• Journal of Ship and Ocean Technology
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• v.3 no.3
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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.

• Journal of Biomedical Engineering Research
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• v.16 no.1
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• pp.25-32
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• 1995

Clinically, proximal bone resorption in the femur is frequently seen postoperatively on the follow up XI-rays after total hip replacement (THR). We developed the finite element model of cementless THR. The model is two dimensional side plate model, whereby the three dimensional structural integrity of the bone can be accounted for by a separate two dimensional mesh, a side plate. The subject of this article is the development and application of this two dimensional side plate FEM to study the reverse effect of the various degree of bone resorption of femur after THR. The results of this study indicates that 1) two dimensional side plate model is good and simple alternative to complex three dimensional model and 2) the severity of the proximal bone resorption has the effect of more increasing stress on the cortex at the level of femoral stem tip.

• Journal of the Korean Society for Heat Treatment
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• v.35 no.2
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• pp.66-73
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• 2022

Partial-hardened hot stamping has been well known to be very effective to absorb more energy in automotive lateral crash. Hardness distribution and dimensional change after partial-hardened hot stamping have been studied to find out effect of thermal deformation of the heated hot stamping die on dimensional accuracy of automotive center pillar. Soft zone of commercial center pillar showed 275~345 in Vickers hardness, indicating bigger non-uniformity which resulted from thermal deformation of heated die. Dimensional changes in soft zone of the commercial center pillar measured by three dimensional scanner were much bigger than that in hard zone. It has been found that hot stamping die compensation considering thermal deformation in soft zone causes a significant decrease in hardness deviation in the soft zone, corresponding to 20 percent of commercial center pillar and subsequently leads to much higher dimensional accuracy.

• The Journal of the Korea Contents Association
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• v.10 no.8
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• pp.18-25
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• 2010

The study has proposed a method that simultaneously takes advantage of each projection matrix acquired by using column-directional two-dimensional PCA(C2DPCA) and row-directional two-dimensional LDA(R2DLDA). The proposed method can acquire a great secure recognition rate, with no relation to the number of training images, with acquired low-dimensional feature matrixes including both the horizontal and the vertical features of a face. Besides, in the alternate experiment of PCA and LDA to row-direction and column-direction respectively(C2DPCA & R2DLDA, C2DLDA & R2DPCA), we could make sure the system of 2 dimensional LDA with row-directional feature(C2DPCA & R2DLDA) obtain higher recognition rate with low dimension than opposite case. As a result of experimenting that, the proposed method has showed a greater recognition rate of 99.4% than the existing methods such as 2DPCA and 2DLDA, etc. Also, it was proved that its recognition processing is over three times as fast as that of 2DPCA or 2DLDA.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.22 no.2
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• pp.283-290
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• 1992

The purpose of this study was to evaluate the spatial relationship of facial bone more accurately. For this study, the three-dimensional images of dry skull were reconstructed using computer image analysis system and three-dimensional reconstructive program involved CT. The obtained results were as follows: 1. Three-dimensional reconstructive CT results in images that have better resolution and more contrast 2. It showed good marginal images of anatomical structure on both three-dimensional CT and computer image analysis system, but the roof of orbit, the lacrimal bone and the squamous portion of temporal bone were hardly detectable. 3. The partial loss of image data were observed during the regeneration of saved image data on three-dimensional CT. 4. It saved the more time for reconstruction of three-dimensional images using computer image analysis system. But, the capacity of hardware was limited for inputting of image data and three-dimensional reconstructive process. 5. We could observe the spatial relationship between the region of interest and the surrounding structures by three-dimensional reconstructive images without invasive method.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.23 no.2
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• pp.335-344
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• 1993

The purpose of this study was to clarify the spatial relationship of temporomandibular joint and to an aid in the diagnosis of temporomandibular disorder. For this study, three-dimensional images of normal temporomandibular joints were reconstructed by computer image analysis system and three-dimensional reconstructive program integrated in computed tomography. The obtained results were as follows: 1. Two-dimensional computed tomograms had the better resolution than three dimensional computed tomograms in the evaluation of bone structure and the disk of TMJ. 2. Direct sagittal computed tomograms and coronal computed tomograms had the better resolution in the evaluation of the disk of TMJ. 3. The positional relationship of the disk could be visualized, but the configuration of the disk could not be clearly visualized on three-dimensional reconstructive CT images. 4. Three-dimensional reconstructive CT images had the smoother margin than three-dimensional images reconstructed by computer image analysis system, but the images of the latter had the better perspective. 5. Three-dimensional reconstructive images had the better spatial relationship of the TMJ articulation, and the joint spaces were more clearly visualized on dissection images.

