• Journal of Energy Engineering
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• v.15 no.1 s.45
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• pp.1-7
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• 2006

The multi-dimensional two-phase flow models were developed for analyze the multi-dimensional behaviors or nuclear systems. To verify the simple turbulence model, The single phase mixing problem in a rectangular slab was calculated and compared with the commercial CFD code results. That result shows a good agreement with the CFD result. And the RPI Air-water experiments were simulated to assess the two-phase turbulence model in the multi-dimensional component. The first calculated distribution or void-fraction is highly dispersed and diffusive. It was revealed that the main reason is undesirable stratification force in a horizontal stratified flow regimes. Therefore the horizontally stratified flow regime is deleted because the stratified flow regime is not expected in multi-dimensional flow. With the modification of the flow regime, the predicted flow patterns and void fraction profiles are in good agreement with the measured data.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.1
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• pp.225-231
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• 2003

In order to improve efficiency of a system with three-dimensional flow characteristics, this paper presents a new method that overcomes three-dimensional effects by using two-dimensional CFD and response surface method. The method was applied to shape optimization of cut-off in a multi-blade fan/scroll system. As the entrance conditions of two-dimensional CFD, the experimental values at the positions out of the inactive zone were used. In order to examine the validity of the two-dimensional CFD the distributions of velocity and pressure obtained by two-dimensional CFD were compared with those of three-dimensional CFD and experimental results. It was found that the distributions of velocity and pressure show qualitatively similarity. The results of two-dimensional CFD were used for constructing the objective function with design variables using response surface method. The optimal angle and radius of cut-off were determined as $72.4^{\circ}$ and 0.092 times the outer diameter of impeller, respectively. It is quantified the previous report that the optimal angle and radius of cut-off are approximately $72^{\circ}$ and 0.08 times the outer diameter of impeller, respectively.

• Proceedings of the Korea Contents Association Conference
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• 2004.05a
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• pp.207-214
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• 2004

The Qis visualizational spreadsheet environment is shown to be extremely effective in supporting the visualization of multi-gigabyte multi-dimensional data sets. The Qis has a novel framestack that is the 3-D arrangement of spreadsheet elements. It enables the visualization spreadsheet to effectively manage, rapidly organize, and compactly encapsulate multi-dimensional data sets for visualization. Using several experiments with scientific users, the Qis has been demonstrated to be a highly interactive visual browsing tool for the analysis o( multidimensional data, displaying 2-D 3-D graphics, and rendering in each frame of the spreadsheet.

• Proceedings of the KSRS Conference
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• v.2
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• pp.772-775
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• 2006

Muilti-dimensional feature vector matching algorithm uses multiple features such as intensity, gradient, variance, first or second derivative of a pixel to find correspondence pixels in stereo images. In this paper, we proposed a new method for adjusting automatically the weight of feature in multi-dimensional feature vector matching considering sharpeness of a pixel in feature vector distance curve. The sharpeness consists of minimum and maximum vector distances of a small window mask. In the experiment we used IKONOS satellite stereo imagery and obtained accurate matching results comparable to the manual weight-adjusting method.

• East Asian mathematical journal
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• v.28 no.1
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• pp.101-107
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• 2012

For each dimension exceeds 1, determining the number of multi-dimensional partitions of a positive integer is an open question in combinatorial number theory. For n ${\leq}$ 14 and d ${\geq}$ 1 we derive a formula for the function ${\wp}_d(n)$ where ${\wp}_d(n)$ denotes the number of partitions of n arranged on a d-dimensional space. We also give an another definition of the d-dimensional partitions using the union of finite number of divisor sets of integers.

• Tuberculosis and Respiratory Diseases
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• v.55 no.3
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• pp.239-249
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• 2003

Multi-detector row CT (MDCT) provides faster speed, longer coverage in conjunction with thin slices, improved spatial resolution, and ability to produce high quality muliplanar and three-dimensional (3D) images. MDCT has revolutionized the non-invasive evaluation of the central airways. Simultaneous display of axial, multiplanar, and 3D images raises precision and accuracy of the radiologic diagnosis of central airway disease. This article introduces central airway imaging with MDCT emphasizing on the emerging role of multiplanar and 3D reconstruction.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.04a
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• pp.137-140
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• 2005

Resin transfer molding (RTM) is one of the most popular processes for producing fiber reinforced polymer composites. In the manufacture of complex thick composite structures, analysis on flow front advancement on the resin impregnating the multi-layered fiber preform is helpful for the optimization of the process. In this study, three-dimensional mold filling simulation of RTM is carried out by using CVFEM (Control Volume Finite Element Method). On the assumption of isothermal flow of Newtonian fluid, Darcy’s law and continuity equation are used as governing equations. Different permeability tensors employed in each layer are obtained by experiments. Numerically predicted flow front is compared with experimental one in order to validate the numerical results. Flow simulations are conducted in the two mold geometries, rectangular plate and hollow cylinder. Permeability tensor of each layer preform in Cartesian coordinate system is transformed to cylinder coordinates system so that the flow within the multi-layered preforms of the hollow cylinder can be calculated exactly. Our emphasis is on the three dimensional flow analysis for circular three-dimensional braided preform, which shows outstanding mechanical properties such as high impact strength and toughness compared with other conventional two-dimensional laminar-structured preforms.

• Journal of the Korea Computer Industry Society
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• v.3 no.8
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• pp.1007-1018
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• 2002

A systematic and multi-dimensional analysis in evaluation results may play a role of providing both learners and instructors with essential information. Conventional types of evaluation research have a tendency of partiality for developing evaluation tools, and analyzing the evaluation results has mostly been fragmentary and a one-dimensional analysis. In this study, through analyzing evaluation results in a multi-dimensional way, a multi-dimensional evaluation result analyzing system was developed for the purpose of providing various information for both learners and instructors to accomplish quality learning teaching. Dimensions are classified into four dimensions including period, student, difficulty degree, and evaluation domain. Analysis results are presented in various types of Dcube, graphs, and spreadsheets.

• Journal of the Korean housing association
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• v.16 no.4
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• pp.121-129
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• 2005

The major goal of this study is drawing design plan factors considering residents' life cycle and life style when remodeling design is needed. By drawing such design factors, the study will propose an alternative remodeling design plan. Such design method was defined as Multi-Dimensional module design method. And constructing data-system based on Multi-Dimensional module was secondary goal in this study. The details are as follows: Based on analysis of Residents' demand for remodeling and features of emotion-design applied to remodeling, the system which is suitable for application in remodeling design method was conducted. Based on the type of construction materials, the level value was set up according to emotion-factor application. Also, by conducting coding operation according to the distinction of construction materials, this study seeks the unit drawing method of information for constructing emotion-information system.

• Transactions of Materials Processing
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• v.18 no.4
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• pp.283-289
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• 2009

The multi-stage shape drawing is used to obtain long shaped products with high levels of dimensional accuracy and quality. It is important to design the cross sectional shapes of the intermediate passes to meet the required dimensional accuracy of the final product in the multi-stage shape drawing. Until now, the cross sectional shapes of the intermediate passes have been designed by the experiences. It is still remained unsolved problem to design the cross sectional shapes of intermediate pass drawing dies in the multi-pass shape drawing. In this study, a new technique is proposed to design the cross sectional shapes of intermediate passes. The proposed method is applied to a multi-stage shape drawing for a LM-guide which is one of the representative shape drawing products. In order to verify the effectiveness of the proposed method, FE-simulation and experiments have been carried out. The dimensional accuracy of the proposed method is compared with that of the conventional shape drawing process designed by the industrial engineers.