• 한국연소학회:학술대회논문집
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• 1999.10a
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• pp.55-61
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• 1999

A convolution algorithm combined with Fourier transformation is applied to the tomographic reconstruction of the asymmetric soot structure to identify the local soot volume fraction distribution. The line of sight integrated data from light extinction measurement with multi-angular scanning form basic information for the deconvolution. Multi-peak following interpolation technique is applied to obtain the effect of increasing number of scanning angles. Measurement of LII signal for the same flame shows the validity of this reconstruction technigue.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10a
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• pp.791-796
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• 1987

In this paper, an efficient algorithm to estimate the volume and surface area from ultrasonic imaging and a reconstruction algorithm to generate three-dimensional graphics are presented. The computing efficiency is Improved by using the graph theory and the algorithm to determine proper contour points is performed by applying several tolerances. The search for contour points is limited by the change in curvature in order to provide an efficient search of the minimum cost path. These algorithms are applied to a selected mathematical model of ellipsoid. The results show that the measured value of the volume and surface area for the tolerances of 1.0005, 1.001 and 1.002 approximate to the measured values for the tolerance of 1.000 resulting in small errors. The reconstructed 3-dimensional Images are sparse and consist of larger triangular tiles between two cross sections as tolerance is increased.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.197-200
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• 1997

In this paper, we present a 3D reconstruction method of color volume data or a computerized human atlas. Binary volume rendering which takes the advantages of shear-warp factorization and new normal vector calculation method visualizes 3D organs in real time. Various manipulations such as rotation, multiple object rendering, removal, and transparency effect improve the usefulness and comprehensiveness of the computerized atlas.

• Restorative Dentistry and Endodontics
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• v.29 no.5
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• pp.413-422
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• 2004

Established microleakage tests have their own disadvantages. In this study, 3D reconstruction method was tried to overcome these disadvantages. Four types of microleakage tests were used and relationships among them were estimated: penetrated dye volume: marginal adaptability: degree of dye penetration and relative penetrated length to cavity wall. Twenty-four Class V cavities were bulk filled with composite (Esthet X) following surface treatments: N group (no treatment): E group (etching only): T group (etching + Prime & Bond NT). 50% silver nitrate was used as a dye solution after thermocycling ($5^{\circ}C{\;}&{\;}55^{\circ}C$, 1.000 times). Teeth were serially ground with a thickness of 0.2 mm. Volume of dye penetration was estimated from a three-dimensionally reconstructed image with a software (3D-DOCTOR). Percentage of margin without gap was estimated from SEM and degree of dye penetration and the relative length of dye penetration to overall cavity wall were also estimated. ANOVA and Scheffe test for dye volume, Kruskal-Wallis and Mann-Whitney test for marginal quality, Spearman's rho test for checking of relationships among methods were used. The results were as follows: 1. Dye penetration could be seen from several directions, furthermore, its volumetric estimation was possible. 2. Reverse relationship was found between dye volume and marginal quality (r = -0.881/ p = 0.004). 3. Very low relationship was seen between dye volume and two-dimensional tests (degree of dye penetration and relative length). However, 2D evaluation methods showed high relationship (p = 0.002-0.054) each other. 4. Three times vertical section could be recommended as a 2D test.

• Journal of KIISE:Computer Systems and Theory
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• v.36 no.6
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• pp.511-520
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• 2009

In this paper, we present a new iso-density surface reconstruction scheme based on a hierarchy on the input volume data and the output mesh data. From the input volume data, we construct a hierarchy of volumes, called a volume pyramid, based on a 3D dilation filter. After constructing the volume pyramid, we extract a coarse base mesh from the coarsest resolution of the pyramid with the Cell-boundary representation scheme. We iteratively fit this mesh to the iso-points extracted from the volume data under O(3)-adjacency constraint. For the surface fitting, the shrinking process and the smoothing process are adopted as in the SWIS (Shrink-wrapped isosurface) algorithm[6], and we subdivide the mesh to be able to reconstruct fine detail of the isosurface. The advantage of our method is that it generates a mesh which can be utilized by several multiresolution algorithms such as compression and progressive transmission.

• Archives of Plastic Surgery
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• v.50 no.5
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• pp.478-487
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• 2023

Background The outcome of alveolar grafting with synthetic bone substitute (Osteon III) in various bone defect volumes is highlighted. Methods A prospective study was accomplished on 55 patients (6-13 years of age) with unilateral alveolar bone cleft. Osteon III, consisting of hydroxyapatite and tricalcium phosphate, is used to reconstruct the defect. Alveolus defect diameter was calculated before surgery (V1), after 3 months (V2), and finally after 6 months (V3) postsurgery. In the t-test, a significant difference and correlation between V1, V2, and V3 are stated. A p-value of 0.01 is considered a significant difference between parameters. Results The degree of cleft is divided into three categories: small (9 cases), medium (20 patients), and large (26 cases).The bone volume of the clefted site is divided into three steps: volume 1: (mean 18.1091 mm³); step 2: after 3 months, volume 2 resembles the amount of unhealed defect (mean 0.5109 mm³); and the final bone volume assessment is made after 6 months (22.5455 mm³). Both show statistically significant differences in bone volume formation. Conclusion An alloplastic bone substitute can also be used as a graft material because of its unlimited bone retrieval. Osteon III can be used to reconstruct the alveolar cleft smoothly and effectively.

