• Journal of the Korea institute for structural maintenance and inspection
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• v.9 no.4
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• pp.109-118
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• 2005

A concrete shear wall system is commonly adopted in high-rise residential apartment buildings. In the construction stage, a rectangular opening is often made for the convenience of horizontal movement of workers, and construction materials and equipment. In the case of safety or stability assessment of a shear wall, the cutout part can be a critical factor. Finite element method is adopted to investigate the elastic stability behavior of the perforated unit shear wall. The key analysis parameters are the cutout location and its size. The effect of out-of-plane bending and horizontal shear are also examined in the stability analysis.

• The Journal of Advanced Prosthodontics
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• v.8 no.2
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• pp.125-130
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• 2016

PURPOSE. The purpose of this study was to determine the effect of changes in the horizontal plane angle on the mesiodistal width ratios of the maxillary anterior teeth during the acquisition of frontal view photographs, derive these ratios for Korean adults on the basis of the data obtained, and analyze them using the Golden Proportion as a reference. MATERIALS AND METHODS. In experiment I, 30 plaster casts were mounted on an articulator and positioned on the angle-measuring device with a center setting of $0^{\circ}$. The device was rotated to $10^{\circ}$ in $1^{\circ}$ increments in a counterclockwise direction. At each angle, photographs were obtained and analyzed. Experiment II was based on 60 patients who visited the Department of Prosthodontics at Kyungpook National University Dental Hospital from February 2012 to February 2015. The patients were divided into three groups [Male (M), Female (F), Total (M + F)]. Frontal views were obtained for all groups and analyzed. RESULTS. From $1^{\circ}$ to $10^{\circ}$, the relative mesiodistal width ratios for the maxillary anterior teeth showed no significant differences from those at $0^{\circ}$. In all three groups, the relative width ratio of the maxillary central incisor was smaller than that specified in the Golden Proportion; the opposite was true for the canine. CONCLUSION. Our results suggest that the mesiodistal width ratios of the maxillary anterior teeth do not follow the Golden Proportion in Korean adults, and that a change in the horizontal plane angle from $1^{\circ}$ to $10^{\circ}$ during frontal photography does not affect these ratios.

• Journal of the Society of Naval Architects of Korea
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• v.54 no.6
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• pp.515-521
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• 2017

Large Cavitation Tunnel (LCT) of KRISO enables us to conduct cavitation tests of the propeller attached to a ship model. As the ship model tests are done at rather high Reynolds number of 107~108, flow measurement system such as pitot tube cannot be employed because of structural safety problems in its system and difficulties in installing it within the test section. Thus, KRISO has developed new 3-D LDV system used in large test section of LCT. There are several difficulties in using 3-D LDV, which did not allow efficient operation of it. The first trouble was the calibration using the conventional pin hole. To make the focus with same laser-beam waists at the wanted position, the high spatial resolution CCD is utilized in the calibration procedure for 3-D LDV. The off-axis configuration provides two velocity components in the horizontal plane and on-axis configuration gives third velocity component in the vertical plane. The horizontal velocity components are also obtained in the coincidence mode, which prevents any misleading results in the off-axis configuration. The nominal wake of Aframax tanker model is measured by the developed 3-D LDV system. The measured hull wake showed good agreement with that obtained by CFD calculation.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.4
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• pp.252-259
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• 2012

Purpose: This study evaluated the postoperative stability of counter clockwise rotation of the mandibular plane in anterior openbite patients, who have had one jaw surgery performed. Methods: This study includes patients with skeletal class III malocclusion accompanied by anterior openbite among the patients who have had BSSRO performed, resulting in counter clockwise rotation of the mandibule. We excluded the patients with genioplasty and segmental surgery, and included 23 patients who underwent BSSRO. Results: We found no statistical significance between the amount of counter clockwise rotation in the mandible in the Pearson correlation test. Also, there was no significant difference between Group 1 (< $3^{\circ}$) and Group 2 (> $3^{\circ}$). Conclusion: This study evaluated the amount of horizontal relapse, and the degree of relapse. Stable results were obtained. Although there was no statistical significance between the degree of openbite and the amount of horizontal relapse, the group with a greater amount of openbite had a greater amount of relapse.

