• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.1704-1709
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• 2000

This paper proposes a spherical probe allowing acoustic intensity measurements in three dimensions to be made, which creates a diffracted field that is well-defined, thanks to analytic solution of diffraction phenomena. Six microphones are distributed on the surface of the sphere along three rectangular axes. Its measurement technique is not based on finite difference approximation, as is the case for the ID probe but on the analytic solution of diffraction phenomena. In fact, the success of sound source identification depends on the inverse models used to estimate inverse diffraction phenomena, which has non-linear properties. In this paper, we introduce the concept of nonlinear inverse diffraction modeling using a neural network and the idea of 3 dimensional sound source identification with several tests.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.128-131
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• 2002

Three Dimensional measuring system using optical interference is greatly needed for semiconductor surface or optical surface. The application of this system are : MEMS product, semiconductor surfaces, optical components, precise machined surface, etc. In this paper, Interferometry based measurement system is introduced, which is nondestructive and noncontact inspection system. This system have relatively many advantage, compared with AFM/STM, SEM, Stylus, etc. The developed system can measure the surface topography with high precision and resolution, and with few seconds. And the associated software algorithm is also developed for the ultra precision 3D measuring surface. Various samples that is measured using this system is showed in the latter of this paper.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.131.5-131
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• 2001

A new measurement method to measure vibrational motions of objects is presented. The original principle is similar to the previous work that utilized a 3-facet mirror to obtain three dimensional positions and orientations of rigid bodies. While the previous work was presented for only stationary objects, in this paper, we newly investigate the feasibility of this method for dynamic applications. The 3-facet mirror that looks like a triangular pyramid having an equilateral cross-sectional shape. The mirror has three lateral reflective surfaces inclined 45 degrees to its bottom surface, and its mounted on the object whose motion is to be measured, As optical components, a He-Ne laser source and three position-sensitive detectors(PSD) are used. The laser beam is emitted from the He-Ne laser source located at the upright position and vertically incident to the top of the 3-facet ...

• Journal of the Korean Society for Precision Engineering
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• v.24 no.5
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• pp.62-67
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• 2007

A simple dimension measuring method for the measurement of human bust has been developed using projection moire. The 3-D data of a human bust was calculated from the 2dimensional image information obtained by the stripe using projection moire. The creation of 3-D geometric shape by digitizing real objects has been widely investigated in reverse engineering(RE). This procedure generally consists of three basic steps: data capture, data alignment and model reconstruction. In order to achieve a complete model, multiple scans must be taken and aligned.

• Fashion & Textile Research Journal
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• v.22 no.4
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• pp.495-503
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• 2020

This study classified lower body shape according to thigh and waist shape to improve the fit of skinny blue jeans in adult women in their 20s. We analyzed the three-dimensional automatic measurement data, three-dimensional indirect measurement data, and index data using the three-dimensional female (20-29 years old) body scan data provided by Size Korea (6^th Korean Human Dimensional Survey Project). Factor analysis was performed to classify body type. We selected and analyzed 34 items related to thigh shape based on index items, angle items, and protrusion amount items from 99 items; consequently, seven factors were extracted and 82.39% of the total variance was explained. Cluster analysis according to factor analysis classified it into 4 types, and a post-test Duncan test was conducted to classify thigh features according to classified types. As a result, the characteristics of lower body shape according to the thigh types of women in their 20s are as follows. Lower Body Type 1 is shape with a more prominent belly and less prominent thighs. Lower Body Type 2 is a slender body figure with larger hips. Lower Body Type 3 has more prominent thighs compared to the waist and belly. Lower Body Type 4 has both a prominent belly and prominent thighs.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.40 no.3
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• pp.123-129
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• 2014

Objectives: The aim of this study was to verify the concordance of the measurement values when the same cephalometric analysis method was used for two-dimensional (2D) cephalometric radiography and three-dimensional computed tomography (3D CT), and to identify which 3D Frankfort horizontal (FH) plane was the most concordant with FH plane used for cephalometric radiography. Materials and Methods: Reference horizontal plane was FH plane. Palatal angle and occlusal plane angle was evaluated with FH plane. Gonial angle (GA), palatal angle, upper occlusal plane angle (UOPA), mandibular plane angle (MPA), U1 to occlusal plane angle, U1 to FH plane angle, SNA and SNB were obtained on 2D cephalmetries and reconstructed 3D CT. The values measured eight angles in 2D lateral cephalometry and reconstructed 3D CT were evaluated by intraclass correlation coefficiency (ICC). It also was evaluated to identify 3D FH plane with high degree of concordance to 2D one by studying which one in four FH planes shows the highest degree of concordance with 2D FH plane. Results: ICCs of MPA (0.752), UOPA (0.745), SNA (0.798) and SNB (0.869) were high. On the other hand, ICCs of gonial angle (0.583), palatal angle (0.287), U1 to occlusal plane (0.404), U1 to FH plane (0.617) were low respectively. Additionally GA and MPA acquired from 2D were bigger than those on 3D in all 20 patients included in this study. Concordance between one UOPA from 2D and four UOPAs from 3D CT were evaluated by ICC values. Results showed no significant difference among four FH planes defined on 3D CT. Conclusion: FH plane that can be set on 3D CT does not have difference in concordance from FH plane on lateral cephalometry. However, it is desirable to define FH plane on 3D CT with two orbitales and one porion considering the reproduction of orbitale itself.

