• The Transactions of the Korea Information Processing Society
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• 제7권7호
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• pp.2254-2263
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• 2000

This paper proposes an efficient predictive image-compression technique based on vector quantization of blocks of pels. In the proposed method edge contents of blocks control the selection of predictors and block shapes as well. The maximum number of bits assigned to quantizers has been in creased to 3bits/pel from 1/5bits/pel, the setting employed by forerunners in predictive vector quantization of images. This increase prevents the saturation in SNR observed in their results in high bit rates. The variable block shape is instrumental in eh reconstruction of edges. The adaptive procedure is controlled by means of he standard deviation ofp rediction errors generated by a default predictor; the standard deviation address a decision table which can be set up beforehand. eh proposed method is characterized by overall improvements in image quality over A-VQ-PE and A-DCT VQ, both of which are known for their efficient use of vector quantizers.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
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• pp.365-368
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• 2000

This paper proposes a new heuristic method of constructing process capability indices (PCIs) for skewed populations. It is based on weighted standard deviation (WSD) method which decomposes the standard deviation of a quality characteristic into upper and lower deviations and adjusts the value of PCI using decomposed deviations in accordance with the skewness estimated from sample data. For symmetric populations, the proposed PCIs reduce to standard PCIs. Asymptotic distributions of the estimators of the PCIs are obtained. The performances of the proposed methods are compared with those of the standard and other methods. Numerical comparisons indicate that considerable improvements over existing methods can be achieved by the use of WSD method when the underlying distribution is skewed.

• Journal of Korean Society of Industrial and Systems Engineering
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• 제18권36호
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• pp.275-285
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• 1995

In recent years there has been increasing interest in the issue of process centering in manufacturing process, The traditional process capability indices Cp, Cpk and Cpu are used to provide measure of process performance, but these indices do not represent the issue of process centering. A new measure of the process capability index Cpm is proposed that takes into account the proximity to the target value as well as the process variation when assessing process performance. However, Cpm only considers acceptance cost for deviation from target value within specification limits, do not includes economic consideration for rejected items. This paper proposes flexible process performance measures that considered quadratic loss function caused by quality deviation within specification limits, rejection cost associated with the disposition of rejected items, and inspection cost. In this model disposition of rejected items are considered under perfect corrective procedures and the absence of perfect corrective procedures.

• Journal of the Institute of Convergence Signal Processing
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• 제13권2호
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• pp.63-69
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• 2012

Noise is regarded as an unwanted component of the image because it significantly reduces image quality. And image is often corrupted by mixed noise. In this paper an efficient modified weighted filter algorithm which combines spatial weight and intensity weight is proposed for removing mixed noise. In the proposed method, the filtering mask is separated into the four sub-windows and the parameters of the weights are confirmed by calculating local standard deviation and the mean of four sub-windows' standard deviations. Considering the spatial information and intensity information, the proposed method has good performance on not only noise elimination but also preservation of details. Simulation results demonstrate that the proposed method performs better than conventional algorithms.

• Journal of Korean Academy of Fundamentals of Nursing
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• 제19권2호
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• pp.179-189
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• 2012

Purpose: The purpose of this study was to identify the effects of eating habits, activities of daily living and health behaviors on oral health related-quality of life in elders. Methods: The sample consisted of 246 people 65 years or older. Data were analyzed using frequency, percentage, average standard deviation, t-test, ANOVA, Scheff$\acute{e}$, Pearson Correlation Analysis and Hierarchical Multiple Regression. Results: The control variables such as gender, presence of a spouse, subjective health status, presence of chronic disease and existing number of teeth explained 14% (F=7.76, p<.001) of variance in oral health related-quality of life. The control variables, eating habits, activities of daily living and health behaviors collectively explained 20% of variance in oral health related quality of life. Conclusions: The factors that influence oral health related quality of life were presence of spouse presence factor, existing number of teeth and health behavior. Therefore, oral health related quality of life of elders requires the development of programs to boost the quality of life, and help the elderly people to maintain existing number of teeth by focusing on the variety of characteristics.

