• Clinics in Shoulder and Elbow
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• 제2권1호
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• pp.8-13
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• 1999

The results of the operative treatment of the Grade III acromioclavicular joint injury is defined by the durability of the reduced joint and free of exertional pain. Several surgical techniques have been applied to reduce and stabilize the joints effectively. Resection of clavicular lateral end and subacromial decompression also could be applied to prevent post-operative arthritic change. Biomechanical studies reveals the role of clavicular elevation and rotation to achieve more than 90 degrees of elevation. It also serves as a attachment site of deltoid and trapezius muscle. The stability and mobility of the both acromioclavicular and coracoclavicular joint are important to get full functional recovery. We modified the methods of coracoacromial ligament transfer described by Weaver-Dunn and by Shoji et a!. to pre­vent pullout of the transferred ligament and to get more improved functional results. Main technical point was harvesting full thickness bone block and fix it through the key-hole to reduce pull out angle.

• 대한치과교정학회지
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• 제25권2호
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• pp.143-152
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• 1995

이 연구는 다양한 형태의 closing loops의 activation에 따른 치주조직에서의 응력분포를 평가하고 상악 절치의 이동 양상을 예측하기 위하여 3차원 유한요소법에 의하여 시행되었다. 동시에 상악 절치의 견인시 사용되는 bull loop, key-hole loop, T-loop, combination loop 그리고 asymmetrical T-loop도 3차원 유한요소법에 의해 분석 되었다. 이 연구로부터 얻어진 결과는 다음과 같다. 1. 여러가지 형태의 공간폐쇄용 루프중 bull loop에서 가장 큰 수평력을 나타냈으며 , key-hole, combination loop, T-loop 순이었다. 이들 모두 치아이동의 양상은 uncontrolled tipping을 나타냈다. 2. Asymmetrical TMA T-loop에서는 수평력이 현저히 감소하였으며, 절치부위에 함입력이 나타났다. 3. 절치부에서 torque의 증가에 따라 모멘트가 증가하였고, 선형적인 증가를 보였다. 4. 모멘트의 증가에 따라 치아의 초기 이동양상은 uncontrolled tipping에서 치근이동 양상으로 변화되었다.

• 대한기계학회논문집A
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• 제31권11호
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• pp.1053-1058
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• 2007

Micro-EDM technology (or the manufacture of miniature parts is used to make a micro hole. Two electrode shaping methods, mechanical electrode grinding and WEDG technique, have been studied. In this study, an electrode shaping method by using previously machined hole is introduced in order to obtain an optimal hole-making condition. Key factors such as applied voltage, capacitance, feedrate, and hole-dimension have an influence on the fabricating error of electrode shaping, which are taper ratio of a hole, electrode form accuracy, and electrode surface. Therefore, we try to investigate the optimal fabricating of electrode shaping from various experiments. Results from experiments, it was able to minimize the electrode fabricating error as voltage increases, and also applied feedrate and capacitance decreases.

• Geomechanics and Engineering
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• 제20권5호
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• pp.461-474
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• 2020

Analysing the incompatible deformation and damage evolution around the tunnels in mixed strata is significant for evaluating the tunnel stability, as well as the interaction between the support system and the surrounding rock mass. To investigate this issue, confined compression tests were conducted on upper-soft and lower-hard strata specimens containing a circular hole using a rock testing system, the physical mechanical properties were then investigated. Then, the incompatible deformation and failure modes of the specimens were analysed based on the digital speckle correlation method (DSCM) and Acoustic Emission (AE) data. Finally, numerical simulations were conducted to explore the damage evolution of the mixed strata. The results indicate that at low inclination angles, the deformation and v-shaped notches inside the hole are controlled by the structure plane. Progressive spalling failure occurs at the sidewalls along the structure plane in soft rock. But the transmission of the loading force between the soft rock and hard rock are different in local. At high inclination angles, v-shaped notches are approximately perpendicular to the structure plane, and the soft and hard rock bear common loads. Incompatible deformation between the soft rock and hard rock controls the failure process. At inclination angles of 0°, 30° and 90°, incompatible deformations are closely related to rock damage. At 60°, incompatible deformations and rock damage are discordant due that the soft rock and hard rock alternately bears the major loads during the failure process. The failure trend and modes of the numerical results agree very well with those observed in the experimental results. As the inclination angles increase, the proportion of the shear or tensile damage exhibits a nonlinear increase or decrease, suggesting that the inclination angle of mixed strata may promote shear damage and restrain tensile damage.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제6권10호
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• pp.2663-2678
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• 2012

Due to sharp depth transition, big holes may be found in the novel view that is synthesized by depth-image-based rendering (DIBR). A hole-filling method based on disparity map is proposed. One important aspect of the method is that the disparity map of destination image is used for hole-filling, instead of the depth image of reference image. Firstly, the big hole detection based on disparity map is conducted, and the start point and the end point of the hole are recorded. Then foreground pixels and background pixels are distinguished for hole-dilating according to disparity map, so that areas with matching errors can be determined and eliminated. In addition, parallaxes of pixels in the area with holes and matching errors are changed to new values. Finally, holes are filled with background pixels from reference image according to these new parallaxes. Experimental results show that the quality of the new view after hole-filling is quite well; and geometric distortions are avoided in destination image, in contrast to the virtual view generated by depth-smoothing methods and image inpainting methods. Moreover, this method is easy for hardware implementation.

