• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.16-22
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• 2019

Off-line programming and robot calibration through simulation are essential when setting up a robot in a robot automation production line. In this study, we developed a new robot calibration method to match the CAD data of the production line with the measurement data on the site using 3D scanner. The proposed method calibrates the robot using 3D point cloud data through Iterative Closest Point algorithm. Registration is performed in three steps. First, vertices connected by three planes are extracted from CAD data as feature points for registration. Three planes are reconstructed from the scan point data located around the extracted feature points to generate corresponding feature points. Finally, the transformation matrix is calculated by minimizing the distance between the feature points extracted through the ICP algorithm. As a result of applying the software to the automobile welding robot installation, the proposed method can calibrate the required accuracy to within 1.5mm and effectively shorten the set-up time, which took 5 hours per robot unit, to within 40 minutes. By using the developed system, it is possible to shorten the OLP working time of the car body assembly line, shorten the precision teaching time of the robot, improve the quality of the produced product and minimize the defect rate.

• Journal of Dental Rehabilitation and Applied Science
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• v.24 no.3
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• pp.231-242
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• 2008

Purpose: The purpose of this study was to investigate the bond strength of the core-veneer interface in all ceramic systems. Material and Methods: The all ceramic systems tested with their respective veneer were IPS Empress 2 with IPS Eris, IPS e.max Press with IPS e.max Ceram and IPS-e.max ZirCAD with IPS e.max Ceram. Cores (N=36, N=12/group, diameter: 10mm, thickness: 3mm) were fabricated according to the manufacturer's instruction and cleaned with ultrasonic cleaner. The veneer(diameter: 3mm, thickness: 2mm) were condensed in stainless steel mold and fired on to the core materials. After firing, they were again ultrasonically cleaned and embedded in acrylic resin. The specimens were stored in distilled water at $37^{\circ}C$ for 1 week. The specimens were placed in a mounting jig and subjected to shear force in a universal testing machine(Z020, Zwick, Germany). Load was applied at close to the core-veneer interface as possible with crosshead speed of 1.00mm/min until failure. Average shear bond strengths(MPa) were analyzed with a one-way analysis of variance and the Tukey test(${\alpha}=.05$). The failed specimens were examinated by scanning electron microscopy(JSM-6360, JEOL, Japan). The pattern of failure was classified as cohesive in core, cohesive in veneer, mixed or adhesive. Results: The mean shear bond strength($MPa{\pm}SD$) were IPS e.max Press $32.85{\pm}6.75MPa$, IPS Empress 2 $29.30{\pm}6.51MPa$, IPS e.max ZirCAD $28.10{\pm}4.28MPa$. IPS Empress 2, IPS e.max Press, IPS e.max ZirCAD were not significantly different from each others. Scanning electron microscopy examination revealed that adhesive failure did not occur in any all ceramic systems. IPS Empress 2 and IPS e.max Press exhibited cohesive failure in both the core and the veneer. IPS e.max ZirCAD exhibited cohesive failure in veneer and mixed failure.

• Journal of Industrial Convergence
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• v.20 no.8
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• pp.85-96
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• 2022

The aim of this retrospective study was to compare risk factors between men and women through secondary data of nursing information and medical records according to the severity classification in patients of 340 men and 221 women with coronary artery disease(CAD) who were admitted for the first time at a general hospital and underwent first coronary artery angiography. Consequently, men presented with risk factors such as age(p=.004), total cholesterol(p=.040), triglycerides(p=.049), HbA1c(p<.001), smoking(p<.001), alcohol consumption(p=.002) and comorbidities(p=.036) that showed statistically significant differences. Among women, age(p=.002) and comorbidities (p=.018) were the only factors that showed significant differences. Significant risk factors influencing the classification of CAD severity in men were total cholesterol (OR 0.97, 95% CI 0.96-1.00, p=.014) in 1VD, alcohol consumption (OR 52.47, 95% CI 2.99-91.95, p=.007)in 2VD, and total cholesterol in the 3VD(OR 0.98, 95% CI 0.95-0.98, p=.026). A significant risk factor affecting the classification of CAD severity in women was comorbidity (OR 0.30, 95% CI 0.11-0.82, p=.020) in the 3VD. This study identified the importance of nursing care for male CAD patients, such as smoking cessation and quitting drinking, blood sugar control, cholesterol, and accompanying disease management, and provided evidence of individually tailored nursing care.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.9_10 s.157
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• pp.1485-1493
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• 2006

