• Title/Summary/Keyword: structural methodology

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Application of Knowledge-Based System in the Design of Pre-cast Concrete Member (프리캐스트 콘크리트 부재설계에서 지식기반시스템의 적용)

  • 김성중;이승창;이병해
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1995.04a
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    • pp.176-183
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    • 1995
  • The design process of pre-cast concrete member needs various design parameters and the engineer's experiences. The introduction of knowledge-based system in the design of pre-cast concrete member enables us to design complicated members using the designer's heuristics. The objectives of this research are to study useful methodology for representing knowledge and data in the development of knowledge-based system and to show the application of methodology by developing a prototype sysytem for design of pre-cast concrete member. This paper nrst describes methodology for building knowledge-based system. It then presents knowledge-based system for pre-cast concerete member design.

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Thermo-elastic Creep and Frequency Optimization by Using Feasible Direction Method (Feasible Direction Method를 사용한 열.탄성.크리프 및 진동수에 대한 최적화)

  • Jo, Hui-Geun;Park, Yeong-Won;Gang, Yeon-Sik;Lee, Gyeong-Don
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.25 no.5
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    • pp.857-865
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    • 2001
  • In finite element analysis, engineering optimizations are divided two major parts that are topology and structural optimization. Until these days most structural optimizations usually concentrate on single disciplinary optimization. Therefore numerical analysis and methodology which can optimize thermo-elastic creep and frequency phenomena are not suggested. In this paper finite element analysis methodology and algorithm of thermo -elastic creep and frequency optimizations are suggested and corroborate the efficiency of suggested new numerical methodology and algorithm by solving example problem.

Application of Formal Safety Assessment Methodology to Marine Structural Design (공식안전평가기법의 선박해양구조설계에의 적용)

  • Lee, Joo-Sung
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2001.05a
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    • pp.133-138
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    • 2001
  • Formal safety assessment (FSA) is defined as a structured and systematic methodology aimed at enhancing maritime safety including protection of life, health, and the marine environment and property, by using risk and cost/benefit assessment or, more specifically, it is a process of identifying hazard, evaluating risk and deciding on course of action to control those risks. Emphasis is placed on the structural aspect of the failure of cargo hold. This study is expected to illustrate how a new methodology, i.e. the Formal Safety Assessment, can be applied to specific ship safety problems.

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Damage Prediction Accuracy as a Function of Model Uncertainty in Structures (모델의 불확실성이 구조물의 손상예측정확도에 미치는 영향)

  • 김정태
    • Computational Structural Engineering
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    • v.7 no.3
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    • pp.153-166
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    • 1994
  • A methodology to assess damage prediction accuracy as a function of model uncertainty in structures is presented. In the first part, a theory of approach is outlined. First, a damage detection algorithm to locate and size damage in structures using few modal responses of the structures is summarized. Next, methods to quantify model uncertainty and the damage detection accuracy are formulated. In the second part, a methodology to assess the effect of model uncertainty on the damage detection accuracy of real structures is designed. In the last part, the feasibility of the assessment methodology is demonstrated by using a plate-girder bridge for which only information on a single mode is available.

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Preliminary design and inelastic assessment of earthquake-resistant structural systems

  • Rubinstein, Marcelo;Moller, Oscar;Giuliano, Alejandro
    • Structural Engineering and Mechanics
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    • v.26 no.3
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    • pp.297-313
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    • 2007
  • A preliminary performance-based seismic design methodology is proposed. The top yield displacement of the system is computed from these of the components, which are assumed constant. Besides, a simple procedure to evaluate the top yield displacement of frames is developed. Seismic demands are represented in the form of yield point spectra. The methodology is general, conceptually transparent, uses simple calculations based on first principles and is applicable to asymmetric systems. To consider a specific situation two earthquake levels, occasional and rare are considered. The advantage of an arbitrary assignment of strength to the different components to reduce eccentricities and improved the torsional response of the system is addressed. The methodology is applied to an asymmetric five story building, and the results are verified by push-over analysis and non linear dynamic analysis.

LOADOUT DEVELOPMENT BY F.E. ANALYSIS METHODOLOGY FOR SIMILAR 300K VLCC SIZE FSO

  • Yang, Y.T.;Kang, H.S.
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2002.10a
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    • pp.51-55
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    • 2002
  • End of July. 2002 Hyundai Heavy Industries Co. Ltd. Offshore Division is successfully completed Load-out & Float-off work of "AMENAM KPONO/FSO Project" similar to 300K VLCC size. The AMENAM FSO hull and topside module built at the HHI Offshore yard using "On-Ground Building Method" developed by HHI. Various methodologies/techniques like Flexi-built FPSO Hull. Topside module erection method. Load-out Float-off methodology etc. are combined to develop a successful on-ground building method. In this paper, we described the "Hull Structural Strength Analysis Methodology" using 3-D Finite Element Analysis and results. This analysis is performed to verily the structural integrity or the AMENAM FSO hull during the main load-out on two semi-submersible barges combined together.

