• 대한산업공학회지
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• 제32권3호
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• pp.210-218
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• 2006

Traditional statistical process control (SPC) applied to discrete part industry in the form of control charts can look for and eliminate assignable causes by process monitoring. On the other hand, engineering process control (EPC) applied to the process industry in the form of feedback control can maintain the process output on the target by continual adjustment of input variable. This study presents controlling and monitoring rules adopted by variable sampling interval (VSI) to change sampling intervals in a predetermined fashion on the predicted process levels under integrated EPC and SPC systems. Twelve rules classified by EPC schemes(MMSE, constrained PI, bounded or deadband adjustment policy) and type of sampling interval combined with EWMA chart of SPC are proposed under IMA (1,1) disturbance model and zero-order (responsive) dynamic system. Properties of twelve control rules under three patterns of process change (sudden shift, drift and random shift) are evaluated and discussed through simulation and control rules for integrated VSI EPC and SPC systems are recommended.

• Journal of the Korean Data and Information Science Society
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• 제21권5호
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• pp.841-852
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• 2010

통합공정관리는 공정의 변동을 줄이기 위하여 공학적 공정관리와 통계적 공정관리를 병행하는 절차이다. 통합공정관리의 기본적인 절차는 잡음과 이상원인이 공존하는 공정에 대하여 매시점마다 수정절차를 통하여 공정편차를 백색잡음으로 전환하며, 수정된 공정을 관리도를 이용하여 이상원인의 발생 여부를 탐지하게 된다. 이때 공정은 이상원인 발생 전에는 백색잡음이 되지만, 이상원인 발생 후에는 이상원인과 수정절차의 효과가 혼합되어 다양한 형태의 시계열 모형으로 변환하게 된다. 이 논문에서는 잡음모형으로 자기회귀이동평균(1,1) 모형을 가정하고 통합공정관리 절차를 수행하는 경우, 지수가중이동평균 관리도를 사용하여 이상원인을 탐지하는 절차에 대한 효율을 살펴보았다. 또한 이상원인의 신호 후 이를 제거하기 힘든 경우 사용할 수 있는 재수정 절차를 제안하였다.

• 한국콘텐츠학회논문지
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• 제19권10호
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• pp.421-431
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• 2019

본 연구는 부모-자녀 관계가 대학 적응에 영향을 미치는 과정에서 임파워먼트와 사회적 지지의 매개효과를 검증하기 위해 수행하였다. 본 연구는 서술적 조사연구로, 일개 대학에 재학 중인 219명의 대학생을 대상으로 하였고, 2019년 5월부터 6월까지 온라인 설문조사를 통해 자료를 수집하였다. 연구결과, 부모-자녀 관계는 임파워먼트, 사회적 지지 및 대학 적응에 유의한 직접효과가 있었다. 그리고 부모-자녀 관계는 임파워먼트와 사회적 지지를 통해 대학 적응에 미치는 영향에서 유의한 간접효과(매개효과)가 있었다. 부모-자녀 관계가 임파워먼트를 통해 대학 적응에 영향을 미치는 간접효과는 사회적 지지를 통한 간접효과보다 유의하게 높게 나타났다. 이러한 결과를 토대로 대학생의 대학 적응을 증진시키기 위한 방안으로 부모-자녀 관계 개선, 사회적 지지를 통한 정서적 친밀감 향상, 대학 적응에 강력한 요인인 임파워먼트 강화가 필요함을 논의하였다.

• 한국물환경학회지
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• 제24권4호
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• pp.415-422
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• 2008

Drinking water treatment is enhanced by coagulant dosages and chlorine injection because of pH increase in raw water in droughty seasons such as spring and fall. But water quality deterioration is occurred by increase in residual aluminium and disinfection by-products. Coagulation process can be used to control natural organic matter (NOM) during water treatment. The effect of coagulation process appeared to depend on the pH of water rather than coagulant dosages. In this study, for water treatment in high pH season $H_2SO_4$ was applied for pH adjustment at full scale. Before and after pH adjustment by $H_2SO_4$ injection, water quality of drinking water was evaluate. In the result of investigation of total organic carbon (TOC) removal in high pH season, TOC was removed approximately 30~40%, which showed decrease in water treatment efficiency. Also, it is increased both particle numbers and residual Al concentration in the water. After $H_2SO_4$ injection for adjustment to pH<7.5 in settled water, treated water turbidity decreased in 0.047 NTU from 0.059 NTU, and particle numbers of filtered water decreased in 20/mL from 90/mL. On the other side, TOC removal efficiency increased in approximately 10% after adjustment of pH. In the result of decrease in pH in raw water through more coagulants and prechlorine without $H_2SO_4$ injection, trihalomethanes (THMs) concentration increased in $16{\mu}g/L$ from $8{\mu}g/L$.

• 한국방재안전학회논문집
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• 제16권3호
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• pp.35-43
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• 2023

본 논문은 생활안전지수 보정 방안에 대한 연구를 소개한다. 생활안전지수는 생활안전 예방서비스 시스템에서 제공되는 서비스로써, 개인의 일상생활 안전수준을 종합적으로 평가하여 개개인의 안전상태를 수시로 파악하고, 안전사고를 사전에 예방하기 위해 종합지수 형태로 나타낸다. 이전의 선행 연구에서는 생활안전 예방서비스를 평가하기 위한 평가 기준(항목)을 기반으로 하여 AHP(Analysis Hierarchy Process)와 Likert Scale 기법을 혼용하여 개발되었다. 이에 본 연구에서는 이러한 기존의 생활안전지수를 기반으로, 개인의 특성에 따른 보정 인자를 생활안전지수에 적용하는 방안을 탐구하고자 한다. 기존의 국가 통계를 활용한 보정 인자를 개발하여 개인 프로파일에 맞는 개별화된 서비스를 제공하는 방법을 제시한다. 따라서 본 논문은 생활안전지수 개발 및 보정 방법론에 대한 응용을 통해 사용자 맞춤형 서비스를 제공하는 방법에 대하여 제안하고자 한다.

