection. In the future, we are going to do the best to share this type of methodology with other processes, if possible, to apply into them.

• 한국학교보건학회지
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• 제20권1호
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• pp.25-35
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• 2007

Purpose: This study was to identify the types and characteristics of health problems of middle school students in Gangwondo. Methods: The subjects of the study were 11 middle schools from 47 schools with nurse teachers in Gangwondo. The anecdotal records of the school health clinics were collected from March to December in 1998 with the agreement of nurse teachers of the schools. Results: 71.0% of the middle students visited the school health care clinics once or more than once. The mean frequency of health problems was 2.03 times per one year. The rate of health problems did not show any statistical differences by sex, school location, age, the day of the week and weather. However, there were statistical differences of the rate by month. The highest rate was showed in September, followed by June and April (F=2.52, p=0.01). Health problems were classified into 11 types. Gastrointestinal illness showed the largest proportion (60.6%). The oral illness showed statistical differences among the location of school, between municipal and rural area (t=-2.97, p=0.016). There were 411 types of signs and symptoms recorded. Among them, headache was showed the highest proportion with 2,122 cases (11.2%). Conclusion : The incidence rate of health problems was higher than that of earlier studies. It showed that the incidence rates and the types of diseasps in middle school students were different by school locations, characteristics of students, and months. To improve the qualities of primary cares in school health services, the reformed and unified anecdotal record system and the standardized guidelines for primary care are necessary.

• 한국습지학회지
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• 제14권1호
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• pp.11-20
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• 2012

본 연구의 목적은 더 나은 빗물관리를 위해 건물지붕에서 흘러내리는 빗물의 성상을 분석하고, 그 자료를 축적하는데 있다. 이에 빗물 유출수 성상을 분석한 결과(pH, COD, TSS, T-N, T-P, $NH_4$-N, $NO_3$-N, 장내세균, 일반미생물, 납, 카드뮴, 구리)지붕 유출수에서 흘러나오는 빗물의 성상이 직접 받은 빗물에 비해 약 2 ~ 3배 가량 더 오염되었고 (미생물 지수의 경우는 100배 이상) 초기 10분 동안 내린 오염물질량이 30분 모니터링한 빗물 오염물질량의 60% 이상 차지하고 있음을 알 수 있었다. 또한, 통계 요인분석을 통해 빗물 유출수 분석 항목들을 상대적으로 가까운 지표(변수)들로 구분 지을 수 있었다. 본 연구진은 이러한 지속적인 건물지붕빗물의 모니터링이 국내의 안전하고 경제적인 빗물 저장시설을 설치하는데 도움을 줄 거라 예상한다.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2006년도 추계 종합학술대회 논문집
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• pp.141-144
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• 2006

본 연구는 2006년 현재 대전광역시에 소재의 수영장의 성인여성회원 총 300명을 대상으로 298부의 설문지를 회수하여 사용하였다. 조사도구로 정신건강 대한 설문문항은 박지나(200l), 조석주(2000)의 연구를 기초로 요인 분석을 실시한 후 신뢰도 및 타당도를 검증, 사용하였다. 수집된 자료는 일원변량분석의 통계기법을 사용하였다. 이와 같은 연구방법 및 절차를 통하여 본 연구에서는 다음과 같은 결과를 도출하였다. 첫째, 성인 여성의 수영참가 빈도는 정신건강에 영향을 미친다. 둘째, 성인 여성의 수영참가 기간은 정신건강에 영향을 미친다. 셋째, 성인 여성의 수영참가 강도는 정신건강에 영향을 미친다. 이상의 결론을 종합하면 성인 여성이 수영에 참가함으로서 정신건강에 차이가 있는 것으로 나타났으며 성인 여성의 수영 참가를 높여 정신건강에 긍정적인 영향을 향상시키는데 기여한다고 할 수 있다.

• 상하수도학회지
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• 제29권4호
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• pp.469-479
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• 2015

This study have been conducted to analyze the feasibility of establishing Contamination Warning System(CWS) that is capable of monitoring early natural or intentional water quality accidents, and providing active and quick responses for domestic C_water supply system. In order to evaluate the water quality data set, pH, turbidity and free residual chlorine concentration data were collected and each statistical value(mean, variation, range) was calculated, then the seasonal variability of those were analyzed using the independent t-test. From the results of analyzing the distribution of outliers in the measurement data using a high-pass filter, it could be confirmed that a lot of lower outliers appeared due to data missing. In addition, linear filter model based on autoregressive model(AR(1) and AR(2)) was applied for the state estimation of each water quality data set. From the results of analyzing the variability of the autocorrelation coefficient structure according to the change of window size(6hours~48hours), at least the window size longer than 12hours should be necessary for estimating the state of water quality data satisfactorily.

• 한국조리학회지
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• 제16권3호
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• pp.188-204
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• 2010

본 연구에서는 국내 외식업체의 와인구매담당자, 즉 소믈리에, 매니저 등을 대상으로 고객장기 지향성에 긍정적으로 영향을 미치는 관계마케팅 요인을 파악함과 동시에 장기지향성이 형성되는 과정에서 관계의 질인 신뢰와 몰입의 역할을 규명함으로써 내수 경기침체와 치열한 경쟁으로 인해 어려움을 겪고 있는 와인공급업체의 영업활성화를 위한 마케팅 전략 수립에 도움을 주고자 함이다. 설문조사는 2010년 1월 15일부터 2월 13일까지 30일간 실시하였으며, 서울 시내 파인다이닝 레스토랑, 캐주얼 다이닝 레스토랑, 와인바 등의 와인구매담당자를 대상으로 하였다. 자료의 처리는 SPSS 15.0과 AMOS 7.0 통계패키지를 사용하여 빈도분석, 신뢰도 분석, 확인요인분석, 경로분석을 사용하였다. 그 결과, 관계마케팅 요인 중에서 커뮤니케이션과 판매자 전문성 요인은 신뢰와 정서적 몰입을 통하여 장기지향성에 긍정적인 영향을 미치는 것으로 나타났다.

• 한국식생활문화학회지
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• 제22권1호
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• pp.22-31
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• 2007

The purpose of this study was to analyze evaluation variables of service quality of Korean restaurant especially focused on cold noodle restaurants(CNR). The data were analyzed about customer’s expectation of food service quality, service quality was improved by employee’s service in restaurant and employee education in the focus on CNR. The survey was carried out 423 customers and 50 employees in Seoul and Kyunggi province. All statistical data analyses were conducted using the Statistical Package for the Social Science(SPSS version 10.0). The consumer’s evaluation score of service quality were significantly different by consumer’s characteristics. The well planned service at CNR must be developed according to consumer variables such as sex and age group. The evaluation score of service quality were not significantly different by seasonal variation and consumer’s menu selection. The evaluation score of service qualities in CNR were significantly different between customer variables with employees variables. All of the evaluation points of service quality in employees were significantly higher than customers. This result was show that well-trained employees were important factors in consumer satisfaction. Through the employee education program, consumer oriented service mind mort be to developed in employees and employees’ recognition about the importance of service increased the satisfaction of customer using CNR.