• Journal of the Optical Society of Korea
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• v.18 no.1
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• pp.50-54
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• 2014

In this paper we studied the laser-induced crater depth, mass, and emission spectra of laser-ablated high-density polyethylene (HDPE) polymer using the laser-induced plasma spectroscopy (LIPS) technique. This study was performed using a Nd:YAG laser with 100 mJ energy and 7 ns pulse width, focused normal to the surface of the sample. The nanoscale change in ablated depth versus number of laser pulses was studied. By using scanning electron microscope (SEM) images, the crater depth and ablated mass were estimated. The LIPS spectral intensities were observed for major and minor elements with depth. The comparison between the LIPS results and SEM images showed that LIPS could be used to estimate the crater depth, which is of interest for some applications such as thin-film lithography measurements and online measurements of thickness in film deposition techniques.

• Journal of Dental Rehabilitation and Applied Science
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• v.28 no.1
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• pp.47-56
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• 2012

As attractive lips are important component of appealing faces, the study was conducted to investigate the association of mouth-breathing and thickness of lower lips in mouth-breathers and nasal-breathers. The subjects were 436 adolescent patients aged 8~18 years who took cephalometrics. The results were as follows. The ratio of lower lip thickness to that of upper lip thickness in mouth breathing and nasal breathing groups were $1.13{\pm}0.14$, $1.02{\pm}0.14$, respectively. According to subjects' skeletal pattern, the ratio in Class I sample was $1.05{\pm}0.09$. Class II subjects showed $1.20{\pm}0.12$, and Class III showed $0.97{\pm}0.11$. Mouth - breathers had higher lower/upper lip ratio than nasal breathers meaning their lower lips were thicker. Skeletal Class II patients group showed the most thickest lower lips among Class I, II, III subgroups.

• The korean journal of orthodontics
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• v.6 no.1
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• pp.17-24
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• 1976

The primary objective of this study was to define the differences that exist. between different sexes on the dentoskeletal framework and the soft tissue profile around the mouth. For the purpose of this study, cephalometric radiographs were obtained from the centric occlusion with closed lip position, through the research on each 42 males and females aged from 17 to 22 years with normal occlusion and acceptable facial appearence. The results were as follows: 1. Maxillary to mandibular relationships. Among the angles formed by the long axis of the maxillary and mandibular anterior teeth, the maxillary and mandibular anterior alveolar bone, and the lower and upper lips (Fig.2), only the angle formed by the lips was more acute in males than in females. The males have a more rounded profile, and the females have a flatter profile in the lower third of the face. The differences is statistically significant for the angle formed by the lips. The fact that the lips have a difference greater than that of teeth or the alveolar bone indicates that the lip position is not entirely due to tooth and bony support. Possibly the thickness of the lips has an influence. 2. Occlusal plane. The occlusal plane was related to the anterior tooth inclination, anterior alveolar bone profile, and the lip contour, both maxillary and mandibular (Fig.3). Only the angle related to lower lip was statistically significant. The females again had the more obtuse angle, indicating a flatter profile than that of the males. 3.Skeletal planes. The angles formed by the anterior maxillary lips, teeth, and alveolar bone with the Frankfort plane and the angles of the mandibular lips, teeth, and, alveolar bone and the mandibular plane were investigated (Fig.4). Results were similar to those from maxillary to mandibular relationships. The results were statistically significant for the upper lip and the lower lip, only. 4. Esthetics. The facial line and the mandibular plane were compared with the esthetic line. These angles were different for the different sexes, but only the latter was statistically significant. This difference may be due to the profile contour of the nose.

