• 제목/요약/키워드: structural rules

검색결과 347건 처리시간 0.024초

Effects of plate slenderness on the ultimate strength behaviour of foam supported steel plate elements

  • Pokharel, Narayan;Mahendran, Mahen
    • Structural Engineering and Mechanics
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    • 제21권4호
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    • pp.407-422
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    • 2005
  • Plate elements in fully profiled sandwich panels are generally subjected to local buckling failure modes and this behaviour is treated in design by using the conventional effective width method for plates with a width to thickness (b/t) ratio less than 100. If the plate elements are very slender (b/t > 1000), the panel failure is governed by wrinkling instead of local buckling and the strength is determined by the flexural wrinkling formula. The plate elements in fully profiled sandwich panels do not fail by wrinkling as their b/t ratio is generally in the range of 100 to 600. For this plate slenderness region, it was found that the current effective width formula overestimates the strength of the fully profiled sandwich panels whereas the wrinkling formula underestimates it. Hence a new effective width design equation has been developed for practical plate slenderness values. However, no guidelines exist to identify the plate slenderness (b/t) limits defining the local buckling, wrinkling and the intermediate regions so that appropriate design rules can be used based on plate slenderness ratios. A research study was therefore conducted using experimental and numerical studies to investigate the effect of plate slenderness ratio on the ultimate strength behaviour of foam supported steel plate elements. This paper presents the details of the study and the results.

FE and ANN model of ECS to simulate the pipelines suffer from internal corrosion

  • Altabey, Wael A.
    • Structural Monitoring and Maintenance
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    • 제3권3호
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    • pp.297-314
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    • 2016
  • As the study of internal corrosion of pipeline need a large number of experiments as well as long time, so there is a need for new computational technique to expand the spectrum of the results and to save time. The present work represents a new non-destructive evaluation (NDE) technique for detecting the internal corrosion inside pipeline by evaluating the dielectric properties of steel pipe at room temperature by using electrical capacitance sensor (ECS), then predict the effect of pipeline environment temperature (${\theta}$) on the corrosion rates by designing an efficient artificial neural network (ANN) architecture. ECS consists of number of electrodes mounted on the outer surface of pipeline, the sensor shape, electrode configuration, and the number of electrodes that comprise three key elements of two dimensional capacitance sensors are illustrated. The variation in the dielectric signatures was employed to design electrical capacitance sensor (ECS) with high sensitivity to detect such defects. The rules of 24-electrode sensor parameters such as capacitance, capacitance change, and change rate of capacitance are discussed by ANSYS and MATLAB, which are combined to simulate sensor characteristic. A feed-forward neural network (FFNN) structure are applied, trained and tested to predict the finite element (FE) results of corrosion rates under room temperature, and then used the trained FFNN to predict corrosion rates at different temperature using MATLAB neural network toolbox. The FE results are in excellent agreement with an FFNN results, thus validating the accuracy and reliability of the proposed technique and leads to better understanding of the corrosion mechanism under different pipeline environmental temperature.

국제적(國際的) 건축(建築) 전문교육(專門敎育) 인증기준(認證基準)에서 본 한국(韓國) 건축교육(建築敎育)의 현황분석(現況分析) (A Critical Analysis on the Architectural Education in Korea from the view of International Accrediting Criteria)

  • 류전희;이선영
    • 건축역사연구
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    • 제8권3호
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    • pp.75-89
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    • 1999
  • Under the WTO system, global standardization of professionalism in architecture practice calls for transformation of curriculum in architectural education in Korea. This paper compares the curriculum standards of international accrediting authorities such as NAAB and RIBA based on UIA accord which defines fundamental knowledge and abilities of an architect. As a result this paper extracts 51 achievement oriented criteria of architectural education in Korea. It can be categorized as communication, design, cultural context(history and theory, human behavior and social aspects), technical systems(structural systems, environmental control systems, construction material and assemblies) and practice(project process, project economics and business management, laws and regulations). Based on this recommended Korean curriculum standards, current curriculum is analyzed focusing on the 5 architectural programs in Seoul. Through this analysis, it became clear that some area - social and economic aspects in architecture, sustainability in architecture, understanding and selection of construction material, assemblies and environmental control system, recycling of existing building, professional liability, professional rules of conduct, project economics and project management - need to be covered and emphasized to meet the international standards in professional education in architecture. The result in this paper will be used as a basic data in the process of finding the direction of restructuring curriculum for professional architectural education in Korea.

