• Tribology and Lubricants
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• v.20 no.2
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• pp.68-76
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• 2004

Applying a general Galerkin FE lubrication analysis method to spiral groove dry gas seals, this study intends to analyze in detail the effects of groove design parameters, such as a spiral angle, groove width ratio, groove radius ratio, groove depth ratio, and groove taper ratio, on the lubrication performances of an opening force, leakage, axial stiffness and damping, and angular stiffness and damping at low and high rotating speeds: 3,600 and 15,000 nm. Results show that, for the primary design consideration performances such as the opening force and axial and angular stiffnesses, a spiral angle of $25^{\circ}$, a groove width ratio of 0.46, a groove radius ratio of 1.1, a groove depth ratio of 1.0, and a groove taper ratio of 0.0 are preferred. Where the recommended relatively low values of groove depth and taper ratios are to keep the axial and angular dampings positive or higher than 0 particularly at the high rotating speed.

• Journal of Korean Medicine Rehabilitation
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• v.20 no.3
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• pp.93-107
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• 2010

Objectives : The purpose of this study was to assess the efficacy of Chuna and taping treatment in patients with genu varum. Methods : Twenty-seven patients(male:10, female:17) with genu varum were recruited in this study. Chuna treatment at pelvic, and taping treatment at both legs were applied to whole participants. Outcomes were assessed using Q-angle(Quadriceps angle, QA), tibiofemoral angle(TFA), width and length of lesser trochanter(LT), pelvic incidence(PI), pelvic(PT), sacral slope(SS), lumber lordosis angle(LLA), meridian-electromyography(MEMG), Korean western ontario and McMaster universities osteoarthritis index(KWOMAC), and distance of femoral intercondylar distance(ICD). Results : 1. QA, LT width and LT length in radiograph were significantly increased. 2. PI, SS, PT and TFA in radiograph were significantly decreased. 3. The left vastus medialis portion contraction of female was significantly decreased after treatment. 4. The left rectus femoris portion fatigue was significantly decreased after treatment in male subjects. 5. The vastus medialis portion fatigue was significantly decreased after treatment in female subjects. 6. The distance of femoral ICD was significantly decreased. Conclusions : This study showed that Chuna and taping treatment could be used as an effective method for the treatment of genu varum.

• Journal of Korean Foot and Ankle Society
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• v.14 no.2
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• pp.157-160
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• 2010

Purpose: The purpose of this study is to find out the correlation factors for prognosis of calcaneal fractures. Materials and Methods: 120 cases (feet) of calcaneal fractures, all of them followed up for more than 1 year after surgical procedures, consisted of 101 men (105 feet) and 13 women (15 feet) were reviewed retrospectively. The collected clinical data were as follows : injury mechanism, surgical procedures, time to procedure, time to work and the radiologic data: Bohler angle, heel width, displacement of posterior facet. AOFAS hindfoot score and VAS score were checked. With ANOVA test and multiple regression analysis, the data processed statistically. Results: According Sanders classification, type II was 37 cases (31%), type III 66 cases (55%), and type IV 17 cases (14%). On plane radiography, the Bohler angle improved to average 28.4 degree from 5.6 degree, and the displacement of posterior facet was corrected to average 1.2 mm. AOFAS hindfoot score was checked average 81.7 points postoperatively, and the meaningful difference existed between types of Sanders classification. The Bohler angle represented the outline of the calcaneus had the better correlation with the clinical outcome of calcaneal fractures rather than the anatomical reduction of the posterior facet did. And the width of calcaneus had good correlation with the clinical score. Conclusion: We should also concern about the outline of calcaneus, the width of calcaneus and the Bohler angle representing anatomical reduction, not only the acute reduction of the posterior facet.

