• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.3
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• pp.385-392
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• 2010

The breast types of middle-aged women of 80A (formerly 80B) size were classified through a 3D scanned nude body. Thirty seven measurements including the radius of curvature, surface area, volume, surface length, and breast displacements were used as input variables. We extracted five main factors through the factor analysis of the measurements and classified 36 subjects into 3 clusters through the cluster analysis. As a result of the factor analysis, the size of the breast, breast sag, the curvature of the inner and the outer breast curve, the width of the breast, and the nipple direction were found as the main factors. For the results of the classification of breast types, Cluster 1 was characterized by narrow breast width and unsymmetrical under the breast curve, whereas Cluster 2 was a wide and sagged shape. Cluster 3 was classified into big breast volume and symmetrical under-breast curve. The results are useful to the product development of high quality brassieres which reflect the 3D characteristics of breast types of middle-aged women.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.295-298
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• 2000

In this research, a novel sampling strategy for a CMM to inspect freeform surfaces is proposed. Unlike primitive surfaces, it is not easy to determine the number of sampling points and their locations for inspecting freeform surfaces. Since a CMM operates with slower speed in measurement than optical measuring devices, it is important to optimize the number and the locations of sampling points in the inspection process. When a complete inspection of a surface is required, it becomes more critical. Among various factors to cause shape errors of a final product, curvature characteristic is essential due to its effect such as stair-step errors in rapid prototyping and interpolation errors in NC tool paths generation. Shape errors are defined in terms of the average and standard deviation of differences between an original model and a produced part. Proposed algorithms determine the locations of sampling points by analyzing curvature distribution of a given surface. Based on the curvature distribution, a surface area is divided into several sub-areas. In each sub-area, sampling points are located as further as possible. The optimal number of sub-areas. In each sub-area, sampling points are located as further as possible. The optimal number os sub-areas is determined by estimating the average of curvatures. Finally, the proposed method is applied to several surfaces that have shape errors for verification.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.5
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• pp.691-699
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• 1997

The effects of concave hemispherical surface curvature on the local heat transfer from a turbulent round impinging jet were experimentally investigated. The liquid crystal transient method was used for these measurements. This method, which is a variation on the transient method, suddenly exposes a preheated wall to an impinging jet while video recording the response of liquid crystals for the measurement of the surface temperature. The Reynolds number ranges from Re=11,000 to 50,000, the nozzle-to- surface distance from L/d=2 to 10, and the surface curvature from D/d=6 to 12.The present results are also compared to those for the flat plate case. In the experiment, the local Nusselt numbers tend to increase in all regions with an increasing surface curvature. The maximum Nusselt number for all Reynolds numbers occurred at L/d .ident. 6 and a second maximum in the Nusselt number occurred at R/d .ident. 2 for both Re=23,000 and Re=50,000 in the case of L/d=2 and for Re=50,000 only in the case of L/d=4. Meanwhile, as the surface curvature increases, the value of the secondary maximum Nusselt number decreases. All the other cases exhibit monotonically decreasing values of the Nusselt number along the curved surface. The stagnation point Nusselt numbers are well correlated with Re, L/d, and D/d.

• Journal of Korean Ophthalmic Optics Society
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• v.11 no.3
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• pp.181-185
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• 2006

The measurement of the radius of corneal curvature with keratometer was followed in 184 university students who wearing RGP contact lens and consisted of female(167), male(17) and keratoconus patients(3). Overall mean value in the radius of corneal curvature is 7.77mm, and right and left eyes is appeared the same mean value. Overall mean value in horizontal and vertical is 7.88mm and 7.65mm. Horizontal means is larger than vertical means by 0.22mm of the all female and male students. Male's mean value in the radius of corneal curvature(7.84mm) is larger than female's by 0.08mm, and right and left eyes is also the same mean value. Keratoconus patients' mean value in the radius of corneal curvature(6.86mm) is smaller than others students by 0.91mm.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2001.10a
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• pp.61-63
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• 2001

Residual stress distribution in injection-molded short fiber composites was determined using layer-removal method. Polysterene with 3 vol% carbon fibers was injection-molded into the tensile specimen. With milling machine layer-removal process was conducted and the curvature data were acquired. Treuting and Read analysis which is assuming isotropic material, and White analysis considering anisotropy due to the fiber orientation were used to calculate residual stress of the flow direction through the thickness direction and compared with each other.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.1
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• pp.120-129
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• 1990

In this paper, 3-dimensional object segmentation and classification are proposed. Planar object is segmented surface using jump boundary and internal boundary. Curved object is segmented surfaces by maximin clustering method. Segmented surfaces are classified by depth trends and angle measurement of normal vectors. Classified surfaces are merged according to adjacent surfaces and compared to Guassian curvature and mean curvature method. The proposed methods have been successfully applied to the synthetic range images and shows good classification.

