• 대한치과교정학회지
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• 제45권1호
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• pp.20-28
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• 2015

Objective: The purpose of this study was to observe stress distribution and displacement patterns of the entire maxillary arch with regard to distalizing force vectors applied from interdental miniscrews. Methods: A standard three-dimensional finite element model was constructed to simulate the maxillary teeth, periodontal ligament, and alveolar process. The displacement of each tooth was calculated on x, y, and z axes, and the von Mises stress distribution was visualized using color-coded scales. Results: A single distalizing force at the archwire level induced lingual inclination of the anterior segment, and slight intrusive distal tipping of the posterior segment. In contrast, force at the high level of the retraction hook resulted in lingual root movement of the anterior segment, and extrusive distal translation of the posterior segment. As the force application point was located posteriorly along the archwire, the likelihood of extrusive lingual inclination of the anterior segment increased, and the vertical component of the force led to intrusion and buccal tipping of the posterior segment. Rotation of the occlusal plane was dependent on the relationship between the line of force and the possible center of resistance of the entire arch. Conclusions: Displacement of the entire arch may be dictated by a direct relationship between the center of resistance of the whole arch and the line of action generated between the miniscrews and force application points at the archwire, which makes the total arch movement highly predictable.

• 대한디지털의료영상학회논문지
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• 제16권1호
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• pp.7-11
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• 2014

The body to achieve an interaction that are connected to each other. Foot of which plays an important role in motor activity. Insole that has been recently used, have a dynamic functional elements. In particular, support of Arch plays a very important role in terms of a motor function of the human body as a whole. It is possible to predict the proper support Arch with insole, the overall structure of the body there can affect the balance. In this study, by applying the insole which supports the Longitudinal arch and Transverse arch, you are trying to assess the interaction of balance and the body's ability. To target the 20 there is no problem in the sense of balance, college student, and changes were observed by measuring the Center of Position area and distance through the Biorescue device worn before and after led by Arch support. As a result, I showed improved results significantly discount rate after wearing in the Center of Position area and distance to assess the balance ability. Therefore, the correction insole function is to support the Longitudinal arch and Transverse arch to an important role in the foot. It may be that it has a functional element for improving the balance of the function of preventing collapse of the arch during walking, to disperse the weight of the entire foot, us reduce fatigue in the end.

• 대한치과보철학회지
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• 제32권3호
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• pp.396-410
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• 1994

Ten subjects who were going to wear conventional complete dentures were selected for this study. Theree subjects were women and seven were men. The average age was 63.1 years(range : 44 to 76 years). With the Height tracer (extraoral tracing device) in place the subject was instructed to go through the entire range of mandibular movements. The extreme lateral pathway of the incisor point, the so-called Gothic arch, was thereby inscribed by the stylus on the tracing plate. The mandibular movements in this study were peformed voluntarily by the subject(self guided technique) and guided by the dentist(chin-point technique and bimanual technique). The Gothic arch tracings were analysed and the Gothic arch angles and eccentric movement distances were measured. The results were as follows : 1. The apex position of the Gothic arch tracings of mandibular movements in edentulous patients varied both anterioposteriorly and mediolaterally. 2. The Gothic arch tracing had some lateral deviation during protrusion. 3. The average Gothic arch tracing angle was $136.7{\pm}12.0^{\circ}$ by subjects self guided technique, $135.7{\pm}5.9^{\circ}$ by chin-point technique, $136.6{\pm}6.5^{\circ}$ by bimanual technique. But there were no statistical differences in the reliability among the three techniques. 4. The average mandibular eccentric movements were irregular and the mandibular eccentric movement distances varied with a wide range.

• Structural Engineering and Mechanics
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• 제85권5호
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• pp.665-677
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• 2023

In the present study, the limit point buckling and postbuckling behaviors of sinusoidal, shallow arches with pinned supports subjected to localized sinusoidal loading, based on the Euler-Bernoulli beam theory, are numerically analyzed. There are some studies on the buckling of sinusoidal shallow arches under the effect of sinusoidal loading. However, in these studies, the sinusoidal loading acts along the horizontal projection of the entire shallow arch. No study has been found in the relevant literature pertaining to the stability of the shallow arches subjected to various lengths of sinusoidal loading. Therefore, the purpose of this paper is to contribute to the literature by examining the effect of the length of the localized sinusoidal loading and the initial rise of the shallow arch on the limit point buckling and postbuckling behaviors. Equilibrium paths corresponding to certain values of the length of the localized sinusoidal loading and various values of the initial rise parameter are presented. It has been observed that the length of the sinusoidal loading and the initial rise parameter affects the transition from no buckling to limit point instability remarkably. The deformed configurations of the sinusoidal shallow arch under localized loading regarding buckling and postbuckling states are illustrated, as well. The effects of the length of the localized sinusoidal loading on the internal forces of the shallow arch are investigated during various stages of the loading.