• Journal of Oral Medicine and Pain
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• v.26 no.2
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• pp.147-156
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• 2001

The purpose of this study was to identify the difference of vertical movement of mandible according to Angle's molar relationship and by skeletal factors affect to vertical movement of mandible. 172(age ranged from 20 to 30) subjects who go to college within territory of Kwangju city without any experience of temporomandibular disorder, extraction and orthodontic treatment. were selected for this study. The subjects were classified into class I(male:30, female:49), class II(male:18, female:24) and class III(male:18, female:33) according to Angle's molar relationship. The distance was measured between incisal edge of maxillary and mandibular central incisor and between bottom of central fossa of maxillary and mandibular 1st molar with ruler. The arch length and width were measured on the diagnostic cast. Cephalometrics were taken and then traced. Landmarks were identified and analyzed. 1. Maximal interincisal opening of male is larger than that of female in class I, class II and class III. Among each group maximal interincisal distance is the largest in class III. Maximal intermolar distance of male is superior to that of female in class I, class II, and class III, but there is no siginficant difference among them. 2. On maximal opening movement of Angle's classification class I and class II, total mandibular length, mandibular ramal length, madibular inferior border length and upper arch width were important variables and facial length, upper arch length and lower arch length had negative relationship to that. On maximal opening movement of Angle's class III, the upper arch length, the lower arch length and anterior facial length were important variables especially when compared with class I and II, and upper arch width had negative relationship. These results suggest that maximal opening movement is affected by facial morphology in all classes, but each group is affected by different facial skeletal variables. Accordingly, facioskeletal variables might be considered as diagnosis and treatment to improve the amount of mouth opening.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.709-710
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• 2008

In this paper, we calculated permanent magnetic linkage flux ${\psi}_{\alpha}$ and Ld, Lq parameters of IPMSM and compared two model which has different barrier width. IPMSM has two kinds of torque that reluctance torque and magnetic torque. In constant torque region, using the Maxwell stress tensor method, we calculated the torque and current phase angle ${\beta}$ which has appeared maximum torque. In weakening flux region, we calculated the current phase angle ${\beta}$ which flux ${\psi}_o$ lower than limited flux ${\psi}_{omax}$. From the current phase angle ${\beta}$, we calculated torque by torque equation and compared two model characteristic.

• Transactions of Materials Processing
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• v.17 no.3
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• pp.203-209
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• 2008

In this paper, experimental investigation has been performed to analyze the forming process of toothed or serrated sheets, which is used as strap engaging surface of the seal to secure together overlapping portions of steel or plastic strapping ligature. Serration formed on the strap engaging surface of the seal prevent from relative slipping between overlapping ligatures after closing the seal. The geometry of tooth on the strap engaging surface is directly related to the quality of securing overlapping ligatures together. Inclined indentation followed by scratching operation has been proposed and applied to the experiments. Punch entry and face angles are selected as process variables to see the influence of these variables on the tooth geometry. Five different punch entry angles have been applied to experiments and three different punch face angles have been selected for each case of punch entry angle. Clay is selected as model material for experiments. Experimental results are summarized in terms of tooth height, tooth width, and aspect ratio such as tooth height to width ratio, respectively.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.2
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• pp.64-69
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• 2010

We investigated the variation in contact angle of a nano-sized water droplet on a nano stripe-patterned surface using molecular dynamics simulation. By changing the height and width of the stripe pillar, and the gap width of the stripes, we observed the contact angle of water droplet in equilibrium. When the surface energies were 0.1 and 0.3 kcal/mol, the calculated contact angles were in good agreement with the Cassie and Baxter equation. However, when the surface energy is 0.5 kcal/mol, the contact angles are observed to be perturbed along the Cassie and Baxter equation.

• The korean journal of orthodontics
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• v.40 no.5
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• pp.314-324
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• 2010

Objective: The purpose of this study was to determine differences of mandibular anterior alveolar bone thickness and symphysial cross sectional area in 9 different horizontal and vertical facial types. Methods: By using the initial cephalometric radiographs of 270 adult patients (male 135, female 135), the authors measured the buccolingual thickness of anterior alveolar bone on the basis of the root axis and symphysial cross sectional distance. Results: The high angle group showed significantly thinner buccolingual alveolar bone width except for the CEJ area and lingual alveolar bone width ($p$ < 0.05). The low angle group and Class I, II average group showed similar or significantly thicker alveolar bone width than the Class I average group ($p$ < 0.05). The Class III average group showed significantly thinner buccolingual and lingual alveolar bone width than Class I and II average groups ($p$ < 0.05). The Class III high angle group showed minimal alveolar bone width in all facial skeletal types. No significant difference was found in the symphysial cross sectional area of the different vertical facial skeletal types ($p$ > 0.05). Conclusions: The results of this study found that Class III high angle patients have thinner mandibular anterior alveolar bone thickness; therefore, more attention will be needed to determine the incisor position during orthodontic treatment for this group of patients.

