• Nuclear Engineering and Technology
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• v.53 no.7
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• pp.2084-2094
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• 2021

Delta-form-based methods for solving high order spatial discretization schemes are introduced into the reactor S_N transport equation. Due to the nature of the delta-form, the final numerical accuracy only depends on the residuals on the right side of the discrete equations and have nothing to do with the parts on the left side. Therefore, various high order spatial discretization methods can be easily adopted for only the transport term on the right side of the discrete equations. Then the simplest step or other robust schemes can be adopted to discretize the increment on the left hand side to ensure the good iterative convergence. The delta-form framework makes the sweeping and iterative strategies of various high order spatial discretization methods be completely the same with those of the traditional S_N codes, only by adding the residuals into the source terms. In this paper, the flux limiter method and weighted essentially non-oscillatory scheme are used for the verification purpose to only show the advantages of the introduction of delta-form-based solving methods and other high order spatial discretization methods can be also easily extended to solve the S_N transport equations. Numerical solutions indicate the correctness and effectiveness of delta-form-based solving method.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.2 s.308
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• pp.87-92
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• 2006

In array signal processing, high order statistics can be used to estimate parameters from signal of sums of complex exponential. This paper presents a high order Matrix Pencil method(MPM) using the fourth order cumulant. Since the fourth order cumulant can suppress the Gaussian noise, the response of MPM has better noise immunity than the conventional approaches. We successfully formulate the high order MPM with all the benefits of MPM along with higher accuracy. In the numerical simulations we demonstrated that the proposed method with forth order cumulant has better resolution to find degree of arrival(DOA) in the presence of the Gaussian noise.

• Journal of electromagnetic engineering and science
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• v.11 no.1
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• pp.11-15
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• 2011

Preserving high-order accuracy in high-order FDTD solutions across dielectric interfaces is very important for practical time-domain electromagnetic simulations. This paper presents a fourth-order accurate numerical boundary scheme for the planar dielectric interface to be used in the fourth-order FDTD method proposed earlier by the author. The interface scheme for the two-dimensional (2-D) transverse magnetic (TM) polarization case is derived and validated by monitoring the $L_2$ norm errors in the numerical solutions of a partially-filled cavity demonstrating its fourth-order convergence and long-time numerical stability in the presence of the planar dielectric interface.

• Journal of computational fluids engineering
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• v.12 no.3
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• pp.29-40
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• 2007

An implicit discontinuous Galerkin method for the two-dimensional Euler equations was developed on unstructured triangular meshes. The method can achieve high-order spatial accuracy by using hierachical basis functions based on Legendre polynomials. Numerical tests were conducted to estimate the convergence order of numerical solutions to the Ringleb flow and the supersonic vortex flow for which analytic solutions are available. Also, the flows around a 2-D circular cylinder and an NACA0012 airfoil were numerically simulated. The numerical results showed that the implicit discontinuous Galerkin methods couples with a high-order representation of curved solid boundaries can be an efficient method to obtain very accurate numerical solutions on unstructured meshes.

• Bulletin of the Korean Mathematical Society
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• v.55 no.1
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• pp.297-310
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• 2018

In this paper, a nonlinear high-order difference scheme is proposed to solve the Extended-Fisher-Kolmogorov equation. The existence, uniqueness of difference solution and priori estimates are obtained. Furthermore, the convergence of the difference scheme is proved by utilizing the energy method to be of fourth-order in space and second-order in time in the discrete $L^{\infty}-norm$. Some numerical examples are given in order to validate the theoretical results.

• Structural Engineering and Mechanics
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• v.34 no.6
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• pp.779-799
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• 2010

In order to consider high-order effects on the actual limit state function, a new response surface method is proposed for structural reliability analysis by the use of high-order approximation concept in this study. Hermite polynomials are used to determine the highest orders of input random variables, and the sampling points for the determination of highest orders are located on Gaussian points of Gauss-Hermite integration. The cross terms between two random variables, only in case that their corresponding percent contributions to the total variation of limit state function are significant, will be added to the response surface function to improve the approximation accuracy. As a result, significant reduction in computational cost is achieved with this strategy. Due to the addition of cross terms, the additional sampling points, laid on two-dimensional Gaussian points off axis on the plane of two significant variables, are required to determine the coefficients of the approximated limit state function. All available sampling points are employed to construct the final response surface function. Then, Monte Carlo Simulation is carried out on the final approximation response surface function to estimate the failure probability. Due to the use of high order polynomial, the proposed method is more accurate than the traditional second-order or linear response surface method. It also provides much more efficient solutions than the available high-order response surface method with less loss in accuracy. The efficiency and the accuracy of the proposed method compared with those of various response surface methods available are illustrated by five numerical examples.

