• Steel and Composite Structures
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• 제34권2호
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• pp.227-239
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• 2020

The aim of this study is to obtain the nonlinear and post-buckling responses of relatively thick functionally graded plates with oblique elliptical cutouts using a new semi-analytical approach. To model the oblique elliptical hole in a FGM plate, six plate-elements are used and the connection between these elements is provided by the well-known Penalty method. Therefore, the semi-analytical technique used in this paper is known as the plate assembly technique. In order to take into account for functionality of the material in a perforated plate, the volume fraction of the material constituents follows a simple power law distribution. Since the FGM perforated plates are relatively thick in this research, the structural model is assumed to be the first order shear deformation theory and Von-Karman's assumptions are used to incorporate geometric nonlinearity. The equilibrium equations for FGM plates containing elliptical holes are obtained by the principle of minimum of total potential energy. The obtained nonlinear equilibrium equations are solved numerically using the quadratic extrapolation technique. Various sets of boundary conditions for FGM plates and different cutout sizes and orientations are assumed here and their effects on nonlinear response of plates under compressive loads are examined.

• Advances in nano research
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• 제7권5호
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• pp.311-324
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• 2019

The present study aims to evaluate the nonlinear and post-buckling behaviors of orthotropic graphene sheets exposed to end-shortening strain by implementing a semi-Galerkin technique, as a new approach. The nano-sheets are regarded to be on elastic foundations and different out-of-plane boundary conditions are considered for graphene sheets. In addition, nonlocal elasticity theory is employed to achieve the post-buckling behavior related to the nano-sheets. In the present study, first, out-of-plane deflection function is considered as the only displacement field in the proposed technique, which is hypothesized by an appropriate deflected form. Then, the exact nonlocal stress function is calculated through a complete solution of the von-Karman compatibility equation. In the next step, Galerkin's method is used to solve the unknown parameters considered in the proposed technique. In addition, three different scenarios, which are significantly different with respect to concept, are used to satisfy the natural in-plane boundary conditions and completely attain the stress function. Finally, the post-buckling behavior of thin graphene sheets are evaluated for all three different scenarios, and the impacts of boundary conditions, polymer substrate, and nonlocal parameter are examined in each scenario.

• 전자공학회논문지
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• 제50권1호
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• pp.131-136
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• 2013

칩 적층기술의 발달로 TSV(Through Silicon Via) 기반 3D IC가 개발되었다. 3D IC의 높은 신뢰성과 수율을 얻기 위해서는 pre-bond 와 post-bond 수준에서 다양한 TSV 테스트가 필수적이다. 본 논문에서는 pre-bond 다이의 TSV 연결부에서 발생하는 미세한 고장과 post-bond 적층된 3D IC의 TSV 연결선에서 발생하는 다양한 고장을 테스트할 수 있는 설계기술을 소개한다. IEEE 1500 표준 기반의 래퍼셀을 보완하여 TSV 기반 3D IC pre-bond 및 post-bond의 at speed test를 통하여 known-good-die와 무결점의 3D IC를 제작하고자 한다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2021년도 학술발표회
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• pp.154-154
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• 2021

Since the development of Bubble Image Velocimetry (BIV) technique as the complementary technique of Particle Image Velocimetry (PIV), the application of digital imaging technique in the field of hydraulic and coastal engineering increased rapidly. BIV works very well in multi-phase flow (air-water) flows where the PIV technique doesn't. However, the velocity field obtained from BIV technique often resulted in a velocity vector on the outside of the flow (false velocity) since the Field of View (FOV) usually not only cover the air-water flow but also the area outside the flow. In this study, a simple technique of post processing velocity field was developed. This technique works based on the average of the pixel value in the interrogation area. An image of multi-phase flow of wave overtopping was obtained through physical experiment using BIV technique. The velocity calculation was performed based on the similar method in PIV. A velocity masking technique developed in this study then applied to remove the false velocity vector. Result from non-masking, manually removed and auto removed false velocity vector were presented. The masking technique show a similar result as manually removed velocity vector. This method could apply in a large number of velocity field which is could increase the velocity map post-processing time.

• 한국디지털정책학회:학술대회논문집
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• 한국디지털정책학회 2007년도 춘계학술대회
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• pp.15-22
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• 2007

The Korea Post has become the first government management entity to introduce Six Sigma Management Innovation Movement, a private-sector management technique in August 2003, and has since then successfully improved the quality of postal services including efficiency through enhanced business processes and public services. In 2006, The Korea Post expanded the Six Sigma down to six subordinate organizations including the KOVIX, pursuing the innovation of the entire organization from the regional off ice to each post offices.

• 한국운동역학회지
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• 제28권2호
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• pp.69-78
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• 2018

Objective: The purpose of this study was to investigate the feasibility of a new vault technique through a kinematic comparison of the YANG Hak Seon and Yeo 2 vaults. Method: The photographic images of the YANG Hak Seon and Yeo 2 vaults were collected using a high-speed camera, and their kinematic characteristics were analyzed using three-dimensional image analysis. Results: During the post-flight phase of the Yeo 2 and YANG Hak Seon vaults, the time of flight, height of flight, and flight distance were similar. At the peak of the post-flight phase, the trunk rotation angle of the YANG Hak Seon vault rotated $457^{\circ}$ more than did the Yeo 2 vault. During the post-flight descending period, the twist velocity of the trunk was much faster with the YANG Hak Seon vault ($1,278^{\circ}/s$) than with the Yeo 2 vault ($1,016^{\circ}/s$). Conclusion: To succeed in the new technique, the average twist velocity during post-flight must be maintained at $1,058^{\circ}/s$ and the twist velocity must be increased from the ascending phase.

