• 대한의용생체공학회:의공학회지
• /
• 제21권6호
• /
• pp.559-566
• /
• 2000

Methodology for finite element analysis of vertebral column and pedicle screw system, which circumvents the tremendous difficulties in geometric, material, and structural modeling, is proposed. The simplification is focused on the modeling of the cancellous bone in vertebral body the intervertebral disc. and the instrumented internal fixation devices. Each proposed modeling technique is justified to result in reasonable accuracy. These methods are believed to be suitable for the development of pedicle screw systems, not only because modeling itself is much simpler. but also because reliable empirical data for disc stiffness may be incorporated with little additional effort, and presumably frequent design change may be easily reflected on the analysis.

• 한국생산제조학회지
• /
• 제19권4호
• /
• pp.511-520
• /
• 2010

In general, spot welding is used at no welding rod or flux for the process, low welding point temperature compared to arc welding, short heating time, less damage to the parent material, and low deformation and residual stress, relatively. Also, because of the pressurization effect, better mechanical qualities of the welding parts are obtained. Therefore, in various fields of industry its rapid operation speed can make mass production possible such as motor industry. In FEM analysis for the spot welding process, it is effective to use simple modeling rather than complicated one because of its numerous number of spots and reduction of analysis time. Therefore, this study provides with not only simplification of modeling analysis by using beam component composition of structure without re-compositing the spot welding point mesh but also modeling analysis of which property of fracture strength is reflected. In addition complete spot welding model is examined at rectangular post shape (hat shape) by impact test, compared the results, and verified its validity. As a result, it is possible to optimize the welding position and to recognize the strength of structure and the proposed equal distance model shows the effect of welding point reduction and improvement of stiffness.

• 한국항공우주학회지
• /
• 제39권12호
• /
• pp.1160-1165
• /
• 2011

본 연구는 무인항공기 및 헬리콥터 등에 장착되어 운용되는 고정밀 관측 다축 구동 EO/IR 카메라의 진동해석에 관한 것이며, 카메라에 적용된 볼 베어링을 모델링 하는데 있어서 3축 스프링요소를 적용하는 방법을 제시하였고, 이것에 의한 유한요소모델의 진동 응답 결과를 얻었다. 볼 베어링을 3축 스프링 요소로 모델링한 진동해석결과는 시험결과와 비교 되었으며, 잘 일치함을 알 수 있었다. 또한, 랜덤진동 시간이력해석을 통하여 다축 구동 EO/IR 카메라의 진동 응답 특성을 해석하고 분석하였다. 이의 연구결과는 우주용 카메라들에 사용되는 볼 베어링의 유한요소모델링 기법에 응용될 수 있다.

• 디지털융복합연구
• /
• 제14권9호
• /
• pp.111-121
• /
• 2016

본 연구는 R을 이용하여 구조방정식모형에서 이중매개효과 분석을 수행하는 방안을 제시하고 있다. 이를 위해 본 연구에서는 매개효과 분석을 위한 다양한 기법들에 대한 문헌연구를 통해 부트스트랩 기법을 이중매개 효과분석을 수행하는데 있어서 가장 적합한 기법으로 선정하고, PLS 경로분석 수행을 지원하는 R패키지인 plspm을 이용하여 구조방정식모델링에서 부트스트랩 기반의 이중매개효과를 분석하는 방안을 개발했다. 결과물로 본 연구에서는 예시모형을 대상으로 한 이중매개효과 분석기법과 관련 R스크립트들이 제시되었다. 본 연구는 대부분의 SEM 패키지들에서 지원하지 못하는 구조방정식모델링에서의 이중매개효과 분석을 포함하는 연구들에서 유용하게 활용될 것이며, 또한 연구자들에게 R을 이용한 새로운 매개효과 분석기법 제시를 통하여 심도 있는 연구를 위한 기반 지식을 제공할 것이다.

• 한국지능시스템학회논문지
• /
• 제19권5호
• /
• pp.720-724
• /
• 2009

본 논문에서는 FSM을 이용하여 기업프로젝트의 성공요인에 대한 의식구조를 분석한다. FSM은 ISM에 퍼지이론을 도입한 것으로서 다원적 가치가 복합되어 있는 시스템의 구조 인식에 보다 유효하다고 알려져 있으며, parameter p와 $\lambda$에 의해 변화되는 구조모형을 현실에 맞는 것으로 선택하도록 되어있다. 이것은 구조모형으로서의 객관적인 적합성평가를 실시하지 않은 상태에서 선택하는 것이기 때문에 선택된 구조모형이 현실에 적합하다고 판단된다 하더라도 보완적인 차원에서 구조 모형의 적합성평가를 실시하는 것이 바람직하다고 할 수 있다. 따라서 본 논문에서는 FSM을 이용하여 구한 기업프로젝트 달성을 위한 성공요인에 대한 구조모형에 대하여 구조방정식 모형분석을 이용한 적합성을 평가하여 보다 객관성 있는 구조모형을 제시하고 그 구조모형에 따라 의식구조를 분석한다.

