• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.773-776
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• 2004

The so-called Life Cycle Cost (LCC) analysis on reinforced concrete bridge can provide useful information for initial design and maintenance plan of the RC bridge. This paper proposes an LCC prediction equation and a sensitivity analysis method for RC bridges. An LCC equation for the RC bridge which includes initial investment cost, maintenance cost, and demolition cost was derived and verified from the data for design and construction of an RC slab bridge. In order to solve uncertainty problem on actual discount rate and material characteristics in the analysis of LCC of concrete bridges, a sensitivity analysis method on the LCC using the Monte Carlo simulation technique was suggested.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2008.05a
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• pp.163-168
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• 2008

In a today, our concerns have been changed from a single material to relation, communication and time. The human life made up of science, technology, philosophy and art of the modern society can decide whoerness by connecting or replacing a comprehensive and many kinds. This one is exhibited in interior actively. The space of the pluralistic world is sustained by not simple and fixed relation but complex and flexible relation. And it is shown as an undecided phenomenon by effecting and modifying each other. In here, the boundary has a phase of undecided relation but at the same time it can make possibility to be abundant to infinity. The purpose of our study with considering the uncertainty of the boundary is to solve the discord of between division and unify of modern architecture space and suggest new way to be mediation and to occupy independent area.

• Earthquakes and Structures
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• v.10 no.3
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• pp.629-643
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• 2016

Among all the natural disasters, earthquakes are the most destructive calamities since they cause a plenty of injuries and economic losses leaving behind a series of signs of panic. The present study highlights the moment-curvature relationships for the structural elements such as beam and column elements and Non-Linear Static Pushover Analysis of RC frame structures since it is a very simplified procedure of non-linear static analysis. The highly popular model namely Mander's model and Kent and Park model are considered and then, seismic risk evaluation of RC building has been conducted using SAP 2000 version 17 treating uncertainty in strength as a parameter. From the obtained capacity and demand curves, the performance level of the structure has been defined. The seismic fragility curves were developed for the variations in the material strength and damage state threshold are calculated. Also the comparison of experimental and analytical results has been conducted.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.2
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• pp.177-186
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• 2021

Radioactive materials from nuclear power facilities can be released into the atmosphere through various channels. Recently, the dispersion of radioactive materials has become critical issue in Korea after Kori Unit 1 and Wolsong Unit 1 were permanently shut down. In this study, annual atmospheric dispersion factors were compared based on the continuous release and purge release using the XOQDOQ computer program, a method for calculating atmospheric dispersion factors at commercial nuclear power stations. The meteorological data analyzed in this study was based on the Shin Kori nuclear power meteorological tower which has the largest operating nuclear power plants in Korea, for three years (from 2008 to 2010). The analysis results of the dispersion factor of the radioactive material release obtained using the XOQDOQ program showed that the difference between the continuous release and purge release was within two times. This study will be valuable helpful for revealing the uncertainty of the predictive atmospheric dispersion factor to achieve regulation.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1474-1478
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• 2009

The cooperation and trust among the project participants play a critical role in the success or failure of any delivery system in construction industry. But it is very difficult to establish trust between an owner and a contractor when rational people only pursue only their own material self-interest. Based on the principal-agent theory, this paper will introduce the altruistic behavior into the traditional principal-agent model, and model the reciprocal behavior between the owner and contractor. We will show that both the owner and the contractor benefit from their reciprocal behavior, and hence trust establishing between them is possible. More importantly, we will proof that the higher the project uncertainty is, the more important trust establishing is.

• Coupled systems mechanics
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• v.11 no.5
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• pp.411-438
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• 2022

In this paper, we present the parameter identification for inelastic and multi-scale problems. First, the theoretical background of several fundamental methods used in the upscaling process is reviewed. Several key definitions including random field, Bayesian theorem, Polynomial chaos expansion (PCE), and Gauss-Markov-Kalman filter are briefly summarized. An illustrative example is given to assimilate fracture energy in a simple inelastic problem with linear hardening and softening phases. Second, the parameter identification using the Gauss-Markov-Kalman filter is employed for a multi-scale problem to identify bulk and shear moduli and other material properties in a macro-scale with the data from a micro-scale as quantities of interest (QoI). The problem can also be viewed as upscaling homogenization.

