• Journal of the Korean Mathematical Society
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• v.61 no.1
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• pp.133-147
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• 2024

Let G = (V, E) be a connected finite graph. We study the existence of solutions for the following generalized Chern-Simons equation on G $${\Delta}u={\lambda}e^u(e^u-1)^5+4{\pi}\sum_{s=1}^{N}\delta_{ps}$$, where λ > 0, δ_ps is the Dirac mass at the vertex p_s, and p₁, p₂, . . . , p_N are arbitrarily chosen distinct vertices on the graph. We show that there exists a critical value $\hat{\lambda}$ such that when λ > $\hat{\lambda}$, the generalized Chern-Simons equation has at least two solutions, when λ = $\hat{\lambda}$, the generalized Chern-Simons equation has a solution, and when λ < $\hat{\lambda}$, the generalized Chern-Simons equation has no solution.

• Journal of Korean Medicine Rehabilitation
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• v.20 no.4
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• pp.105-130
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• 2010

Objectives : The purpose of this study was to assess the statistical methods errors used in the journal of Oriental Rehabilitation Medicine(JORM) and to identify the types of errors in statistical analysis. Methods : We reviewed quantitative articles that were published in the JORM from January 2005 through October 2009. Those were not used by statistical analysis such as literature studies, case study, review articles were not included in this analysis. A total of 296 articles was reviewed. We evaluated the adequacy and the validity of the statistical techniques with our checklist established be modified Lee's checklist, and three statistical evaluators assessed together to minimize bias. Results : Of the 222 articles, 213 were used in inferential and descriptive statistics. Of those 80% of articles adopting descriptive and inferential statistics were detected having statistical errors. One articles used 1.7 statistical method unit generally. Most frequently employed statistics were student t-test, one way ANOVA. pearson correlation analysis, Mann-whitney U test, paired t-test, and chi-square test in their order. However, most frequent statistics having errors were similar in order. The most common statistic errors were as follow: 1. absence of normality test, 2. misuse between paired test and unpaired test, 3. wrong choice of repeated measures analysis without consideration of time variables, 4, increase of Type I error by using inappropriate multiple test, 5. inappropriate application of discrete or categorical data instead of continuous data in correlation analysis, 6. poor consideration of basic consumption in chi-square test, 7. confusion between frequency comparison and average comparison, 8. mentioning the statistical technique without using it. Conclusions : We found various mistake or misuses in the applications of statistical methodologies in the articles published in the JORM. Careful consideration of statistical use and review from the specialist of statistics are warranted for improving the quality of JORM.

• Journal of Korea Multimedia Society
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• v.23 no.12
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• pp.1464-1475
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• 2020

Due to the spread of COVID-19, the online lecture has become more prevalent. However, it was found that a lot of students and professors are experiencing lack of communication. This study is therefore designed to improve interactive communication between professors and students in real-time online lectures. To do so, we explore deep learning approaches for automatic recognition of students' facial expressions and classification of their understanding into 3 classes (Understand / Neutral / Not Understand). We use 'BlazeFace' model for face detection and 'ResNet-GRU' model for facial expression recognition (FER). We name this entire process 'Degree of Understanding (DoU)' algorithm. DoU algorithm can analyze a multitude of students collectively and present the result in visualized statistics. To our knowledge, this study has great significance in that this is the first study offers the statistics of understanding in lectures using FER. As a result, the algorithm achieved rapid speed of 0.098sec/frame with high accuracy of 94.3% in CPU environment, demonstrating the potential to be applied to real-time online lectures. DoU Algorithm can be extended to various fields where facial expressions play important roles in communications such as interactions with hearing impaired people.

• Journal of the Korean Home Economics Association
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• v.41 no.9
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• pp.105-120
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• 2003

This study has conducted to develop the computer program for households portfolio management to enhance their financial well-being. The study has divided into two parts. First, descriptive statistics has used to analyze as a basis of computer program and it includes the comparison of household asset allocations between households in Korea and U. S. A., Second, it shows the components of the portfolio program developed to manage households efficiently. For both two countries, recent four years data has been used and in part two, total sample size of households in Korea is 2155. From the statistical analysis, households in U. S. A. tend to invest more on the stock & bonds as their net-asset is increased. However households in Korea tend to have less financial assets and it might be found the fact that they prefer to own real-estate because of the inflation. In the part of computer program, it is included the average financial asset responding to the demographic variables and households could refer those average amount as a reference planning their asset portfolio.