• Journal of Korean Foot and Ankle Society
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• v.18 no.1
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• pp.14-18
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• 2014

Purpose: The purpose of this report is to evaluate the measured values of normal Korean calcaneus by conduct of a cadaveric study. Materials and Methods: A total of 42 calcanei were obtained from Korean cadavers. A digital goniometer was used for measurement of B$\ddot{o}$hler's angle, Gissane angle, posterior facet articular inclination angle, and Fowler-Philip angle of calcaneus. A vernier caliper was used for measurement of the maximal antero-posterior length, maximal transverse width, and maximal height of calcaneus. Results: The average B$\ddot{o}$hler's angle, Gissane angle, posterior facet articular inclination angle, and Fowler-Philip angle was $32.3^{\circ}{\pm}5.0^{\circ}$, $114.4^{\circ}{\pm}8.2^{\circ}$, $61.2^{\circ}{\pm}4.4^{\circ}$, and $60.3^{\circ}{\pm}7.6^{\circ}$. The average maximal antero-posterior length, maximal transverse width, and maximal height of calcaneus was $74.2{\pm}3.0mm$, $43.0{\pm}4.0mm$, and $42.5{\pm}3.0mm$. Conclusion: The measured values of normal Korean calcaneus were lower than the values reported in the international literature. Therefore, development of appropriate instruments reflecting the anatomical characteristics of Koreans will be needed.

• Archives of Craniofacial Surgery
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• v.10 no.2
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• pp.61-66
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• 2009

Purpose: The aim of this study is to establish anatomical dimension of the nose and nostril shape in Korean twenties. Methods: Authors measured anthropometry of nose in Korean youths 1,000 individuals (male 363, female 637) and analyzed stastically them. Results: The mean measurements are as follows. 1. The shape of nostrils was classified into 7 types by the angle between both long axis of nostril (male / female). Type I ($<40^{\circ}$)1.7% / 1.72%, Type II ($41-70^{\circ}$) 26.17% / 29.35%, Type III ($71-100^{\circ}$) 39.94% / 38.77%, Type IV (unclassified) 3.85% / 5.80%, Type V ($101-130^{\circ}$) 20.93% / 17.89%, Type VI ($131-180^{\circ}$) 7.43% / 5.96%, Type VII ($>180^{\circ}$) 0% / 0.47% 2. Lengths (male/female) Width of nasal root: $25.29{\pm}2.25mm/24.72{\pm}2.40mm$ Width of nose: $37.63{\pm}2.46mm/34.77{\pm}2.11mm$ Width of columella: $7.18{\pm}0.92mm/6.92{\pm}0.86mm$ Width of alar: $4.99{\pm}1.00mm/4.74{\pm}0.91mm$ Width of nostril floor: $10.98{\pm}1.40mm/10.13{\pm}1.73mm$ Protrusion of nasal tip: $17.12{\pm}1.95mm/16.88{\pm}1.84mm$ Length of alar: $27.10{\pm}2.21mm/24.66{\pm}2.18mm$ Length of nasal root: $17.37{\pm}2.51mm/16.08{\pm}2.90mm$ Depth of nasal root: $7.83{\pm}1.63mm/6.82{\pm}1.36mm$ Length of columella: $8.13{\pm}1.40mm/7.30{\pm}1.46mm$ Height of nose: $60.50{\pm}8.90mm/59.14{\pm}9.22mm$ Height of nasal bridge: $52.68{\pm}7.49mm/50.57{\pm}7.71mm$ 3. Angles Nasofacial angle: $30.19{\pm}3.43^{\circ}/29.13{\pm}6.31^{\circ}$ Nasofrontal angle: $134.88{\pm}7.25^{\circ}/139.94{\pm}6.33^{\circ}$ Nasolabial angle: $95.08{\pm}8.95^{\circ}/95.80{\pm}8.93^{\circ}$ 4. Nasal index: $72.60{\pm}9.57%/68.21{\pm}7.03%$ Nasal tip protrusion-nasal height index: $45.64{\pm}5.21%/47.09{\pm}5.21%$ Nasal tip protrusion-nasal width index: $32.61{\pm}6.83%/31.63{\pm}6.71%$ Conclusion: These data could be useful reference for anthropometry of nose in Korean twenties.