• The Journal of the Korea Contents Association
• /
• v.14 no.11
• /
• pp.743-758
• /
• 2014

The purpose of this study is to examine the mediating effect of economic stress in the relationship between Perceived Income Inequality and Suicidal Ideation among old adults. To achieve this objective, this study analyzed basic statistics, reliability, correlation, and regression (tolerance and variance inflation factor) with the help of SPSS ver. 18.0. using data of 532 elderlies over 65 years old who live in Jeollanam-do. The main study results were as follows. The result shows the significant medicating effect of economic stress in the relationship between Income Inequality and Suicidal Ideation. Based on these results, political and practical implications are proposed.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.28 no.5
• /
• pp.503-510
• /
• 2004

In this paper, the well-conditioned observer for a stochastic system is designed so that the observer is less sensitive to the ill-conditioning factors in transient and steady-state observer performance. These factors include not only deterministic uncertainties such as unknown initial estimation error, round-off error, modeling error and sensing bias, but also stochastic uncertainties such as disturbance and sensor noise. In deterministic perspectives, a small value in the L$_{2}$ norm condition number of the observer eigenvector matrix guarantees robust estimation performance to the deterministic uncertainties. In stochastic viewpoints, the estimation variance represents the robustness to the stochastic uncertainties and its upper bound can be minimized by reducing the observer gain and increasing the decay rate. Both deterministic and stochastic issues are considered as a weighted sum with a LMI (Linear Matrix Inequality) formulation. The gain in the well-conditioned observer is optimally chosen by the optimization technique. Simulation examples are given to evaluate the estimation performance of the proposed observer.

• 제어로봇시스템학회:학술대회논문집
• /
• 1994.10a
• /
• pp.28-33
• /
• 1994

An optimal controller, e.g. LQG controller, may not be realistic in the sense that the required control power may not be achieved by existing actuators, and the measured output is not satisfactory. To be realistic, the controller should meet such constraints as sensor or actuator limitation, performance limit, etc. In this paper, the lnput/Output Variance Constrained (IOVC) control problem will be considered from the viewpoint of mathematical programming. A dual version shall be developed to solve the IOVC control problem, whose objective is to find a stabilizing control law attaining a minimum value of a quadratic cost function subject to the inequality constraint on each input and output variance for a stabilizable and detectable plant. One approach to the constrained optimization problem is to use the Kuhn-Tucker necessary conditions for the optimality and to seek an optimal point by an iterative algorithm. However, since the algorithm uses only the necessary conditions, the convergent point may not be optimal solution. Our algorithm will guarantee a sufficiency.

• The Journal of Information Technology
• /
• v.3 no.2
• /
• pp.23-37
• /
• 2000

This study examines the effect of trade union on the structure of wage determining and the variance of wage in manufacturing and non-manufacturing, 1993, in Korea It finds that the wage determining mechanism is significantly different between union and nonunion establishments, and that the wage inequality is too significantly lower among workers in establishments that are unionized than among those that are not. However, it is not clear whether the union wage policies designed to standardize rates have the effects of reduction in wage variance. that is mostly because of smaller variance within unionized workers having the same wage determining characteristics.

• Journal of Korean Society of Forest Science
• /
• v.109 no.1
• /
• pp.99-108
• /
• 2020

Although the relationship between income and income inequality has previously been discussed, the present study applies a dynamic approach to analyze the specific relationship between forest household income and income inequality. For this analysis, a unit root test and a cointegration test were conducted to characterize the nature of income time-series data. After converting unstable time-series data into stable time-series data, a VAR model was estimated. Based on this model, an impulse-response was generated and variance-decomposition analysis was performed. These analyses showed that the effect of forest household income was relatively larger than that of the Gini coefficient, and that the impact of forest household income not only caused income to increase but also caused the Gini coefficient to decrease. In addition, the impact of the Gini coefficient had an impact on reducing forest household income and further increasing income inequality. We conclude that, with the aim of alleviating the inequality of forest household income, an income growth policy would be more effective than an income distribution policy.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.20 no.44
• /
• pp.257-261
• /
• 1997

Patents often serve as leading indicators of technological change. This patenting activity reflected R&D (Research & Development) of new technology. The purpose of this study is to set up a forecasting model that anticipate the number of domestic patent applications and the number of patents granted relating to R&D inputs (R&D expenditure, R&D manpower) at the level of three industrial sectors in Korea : electrical-electronic, machinery, chemical etc. In this study, forecasting models were used trend extrapolation and a set of regressions. Both Theil's inequality coefficient and MAE(Mean Absolute Error) were utilized to test the precision of predicted value. The patent data and the R&D data were based on Indicators of Industrial Technology data throught 1980 to 1996. The major results obtained in this study are as follows (1) The regression model is more useful for forecasting the trends of the number of patent applications and patents granted than the trend extrapolation method. (2) The variance of Theil's inequality is smaller in patent applications than in patent granted.

• Honam Mathematical Journal
• /
• v.46 no.2
• /
• pp.313-334
• /
• 2024

In the current study, our aim is to define new generalized extended beta and hypergeometric types of functions. Next, we methodically determine several integral representations, Mellin transforms, summation formulas, and recurrence relations. Moreover, we provide log-convexity, Turán type inequality for the generalized extended beta function and differentiation formulas, transformation formulas, differential and difference relations for the generalized extended hypergeometric type functions. Also, we additionally suggest a generating function. Further, we provide the generalized extended beta distribution by making use of the generalized extended beta function as an application to statistics and obtaining variance, coefficient of variation, moment generating function, characteristic function, cumulative distribution function, and cumulative distribution function's complement.

• Journal of the Korean Statistical Society
• /
• v.15 no.2
• /
• pp.87-96
• /
• 1986

Sequential estimation of parameters in a compound Poisson process whose jump sizes are one-parameter exponential class random variables is discussed. Cramer-Rao type information inequality is used as an efficiency cirterion. Unbiased estimators for certain parametric functions whose variance attain the lower bound are all characterized with the corresponding sampling plans.

• Journal of the Korean Society for Industrial and Applied Mathematics
• /
• v.4 no.1
• /
• pp.93-100
• /
• 2000

This paper deals with some fundamental matters pertaining to estimation of critical quantities associated with continuous processes which are frequently related to the quality rating of the product. Specifically, it examines bounds on estimation and bounds on the estimation error variance. It draws on recent results from the theory of mathematical inequalities and their applications.

• Journal of Labour Economics
• /
• v.37 no.3
• /
• pp.45-73
• /
• 2014

This study analyzes the effect of labor unions in Korean manufacturing industry on wage variance of men from 1988 to 2012. The results are as follows. Firstly, the wage variance within establishments is higher than that between establishments, and the wage variance between establishments in the non-union sector has increased significantly compared to that in the union sector since 2000. There is strong evidence that the latter is due to the solidarity wage policy of unions which has strengthened since the early 2000s. Secondly, the influence of labor unions on the wage structure within the union sector has gotten stronger recently despite the general drop in the labor union membership. Thirdly, since the mid-1990s labor unions have contributed to reducing the overall wage variance. It implies that decline in the unionization rate over the years in Korea is likely to have contributed to increasing wage inequality.