• 한국구조물진단유지관리공학회 논문집
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• 제6권3호
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• pp.97-102
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• 2002

Two dimensional Analysis has been applied to most of tunnel lining design in these days. Two dimensional analysis uses beam or curved beam element for finite element method. But because the behaviors of tunnel concrete lining structure is near to shell, it is required to model the tunnel lining as shell structure for safety design of tunnel lining structure. In this paper, two dimensional analysis by beam element and the three dimensional analysis by shell element of tunnel concrete lining are studied, in which 3 type of tunnel lining and lateral pressure factors are considered. As results of the study, three dimensional analyses of the behavior of tunnel concrete lining structure considering lateral pressure factor shows that the moment of three dimensional analysis is greater than those of two dimensional analysis. The results shows that three dimensional analysis is necessary for safety design of tunnel lining.

• 대한기계학회논문집B
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• 제25권1호
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• pp.1-8
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• 2001

Performance of a rectangular fin is investigated by a three dimensional analytical method. Heat loss and the temperature obtained from the three dimensional analysis are compared with those calculated from a two dimensional analysis. Fin effectiveness, fin resistance and fin efficiency for the rectangular fin are presented as a function of non-dimensional fin length and fin width. The results are obtained in the following : (1) heat loss calculated from the two dimensional analysis is the same as that obtained from the three dimensional analysis with adiabatic boundary condition in z-direction, (2) heat loss obtained from the two dimensional analysis approaches the value for the three dimensional analysis as the non-dimensional fin width becomes large, (3) fin effectiveness increases as non-dimensional fin length increases and non-dimensional fin width decreases, and vice versa for fin efficiency.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2008년도 학술발표회 논문집
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• pp.1732-1736
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• 2008

The characteristics of a river flow analysis are significant for river maintenance plan. At the present time, HEC-RAS, 1-Dimensional Numerical Analysis Model, is mainly applied to analyze the character of a river flow. The shape of a river is somewhat in longitudinal linear form. It was suspected that the usage of 1-dimensional numerical analysis model is more economical. Development of numerical analysis models and computers are possible to calculate large volume. Hence, it is possible to adapt the analysis of the key stations by 2-dimensional numerical analysis model. The limitation of 1-Dimensional Numerical Analysis Model is that it is hard to evaluate structure affection of numerical simulation by energy loss coefficient at river structure analyzing. When adaptation of the 2-dimensional numerical analysis model in river structure ensues, it takes more objective analyzing than 1-dimensional numerical analysis model for flow affection by river structure. 2-dimensional numerical analysis model consults with the different structure position of hydraulic characteristics and different water depth of shape and scope in vertical flow. 1-dimensional numerical analysis model is possible to simulate with only energy loss coefficient for sudden river section changing, sudden waterway changing by curved. 2-dimensional numerical analysis model use original geographical features. So the model removes technical subjectivity of faulty judgment. It is an objective analysis.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제51권10호
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• pp.545-553
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• 2002

This paper is about the analysis of 3-dimensional magnetic field distribution in CPM(Convergence Purity Magnet) considering magnetization vector and the optimum design of CPM. The magnetization vector of CPM is obtained using 2-dimensional magnetization FEA(Finite Element Analysis) coupled with Priesach model. Using this magnetization vector of CPM, we analysed the 2-dimensional and 3-dimensional magnetostatic field of CPM and know that these analysis results are not equal. From experimental result, we know that the 3-dimensional analysis is accurate because the magnetic field distribution in CPM cannot be considered correctly by 2-dimensional analysis because of the shape of CPM. Finally, the optimum designing of CPM which control accurately the electron beam deflection in CRT(Cathode Ray Tube) was possible using 3-dimensional magnetic field analysis result.

• Journal of Ship and Ocean Technology
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• 제3권3호
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• pp.13-24
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• 1999

In this paper, a 2-dimensional novel beam element is developed and a method to replace the 3-dimensional analysis with 2-dimensional analysis is proposed. The developed novel beam element named rigid-ended beam element can consider the effect of three kinds of span points within one element, which was impossible in modeling with the ordinary beam element. Calculated results for the portal frame using the rigid-ended beam element agree with the results using membrane element. And also, the proposed simplified 3- dimensional analysis method which includes two step analysis using influence coefficients shows good accuracy. Structural analysis using the rigid-ended beam element and the simplified 3-dimensional method is revealed to have good computing efficiency due to unnecessity of the elements corresponding to the brackets and simplification of 3-dimensional analysis.

