• 대한조선학회논문집
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• 제47권4호
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• pp.598-605
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• 2010

The structural design of oil tankers and bulk carriers should be performed based on the Common Structural Rules(CSR) which were recently established by the International Association Classification Societies(IACS). At first, in the structural design viewpoint, the scantling and hullweight based on the CSR should be compared with those of existing rules, and then a minimum weight/cost design should be performed by considering the variation of the number of web and the material property. In this study, the optimum web space and material property will be proposed by performing a minimum weight/cost design of a large oil tanker, and the results will be compared with those of existing ship. The longitudinal members are determined by SeaTrust-Holdan developed by the Korean Register of Shipping(KR), and the transverse members are determined by NASTRAN and PULS.

• Earthquakes and Structures
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• 제10권1호
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• pp.211-238
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• 2016

The Maximum seismic responses of steel buildings with perimeter moment resisting frames (MRF), modeled as complex MDOF systems, are estimated for several incidence angles of the horizontal components and the critical one is identified. The accuracy of the existing rules to combine the effects of the individual components is also studied. Two and three components are considered. The critical response does not occur for principal components and the corresponding incidence angle varies from one earthquake to another. The critical response can be estimated as 1.40 and 1.10 times that of the principal components, for axial load and interstory shears, respectively. The rules underestimate the axial load but reasonably overestimate the shears. The rules are not always inaccurate in the estimation of the combined response for correlated components. On the other hand, totally uncorrelated (principal) components are not always related to an accurate estimation. The correlation of the individual effects (${\rho}$) may be significant, even for principal components. The rules are not always associated to an inaccurate estimation for large values of ${\rho}$, and small values of ${\rho}$ are not always related to an accurate estimation. Only for perfectly uncorrelated harmonic excitations and elastic analysis of SDOF systems, the individual effects of the components are uncorrelated and the rules accurately estimate the combined response. The degree of correlation of the components, the type of structural system, the response parameter under consideration, the location of the structural member and the level of structural deformation must be considered while estimating the level of underestimation or overestimation.

• 대한조선학회 특별논문집
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• 대한조선학회 2011년도 특별논문집
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• pp.17-20
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• 2011

The International Association of Classification Societies (IACS) had developed the Common Structural Rules (CSR) for bulk carriers as per the needs noted above. ISO and IMO GBS (Goal-Based Standards) are now being developed in this regard. This study has been prepared to verity the strength of forward cargo hold of 82,000 DWT class bulk carriers. A cargo hold/tank 3-D FE model was established to assess the structural adequacy of the primary structural members with the loading conditions. Full breadth model was established for the analysis considering asymmetric nature of structural layout and loading conditions. To summarize this result of structural assessment based on IACS CRS for bulk carrier, it is benefit to design this kind of bulk carriers and to study the strength assessment for the similar type of bulk carriers.

• 대한토목학회논문집
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• 제38권2호
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• pp.295-302
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• 2018

국내 회전교차로의 역사가 짧기 때문에 회전교차로에 대한 운전자들의 인지도(통행 규칙, 정의, 위치 등)가 낮을 가능성이 존재하며, 이는 통행규칙 준수에 영향을 미칠 가능성이 있다. 이러한 가정을 기반으로 본 연구는 구조방정식모형을 적용하여 회전교차로에 대한 인지도와 회전교차로 통행 규칙 준수 간의 관계를 분석하고자 하였다. 연구를 위해 경기도 고양시에 거주하는 운전자 526명을 대상으로 온라인 설문조사를 시행하였으며, 설문항목은 회전교차로 인지도, 운전 경력, 회전교차로 통행 규칙 준수 여부에 대한 내용이 포함되었다. 설문조사 내용은 구조방정식모형을 적용하여 분석하였으며, 분석 결과 회전교차로에 대한 인지도가 높을수록, 운전 경력이 높을수록 통행 규칙을 잘 준수하는 것으로 나타났다. 연구 결과를 기반으로 회전교차로 도입으로 인해 발생할 수 있는 초기 부정적인 영향을 감소시키기 위한 이용자 교육 및 홍보방안을 제시하였다.

• Journal of Mechanical Science and Technology
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• 제20권12호
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• pp.2061-2078
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• 2006

The main purpose of this paper is to establish the high temperature structural integrity evaluating procedures for the next generation reactors, which are to be operated at over 500$^{\circ}C$ and for 60 years. To do this, comparison studies of the high temperature structural design codes and assessment procedures such as the ASME-NH (USA), RCC-MR (France), DDS (Japan), and R5 (UK) are carried out in view of the accumulated inelastic strain and the creep-fatigue damage evaluations. Also the application procedures of the ASME-NH rules with the actual thermal and structural analysis results are described in detail. To overcome the complexity and the engineering costs arising from a real application of the ASME-NH rules by hand, all the procedures established in this study such as the time-dependent primary stress limits, total accumulated creep ratcheting strain limits, and the creep-fatigue damage limits are computerized and implemented into the SIE ASME-NH program. Using this program, the selected high temperature structures subjected to two cycle types are evaluated and the parametric studies for the effects of the time step size, primary load, number of cycles, normal temperature for the creep damage evaluations and the effects of the load history on the creep ratcheting strain calculations are investigated.