• Smart Media Journal
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• v.7 no.2
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• pp.15-22
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• 2018

Pupil tracking technologies can be used as an efficient information provider means that provides convenience to the user by connecting with a smart device. In this paper, we measure the distance of user gaze point using the pupil tracking device which produced by Pupil-labs, also shows the experimental result with analyzing accuracy and precision. Based on that the pupil gaze point location which tracked by pupil tracking device is compared with object target in terms of error. Since the mobile pupil tracking device is also one kind of camera, we have to perform the calibration before using the device. Not only generally used 2-dimensional calibration, but also 3-dimensional calibration method is explained. To get the improved accuracy of 2-dimensional calibration result, the 3-dimensional calibration set an imaginary plane and executes the calibration in various 3-dimensional spaces. To show the efficiency of 3-dimensional calibration, we analyze the experimental result. It also introduces various using methods and information that can be obtained through the device.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.894-898
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• 2011

The first example of lead compound from $Pb(NO_3)_2$ and $H_3L$ N-heterocyclic ligand $(H_3L\;=\;(HO_2C)_2(C_3N_2)(C_3H_7)CH_2(C_6H_4)(C_6H_3)CO_2H)$, $[Pb_4(L')_4]{\cdot}5H_2O$ 1 (L' = OOC$(C_3H_7)(C_3N_2)CH_2(C_6H_4)(C_6H_3)COO)$, has been obtained under hydrothermal condition by decarboxylation, and characterized by elemental analysis, IR, TGDTA, and single-crystal X-ray diffraction. Compound 1 possesses a rare two-dimensional upper-lower offset terrace-like layer structure. In 1, crystallographic distinct Pb(II) ion adopts five-coordination geometry, and two lattice water molecules occupy the voids between 2-D layers. Results of solid state fluorescence measurement indicate that the emission band 458 nm may be assigned to $\pi^*-n$ and $\pi^*-\pi$ electronic transitions within the aromatic systems of the ligand L', however, the emission bands centred at 555 nm, 600 nm and 719 nm may be derived from phosphorescent emission ($\lambda_{excitation}$ = 390 nm).

• 한국전산유체공학회:학술대회논문집
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• 2003.08a
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• pp.11-17
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• 2003

The new multi-dimensional higher order interpolation scheme called MHIS is developed. Firstly, multi-dimensional TVD condition is derived based on one-dimensional TVD condition. Using multi-dimensional TVD condition, 2nd, 3rd and 5th order MHIS are presented. By help of multi-dimensional TVD condition, it is possible to captured a discontinuity monotonically even in a multi-dimensional flow. It is verified through several test cases that the accuracy and the robustness of MHIS are enhanced in regions of shock discontinuities as well as boundary-layers.

• Communications of the Korean Mathematical Society
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• v.24 no.2
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• pp.265-275
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• 2009

The object of the present paper is to study 3-dimensional normal almost contact metric manifolds satisfying certain curvature conditions. Among others it is proved that a parallel symmetric (0, 2) tensor field in a 3-dimensional non-cosympletic normal almost contact metric manifold is a constant multiple of the associated metric tensor and there does not exist a non-zero parallel 2-form. Also we obtain some equivalent conditions on a 3-dimensional normal almost contact metric manifold and we prove that if a 3-dimensional normal almost contact metric manifold which is not a ${\beta}$-Sasakian manifold satisfies cyclic parallel Ricci tensor, then the manifold is a manifold of constant curvature. Finally we prove the existence of such a manifold by a concrete example.