• Journal of Electrical Engineering and Technology
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• v.1 no.4
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• pp.448-454
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• 2006

As the power industry moves towards open competition, a need has arisen for appropriate methodology to evaluate power system reliability by using customer Interruption costs. This paper presents an assessment of the interruption costs by industrial customer type in Korea using customer survey methodology. When various research results are examined, the customer damage survey methodology becomes much more generalized. Especially, in the case of industrial customers, it is known that evaluation by the customer damage survey is more useful. Accordingly, this paper selected the customer damage survey method to evaluate the interruption costs by industrial customer type in Korea considering interruption and customer characteristics.

• Nuclear Engineering and Technology
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• v.54 no.3
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• pp.917-925
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• 2022

Steam generator (SG) tubes in a nuclear power plant can undergo rapid changes in pressure and temperature during an accident; thus, an accurate model to predict short-term creep damage is essential. The theta (𝜃) projection method has been widely used for modeling creep-strain behavior under constant stress. However, many creep test data are obtained under constant load, so creep rupture behavior under a constant load cannot be accurately simulated due to the different stress conditions. This paper proposes a novel methodology to obtain the creep curve under constant stress using a modified 𝜃 projection method that considers the increase in true stress during creep deformation in a constant-load creep test. The methodology is validated using finite element analysis, and the limitations of the methodology are also discussed. The paper also proposes a creep-strain model for alloy 690 as an SG material and a novel creep hardening rule we call the damage-fraction hardening rule. The creep hardening rule is applied to evaluate the creep rupture behavior of SG tubes. The results of this study show its great potential to evaluate the rupture behavior of an SG tube governed by creep deformation.

• Journal of Korea Technology Innovation Society
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• v.14 no.spc
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• pp.1073-1095
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• 2011

Recently, technology intelligence (TI) activities that support technological and/or market innovation have been important for many organizations to develop their competitiveness in trend of strengthening innovation-led economy. It is required to thorough understanding of TI-related activities and investigating methodology that can support these activities to facilitate technology opportunity exploration activities and increase the possibility of innovation. Thus, this research aims at first, investigating the taxonomy of objectives, information and methodology for technology opportunity development (TOD) through literature survey, second, deriving the TOD needs and current status analysis by conducting interview with various domestic firms, and finally, proposing an integrated framework of TI by synthesizing the results of the aforementioned investigation. Therefore, this research can suggest the strategic and political implications on TOD activities and moreover, propose a theoretical foundation to develop a supporting system for TI.

• Journal of the Ergonomics Society of Korea
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• v.32 no.2
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• pp.179-187
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• 2013

Objective: The purpose of this study is to extract GOMS manual operator, except for an experiment with participants. Background: The GOMS model has advantage of rapid modeling which is suitable for the environment of technology development which has a short life cycle products with a fast pace. The GOMS model was originally designed for desktop environment so that it is not adequate for implementing into the latest HCI environment such as small touch screen device. Therefore, this research proposed GOMS manual operator extraction methodology which is excluded experimental method. And flick Gesture was selected to explain application of proposed methodology to extract new operator. Method: Divide into start to final step of hand gesture needed to extract as an operator through gesture task analysis. Then apply the original GOMS operator to each similar step of gesture and modify the operator for implementation stage based on existing Fitts' law research. Steps that are required to move are modified based on the Fitts' law developed in touch screen device. Finally, new operator can be derived from using these stages and a validation experiment, performed to verify the validity of new operator and methodology by comparing human performance. Results: The average movement times of the participants' performance and the operator which is extracted in case study are not different significantly. Also the average of movement times of each type of view study is not different significantly. Conclusion: In conclusion, the result of the proposed methodology for extracting new operator is similar to the result of the experiment with their participants. Furthermore the GOMS model included the operator by the proposed methodology in this research could be applied successfully to predict the user's performance. Application: Using this methodology could be applied to develop new finger gesture in the touch screen. Also this proposed methodology could be applied to evaluate the usability of certain system rapidly including the new finger gesture performance.

• The Journal of the Korea Contents Association
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• v.11 no.6
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• pp.350-359
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• 2011

The purpose of this study is to derive HRD programs for the government's priorities and HRD policy direction in the field of green technology to create green jobs. AHP methodology was employed by looking into "green job creation and HRD programs" announced by government. The empirical results showed that the most important one among 37 HRD programs was green education and research capacity building in engineering college and graduate school. And fostering green social enterprise, green education and research through university-research collaboration, green workers transition training, strategic partnership for green job are presented in order in terms of the importance. It suggested green creativity(0.384), green Industry growth (0.277), s정ustainable development (0.125), green technology spill-over effect (0.089), a global collaboration (0.084 ), and green cultural diffusion (0.042) as a green technology and HRD policy direction.