• 한국자기학회지
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• 제26권4호
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• pp.119-123
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• 2016

Cu 원자 4개를 포함한 cubane 구조의 분자자성체의 전기구조 및 자기적 성질을 제1원리의 범밀도함수법을 이용하여 계산하였다. 계산 된 결과, Cu 원자는 +2가를 가지며, 팔면체 배위자중 면내 짧은 4개의 배위산소원자로 인해 3d $x^2-y^2$ hole 궤도를 가지고 있었다. 스핀배열에 따른 총 에너지 계산에서 면내는 반강자성, 면간은 강자성 자기구조가 가장 안정되었다. 교환상호작용 J의 크기는 면내의 J가 훨씬 크고 반강자성 성질을 나타내었으며, 나머지 면간의 J값은 아주 작았다. 이러한 원인은 Cu $x^2-y^2$ hole 궤도정렬로 인하여 면내 강한 초교환상호작용의 결과이다.

• 반도체디스플레이기술학회지
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• 제16권3호
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• pp.8-13
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• 2017

In this paper, the measurement of the inner diameter dimension of the circular hole by using a machine vision system was studied. This paper was focused on the theory and key technologies of machine vision inspection technology for the improvement of measurement accuracy and speed of the micro circular holes. A new method was proposed and was verified through the experiments on Gray conversion, binarization, edge extraction and Hough transform in machine vision system processes. Firstly, the Hough transform was proposed in order to improve the speed increase and implementation ease, it demonstrated the superiority of Hough transform and improvement through a comparative experiment. Secondly, we propose a calibration method of the system in order to obtain exactly the inner diameter of the circular hole. Finally, we demonstrate the reliability of the entire system as a MATLAB-based implementation of the GUI program, measuring the inner diameter of the circular hole through the circular holes of different dimensions measuring experiment.

• Structural Engineering and Mechanics
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• 제81권1호
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• pp.39-50
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• 2022

Layer separation (delamination) is an essential threat to fiber-reinforced polymer (FRP) plates under dynamic, static, and fatigue loads. Under compressive load, the growth of delamination will lead to structural instability. The aim of this paper is to present a method using shape memory alloy (SMA) stitches to suppress the delamination growth in a FRP plate and to improve the buckling behavior of the plate with a rectangular hole. The present paper is divided into two parts. Firstly, a closed-form (CF) formulation for evaluating the buckling load of the FRP plate is presented. Secondly, the finite element method (FEM) will be employed to calculate the buckling loads of the plates which serves to validate the results obtained from the closed-form method. The novelty of this work is the development of the closed-form solution using the p-Ritz energy approach regarding the stress-dependent phase transformation of SMA to trace the equilibrium path. For the FEM, the Lagoudas constitutive model of the SMA material is implemented in FORTRAN programming language using a user material subroutines (VUMAT). The model is simulated in ABAQUS/Explicit solver due to the nature of the loading type. The cohesive zone model (CZM) is applied to simulate the delamination growth.

• 센서학회지
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• 제27권1호
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• pp.55-58
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• 2018

Low-cost and large-scale fabrication method of nanohole array, which comprises nanoscale voids separated by a few tens to a few hundreds of nanometers, has opened up new possibilities in biomolecular sensing as well as novel frontier optical devices. One of the key aspects of the nanohole array research is how to control the hole size following each specific needs of the hole structure. Here, we report the extensive study on the fine control of the hole size within the range of 500-2500 nm via surface-catalyzed chemical deposition. The initial hole structures were prepared via conventional photo-lithography, and the hole size was decreased to a designed value through the surface-catalyzed chemical reduction of the gold ion on the predefined hole surfaces, by simple dipping of the hole array device into the aqueous solution of gold chloride and hydroxylamine. The final hole size was controlled by adjusting reaction time, and the optimal experimental condition was obtained by doing a series of characterization experiments. The characterization of size-controlled hole array was systematically examined on the image results of optical microscopy, field emission scanning electron microscopy(FESEM), atomic-force microscopy(AFM), and total internal reflection microscopy.

• Bulletin of the Korean Chemical Society
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• 제31권6호
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• pp.1649-1656
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• 2010

Internal reorganization energy due to the structural relaxation in hole or electron hopping mechanism is one of the measurements of key indices in designing an organic thin film transistor (OTFT) for flexible display devices. In this study, the reorganization energies of dicyanoanthracenes for the hole and electron transfer were estimated by adiabatic potential energy surface and normal mode analysis method in order to examine the effect on the energies for the positional variation of the cyano substituents in the anthracene as a protocol of acenes to design an organic field effect transistor. The reorganization energy for the hole transfer was reduced considerably upon cyanation of anthracene, especially at the 9,10-positions of anthracene, and the origin of the reduction was interpreted in terms of understanding the coupling of vibrational modes to the hole transfer.