• Journal of radiological science and technology
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• v.30 no.4
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• pp.335-341
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• 2007

General anatomy classifies diaphragm as muscle of boundary between chest and abdomen, while radiology divides it into right and left hemidiaphragm, because it is more advantageous in radiological diagnosis on chest and abdomen. Based on these anatomic characteristics of diaphragm, this study aimed to measure the height and curvature of right and left diaphragm in simple chest radiography. As a result, this study came to the following conclusions : 1. For all subjects who joined this study, it was found that their mean transverse diameter in internal diameter of thorax(ID) amounted to 293.3 mm(min. 221.0 mm, max 335.3 mm). 2. For the right and left height of diaphragm, it was found that 81.4% showed higher right diaphragm ; 16.2% showed equivalent height between right and left diaphragm ; and only 2.4% showed higher left diaphragm. 3. For higher right diaphragm, it was found that the mean height of right diaphragm amounted to 15.2 mm(min. height = 2.0 mm, max. height = 41.7 mm). 4. For higher left diaphragm, it was found that the mean height of left diaphragm amounted to 11.5 mm(min. height = 4.7 mm, max. height = 30.4 mm). 5. The mean curvature of right diaphragm amounted to 22.9 mm(min. curvature = 10.4 mm, max. curvature = 37.3 mm). 6. The mean curvature of left diaphragm amounted to 22.4 mm(min. curvature = 11.3 mm, max. curvature = 42.2 mm). 7. For possible associations between ID and right/left diaphragm curvature, it was noted that ID was in significantly positive correlations with right diaphragm curvature(r= .427, p<.001) and left diaphragm curvature(r= .425, p<.001) on statistical level. 8. For possible associations between right and left diaphragm curvature, it was found that right diaphragm curvature was in significantly positive correlations with left diaphragm curvature(r= .403, p<.001).

• Journal of the Semiconductor & Display Technology
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• v.14 no.1
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• pp.1-5
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• 2015

This paper deals with the residual stresses developed in an epoxy film deposited on Si wafer. First, chemically induced residual stresses due to the volumetric shrinkage in cross-linking resins during polymerization are treated. The curvature measurement method is employed to investigate the residual stresses. Then, thermally induced stresses are investigated along the interface between the epoxy film and Si wafer. The boundary element method is employed to investigate the whole stresses in the film. The singular stress is observed near the interface corner. Such residual stresses are large enough to initiate interface delamination to relieve the residual stresses.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.9
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• pp.2145-2152
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• 1993

The objective of this paper is to examine the detection limit, growth characteristics and notch curvature radius in short crack problem. Measurement techniques such as ultrasonic method and back-face strain compliance method were adopted. The fatigue crack growth rate of the short crack is slower than that of a long crack for a notched specimen. The characteristic of crack growth and crack closure is same as the case of a delay of crack growth caused by constant amplitude load for an ideal crack or single peak overload for a fatigue crack. The short crack is detected effectively by ultrasonic method. A short surface crack occurs in the middle of specimen thickness and is transient to a through crack depth is larger than the notch curvature radius.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.18 no.1
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• pp.1-10
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• 2012

Thoracic kyphosis is occasionally used to describe someone with accentuated thoracic curvature, hyperkyphosis is preferred since kyphosis itself refers to the normal sagittal angle of thoracic curvature. The angle of thoracic kyphosis tends to increase with age resulting in hyperkyphosis in some individuals. The persons who suffer from hyperkyphosis are at increased risk for a variety of adverse health outcomes that include musculoskeletal alteration, physical functional limitations, poor quality of life, falls, and even earlier mortality. Hyperkyphosis may develop from vertebral fractures, degenerative disc disease, either muscle weakness, decreased mobility and sensory deficits. The gold-standard orthopaedic technique for assessment of thoracic kyphosis is standing lateral spine radiographs. Other clinical measures are Debrunner kyphometer, inclinometer, flexicurve ruler, arcometer, flexible electrogoniometer and spinal mouse.