• 한국전산구조공학회:학술대회논문집
• /
• 한국전산구조공학회 2002년도 가을 학술발표회 논문집
• /
• pp.131-138
• /
• 2002

The fuel handling machine handles the core assembly in refueling period of the reactor, it is necessary to predict the motion and structural integrity of it. The kinetic analysis of the fuel handling machine was carried out for the refueling motion. The reaction forces at the joints of machine were calculated with IDEAS code considering the weight of the machine and the loading force of the core assembly, Also, the structural analysis for the machine modeled by lumped-mass and beam elements was performed by using ANSYS code. The stresses and deformations were calculated for the equivalent static force based on the kinetic analysis and the seismic loads. The calculated displacements and stresses are quite low compared with allowable limits.

• 한국소음진동공학회논문집
• /
• 제22권1호
• /
• pp.81-87
• /
• 2012

This paper establishes a modeling and simulation procedure for structural response and reliability of a cylindrical array sensor on submarines under the shock generated by underwater explosion. The structural reliability of SONAR is important because the submarine could get out of combat ability by the structural damage of the SONAR upon explosion. A cylindrical array sensor was first modeled using the finite element method. Modal analysis was then performed for the check of the reliability of the modeling. The shock resistance simulations were performed for the responses to the structural shock waves and for the responses to the directly applied underwater shock waves, according to BV-043 and MIL-STD-901D, respectively. The stresses of the structure were evaluated with von-Mises scheme. Vulnerable regions were exposed through mapping the maximum stress to the structural model. Maximum stress of the SONAR was compared with the yield stress of the material to examine the structural reliability.

• International Journal of Quality Innovation
• /
• 제9권3호
• /
• pp.145-162
• /
• 2008

Since the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China published the GB/T19580-2004: Criteria for Excellence Performance of China, many enterprises in China have adopted the Criteria to enhance their organization business management and to assess or self-assess organization performance. On the bases of both the Criteria for Excellence Performance of China and the survey data from China Association for Quality (CAQ), this paper systematically explores the relationships among 'leadership', 'strategy planning', 'customer and market', 'information, analysis and improvement', 'resources management', 'process management', and 'performance results' by using structural equations modeling and validates some of the anecdotal beliefs in quality management. This quantitative analysis provides a guideline for organizations in China to identify causal linkage among core value of total quality management and to identify strengths, deficiency, and opportunities to enhance competitive advantages and ensure the future business success.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제13권3호
• /
• pp.1184-1198
• /
• 2019

This study aims to use ISM to identify the enablers affecting the acceptance of IoT services. For this purpose, this study conducted an ISM analysis and a MICMAC analysis, extracted the enablers from Internet of Things - An Action Plan for Europe published by the EU for the research, and conducted interviews and surveys. The study found that it would be preferentially necessary to prepare the base for successful IoT services through international cooperation and the security of objective data. In addition, it turned out that it would be necessary to make efforts to spread and develop IoT services by conducting R&D and implementing projects through public-private partnerships and the organization of a consultative group. Lastly, since information security and standardization are the desired objects of the IoT industry, it was found that both the government and the industrial world should focus on them. This study has significance in that it can provide practical implications for the effective acceptance of IoT services.

• 대한조선학회논문집
• /
• 제40권6호
• /
• pp.30-36
• /
• 2003

To improve survivability of damaged ship, assessment of stability and structural safety, and behavior analysis in wave is required. Prediction of sinking time, damage stability and structural strength considering progressive flooding and dynamic force in wave is very important. To do it, a geometric model which can be express damaged ship is prepared. This paper described the geometric modeler for survivability assessment of damaged ship. The modeler is developed based on 3-D geometric modeling kernel, ACIS. The hull form and compartment definition is available fundamentally. And requirement for modeler contains data generation and interface for hydrostatic calculation, behavior analysis, and longitudinal strength analysis and so on. To easy access modeling system by conventional user such as crew, user interface is developing.