• Title/Summary/Keyword: analysis

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Wave Transmission Analysis of Semi-infinite Mindlin Plates Coupled at an Arbitrary Angle (임의의 각으로 연성된 반무한 Mindlin 판의 파동전달해석)

  • Park, Young-Ho
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.24 no.12
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    • pp.999-1006
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    • 2014
  • Mindlin plate theory includes the shear deformation and rotatory inertia effects which cannot be negligible as exciting frequency increases. The statistical methods such as energy flow analysis(EFA) and statistical energy analysis(SEA) are very useful for estimation of structure-borne sound of various built-up structures. For the reliable vibrational analysis of built-up structures at high frequencies, the energy transfer relationship between out-of-plane waves and in-plane waves exist in Mindlin plates coupled at arbitrary angles must be derived. In this paper, the new wave transmission analysis is successfully performed for various energy analyses of Mindlin plates coupled at arbitrary angles.

A Study on Vibration Analysis Method Using the Global Structural Analysis Model (전선 구조해석 모델을 이용한 진동해석 방법에 관한 연구)

  • Park, Hyung-Sik;Choi, Su-Hyun;Lee, Yong-Sub
    • Journal of the Society of Naval Architects of Korea
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    • v.44 no.3 s.153
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    • pp.314-322
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    • 2007
  • In general, the vibration and structural analyses have been carried out by using each finite element model separately because of different size of finite element mesh and different focusing area of each analysis. In some cases, however, it is required to perform both global vibration and structural analyses at the same time using a finite element model for global structural analysis, which asks for a special treatment for a vibration analysis. In this study, a technique to perform a global vibration analysis using a finite element model for a global structural analysis has been developed and its effectiveness has been verified by its application to a whole ship.

Automated FEA Simulation of Micro Motor (마이크로 모터의 자동화된 FEA 시뮬레이션)

  • Lee Joon-Seong
    • Journal of the Korea Society for Simulation
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    • v.11 no.3
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    • pp.13-22
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    • 2002
  • This paper describes an automated evaluation of electrostatic field for micro motors whose sizes range 10 to 103um. Electric field modeling in micro motors has been generally restricted to in-plane two-dimensional finite element analysis (FEA). In this paper, the actual three-dimensional geometry of the micro motor is considered. An automatic FE mesh generation technique, which is based on the fuzzy knowledge processing and computational geometry techniques, is incorporated in the system, together with one of commercial FE analysis codes and one of commercial solid modelers. The system allows a geometry model of concern to be automatically converted to different FE models, depending on physical phenomena to be analyzed, electrostatic analysis and stress analysis and so on. The FE models are then exported to the FE analysis code, and then analyses are peformed. Then, analytical analysis and FE analysis about the torque generated by electrostatic micro motor are performed. The starting torque is proportional to $V^2$, the calculated starting torque from the two-dimensional analytical solutions are three times larger than those from the three-dimensional FE solutions.

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Forming Analysis of the Front Side Member using Equivalent Draw-bead for Crashworthness Assessment (등가 드로오비드를 적용한 Front Side Member의 성형해석 및 충돌평가)

  • Song, J.H.;Kim, K.P.;Kim, S.H.;Huh, H.;Kim, H.S.;Hong, S.G.
    • Transactions of Materials Processing
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    • v.12 no.4
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    • pp.320-327
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    • 2003
  • This paper is concerned with forming analysis of Front Side Members and effects of the forming analysis on crash analysis of an auto-body. For efficient forming analysis, equivalent draw-bead restraining forces are calculated with ABAQUS/Standard and then used as the boundary condition in forming simulation. In order to demonstrate the validity of the forming analysis, the thickness variation in the numerical simulation result is compared quantitatively with the one in the real product. Forming histories obtained kom the forming analysis are utilized as the initial condition of the crash analysis for accurate assessment of the crashworthiness. Crashworthiness such as the load-carrying capacity, crash mode and the energy absorption is evaluated and investigated for the identification of forming effects.

Application of Risk Analysis for Economic Evaluation of Railroad Investments (위험도 분석을 이용한 철도투자사업 경제성평가 적용방안)

  • Lee, Ho;Suh, Sun-Duck
    • Proceedings of the KSR Conference
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    • 2001.05a
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    • pp.44-51
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    • 2001
  • To account for uncertainties involved in an economic analysis of project, sensitivity analysis are usually being done in Korea. Though useful for policy analysis, but it larks explicit consideration of probability of occurring certain events considered in the sensitivity analysis. Risk analysis otherwise can explicitly account for the probability of certain event which has dire impact on project viability, such as cost, discount rate, and size of benefit. This paper reports experience of applying risk analysis method for economic evaluation of railroad investment. Probability distribution of event has paramount impact on the risk analysis results, while not many prior researches dealt with these issues. Probability distribution of rolling stock cost and operating cost, in addition to those cost variables, are developed considering railway demand in this study. Case study results are reported. Issues in applying risk analysis are reported in addition to further research direction.

