• Journal of Korean Society for Quality Management
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• v.30 no.4
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• pp.106-119
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• 2002

The fatigue curve with estimated parameters represents the estimate of the median or mean life at a given applied stress But, in order to assist a designer in making decisions regarding the fatigue failure mode, it is common practice to construct a design curve on the lower or safe side of data. In this study, to overcome the limitations(i.e., no runout, equal variance, and quality of the approximation, etc) of Shen, Wirsching, and Cashman's method which suggested the approximate design curve for nonlinear models using tolerance interval constructed by Owen's method, an algorithm to find design curves under the fatigue model using a parametric bootstrap method, is proposed and illustrated with multiple fatigue data sets.

• Geomechanics and Engineering
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• v.22 no.5
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• pp.433-439
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• 2020

Tunnels are one of the most important constructions in civil engineering. The damage to these structures caused enormous costs. Therefore, the safe and economic design of these structures has long been considered. However, both applied loads on the tunnels as well as the resistance of the structural members are naturally uncertain parameters, hence, the design of these structures requires considering the probabilistic approaches. This study aims to determine the load and resistant factors of lining tunnels concerning the earthquake extreme events limit state function. For this purpose, tunnels that have been designed according to the previous design codes (AASHTO Tunnel LRFD 2017) and using reliability analysis, the optimum reliability of these structures for different loading scenarios is determined. In this paper, the tunnel is considered circular. Finally, the proper load and resistance factors are calculated corresponding to the obtained target reliability. Based on the performed calibration earthquake extreme events limit state function, the result of this study can be recommended to AASHTO Tunnel LRFD 2017.

• Fire Science and Engineering
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• v.28 no.4
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• pp.50-56
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• 2014

The quantification of fire size in buildings must be preceded in order to design the trial of performance based design (PBD). When design fire size is determined appropriately, the trial design will become economical and safe design against fire risk. There are many problems in determining design fire size because of lacks of fire engineering data and short history of PBD in korea. Therefore, this paper has surveyed the guideline of design fire in other countries, real experimental data for a few occupancies and the cases of design fire size determining for PBD in Korea. Also, it has proposed the guideline of design fire size for various occupancies in korea after analyzing the appropriateness of design fire size.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.5
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• pp.415-425
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• 2017

Stresses occur in the spent nuclear fuel disposal canister due to the impulsive forces incurred in the accidental drop and impact event from the transportation vehicle onto the ground during deposition in the repository. In this paper, the comparative study of finite element analysis for stresses occurring in various models of the spent nuclear fuel disposal canister due to these impulsive forces is presented as one of design processes for the structural integrity of the canister. The main content of the study is about the design of the structurally safe canister through this comparative study. The impulsive forces applied to the canister subjected to the accidental drop and impact event from the transportation vehicle onto the ground in the repository are obtained using the commercial rigid body dynamic analysis computer code, RecurDyn. Stresses and deformations occurring due to these impulsive forces are obtained using the commercial finite element analysis computer code, NISA. The study for the structurally safe canister is carried out thru comparing and reviewing these values. The study results show that stresses become larger as the wall encompassing the spent nuclear fuel bundles inside the canister becomes thicker or as the diameter of the canister becomes larger. However, the impulsive force applied to the canister also becomes larger as the canister diameter becomes larger. Nonetheless, the deformation value per unit impulsive force decreases as the canister diameter increases. Therefore, conclusively the canister is structurally safe as the diameter increases.

• Ocean Systems Engineering
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• v.1 no.2
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• pp.157-169
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• 2011

To provide more rational design solutions at conceptual design level, axiomatic design method has been applied to solve critical part of a new engineering problem called Mobile Harbor. In the implementation, the Mobile Harbor, a functional harbor system that consists of a vessel with container crane approaches to a container ship anchored in the open sea and establishes a secure mooring between the two vessels to carry out loading and unloading of containers. For this moving harbor system to be able to operate successfully, a reliable and safe strategy to moor and maintain constant distance between the two vessels in winds and waves is required. The design process of automatic ship-to-ship mooring system to satisfy the requirements of establishing and maintaining secure mooring has been managed using axiomatic design principles. Properly defining and disseminating Functional Requirements, clarifying interface requirements between its subsystems, and identifying potential conflict, i.e. functional coupling, at the earliest stage of design as much as possible are all part of what need to be managed in a system design project. In this paper, we discuss the automatic docking system design project under the umbrella of KAIST mobile harbor project to illustrate how the Axiomatic Design process can facilitate design projects for a large and complex engineering system. The solidified design is presented as a result.

