• Magazine of the Korea Concrete Institute
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• v.6 no.2
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• pp.180-187
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• 1994

Sixteen reinforced concrete beams were tested statically up to failure to investigate the arch action. Major variables were the shear span to depth ratio, steel ratio and existence of stirrups.The arch action in reinforced concrete beams started when flexural cracks appeared at the center of the span. Due to the reduction of internal moment arm length by the development of arch action, the measured steel tension was significantly higher than the calculated. As the shear span to depth ratio arid steel ratio decrease, the arch action in reinforced concrete eams increases. Over the entire length the force in the steel of no web reinforced beams having smaller a /d ratio than 3 was constant because the beams acted as a tied arch.

• Journal of Korean Neurosurgical Society
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• v.46 no.6
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• pp.522-527
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• 2009

Objective : Atlantal arch defects are rare. Few cadaveric and imaging studies have been reported on the variations of such anomalies. Our goal in this study was to examine the incidence and review the clinical implications of this anomaly. Methods : A retrospective review of 1,153 neck or cervical spine computed tomography (CT) scans was performed to identify patients with atlantal arch defects. Neck CT scans were performed in 650 patients and cervical spine CT scans were performed in 503 patients. Posterior arch defects of the atlas were grouped in accordance with the classification of Currarino et al. In patients exhibiting this anomaly, special attention was given to defining associated anomalies and neurological findings. Results : Atlantal arch defects were found in 11 (11/1153, 0.95%) of the 1,153 patients. The type A posterior arch defect was found in nine patients and the type B posterior arch defect was found in two patients. No type C, D, or E defects were observed. One patient with a type A posterior arch defect had an anterior atlantal-arch midline cleft (1/1153, 0.087%). Associated cervical spine anomalies observed included one $C_{6-7}$ fusion and two atlantal assimilations. None of the reviewed patients had neurological deficits because of atlantal arch anomalies. Conclusion : Most congenital anomalies of the atlantal arch are found incidentally during investigation of neck mass, neck pain, radiculopathy, and after trauma.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.547-548
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• 2011

• Journal of Chest Surgery
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• v.57 no.1
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• pp.99-102
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• 2024

This article presents a straightforward hybrid arch technique for treating residual type B aortic dissecting aneurysms following type A repair (replacement of the ascending aorta) that employs a frozen elephant trunk (FET) straight vascular prosthesis. The debranch-first method involves only cutting and sewing the previous ascending graft, inserting the FET from zone 0, and debranching the arch vessels using a trifurcated graft. This technique is less invasive as it eliminates the need to manipulate the dissected distal arch aneurysm. We successfully applied this technique to 3 patients, with no instances of in-hospital death, stroke, or paraplegia. The debranch-first technique, combined with zone-0 FET insertion, simplifies the redo repair of residual type B aortic dissection.

• Structural Engineering and Mechanics
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• v.27 no.6
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• pp.639-650
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• 2007

Applying the method calculating creep of Concrete Filled steel Tube (CFT) members based on the Elastic Continuation and Plastic Flow theory for concrete creep with the finite element method, the paper develops a new numerical method for the creep of CFT arch bridges considering effects of bending moment. It is shown that the method is feasible and reasonable through comparing the predicted stresses and deflection caused by the creep with the results obtained by the method of Gu et al. (2001) based on ACI209R model and experimental data of an actual CFT arch bridge. Furthermore, nine CFT arch bridges with different types are calculated and analyzed with and without the effects of bending moment. As a result, the bending moment has considerable influences on long-term deformations and internal forces of CFT arch bridges, especially when the section of arch rib is subjected to a large bending moment.

• The korean journal of orthodontics
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• v.41 no.4
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• pp.224-236
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• 2011

Objective: The purpose of this study was to analyze the dental and basal arch forms in patients with normal occlusion using the computed tomography (CT) imaging method. Methods: CT images were taken from 27 normal occlusion subjects (male, 15; female, 12) and these images were reconstructed into three-dimensional models. A 3D-coordinate system was formed by setting the middle of the facial axis (FA) point of the maxillary central incisors as the origin. The morphology of the maxilla and mandibular dental and basal arches were analyzed by sectioning parallel to the maxillary occlusal plane. Results: There was no significant difference between A point and B point and between the maxillary 1st molars in both sides of the maxillary and mandibular basal bone. The dental arch was located more labially than the basal arch in the anterior portion. The bucco-lingual crossover of the dental arch and basal arch was formed at the molar region in the maxilla, and at the premolar region in the mandible. Conclusions: This study will help provide three-dimensional diagnostic information about the relationship between basal and dental arches in patients who have severe dental compensation and inappropriate jaw relationships.

