• 대한기계학회논문집
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• 제14권3호
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• pp.624-635
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• 1990

본 연구에서는 마멸과정을 선형파괴역학적 관점에서 해석하여, 탄성체의 표면 에 산재되어 있는 표면균열의 전파거동을 마멸과정규명의 입장에서 살펴보고자 한다. 우선 마멸거동에 관한 파괴역학적 접근방식에 의한 마멸이론의 확립을 위해서, 표면균 열이 내부균열보다 그 전파 가능성이 높다고 한 Keer등의 주장에 착안하여 Hertz 접촉 압력하의 경사진 표면균열의 전파거동을 선형파괴역학적으로 해석하고자 한다. 이론 해석에 있어서는 표면균열을 인상전립의 연속분포로 치환하고, 전립밀도분포함수에 관 한 특이적분방정식을 유도해서 Erdogangupta의 방법을 이용하여 그 해를 구하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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• pp.1619-1620
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• 2006

This paper deals with a new two dimensional clinometer based on dual axis micromachined accelerometers. The clinometer is a small and low-cost product, which is mainly developed to help golfers read easily the tilt of a putting green. First, this paper proposes the principle of two dimensional clinometer and also a calibration method to improve accuracy with respect to the offset voltage and sensitivity of a accelerometer. Experimental results show that the proposed clinometer can provide useful information on the tilt of an inclined plane.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2010년도 추계학술대회
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• pp.40-43
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• 2010

This paper deals with a new two dimensional clinometer based on dual axis micromachined accelerometers. The clinometer is a small and low-cost product, which is mainly developed to help golfers read easily the tilt of a putting green. First, this paper proposes the principle of two dimensional clinometer and also a calibration method with respect to the offset voltage and sensitivity of a accelerometer. Experimental results on the developed clinometer show that the proposed clinometer can provide useful information on the tilt angle and direction of an inclined plane.

• 대한치과교정학회지
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• 제22권1호
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• pp.169-177
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• 1992

This investigation was carried out in order to find out changes in head postures and in craniofacial morphology, in relation to the inclination of cervical column. For this study 85 subjects, consisting 39 males and 49 females, between the ages of 7 to 24 years old were chosen, and following results were observed after analysing the correlation coefficients between each structures. 1. No definite relationships were observed between the inclination of cervical column (CVT/HOR) and the inclination of anterior cranial base (SN/VER) 2. No definite relationships were observed between the inclination of mandibular ramus (RL/HOR) and the inclination of mandibular inclination (MLP/VER). 3. In subjects with anteriorly inclined cervical column, increase in mandibular plane inclinations (ML/VER) were observed. 4. No definite relationships were observed between the inclination of cervical column (CVT/HOR) and changes in palatal plane (NL/VER).

• 천문학회보
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• 제39권1호
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• pp.56.1-56.1
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• 2014

With the advent of high-resolution high-sensitivity observations, spiral patterns have been revealed around several asymptotic giant branch (AGB) stars. Such patterns can provide possible evidence for the existence of central binary stars embedded in outflowing circumstellar envelopes. It is, however, not generally recognized that the binary induced pattern, vertically extended from the orbital plane, exhibits a ring-like pattern with an inclined viewing angle. I will first review the binary-induced spiral-shell patterns on the AGB circumstellar envelopes with the effect of inclination angle with respect to the orbital plane, of which large inclination cases reveal incomplete ring-like patterns. I will describe a method of extracting such spiral-shell from the gas kinematics of an incomplete ring-like pattern to place constraints on the characteristics of the (unknown) central binary stars. This first success may open the possibility of connecting the ring-like patterns commonly found in the AGB circumstellar envelopes and in the outer parts of (pre-)planetary nebulae and pointing to the conceivable presence of central binary systems, which may give a clue for the onset of asymmetrical planetary nebulae.

• 대한소아치과학회지
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• 제7권1호
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• pp.33-40
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• 1980

The author observed the eruption pattern of the mandibular premolars. For this study the author took 406 cases of oblique cephalographs of 6 to 12 year old children. The measurement were with regard to the vertical and horizontal dimensional changes and tooth axis changes to the occlusal plane. The following results were obtained. 1. At stage V the tooth axis of 1st premolar inclined mesially to the occlusal plane, as the tooth erupt toward vertically the angulation changed that at stage X the tooth axis almost right angle to the occlusal plane. 2. The distance from the root apex of premolars to the lower border of mandible were slightly increased to the stage VII, while after stage VII rapid increasing appeared. At stage X the distance of 1st premolar was more longer than 2nd premolar. 3. The distance from the mesial surface of 1st molar to the mesial surface of premolars were decreased slightly to the stage VII, but this distances were decreased rapidly after stage VII. 4. The distance between distal surface of 1st premolar and mesial surface of 2nd premolar was almost constant before stage VIII, at stage IX this distance was little presented because the premolars were contacted.