• Proceedings of the KSME Conference
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• 2002.08a
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• pp.479-482
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• 2002

Riblets with longitudinal grooves along the streamwise direction have been used as an effective flow control technique for drag reduction. A flexible micro-riblet with v-grooves of peak-to-peak spacing of $300{\mu}m$ was made using a MEMS fabrication process of PDMS replica. The flexible micro-riblet was attached on the whole surface of a NACA0012 airfoil with which grooves are aligned with the streamwise direction. The riblet surface reduces drag coefficient about $7.9{\%}\;at\;U_o=3.3m/s$, however, it increases drag about $8{\%}\;at\;U_o=7.0m/s$, compared with the smooth airfoil without riblets. The near wake has been investigated experimentally far the cases of drag reduction ($U_o\;=\;3.3 m/s$) and drag increase ($U_o\;=\;7 m/s$). Five hundred instantaneous velocity fields were measured for each experimental condition using the cross-correlation PIV velocity field measurement technique. The instantaneous velocity fields were ensemble averaged to get spatial distribution of turbulent statistics such as turbulent kinetic energy. The experimental results were compared with those of a smooth airfoil under the same flow condition. The micro-riblet surface influences the near wake flow structure largely, especially in the region near the body surface

• Korean Journal of Rural Living Science
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• v.7 no.1
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• pp.1-10
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• 1996

Recently, the population of Asian people has increased constantly in the United States., but appearances, culture and thoughts of Asian people are different with Americans in various ways, especially body shapes. Despite the recent developments in apparel size ranges in U. S. A., few changes have been made in sizing for Asian Women. Size ranges designed for Asian Women are not available on the mass market in U. S. A. They have many difficulties in finding clothing that fits well. Especially they do experience such as clothing problems in varying degrees. Therefore this research was designed to investigate the specific clothing problems of Asian Women in relation with size and fit, Asian Women's present means of resolving their clothing problems in U. S. A. 60 Asian Women in Twin cities, Minnesota were interviewed during the period of October, 1991. Data were analyzed by descriptive statistics for demographic information on the selected sample and the chi-square test for relationships between the independent variables and clothing problems. The results indicated that most respondents had shopped in a department store and 38.3% of the respondents answered rarely-fit of suit. Also 40% of the respondents answered that pants length was too long. There were significant relationships between the demographic variables i.e. age, marital status, occupation, height and clothing problems of Asian women.

• The Journal of Asian Finance, Economics and Business
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• v.5 no.2
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• pp.15-24
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• 2018

The study examines the magnitude of economic spillover and the impact of foreign direct investment (FDI) inflows on the efficiency of the bank industry in China. This study employs unit root tests, cointegration tests and cointegrating regression analysis, including fully modified ordinary least squares (FMOLS), canonical cointegrating regression (CCR) and dynamic OLS (DOLS) to test the proposed hypotheses. The sample is restricted to the period of time in which monthly data is available and comparable among variables for the period from January 2002 to October 2013 (142 observations). All of the time series data was collected and retrieved from the People's Bank of China, China Monthly Statistics from the National Bureau of Statistics of China, and International Financial Statistics database from International Monetary Fund. The results of the Johansen cointegration test suggest that there is a long-run equilibrium relationship between FDI inflows, foreign exchange rate and banks performance in China. The results of cointegrating regression analysis using FMOLS, CCR and DOLS suggest that M2 supply and FDI inflows are significant at the 0.01 level. The results confirm that FDI inflows in the banking sector are positively related to the increase of banks productivity and performance and short-term loans in China. However, the results suggest that Chinese Yuan currency exchange rate to U.S. dollar is not significant in the banking and financial industry of China.

• Communications for Statistical Applications and Methods
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• v.16 no.1
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• pp.31-40
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• 2009

Spatial time series data can be viewed either as a set of time series collected simultaneously at a number of spatial locations. In this paper, We estimate the parameters of spatial time autoregressive moving average (SIARMA) process by method of Gibbs sampling. Finally, We apply this method to a set of U.S. Mumps data over a 12 states region.

• The Korean Journal of Applied Statistics
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• v.22 no.5
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• pp.1047-1057
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• 2009

The nonparametric bivariate two-sample test of Bennett (1967) is extended to the multivariate k sample test. This test has been easily modified for a monotone trend among k samples. Often in applications it is important to consider a set of multivariate response variables simultaneously, rather than individually, and also important to consider testing k samples altogether. Different approaches of estimating the null covariance matrices of the test statistics resulted in the same limiting form. The multivariate k sample test is applied to the non-normal data of a randomized trial conducted for a period of four weeks in mental hospitals. The purpose of the trial is to compare the efficacy of three different interventions for a relief of the frequently occurring problems of constipation, caused as a side effect of antipsychotic drugs during hospitalization. The bowel movement status of patient for a week is summarized into a single severity score, and severity scores of four weeks comprise a four-dimensional multivariate variable. It is desirable with this trial data to consider a multivariate testing among k samples.

• Journal of the Korean Statistical Society
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• v.20 no.2
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• pp.202-207
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• 1991

In Le Cam's earlier work on superefficiency, it is proved that if an estimate is superefficient at a given paramter value $\theta$$\_$0/, then there must exist an infinite sequence {$\theta$$\_$n/}) of values(conversing to $\theta$$\_$0/) at which this estimate is worse than M. L. E. for certain classes of loss functions. For one-dimensional cases, these classes of lass functions include squared error loss. However. for multi-dimensional cases, they do not. This note is to give an example where a superefficiest estimator of a multi-dimensional parameter is not inferior to M. L. E. along any sequence ($\theta$$\_$n/) converging to the point of superefficiency with respect to the squared error loss.