This study was to investigate the effect of different scouring methods on mechanical properties and appearance of lyocell. Two different scouring methods were adopted for the study; one was the traditional scouring with alkali and the other was enzymatic scouring. Enzymatic scouring was carried with four different enzymes; C1 : Cellusoft L, C2 : Cellusoft UL, D1 : Denimax 992L, D2 : Denimax Acid XCL. The mechanical properties of scoured lyocell were measured using KES-FB. The appearance of scoured samples was analyzed by 3D CAD SYSTEM of i-Designer. While the untreated fabric showed the best linearity because it is stiff, alkali treated samples showed the worst dimensional stability and distorted easily. Enzyme treated samples, especially C1 treated samples showed the best dimensional stability. In addition, enzyme treated samples showed low bending rigidity compared to the alkali treated samples. It means that the enzyme treated samples are more flexible than alkali treated samples. However, the smoothness of the sample's surface treated by either of methods did not show much difference. From the study, it was suggested that the enzymatic scouring for lyocell could help to gain natural silhouette.

• Journal of dental hygiene science
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• v.14 no.3
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• pp.349-355
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• 2014

The purpose of this study was to evaluate marginal gap of fixed dental prostheses (FDPs) fabricated by soft metal material with using dental computer aided design/computer aided manufacturing (CAD/CAM) system and to compare gap of its by a conventional method. Ten same cases of study models were manufactured and scanned for digital models fabricating. Ten FDPs were fabricated by soft metal material using dental CAD/CAM (SMB group). Then, ten FDPs were fabricated by cast metal using lost wax technique and casting method (LWC group). Marginal gap was measured by silicone replica technique. Gap was measured by digital microscope (${\times}160$). Mann-Whitney test for statistical analysis was executed (${\alpha}=0.05$). The mean (standard deviations) of marginal gap was $76.5{\mu}m$ (35.2) for the SMB group, and $82.9{\mu}m$ (22.1) for the LWC group. Statistically significant differences were not found between SMB and LWC. As results, FDPs fabricated by soft metal material were clinically acceptable range.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.1
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• pp.77-83
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• 2016

Pipe working is consist of design, making and installation. Pipe line is consist of spool pipes which are made in fabrication shop. And these spool pipes installation in shipyard. Spool pipes are designed based 2D Drawings(ISO Drawing), so spool pipes are not considered working area, that wake decreasing working efficiency and delay working time. In this paper, suggest make spool pipe design method using analysis working area about 3D CAD model and genetic algorithm.

• The korean journal of orthodontics
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• v.49 no.2
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• pp.73-80
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• 2019

Objective: The purpose of this study was to compare the static (SFF) and kinetic frictional forces (KFF) of a computer-aided design and computer-aided manufacturing lingual bracket (CAD/CAM-LB) with those of conventional LB (Con-LB) and Con-LB with narrow bracket width (Con-LB-NBW) under 3 tooth displacement conditions. Methods: The samples were divided into 9 groups according to combinations of 3 LB types (CAD/CAM-LB [Incognito], Con-LB [7th Generation, 7G], and Con-LB-NBW [STb]) with 3 displacement conditions (no displacement [control], maxillary right lateral incisor with 1-mm palatal displacement [MXLI-PD], and maxillary right canine with 1-mm gingival displacement [MXC-GD]; n = 6/group). While drawing a 0.016-inch copper or super-elastic nickel-titanium archwire with 0.5 mm/min for 5 minutes in a chamber maintained at $36.5^{\circ}C$, SFF and KFF were measured. The Kruskal-Wallis method with Bonferroni correction was performed. Results: The Incognito group demonstrated the highest SFF, followed by the 7G and STb groups ([STb-control, STb-MXLI-PD, Stb-MXC-GD] < [7G-MXC-GD, 7G-MXLI-PD, 7G-control] < [Incognito-MXLI-PD, Incognito-control, Incognito-MXC-GD]; p < 0.001). However, there were no significant differences in SFF among the 3 displacement conditions within each bracket group. Within each displacement condition, the Incognito group demonstrated the highest KFF, followed by the 7G and STb groups ([STb-control, STb-MXLI-PD] < Stb-MXC-GD < 7G-MXLI-PD < [7G-control, 7G-MXC-GD] < [7G-MXC-GD, Incognito-MXLI-PD, Incognito-control] < [Incognito-control, Incognito-MXC-GD]; p < 0.001). MXC-GD exhibited higher KFFs than MXLI-PD in the same bracket group. Conclusions: The slot design and ligation method of the CAD/CAM-LB system should be modified to reduce SFF and KFF during the leveling/alignment stage.