• Journal of Welding and Joining
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• 제21권6호
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• pp.77-83
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• 2003

The finite element analysis was performed for the cracks existing in residual stress fields in order to investigate the effects of configuration of residual stress distribution to the fatigue crack opening behaviour. And the variation of stress distributions adjacent to the crack caused by uploading was examined. The finite element model with contact elements for the crack plane and plane stress elements for the base material and the analytical method based on the superposition principle to estimate crack opening behaviour and the stress distribution adjacent to the crack subjected to uploading were used. The results of the analysis showed that crack opening behaviors and variations of stress distribution caused by uploading were changed depending on the configuration of residual stress distribution. When the crack existed in the region of compressive residual stress and the configuration of compressive residual stress distribution were inclined, a partial crack opening just behind of a crack tip occurred during uploading. Based on the above results, it was clarified that the crack opening behaviour in the residual stress field could be predicted accurately by the finite element analysis using these analytical method and model.

• 대한기계학회논문집
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• 제13권2호
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• pp.243-251
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• 1989

본 연구에서는 균질재료에 대하여 Vitec, Riedel, Yokobori와 Kamei 등이 사용되었던 모델을 계면균열문제에 도입하였다. 즉, 균열선단에 기울어진 슬립면 (Slip plane)을 가정하고 소성역이 이 슬립면 상에 존재한다고 가정하여 이 모델에 모우드 III의 응력이 작용하는 경우에 대하여 해석하였다.소성여과 균열을 전위 (dislocation)의 연속된 분포로 나타내고 평형조건을 만족하는 전위밀도함수(disl- ocation density function)를 구하였다.이러한 모델의 해석을 통하여 각 재료에서의 의 마찰전단응력의 변화에 따른 소성역의 크기 및 균열선단에서의 상대변위의 변화를 살펴보았다. 또한 이러한 소성역을 가정한 경우의 J-적분과 균열선단에서의 상대 변위와의 관계에 대해서도 살펴보았다.

• Structural Engineering and Mechanics
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• 제81권5호
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• pp.591-606
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• 2022

When the friction pendulum system and shear keys work together to resist the ground motion, which inclined inputs (non 45°) to the bridge structure, the shear keys in XY direction will be sheared asynchronously, endowed the friction pendulum system with a violent curvilinear motion on the sliding surface during earthquakes. In view of this situation, firstly, this paper abandons the equivalent linearization model of friction and constructs a Spring-Coulomb friction plane isolation system with XY shear keys, and then makes a detailed mechanical analysis of the movement process of friction pendulum system, next, this paper establishes the mathematical model of structural time history response calculation by using the step-by-step integration method, finally, it compiles the corresponding computer program to realize the numerical calculation. The results show that the calculation method in this paper takes advantage of the characteristic that the friction force is always µmg, and creatively uses the "circle making method" to express the change process of the friction force and resultant force of the friction pendulum system in any calculation time step, which can effectively solve the temporal nonlinear action of the plane friction; Compared with the response obtained by the calculation method in this paper, the peak values of acceleration response and displacement response calculated by the unidirectional calculation model, which used in the traditional research of the friction pendulum system, are smaller, so the unidirectional calculation model is not safe.

• 대한치과보철학회지
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• 제14권1호
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• pp.55-65
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• 1976

The influences of the mandibular displacement and valium administration on the muscular activity were observed by spectrophotometric analysis of glycogen, glucose, G-6-P, lactate, pyruvate, ATP, phosphocreatine ana protein. Experimental animals were divided into three groups; the first was the mandibular displacement group, the second was valium administered group and the third was the mandibular displacement and valium admministered group. In mandibular displacement group, the high inclined plane with a gap of 2.5mm to 3.0mm between the upper and lower incisors was created by setting the silver crowns on the lower incisors. By creating such a high inclined plane, the bite was opened and the mandible was dispalced posteriorly. In valium administered group, 5mg/kg body weight of valium was administered intraperitoneally every day until the animal was sacrificed. Results were as follows: I) The body weight of all experimental rats was decreased in the beginning of experimental periods. The body weight of the mandibular displacement group showed the similar increasing rate as the control group from 15 days of experimental period. 2) The superficial masseter muscles of the mandibular displacement group appeared to be decreased it's functional activity at 36hrs, 60hrs and 96hrs of experimental periods as revealed by the decrease of various metabolites studied in this experiment. From 96hrs of experimental periods, the contents of those metabolites tended to increase up to the control level. 3) The superficial masseter muscle of 2nd group showed the decreased value of all metabolites at until 60hrs and the values were recovered to almost the same as the control at 168hrs. 4) Glycogen and G-6-P contents induced by mandibular displacement plus valium administration, showed longer duration of the decreased value than 1st group. And the decrease of glucose and pyruvate contents induced by mandibular displacement at 36hrs and 60hrs of experimental periods was enhanced by valium administration. However, the contents of lactate in 3rd group were decreased continuously until the end of experiment.