• Journal of the Korean Data and Information Science Society
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• v.26 no.4
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• pp.781-790
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• 2015

The Parrondo paradox is the counter-intuitive phenomenon: when we combine two losing games we can win the game or when we combine two winning games we can lose the game. In this paper, we assume that an investor adopts the rule of the history-dependent Parrondo game for investment in the stock market. Using the KRX (Korea Exchange) data from 2012 to 2014, we found the Parrondo paradox in the stock trading: the redistribution of profits among accounts can turn the decrease of the expected cumulative profit into the increase of the expected cumulative profit. We also found that the opposite case, namely the reverse Parrondo effect, can happen in the stock trading.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.5
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• pp.465-473
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• 2010

As increase of height and slenderness of buildings, serviceability design criteria such as maximum lateral drift and wind-induced vibration level play an important role in structural design of high-rise buildings. Especially, wind-induced vibration is directly related to discomfort of occupants. However, no practical algorithm or design method is available for structural designers to control the acceleration level due to wind. This paper presented a control method for wind-induced vibration of high-rise buildings using the resizing algorithm. The level of vibration due to wind is calculated by well known estimation rules of ASCE 7-02, NBCC 95, SAA83, and Solari method. Based on the fact that the level of wind-induced vibration is inversely proportional to the magnitude of natural periods of buildings, in the design method, natural periods of a high-rise building are modified by redistribution of structural weight according to the resizing algorithm. The design method is applied to wind-induced vibration control design of real 42-story residential building and evaluated the efficiency and effectiveness.

• Journal of the Earthquake Engineering Society of Korea
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• v.13 no.2
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• pp.59-68
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• 2009

For safe and economical design to provide strong earthquake resistance, the moment redistribution and plastic rotation of structures and their members needs to be evaluated. To achieve this, an earthquake design method was developed using secant stiffness analysis. To address the variation of member stiffness due to plastic rotation and moment redistribution, a structure was modeled with a beam-column element with non-rigid end connections (NREC element). Secant stiffness for the NREC element was determined based on the ductility demands of the structure and members. By performing a conventional linear analysis for the secant stiffness model, redistributed moments and plastic rotations of the members were computed. The proposed method was applied to a moment frame and two dual systems. The design results were verified using detailed nonlinear analyses.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.420-423
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• 2015

This paper proposes a method of non-linearity error detection and calibration for binary-weighted charge-driven DACs. In general, the non-linearity errors of DACs often occur due to the mismatch of layout designs or process variation, even when careful layout design methods and process calibration are adopted. Since such errors can substantially degrade the SNDR performance of DAC, it is crucial to accurately measure the errors and calibrate the design mismatches. The proposed method employs 2 identical DAC circuits. The 2 DACs are sweeped, respectively, by using 2 digital input counters with a fixed difference. A comparator identifies any non-linearity errors larger than an acceptable discrepancy. We also propose a calibration method that can fine-tune the DAC's capacitor sizes iteratively until the comparator finds no further errors. Simulations are presented, which show that the proposed method is effective to detect the non-linearity errors and calibrate the capacitor mismatches of a 12-bit DAC design of binary-weighted charge-driven structure.

• Journal of KIISE:Computer Systems and Theory
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• v.26 no.9
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• pp.1064-1072
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• 1999

The well-known Dimension Exchange Method(DEM) to quantized loads may result in difference in assigned loads to processors as large as logn~units, in the worst case, after balancing for a hypercube of size n. In order to limit the increase of the accumulation of these differences, this paper proposes a method that limits the accumulation of the difference by redistributing an unit load (odd or even) of the same type, if possible, when there is a load distribution between two processors. We reduced the maximum difference to LCEIL logn over {2} RCEIL . The result shows the simulation experiments which show about 30% improvement in speedup compare to the DEM.

• Journal of Internet Computing and Services
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• v.5 no.6
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• pp.93-101
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• 2004

In a receiver-initiated load redistribution algorithm, receiver(underloaded processor) continues to send unnecessary request messages for load transfer until a sender(overloaded processor) is found while the system load is light, Therefore, it yields many problems such as low cpu utilization and system throughput because of inefficient inter-processor communications until the receiver receives an accept message from the sender in this environment. This paper presents an approach based on genetic algorithm(GA) for dynamic load redistribution in heterogeneous distributed systems. In this scheme the processors to which the requests are sent off are determined by the proposed GA to decrease unnecessary request messages. The performance of proposed algorithm shows better than that of the conventional algorithm through various experiments.

• Korean Journal of Social Welfare
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• v.5
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• pp.111-138
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• 1984

• The Korean Journal of Financial Management
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• v.4 no.1
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• pp.59-80
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• 1988

• 한국사회복지학회:학술대회논문집
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• 1994.11a
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• pp.205-213
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• 1994

• Magazine of the Korea Concrete Institute
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• v.19 no.4
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• pp.20-24
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• 2007