• The Research Journal of the Costume Culture
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• v.28 no.3
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• pp.299-312
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• 2020

The purpose of this study is to create a shirt sloper suitable for an elderly male body shape by producing virtual models using a 3D-virtualization program, making a torso prototype using the Yuka CAD system, and employing 3D simulation to virtualize and calibrate the model. First, the following three types of obese dummies are implemented through the CLO 3D program: Type 1 exhibits body fat in the lower body; Type 2 exhibits an obese abdomen; and Type 3 displays a balanced form of obesity. Second, for the design of the shirt pattern, the waist back length (measured value+1), back armhole depth (C/10+12+3+0.5~1.5), front armhole depth (back armhole depth 0~1), front interscye (2C/10-1+0.5-0.5), armscye depth (C/10+2+3.5+ 0.5), back interscye (2C/10-1+1), front chest C (C/4+2.5+1), back chest C (C/4+2.5-1), front hem C (C/4+2.5+1(+2)), back hem C (C/4+2.5-1(+2)), cap height (AH/3-5), and biceps width (Front AH-1, Back AH-1) are calculated. Third, the virtual attachment of the shirt pattern is resolved by increasing the front and back armhole depths, and the front and rear wrinkles are improved by adding a back armhole dart. The front hem lift and lateral pull caused by the protrusion of the abdomen are amended by increasing the margin of the chest, waist C, and hip C, with the appearance improved by balanced margin distribution in the front, back, and side panels. The improved retail pattern with an increase in the front armholes C was balanced on the torso plate.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.2
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• pp.257-264
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• 2020

Vectorization is currently the main method in feature collection (extraction) during digital mapping using UAV-Photogrammetry. However, this method is time consuming and prone to gross elevation errors when extracted from a DSM (Digital Surface Model), because three-dimensional feature coordinates are vectorized separately: plane information from an orthophoto and height from a DSM. Consequently, the demand for stereo plotting method capable of acquiring three- dimensional spatial information simultaneously is increasing. However, this method requires an expensive equipment, a Digital Photogrammetry Workstation (DPW), and the technology itself is still incomplete. In this paper, we evaluated the accuracy of low-cost stereo plotting system, Menci's StereoCAD, by analyzing its three-dimensional spatial information acquisition. Images were taken with a FC 6310 camera mounted on a Phantom4 pro at a 90 m altitude with a Ground Sample Distance (GSD) of 3 cm. The accuracy analysis was performed by comparing differences in coordinates between the results from the ground survey and the stereo plotting at check points, and also at the corner points by layers. The results showed that the Root Mean Square Error (RMSE) at check points was 0.048 m for horizontal and 0.078 m for vertical coordinates, respectively, and for different layers, it ranged from 0.104 m to 0.127 m for horizontal and 0.086 m to 0.092 m for vertical coordinates, respectively. In conclusion, the results showed 1: 1,000 digital topographic map can be generated using a stereo plotting system with UAV images.

• Korean Journal of Crystallography
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• v.13 no.2
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• pp.86-90
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• 2002

The structure of N-(Diphenylmethylene)aminomethylphosphonate has been determined by X-ray diffraction methods. The crystal system is triclinic, space group P(equation omitted), unit cell constants, a＝8.967(2) (equation omitted), b＝9.309(2) (equation omitted), c＝ 10.981(2) (equation omitted), α＝101.42(2)°, β＝92.22(2)°, γ＝92.23(2)°, V=896.8(3) (equation omitted), T＝296 K, Z＝2, D/sub c/＝1.227 Mgm/sup -3/. The intensity data were collected on an Enraf-Nonius CAD-4 Diffractometer with graphite monochromated MoKα radiation (λ＝0.7107(equation omitted)). The molecular structure was solved by direct methods and refined by full-matrix least-squares to a final R＝7.3% for 979 unique observed F/sub o/>4σ(F/sub o/) refections and 209 parameters.