• Korean Institute of Interior Design Journal
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• v.15 no.3 s.56
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• pp.48-55
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• 2006

A sustainable building must produce an interior environment that is safe, healthy, comfortable and supportive of human performance and well-being. The medical human comfort: performance and productivity cost of unhealthy environment may cause much cost for healing. Research that buildings with daylight, fresh air, eco-materials and sustainable interior design are consistently rated as more comfortable and occupants performance, satisfaction and health. This study is to categorize systematically interior environmental design elements for improving sustainability with a view to developing an evaluation model of super high-rise apartment unit plans. With a literature survey and design guide lines concerning sustainable design elements, three hierarchical categorization levels of human, environment, energy and resources systems that consists of upper, middle, low design elements have been proposed. A total of 6 items have been suggested for middle level of categorization and 24 items for lower level. Finally a total of 107 design elements concerning the 24 items and their relationahips have been revealed. The needs for a systematic approach to interior environmental design for sustainability have been discussed.

• Journal of The Korea Institute of Healthcare Architecture
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• v.24 no.4
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• pp.59-67
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• 2018

Purpose: The concept of the Barrier-Free Design has steadily expanded into a basic principle of design, which can provide safe and convenient lives not only limited to the disables, elders, and pregnant women, but also to all members of the society. This is what we now know as the Universal Design. In other words, Barrier-Free Design for all is Architectural Approach of Universal Design. Thus, as a future-oriented alternative to school facilities according to social change, this study suggests basic direction of school building planning and concept of universal design considering school facilities characteristics. Methods: The characteristics of school facilities are understood from the perspective of Universal Design. In addition, a survey is conducted to identify the current state of school facilities. Result: Findings from this study are as follows. First, Universal Design of School Building is an integrated characteristic. Integration is intended to create and manage an integrated environment instead of an individual and one-time approach to installation and maintenance of convenience facilities. Second, It is a flexible characteristic to be sustainable. In other words, they aim to be selectable to respond to change. Third, It is a characteristic of accumulation of outstanding cases. This means that not only individual schools but also entire school spaces will be applied to Universal Design to form a virtuous circle of environment improvement. Implications: The results of this study may serve as a basic concept in the design of school buildings.

• Korean Institute of Interior Design Journal
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• v.24 no.6
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• pp.137-144
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• 2015

Light was the symbol of the city's prosperity and culture. People can walk around the city at the night time with safe. Now light is used with beauty and function at the same time. This study is the example how to draw the lighting design concept in specific city and district based on the citizen-minded survey. The citizen-minded survey makes a new chance taking the goodness and characteristics from local city specially and select the site for applying the specific opinion and requirement in the city. The expression of design concept on night landscape design gives the fresh image to the city during the night time. Because people feel the free and dynamic mood in the night landscape lighting, it is very important to set and express the design concept on night landscape design. The result of this study was applied in the Daegu city. In particular, the distribution complex's night landscape lighting in the Daegu was designed with specific concept expression from the citizen-minded survey. Making and expressing the design concept on night landscape design is basic for unity and diversity in the city.

• Journal of Ocean Engineering and Technology
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• v.30 no.1
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• pp.10-17
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• 2016

This paper reports a simulation-based design method for the optimized arrangement design of buoyancy modules in a marine riser system. A buoyancy module is used for the safe operation and structural stability of the riser. Engineers design buoyancy modules based on experience and experimental data. However, they are difficult to design because of the difficulty of conducting real sea experiments and quantifying the data. Therefore, a simulation-based design method is needed to tackle this problem. In this study, we developed a simulation-based design algorithm using a multi-body dynamic simulation and genetic algorithm to perform optimization arrangement design of a buoyancy module. The design results are discussed in this paper.

• Nuclear Engineering and Technology
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• v.55 no.6
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• pp.2047-2052
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• 2023

Risk-informed approach has been widely applied in the safety design, regulation, and operation of nuclear reactors. It has been commonly accepted that risk-informed design optimization should be used in the innovative reactor designs to make nuclear system highly safe and reliable. In spite of the risk-informed approach has been used in some advanced nuclear reactors designs, such as Westinghouse IRIS, Gen-IV sodium fast reactors and lead-based fast reactors, the process of risk-informed design of nuclear reactors is hardly to carry out when passive system reliability should be integrated in the framework. A practical method for new passive safety reactors based on probabilistic safety assessment (PSA) and passive system reliability analyze linking is proposed in this paper. New three-dimension frequency-consequence curve based on risk concept with three variables is used in this method. The proposed method has been applied to the determination optimization of design options selection in a 10 MWth lead-based research reactor(LR) to obtain one optimized system design in conceptual design stage, using the integrated reliability and probabilistic safety assessment program RiskA, and the computation resources and time consumption in this process was demonstrated reasonable and acceptable.