• International Journal of Contents
• /
• v.3 no.1
• /
• pp.1-8
• /
• 2007

The distributions of the minimum correlated F-variable arises in many applied statistical problems including simultaneous analysis of variance (SANOVA), equality of variance, selection and ranking populations, and reliability analysis. In this paper, negative binomial sampling technique is employed to derive the distributions of the minimum of chi-square variables and hence the distributions of the minimum correlated F-variables. The work presented in this paper is divided in two parts. The first part is devoted to develop some combinatorial identities arised from the negative binomial sampling. These identities are constructed and justified to serve important purpose, when we deal with these distributions or their characteristics. Other important results including cumulants and moments of these distributions are also given in somewhat simple forms. Second, the distributions of minimum, chisquare variable and hence the distribution of the minimum correlated F-variables are then derived within the negative binomial sampling framework. Although, multinomial theory applied to order statistics and standard transformation techniques can be used to derive these distributions, the negative binomial sampling approach provides more information regarding the nature of the relationship between the sampling vehicle and the probability distributions of these functions of chi-square variables. We also provide an algorithm to compute the percentage points of the distributions. The computation methods we adopted are exact and no interpolations are involved.

• The Journal of Asian Finance, Economics and Business
• /
• v.5 no.2
• /
• pp.43-51
• /
• 2018

We study the impact of economic policy uncertainty (EPU) of Asian four countries such as Korea, Japan, Hong Kong, and China on housing market returns in Korea. Also, we document the relationship between the EPU index of those four countries and the housing market including macroeconomic indicators in Korea. The EPU index of those four countries has significantly a negative effect on the housing purchase price index, housing lease price index in Korea. The EPU index in Korea and Japan has significantly a negative effect on the CPI. The EPU index in only Japan has significantly a negative effect on the PPI. The EPU index in Hong Kong and Korea has significantly a negative effect but the EPU index in China significantly has a positive effect on the stock price index in construction industry. The EPU index in only Korea has significantly a negative effect the stock price index in banking industry. This study shows the EPU index of the Korea has the negative relationships on the housing market economy rather than other countries by VECM. And this study has an important evidence of the spillover of several macroeconomic indicators in Korea for the EPU index of the Asian four countries.

• Research in Community and Public Health Nursing
• /
• v.30 no.4
• /
• pp.571-580
• /
• 2019

Purpose: The purpose of this study is to examine the mediating effects of emotional venting via instant messaging (IM) and positive emotion in the relationship between negative emotion and depression. Methods: Online survey was conducted in Korea between 2 April and 7 April 2019. To obtain samples with representativeness, data were gathered by the professional research firm. A total of 250 Koreans were participated in this study. The collected data were analyzed using descriptive statistics, Pearson's correlation coefficients, and SPSS PROCESS macro to test the mediating effects. Results: This study analyzed the direct/indirect effects of negative emotion on emotional venting via IM, in the relationship between positive emotion and depression. Negative emotion had indirect effects on depression through emotional venting via IM and positive emotion. Both emotional venting via IM and positive emotion had dual mediating effects in the influence of negative emotion on depression. Conclusion: These results suggest that it is important to manage negative emotion to prevent depression. Also, this study confirmed that emotional venting via IM is a powerful factor influencing emotional recovery.

• International Journal of Human Ecology
• /
• v.12 no.1
• /
• pp.15-24
• /
• 2011

This study investigated childhood eating behavior, the influence of eating behavior on the positive and negative emotionality of children, and the pattern or eating behavior influence on emotionality depending on the age and gender of children. A total of 202 children (ages 5 to 7) were selected from 3 nurseries and 1 kindergarten ill Seoul and the survey data responses from teachers were analyzed. The results were as follows. First, children with higher levels of eating behavior showed a higher positive emotionality score compared to those with lower levels of eating behavior. The effect of gender was not significant and positive emotionality tended to increase in the 5 and 6 year old groups as the level of eating behavior increased; in addition, it was generally similar in the 7 year old group. Second, the children with lower level, of eating behavior showed a higher negative emotionality score compared to those with higher levels of eating behavior. The main effects by age and gender were insignificant; however, the interaction of age and eating behavior affected the negative emotionality of children. The eating behavior of children affects emotionality and children with better eating behaviors showed more positive emotional responses and less negative emotional responses in the same circumstances.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.17 no.6
• /
• pp.546-552
• /
• 2012

This paper presents an active anti-islanding detection method using negative sequence voltage injection to the grid through a three-phase photovoltaic inverters. Because islanding operation mode can cause a variety of problems, the islanding detection of grid-connected photovoltaic inverter is the mandatory feature. The islanding mode is detected by measuring the magnitude of negative sequence impedance calculated by the negative sequence voltage and current at the point of common coupling. Simulation and experimental test are performed to verify the effectiveness of the proposed method which can detect the islanding mode in the specified time. The test has been done in accordance with the condition on IEEE Std 929-2000.

