• Journal of the Korean Society of Industry Convergence
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• v.5 no.1
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• pp.33-38
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• 2002

This paper proposes an efficient method for improving the performance of polynomial adaline using the dimension reduction of independent variables. The adaptive principal component analysis is applied for reducing the dimension by extracting efficiently the features of the given independent variables. It can be solved the problems due to high dimensional input data in the polynomial adaline that the principal component analysis converts input data into set of statistically independent features. The proposed polynomial adaline has been applied to classify the patterns. The simulation results shows that the proposed polynomial adaline has better performances of the classification for test patterns, in comparison with those using the conventional polynomial adaline. Also, it is affected less by the scope of the smoothing factor.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.103-103
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• 2009

In this study, in order to develop high power piezoelectric transformer, we compared the piezoelectric transformers dimension. The basic composition of piezoelectric ceramics is ternary $0.01Pb(Ni_{1/3}Nb_{2/3})O_3-0.08Pb(Mn_{1/3}Nb_{2/3})O_3-0.91Pb(Zr_{0.505}Ti_{0.495})O_3$. The voltage step up ratio of piezoelectric transformer showed the maximum value at the near of 81 kHz and increased according to the increase of load resistance.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.9
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• pp.870-877
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• 2009

This study provides how the Dimension Reduction (DR) method as an efficient technique for reliability analysis can acquire its increased efficiency when it is applied to highly nonlinear problems. In the highly nonlinear engineering systems, 4N+1 (N: number of random variables) sampling is generally recognized to be appropriate. However, there exists uncertainty concerning the standard for judgment of non-linearity of the system as well as possibility of diverse degrees of non-linearity according to each of the random variables. In this regard, this study judged the linearity individually on each random variable after 2N+1 sampling. If high non-linearity appeared, 2 additional sampling was administered on each random variable to apply the DR method. The applications of the proposed sampling to the examples produced the constant results with increased efficiency.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.11
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• pp.1051-1058
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• 2011

The military communication equipment is required the high reliability for operating adequate functions under severe conditions. This reliability is the essential element for the quality of the product, for the uncontrolled factors, such as the clearance, damage of the material, the reduction of stiffness, which are the designer is unable to handle. In this paper, the uncertainty for the dimension was supposed to the probability model for the military communication equipment, and the average of the objective function was minimized for reducing design uncertainty. The reliability-based design optimization which was implemented the limit state function was formulated into the mathematical model, so the reliable optimized structure was implemented than the base-line design.

• The Journal of Information Technology and Database
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• v.8 no.2
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• pp.61-69
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• 2001

System Integration Projects, especially in public sector, have a tendency of growing in size and duration. Under such environment the effects of IT personnel turnover becomes a serious problem. In addition a high rate of turnover hinders shill accumulation and competitiveness obtainment. In this research we explored the reasons of turnover by way of tracing IT personnel who have involved in large-scale SI projects and moved or quit before the completion of the projects. Based on previous research we identified three dimensions of variables that affected turnover : task-related dimension, human relations dimension, treatment-related dimension. We used these dimensions as a guideline for the interview and questioning exploration. Implications from the research for improving IT Personnel management are also elaborated.

• Korean Journal of Agricultural Science
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• v.38 no.3
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• pp.525-532
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• 2011

The aim of this study was to develop a portable electronic nose system for freshness measurement of meats, which could be an alterative of subjective measurements of human nose and time-consuming measurements of conventional gas chromatograph methods. The portable electronic system was o optimized by comparing the measurement sensitivity and hardware efficiency, such as power consumption and dimension reduction throughout two stages of the prototypes. The electronic nose systems were constructed using an array of four different metal oxide semiconductor sensors. Two different configurations of sensor array with dimension were designed and compared the performance respectively. The final prototype of the system showed much improved performance on saving power consumption and dimension reduction without decrease of measurement sensitivity of pork freshness. The results show the potential of constructing a portable electronic system for the measurement of meat quality with high sensitivity and energy efficiency.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.211-211
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• 2000

The multiple targets tracking problem has been one of main issues in the radar applications area in the last decade. Besides the standard Kalman filtering, various methods including the variable dimension filter, input estimation filter, interacting multiple model (IMM) filter, federated variable dimension filter with input estimation, probable data association (PDA) filter etc. have been proposed to address the tracking and sensor fusion issues. In this paper, two existing tracking algorithms, i.e. the IMMPDA filter and the variable dimension filter with input estimation (VDIE), are combined for the purpose of improving the tracking performance of maneuvering targets in clutter. To evaluate the tracking performance of the proposed algorithm, three typical maneuvering patterns i.e. Waver, Pop-Up, and High-Diver motions, are defined and are applied to the modified IMMPDA filter considered as well as the standard IMM filter. The smaller RMS tracking errors, in position and velocity, of the modified IMMPDA filter than the standard IMM filter are demonstrated through computer simulations.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2007.04a
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• pp.135-140
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• 2007

In this paper, an Improved Dimension Reduction(IDR) method is proposed for uncertainty quantification that employes Kriging interpolation technic. It has been acknowledged that the DR method is accurate and efficient for assessing statistical moments and reliability due to the sensitivity free feature. However, the DR method has a number of drawbacks such as instability and inaccuracy for problems with increased nonlineality. In this paper, improved DR is implanted by three steps. First, the Kriging interpolation method is used to accurately approximate the responses. Second, 2N+1 and 4N+1 ADOEs are proposed to maintain high accuracy of the method for UQ analysis. Third, numerical integration scheme is used with accurate but free response values at any set of integration points of the surrogated model.

• The International Journal of Costume Culture
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• v.5 no.3
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• pp.204-212
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• 2002

The purpose of this study is to find out relationships among Gender Body Ideology, and clothing preferences. Subjects consisted of 75 female elementary school students, 64 female high school students, and their mothers(139) who are currently residing in Daejeon, Korea. The research was a ex-post facto relational study and the instruments for the study were GBI, genderlogy and 24 clothing stimuli for measuring clothing preferences. The reliability and validity of the measuring instruments were verified by results of judge group analysis and pre-tests. The factor analysis of GBI emerged 4 major factors in Being dimension, and 4 major factors in Doing dimension. Medium low correlations existed between the two GBI dimensions, and genderlogy was correlated specially with the Being dimension. Two GBI dimensions and genderlogy effected on preferences and Possessions of some selected design elements, however, GBI showed higher Predicting power for clothing preference.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.507-510
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• 2003

In this paper, optical sensor system using PSD(Position Sensitive Detection) is proposed to obtain the three dimensional position of moving markers attached to human body. To find the coordinates of an moving marrer with stereo vision system, two different sight rays of an moving marker are required. Usually, those are acquired with two optical sensors synchronized at the same time. PSD sensor is used to measure the position of an incidence light in real-time. To get the three-dimension position of light source on moving markers, a conventional camera calibration method are used. In this research, we realized a low cost motion capture system. The proposed system shows high three-dimension measurement accuracy and fast sampling frequency.