• Structural Engineering and Mechanics
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• v.61 no.1
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• pp.161-169
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• 2017

This study aimed to develop a simple and effective method to facilitate the experimental research on mechanical properties of masonry under biaxial compressive stress. A series of tests on full-scale brick masonry panels under biaxial compression have been performed in limited principal stress ratios oriented at various angles to the bed joints. Failure modes of tested panels were observed and failure features were analyzed to reveal the mechanical behavior of masonry under biaxial compression. Based on the experimental data, the failure curve in terms of two orthotropic principal stresses has been presented and the failure criterion of brick masonry in the form of the tensor polynomial has been established, which indicate that the anisotropy for masonry is closely related to the difference of applied stress as well as the orientation of bed joints. Further, compared with previous failure curves and criteria for masonry, it can be found that the relative strength of mortar and block has a considerable effect on the degree of anisotropy for masonry. The test results demonstrate the validity of the proposed experimental method for the approximation of masonry failure under biaxial compressive stress and provide valuable information used to establish experimentally based methodologies for the improvement of masonry failure criteria.

• Journal of Korean Institute of Industrial Engineers
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• v.24 no.4
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• pp.627-638
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• 1998

For any hazardous operation or risky project to be carried out safely and economically, it is of the utmost importance to formulate proper risk management policies based on the rational assessment of the risk levels of various potential hazards. In this paper, a Fuzzy Multi-Criteria Decision Making(FMCDM) method for risk assessment is proposed. The method evaluates, on the basis of fuzzy set theory, the risk level of a risky situation by aggregating the assessed levels of risk factors and their subjective weights. The method also allows some flexibility for the future users in the sense that, first, the relative importance weights for the three risk factors can be adjusted according to the nature of projects or systems and, second, the users have the choice between the two types of risk assessment results, that is, the assessed risk levels or the ranks of the risk situations. A numerical example for the proposed FMCDM method is provided to illustrate the computational procedure. To see how the suggested FMCDM method describes well people's perceived risk level, we compared the risk values derived from the suggested method with the subjective risk evaluations for ten risky situations.

• Journal of Navigation and Port Research
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• v.31 no.9
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• pp.801-806
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• 2007

The analytical hierarchy process (AHP) enables decision makers to represent the interaction of multiple factors in complex and unstructured situations. The process requires the decision maker to develop a hierarchical structure of the factors in the given problem and to provide judgments about the relative importance of each of these factors and ultimately to specify a preference for each decision alternative with respect to each factor. The research presented in this paper applies the AHP to identify key players in promoting port competitiveness. The literature survey revealed four major criteria and 15 sub-criteria. The four factors are cost, service quality, facility/capacity and economic-social variable. 150 questionnaires suitable for AHP analysis were made and 77 were returned. It is found that in terms of cost, the first key player is terminal operator and the second key player is shipping companies calling Busan port; in terms of service quality, the first key player is terminal operator, and the second key player is shipping companies calling Busan port; in terms of facility/capacity, the first key player is port authority and the second key player is terminal operator; in terms of economic-social variable, the first key player is terminal operator, and the second key player is shipping companies calling Busan port.

• International Journal of Highway Engineering
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• v.16 no.1
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• pp.111-118
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• 2014

PURPOSES : This study performs fundamental research on ramp-metering design criteria. METHODS : We carefully review previous studies in terms of ramp-metering design criteria and then consider applicability in Korea. For this, traffic simulation model is employed to analyze actual effect according to specific location of stop-line when implementing ramp-metering. RESULTS : When a stop-line moving forward with a 50m interval, travel speed at mainline relative to current stop-line location tends to decrease. However, traveling speed at approach roads increase about 5~18% under the same condition. When a stop-line location moving backward with a 50m interval, mainline travel speed increase approximately 17~32% whereas traveling speed at approach roads decrease. All cases are compared with the current stop-line location. CONCLUSIONS : We believe that both cases are useful with respect to freeway management. For example, moving forward a stop-line case can be used management for queuing area at ramp section and approach roads. Moving backward a stop-line case can be used for traffic control, focusing on mainline of freeways.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.17 no.1
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• pp.47-58
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• 2019

The paper presents the results of a multi-criteria comparative evaluation of 12 feasible Russian nuclear energy deployment scenarios with thermal and fast reactors in a closed nuclear fuel cycle. The comparative evaluation was performed based on 6 performance indicators and 5 different MCDA methods (Simple Scoring Model, MAVT / MAUT, AHP, TOPSIS, PROMETHEE) in accordance with the recommendations elaborated by the IAEA/INPRO section. It is shown that the use of different MCDA methods to compare the nuclear energy deployment scenarios, despite some differences in the rankings, leads to well-coordinated and similar results. Taking into account the uncertainties in the weights within a multi-attribute model, it was possible to rank the scenarios in the absence of information regarding the relative importance of performance indicators and determine the preference probability for a certain nuclear energy deployment scenario. Based on the results of the uncertainty/sensitivity analysis and additional analysis of alternatives as well as the whole set of graphical and attribute data, it was possible to identify the most promising nuclear energy deployment scenario under the assumptions made.

