• Korean Journal of Child Studies
• /
• v.18 no.2
• /
• pp.131-148
• /
• 1997

The purpose of this study was to develop criterion scores for the Korean version of the Attachment Q-set. It further examined distribution of security of attachment scores of Korean infants and differences in attachment scores by the cultural background. The criterion scores of attachment security were developed by 8 judges who are knowledgable in attachment theory and research. They used the Q-set to describe behavior characteristics of ideally secure infants of 12 and 36 months of age. Distribution of the attachment scores was analyzed with 191 infants, compiled from 4 studies including infants selected for this study. The attachment security criterion scores developed for Korean infants correlated highly with the Waters' criterion scores (1987) for American infants, .90 for 12 months and .88 for 36 months of age. Correlations between attachment scores developed for 12-and 36-month-olds was .89. The attachment security scores of the Korean version was a little higher and more negatively skewed than scores calculated using the American criterion. There were significant differences in the security of attachment scores by socioeconomic background of the infants, but not with employment status of the mothers. Infants of nonemployed middle class mothers had significantly higher security of attachment scores than infants of nonemployed lower class mothers. Infants from lower class families had higher "difficulty" scores, and "enjoying physical contact" scores were higher among infants from the middle class.

• Communications for Statistical Applications and Methods
• /
• v.17 no.4
• /
• pp.493-505
• /
• 2010

Developing a test for independence of random variables X and Y against the alternative has an important role in statistical inference. Kochar and Gupta (1987) proposed a class of tests in view of Block and Basu (1974) model and compared the powers for sample sizes n = 8, 12. In this paper, we evaluate Kochar and Gupta (1987) class of tests for testing independence against quadrant dependence in absolutely continuous bivariate Farlie-Gambel-Morgenstern distribution, via a simulation study for sample sizes n = 6, 8, 10, 12, 16 and 20. Furthermore, we compare the power of the tests with that proposed by G$\ddot{u}$uven and Kotz (2008) based on the asymptotic distribution of the test statistics.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2010.06a
• /
• pp.111-111
• /
• 2010

The mold transformers have been widely used in underground substations in large building and have some advantages in comparison to oil-transformer, that is low fire risk, excellent environmental compatibility, compact size and high reliability. In addition, the application of mold transformer for outdoor is possible due to development of epoxy resin. The mold transformer generally has cooling duct between low voltage coil and high voltage coil. A mold transformer made by one body molding method has been developed for small size and low loss, but it needs some cooling method because heat radiation between each winding is difficult. In this paper, the temperature distribution and thermal stress analysis of H class 100kVA pole cast resin transformer for power distribution are investigated by FEM program.

• Journal of the Korea Society of Computer and Information
• /
• v.4 no.4
• /
• pp.170-176
• /
• 1999

This paper addresses the design of object distribution in distributed object-oriented databases. The proposed strategy of object distribution consists of two-step design of fragments. One step is class fragmentation and the other is allocation of fragments. We define partitioning algorithms to reflect the characteristics of object-oriented databases in the class fragmentation and define expressions to reduce the amount of data transfer by allocating fragments of other classes referred together to one site in the allocation of fragments

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.29 no.12
• /
• pp.33-39
• /
• 2015

This paper examines the insulation performance of synthetic air and dry air. This examination was conducted based on dielectric strength in uniform and non-uniform field, electric field distribution by interior structure and defects in gas insulation switchgear (GIS) and insulation performance in different temperatures. From this review, it was found that eco-insulation gas required to possess low moisture content for power equipment in the distribution class. The results of this paper are valuable to ensure the insulation design and insulation reliability of GIS using air.

