• Earthquakes and Structures
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• v.20 no.1
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• pp.97-107
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• 2021

A comprehensive study on seismic performance of wood frame building in hilly regions is presented. Specifically, seismic fragility assessment of a typical wood frame building at various locations of the northeast region of India are demonstrated. A three-dimensional simplified model of the wood frame building is developed with due consideration to nonlinear behaviour of shear walls under lateral loads. In doing so, a trilinear model having improved capability to capture the force-deformation behaviour of shear walls including the strength degradation at higher deformations is proposed. The improved capability of the proposed model to capture the force-deformation behaviour of shear wall is validated by comparing with the existing experimental results. The structural demand values are obtained from nonlinear time history analysis (NLTHA) of the three-dimensional wood frame model considering the effect of uncertainty due to record to record variation of ground motions and structural parameters as well. The ground motion bins necessary for NLTHA are prepared based on the identified hazard level from probabilistic seismic hazard analysis of the considered locations. The maximum likelihood estimates of the lognormal fragility parameters are obtained from the observed failure cases and the seismic fragilities corresponding to different locations are estimated accordingly. The results of the numerical study show that the wood frame constructions commonly found in the region are likely to suffer minor cracking or damage in the shear walls under the earthquake occurrence corresponding to the estimated seismic hazard level; however, poses negligible risk against complete collapse of such structures.

• Journal of the Korean Society of Industry Convergence
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• v.27 no.3
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• pp.535-546
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• 2024

This research aims to develop a model to objectively and quantitatively measure the skill level of aircraft body assembly workers. Because aircraft body assembly is predominantly a manual process, skills management is a key factor of manufacturing competitiveness. Currently, skills management relies on the subjective judgment of supervisors, which lacks objectivity and reliability. As a remedy, this study proposed a systematic skill management model based on objective and quantitative evaluation criteria. By considering prior research, we developed an evaluation model that takes into account both expertise and versatility of a worker. The model selected five major tasks required for aircraft body assembly and established evaluation criteria considering the difficulty and maturity of each task. We then conducted a pilot evaluation with over 200 workers in four SMEs to validate the practicality and effectiveness of the model. Consequently, we identified and addressed the limitations of the existing evaluation method, subdivided the skill levels based on the performance capabilities of each task, and proposed a career growth path. The developed evaluation model offers critical data for executives and managers to determine work assignments, education, training, performance incentives, and wages. It is expected to enhance the attraction of new talent and systematize skills management in aviation manufacturing in the future.

• Clean Technology
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• v.21 no.3
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• pp.171-177
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• 2015

A life cycle assessment (LCA) methodology was employed to evaluate environmental impact of recycled polyol from polyurethane in an R&D stage and to suggest future direction for improvement of environmental performance of the recycling technology. The comparison result shows between recycled polyol in the developing stage and in the anticipated mass production with virgin polyol production that environmental impact of recycled polyol of the developing stage and the anticipated mass production level correspond to 93%, 60% of that of virgin polyol, respectively. The LCA result identifies improvement areas of reducing environmental impact in recycling polyols, that is, use of alkylene oxide and steam. In the future research, this must be taken into consideration for better performance of recycling technology.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.1
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• pp.111-119
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• 2015

The negative factors of fishery in environmental aspect of view are Greenhouse gas emission problems by high usage of fossil fuel, destruction of underwater ecosystem by bottom trawls, reduction of resources by fishing and damage of ecosystem diversity. Especially, the Greenhouse gas emission from fisheries is an important issue due to Canc$\acute{u}$n meeting, Mexico in 1992 and Kyoto protocol in 2005. However, the investigation on the GHG emissions from Korean fisheries did not much carry out. Therefore, the quantitative analysis of GHG emissions from Korean fishery industry is needed as a first step to find a relevant way to reduce GHG emissions from fisheries. The purpose of this research is to investigate which degree of GHG emitted from fishery. Here, we calculated the GHG emission from Korean bottom pair trawl fishery using the LCA (Life Cycle Assessment) method. The system boundary and input parameters for each process level are defined for LCA analysis. The fuel use coefficient of the fishery is also calculated. The GHG emissions from the representative fishes caught by bottom pair trawl will be dealt with. Furthermore, the GHG emissions for the edible weight of fishes are calculated with consideration to the different consuming areas and slaughtering process also. The results will be helpful to understand the circumstances of GHG emissions from Korean fisheries.

• Journal of Environmental Impact Assessment
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• v.8 no.4
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• pp.59-72
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• 1999

The purpose of the study is to propose the concrete and realistic alternative measures for $CO_2$ emission reduction on commercial sector. To achieve the purpose, this study adopted AIM/KOREA simulation model modified from AIM(Asia-Pacific Integrated Model) originally developed by Japan National Environmental Research Institute. The results of simulation demonstrate that the $CO_2$ emission from the commercial sector in 1995 was estimated 864 million TC(tons of carbon); however, according to the base scenario, $CO_2$ emission in 2020 is expected to be increased to 1,872 million TC, which is 2.17 times greater than that in 1995. In order to mitigate the ever-increasing $CO_2$ emission, the results of AIM/KOREA simulations under various scenarios showed that the 30-thousand-won carbon tax scenario does not successfully motivate the selection of advanced technology; however, with the 300-thousand-won carbon tax, a substantial amount of $CO_2$ emission reduction by 1.69 million TC from the BaU((Business-as-Usual)scenario is expected to be achieved by year 2020. Such substantial reduction of $CO_2$ emission under the 300-thoudsand-won carbon tax scenario is due to the introduction of advanced technology, such as use of condensing boilers, forced by heavier carbon tax. Under the scenario that presumes the maximum introduction of gas-burning industrial appliances, an 2.66 million TC of $CO_2$ reduction was expected. The results of this study suggest that the $CO_2$ emission reduction measures can be interpreted in many different views. However, if people and industries are fully aware of the economic benefit of energy saving, a certain level of $CO_2$ reduction by a successful introduction of advanced energy saving technology appears to be achieved without carbon tax or subsidies.

