• Proceedings of the Korean Magnestics Society Conference
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• 2014.05a
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• pp.127-127
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• 2014

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.18 no.4
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• pp.294-300
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• 2006

Implicit numerical scheme using fractional step method and FCT is used to improve the computational efficiency of WAM. Square wave test and simulation of typhoon generated waves are conducted to verify the numerical scheme. The applied scheme shows much less numerical diffusion and due to the implicit character of the scheme much larger time steps can be used without numerical instability. For typhoon MAEMI, comparison between the numerical results and the measured data shows good agreement.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.5
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• pp.8-14
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• 2009

Corrugated fiberboard is a widely used packaging material because of its high compressive strength and stiffness despite light weight. Corrugated fiberboards with microflutes with height $\leq$ 1.5 mm, such as E, F or G, have been developed. As microflutes have a different geometry from other conventional flutes, they may behave differently in testing and require a new testing method. Therefore, we evaluated the flat crush resistance of corrugated fiberboard with microflutes according to the ISO and TAPPI standard test methods. In addition, the effects of specimen area and platen compression rate were examined. The goal of this study was to identify an appropriate method for flat crush test (FCT) of corrugated fiberboard with microflutes. When a test piece with a standard area was subjected to the FCT in accordance with ISO and TAPPI methods, microflute corrugated fiberboard demonstrated a different load-displacement curve. An area of 20 $cm^2$ was determined to be the most appropriate for FCTof microflute corrugated fiberboard.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.4
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• pp.325-331
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• 2007

In this study, the inter-metal dielectric material of FSG was changed by low-k material in $0.13{\mu}m$ foundry-compatible technology (FCT) device process based on fluorinated silicate glass (FSG). Black diamond (BD) was used as a low-k material with a dielectric constant of 2.95 for optimization and yield-improvement of the low-k based device process. For yield-improvement in low-k based device process, some problems such as photoresist (PR) poisoning, damage of low-k in etch/ash/cleaning process, and chemical mechanical planarization (CMP) delamination must be solved. The PR poisoning was not observed in BD based device. The pressure in CMP process decreased to 2.8 psi to remove the CMP delamination for Cu-CMP and USG-CMP. $H_2O$ ashing process was selected instead of $O_2$ ashing process due to the lowest condition of low-k damage. NE14 cleaning after ashing process lot the removal of organic residues in vias and trenches was employed for wet process instead of dilute HF (DHF) process. The similar-state of SRAM yield was obtained in Cu/low-k process compared with the conventional $0.13{\mu}m$ FCT device by the optimization of these process conditions.

• Journal of Ginseng Research
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• v.37 no.4
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• pp.491-495
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• 2013

Wood-cultivated ginseng, including roots in its dried form, is produced in forest land without using artificial facilities such as light barriers. To identify suitable sites for the propagation of wood-cultivated ginseng, factor combination technique (FCT) and linear combination technique (LCT) were used with geographic information system and the results were superimposed onto an actual wood-cultivated ginseng plantation. The LCT more extensively searched for suitable sites of cultivation than that by the FCT; further, the LCT probed wide areas considering the predominance of precipitous mountains in Korea. In addition, the LCT showed the much higher degree of overlap with the actual cultivation sites; therefore, the LCT more comprehensively reflects the cultivator's intention for site selection. On the other hand, the inclusion of additional factors for the selection of suitable cultivation sites and experts' opinions may enhance the effectiveness and accuracy of the LCT for site application.

• Journal of computational fluids engineering
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• v.3 no.1
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• pp.1-10
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• 1998

서로 섞이지 않는 두 비압축성 유체의 유동을 해석하기 위하여 VOF 방법에 기초한 수치 기법을 개발하였다. 유체간의 계면형상의 거동은 유동장내의 유체의 점유체적비의 변화에 의해 묘사되는데 이를 지배하는 이동방정식을 풀기 위한 새로운 대류항 계산법을 고안하였다. 대류항은 유체계면의 방향에 따라 풍상법과 역풍상법의 적절한 조합을 취하여 계산하는데 여기에 대각방향의 상류효과를 포함시켜 시간에 대한 2차 정확도를 갖도록 하였다. 또한 이 방법을 유량보정수송(FCT)법과 결합시켜 해의 단조성을 보장하였다. 몇 가지 단순 문제에 대한 시험 결과 이 기법이 수치오차에 의한 계면형상의 변형과 파손을 감소시킴을 확인하였다.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.10
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• pp.61-70
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• 1996

In this paper, we find the values of near-end crosstalk coefficient in striplines of a FR-4 multilayer PCB by an analytic method and a HSPICE simulation method, and define calcualtion errors in an analytic method and define the application range, and simualte near-end crosstalk coefficients of the FCT (fast CMOS TTL) in complicated striplines by HSPICE and analyze near-en crosstalk coefficients in relation to dielectric thickness and trace spaces of striplines. As a result, we analyze coupling structure of the near-end crosstalk in the coplicated sstriplines that are impedance matched and define a coupling formula of near-end crosstalk coefficients in general complicated striplines. Especially, it is approximated in the layout grade rule.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.253-254
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• 1996

To understand the dynamical structures of stellar wind bubble, one and two-dimensional calculations has been performed. Using FCT Code with cooling effects and assuming constant mass loss rate and ambient medium density, we could divide stellar winds into the regime of slow and fast winds. The slow wind driven bubble shows initially radiative and becomes partially radiative bubble in which shocked stellar wind zone is still adiabatic. In contrast., the fast wind driven bubble shows initially fully adiabatic and becomes adiabatic bubbles with radiative outer shell. We also determine analytically the onset of thin-shell formation time in case of fast wind driven bubble with power-law energy injection and ambient density structure. We solve the line transfer problem with numerical results in order to calculate line profile of [OIII] forbidden line.

• 한국전산유체공학회:학술대회논문집
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• 1995.10a
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• pp.182-187
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• 1995

The present paper explains some advancement made by the authors for the compressible flow computation of the Euler equations based on the unstructured grid and vertex- centered finite volume method. Accurate solutions to the unsteady axisymmetric shock wave propagation problems and three-dimensional airplane flows have been obtained by a high-order upwind TVD and FCT schemes. Unstructured grid adaption is made for the unsteady shock wave problems by the dynamic h-refinement/unrefinement procedure and for the three-dimensional steady flows by the Delaunay point-insertion method to generate three-dimensional tetrahedral mesh enrichment. Some physics of the shock wave diffraction phenomena and three-dimensional airplane flow are discussed.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.5
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• pp.157-161
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• 2007

There are technological changes to reduce the size and weight of electronic components and to accommodate multi-functions in them. To meet this trend, more complicated technological processes are required. To maintain the processes, more accurate inspection systems are also necessary. Therefore, new inspection methods are needed, which is differ from conventional inspection methods such as electrical test methods ICT(In-Circuit Test), FCT(Function Test) and visual test using optical equipments. One of the possible approaches is non-destructive test using X-ray. In this paper, an inspection method using X-ray is developed and applied to inspection of soldering state and internal defects of electronic components.