• 대한조선학회 특별논문집
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• 대한조선학회 2011년도 특별논문집
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• pp.117-126
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• 2011

The buckling assessment of plate panels described in common structural rules (CSR) is to be determined according to the buckling utilization factor with hull girder stresses calculated on net hull girder sectional properties. As the thickness requirement for the buckling assessment of plate panels is not explicitly given in CSR, a lot of time is spent to find the proper thickness of plate panels until reaching to an allowable buckling utilization factor. In this study, in order to reduce time and cost, the thickness requirement of plate panels satisfying buckling assessment was derived. The structural design system included with the thickness requirement for buckling assessment was developed. The system is called as Oil-tanker Automated Structural Investigation System (OASIS). The design result of longitudinal strength members using OASIS was verified by Nauticus Hull which is the rule scantling software of DNV. Finally, optimum design of a double hull tanker for the minimum weight using OASIS was presented.

• 정보화연구
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• 제10권1호
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• pp.71-77
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• 2013

XML 스키마 매칭은 두 스키마의 엘리먼트들 간의 의미적인 유사성을 찾는 작업이다. XML 스키마 매칭은 스키마 통합, 데이터 통합, 데이터 웨어하우징, 데이터 변환, P2P 데이터 관리, 시멘틱 웹 등과 같은 응용체계에서 중요한 역할을 한다. 본 논문은 룰과 구조적 속성에 기반한 XML 엘리먼트 매칭 알고리즘을 제안한다. 제안한 알고리즘에서는 먼저 XML 문서의 구조적 속성을 이용하여 엘리먼트들이 unique와 non-unique로 분류되며, 이후 룰에 따라 엘리먼트의 매칭여부를 결정한다. 제안 알고리즘의 효과성을 보이기 위해 인터넷에 공개된 XML 스키마를 이용하여 성능을 평가하였다. 또한 제안 알고리즘은 문서의 구조적 속성을 이용함으로써 사용자 주관성을 배제하고 객관성을 보장하며 특정 유형이 아닌 다양한 형태의 XML에 적용이 가능하다.

• 대한기계학회논문집
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• 제18권3호
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• pp.777-784
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• 1994

A design expert system for the ship structural design is developed to support inexperienced designers. To establish the knowledge-base, an expert system development shell, Nexpert, is used. Knowledge is extracted from the rules of a classification society of ships, and also from an existing ship structural program that is being used by ship designers. This knowledge is systematized using the objectoriented concept. The design support system is constructed by adding additional functions which are required for the conventional engineering design work. Added functions are; calculation of longitudinal strength, database of existing ship designs, graphical user interface, and visualization of design results. It is observed that visualizing the relationships among the rules, which are activated to draw a certain design decision, is helpful. The system can easily be updated according to changes of the rule books of ship classification societies.

• Wind and Structures
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• 제12권5호
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• pp.425-439
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• 2009

The expediency of revising universal rules for the combination of gravity and lateral actions of wind force-resisting steel structures recommended by the Standards EN 1990 and ASCE/SEI 7-05 is discussed. Extreme wind forces, gravity actions and their combinations for the limit state design of structures are considered. The effect of statistical uncertainties of extreme wind pressure and steel yield strength on the structural safety of beam-column joints of wind force-resisting multistory steel frames designed by the partial factor design (PFD) and the load and resistance factor design (LRFD) methods is demonstrated. The limit state criterion and the performance process of steel frame joints are presented and considered. Their long-term survival probability analysis is based on the unsophisticated method of transformed conditional probabilities. A numerical example illustrates some discrepancies in international design standards and the necessity to revise the rule of universal combinations of loads in wind and structural engineering.

• Journal of Ship and Ocean Technology
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• 제12권1호
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• pp.45-56
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• 2008

Recently, International Association Classification Societies (IACS) has adopted the Common Structural Rules (CSR) for Bulk Carriers and Tankers, which specifies the requirement associated with the ultimate strength of hull girder structure. The theoretical background and the results of verification study are neither well summarized nor released. Furthermore, the requirement is not a form of deterministic formula but a form of program in which source code is not disclosed. The reliability of the non-linear structural analysis program is verified through the comparison with the results of the analysis and the model test. Then, the reliability of the ultimate strength requirement in CSR is checked by comparing with the results of rigorous non-linear analysis.