• Structural Engineering and Mechanics
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• v.24 no.3
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• pp.323-337
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• 2006

In this paper, the hysteretic behaviors of channel and C-section cold-formed steel members (CFSMs) under cyclic axial loading were simulated with the finite element method. Geometric and material nonlinearities, Bauschinger effect, strain hardening and strength improvement at corner zones were taken into account. Extensive numerical results indicated that, as the width-to-thickness ratio increases, local buckling occurs prematurely. As a result, the hysteretic behavior of the CFSMs degrades and their energy dissipation capability decreases. Due to the presence of lips, the hysteretic behavior of a C-section steel member is superior to that of its corresponding channel section. The intermediate stiffeners in a C-section steel member postpone the occurrence of local buckling and change its shapes, which can greatly improve its hysteretic behavior and energy dissipation capability. Therefore, the CFSMs with a large width-to-thickness ratio can be improved by adding lips and intermediate stiffeners, and can be used more extensively in residential buildings located in seismic areas.

• The korean journal of orthodontics
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• v.26 no.2 s.55
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• pp.141-151
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• 1996

This study was undertaken to assess the effect of growth on the lips. Not only does lip growth influence the stability of such orthodontic treatment; it also directly influence facial profile, in which the lips have an important part. An understanding of the growth of lips is thus central to a consideration of profile change in orthodontics. By analyzing the serial lateral cephalograms of 15 male and 15 female of 8 years old to 16 yaers old who have normal occlusion. The result of this study were summerized as follows; 1. The largest growth increments in the length of the lips was mod age of 14 in both sexes. 2. The thickness of lips showed lager value for the male than that of the female in the most age group. The lagest growth increments at A point was occured age of 14, while Ls, Li, B point decreased after the age of 10-11. 3. The largest increase in the interval between crest of lower lip and edge of upper incisors was occured between ages 9 and 11 in males. The interval decreased slightly from 8 to 16 years in females. 4. The nasolabial angle decreased slightly from 8 to 16 years in both sexes. 5. The mentolabial angle showed large variation.

• The korean journal of orthodontics
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• v.4 no.1
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• pp.21-29
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• 1974

The purpose of the present study is to evaluate changes of the soft tissue relative to underlying skeletal elements during orthodontic treatment, and the influence of orthodontic treatment quantitatively on various regions of the facial profile. 59 Korean young women were selected, whose Hellman dental age was IV A, IV C and V A. Lateral cephalometric head films were taken before and after orthodontic treatment. From tracings, landmarks on skeletal and soft tissue profile were located, and then their linear and angular measurements were made directly. The results were obtained as follow: 1) Soft tissues of the facial profile were closely related and dependent on the underlying dentoskeletal frameworks. Orthodontic treament resulted in the reduction of dentofacial protrusion with both upper and lower lips becoming less procumbent during treament. 2) Thickness of the upper lip increased considerably during orthodontic treatment, and this change was related to maxillary incisor retraction. The ratio between the amount of maxillary incisor retraction and that of increment of upper lip thickness was approximately 5:3. 3) Soft tissue thickness overlying Downs' point A, point B and pogonion was not modified by orthodontic treatment. 4) Holdaway's H line, relating facial profile to the underlying dentoskeletal framework, seemed to be the most practical approach to soft tissue analysis.

• The korean journal of orthodontics
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• v.14 no.1
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• pp.103-113
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• 1984

This work was undertaken to evaluate the integumental response in lower face to hard tissue changes, and to grope the prediction equation for expected integumental profile changes. Cephalometric headplates of 25 persons consisted of 8 Angle's class 1 maxillary protrusive and 17 Angle's class II division 1 patients whose mean age was 15.2 years were traced, diagramatized, and statistically analyzed. The results were as follows; 1. Upper incisor and lips were retracted and convexity of integumental profile decreased concurrently with decrease of hard tissue procumbency, however soft tissue point A', B', and Pog' did not undergo significant changes after orthodontic treatment. 2. Remarkable increment of upper lip thickness and upper lip height was shown and this was related to upper incisor retraction. The ratio between the amount of upper incisor retraction and the increment o f upper lip thickness was approximately 1.16:1. 3. Moderate correlation of upper lip retraction to upper incisor retraction, and of lower lip retraction to lower incisor movement were arranged, and yet comparatively wide variability from subject to subject was shown. 4. It was possible to predict statistically for horizontal alteration of lip position and change of upper lip angulation ground in orthodontic treatment.

