• Proceedings of the KSME Conference
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• 2000.04b
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• pp.51-56
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• 2000

The Finite Element Solutions Is reported on solid-liquid phase change in porous media with natural convection including freezing. The model is based on volume averaged transport equations, while phase change is assumed to occur over a small temperature range. The FEM (Finite Element Method) algorithm used in this study is 3-step time-splitting method which requires much less execution time and computer storage the velocity-pressure integrated method and the penalty method. And the explicit Lax-Wendroff scheme is applied to nonlinear convective term in the energy equation. For natural convection including melting and solidification the numerical results show reasonable agreement with FDM (Finite Difference Method) results.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.484-484
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• 2000

The problem of determining the proper size of an neural network is recognized to be crucial, especially for its practical implications in such important issues as learning and generalization. Unfortunately, it usually is not obvious what size is best: a system that is too snail will not be able to learn the data while one that is just big enough may learn the slowly and be very sensitive to initial conditions and learning parameters. One popular technique is commonly known as pruning and consists of training a larger than necessary network and then removing unnecessary weights/nodes. In this paper, a new pruning method is developed, based on the penalty-term methods. This method makes the neural network good for the generalization and reduces the retraining time after pruning weights/nodes.

• Journal of the Korea Safety Management & Science
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• v.1 no.1
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• pp.19-28
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• 1999

This paper presents the safety management model, which is appropriate for small-to-medium enterprises that rank the highest disaster rate. It is required for these companies to modify and improve the safety-related articles and it is peformed to compare and analyze the industrial disasters and safety management systems between large enterprises and small-to-medium enterprises. The basic direction of change of industrial safety healthy system must be classified to the dual direction. For large enterprises, it is focused on not pre-regulations but post-regulations based on the self-control safety management system. But for small-to-medium enterprises, it is required to intensify the safety management system and the safety responsibility for owners or administrators. Specially, the responsibility for disaster must be more strengthened by the penalty and the insurance method, and then it must be performed not only the financial support of government but also middle and long-term technical support by private safety organizations.

• Proceedings of the Safety Management and Science Conference
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• 1999.11a
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• pp.73-82
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• 1999

This paper presents the safety management model, which is appropriate for small-to-medium enterprises that rank the highest disaster rate. It is required for these companies to modify and improve the safety-related articles and it is performed to compare and analyze the industrial disasters and safety management systems between large enterprises and small-to-medium enterprises. The basic direction of change of industrial safety healthy system must be classified to the dual direction. For large enterprises, it is focused on not pre-regulations but post-regulations based on the self-control safety management system. But for small-to-medium enterprises, it is required to intensify the safety management system and the safety responsibility for owners or administrators. Specially, the responsibility for disaster must be more strengthened by the penalty and the insurance method, and then it must be performed not only the financial support of government but also middle and long-term technical support by private safety organizations.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.42.3-42
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• 2001

A human is an expert in manipulation. We have acquired skills to perform dexterous operations based upon knowledge and experience attained over a long period of time. It is important in robotics to understand these human skills, and utilize them to bring about better robot control and operation It is hoped that the neurocontroller can be trained and organized by simply presenting human teaching data, which implicate human intention, strategy and expertise. In designing a neurocontroller, we must determine the size of neurocontroller. Improper size may not only incur difficulties in training neural nets, e.g. no convergence, but also cause instability and erratic behavior in machines. Therefore, it is necessary to determine the proper size of neurocontroller for human control transfer. In this paper, a new pruning method is developed, based on the penalty-term methods. This method makes ...

• Communications for Statistical Applications and Methods
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• v.30 no.2
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• pp.149-162
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• 2023

The ℓ₁-trend filtering method is one of the most widely used methods for extracting underlying trends from noisy observations. Contrary to the Hodrick-Prescott filtering, the ℓ₁-trend filtering gives piecewise linear trends. One of the advantages of the ℓ₁-trend filtering is that it can be used for identifying change points in piecewise linear trends. However, since the ℓ₁-trend filtering employs total variation as a penalty term, estimated piecewise linear trends tend to be biased. In this study, we demonstrate the biasedness of the ℓ₁-trend filtering in trend level estimation and propose a two-stage bias-reduction procedure. The newly suggested estimator is based on the estimated change points of the ℓ₁-trend filtering. Numerical examples illustrate that the proposed method yields less biased estimates for piecewise linear trends.

