• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.04a
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• pp.79-82
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• 2003

With the wide application of fiber-reinforced composite material in aero-structures and mechanical parts, the design of composite joint have become a very important research area because they are often the weakest areas in composite structures. In this paper, the failure area index method to predict the failure load of the mechanically fastened composite joint was used and the prediction accuracies of the linear finite element analysis were compared with those of nonlinear finite element analysis.

• Journal of Korea Technology Innovation Society
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• v.8 no.2
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• pp.583-604
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• 2005

The future will see all industries become technology-driven in the competitive global market place. Firms with deep technological roots and innovation strategies have some advantages. In this situation widely used scoring approach is not enough to evaluate technology's relative competitiveness and to assign relative ranking category. Therefore, a more useful and comprehensive approach, which is called technology composite index, is needed to complement and enhance the existing scoring approach. In this research, factor analysis is applied to determine the common factors and to estimate associated weights. And technology composite index is used to measure the technology's relative strength and also to assign its ranking category instead of technology scoring.

• Physical Therapy Korea
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• v.13 no.1
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• pp.32-37
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• 2006

The purpose of this study was to investigate the effects of clinical characteristics of chronic stroke patients on physiological cost index (PCI) during walking. Fourteen stroke patients participated in this study. To investigate the clinical characteristics, Fugl-Meyer score (FMS), gait velocity (GV), muscle strength of the knee extensor, modified Ashworth scale (MAS) of ankle plantar flexor, devices, and gait patterns during walking were measured and analyzed. The results were as follows: Firstly, use of devices and high MAS of the ankle plantar flexor significantly increased PCI. Secondly, PCI was significantly correlated with the FMS and MAS of the ankle plantar flexor. In conclusion, inhibition of spasticity of the ankle plantar flexor is considered to reduce PCI during walking for chronic stroke patients.

• The Journal of Information Systems
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• v.28 no.3
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• pp.141-158
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• 2019

Purpose Artificial Intelligence (AI) is a core technology, leading the 4th industrial revolution. This study aims to diagnose the Korean's national competitiveness for AI technologies through patent analyses. Design/methodology/approach In this study, KIWEE and Derwent Innovation databases were used as data source of patents. we extracted 10,510 AI patents data with keywords and classified them into 15 subcategories of AI technology. We executed patent analyses for activity index, patent intensity index, technology strength, and patent family size and diagnosed Korea's national competitiveness in AI industry. Findings The results showed that Korea is less competitive than the United States and Japan in AI industry. However, patent amount has increased since 2010, which is encouraging result. This study has implication on the need for human and R&D investment in AI industry.

• Geomechanics and Engineering
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• v.29 no.3
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• pp.219-228
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• 2022

The most widely used parameter to represent rock abrasiveness is the Cerchar abrasivity index (CAI). The CAI value can be applied to predict wear in TBM cutters. It has been extensively demonstrated that the CAI is affected significantly by cementation degree, strength, and amount of abrasive minerals, i.e., the quartz content or equivalent quartz content in rocks. The relationship between the properties of rocks and the CAI is investigated in this study. A database comprising 223 observations that includes rock types, uniaxial compressive strengths, Brazilian tensile strengths, equivalent quartz contents, quartz contents, brittleness indices, and CAIs is constructed. A linear model is developed by selecting independent variables while considering multicollinearity after performing multiple regression analyses. Machine learning-based regression methods including support vector regression, regression tree regression, k-nearest neighbors regression, random forest regression, and artificial neural network regression are used in addition to multiple linear regression. The results of the random forest regression model show that it yields the best prediction performance.

• The Journal of Engineering Geology
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• v.1 no.1
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• pp.54-67
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• 1991

In geological media with anisotropic properties, the strength anisotropy in intact rock is the most important issue in engineering aspects. Point-ioad(P/L) strength test designed to estimate the uniaxial compressive strength(${\sigma}_c$) can be used to evaluate the anisotropic strength characteristics of rocks. The relationship between ${\sigma}_c$ and P/L strength indices(I$_s$), obtained from the banded gneisses distributed in the Cheongyang area, varies depend mainly on the dip angle($\beta$) of foliation. The axial P/L strength indicies(I$_{sa}$) decreases with the increment of $\beta$, whereas diametral P/L strength indices(I$_{sa}$) increase with it. However, the ${\sigma}_c$ decreases with the increments of $\beta$ below about 40$^{\circ}$, but it increases with the increments of $\beta$ over about 40$^{\circ}$ in general. The correlation between ${\sigma}_c$ and I$_s$ suggests that ${\sigma}_c$ is related to the Isa withing low angle($\beta$<40$^{\circ}$) and the I$_{sd}$ within high angle ($\beta$>40$^{\circ}$), respectively. The ratios of I$_s$ to ${\sigma}_c$ are obtained as 11 to 14 in the the gneisses in the study area. The ratio of 24, which is generally adopted value, cannot always be truthworth to the gneisses in the study area. The ratio for the dykes, however, show a good correlation as 21 to 24.5 and, the value of 24 can be used for a homogeneous and isotropic materials such as dykes.

• Phonetics and Speech Sciences
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• v.5 no.2
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• pp.11-22
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• 2013

The purpose of this study was to identify the relationship between the strength of the tongue/lip strength and speech production for dysarthric adults with cerebral palsy. The maximal tongue and lip strengths of 22 normal adults, 27 dysarthric adults (10 adults with mild dysarthria, 10 adults with moderate dysarthria, and 7 adults with severe dysarthria) were measured with Iowa Oral Performance Instrument (IOPI). The percentage of correct consonants (PCC) and speech intelligibility were calculated from the words and sentences spoken by the subjects. The results of the study are as follows: First, both the maximal tongue and the maximal lip strength differed significantly between the control group and the group with dysarthria. While the group with mild dysarthria did not show meaningful difference in maximal tongue and lip strengths from the control group, the group with moderate and severe dysarthria showed significantly weaker tongue and lip strength than the control group and the group with mild dysarthria. Second, the current study suggests the existence of a significant correlation between the maximal tongue and lip strength and the PCC and speech intelligibility within all subjects with dysarthria. These findings can serve as an effective foundation to diagnose dysarthria quickly and accurately. The results of this study also indicate that in addition to the maximal tongue strength, the maximal lip strength can prove to be an important index in predicting the speech intelligibility of dysarthric adults with cerebral palsy.

• Journal of Ocean Engineering and Technology
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• v.3 no.2
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• pp.645-645
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• 1989

• Journal of the Korean Chemical Society
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• v.54 no.6
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• pp.829-834
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• 2010

• Journal of the Korean Chemical Society
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• v.54 no.6
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• pp.835-840
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• 2010