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Finite element analysis based fatigue life evaluation approach for railway bridges: a study in Indian scenario

  • Ajmal, P.C. Hisham;Mohammed, Althaf
    • Structural Monitoring and Maintenance
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    • v.5 no.4
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    • pp.429-443
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    • 2018
  • Fatigue is a principal failure mode for steel structures, and it is still less understood than any other modes of failure. Fatigue life estimation of metal bridges is a major issue for making cost effective decisions on the rehabilitation or replacement of existing infrastructure. The fatigue design procedures given by the standard codes are either empirical or based on nominal stress approach. Since the fatigue life estimation through field measurements is difficult and costly, more researches are needed to develop promising techniques in the fatigue analysis of bridges through Finite Element Analysis (FEA). This paper aims to develop a methodology for the Fatigue life estimation of railway steel bridge using FEA. The guidelines of IIW-1823-07 were used in the development of the methodology. The Finite Element (FE) package ANSYS and the programming software MATLAB were used to implement this methodology on an Indian Railway Standard (IRS) welded plate girder bridge. The results obtained were compared with results from published literature and found satisfactory.

Application of first-order reliability method in seismic loss assessment of structures with Endurance Time analysis

  • Basim, Mohammad Ch.;Estekanchi, Homayoon E.;Mahsuli, Mojtaba
    • Earthquakes and Structures
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    • v.14 no.5
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    • pp.437-447
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    • 2018
  • Computational cost is one of the major obstacles for detailed risk analysis of structures. This paper puts forward a methodology for efficient probabilistic seismic loss assessment of structures using the Endurance Time (ET) analysis and the first-order reliability method (FORM). The ET analysis efficiently yields the structural responses for a continuous range of intensities through a single response-history analysis. Taking advantage of this property of ET, FORM is employed to estimate the annual rate of exceedance for the loss components. The proposed approach is an amalgamation of two analysis approaches, ET and FORM, that significantly lower the computational costs. This makes it possible to evaluate the seismic risk of complex systems. The probability distribution of losses due to the structural and non-structural damage as well as injuries and fatalities of a prototype structure are estimated using the proposed methodology. This methodology is an alternative to the prevalent risk analysis framework of the total probability theorem. Hence, the risk estimates of the proposed approach are compared with those from the total probability theorem as a benchmark. The results indicate a satisfactory agreement between the two methods while a significantly lower computational demand for the proposed approach.

A Study on Factor Analytical Methods and Procedures for PLS-SEM (Partial Least Squares Structural Equation Modeling)

  • YIM, Myung-Seong
    • The Journal of Industrial Distribution & Business
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    • v.10 no.5
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    • pp.7-20
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    • 2019
  • Purpose - This study provides appropriate procedures for EFA to help researchers conduct empirical studies by using PLS-SEM. Research design, data, and methodology - This study addresses the absolute and relative sample size criteria, sampling adequacy, factor extraction models, factor rotation methods, the criterion for the number of factors to retain, interpretation of results, and reporting information. Results - The factor analysis procedure for PLS-SEM consists of the following five stages. First, it is important to look at whether both the Bartlett test of sphericity and the KMO MSA meet the qualitative criteria. Second, PAF is a better choice of methodology. Third, an oblique technique is a suitable method for PLS-SEM. Fourth, a combined approach is strongly recommended to factor retention. PA should be used at the onset. Next, it is recommended using the K1 criterion. In addition, it is necessary to extract factors that increase the total variance explanatory power through the PVA-FS. Finally, it is appropriate to select an item with a factor loading into 0.5 or higher and a communality of 0.5. Conclusions - It is expected that the accurate factor analysis processed for PLS-SEM as previously presented will help us extract more precise factors of the structural model.

Research of Patent Technology Trends in Textile Materials: Text Mining Methodology Using DETM & STM (섬유소재 분야 특허 기술 동향 분석: DETM & STM 텍스트마이닝 방법론 활용)

  • Lee, Hyun Sang;Jo, Bo Geun;Oh, Se Hwan;Ha, Sung Ho
    • The Journal of Information Systems
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    • v.30 no.3
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    • pp.201-216
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    • 2021
  • Purpose The purpose of this study is to analyze the trend of patent technology in textile materials using text mining methodology based on Dynamic Embedded Topic Model and Structural Topic Model. It is expected that this study will have positive impact on revitalizing and developing textile materials industry as finding out technology trends. Design/methodology/approach The data used in this study is 866 domestic patent text data in textile material from 1974 to 2020. In order to analyze technology trends from various aspect, Dynamic Embedded Topic Model and Structural Topic Model mechanism were used. The word embedding technique used in DETM is the GloVe technique. For Stable learning of topic modeling, amortized variational inference was performed based on the Recurrent Neural Network. Findings As a result of this analysis, it was found that 'manufacture' topics had the largest share among the six topics. Keyword trend analysis found the fact that natural and nanotechnology have recently been attracting attention. The metadata analysis results showed that manufacture technologies could have a high probability of patent registration in entire time series, but the analysis results in recent years showed that the trend of elasticity and safety technology is increasing.