• Korean Journal of Construction Engineering and Management
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• v.17 no.1
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• pp.119-127
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• 2016

Since May 23, 2014, the Construction Technology Promotion Act has been effect through the entire reform of the Act. Despite the extensive reform, the previous penalty articles remain intact. According to the article 85 (1), especially, if a service provider or an engineer has caused death or injury by violating the duty of good faith and by damaging the principal parts of facilities, the person should be sentenced for lifetime imprisonment or imprisonment for no less than three years. The article has been controversial in its clarity and adequacy. This study is to verify the characteristics and the scope of the article and to suggest the theoretical backgrounds by analyzing the article based on the principle of legality, which enables to set forth the possibility to improve the article. To achieve the goal, the provision has been analyzed in accordance with the basic laws in Korea including the constitutional law and the criminal law, the related cases have been collected, and the comparison of the relevant acts has been executed. The detailed discussion about the articles in laws and acts on construction and the long-term and integrated study are expected to vitalize through this research.

• The Plant Pathology Journal
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• v.31 no.3
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• pp.305-309
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• 2015

After four years of cold storage, dimethachlon resistance of two laboratory-induced resistant Sclerotinia sclerotiorum isolates SCG7 and LA50 declined by 99.5% and 98.9%, respectively, and cross resistance to iprodione and procymidone also declined dramatically. Along with the decline of fungicide resistance, osmotic sensitivity to sodium chloride and glucose decreased tremendously; mycelial growth rate, sclerotia number and weight per potato dextrose agar (PDA) plate increased on average by 118.6%, 85. 5% and 64.5%, respectively; and virulence to detached leaves of oilseed rape increased by 72.7% on average. Significant negative correlations were detected between dimethachlon resistance levels and mycelial growth rate on PDA (r = -0.980, P = 0.021), and between resistance levels and lesion diameters on detached leaves of oilseed rape plants (r = -0.997, P = 0.002). These results have profound implications for assessing the potential risk for resistance development to dicarboximide fungicides in S. sclerotiorum.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.1
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• pp.112-123
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• 1997

The optimization techniques have been applied to versatile engineering problems for reducing manufacturing cost and for automatic design. The deterministic approaches or op5imization neglect the effects on uncertainties of design variables. The uncertainties include variation or perturbation such as tolerance band. The optimum may be useless when the constraints considering worst cases of design variables can not be satisfied, which results from constraint variation. The variation of design variables can also give rise to drastic change of performances. The two issues are related to constraint feasibility and insensitive performance. Robust design suggested in the present study is developed to gain an optimum insensitive to variation on design variables within feasible region. The multiobjective function is composed to the mean and the standard deviation of original objective function, while the constraints are supplemented by adding penalty term to original constraints. This method has a advantage that the second derivatives of the constraints are not required. A mathematical problem and several standard problems for structural optimization are solved to check out the usefulness of the suggested method.

• Journal of the Society of Naval Architects of Korea
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• v.51 no.6
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• pp.480-488
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• 2014

Vortex shedding which is the dominant feature of body wakes and of direct relevance to practical engineering problems, has been intensively studied for flows past a circular cylinder. In contrast, vortex shedding from a hydrofoil trailing edge has been studied to much less extent despite numerous practical applications. The physics of the problem is still poorly understood. The present study deals with $K{\acute{a}}rm{\acute{a}}n$ vortex shedding from a truncated trailing-edge hydrofoil in relatively high Reynolds number flows. The objectives of this paper are twofold. First, we aim to simulate unsteady turbulent flows past a two dimensional hydrofoil through a hybrid particle-mesh method and penalization method. The vortex-in-cell (VIC) method offers a highly efficient particle-mesh algorithm that combines Lagrangian and Eulerian schemes, and the penalization method enables to enforce body boundary conditions by adding a penalty term to the momentum equation. The second purpose is to investigate shedding frequencies of vortices behind a NACA 0009 hydrofoil operating at a zero angle of attack.