• 산업기술연구
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• 제27권A호
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• pp.85-94
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• 2007

This study, regarding curved channel, was performed to compare and analyze hydraulic characteristics and the speed of water and water level for left bank and right bank through hydraulic model experiments and numerical analysis. Real channels that had characteristics of curved channel were selected as objectives. In order to easily operate one and two dimensional numerical analysis and comparison for total 2.4Km model channel, measuring point was set up as 200m. HEC-RAS model was applied as one dimensional numerical analysis program and SMS model was used as two dimensional numerical analysis program. In respect of speed of water, the average speed of water for right bank recorded 8.33m/s in a model experiment and 3.08m/s, 8.57m/s were average speed of water for right bank in one dimensional and two dimensional numerical analysis. The average speed of water of two dimensional numerical analysis was quite similar to that of model experiments. Also, as for water level, maximum observational errors between one and two dimensional numerical analysis for right and left bank of model experiments were 0.66m, 0.84m and 0.28m, 0.48m for each. It was found that two dimensional numerical analysis had a similar result to hydraulic model experiments. Accordingly, from the result of this study, two dimensional numerical analysis should be used rather than one dimensional numerical analysis, when numerical analysis for curved channel is conducted.

• 대한기계학회논문집
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• 제19권10호
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• pp.2617-2629
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• 1995

The flow through a centrifugal compressor rotor was calculated using the quasi-3-dimensional and fully 3-dimensional Navier-Stokes solution methods. The calculated results, obtained during the development of the computer codes for both methods are discussed. In the inviscid quasi 3-dimensional analysis, stream function formulation was used for the blade to blade (B-B) plane calculations, and the streamline curvature method was used for the meridional (H-S) plane calculations. In the viscous 3-dimensional flow analysis, a control volume method based on a general rotating curvilinear coordinate system was used to solve the time-averaged Navier-Stokes equations, and a standard k-.epsilon. model was used to obtain eddy viscosity. The quasi-3-dimensional analysis reasonably predicts the pressure distributions and requires much less computation time in the region where viscous effects are not strong; however, it fails to predict velocity field and loss mechanism through the impeller passage. The viscous 3-dimensional flow analysis shows reasonable pressure distributions and typical jet-wake flow field through the impeller passage. Secondary flow and total pressure distributions on cross-sectional planes explain the loss mechanisms through the impeller.

• 터널과지하공간
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• 제14권6호
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• pp.423-428
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• 2004

편의상 터널을 평면변형률조건으로 해석하는 경우가 많은데 이때 록볼트는 등가의 연속체로 가정하여 해석한다. 본 연구에서는 3차원해석과2차원 해석을 비교하여 현행의 2차원 해석이 타당한지를 평가하였다. 해석결과 불량한 지반에 대한 2차원 해석에서는 $10\%$ 이상의 변형 오차가 발생하여 3차원적 고려가 필요한 것으로 판단되었다.

• 산업기술연구
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• 제28권B호
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• pp.193-198
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• 2008

When the existing polder levee was constructed, the river's numerical analysis decided the bank raise by applying the planned flood stage or by using the result from the sectional 1st dimensional numerical analysis. But, it was presented that there is a limitation in the 1st dimensional value analysis when the structure like the polder levee obstructs the special shaped running water flow. Therefore, in order to verify the numerical value applicability when the polder levee is constructed, this report compared each other through the 1st and 2nd dimensional numerical analysis and the mathematical principle model laboratory. In case of the polder levee construction through the numerical analysis and the mathematical principle model laboratory, it was decided that there was no big problem in the 1st dimensional numerical analysis applied design, considering the uncertainty of mathematical principle analysis though the first dimensional numerical analysis was calculated a little bigger than the second. But, after construction, it was found that the water level deviation of the 1st, 2nd occurred biggest at the place where the flow was divided into two. Also, as a result of comparing the 1st, 2nd dimensional numerical analysis with the mathematical principle model laboratory, it was confirmed that the 1st numerical analysis applied design decreased the modal safety largely, as the left side water level was calculated smaller more than 0.5m in case of the 1st dimensional numerical analysis.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제45회 KOSCO SYMPOSIUM 초록집
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• pp.75-78
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• 2012

Rotary kiln furnace is one of the most widely used reactors in industrial field. In this paper, 0-dimensional heat and mass balance for direct coal flame rotary kiln was performed preferentially, then a simplified 1-dimensional model was developed based on 0-dimensional analysis data to proceed additional thermal analysis. Compared the results with the currently operating rotary kiln data to validate 1-dimensional model. Through this procedure, it can help to derive fundamental idea for design and operation of rotary kiln.