• Proceedings of the Korean Nuclear Society Conference
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• 1999.05a
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• pp.21-21
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• 1999

• Journal of Technology Innovation
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• v.20 no.3
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• pp.1-28
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• 2012

This study conducted a qualitative analysis on the Korea's nuclear energy sector in 2030 through scenario-based strategic foresight method. Specifically, the relationships between environmental influencing factors of the future nuclear energy sector was examined from a multi-dimensional perspective on the basis of STEEP analysis and network analysis. In addition, scenario planning method was used with key uncertainty factors (KUF) to create three predictable strategic scenarios including optimistic, business as usual, and pessimistic. Common strategies that need to be urgently pursued as well as the maximum risk avoidance strategies for each scenario were also presented. This study further identified energy pricing, global economic trend, competitiveness in nuclear technology, and marketing capability as key uncertainty factors in the future nuclear energy industry sector. In order to furnish effective export strategy in the future nuclear energy sector, it was also suggested that government policy should adopt following measures as top priorities: securing nuclear safety technology, educating nuclear engineers, securing nuclear resources such as uranium, increasing nuclear capability and so on. The implications and limitations of this study were then discussed based on research findings.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.12 no.1
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• pp.111-122
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• 2001

This study analyzed the relationships among perceptions of uncertainty, environmental characteristics and strategy maker\`s actual decision such as resource allocation in different organizational subunits by focusing on the hotel general managers in two different countries Korea and Japan. The results show that managerial perceptions of the environment would vary across organizations within an industry but it was surprising to fad that managerial perceptions did not vary more substantially across countries. General managers in both countries perceived government regulator\`s actions to be the most uncertain environmental factor. Hotels in Japan were more geared toward external effectiveness than were hotels in Korea. The findings of this study also suggest that when the organization faces high environmental uncertainty, it places greater emphasis on extemally oriented functions such as market research and product development.

• International Journal of Naval Architecture and Ocean Engineering
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• v.10 no.4
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• pp.499-507
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• 2018

Autonomous Underwater Vehicle (AUV), which are becoming more and more important in ocean exploitation tasks, needs energy conservation urgently when sailing the complex mission path in long time cruise. As hull lines optimization design becomes the key factor, which closely related with resistance, in AUV preliminary design stage, uncertainty parameters need to be considered seriously. In this research, Myring axial symmetry revolution body with parameterized expression is assumed as AUV hull lines, and its travelling resistance is obtained via modified DATCOM formula. The problems of AUV hull lines design for the minimum travelling resistance with uncertain parameters are studied. Based on reliability-based optimization design technology, Design For Six Sigma (DFSS) for high quality level is conducted, and is proved more reliability for the actual environment disturbance.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.1
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• pp.20-33
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• 2015

Spectrum sensing is a key component of cognitive radio. The prediction of the primary user status in a low signal-to-noise ratio is an important factor in spectrum sensing. However, because of noise uncertainty, secondary users have difficulty distinguishing between the primary signal and an unauthorized signal when an unauthorized user exists in a cognitive radio network. To resolve the sensitivity to the noise uncertainty problem, we propose an entropy-based spectrum sensing scheme to detect the primary signal accurately in the presence of an unauthorized signal. The proposed spectrum sensing uses the conditional entropy between the primary signal and the unauthorized signal. The ability to detect the primary signal is thus robust against noise uncertainty, which leads to superior sensing performance in a low signal-to-noise ratio. Simulation results show that the proposed spectrum sensing scheme outperforms the conventional entropy-based spectrum sensing schemes in terms of the primary user detection probability.

• Journal of the Korean Society of Safety
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• v.24 no.2
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• pp.62-68
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• 2009

Life Cycle Cost(LCC) is adopted to decide the target of safety level in designing suspension bridges. The LCC are evaluated considering two types of uncertainty; aleatory and epistemic. The nine alternative designs of suspension bridge are simulated to decide the safety level which can minimize the LCC. The LCC is calculated through the probability of failure and safety index including the uncertainty. This method results in the useful tool deciding the optimum safety level with minimal LCC as the main design factor.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.55 no.3
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• pp.134-141
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• 2006

A potential transformer(PT) has ratio error and phase angle error. Precise measurement of the errors of PT can be achieved using high voltage capacitance bridge, high voltage capacitor and low voltage capacitor. The uncertainty for this method is evaluated and found to be $20{\times}10^{-6}$ in both ratio error and phase angle error. The values measured for PT using the method are well consistent with the those measured for same PT in NMIA(National Measurement Institute of Australia) within the corresponding uncertainty.

• Journal of the Korean Solar Energy Society
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• v.21 no.3
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• pp.25-32
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• 2001

The major purpose of this paper is to develop an uncertainty estimate for the calibration of thermopile instruments used to measure solar radiation parameters. We briefly describe the solar radiation parameters most often measured, instrumentation, reference standards, and calibration techniques. The bulk of the paper describes elemental sources of error and their magnitude. We then apply a standard error analysis methodology to combine these elemental error estimates into a statement of total uncertainty for the instrument calibration factor. Our results allow one to evaluate the accuracy of a radiometric measurement using thermopile instrumentation in the light of the application, such as engineering test evaluation or for validation of theoretical models.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10b
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• pp.656-661
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• 1998

This paper presents a method of statistical analysis and sensitivity analysis of creep and shrinkage effects in PSC box girder bridges. The statistical and sensitivity analyses are performed by using the numerical simulation of Latin Hypercube sampling. For each sample, the time-dependent structural analysis is performed to produce response data, which are then statistically analyzed. The probabilistic prediction of the confidence limits on long-term effects of creep and shrinkage is then expressed. Three measures are examined to quantify the sensitivity of the outputs to each of the input variables. These are rank correlation coefficient(RCC), partial rank correlation coefficient(PRCC) and standardized rank regression coefficient(SRRC) computed on the ranks of the observations. Probability band widens with time, which indicates an increase of prediction uncertainty with time. The creep model uncertainty factor and the relative humidity appear as the most dominant factors with regard to the model output uncertainty.

• Journal of Korea Society of Industrial Information Systems
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• v.27 no.1
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• pp.135-146
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• 2022

A safe working environment is an important and crucial factor in the operation of a firm, and is also essential for logistics companies in supply chain management. This study confirmed that the safety climate and safety prevention activities have a positive relationship with safety behavior from the perspective of domestic small and medium-sized logistics companies that continue their business relationships by signing contracts with large logistics companies. In addition, the moderating role of regulatory uncertainty and competition uncertainty in the previous positive relationship was empirically examined.