• The Journal of Engineering Geology
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• v.14 no.4 s.41
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• pp.429-442
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• 2004

Landslide of the Whanpyeong Mountain which was occurred at Busan Metropolitan City in 1999 belongs to the category of plane failure. Automatic monitoring system to measure horizontal displacement, pore pressure change and load change has operating from reconstruction stage for evaluating rock slope stability (August, 2000$\~$Feburuary, 2002). As a result of the analysis on the monitoring performance data, it is suggested that infiltrated rain water from pound surface discharges rapidly through cut-slope because pressure head of water decreases rapidly after rainfall while rise of pore pressure is proportional to the amount of rain water. As a result of data analyses for inclinometers and load cells, it seems that slope is stablized be cause ground deformation is rarely detected. The areas especially similar to the study site where landslide is induced by heavy rain fall, change of pore pressure is rapidly analyzed using automatic monitoring system. Therefore, it is considered that automatic monitoring system is very effect for slope stability analysis on important cut-slopes.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.3
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• pp.255-261
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• 2007

Preface: Dental implant is important method that may solve the mastication, occlusion, esthetic, temporomandibular joint, and psychologic problem in oral and maxillofacial surgery. It is ideal that all of the implant are well positioned by adequate technique. By the way it‘s not always possible because of some anatomic, physiologic factor. In this case, If the implant can be moved to adequate position, it may be possible more esthetically and implanted patients more satisfied, but the majority of Implantists and orthodontists have thought that it is not possible. However, Implant, in fact, can be moved. and thus we can overcome the limit of implantation more. The aim of the present study was to evaluate the possibility of implant movement after corticotomy. Case report: Patient missed the upper right first molar. and implantation was done after completion of socket healing. We wait six months for osseointegration. Then, corticotomy was done under local anesthesia and close coil was used for orthodontic force. After traction during 3 weeks, we find the change of implant position at horizontal plane. we can not see the degenerative change on adjacent structure and tracted implant. there is a clinical mobility on upper right second premolar that used for anchorage but it subside spontaneously at the timing of prosthetic restoration without additional treatment. Discussion: As we could have some knowledge with this experiment, we report the case of implant movement after corticotomy and suggest a method about more esthetic implant treatment with a review of literature.

• The korean journal of orthodontics
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• v.45 no.5
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• pp.236-244
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• 2015

Objective: The aim of this study was to investigate three-dimensional molar displacement after distalization via miniscrews and a horizontal modification of the trans-palatal-arch (TPA). Methods: The subjects in this clinical trial were 26 Class II patients. After the preparation of a complete set of diagnostic records, miniscrews were inserted between the maxillary 2nd premolar and 1st molar on the palatal side. Elastic modules connected to the TPA exerting an average force of 150-200 g/side parallel to the occlusal plane were applied. Cone-beam computed tomography was utilized to evaluate the position of the miniscrews relative to the adjacent teeth and maxillary sinus, and the direction of force relative to molar furcation. The distances from the central point of the incisive papilla to the mesiopalatal cusps of the 1st maxillary molars and the distances between the mesiopalatal cusps of the left and right molars were measured to evaluate displacement of the maxillary molars on the horizontal plane. Interocclusal space was used to evaluate vertical changes. Results: Mean maxillary 1st molar distalization was $2.3{\pm}1.1mm$, at a rate of $0.4{\pm}0.2mm/month$, and rotation was not significant. Intermolar width increased by $2.9{\pm}1.8mm$. Molars were intruded relative to the neighboring teeth, from 0.1 to 0.8 mm. Conclusions: Distalization of molars was possible without extrusion, using the appliance investigated. The intrusive component of force reduced the rate of distal movement.