• Journal of Veterinary Clinics
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• v.9 no.2
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• pp.433-449
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• 1992

Total CPK activities and CPK isoenzymes fractions of the sera and tissues were examined to obtain the physiological basic data of ruminant available in veterinary clinical practice. For the sera total CPK activities and CPK isoenzymes fractions, total 39 clinically healthy Korean native goats (3 to 10 months old, IS of female and 18 of male) and 6 of Korean native goats (1 to 2 years old, 3 of female and 3 of male) were used. Seventeen Korean native cattle (3 to 6 years old, 10 of female and 7 of male) and 27 Holstein-Friesian cattle (2 to 8 months old, 7 of female and 3 to 12 years old, 20 of female) were also examined for the sera total CPK activities and CPK isoenzymes fractions. For the total CPK activities and CPK isoenzyme fractions, 3 of female Korean native goats (7 months old), 3 of female Korean native cattle (2 years old) and 3 of dairy cattle (2 years old, 2 of female and 1 of male) were used. The tissues examined were the cerebrum (2 of Korean native cattle), spinal cord (1 of Korean native cattle), heart, lung, diaphragm, reticulum, liver, spleen, kidney, jejunum. colon and femoral muscle. The results obtained were as follows : 1. In Korean native goats less than 1-year-old. serum total CPK activities were 67.8${\pm}$17.7(39.0~96.5) IU/$\ell$ in female and 63.4${\pm}$19.0(28.7~94.4) IU/$\ell$ in male. Further they were 67.0${\pm}$5.3(59.5~70.7) IU/$\ell$ and 54.5${\pm}$11.1(39.1~69.4) IU/$\ell$ in female and male Korean native goats over 1-year-old, respectively. Serum total CPK activities of female were slightly higher than those of male. Significance between age and sex was not found. 2. Serum total CPK activities were 56.8${\pm}$19.7(27.6~90.5) IU/$\ell$ and 65.6${\pm}$10.8(52.8~78.0) IU/$\ell$ in female and male Korean native adult cattle, respectively, Serum total CPK activities of male were slightly higher than those of female, but they were not significant 3. Serum total CPK activities we,e 72.5${\pm}$8.2(57.2~83.2) IU/$\ell$ and 60.8${\pm}$12.5(42.7~80.6) IU/$\ell$ in calves and adult of dairy acttle, respectively. Serum total CPK activities of calves were significantly higher than those of adult(p<0.05). 4. In Korean native goats less than 1-year-old, serum CPK isoenzymes fractions were high with decreasing order of MM>MB>BB and MM>BB>MB in female and male, respectively. Further they were high with decreasing order of MM>MB>BB and MM>B8>MB in female and male Korean native goats over 1-year-old, respectively. The main fractions of CPK isoenzymes were MM in sera of Korean native goats. 5. Serum CPK Isoenzyme fractions were high with decreasing order of MM>MB>BB In both female and male of Korean native cattle. The main fraction among them was MM. 6. Serum CPK isoenzymes fractions were high with decreasing order of MM>BB>MB in both calves and adult of dairy cattle. The main fraction among them was MM. 7. Total CPK activities were high with decreasing order of the femoral muscle>kidney>reticulum>diaphragm>liver>spleen>heart>colon>lung>jejunum in Korean native goats. 8. Total CPK activities were high with decreasing order of the spinal cord >cerebrum>femoral muscle>reticulum>kidney>liver>spleen>diaphragm>lung>colon>heart>jejunum in Korean native cattle. 9. Total CPK activities were high with decreasing order. of the femoral muscle >liver>retoculum>kidney>heart>colon>lung>spleen>jejunum>diaphrasm in dairy cattle. 10. The pattern of the cardiac CPK isoenzymes fractions was identical in Korean native goats, Korean native cattle and dairy cattle. They were high in the order of MM>MB without BB fractions and the main fraction was MM. 11. The pattern of the pulmonary CPK isoenzymes fractions was the same Korean native goats, Korean native cattle and dairy cattle. They were high with decreasing order of MM>MB>BB and the main fraction among them was MM. 12. The pattern of CPK isoenzymes fractions of the diaphragm was Identical in Korean native goats and Korean native cattle. They were high with decreasing order of MM >BB >MB except dairy cattle (MM>MB>BB) but the main fraction among them was MM. 13. The pattern of the reticular CPK isoenzymes fractions was identical in Korean native cattle and dairy cattle. They were high with decreasing order of BB >MM >MB except Korean native goats(BB>MB>MM) but the main, fraction among them was BB 14. The pattern of the hepatic CPK isoenzymrs fractions was identical in Korean native cattle and dairy cattle. They were high with decreasing order of MB >BB >MM except Korean native goats(MB>MM>BB)but the main fraction was MB. 15. The splenic CPK isoenzymes fractions showed different pattern. They were high with decreasing order of MB>BB>MM, MM>BB>MB and BB>MB>MM in Korean native goats, Korean native cattle and dairy cattle, respectively. The main fraction among them was different from each other. 16. The pattern of the renal CPK isoenzymes fractions was identical in Korean native cattle and dairy cattle. They were high with decreasing order of MM >MB>BB except Korean native goats(BB>MB>MM). 17. The CPK isoenzymes fractions of the Jejunums showed different pattern. They were high with decreasing order MM>MB>BB, MM>BB>MB and BB>MM>MB in Korean native goats, Korean native cattle and dairy cattle, respectively. The main fractions were MM In Korean native goats and Korean native cattle, and BB in dairy cattle. 18. The colonic CPK isoenzymes fractions showed different pattern. They were high with decreasing order of MM>MB>BB, MM>BB>MB and BB>rrfB>MM in Korean native goats, Korean native cattle and dairy cattle, respectively. The main fractions were MM in Korean native goats and Korean . native cattle, and BB in dairy cattle. 19. The cerebral CPK isoenzymes fractions were high with decreasing order of BB >MM without MB detected in Korean native cattle and those of spinal cord were high with decreasing order of BB >MM >MB. The main fractions in both cerebrum and spinal cord were BB.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.9
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• pp.1276-1282
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• 2013

