• Journal of the Korea Society of Computer and Information
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• v.28 no.11
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• pp.1-11
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• 2023

Breast cancer is the disease that affects women the most worldwide. Due to the development of computer technology, the efficiency of machine learning has increased, and thus plays an important role in cancer detection and diagnosis. Deep learning is a field of machine learning technology based on an artificial neural network, and its performance has been rapidly improved in recent years, and its application range is expanding. In this paper, we propose a DNN-SVM hybrid model that combines the structure of a deep neural network (DNN) based on transfer learning and a support vector machine (SVM) for breast cancer classification. The transfer learning-based proposed model is effective for small training data, has a fast learning speed, and can improve model performance by combining all the advantages of a single model, that is, DNN and SVM. To evaluate the performance of the proposed DNN-SVM Hybrid model, the performance test results with WOBC and WDBC breast cancer data provided by the UCI machine learning repository showed that the proposed model is superior to single models such as logistic regression, DNN, and SVM, and ensemble models such as random forest in various performance measures.

• The KSFM Journal of Fluid Machinery
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• v.13 no.5
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• pp.43-53
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• 2010

This study investigates a design optimization of a rotating two-pass rectangular cooling channel with staggered arrays of pin-fins. The radial basis neural network method is used as an optimization technique with Reynolds-averaged Navier-Stokes analysis of fluid flow and heat transfer with shear stress transport turbulent model. The ratio of the diameter to height of the pin-fins and the ratio of the streamwise spacing between the pin-fins to height of the pin-fin are selected as design variables. The optimization problem has been defined as a minimization of the objective function, which is defined as a linear combination of heat transfer related term and friction loss related term with a weighting factor. Results are presented for streamlines, velocity vector fields, and contours of Nusselt numbers, friction coefficients, and turbulent kinetic energy. These results show how fluid flow in a two-pass square cooling channel evolves a converted secondary flows due to Coriolis force, staggered arrays of pin-fins, and a $180^{\circ}$ turn region. These results describe how the fluid flow affects surface heat transfer. The Coriolis force induces heat transfer discrepancy between leading and trailing surfaces, having higher Nusselt number on the leading surface in the second pass while having lower Nusselt number on the trailing surface. Dean vortices generated in $180^{\circ}$ turn region augment heat transfer in the turning region and in the upstream region of the second pass. As the result of optimization, in comparison with the reference geometry, thermal performance of the optimum geometry shows the improvement by 30.5%. Through the optimization, the diameter of pin-fin increased by 14.9% and the streamwise distance between pin-fins increased by 32.1%. And, the value of objective function decreased by 18.1%.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.12
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• pp.201-208
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• 2000

A numerical analysis algorithm for thermally loaded structures has been proposed and compared with the general free vibration approach to determine the characteristics of thermal load effects in vibration structures. The field of numerical inspection includes free vibration analysis, transient heat transfer analysis and thermal stress analysis. The key point of the analysis of thermally loaded structure is the method of parallel time integration between transient heat transfer and free vibration simultaneously. The results of the study demonstrate the computation of the specific total external force vector and stiffness matrix. The proposed analysis method can be applied to both heated and cooled structure vibration analysis.

• Journal of electromagnetic engineering and science
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• v.5 no.4
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• pp.183-188
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• 2005

A simple microwave backscattering model for vegetation canopies on earth surfaces is developed in this study. A natural earth surface is modeled as a two-layer structure comprising a vegetation layer and a ground layer. This scattering model includes various scattering mechanisms up to the first-order multiple scattering( double-bounce scattering). Radar backscatter from ground surface has been modeled by the polarimetric semi-empirical model (PSEM), while the backscatter from the vegetation layer modeled by the vector radiative transfer model. The vegetation layer is modeled by random distribution of mixed scattering particles, such as leaves, branches and trunks. The number of input parameters has been minimized to simplify the scattering model. The computation results are compared with the experimental measurements, which were obtained by ground-based scatterometers and NASA/JPL air-borne synthetic aperture radar(SAR) system. It was found that the scattering model agrees well with the experimental data, even though the model used only ten input parameters.