• Computational Structural Engineering
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• v.5 no.1
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• pp.97-108
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• 1992

This paper is an attempt to account for the uncertainty of the residual strength in the reliability analysis of structural systems. For this purpose the stochastic finite element method(SFEM) is linked to the system reliability analysis procedure. The stochastic finite element is known to be able to a more explicitly consider the effect of uncerainties of material and geometric variables on those of load effects in structural analysis procedure. The method has been applied to system as well as component reliability analysis of a plane structure. Comparison of the results by the present approach is made with the method in which the residual strength of failed component is treated as deterministic variable. Several case studies have been carried to show the effect of uncertainty in residual strength of a member after failure. Is has been conformed that reidual strength very much affect the system reliability level. It can be, hence, concluded that the uncertainties in the post-ultirnate behaviour may have to be taken into account in the system reliability analysis for a better a ssessment of the system reliability especially for a structure of which member behaviour is modelled as asemi-brittle model. And then the stochastic finite element method can efficiently evaluate the system reliability.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.3
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• pp.109-117
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• 2016

Recently, corporate environment is faced with uncertainty that did not suffer in the past. In addition, as the supply chain was expanded and lengthened, the flow of information and material was complicated. Increase in complexity which amplifies the variability of the individual steps in supply chains further adds to the uncertainty. The bullwhip effect that refers the phenomenon where order variability increases as the orders move upstream in the supply chain became serious. The bullwhip effect is more and more important especially for the enterprise in the supply chain. So, there are many studies now since it was observed about 100 years ago. The aim of this paper is to analyze how to solve the bullwhip effect by using TRIZ (Teoriya Resheniya Izobretatelskikh Zadach). TRIZ is one of the most famous tools for creative solving that applied in many fields ranging from management as well as engineering. Among problems, the dilemma needs creative solutions that require handling the contradictions inherent in that. Among various kinds of problem solving techniques, TRIZ provides the concept of physical contradiction as a common problem solving principle. This study provides a simple process of solving problem explains a case of solving problem in the management field and shows the availability of theory in the inventory control. In accordance with the proposed solving process, the paper analyzes the bullwhip effect by applying the TRIZ tools and then identifies the solution directions. Next, the current studies are classified by the above analysis and important managerial concepts are proposed. Lastly, directions for future research on this area are suggested.

• Journal of Korean Library and Information Science Society
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• v.36 no.2
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• pp.283-305
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• 2005

Data produced during scientific and technical activities usually have value as standard reference data (SRD) which is a well-documented numeric value assessed for reliability and accuracy. The main criteria in the evaluation for SRD is how well their production is documented including a sample preparation, measurement method, data processing and so on, other than reference data. SRD is represented as a certified numeric value with uncertainty. In this study, the SRD in the area of material properties was introduced to provide understanding of SRD and its evaluation method. Also the national SRD system was studied. The national SRD system is composed of the center for the SRD, the data centers, and the committee. The role and task of those components were studied. The legislational and systematic supports for the system were proposed in this study.

• Composites Research
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• v.26 no.1
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• pp.29-35
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• 2013

Composite sandwich structure can improve the specific bending stiffness significantly and save the weight nearly 30 percent compared with the composite laminates. However, it has more inherent uncertainties of the material property caused by manufacturing process than metals. Therefore, the reliability-based probabilistic design approach is required. In this paper, the PMS(Probabilistic Margin of Safety) is calculated for the simplified fuselage structure made of composite sandwich to provide the probabilistic reasonable evidence that the classical design method based on the safety factor cannot ensure the structural safety. In this phase, the probability density function estimated by CMCS(Crude Monte-Carlo Simulation) is used. Furthermore, the RBDO(Reliability-Based Design Optimization) under the probabilistic constraint are performed, and the RBDO-MPDF(RBDO by Moving Probability Density Function) is proposed for an efficient computation. The examined results in this paper can be helpful for advanced design techniques to ensure the reliability of structures under the uncertainty and computationally inexpensive RBDO methods.