• Cross-Cultural Studies
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• v.25
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• pp.7-33
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• 2011

In this paper we attempt to read a film by Haejoon LEE entitled 'Castaway on the moon' from the Bauman's modernity perspective that draws our attention to uncomfortable problems relative to wastes and wasted lifes in the global consumer society we all live in. The so-called consumer society is a post-modern society designed according to the following two criteria: on the one hand, beauty and ugliness and on the other hand, competence and incompetence. Classified as ugly as well as incompetent in this society, the two heros in this film are condemned to live their lifes isolated. Miss Kim is confined to her small room while Mr. Kim is exiled to an uninhabited island called 'Bamsum' in the Han River. In these spaces, neither inside nor outside, they perform what we would like to call 'surplus act', using wastes at their disposal. In this paper we ask ourselves whether or not this act is able to challenge the two criteria and the solidarity of the two wasted lifes can bring about change in the consumer oriented society. As well as Bauman, Agamben will help us approach this question from a theoretical point of view.

• Journal of the Korea Safety Management & Science
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• v.22 no.4
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• pp.87-100
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• 2020

Economic Development Zone(EDZ) in the province is one of the foreign policy for economic development of North Korea. North Korea has promulgated 27 Economic Development Zones(5 EDZs as central level and 22 EDZs as provincial level) to promote economic growth through the expansion of external opening policy. EDZs of the provinces play an important role in North Korea's national and regional economic growth. The purpose of this study is to select analytical criteria that can be quantified when considering the location conditions of North Korean economic development zones when domestic companies advance into North Korea according to the progress of inter-Korean economic cooperation, and derive the relative importance between the criteria. After that, based on this, we intend to quantify the evaluation of the location priority of the economic development zone. In this study, through AHP analysis results, when domestic companies enter North Korea, we derive the importance and preference of location selection factors when considering the location conditions of North Korean economic development zones. Taking into account the reality of North Korea when the Korean company entered the North economic development zone following location for evaluation. That is, logistics and transportation, industrial infrastructure, competitiveness, and management incentives. And 14 sub-factors were selected and AHP analysis was performed.

• Journal of Aerospace System Engineering
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• v.16 no.5
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• pp.35-42
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• 2022

This paper deals with predicting comparable mechanical properties of laminated composite plates. The stiffness of an equivalent anisotropic composite plate is derived based on classical lamination theory. A novel failure criterion is defined to describe the failure behaviour of laminated composite plates based on micro-mechanics failure criteria. Finally, the theory's validation of finite element analysis results was verified. We concluded that this theory is very suitable for failure analysis of laminated composite plates for aerospace applications due to their relative simplicity and computational efficiency.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.308-314
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• 2013

Although global construction spending has experienced slow growth due to consecutive economic crises, global contractors have consistently attempted to expand their overseas market share, leading to more intense competition among contractors in the international construction market. In this market environment, owners, clients and financial institutions require reasonable and systematic criteria to effectively assess the business capabilities of international construction firms. However, the existing evaluation methods for construction firms rarely consider overseas-focused business capabilities. To address this problem, this study proposes a quantitative approach to assessing the overseas business capabilities of international construction firms. The limitations of existing approaches are reviewed, and the capabilities required to perform overseas businesses are analyzed through expert interviews. Finally, 18 evaluation indices are suggested in four categories: technology resources, project management, experience and performance, and sustainability. The relative weight of each index is determined according to the Analytical Hierarchy Process (AHP) method, and a preliminary investigation of 11 Korean construction firms is conducted. The proposed method is expected that it will provide the rational criteria for international owners, clients, and financial institutions for decision-making and for evaluating international contractors.

• Earthquakes and Structures
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• v.27 no.4
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• pp.285-302
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• 2024

Conducting nonlinear pushover analysis typically demands intricate and resource-intensive computational efforts, involving a highly iterative process necessary for meeting both design-defined and requirements of codes in performance-based design. This study presents a computer-based technique for reinforced concrete (RC) buildings, incorporating optimization numerical approaches, optimality criteria and pushover analysis to automatically enhance seismic design performance. The optimal design of concrete beams, columns and shear walls in concrete frames is presented using the artificial bee colony optimization algorithm. The methodology is applied to three frames: a 4-story, an 8-story and a 12-story. These structures are designed to minimize overall weight while satisfying the levels of performance including Life Safety (LS), Collapse Prevention (CP), and Immediate Occupancy (IO). The process involves three main steps: first, optimization codes are implemented in MATLAB software, and the OpenSees software is used for nonlinear static analysis. By solving the optimization problem, several top designs are obtained for each frame and shear wall. Pushover analysis is conducted considering the constraints on relative displacement and plastic hinge rotation based on the nonlinear provisions of the FEMA356 nonlinear provisions to achieve each level of performance. Subsequently, convergence, pushover, and drift history curves are plotted for each frame, and leading to the selection of the best design. The results demonstrate that the algorithm effectively achieves optimal designs with reduced weight, meeting the desired performance criteria.