• Journal of the korean academy of Pediatric Dentistry
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• v.11 no.1
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• pp.191-213
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• 1984

This study was made on the facial profile of the normal Korean children using the roentgenographic cephalograms. The subjects consisted 51 males and 47 females children of primary dentition with the normal occlusion and acceptable profile. For this study 13 soft tissue profile landmarks were plotted and 14 liner length, 9 soft tissue thickness, 8 vertical height length, 12 angles of soft tissue profile, and 2 vertical proportion were measured. The mean and standard deviations in the subjects were calculated and compared between male and female. The following results were obtained : 1. By the significant test, total facial convexity angle and soft tissue thickness were no significant difference between both sexes. 2. Lower facial height was greater than upper facial height in both sexes. 3. The vertical length of the upper and lower lips were 21.95 mm, 40.74 mm in male and 21.62 mm, 39.63 mm in female. 4. In the relationship of the upper lip and lower lip to the Ricketts' esthetic line, the male was 1.3 mm, 1.18 mm and the female was 1.16 mm, 1.27 mm front of the esthetic line. 5. Compared with the angulation of flush terminal plane group and mesial step group, the mesial step group was greater than the flush terminal plane group except the chin angle.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.1042-1047
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• 2001

A mechanistic model is developed to predict the thrust force and cutting torque of drilling process including wear. A mechanistic oblique cutting force model is used to develop the drilling force model. The cutting lips are divided into small elements and elemental forces are calculated by multiplying the specific cutting pressure with the elemental chip area. The specific cutting pressure is a function of chip thickness, cutting velocity, rake angle and wear. The total forces are then computed by summing the elemental forces. Measured cutting forces are in good agreement with the simulated cutting forces.

• The korean journal of orthodontics
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• v.12 no.2
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• pp.79-93
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• 1982

The purpose of orthodontic treatment is to achieve normal occlusion and good facial esthetics for individual patients. To produce harmonized facial balance, treatment planning for patient who require orthodontic treatment should include both a hard tissue and soft tissue cephalometric analysis. Author studied to derive the normal standards of soft tissue profile in Koreans by roentgenocephalometric analysis. For this study 12 soft tissue profile landmarks were plotted and 23 linear length, 9 soft tissue thickness, 8 vertical height length, 12 angles of soft tissue profile, and 3 vertical proportion were measured. The subjects consisted of 166 males and 209 females from 7 to 19 years with normal occlusion and acceptable profiles, and were divided into five groups according to age. The obtained results were as follows; 1. From the basis of N-Pog (Nasion-Pogonion) plane, the growth of facial soft tissue in the middle region especially nose area was greater than others facial region. 2. From the basis of G-Pog' (Glabella-soft tissue Pogonion) plane, the values of linear measurement of soft tissue Nasion and Inferior labial sulcus decreased and nose tip grew forward as growing older. 3. The growth of the facial soft tissue thickness was greatest in superior labial sulcus and the thickness of soft tissue nasion gradually became thinner as growing old. 4. The thickness of upper and lower lip was 14.47mm, 14.57mm in adulr male, 12.76mm, 13.78mm in adult female. 5. The soft tissue thickness of the lower lip was thicker than that of upper lip in all age groups and both sexes, 6. The vertical length of the upper and lower lips were 25.04mm, 49.97mm in adult male and 23.50mm, 48.39mm in adult female. 7. By the significant test, there were significant difference between male and female in fifth adult group on all vertical length measurements of lower face. 8. In fifth adult group, the perpendicular distance from LS, LI to Steiner's line and Ricketts' esthetic line were as follow; Steiner line to LS, LI were 7.98mm, 5.84mm in male. Steiner line to LS, LI were 6.71mm, 5.08mm in female. Ricketts' esthetic line to LS, LI were -0.40mm, 1.72mm in male. Ricketts' esthetic line to Ls, LI were -1.38mm 0.65mm in female. 9. In fifth adult group, the facial convexity angle and lower facial component angle were $171.17^{\circ}142.94^{\circ}$ in male and $172.5^{\circ}$, $144.41^{\circ}$ in female.