• Journal of Families and Better Life
• /
• v.28 no.5
• /
• pp.251-262
• /
• 2010

This study examines the relationship between a mother's psychological well-being and children's problematic behavior(withdrawal, depression anxiety, aggression and emotional instability). In order to expand the study on the relationships, special attention was given to the possible mediator effects of mother's coping style with children's negative emotions. The subjects were 305 mothers with children 4-5 years old residing in the cities of Cheonan and Seongnam. It was found that mother's psychological well-being was significantly related to the level of children's withdrawal, depression anxiety, aggression and emotional instability. The mother's coping style with children's negative emotions were also significantly related to the mother's psychological well-being. In addition the mother's coping style with children's negative emotions was found to be a significant mediator of the relationship between mother's psychological well-being and children's. This was especially so for internal problems behavior as like withdrawal, depression anxiety and emotional instability that were perfectly mediated by the mother's coping style with children's negative emotions. Aggression, external problems behavior was partially mediated by the mother's coping style.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.64 no.9
• /
• pp.1315-1322
• /
• 2015

This paper proposes an active islanding detection method for the BESS (Battery Energy Storage System) with 3-phase inverter which is connected to the AC grid. The proposed method adopts the DDSRF (Decoupled Double Synchronous Reference Frame) PLL (Phase Locked-Loop) so that the independent control of positive-sequence and negative-sequence current is successfully carried out using the detected phase angle information. The islanding state can be detected by sensing the variation of negative-sequence voltage at the PCC (Point of Common Connection) due to the injection of 2-3% negative-sequence current from the BESS. The proposed method provides a secure and rapid detection under the variation of negative-sequence voltage due to the sag and swell. The feasibility of proposed method was verified by computer simulations with PSCAD/EMTDC and experimental analyses with 5kW hardware prototype for the benchmark circuit of islanding detection suggested by IEEE 1547 and UL1741. The proposed method would be applicable for the secure detection of islanding state in the grid-tied Microgrid.

• Smart Structures and Systems
• /
• v.21 no.5
• /
• pp.653-668
• /
• 2018

This work proposes and investigates re-centering negative stiffness dampers (NSDs) for vibration suppression in high-speed trains. The merit of the negative stiffness feature is demonstrated by active controllers on a high-speed train. This merit inspires the replacement of active controllers with re-centering NSDs, which are more reliable and robust than active controllers. The proposed damper design consists of a passive magnetic negative stiffness spring and a semi-active positioning shaft for re-centering function. The former produces negative stiffness control forces, and the latter prevents the amplification of quasi-static spring deflection. Numerical investigations verify that the proposed re-centering NSD can improve ride comfort significantly without amplifying spring deflection.

• Journal of Korean Society of Forest Science
• /
• v.97 no.4
• /
• pp.423-430
• /
• 2008

Negative ion is considered as one of the forest health attributes. The overall purpose of this study was to investigate the influence of air negative ions on physiological effects. Data were collected from 12 volunteers (university students) who were randomly assigned into treatment and control groups. Subjects in treatment group were exposed to air with negative (2,001,000 ion/cc). Using pretest-posttest control group design, blood cortisol, norepinephrine, epinephrine, and cognitive function were measured. Data analysis indicated that negative ions influenced on positive effects of stress responses.

• The Research Journal of the Costume Culture
• /
• v.21 no.4
• /
• pp.562-575
• /
• 2013

The purpose of this study was to test the determinants of fashion savvy. As determinants, this study examined fear of negative evaluation by others and self esteem as subject-related variables and consumer confidence in fashion decisions as the product-related variable. It was hypothesized that fear of negative evaluation and self esteem influence fashion savvy both directly and indirectly through consumer confidence in fashion decisions. Data were gathered by surveying university students in Seoul metropolitan area, using convenience sampling, and 311 questionnaires were used in the statistical analysis. In analyzing data, factor analysis and path analysis were conducted. Tests of the hypothesized path show that one factor of fear of negative evaluation and self esteem influence fashion savvy directly and indirectly through consumer confidence in fashion decisions. More specifically, 'fear of negative impression and judgment' factor negatively influences 'marketing literacy' and 'consumer selfefficacy' of fashion savvy, whereas self-esteem positively influences 'consumer self-efficacy' of fashion savvy. In addition, consumer confidence in fashion decisions influences all six factors of fashion savvy. The implications of these findings and suggestions for future study are also discussed.