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연속 동조 방법을 이용한 퍼지 집합 퍼지 모델의 유전자적 최적화 (Genetic Optimization of Fyzzy Set-Fuzzy Model Using Successive Tuning Method)

  • 박건준;오성권;김현기
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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    • pp.207-209
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    • 2007
  • In this paper, we introduce a genetic optimization of fuzzy set-fuzzy model using successive tuning method to carry out the model identification of complex and nonlinear systems. To identity we use genetic alrogithrt1 (GA) sand C-Means clustering. GA is used for determination the number of input, the seleced input variables, the number of membership function, and the conclusion inference type. Information Granules (IG) with the aid of C-Means clustering algorithm help determine the initial paramters of fuzzy model such as the initial apexes of the, membership functions in the premise part and the initial values of polyminial functions in the consequence part of the fuzzy rules. The overall design arises as a hybrid structural and parametric optimization. Genetic algorithms and C-Means clustering are used to generate the structurally as well as parametrically optimized fuzzy model. To identify the structure and estimate parameters of the fuzzy model we introduce the successive tuning method with variant generation-based evolution by means of GA. Numerical example is included to evaluate the performance of the proposed model.

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SOA기반 워크플로우 환경에서 DSML의 구조적 접근방법을 사용한 프라이버시 정책 모델의 통합과 검증 (Integration and Verification of Privacy Policies Using DSML's Structural Semantics in a SOA-Based Workflow Environment)

  • 이용환;얀워너;야노스스테파노비치
    • 인터넷정보학회논문지
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    • 제10권4호
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    • pp.139-149
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    • 2009
  • 본 논문에서는 데이터 보호 규정에 관련된 요구사항들이나 규칙들이 소프트웨어에 잘 표현되어 있는지를 검증하기 위하여 도메인 고유의 언어인 DSML(Domain Specific Modeling Language)을 사용해 정책을 정규화 혹은 계산적 표현에 관련된 솔루션을 제시하고 있다. 모든 정책들은 공식적으로 프롤로그( Prolog) 언어 기반으로 표현된 후 DSML에 통합되며 정책검증은 요구사항 준수가 언제 평가되어야 하는지에 따라 정적 정책검증과 동적 정책검증의 두가지 정책이 존재한다.

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Influence of ductility classes on seismic response of reinforced concrete structures

  • Nikolic, Zeljana;Zivaljica, Nikolina;Smoljanovic, Hrvoje
    • Coupled systems mechanics
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    • 제7권2호
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    • pp.177-195
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    • 2018
  • Reinforced concrete buildings in a seismically active area can be designed as DCM (medium ductility) or DCH (high ductility) class according to the regulations of Eurocode 8. In this paper, two RC buildings, one with a wall structural system and the other with a frame system, previously designed for DCM and DCH ductility, were analysed by using incremental dynamic analysis in order to study differences in the behaviour of structures between these ductility classes, especially the failure mechanism and ultimate collapse acceleration. Despite the fact that a higher behaviour factor of DCH structures influences lower seismic resistance, in comparison to DCM structures, a strict application of the design and detailing rules of Eurocode 8 in analysed examples caused that the seismic resistance of both frames does not significantly differ. The conclusions were derived for two buildings and do not necessarily apply to other RC structures. Further analysis could make a valuable contribution to the analysis of the behaviour of such buildings and decide between two ductility classes in everyday building design.