• The Journal of Asian Finance, Economics and Business
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• 제8권4호
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• pp.959-969
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• 2021

This study aims to develop new constructs and indicators for sharia destination image, and then examine its effects on perceived value, tourist satisfaction, and post-visit behaviour. Furthermore, it analyses the mediating role of perceived value and tourist satisfaction on relationship between sharia destination image and post-visit behaviour. The population were domestic and Malaysian Muslim tourists who visited Aceh during the study period. The sampling was carried out in two stages. The first stage involved selecting most visited districts. The second stage involved randomly selecting tourists who visit during the study period in the districts. Data was collected using a structured questionnaire with a Likert scale. Also, a total of 270 questionnaires were distributed to domestic and Malaysian tourists in Aceh. Cluster sampling was used to determine the sample area, and purposive sampling technique was used to determine the study sample. Furthermore, the data analysis technique is Structural Equation Modelling. The results showed that the sharia destination image has a significant effect on perceived value. Meanwhile, the perceived value significantly influenced tourist satisfaction and post-visit behaviour. In addition, the perceived value and tourist satisfaction can mediate the effects of sharia destination image, which has no direct effect on post-visit behaviour.

• 음성과학
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• 제9권3호
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• pp.77-86
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• 2002

The purpose of this study was to investigate the effects of Sea Dong-Il's technique on voice quality in patients with vocal nodules and phonasthenia (vocal fatigue). Ten patients (4 nodules and 6 vocal fatigue) participated in the study. Each subject was assessed acoustically (Fo, Jitter, Shimmer, NNE) in the first and last session. Dr. Speech (version 3.4, Tiger-DRS) was used to compare acoustic parameters of pre-and post-treatment. Sea Dong-Il's technique consisted of breathing exercise, relaxation exercise, and phonation exercise. The results were as follows: First, Sea Dong- Il's technique tended to be effective on improving voice quality in patients with phonasthenia and vocal nodules. Second, the nature of improvements were as follows: there was a significant difference between pre-and post-treatment in shimmer (p < .01) and NNE (p < .001), while there was no significant difference between pre-and post-treatment in Fo and Jitter. Finally, given the fact that the number of subjects was only 10, the jitter might have shown a significant difference if more subjects participated in the experiment.

• Restorative Dentistry and Endodontics
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• 제30권3호
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• pp.215-220
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• 2005

포스트가 축조된 치아를 재근관 치료하는 경우 성공적인 비외과적 재근관치료를 시행하기 위해서는 포스트 제거가 선행되어야 한다. 기존의 포스트를 제거하는 방법으로는 초음파기구, Ruddle post removal system, Eaggler post remover, Masserann kit을 이용하는 방법 등 여러 가지가 소개 되고 있으나 기존의 방법들은 각 기구에 맞게 코어를 삭제해야 하는 시간과 많은 노력이 요구되며 포스트 제거시 치아나 포스트의 파절이 유발되기도 한다 그러나 최근에는 기존의 방법과는 다른 ATD automatic bridge remover를 이용해 포스트를 제거하는 새로운 방법이 소개되고 있으며 코어에 구멍을 형성하는 시간만 소요되어 비교적 빨리 제거 할 수 있다는 장점을 가지고 있다. 따라서 본 증례에서는 ATD automatic bridge remover를 이용해 주조포스트를 제거하고 성공적으로 재근관치료를 시행한 증례에 대해서 보고하고자 한다.

• Advances in nano research
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• 제7권6호
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• pp.405-417
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• 2019

This research is devoted to study post-buckling analysis of functionally graded carbon nanotubes reinforced composite (FG-CNTRC) micro plate with cut out subjected to magnetic field and resting on elastic medium. The basic formulation of plate is based on first order shear deformation theory (FSDT) and the material properties of FG-CNTRCs are presumed to be changed through the thickness direction, and are assumed based on rule of mixture; moreover, nonlocal Eringen's theory is applied to consider the size-dependent effect. It is considered that the system is embedded in elastic medium and subjected to longitudinal magnetic field. Energy approach, domain decomposition and Rayleigh-Ritz methods in conjunction with Newton-Raphson iterative technique are employed to trace the post-buckling paths of FG-CNTRC micro cut out plate. The influence of some important parameters such as small scale effect, cut out dimension, different types of FG distributions of CNTs, volume fraction of CNTs, aspect ratio of plate, magnitude of magnetic field, elastic medium and biaxial load on the post-buckling behavior of system are calculated. With respect to results, it is concluded that the aspect ratio and length of square cut out have negative effect on post-buckling response of micro composite plate. Furthermore, existence of CNTs in system causes improvement in the post-buckling behavior of plate and different distributions of CNTs in plate have diverse response. Meanwhile, nonlocal parameter and biaxial compression load on the plate has negative effect on post-buckling response. In addition, imposing magnetic field increases the post-buckling load of the microstructure.