• The Journal of the Korean dental association
• /
• v.15 no.9
• /
• pp.745-748
• /
• 1977

1,620 patients who visited our department from 1966 to 1977.7.15, were surveyed on the yearly tendency of patient distribution and the state of Angle's clssification. 1. There was increased visiting rate of patint a year. Patient distribution who visited in our department in the year 1976 was five 샤든 than that in the year 1966. 2. 10-15 age group was 41% in total visiting patient and 20 age over group was 20.4%. 3. Permanent dentition group was 66.2% among three dentitions but it was showedthe tendency that age group is lower year by year. 4. Class I malocclusion was 51.1% in total visiting patient, moreclass III maloulsion was prevalent than class II malocclusion.

• Communications for Statistical Applications and Methods
• /
• v.27 no.2
• /
• pp.163-175
• /
• 2020

We consider a wide class of general weakly-dependent processes, called ψ-weak dependence, which unify almost all weak dependence structures of interest found in statistics under natural conditions on process parameters, such as mixing, association, Bernoulli shifts, and Markovian sequences. For detecting the tail behavior of the weakly dependent processes, change point tests are developed by means of cumulative sum (CUSUM) statistics with the empirical distribution functions of sample extremes. The null limiting distribution is established as a Brownian bridge. Its proof is based on the ψ-weak dependence structure and the existence of the phantom distribution function of stationary weakly-dependent processes. A Monte-Carlo study is conducted to see the performance of sizes and powers of the CUSUM tests in GARCH(1, 1) models; in addition, real data applications are given with log-returns of financial data such as the Korean stock price index.

• Journal of Applied Reliability
• /
• v.18 no.3
• /
• pp.220-228
• /
• 2018

Purpose: The purpose of this study is to investigate the tail behavior of the life distribution which exhibits an increasing failure rate or other positive aging effects after a certain time point. Methods: We characterize the tail behavior of the life distribution with regard to certain reliability measures such as failure rate, mean residual life and reliability function and derive several stochastic properties regarding such life distributions. Also, utilizing an L-statistic and its asymptotic normality, we propose new nonparametric testing procedures which verify if the life distribution has an increasing tail failure rate. Results: We propose the IFR-Tail (Increasing Failure Rate in Tail), DMRL-Tail (Decreasing Mean Residual Life in Tail) and NBU-Tail (New Better than Used in Tail) classes, all of which represent the tail behavior of the life distribution. And we discuss some stochastic properties of these proposed classes. Also, we develop a new nonparametric test procedure for detecting the IFR-Tail class and discuss its relative efficiency to explore the power of the test. Conclusion: The results of our research could be utilized in the study of wide range of applications including the maintenance and warranty policy of the second-hand system.

• Proceedings of the KSRS Conference
• /
• v.2
• /
• pp.721-724
• /
• 2006

Among many sources of soil and water pollution, former mining regions also play an important role in distribution and scope of pollution. In response, KMRC has made an investigation into the status mine hazard at the abandoned metalliferous mine area in Korea. In this study, we analyzed distribution of mine hazards at abandoned metalliferous mines using GIS. We considered the distribution of mine hazards and its magnitude for each abandoned mine and displayed the mine hazard index (MHI) using GIS. We divided the MHI value for each mine into 5 classes, and displayed the first class as smallest point symbol and the last class as biggest point symbol. The biggest symbol shows the most serious status of mine hazards. This GIS function was included in the AMGIS system KMRS are running, and it would be helpful to make decision of reclamation priority at abandoned metalliferous mine area.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.23 no.8
• /
• pp.1907-1914
• /
• 1998

This paper proposes the adaptive connection admission cotrol using the variale MRR(measurement reflection ratio) and the distribution of the number of cells arriving during the fixed interval. This distribution is estimated from the measured number of cells arriving at the output buffer during the fixed interval and traffic parameters specified by user. MRR is varied by the difference of estimated distribution and measurement distribution. As MRR is adaptively varied by estimated distribution error of accepted connections, it quickly reduces estimation error. Also, the scheduling scheme is proposed for multiplexed traffic with various traffic characteristics. For each traffic class, this scheme estimates adaptively equivalent bandwidth and schedules according to equivalent bandwidth ratio of each traffic class, so it improves cell loss rate and link utilization.