• Structural Engineering and Mechanics
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• 제39권2호
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• pp.287-301
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• 2011

This paper is focused on the residual capacity of steel columns, as a damage criterion. Load-Impulse (P-I) diagrams are frequently used for analysis, design, or assessment of blast resistant structures. The residual load carrying capacity of a simply supported steel column was derived as a damage criterion based on a SDOF computational approach. Dimensionless P-I diagrams were generated numerically with this quantitative damage criterion. These numerical P-I diagrams were used to show that traditional constant ductility ratios adopted as damage criteria are not appropriate for either the design or damage assessment of blast resistant steel columns, and that the current approach could be a much more appropriate alternative.

• Earthquakes and Structures
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• 제9권5호
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• pp.1045-1067
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• 2015

A performance-based design (PBD) procedure, initially proposed for the seismic design of buildings, is tailored herein to the structural configurations commonly adopted in bridges. It aims at the efficient design of bridges for multiple performance levels (PLs), achieving control over a broad range of design parameters (i.e., strains, deformations, ductility factors) most of which are directly estimated at the design stage using advanced analysis tools (a special type of inelastic dynamic analysis). To evaluate the efficiency of the proposed design methodology, it is applied to an actual bridge that was previously designed using a different PBD method, namely displacement-based design accounting for higher mode effects, thus enabling comparison of the alternative PBD approaches. Assessment of the proposed method using nonlinear dynamic analysis for a set of spectrum-compatible motions, indicate that it results in satisfactory performance of the bridge. Comparison with the displacement-based method reveals significant cost reduction, albeit at the expense of increased computational effort.

• Smart Structures and Systems
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• 제10권2호
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• pp.89-110
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• 2012

This study was intended to efficiently perform the probabilistic optimal safety assessment of steel cable-stayed bridges (SCS bridges) using stochastic finite element analysis (SFEA) and expected life-cycle cost (LCC) concept. To that end, advanced probabilistic finite element algorithm (APFEA) which enables to execute the static and dynamic SFEA considering aleatory uncertainties contained in random variable was developed. APFEA is the useful analytical means enabling to conduct the reliability assessment (RA) in a systematic way by considering the result of SFEA based on linearity and nonlinearity of before or after introducing initial tensile force. The appropriateness of APFEA was verified in such a way of comparing the result of SFEA and that of Monte Carlo Simulation (MCS). The probabilistic method was set taking into account of analytical parameters. The dynamic response characteristic by probabilistic method was evaluated using ASFEA, and RA was carried out using analysis results, thereby quantitatively calculating the probabilistic safety. The optimal design was determined based on the expected LCC according to the results of SFEA and RA of alternative designs. Moreover, given the potential epistemic uncertainty contained in safety index, failure probability and minimum LCC, the sensitivity analysis was conducted and as a result, a critical distribution phase was illustrated using a cumulative-percentile.

• Steel and Composite Structures
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• 제23권2호
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• pp.205-215
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• 2017

The use of advanced fibre composite materials in bridge engineering offers alternative solutions to structural problems compared to traditional construction materials. Advanced composite or fibre reinforced polymer (FRP) materials have high strength to weight ratios, which can be especially beneficial where dead load or material handling considerations govern a design. However, the reduced weight and stiffness of FRP footbridges results in generally poorer dynamic performance, and vibration serviceability is likely to govern their design to avoid the footbridge being "too lively". This study investigates the dynamic behaviour of the 51.3 m span Wilcott FRP suspension footbridge. The assessment is performed through a combination of field testing and finite element analysis, and the measured performance of the bridge is being used to calibrate the model through an updating procedure. The resulting updated model allowed detailed interpretation of the results. It showed that non-structural members such as the parapets can influence the dynamic behaviour of slender, lightweight footbridges, and consequently their contribution must be included during the dynamic assessment of a structure. The test data showed that the FRP footbridge is prone to pedestrian induced vibrations, although the measured response levels were lower than limits specified in relevant standards.

• 한국태양에너지학회 논문집
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• 제23권1호
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• pp.57-67
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• 2003

This study aims to presents Evaluation Method of Green Remodeling that analyze the value of environment through expense, using the method of life cycle cost and life cycle assessment simultaneously. The results of this study are summarized as follows. Evaluation Model developed in this study can convert economical value of environment into cost by integrating. In addition, the model can apply as a useful tool to estimation of economical design alternative as well as quantification of environmental loads and costs. Evaluation Model presented In this study observe energy consumption and the environmental load emission with qualification, it can forecast effect of environmental cost that cost estimation is expected to be added to energy cost rate by being possible. Synthetically, when Estimation Model and computer program that developed in this study is applies to the construction industry; reasonable management of environmental load is convenient at each step of Green Remodeling. In addition, at preliminary design phase, practical use may be possible by reasonable yardstick about various alternatives and improvement of design alternatives likewise by grasping environmental effect.

• 한국태양에너지학회 논문집
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• 제35권1호
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• pp.53-60
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• 2015

The ECO2 building energy simulation program is used on the assessment project for building energy certification of non-dwelling buildings in Korea. In the design of energy efficient buildings, it is beneficial to identify the most important design parameters in oder to more efficiently develop alternative design solutions or reach optimized design solutions. The sensitivity analyses will be used at a reasonable early stage of the building design process, where it is still possible to influence the most important design parameters. In this study, the sensitivity analysis is focused on building envelope parameters such as U-values, SHGC and Wall-window ration.

