• Title/Summary/Keyword: adjustment process

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Development of Integrated Variable Sampling Interval EngineeringProcess Control & Statistical Process Control System (가변 샘플링간격 EPC/SPC 결합시스템의 개발)

  • Lee, Sung-Jae;Seo, Sun-Keun
    • Journal of Korean Institute of Industrial Engineers
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    • v.32 no.3
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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.

Procedure for monitoring special causes and readjustment in ARMA(1,1) noise model (자기회귀이동평균(1,1) 잡음모형에서 이상원인 탐지 및 재수정 절차)

  • Lee, Jae-Heon;Kim, Mi-Jung
    • Journal of the Korean Data and Information Science Society
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    • v.21 no.5
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    • pp.841-852
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    • 2010
  • An integrated process control (IPC) procedure is a scheme which simultaneously applies the engineering control procedure (EPC) and statistical control procedure (SPC) techniques to reduce the variation of a process. In the IPC procedure, the observed deviations are monitored during the process where adjustments are repeatedly done by its controller. Because the effects of the noise, the special cause, and the adjustment are mixed, the use and properties of the SPC procedure for the out-of-control process are complicated. This paper considers efficiency of EWMA charts for detecting special causes in an ARMA(1,1) noise model with a minimum mean squared error adjustment policy. And we propose the readjustment procedure after having a true signal. This procedure can be considered when the elimination of the special cause is not practically possible.

Mediation Effect of Empowerment and Social Support in the Relationship between Parent-child Relationship and College Adjustment (부모-자녀 관계와 대학 적응 간의 관계에서 임파워먼트와 사회적 지지의 매개효과)

  • Shin, Sun-Hwa
    • The Journal of the Korea Contents Association
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    • v.19 no.10
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    • pp.421-431
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    • 2019
  • This study aimed to verify the mediating effects of empowerment and social support in the process of parent-child relationship affecting the college adjustment. In this descriptive research, 219 university students were recruited as participants. Data collection was carried out from May to June 2019 via online survey. The results showed that parent-child relationship had significant direct effects on empowerment, social support, and college adjustment. Moreover, parent-child relationship had significant indirect effects on students' college adjustment via empowerment and social support. The indirect effect of empowerment was significantly higher than the indirect effect of social support with respect to the influence of parent-child relationship on college adjustment. It is necessary to improve parent-child relations and emotional intimacy through social support to promote the college adjustment of students. In addition, it is important to apply a program that can enhance empowerment, which is a powerful factor in college adjustment.

Improvement of Water Treatment Efficiency by pH Decreasing Agent (H2SO4) for Droughty Seasons (갈수기 정수장운영관리 사례 - 갈수기 pH저감제(황산)투입에 의한 정수처리효율 향상)

  • Ka, Gilhyun;Kim, Yunyung;Lee, Junho;Ahn, Chihwa;Han, Ihnsup;Min, Byungdae
    • Journal of Korean Society on Water Environment
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    • v.24 no.4
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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 $8{\mu}g/L$.

A Study on Correction Approach for the Life Safety Index for Personalized Services Based on User Profiles (생활안전 예방서비스 사용자 프로파일 기반 맞춤형 서비스를 위한 생활안전지수 보정 방안 연구)

  • Hyesu Oh;JongWoon Jeong;Jaeil Lee
    • Journal of Korean Society of Disaster and Security
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    • v.16 no.3
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    • pp.35-43
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    • 2023
  • This study introduces a study on the adjustment methods of the Life Safety Index. The Life Safety Index is a service provided by the Life Safety Prevention Service System. It comprehensively evaluates individuals' levels of safety in their daily lives, continually monitors their safety status, and presents a comprehensive index to prevent safety accidents in advance. Previous studies have developed the Life Safety Index using evaluation criteria (items) for assessing life safety prevention services, incorporating both the AHP (Analytic Hierarchy Process) and Likert Scale techniques. In this study, we build upon this existing Life Safety Index and explore methods for applying adjustment factors based on individuals' characteristics to enhance its accuracy and customization. We develop adjustment factors using existing national statistics to provide personalized services tailored to individual profiles. Therefore, this paper proposes a method for providing customized services by applying adjustment factors to the Life Safety Index, contributing to the development and application of life safety index adjustment methodologies.

The Roles of Rural Extension for the Structural Adjustment of Rural Korea (농촌구조개선을 위한 농촌지도사업의 역할)

  • Im, Sang-Bong
    • Journal of Agricultural Extension & Community Development
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    • v.2 no.1
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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.

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Improvement Scheme of Airborne LiDAR Strip Adjustment

  • Lee, Dae Geon;Lee, Dong-Cheon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.36 no.5
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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.

A Study of Place Attachment to Home, Acculturative Stress, and Psychological Adjustment Among Korean Youth in the United States (재미 한인청소년의 집에 대한 장소애착, 문화적응 스트레스와 심리적 적응에 대한 연구)

  • Lee, Jin-Suk;Qin, Desiree B.
    • Korean Journal of Child Studies
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    • v.32 no.6
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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.

The Development of the Composite Index as a method of rate adjustment (의료보험수가 조정을 위한 복합지표 개발에 관한 연구)

  • 김한중;조우현;이해종
    • Health Policy and Management
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    • v.3 no.1
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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.

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Design of the GLR Chart in Integrated Process Control (통합공정관리에서 일반화가능도비 관리도의 설계)

  • Chun, Ga-Young;Lee, Jae-Heon
    • Communications for Statistical Applications and Methods
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    • v.17 no.3
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    • pp.357-365
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    • 2010
  • This paper considers the integrated process control procedure for detecting special causes in an IMA(1,1) noise process that is being adjusted using a minimum mean squared error adjustment. As a SPC procedure, we use a GLR chart for detecting special causes whose effects are the sustained shift or the sustained drift in the process mean, and the sustained shift in the process variance. For the design of the GLR chart, we derive expressions for the control limit which accurately satisfies the given in-control ARL.