• The korean journal of orthodontics
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• v.48 no.3
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• pp.143-152
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• 2018

Objective: This study examined cone-beam computed tomography (CBCT)-derived multiplanar-reconstructed (MPR) cross-sections to clarify the salient characteristics of patients with skeletal class III malocclusion with midface deficiency (MD). Methods: The horizontal and sagittal plane intersection points were identified for middle-third facial analysis in 40 patients in the MD or normal (N) groups. MPR images acquired parallel to each horizontal plane were used for length and angular measurements. Results: A comparison of the MD and N groups revealed significant differences in the zygoma prominence among female patients. The convex zygomatic area in the N group was larger than that in the MD group, and the inferior part of the midface in the N group was smaller than that in the MD group for both male and female patients. A significant difference was observed in the concave middle maxillary area among male patients. Conclusions: This study was conducted to demonstrate the difference between MD and normal face through MPR images derived from CBCT. Male patients in the MD group had a more flattened face than did those in the N group. Female patients in the MD group showed a concave-shaped lower section of the zygoma, which tended to have more severe MD. These findings indicate that orthognathic surgery to improve skeletal discrepancy requires different approaches in male and female patients.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.21 no.4
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• pp.345-352
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• 1999

This study was conducted for the purpose of suggestion of the new technique of sagittal split ramus osteotomy pararell to the true sagittal plane. This pararellism is the important concept of the sagittal split ramus osteotomy to reduce the condylar sagging including mandibular hypomobility, temporomandibular disorder, occlusal relapse and other complications. We used 26 adult dry manibles(52 rami), and obtained the computed tomographs through the sagittal, horizontal and coronal sections. The results were obtained as follows. 1. On sagittal section, mean area of S1 was $8.63{\pm}2.10cm^2$, S2 was $8.93{\pm}1.94cm^2$, S3 was $9.49{\pm}2.15cm^2$, S6 was $10.72{\pm}2.22cm^2$. The wider area of sagittal section, the more lateral section, But, no significant differency between the areas of the sagittal sections(P>0.05). 2. On horizontal section, The distance between the inferior alveolar canal and the lateral cortical plate of the mandibular ramus were $6.73{\pm}1.24mm$ minum, $7.70{\pm}1.44mm$ maximum. 3. On coronal section, Outer mandibular angle were $4.84{\pm}2.37^{\circ}$ right side, $4.93{\pm}2.12^{\circ}$ left side. 4. The design of the ideal true sagittal split ramus osteotomy is that posterior border of osteotomy must be limited vertically, at the right posterior point of lingula mandibularis and anterior of osteotomy must be extended to mandibular body, anteroinferiorly.

• Korean Journal of Applied Biomechanics
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• v.17 no.3
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• pp.181-188
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• 2007

The purpose of this study was to investigate the biomechanical effects of wearing different type of insole shoes on gait characteristics in patients with knee osteoarthritis. Seven patients with knee osteoarthritis (Grade 3 & 4 by Kellgren & Lawrence) were participated in the study. They wore two different type of shoes (with Gel-type Insole: GIS, with Normal insole: NIS) during gait. Three dimensional cinematography and Ground Reaction Force(GRF) data were used to get the maximal value of horizontal distance between the center of pressure in GRF and knee joint center, GRF in mediolateral direction, peak value of GRF in frontal plane, vertical compressive force and adduction moment in knee joint. The results were as follows: The maximal value of horizontal distance between the center of pressure in GRF and knee joint center was smaller in GIS than NIS. The peak value of GRF in mediolateral direction was found in 30% of gait cycle, five subjects wearing GIS showed lower value of peak GRF in mediolateral direction than wearing NIS. The peak value of GRF in frontal plane and vertical compressive force in knee joint did not show any difference between GIS and NIS. The adduction moment in GIS decreased in the late stance of gait and the mean value of the adduction moment in GIS smaller than that in NIS. GIS may help to move quickly knee joint center to the center of pressure in GRF, therefore it may prevent increasing the adduction moment in knee joint.