• Journal of the Korea Safety Management & Science
• /
• v.12 no.3
• /
• pp.333-339
• /
• 2010

Data mining is the process of finding and analyzing data from a big database and summarizing it into useful information for a decision-making. A variety of data mining techniques have been being used for wide range of industries. One application of those is especially so for gathering meaningful information from process data in manufacturing factories for quality improvement. The purpose of this paper is to provide a methodology to improve manufacturing quality of fuel tanks which are auto-parts. The methodology is to analyse influential attributes and establish a model for optimal manufacturing condition of fuel tanks to improve the quality using decision tree, association rule, and feature selection.

• Journal of the Korean Society for Industrial and Applied Mathematics
• /
• v.19 no.4
• /
• pp.417-428
• /
• 2015

Although, in general, the random fluctuation of interest rates gives a limited impact on portfolio optimization, their stochastic nature may exert a significant influence on the process of selecting the proportions of various assets to be held in a given portfolio when the stochastic volatility of risky assets is considered. The stochastic volatility covers a variety of known models to fit in with diverse economic environments. In this paper, an optimal strategy for portfolio selection as well as the smoothness properties of the relevant value function are studied with the dynamic programming method under a market model of both stochastic volatility and stochastic interest rates.

• Mycobiology
• /
• v.29 no.3
• /
• pp.132-134
• /
• 2001

Since it is known that Agrobacterium tumefaciens, which has long been used to transform plants, can transfer the T-DNA to yeast Saccharomyces cerevisiae during tumourigenesis, a variety of fungi were subjected to transformation to improve their transformation frequency. In this study, I report the A. tumefaciens-mediated transformation of filamentous fungus Aspergillus niger. Transfer of the binary vector pBIN9-Hg, containing the bacterial hygromycin B phosphotransferase gene under the control of the Aspergillus nidulans trpC promoter and terminator as a selectable marker, led to the selection of $50{\sim}100$ hygromycin B-resistant transformants per $1{\times}10^7$ conidia of A. niger. This efficiency is improved $10{\sim}20$ fold more than reported elsewhere. In order to avoid the difficulties in selection transformant from the over-growing non-transformant, I used top agar containing 900 ${\mu}g/ml$ of hygromycin. Genomic PCR and Southern analysis showed that all transformants contained single T-DNA insert per fungal genome. This technique offers an easier and more efficient method than that of using protoplast.

• Proceedings of the KSRS Conference
• /
• 2003.11a
• /
• pp.1390-1392
• /
• 2003

The arid regions of western China are currently the focus of extensive exploration and development. This paper reports on recent experience gained by Chinese and Canadian project team members in the use of a variety of Earth observation satellite imagery for oil exploration and environmental assessment exercises in the Kuche area of Xinjiang. Through careful archival data selection and more recent data acquisition schemes, we have established several time series of MODIS, Landsat and Radarsat imagery in order to obtain a better understanding for daily, seasonal as well as decadal changes of the natural environment as well as man-made environmental features.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2014.05a
• /
• pp.323-325
• /
• 2014

SNOMED CT is a standard clinical terminology which is to efficiently record, manage and utilize clinical records during clinical processes. However, huge expressive power of SNOMED CT makes it difficult to select appropriate terms during short consultation hours. In addition, true meaning of a written record using the terminology may be misunderstood or even distorted since one clinical meaning could be expressed in a variety of ways. This paper analyzes such known problems in a database point of view, and presents effective selection methods of similar terminologies to mitigate the problem.

• IE interfaces
• /
• v.18 no.4
• /
• pp.370-381
• /
• 2005

This study is concerned with seeking the optimal allocation(disposition) for maximizing utility of consolidating old fashioned and new air defense weapon system like SAM-X(Patriot missile) and developing efficient solution algorithm based on simulated annealing(SA) algorithm. The SED(selection by effectiveness degree) procedure is implemented with an enhanced SA algorithm in which neighboring solutions could be generated only within the optimal feasible region by using a specially designed PERTURB function. Computational results conducted on the problem sets with a variety of size and parameters shows the significant efficiency of our SED algorithm over existing methods in terms of both the computation time and the solution quality.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.15 no.3
• /
• pp.83-90
• /
• 2001

This paper resents an algorithm for the optimal parameter selection of a power system stabilizer in a single machine-infinite bus system through the external equivalent transmission line. This method is one of the classical techniques by changing the PSS gain to allocate properly pole-zero positions. All the PSS parameters are obtained by solving a set of algebraic equations for the system constants depend on a variety of machine loadings and system external impedances, the natural oscillation modes, and the damping characteristics. And this algorithm was written in a simple software program using MATLAB.

• Proceedings of the Korea Inteligent Information System Society Conference
• /
• 2001.01a
• /
• pp.224-229
• /
• 2001

When a semiconductor package is assembled, various materials such as die attach adhesive, lead frame, EMC (Epoxy Molding Compound), and gold wire are used. For better preconditioning performance, the combination between the packaging materials by studying the compatibility of their properties as well as superior packaging material selection is important. But it is not an easy task to find proper packaging material sets, since a variety of factors like package design, substrate design, substrate size, substrate treatment, die size, die thickness, die passivation, and customer requirements should be considered. This research applies case-based reasoning(CBR) technique to solve this problem, utilizing prior cases that have been experienced. Our particular interests lie in building decision support model to aid the selection of proper die attach adhesive. The preliminary results show that this approach is promising.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.51 no.4
• /
• pp.160-166
• /
• 2002

Since conventional mobile robot control with one module has limitation to solve complex problems, there have been a variety of works on combining multiple modules for solving them. Recently, many researchers attempt to develop mobile robot controllers using artificial life techniques. In this paper, we develop a mobile robot controller using cellular automata based neural networks, where complex tasks are divided to simple sub-tasks and optimal neural structure of each sub-task is explored by genetic algorithm. Neural network modules are combined dynamically using the action selection mechanism, where basic behavior modules compete each other by inhibition and cooperation. Khepera mobile robot simulator is used to verify the proposed model. Experimental results show that complex behaviors emerge from the combination of low-level behavior modules.

• IEMEK Journal of Embedded Systems and Applications
• /
• v.5 no.1
• /
• pp.39-45
• /
• 2010

As wireless sensor network are being deployed in a wide variety of application areas, the number of sensor nodes in a sensor filed becomes larger and larger. In the past, ISP (In-System Programming) method have been generally used for code update but the large number of sensor nodes requires a new code update method called network reprogramming. There are many challenging issues for network reprogramming since it can make an impact on the network lifetime. In this paper, a new sender selection scheme for network reprogramming protocol is proposed to decrease energy consumption for code update by minimizing overlapped area between sender nodes and reducing data contention. Simulation results show that the proposed scheme can reduce the amount of message traffic and the overall data transmission time.