• Journal of Korea Technology Innovation Society
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• v.16 no.1
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• pp.20-40
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• 2013

A project of developing marine environmental risk assesment and management technology was proposed to improve the level of marine environmental management research. This paper attempts to measure the non-market benefits of the project. To this end, the dichotomous choice contingent valuation method is used. In particular, recently proposed one and one-half bounded model is applied. The model can reduce the potential for response bias comparing to the double bounded model while maintaining much of its efficiency. Moreover, in order to deal with zero WTP observations, a spike model is adjusted for our data. A survey of randomly selected 600 households was implemented and the respondents were asked in person-to-person interviews about how they would be willing to pay for implementing the project. Respondents overall accepted the contingent market and were willing to contribute a significant amount (2,663 won), on average, per household per year. The aggregate value of the project in the nation amounts to approximately 46.3 billion won per year. The figure 2.16 of cost-benefit ratio shows that economic validity of this technical development.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.3
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• pp.279-287
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• 2016

Korea Radioactive Waste Agency (KORAD) began to operate the low and intermediate level radioactive waste disposal facility in Gyeongju and to transport the radioactive waste containing radioactive isotopes from Daejeon to the disposal facility for the first time at 2015. For this radioactive waste transportation, in this study, radiological impact assessment is carried out for workers and public. The dose rate to workers and public during the transportation is estimated with consideration of the transportation scenarios and is compared with the Korean regulatory limit. The sensitivity analysis is carried out by considering both the variation of release ratios of the radioactive isotopes from the waste and the variation of the distances between the radioactive waste drum and worker during loading and unloading of radioactive waste. As for all the transportation scenarios, radiological impacts for workers and public have met the regulatory limits.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.1
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• pp.22-32
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• 2019

On offshore platforms, oil and gas leaks are apt to be the initial events of major accidents that may result in significant loss of life and property damage. To prevent accidents induced by leakage, it is vital to perform a case-specific and accurate risk assessment. This paper presents an integrated method of Ddynamic Qquantitative Rrisk Aassessment (DQRA)-using the Decision Making Trial and Evaluation Laboratory (DEMATEL)-Bayesian Network (BN)-for evaluation of the system vulnerabilities and prediction of the occurrence probabilities of accidents induced by leakage. In the method, three-level indicators are established to identify factors, events, and subsystems that may lead to leakage, fire, and explosion. The critical indicators that directly influence the evolution of risk are identified using DEMATEL. Then, a sequential model is developed to describe the escalation of initial events using an Event Tree (ET), which is converted into a BN to calculate the posterior probabilities of indicators. Using the newly introduced accident precursor data, the failure probabilities of safety barriers and basic factors, and the occurrence probabilities of different consequences can be updated using the BN. The proposed method overcomes the limitations of traditional methods that cannot effectively utilize the operational data of platforms. This work shows trends of accident risks over time and provides useful information for risk control of floating marine platforms.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.55 no.1
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• pp.50-61
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• 2019

The concern on the greenhouse gas emissions is increasing globally. Especially, the greenhouse gas emission from fisheries is an important issue from the Paris Climate Change Accord in 2015. Furthermore, the Korean government has a plan to reduce the GHG emissions as 4.8% compared to the BAU in fisheries until 2020. However, the investigation on the GHG emissions from Korean fisheries rarely carried out consistently. Therefore, the quantitative analysis of GHG emissions from Korean fishery industry is necessary as a first step to find a relevant way to reduce GHG emissions from fisheries. The purpose of this research is to investigate which degree of GHG emitted from the major offshore fisheries such as offshore gillnet fishery, offshore longline fishery, offshore jigging fishery and anchovy drag net fishery. Here, we calculated the GHG emissions from the fisheries using the Life Cycle Assessment method. The system boundary and input parameters for each process level are defined for the LCA analysis. The fuel use coefficients of the fisheries are also calculated according to the fuel type. The GHG emissions from sea activities by the fisheries will be dealt with. Furthermore, the GHG emissions for the unit weight of fishes are calculated with consideration to the different consuming areas as well. The results will be helpful to understand the circumstances of GHG emissions from Korean fisheries.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.26 no.4
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• pp.985-994
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• 2016

Since the inauguration of Defense Acquisition Program Administration(DAPA) in 2006, the national defense core technology research & development business has not only pertained to the weapons systems development but also to the improvement of the national science & technology capability via the acquisition of cutting-edge technologies. Furthermore, it has been closely related to the promotion of the defense industry and the mutual improvements of defense and civil technologies. The cyber warfare weapon system, a newly added national defense weapon system field since 2015, has become a promising weapon system branch for improving the national defense power as well as the national defense industry as shown in the case of Israel. By utilizing the existing result of the national defense core technology level, in order to establish the direction of technology planning of the cyber warfare weapon system, this paper analyzes the technology level and features of the cyber warfare weapon system in various aspects via comparisons with other weapons systems. The result of these analyses shows that the cyber warfare weapon system possesses a relatively high technology level due to the technology accumulation in the civilian sector while the relatively slow inclusion to the national weapons systems and the lack of the correspondence case regarding aggressive cyber responses in the defense sector yields a relatively low national rank. However, the technological gap between South Korea and the most advanced country in the field of cyber warfare technology is analyzed to be among the lowest, which indicates that with efficient and effective pursuits in terms of pthe weapons systems acquisitions as well as the core technologies research & development business, an outstanding cyber warfare capacity can be obtained in a short time.