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Conversation Analysis for Improving Nursing Communication (간호 커뮤니케이션 향상을 위한 대화 분석적 접근)

  • Yi, Myung-Sun
    • Journal of Korean Academy of Nursing
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    • v.37 no.5
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    • pp.772-780
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    • 2007
  • Purpose: Nursing communication has become more important than ever before because quality of nursing services largely depends on the quality of communication in a very competitive health care environment. This article was to introduce ways to improve nursing communication using conversation analysis. Methods: This was a review study on conversation analysis, critically examining previous studies in nursing communication and interpersonal relationships. Results: This study provided theoretical backgrounds and basic assumptions of conversation analysis which was influenced by ethnomethodology, phenomenology, and sociolinguistic. In addition, the characteristics and analysis methods of conversation analysis were illustrated in detail. Lastly, how conversation analysis could help improve communication was shown, by examining researches using conversation analysis not only for ordinary conversations but also for extraordinary or difficult conversations such as conversations between patients with dementia and their professional nurses. Conclusion: Conversation analysis can help in improving nursing communication by providing various structures and patterns as well as prototypes of conversation, and by suggesting specific problems and problem-solving strategies in communication.

Ultimate Strength Analysis of Ring-stiffened Cylinders Using Commercial softwares (I) (상용소프트웨어를 이용한 원환보강 원통의 최종강도 해석(I))

  • 박치모;이승훈
    • Journal of Ocean Engineering and Technology
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    • v.15 no.2
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    • pp.120-123
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    • 2001
  • Despite the increasing necessity of accurate estimation of ring-stiffened cylinders'ultimate strength, the complex structural behavior of cylinders has made their design mainly depend on empirical formulas mostly based on limited test data rather than theoretical background. This paper has developed the imperfection method which enables the ultimate strength analysis of buckling-sensitive structures by combining two separate functions covered by common commercial finite element softwares, which are linear elastic buckling analysis and nonlinear stress analysis. Developed method was applied to two of the world most renowned softwares, MSC/NASTRAN and ABAQUS, for the analysis of ring-stiffened cylinders and unexpectedly big difference in their analysis results was found. This tells that many widely used commercial softwares have their different strong points and weak points and the choice of commercial software should be cautiously made after thorough inspection. This paper ends with some useful information about which of the two aforementioned softwares is more respectively for the linear elastic buckling analysis and the ultimate strength analysis of ring-stiffened cylinders.

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Design Rainfall for Slope Stability Analysis and Its Application (사면안정해석을 위한 설계강우 산정과 적용방안)

  • Kim, Kyung-Suk;Jang, Hyun-Ick;Chung, Choong-Ki
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.10a
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    • pp.957-965
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    • 2008
  • Recently, slope stability analysis in current design criteria is criticized for its unrealistic assumption of groundwater table and slope stability analysis incorporating seepage analysis considering rainfall is gaining a recognition as an alternative. However, a reasonable method for determining the rainfall used in the seepage analysis has not yet been established. Rainfall input for seepage analysis is a time series of rainfall and is similar to the hyetograph which is usually obtained from hydrology. In this paper a method to obtain the hyetograph from the intensity-duration-frequency is proposed. The resulting hyetograph can be used in the in the slope design stage. Also some considerations for practical application of slope stability analysis considering the rainfall is included.

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Study on the Numerical Analysis of Model Ground with SCP (SCP가 타설된 모형지반의 압밀거동에 관한 수치해석적 연구)

  • Hwang, Sung-Pil;Im, Jong-Chul;Kang, Yeoun-Ike;Kwon, Jeong-Geun;Joo, In-Gon
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.09a
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    • pp.1224-1231
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    • 2009
  • 1D Analysis have been using Design of SCP in order to improve the soft ground. But 2D Analysis is researching and developing to get more accurate results. Using 2D Analysis, suitable Numerical Analysis Model should be selected and be tested in many situations. In this study, Laboratory Model Tests are analyzed by Numerical Analysis Method. After selecting Numerical Analysis Model, it is being tested many conditions.

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Analysis for Soil Pollution by Heavy Metals in the Area of Kyongbuk (경북지역 토양의 중금속 분석)

  • Dho, Hyon-Seung;Kim, Sung-Duk;Lee, Seung-Joo
    • Journal of the Korea Safety Management & Science
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    • v.12 no.2
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    • pp.231-236
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    • 2010
  • The investigation was initiated with data from 27 abandoned mines along with 12 locations in Kyongbuk abandoned mines. The analyses for soil pollution by heavy metal pollutants were conducted by using correlation analysis, cluster analysis, and principal component analysis. The correlation analysis indicated that Ni and pH were highly correlated compared to those of other heavy metal ions. The principal component analyses showed that the heavy metal ions might be classified into two catagories, such as antropogenic and lithogenic components. The cluster analysis was also clearly divided by two groups. The respective two groups might be Pb-Zn-Cd-Cu and As-Hg-Ni.