• 농촌지도와개발
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• 제2권1호
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• pp.71-79
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• 1995

The rural extension in Korea faces transient period since Green Revolution. The urban-centered rapid industrialization policies have initiated the changes in rural and agricultural sector. Nowadays, the World Trade Organization (WTO), newly established by the agreement of the Uruguay Round (UR), is accelerating the changes in rural areas. The rural structural adjustment program established in 1990, in order to cope with the internal and external changes encompassing rural Korea. The rural structure adjustment program is a political responses to reduce the development gaps among industries and regions within the country and to reinforce the price competitiveness of agricultural products toward trade liberalization. This study aims to apply the contents and principles of the rural structural adjustment program for the extension education. It argues that the rural extension should play a pivotal role to gather, process, and deliver the information related to the rural structural adjustment initiating rapid rural social changes. It suggests that the rural extension services should deal with the development of industries through introducing business management techniques and linking relevant laborers, and the education and employment guidance of potential employees as well as the technological assistance on farm management to farmers.

• 한국측량학회지
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• 제36권5호
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• pp.355-369
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• 2018

LiDAR (Light Detection And Ranging) strip adjustment is process to improve geo-referencing of the ALS (Airborne Laser Scanner) strips that leads to seamless LiDAR data. Multiple strips are required to collect data over the large areas, thus the strips are overlapped in order to ensure data continuity. The LSA (LiDAR Strip Adjustment) consists of identifying corresponding features and minimizing discrepancies in the overlapping strips. The corresponding features are utilized as control features to estimate transformation parameters. This paper applied SURF (Speeded Up Robust Feature) to identify corresponding features. To improve determination of the corresponding feature, false matching points were removed by applying three schemes: (1) minimizing distance of the SURF feature vectors, (2) selecting reliable matching feature with high cross-correlation, and (3) reflecting geometric characteristics of the matching pattern. In the strip adjustment procedure, corresponding points having large residuals were removed iteratively that could achieve improvement of accuracy of the LSA eventually. Only a few iterations were required to reach reasonably high accuracy. The experiments with simulated and real data show that the proposed method is practical and effective to airborne LSA. At least 80 % accuracy improvement was achieved in terms of RMSE (Root Mean Square Error) after applying the proposed schemes.

• 아동학회지
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• 제32권6호
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• pp.33-48
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• 2011

This study examined the relationships between place attachment to home, acculturative stress, and psychological adjustment among Korean youth in the United States. In particular, this study sought to better understand how place attachment to home and acculturation stress impacts upon youth's psychological adjustment, as measured by depression and self-esteem. The subjects consisted of 225 Korean youths (113 males and 111 females) residing in Michigan in the USA, of whom 47.6% attended middle school while 52.4% of whom attended high school. The instruments utilized were the acculturative stress scale (Sandhu and Asrabadi, 1994), the place attachment scale (Choi, Lee, & Han, 2009), Radloff's depression scale (CES-D), and Rosenberg's self-esteem scale. Hierarchical multiple regression analyses were used to assess the predictive effects of place attachment to home and acculturative stress on youth's psychological adjustment, alongside controlling demographic variables. The findings indicated that place attachment to home and acculturative stress impacted upon depression and self-esteem, as experienced by the youths examined. These results have implications for our understanding of the importance of both youths' place attachment to home and acculturative stress in the acculturation process.

• 보건행정학회지
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• 제3권1호
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• pp.84-101
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• 1993

The current method of rate adjustment is based on the evaluation of the financial performance of hospitals. The method has the disadvantages such as too complicated, expensive process as well as low reliability due to small sample size. This study, therefore, develops a new model for the rate adjustment with the use of the composite index. In addition to that, it examines the validity of the model by comparing the result of the new method with that of the conventional method. The idea of the new model comes from the Medicare Economic Index(MEI) on which physician fees for the Medicare patients are adjusted periodically in the United States. Medical costs are classified into three groups : labor costs, materials and other expenses. Labor costs are subdivided into physicians and other personnels. Materials are subdivided into drugs and others. Other expenses are subdivided into 5 items. Macro economic indices are selected for each cost item in order to reflect the cost inflation during the specific period. Then the composite index which integrate all items according to the ration of each item in the total costs is calculated. The result from the application of empirical data to the new model is very similar to that of the current method. Furthermore, this method is very simple and also to easy to get social concensus. This model can be replaced the current method based on the analysis of the financial performance for the adjustment of medical fees.

• Communications for Statistical Applications and Methods
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• 제17권3호
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• pp.357-365
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• 2010

통합공정관리란 잡음이 내재하는 공정에 대하여 수정조치를 취하고, 수정활동 중 공정에 이상원인이 발생하면 이를 관리도를 통해 탐지하여 제거하는 절차를 일컫는다. 이 논문에서는 공정의 잡음모형으로 IMA(1,1) 모형을 가정하고 최소평균제곱오차 수정절차를 수행할 때 일반화가능도비 관리도를 사용하여 이상원인을 탐지하는 절차를 고려하고 있으며, 이러한 상황에서 일반화가능도비 관리도의 관리한계를 설정하는 설계 방법을 제안하였다. 이상원인의 효과로는 공정 평균의 지속적 변화와 지속적 흐름 그리고 공정 분산의 지속적 변화를 고려하였다.