• Nuclear Engineering and Technology
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• v.53 no.3
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• pp.967-973
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• 2021

In 2011, an earthquake and subsequent tsunami hit the Fukushima Daiichi Nuclear Power Plant, causing simultaneous accidents in several reactors. This accident shows us that if there are several reactors on site, the seismic risk to multiple units is important to consider, in addition to that to single units in isolation. When a seismic event occurs, a seismic-failure correlation exists between the nuclear power plant's structures, systems, and components (SSCs) due to their seismic-response and seismic-capacity correlations. Therefore, it is necessary to evaluate the multi-unit seismic risk by considering the SSCs' seismic-failure-correlation effect. In this study, a methodology is proposed to obtain the seismic-response-correlation coefficient between SSCs to calculate the risk to multi-unit facilities. This coefficient is calculated from a probabilistic multi-unit seismic-response analysis. The seismic-response and seismic-failure-correlation coefficients of the emergency diesel generators installed within the units are successfully derived via the proposed method. In addition, the distribution of the seismic-response-correlation coefficient was observed as a function of the distance between SSCs of various dynamic characteristics. It is demonstrated that the proposed methodology can reasonably derive the seismic-response-correlation coefficient between SSCs, which is the input data for multi-unit seismic probabilistic safety assessment.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.39 no.3
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• pp.156-169
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• 2016

The objective of this study is to investigate patent trends of Daegu city which tries to introduce environment friendly energy and to develop new technology or new industry sprung from technology convergence on smart decentralized energy technology and other technologies. After applying network analysis to corresponding groups of technology or industry convergence, strategy for future energy convergence industry is provided. Patent data applied in Daegu city area are used to obtain research goal. The technology which contains several IPC codes (IPC Co-occurrence) is considered as a convergence technology. Path finder network analysis is used for visualizing and grouping by using IPC codes. The analysis results categorized 13 groups in energy convergence industry and reclassified them into 3 cluster groups (Smart Energy Product Production Technology Group, Smart Energy Convergence Supply Technology Group, Smart Energy Indirect Application Technology Group) considering the technical characteristics and policy direction. Also, energy industry has evolved rapidly by technological convergence with other industries. Especially, it has been converged with IT industry, and there is a trend that energy industry will be converged with service industry and manufacturing industry such as textile, automobile parts, mechanics, and logistics by employing infrastructure as well as network. Based on the research results on core patent technology, convergence technology and inter-industry analysis, the direction of core technology research and development as well as evolution on decentralized energy industry is identified. By using research design and methodology in this study, the trend of convergence technology is investigated based on objective data (patent data). Above all, we can easily confirm the core technology in the local industry by analyzing the industrial competitiveness in the macro level. Based on this, we can identify convergence industry and technology by performing the technological convergence analysis in the micro level.

• Nuclear Engineering and Technology
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• v.54 no.4
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• pp.1394-1405
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• 2022

The importance of ensuring the inherent safety and security has been more emphasized in recent years to demonstrate the integrity of nuclear facilities under external human-induced events (e.g. aircraft crashes). This work suggests a simulation methodology to effectively evaluate the impact of a commercial aircraft engine onto a dry storage facility. A full-scale engine model was developed and verified by Riera force-time history analysis. A reinforced concrete (RC) structure of a dry storage facility was also developed and material behavior of concrete was incorporated using three constitutive models namely: Continuous Surface Cap, Winfrith, and Karagozian & Case for comparison. Strain-based erosion limits for concrete were suitably defined and the local responses were then compared and analyzed with empirical formulas according to variations in impact velocity. The proposed methodology reasonably predicted such local damage modes of RC structure from the engine missile, and the analysis results agreed well with the calculations of empirical formulas. This research is expected to be helpful in reviewing the dry storage facility design and in the probabilistic risk assessment considering diverse impact scenarios.

• Nuclear Engineering and Technology
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• v.53 no.10
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• pp.3379-3397
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• 2021

In this study, a multi-physics modeling method was developed to analyze a nuclear fuel rod's thermo-mechanical behavior especially for high temperature anisotropic creep deformation during ballooning and burst occurring in Loss of Coolant Accident (LOCA). Based on transient heat transfer and nonlinear mechanical analysis, the present work newly incorporated the nuclear fuel rod's special characteristics which include gap heat transfer, temperature and burnup dependent material properties, and especially for high temperature creep with material anisotropy. The proposed method was tested through various benchmark analyses and showed good agreements with analytical solutions. From the validation study with a cladding burst experiment which postulates the LOCA scenario, it was shown that the present development could predict the ballooning and burst behaviors accurately and showed the capability to predict anisotropic creep behavior during the LOCA. Moreover, in order to verify the anisotropic creep methodology proposed in this study, the comparison between modeling and experiment was made with isotropic material assumption. It was found that the present methodology with anisotropic creep could predict ballooning and burst more accurately and showed more realistic behavior of the cladding.

• International Journal of Highway Engineering
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• v.17 no.2
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• pp.135-141
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• 2015

PURPOSES : While driving, drivers are usually limited in communicating with others except for using the horn. Excessive use of the horn may cause noise pollution, quarrels between drivers and pedestrians, damage, etc. This study developed a methodology for environmental adaptation and improvements of vehicle horns. METHODS: In this study, we performed a literature review of previous studies and related technologies regarding the overuse and damage of the horn. The proposed methodology employed the paired comparison method, as well as the semantic differential method. These methods can consider various vehicle horns, such as the Sport Utility Vehicle(SUV) Horn, Van Horn, and Buzzer. In addition, we conducted a factor analysis in order to provide a direction for improvement of future horns. This research provides a means of complimenting existing intellectual property related to vehicle horns. RESULTS: As a result, the most preferred of the selected horns were the Buzzer at 86.7%. In addition, based on the factor analysis, the horns could be classified into pleasantness and comfort factors. The results indicate a positive reaction for various vehicle horns. The horn type and size of the process control have been properly developed considering the position of the vehicle and the surrounding noise measurements. CONCLUSIONS : Based on the proposed methodology, public and private sectors can use fundamental data for reasonable traffic-noise control policies.