• International Journal of Precision Engineering and Manufacturing
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• v.5 no.3
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• pp.19-25
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• 2004

Pitch measurements of 150 nm one-dimensional grating standards were carried out using a contact mode atomic force microscopy with a high resolution three-axis laser interferometer. This measurement technique was named as the 'nano-metrological AFM'. In the nano-metrological AFM, three laser interferometers were aligned precisely to the end of an AFM tip. Laser sources of the three-axis laser interferometer in the nano-metrological AFM were calibrated with an I$_2$ stabilized He-Ne laser at a wavelength of 633 nm. Therefore, the Abbe error was minimized and the result of the pitch measurement using the nano-metrological AFM could be used to directly measure the length standard. The uncertainty in the pitch measurement was estimated in accordance with the Guide to the Expression of Uncertainty in Measurement (GUM). The primary source of uncertainty in the pitch-measurements was derived from the repeatability of the pitch-measurements, and its value was about 0.186 nm. The average pitch value was 146.65 nm and the combined standard uncertainty was less than 0.262 nm. It is suggested that the metrological AFM is a useful tool for the nano-metrological standard calibration.

• Archives of Plastic Surgery
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• v.35 no.3
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• pp.303-308
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• 2008

Purpose: The purpose of this study is to develop three-dimensional computerized anthropometry(3DCA) and to compare its reliability and accuracy 3DCA with manual anthropometry(MA) for measurement of lips and nasal deformities in unilateral cleft lips and palate(UCLP) patients. Methods: Samples were consisted of six UCLP patients whose facial plaster models were available immediately before and 3 months after the cleft lip surgery. MA of the facial plaster models was carried out using an electronic caliper. In 3DCA, three-dimensional auto-measuring program was used to digitize landmarks and to measure three-dimensional virtual facial models (3DVFM), which was generated with a laser scanner and 3D virtual modeling program. Intraclass correlation coefficients(ICC) were calculated to evaluate reliability and reproducibility of the variables in both methods, and Wilcoxon's signed rank test was done to investigate the difference in values of the same variables of facial models of each patient between two methods. Results: All ICC values were higher than 0.8, so both methods could be considered reliable. Although most variables showed statistical differences between two methods(p<0.05), differences between mean values were very small and could be considered not significant in clinical situation. Conclusion: In clinical situation, 3DCA can be an objective, reliable and accurate tool for evaluation of lips and nasal deformities in the cleft patients.

• Archives of Plastic Surgery
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• v.43 no.5
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• pp.430-437
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• 2016

Background Accurate breast volume assessment is a prerequisite to preoperative planning, as well as intraoperative decision making in breast reconstruction surgery. The use of three-dimensional surface imaging (3D scanning) to assess breast volume has many advantages. However, before employing 3D scanning in the field, the tool's validity should be demonstrated. The purpose of this study was to confirm the validity of 3D-scanning technology for evaluating breast volume. Methods We reviewed the charts of 25 patients who underwent breast reconstruction surgery immediately after total mastectomy. Breast volumes using the Axis Three 3D scanner, water-displacement technique, and magnetic resonance imaging (MRI) were obtained bilaterally in the preoperative period. During the operation, the tissue removed during total mastectomy was weighed and the specimen volume was calculated from the weight. Then, we compared the volume obtained from 3D scanning with those obtained using the water-displacement technique, MRI, and the calculated volume of the tissue removed. Results The intraclass correlation coefficient (ICC) of breast volumes obtained from 3D scanning, as compared to the volumes obtained using the water-displacement technique and specimen weight, demonstrated excellent reliability. The ICC of breast volumes obtained using 3D scanning, as compared to those obtained by MRI, demonstrated substantial reliability. Passing-Bablok regression showed agreement between 3D scanning and the water-displacement technique, and showed a linear association of 3D scanning with MRI and specimen volume, respectively. Conclusions When compared with the classical water-displacement technique and MRI-based volumetry, 3D scanning showed significant reliability and a linear association with the other two methods.

• 제어로봇시스템학회:학술대회논문집
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• 1995.10a
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• pp.138-141
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• 1995

This paper describes a 3-dimensional measuring method for cylindrical huge ingot pressed with forging machine. Target ingot we consider here is rotated around a fixed axis during measurement. Using an image processing technique every profile of cross-section is obtained, and 3D image is reconstructed. One method to calibrate the system setting is also presented. Experimental results reveal that the method are applicable and the algorithm is feasible.