• 콘크리트학회지
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• 제6권2호
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• pp.180-187
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• 1994

철근콘크리트보에서의 아취작용에 대한 현상을 파악하기 위해 전단지간 대 유효높이의 비 (a/b), 철근비, 전단철근의 유무등을 변수로 하여 총 16개의 시험체를 제작하여 실험하였다. 실험결과, 철근콘크리트보에서 아취현상은 최초로 보에 휨균열이 발생되면서 시작되고, 휨균열이 전단지간 중앙위치까지 발생되면 아취현상이 현저해져 보의 전체적 거동을 지배하는 것으로 나타났다. 철근콘크리트보의 전체적 거동이 아취작용에 이해 주로 지배되면, 전단지간내에서 측정된 철근인장력은 계산된 철근인장력보다 휠씬 크게 나타났다. 철근콘크리트보에서 아취현상은 지점쪽에 가까울수록, 철근비가 낮을수록 헌저하고, 전단보강을 함으로서 아취현상은 작아졌다. 철근콘크리트보에서 아취현상은 a/b가 작아질수록 증가되고, a/b가 3이하에서는 아취현상이 지배적이었다. 전단보강이 안된 a/b가 3이하의 보에서는 최종하중단계에서 타이드 아취현상이 현저하여 철근 길이\ulcorner향에 따른 철근인장력은 거의 동일한 값을 나타냈다.

• Structural Engineering and Mechanics
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• 제9권2호
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• pp.169-180
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• 2000

An optimization procedure has been prescribed for the minimum weight design of symmetrical parabolic arches subjected to arbitrary loading. The cross section is assumed to be a symmetrical box section with variable depth and flange areas. The webs are unstiffened and have constant thickness. The proposed sequential, iterative search technique determines the optimum geometrical configuration of the parabolic arch which includes the optimum depth profile and the optimum lengths and areas of the required flange plates corresponding to the prescribed number of curtailments. The study shows that the optimum value of rise to span ratio (h/L) of a parabolic arch is maximum at 0.41 for uniformly distributed loading over the entire span. For any other loading, the optimum value of h/L is less than 0.41.

• 대한치과교정학회지
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• 제49권3호
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• pp.194-201
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• 2019

When a patient shows severe crowding, premolar extraction should be considered to provide required available space for alignment. If the third molars have already erupted and demonstrate a poor prognosis, third molar extraction and distalization of the posterior dentition can be used instead of premolar extraction to obtain space. Interproximal stripping (IPS) may also be used to gain space in cases of crowding. This case report describes the treatment of a 25-year-old man with severe crowding and mild lip protrusion. Although the crowding in the lower arch was severe enough to require first premolar extraction, distalization of the entire lower dentition with orthodontic mini-implants, extraction of the lower third molars, and IPS could successfully resolve the crowding and lip protrusion.

• 대한치과교정학회지
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• 제43권3호
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• pp.147-158
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• 2013

This article describes the orthodontic treatment of a 31-year-old Korean female patient with gummy smile and crowding. The patient showed excessive gingival display in both the anterior and posterior areas and a large difference in gingival heights between the anterior and posterior teeth in the maxilla. To correct the gummy smile, we elected to intrude the entire maxillary dentition instead of focusing only on the maxillary anterior teeth. Alignment and leveling were performed, and a midpalatal absolute anchorage system as well as a modified lingual arch was designed to achieve posterosuperior movement of the entire upper dentition. The active treatment period was 18 months. The gummy smile and crowding were corrected, and the results were stable at 21 months post-treatment.

• Journal of Chest Surgery
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• 제11권1호
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• pp.81-84
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• 1978

A 15 years Old girl was admitted with chief complaints of intermittent claudication of lower extremity, dizziness, and headache for 5 years. On admission, malignant hypertension was noted in the upper part of body [190-150/120-110] but femoral & dorsalis pedis pulse could not palpate. Once she had experienced C. V. A. due to hypertension of upper part, about years ago. On auscultation, systolic murmur was audible along the left sternal border. E.C.G. Showed left ventricular hypertrophy pattern, and others within normal limit. Retrograde aortography demonstrated diffuse narrowing of entire thoracic aorta with underdeveloped lower abdominal aorta [below the renal artery] & both common lilac artery, and rich collaterals, but normally visualized greater arteries in the aortic arch. On left posterolasteral thoracotomy, entire descending thoracic aorta revealed marked narrowing with mild perivascular adhesion, but no mediastinal pleura adhesion. These findings suggest as congenital type of atypical coarctation in the entire thoracic aorta with mild secondary change. But histopathology was showed the findings of chronic non-specific aortitis, later. Dacron by pass graft was performed with end to side anastomosis between graft and aortic wall. After operation, all her preoperative symptoms & signs were disappeared, and discharged with good general condition.

• 한국해양공학회지
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• 제23권1호
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• pp.96-103
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• 2009

In 2006, Jeju Island in South Korea experienced a crisis, no electricity for three hours anywhere in the entire island. This incident was caused by a domino effect that occurred after one of the submarine power cables connecting the island to Haenam, a coastal city on the mainland, was damaged by an external load, probably from a ship anchor or a steel pile being used in marine farming. This study presents a collision analysis of a new submarine power cable protector called arch type reinforced concrete. For the analysis, a dynamic finite element program, ANSYS AUTODYN, was used to examine the displacement and stress of the submarine power cable protector using different material models (RHT concrete model, Mohr.Coulomb concrete model). In addition, two reinforcing bar spacings, 75 mm and 150 mm, were considered. From the analyses, the effects of the parameters (concrete model and spacing) on the results (displacement and stress) were analyzed, and the relations between the damage and parameters were found.