• Environmental Analysis Health and Toxicology
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• 제30권sup호
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• pp.7.1-7.10
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• 2015

Objectives For successful adoption of legislation controlling registration and assessment of chemical substances, it is important to obtain sufficient toxicological experimental evidence and other related information. It is also essential to obtain a sufficient number of predicted risk and toxicity results. Particularly, methods used in predicting toxicities of chemical substances during acquisition of required data, ultimately become an economic method for future dealings with new substances. Although the need for such methods is gradually increasing, the-required information about reliability and applicability range has not been systematically provided. Methods There are various representative environmental and human toxicity models based on quantitative structure-activity relationships (QSAR). Here, we secured the 10 representative QSAR-based prediction models and its information that can make predictions about substances that are expected to be regulated. We used models that predict and confirm usability of the information expected to be collected and submitted according to the legislation. After collecting and evaluating each predictive model and relevant data, we prepared methods quantifying the scientific validity and reliability, which are essential conditions for using predictive models. Results We calculated predicted values for the models. Furthermore, we deduced and compared adequacies of the models using the Alternative non-testing method assessed for Registration, Evaluation, Authorization, and Restriction of Chemicals Substances scoring system, and deduced the applicability domains for each model. Additionally, we calculated and compared inclusion rates of substances expected to be regulated, to confirm the applicability. Conclusions We evaluated and compared the data, adequacy, and applicability of our selected QSAR-based toxicity prediction models, and included them in a database. Based on this data, we aimed to construct a system that can be used with predicted toxicity results. Furthermore, by presenting the suitability of individual predicted results, we aimed to provide a foundation that could be used in actual assessments and regulations.

• 한국조경학회지
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• 제47권5호
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• pp.1-13
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• 2019

본 연구는 유아의 설계참여를 통하여 유아 선호에 부합하는 유아숲체험원 설계안을 도출하는 것에 목적이 있으며, 이를 위해 유아 참여설계에 대한 전체과정을 대상지 인지단계, 계획요소 도출단계, 설계안 도출단계로 구축하였다. 본 연구에서는 설계안 도출 단계를 광주광역시 광산구에 위치한 '송산물빛유아숲체험원'과 K유치원(6, 7세 통합반; 전체 41명) 유아를 대상으로 진행하였다. 설계안 도출을 위해 3회의 설계과정(유아 참여과정 2회, 연구자 분석과정 1회)과 과정별 도구구축, 유아 참여 워크숍을 진행하였다. 연구결과, 첫째, 유아워크숍을 통한 유아의 설계안은 총 41개안으로, 유아 1명이 평균 7.66개소의 공간을 그렸다. 6세 남아가 가장 적게(평균 6.80개소), 7세 여아가 가장 많게(평균 9.0개소) 설계하였다. 전체, 성별, 나이별 모두 신체 및 모험놀이공간을 가장 많이(38.9%~48.7%) 설계하였다. Base map을 활용한 유아설계의 가능성 분석을 위해 41개의 설계안에서 대상지 내 물리적 환경특성(7개 항목)의 출현 여부를 분석하였다. 그 결과, 전체적으로 72번의 환경특성이 나타났고, 이러한 환경특성은 87.8%(26개안)의 설계안에서 1개 항목 이상 나타났다. 둘째, 설계대안으로 APS type(동적 놀이시설공간 집중배치) 15개 안, NS type(자연공간 위주 설계) 14개 안, SPS type(정적 놀이시설공간 위주 설계) 12개의 안의 3개 유형이 도출되었다. 셋째, 설계대안별 선호도(5점 척도) 평가와 3개 유형의 대안 비교평가를 통해 최종 선정된 NS type은 자연공간(숲공간, 숲길, 쉼터, 자연탐색공간, 생태연못)이 주요 공간으로 설계되었고, 동적놀이시설공간, 물놀이 공간, 흙(모래)놀이 공간 등이 적정한 양으로 배치되어 인지적 발달놀이(기능놀이, 구조놀이, 극(상징)놀이) 모두가 충분히 발현될 수 있는 설계안으로 판단된다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제4권2호
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• pp.141-150
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• 2012

Ship damage caused by maritime casualties leads to marine pollution and loss of life and property. To prevent serious damage from maritime casualties, several types of safety regulations are applied in ship design. Damage stability regulation is one of the most important safety issues. Designs of ships for long international voyages must comply with these regulations. Current regulations, however, do not consider the characteristics of the operating route of each ship and reflect only ship size and type of cargo. In this paper, a damage safety assessment was undertaken for a ship carrying radioactive waste in actual wave conditions. Damage cases for safety assessment were constructed on the basis of safety regulations and related research results. Hull form, internal arrangement, loading condition and damage condition were modeled for damage safety simulation. The safety simulation was performed and analyzed for 10 damage cases with various wave heights, frequency and angle of attack on an operating route. Based on evaluation results, a design alternative was generated, and it was also simulated. These results confirmed that damage safety analysis is highly important in the design stage in consideration of the operating route characteristics by simulation. Thus a ship designer can improve safety from damage in this manner.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.656-661
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• 2009

In this study, theoretical analysis and evaluation tests were performed to assess the pipe stability against compaction equipments and vehicle loads when conventional construction criteria for pre-insulation heating pipes are applied and the alternative material, crushed sand, are used for backfills. The research outcomes shows that (1) the conventional code criteria for pre-insulated heating pipes is well established to support compaction equipments and vehicle loads, (2) the crushed sands as an alternative is usable as backfill materials for pre-insulated heating pipes based on the suitability evaluations of various types of pipes, and (3) the crushed sand agree well with the design consideration of pre-insulated heating pipes construction in the points of economical efficiency and construction criteria.