• Archives of Plastic Surgery
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• v.33 no.3
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• pp.283-288
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• 2006

Various vascularized free flaps have been used for midfacial reconstruction after ablative head and neck cancer surgery. The most common donor sites for free flap include latissimus dorsi, rectus abdominis, and radial forearm. Between 1994 and 2004, 14 patients underwent free flap operation after head and neck cancer ablation, and were reviewed retrospectively. Among 14 free flaps, 8 were latissimus dorsi myocutaneous flaps, 3 rectus abdominis myocutaneous flaps and 3 radial forearm flaps, respectively. The overall survival rate of the flap was 100%. Complications were wound dehiscence(5 cases) and ptosis(1 case). We designed multiple dimensionally folded free flap for midfacial reconstruction. For 3-dimensional flap needs, we used latissimus dorsi myocutaneous flap. 2-Dimensional flap was latissimus dorsi or rectus abdominis myocutaneous flap and 1-dimensional flap was radial forearm flap. In this study we produced an algorithm for midfacial reconstruction. Large volume with many skin paddle defects were best reconstructed with latissimus dorsi myocutaneous flap or rectus abdominis myocutaneous flap. Radial forearm flap was used for reconstruction of small volume and little skin paddle defects.

• Archives of Plastic Surgery
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• v.38 no.4
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• pp.451-457
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• 2011

Purpose: As a central feature of the face, the nose has considerable significance in appearance and expression. Reconstruction of full thickness defects of the nasal ala has always been a challenge because of the 3-dimensional structure. For reconstruction of post burn defects of ala, skin graft, local or pedicled flap and composite graft are optionally available. We have reconstructed the ala defects using adiposocutaneous graft and observed the outcome. Methods: From March 2003 to December 2010, 19 cases in 11 patients with scar contracture and defect on ala portion were performed operation using adiposocutaneous graft. As a donor site, we used the inguinal crease and posterior auricular area and the donor site was primarily closed. We made incision through the superior rim of ala and released fully. A graft is applied to recipient site with larger size than recipient volume. Results: The mean age of the patient was 38.6 years (16~51), males are seven patients and females are four patients. The operation was performed bilaterally in 5 patients and unilaterally in 6 patients. Composite grafts were harvested from inguinal area in 13 cases and posterior auricular area in 6 cases. In one case, we did 4 times of operation to get enough volume. All the grafts were well taken. The mean size of the graft was 3.63 $cm^2$. Conclusion: For reconstruction of post burn defects of ala, it's not easy to use local flap or pedicled flap because of hardness and fibrosis of surrounding tissue. So, we choose adiposocutaneous graft for ala deformity reconstruction, got satisfactory outcome in color matching and texture.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.7
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• pp.1583-1590
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• 2011

As the existing radiation scanning systems use 2-dimensional radiation scanned images, the low accuracy has been pointed out as a problem of it. This research analyzes the applicability of the stereo image processing technique to X-ray scanned images. Two 2-dimensional radiation images which have different disparity values are acquired from a newly designed stereo image acquisition system which has one additional line sensor to the conventional system. Using a matching algorithm the 3D reconstruction process which find the correspondence between the images is progressed. As the radiation image is just a density information of the scanned object, the direct application of the general stereo image processing techniques to it is inefficient. To overcome this limitation of a stereo image processing in radiation area, we reconstruct 3-D shapes of the edges of the objects. Also, we proposed a new volume based 3D reconstruction algorithm. Experimental results show the proposed new volume based reconstruction technique can provide more efficient visualization for cargo inspection. The proposed technique can be used for such objects which CT or MRI cannot inspect due to restricted scan environment.

• Archives of Reconstructive Microsurgery
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• v.20 no.1
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• pp.57-59
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• 2011

Tongue reconstruction after oncologic resection with free flap is important to conserve function and shape. Vertical rectus myocutaneous free flap is usually used for total tongue reconstruction, but our patient was thin and primary closure after flap elevation seemed hard. So we used anterolateral thigh free flap to reduce donor site morbidity and to maintain bulk of the tongue as much as possible. Deepithelization of both middle side of flap and folding was done to mimic normal tongue base's shape and volume. Flap survived without complication and patient underwent concurrent chemoradiation therapy three weeks after surgery. Anterolateral thigh free flap can be good candidate for total tongue reconstruction especially in thin patient.