• Communications for Statistical Applications and Methods
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• v.24 no.1
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• pp.1-13
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• 2017

This manuscript summarized advances in bootstrap methods for long-range dependent time series data. The stationary linear long-memory process is briefly described, which is a target process for bootstrap methodologies on time-domain and frequency-domain in this review. We illustrate time-domain bootstrap under long-range dependence, moving or non-overlapping block bootstraps, and the autoregressive-sieve bootstrap. In particular, block bootstrap methodologies need an adjustment factor for the distribution estimation of the sample mean in contrast to applications to weak dependent time processes. However, the autoregressive-sieve bootstrap does not need any other modification for application to long-memory. The frequency domain bootstrap for Whittle estimation is provided using parametric spectral density estimates because there is no current nonparametric spectral density estimation method using a kernel function for the linear long-range dependent time process.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.5
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• pp.560-568
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• 2004

We performed the numerical study on the characteristics of the 3-D airflow and dynamic cross contamination in the photolithography process cleanroom. The nonunifurmity, the deflection angle and the global cross contamination were used for analyzing the characteristics and performances of cleanroom. From the numerical results, we knew that the airflow characteristics of the cleanrooms are largely affected by the porosity of panel and the adjustment of dampers and the global cross contamination varies with the location of source and the passage of time through the concentration ratio.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.151-156
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• 2003

We performed the numerical study on the characteristics of the airflow and cross contamination in the photolithography process cleanroom. The nonuniformity, the deflection angle and the global cross contamination were used for analyzing the characteristics and performances of cleanroom. We knew that the airflow characteristics of the cleanrooms are largely affected by the porosity of panel and the adjustment of dampers. And the numerical result showed that the global cross contamination varies with the location of source and the passage of time.

• The Korean Journal of Applied Statistics
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• v.25 no.4
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• pp.589-603
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• 2012

Mahalanobis-Taguchi system(MTS) is a statistical tool for classifying the normal group and abnormal group in multivariate data structures. In addition to the classification itself, the MTS uses a method for selecting variables useful for the classification. This method can be used efficiently especially when the abnormal group data are scattered without a specific directionality. When the feedback adjustment procedure through the measurements of the process output for controlling process input variables is not practically possible, the reset procedure can be an alternative one. This article proposes a reset procedure using the MTS. Moreover, a method for identifying input variables to reset is also proposed by the use of the contribution. The identification of the root-cause parameters using the existing dimension-reduced contribution tends to be difficult due to the variety of correlation relationships of multivariate data structures. However, it became possible to provide an improved decision when used together with the location-centered contribution and the individual-parameter contribution.

• Journal of Families and Better Life
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• v.14 no.3
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• pp.237-248
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• 1996

This study regarded the marital problem solving as the process of ego states marital problem perception and marital problem solving behaviors and was to verify that the match of husband and wife in that process differed in marital adjustment, The subjects of the study were 225 married couples for 1-10 years. The results of the study were summarized as following: 1) Husband/wife's marital adjustments differed in a accordance with marital problem solving behavior matches between husband and wife. 2) Marital problems solving behaviors were the most effected by marital problem perception and were indirectly effected by ego states. Particularly marital problem solving behaviors was the more effec ted by perception of husband than of wife.

• Journal of the Korean housing association
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• v.9 no.2
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• pp.51-56
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• 1998

With the improved quality of life standards interior design is recently gaining more concerns than ever before. This requires more well organized and standardized business and marketing in the field. Consequently, a few interior design firms concern about computerizing their marketing process to do this. This paper focuses on developing a computerized consulting system assisting interior design. For this a standardized consulting process is developed. The process includes the input of customer's information, surveying customer's preferences on interior design styles, estimation and budget adjustment, suggesting packages and interior items, and printing consulting results. The system developed is valuable in three different viewpoints: First, from the customer's view it can be a decision-making tool. Second, from the consultant's point of view it is a front-end marking tool. Third, it is an information collector from the viewpoint of an interior design firm.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.7
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• pp.1158-1168
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• 1994

A variable structure control scheme(VSCS) with sliding mode that can be applied to the process with input/output(I/O) delay is proposed and its control performances is evaluated. The proposed VSCS with and output feedback scheme comprises a variable structure controller, a servo dynamic for tracking the set-poing, and a Smith predictor for compensating the effects of time delay. The robustness against the parameter variations and external disturbances can be achieved by the proposed VSCS even when the controlled process includes I/O delay. And the desired transient response is obtained by simple adjustment of the coefficients of the switching surface equation.

• Journal of Institute of Control, Robotics and Systems
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• v.3 no.2
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• pp.204-213
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• 1997

In this paper, an application of fuzzy-neuron reasoning to the control of an activated sludge plant is presented. The activated sludge process is widely used in modern wastewater treatment plants. The operation control of the activated sludge process, however, is difficult due to the following reasons : 1)The complexity of the wastewater components, 2)the change of the wastewater influent, and 3)the adjustment errors in the control process. Because of these reasons, it is difficult to obtain mathematical model that really reflect the relationship between the variables and parameters in the process of wastewater treatment correctively and effectively. In this paper, the activated sludge process(A.S.P.) is modeled by a new fuzzy-neuron network representing nonlinear characteristics. These fuzzy-neurons have fuzzy rules with complementary membership function. Based on the constructed model, graphic simulator on X-window system as a graphic integrated environment is implemented. The efficacy of the proposed control scheme was evaluated and demonstrated by means of the field test.

• Journal of Korean Society on Water Environment
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• v.28 no.5
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• pp.657-662
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• 2012

This study was carried out to evaluate the removal rate of organic and inorganic matters from landfill leachate using pre-treatment process as coagulation and limonite adsorption, and membrane process as RO (reverse osmosis) and NF(nanofiltration). By adding limonite adsorption as pre-treatment process, about 40% of organic matters in leachate was removed through pre-treatment process and 74.7% of boron was removed after RO process without pH adjustment. The rejection rate of boron in RO process mainly depends on the pH and increased at pH value of 10. RO process was performed as two stage system adjusting pH condtion to 7 and 10 in second RO stage for boron removal. Most (>90%) of TOC, Cl- and inorganic matters as Ca was rejected in first RO stage, the residue was rejected in second RO and the rejection rate was above 97%. Considering economic efficiency of operation cost, NF substituted for the first RO and total removal rate of TOC was above 90%. Through RO system toxicity to Daphnia in leachate was removed completely.

• Journal of Korean Academy of Nursing Administration
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• v.19 no.3
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• pp.414-426
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• 2013

Purpose: The purpose of this study was to identify the process of overcoming the intention toward turnover experienced by career nurses. Methods: Data were collected from 10 career nurses though in-depth interviews about their experiences. The main question was "How do you describe your experience of the process of overcoming intention to turnover as a career nurse?" Qualitative data from field and transcribed notes were analyzed using Strauss & Corbin's grounded theory methodology. Results: From the participants' statement, 127 concepts, 34 subcategories and 13 categories were extracted through the open coding process. The core category was discovered to be 'back to the original place'. Phenomenon was identified as 'reached the threshold that cannot be withstood' and this series of process was categorized as having four stages: 'conflict', 'meditation', 'discovery' and 'conquest'. There were three types of overcoming turnover intention in career nurses, 'adjustment', 'compromise', 'self-led'. Conclusion: The results of this study produced useful information about the needs of career nurses during the process of overcoming turnover intention based on their stage and overcoming types of turnover intension. Ultimately this study may help decrease the turnover intention of career nurses.