• Structural Engineering and Mechanics
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• v.37 no.3
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• pp.321-330
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• 2011

Long-term properties of concrete affect structures in many respects, not excepting dynamic behaviors. This paper investigates the influence of concrete creep on the dynamic behaviors of concrete filled steel tube (CFT) arch bridges, by means of combining the analytical method for the creep of axially compressed CFT members, which is based on Model B3 for concrete creep, with the finite element model of CFT arch bridges. By this approach, the changes of the stress and strain of each element in the bridge with time can be obtained and then transformed into damping and stiffness matrices in the dynamic equation involved in the finite element model at different times. A numerical example of a long-span half-through CFT arch bridge shows that creep influences the natural vibration characteristics and seismic responses of the bridge considerably, especially in the early age. In addition, parameter analysis demonstrates that concrete composition, compressive strength and steel ratio have an obvious effect on the seismic response of the CFT arch bridge.

• The korean journal of orthodontics
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• v.17 no.2
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• pp.289-297
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• 1987

For the comparisons of dental archs and crowdings between musical wind instrument players groups and non-wind instrument players groups, 64 male wind instrument players and 31 non-wind instrument players group were selected. The results of the measurements were as follow. 1 Upper intercanine widths, upper basal arch widths, lower basal arch widths were statistically significant between musical wind instrument players groups (Class A, Class B) and non-wind musical instrument players group. 2 The mean value of upper intercanine width m Class A ($373{\pm}2.3mm$) was greater than than in Class B ($362{\pm}17mm$) and non-wind musical instrument players group($360{\pm}16mm$) 3 The mean value of lower basal arch width m Class B ($422{\pm}25mm$) was greater than that in non wind instrument players group ($395{\pm}28mm$). 4 The differences in the mean values of crowdings between Class A and Class Band non-wind instrument players group were not statistically significant.

• Journal of Korean Society of Rural Planning
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• v.18 no.3
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• pp.57-65
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• 2012

This research is focus on the analysis of bridge image and preference. In this study, 3 types of bridge with arch bridge, cable stayed bridge, and suspension bridge, 4 prospect points named A, B, C, and D will be simulated in one scene for final analysis of bridge image and preference.On prospect point A, higher evaluation is received among the arch bridge. In addition, for cable stayed bridge and suspension bridge, the Higher evaluation is received among the most at the arch bridge on prospect point B. At the on prospect point C, higher evaluation is received among the most cable stayed bridge and suspension bridge compared with arch bridge. At the on prospect point D, lower evaluation is received among the cable stayed bridge and suspension bridge compared with arch bridge. The highest average total preference is received for cable stayed bridge. And, The lowest average total preference is received for arch bridge. Cable stayed bridge is suitable for the Baegya Bridge than arch bridge in the Landscape point. In conclusion, the preference for one bridge is not the same at different prospect points through above research.

• The korean journal of orthodontics
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• v.13 no.1
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• pp.105-114
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• 1983

the author studied the corelativity between the head and face and the maxillary arch in Korean. This study was undertaker in 336 persons at age from 9 to 19 years who had normal occlusion by means of angle's classification. The following results were obtained. 1. The corelative coefficient between the Height of Head and Face (H.H.F.) and the Arch Length (A.L.) was 0.203-0.543, 2. The corelative coefficient between the Bizygomatic width (Z.W.) and the Bicanine width (C-C) was 0.203-0.543. 3. The corelative coefficient between the Bizygomatic width (Z.W.) and the Bimolar width (M-M) was 0.206-0.600. 4. The corelative coefficient between the Face shape (Index a) and Maxillaxy arch shape (In-dex c) was 0.232-0.404. 5. The corelative coefficient between the Face shape (Index a) and Maxillary arch shape (Index d) was 0.221-0.401. 6. There was no corelativity between the Anterior-posterior width of head (A.P.W.) and Arch Length A.L.), Head shape (Index b) and Maxillary arch shape (Index c, Index d).