갑판지지 웨브 구조에서의 개구부 상세설계기준 정립 (Detail-design Guidance for the Openings on the Web Structure Supporting the Deck)

  • 김성찬;이경석;송재영;김경수
    • 대한조선학회논문집
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    • 제44권6호
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    • pp.612-618
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    • 2007
  • There are a lot of openings, holes and slots in ship structural members. It is not easy to solve the troubles around the openings adequately at the detail design stage, because there are a lot of concerning locations. There are not also clear design rules of classification societies and it is not possible to apply direct calculation for all the concerning members. Therefore, it is necessary to set up simplified approach such as a standard or guidance in order to decide the opening design quickly. For this study, guidance and regulations of each classification and several companies were surveyed. Grillage analysis and the refined mesh method were used to evaluate the strength around hole considering boundary condition and more detailed member arrangement. As a result, the standard for opening design was established and verified.

게임 캐릭터의 감정구조를 위한 감정규칙의 활용 (Use of Emotion Rule for Game Characters Emotion Structure)

  • 박준형;고일주;성보경
    • 한국게임학회 논문지
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    • 제16권1호
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    • pp.23-32
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    • 2016
  • 최근 감정에 대한 연구는 게임을 하는 사용자와의 상호작용을 높이는 요소로 주목 받고 있다. 그 동안 게임에서 표현되는 감정은 간단한 구조를 사용했었다. 하지만 게임에서 사용되는 감정에 대한 사용자의 요구가 높아지면서 감정을 구조화시킬 필요가 생겼다. 이 논문에서는 게임 속 캐릭터의 감정을 위해 생물학적 감정 원리를 기반으로 제안된 감정규칙을 활용했다. 그리고 감정에 영향을 주는 게임 구성요소를 분류하고 캐릭터가 게임에서 감정을 인지하기 위한 구조를 제안한다. 이를 통해 기존의 게임에서 사용된 감정을 감정의 역할로 분석하고 게임에서 감정을 표현하기 위해 고려해야할 구조적인 틀을 제안한다.

Performance analysis tool for reinforced concrete members

  • Esmaeily, Asad;Peterman, Robert J.
    • Computers and Concrete
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    • 제4권5호
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    • pp.331-346
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    • 2007
  • A computer program was developed to analyze the non-linear, cyclic flexural performance of reinforced concrete structural members under various types of loading paths including non-sequential variations in axial load. This performance is significantly affected by the loading history. Different monotonic material models as well as hysteresis rules for confined and unconfined concrete and steel, some developed and calibrated against test results on material samples, were implemented in a fiber-based moment-curvature and in turn force-deflection analysis. One of the assumptions on curvature distribution along the member was based on a method developed to address the variation of the plastic hinge length as a result of loading pattern. Functionality of the program was verified by reproduction of analytical results obtained by others for several cases, and accuracy of the analytical process and the implemented models were evaluated against the experimental results from large-scale reinforced concrete columns tested under the analyzed loading cases. While the program can be used to predict the response of a member under a certain loading pattern, it can also be used to examine various analytical models and methods or refine a custom material model against test data.

기하학적 변위 이론을 적용한 VLCC 최종종강도 평가 (Assessment of Ultimate Longitudinal Strength of a VLCC considering Kinematic Displacement Theory)

  • 정준모;남지명;;윤성원;이강수
    • 대한조선학회논문집
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    • 제50권4호
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    • pp.255-261
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    • 2013
  • This paper presents prediction of ultimate longitudinal strength of a VLCC, "Energy Concentration" for which many benchmark studies have been carried out, based on kinematic displacement method proposed by Tayyar and Bayraktarkatal (2012). Kinematic displacement theory provides semi-analytical solution of average compressive strengths for various kinds of stiffened panels. The accuracy of average compressive strengths obtained from formulas of CSR(common structural rules) for tankers and kinematic displacement method are discussed in the fore part of this paper. Hull girder ultimate strengths using Smith method are also compared for different average compressive strengths. By comparing them with other benchmark results, it is concluded that the new method provides lower bounds, because hull girder strengths under the sagging and hogging moment conditions approach nearly lower bounds.