• Journal of Mechanical Science and Technology
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• v.18 no.4
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• pp.718-730
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• 2004

The solution for the natural convection in internally finned horizontal annuli is obtained by using a numerical simulation of time-dependent and two-dimensional governing equations. The fins existing in annuli influence the flow pattern, temperature distribution and heat transfer rate. The variations of the On configuration suppress or accelerate the free convective effects compared to those of the smooth tubes. The effects of fin configuration, number of fins and ratio of annulus gap width to the inner cylinder radius on the fluid flow and heat transfer in annuli are demonstrated by the distribution of the velocity vector, isotherms and streamlines. The governing equations are solved efficiently by using a parallel implementation. The technique is adopted for reduction of the computation cost. The parallelization is performed with the domain decomposition technique and message passing between sub-domains on the basis of the MPI library. The results from parallel computation reveal in consistency with those of the sequential program. Moreover, the speed-up ratio shows linearity with the number of processor.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.27 no.1
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• pp.51-56
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• 2017

This paper presents an approach of predicting the radiated noise due to the structural vibration by internal harmonic forces using the doubly asymptotic approximation (DAA). Acoustic transfer vector is derived from the Helmholtz integral equation and the fluid-structure interaction relation of DAA. Numerical results and analytical results of radiated noise for a cylindrical shell were compared and showed that they were consistent in most of frequencies and radiation directions, but showed errors in some radiated directions in the mid-frequency region. Despite these errors, the prediction method will be suitable for practical radiated noise prediction.

• Journal of the Korean Vacuum Society
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• v.8 no.3B
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• pp.368-375
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• 1999

The Maxwell equation and the transformer equivalent-circuit model are applied to a radio frequency planar inductively coupled plasma. The spatial distribution of the vector potential, the magnetic field, and the electric field are obtained analytically. As a result, the plasma current, the mutual inductance between the coil and the plasma, and the self inductance of plasma are found to increase with increasing skin depth. The spatial distribution of absorbed power has maximum where the antenna coil exists, and has a similar profile to that of the induced electric field. The power transfer efficiency is found to increase with increasing gas pressure before a saturation around p+ 20mTorr, while it shows an increase with the plasma density before a slight decrease around a density of $5\times10^{11}/\textrm{cm}^3$.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2005.10a
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• pp.145-145
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• 2005

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.4
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• pp.777-783
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• 2007

In this paper, we present a novel control approach for linear motor-based transfer systems in which friction reduction and enhancement of control performance are considered. In general, in such systems friction effects from rails and wheels, and internal bearings complicate control scheme since in particularly its dynamics are arbitrarily changed due to mass variation, detent force of motor systems, and gaps among stators. Our control approach is achieved to reduce this undesired friction dynamics using fuzzy system. We construct hybrid control approach for this control system which Is composed of a nominal control and a vertical control against friction. Fuzzy parameter vector is optimally determined from iterative simulation experiments. We demonstrate its superiority via numerical simulations comparing with a traditional control method.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.3
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• pp.427-434
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• 1994

The primordial germ cells (PGCs) were transfected in vitro and expressed the exogenous RSVLTR/${\beta}G2$ plasmid, suggesting thaI PGC is a possible vector for direct gene transfer into the germ line. Transfection efficiency of cell suspensions containing PGCs was 1.5% by liposome mediated DNA transfection. By microinjection of the transfected PGCs into the host germinal crescent, PGCs migrated via blood vessel to the future gonad and these transfected PGCs resulted in the RSVLTR/${\beta}G2$ expression in the gonad. The results from the seeding of PGCs on the chorioallantoic membrane were insufficient to test the hypothesis that PGCs can penetrate or invade the chorioallantoic membrane for transport via the circulatory system.