• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.10a
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• pp.28-33
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• 2004

At present, industry and researchers are looking for ways to reduce the use of lubricants because of ecological and economical reasons. Therefore, metal cutting is to move toward dry cutting or semi-dry cutting. This paper presents an investigation into MQL(Minimum Quantity Lubrication) machining with the objective of deriving the optimum cutting conditions for the turning process of SM45C. To reach these goals several finish turning experiments were carried out, varying cutting speed, feed rate and oil quantity, with MQL. The surface roughness results of tests were measured and the effects of cutting conditions were analyzed by the method of Analysis of Variance(ANOVA). From the experimental results and ANOVA, it is found that a better surface roughness can be obtained by decreasing oil quantity and feed rate.

• Korean Journal of Adult Nursing
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• v.24 no.5
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• pp.531-539
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• 2012

Purpose: The purpose of this study was to identify the influencing factors associated to students nurses' cultural awareness toward immigrants for marriage and foreign workers. Methods: The participants were 107 nursing students in C city in Chungnam province. The data were collected with structured questionnaire. Collected data were analyzed using t-test, ANOVA, correlation analysis, and stepwise multiple regression. Results: The mean score of cultural awareness was 3.67. The degree of cultural awareness was different according to educational experience related multiculture and age. The variables predicting cultural awareness were social distance of foreign workers, emotions of immigrants for marriage and age. These factors accounted for 26% of the variance of cultural awareness in nursing students. Conclusion: The results indicate education related multiculture should be provided to nursing students to reduce the social distance between students and foreign workers and enhance positive emotions for immigrants.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05c
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• pp.27-30
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• 2002

In this paper, we were investigated leakage current properties of outdoor insulator on climatic environmental factor. Contamination is one of the most important factor to determine the performance of insulator. Thus, it is very important to exam the contamination degree on the outdoor insulator. There are many limits, such as reliability of data, interval of measurement and similarity of environmental conditions, in conventional method. So, we measured phase and leakage current of outdoor insulator using the temperature & humidity chamber. In this investigation, phase difference was measured to compare the variance of phase difference with the contamination degree and relative humidity.

• Journal of the Semiconductor & Display Technology
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• v.16 no.1
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• pp.59-64
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• 2017

The general manufacturing problem can be described as the achievement of a predefined product quality with given equipment, cost and time constraints. Unfortunately, for some quality characteristics of a product such as surface roughness it is hard to ensure that these requirements will be met. Stainless steels STS 304 is frequently used as shaft materials in small fiber reinforced polymer(FRP) fishing boats. In this work, the dry turning parameters of STS 304 are optimized by using Taguchi method. The experiments were conducted at three different cutting speeds with three different feed and three different depth of cut. The cutting parameters are optimized using signal to noise ratio and the analysis of variance. The effects of cutting speed and feed on surface roughness was analyzed. The results revealed that the spindle speed is the more significant parameter influencing the surface roughness.

• Industrial Engineering and Management Systems
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• v.9 no.1
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• pp.20-27
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• 2010

The purpose of this study was to compare the consistency of external ear measurements obtained by electronic digital caliper, photocopier scanning and digital photographic methods. Photogrammetric measurements were made after image editing software was used to optimize the brightness, contrast, size and image clarity. The CorelDRAW dimension tool was used to create a dimension line that measured the vertical and horizontal length between any two landmarks. Results of repeated measures analysis of variance revealed no significant differences in length and width of the pinna between the three methods. The reliability of the three measurement techniques showed a high degree of consistency. Further study and efforts could be extended to measurement hands, foots and facial dimensions by present techniques.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.45 no.3
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• pp.399-406
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• 1996

This paper presents a method of hierarchical state estimation of the time-varying linear systems via Block-pulse function(BPF). When we estimate the state of the systems where noise is considered, it is very difficult to obtain the solutions because minimum error variance matrix having a form of matrix nonlinear differential equations is included in the filter gain calculation. Therefore, hierarchical approach is adapted to transpose matrix nonlinear differential equations to a sum of low order state space equation from and Block-pulse functions are used for solving each low order state space equation in the form of simple and recursive algebraic equation. We believe that presented methods are very attractive nd proper for state estimation of time-varying linear systems on account of its simplicity and computational convenience. (author). 13 refs., 10 figs.

• Journal of Agricultural Extension & Community Development
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• v.18 no.4
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• pp.879-902
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• 2011

This study was conducted to investigate the levels of hope and their relationship with problem behavior, academic records and procrastination among rural adolescents. The participants were 579 rural middle and high school students from three counties. The major results of the study were as follows. First, pathway and agency thinking of rural adolescents were negatively correlated with depression and anxiety, and were positively correlated with academic records and procrastination. But only agency thinking of rural adolescents were negatively correlated with delinquency among problem behaviors. Second, as a result of multivariate analysis of variance, groups of high hope of rural adolescents were lower in depression and anxiety than groups of low hope, but were higher in academic records and procrastination.

• International Journal of Reliability and Applications
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• v.18 no.2
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• pp.65-82
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• 2017

Abstract. Camilo Dagum proposed several variants of a new model for the size distribution of personal income in a series of papers in the 1970s. He traced the genesis of the Dagum distributions in applied economics and points out parallel developments in several branches of the applied statistics literature. The main aim of this paper is to define a bivariate Dagum distribution so that the marginals have Dagum distributions. It is observed that the joint probability density function and the joint cumulative distribution function can be expressed in closed forms. Several properties of this distribution such as marginals, conditional distributions and product moments have been discussed. The maximum likelihood estimates for the unknown parameters of this distribution and their approximate variance-covariance matrix have been obtained. Some simulations have been performed to see the performances of the MLEs. One data analysis has been performed for illustrative purpose.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.12 no.3
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• pp.193-197
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• 2012

This paper focuses on identifying which appliance is currently operating by analyzing electrical load signature for home energy monitoring system. The identification framework is comprised of three steps. Firstly, specific appliance features, or signatures, were chosen, which are DC (Duty Cycle), SO (Slope of On-state), VO (Variance of On-state), and ZC (Zero Crossing) by reviewing observations of appliances from 13 houses for 3 days. Five appliances of electrical rice cooker, kimchi-refrigerator, PC, refrigerator, and TV were chosen for the identification with high penetration rate and total operation-time in Korea. Secondly, K-NN and Naive Bayesian classifiers, which are commonly used in many applications, are employed to estimate from which appliance the signatures are obtained. Lastly, one of candidates is selected as final identification result by majority voting. The proposed identification frame showed identification success rate of 94.23%.

• Journal of Korean Critical Care Nursing
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• v.16 no.3
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• pp.73-86
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• 2023

Purpose : This study aimed to identify the factors affecting the quality of life of lung transplant patients. Method : The participants were patients who received lung transplants at a general hospital in City Y. Data were collected through structured questionnaires from June 2023 to August 2023. General characteristics, lung transplantation-related characteristics, quality of life, functional disability, treatment compliance, social support, anxiety, and depression-were measured. For data analysis, hierarchical multiple regression was performed using SPSS/WIN 29.0. Results : In the final model, quality of life was associated with income, self-help group attendance, functional disability, social support, treatment compliance, and anxiety and depression. Together, they explained 61.2% of the total variance in the results. Conclusion : Our findings suggest that improving lung transplant patients' quality of life requires active intervention in stress management to perform treatment instructions well, a social support system that can help them financially, and encouraging and participating in social activities as patients.