This paper presents a demosaicking method based on high-order interpolation with parameters. Demosaicking is an essential process in capturing color images through a single sensor-array. Thus, a lot of methods including the Hamilton-Adams(HA) method has been studied in this literature. However, the image quality depends on various factors such as contrast and correlation in color space; existing algorithms depend on test images in use. Consequently, a new test image set was suggested to develop demosaicking algorithms properly. According to previous studies, the HA method shows high performances with the new test data set. In this paper, we improve the HA method using high-order interpolation with parameters. Also, we provide an analysis and formulations for the proposed method. To evaluate our method, we compare our method with the existing methods both objectively and subjectively. The experimental results indicate that the proposed method is superior to the existing methods.

• Proceedings of the IEEK Conference
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• 2002.07b
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• pp.856-859
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• 2002

This paper proposes a high-performance VLSl architecture using distributed arithmetic for higher-order FIR filters with complex coefficients. For the purpose of realizing high sampling rate with small latency in high-order filters, we apply distributed arithmetic[1］. Moreover, in order to decrease drastically the power dissipation, the structure applying not ROM's but optimum function circuits which we have previously proposed, is utilized［2]［3］. However, this structure increases in the number of adders as compared to the conventional structure applying ROM's. In order to realize a more effective method for further higher-order filter, we propose newly an implementation applying two methods which have large effects on the unit using the adders. First , we propose an implementation applying SFAs(Serial Full Adders) and SFSs(Serial Full Subtractors). Second, we propose a structure applying proposed 4-2 adders. Finally, it is shown that the proposed architecture is an effective way to realize low power dissipation and small latency while the sampling rate is kept constant for further higher-order filters with complex coefficients.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.253-256
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• 1996

In this paper, A new time-varying sliding surface design using eigenvalue locus is proposed to achieve fast and robust in a class of high-order uncertain dynamic system. A moving sliding surface(MSS) was proposed earlier for the second-order variable structure control systems(VSCS). This methodology led to fast and robust control responses of the second-order VSCS. However, the moving algorithm of the MSS was too complicated to be employed the high-order VSCS. To resolve this problem, we propose a new moving algorithm that switching surface moves such that the eigenvalues of equivalent system in the sliding mode have a predetermined locus. Using the proposed surface fast and robust behaviors are accomplished. The problem of chattering can be eliminated by using a boundary layer of switching surface. The efficiency of proposed algorithm is illustrated by an application to four-order workbench.