• Journal of Korean Academy of Fundamentals of Nursing
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• 제17권2호
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• pp.231-239
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• 2010

Purpose: The purpose of this study was to explore the relationships between Yangsaeng and quality of life (WHOQOL-BREF) of Korean adults and older people practicing Dan Jeon Breathing. Methods: The participants were 133 adults and elderly people practicing Dan Jeon Breathing. Data were collected by self-reported questionnaires, which were constructed to include Yangsaeng and quality of life (WHOQOL-BREF). Frequency, percentage, mean standard deviation, t-test, ANOVA, Scheffe test, Pearson correlation coefficient, and Cronbach ${\alpha}$ value were used with the SPSS 14.0 win program to analyze the data using for finding. Results: Significant differences in Yangsaeng were evident on the basis of age, gender, duration of DJB, regular practice of DJB, and other exercises. There were significant differences in quality of life in terms of existence of spouse and duration of DJB. Also, all subcategories in Yangsaeng were positively related to all domain of quality of life. Conclusion: The results indicate that the quality of life of adult and elderly Koreans who practice DJB is more closely associated with Yangsaeng. Therefore, Dan Jeon Breathing can be utilized as a nursing intervention for Yangsaeng and quality of life of Koreans.

• Journal of Korean Clinical Nursing Research
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• 제15권2호
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• pp.127-138
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• 2009

Purpose: The purpose of this study was to explore self-reported perceived stigma, self-efficacy, and quality of life among psychiatric outpatients Methods: In the present study, researchers analyzed the survey responses of 195 patients recruited in the S hospital psychiatry outpatient clinic. The measurement tools used in this study were the "Devaluation & Discrimination" scale to determine perceptions of stigmatization, general and social efficacy scales to measure self-efficacy, and the "General Well-Being Index" to measure quality of life in psychiatric outpatient. Statistical analysis included means with standard deviation, t-test, ANOVA and Pearson correlation coefficients to identify relationships between the variables. Results: There was a significant difference in self-perceived stigma and quality of life in psychiatric outpatients (r=-.233, p=.001) and a negative correlation between self-efficacy and quality of life (r=-.424, p=.000). Correlation analysis results support the hypothesis that higher self-perceived stigma scores were related to reduced quality of life among patients with schizophrenia (r=-.231, p=.021), while there was a positive correlation between self-perceived stigma scores and self-efficacy scores among patients with bipolar disorder (r=.362, p=.013). Conclusion: The findings suggest that nursing imtervention strategies should include education programs to reduce stigmatization and enhance self-efficacy and quality of life among patients with chronic psychiatric illnesses.

• Journal of the Computational Structural Engineering Institute of Korea
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• 제21권5호
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• pp.413-419
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• 2008

Deterministic design optimization (DO) does not explicitly deal with a variety of factors from inherent randomness and uncertainties. Reliability based design optimization(RBDO) is necessary to use in engineering systems in order to guarantee quality and performance of product. In this paper, design variables are considered as random variables. Standard deviation according to change of design variables have changed as much as coefficient of variation. And, if the standard deviation is error of manufacturing, standard deviation-mean relation is concave form. We obtain reliability index using advanced first order second moment method(AFOSM). This paper is examined by solving two examples and the results are compares with DO, RBDO and suggested RBDO.

• Fibers and Polymers
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• 제7권4호
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• pp.404-413
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• 2006

This study examines multiple quality optimization of the injection molding for Polyether Ether Ketone (PEEK). It also looks into the dimensional deviation and strength of screws that are reduced and improved for the molding quality, respectively. This study applies the Taguchi method to cut down on the number of experiments and combines grey relational analysis to determine the optimal processing parameters for multiple quality characteristics. The quality characteristics of this experiment are the screws' outer diameter, tensile strength and twisting strength. First, one should determine the processing parameters that may affect the injection molding with the $L_{18}(2^1{\times}3^7)$ orthogonal, including mold temperature, pre-plasticity amount, injection pressure, injection speed, screw speed, packing pressure, packing time and cooling time. Then, the grey relational analysis, whose response table and response graph indicate the optimum processing parameters for multiple quality characteristics, is applied to resolve this drawback. The Taguchi method only takes a single quality characteristic into consideration. Finally, a processing parameter prediction system is established by using the back-propagation neural network. The percentage errors all fall within 2%, between the predicted values and the target values. This reveals that the prediction system established in this study produces excellent results.

• Proceedings of the Korean Association for Survey Research Conference
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• 한국조사연구학회 2002년도 추계학술대회 발표논문집
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• pp.111-127
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• 2002

As the utilization of official statistics has been recently increased, the necessity of objective quality assessment also has been increased. Since mean square error(MSE) and response rate, which have been considered as representative quality indicators in the past, may have the limits of use, it has been demanded to develop new quality indicators which are able to reflect the various requirements of users. In this paper, regarding sample surveys conducted by governmental agencies, the flow of procedures in statistics production is analyzed using input-output of each procedure. As the result, how to identify and develop quality indicators for each procedure is discussed, with some instances of indicators. Finally, the quality index using the results of quality assessment would be calculated based on a weighting method by the size of deviation of statistical measures.