• Journal of the Korea Concrete Institute
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• v.17 no.5 s.89
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• pp.709-716
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• 2005

The objective of this study is to develop a high ductile fiber reinforced mortar, ECC(Engineered Cementitious Composite) with using raw material commercially available in Korea. A single fiber pullout test and a wedge splitting test were employed to measure the bond properties in a matrix and the fracture toughness of mortar matrix respectively, which are used for designing mix proportion suitable for achieving strain-hardening behavior at a composite level. Test results showed that the properties tended to increase with decreasing water-cement ratio. A high ductile fiber reinforced mortar has been developed by employing micromechanics-based design procedure. Micromechanical analysis was initially peformed to properly select water-cement ratio, and then basic mixture proportion range was determined based on workability considerations, including desirable fiber dispersion without segregation. Subsequent direct tensile tests were performed on the composites with W/C's of 47.5% and 60% at 28 days that the fiber reinforced mortar exhibited high ductile uniaxial tension property, represented by a maximum strain capacity of 2.2%, which is around 100 times the strain capacity of normal concrete. Also, compressive tests were performed to examine high ductile fiber reinforced mortar under the compression. The test results showed that the measured value of compressive strength was from 26MPa to 34 MPa which comes under the strength of normal concrete at 28 days.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.2
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• pp.21-28
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• 2010

This paper reports an experimental result on optimizing dissimilarity-based classification(DBC) by simultaneously using a dynamic time warping(DTW) and a multiple fusion strategy(MFS). DBC is a way of defining classifiers among classes; they are not based on the feature measurements of individual samples, but rather on a suitable dissimilarity measure among the samples. In DTW, the dissimilarity is measured in two steps: first, we adjust the object samples by finding the best warping path with a correlation coefficient-based DTW technique. We then compute the dissimilarity distance between the adjusted objects with conventional measures. In MFS, fusion strategies are repeatedly used in generating dissimilarity matrices as well as in designing classifiers: we first combine the dissimilarity matrices obtained with the DTW technique to a new matrix. After training some base classifiers in the new matrix, we again combine the results of the base classifiers. Our experimental results for well-known benchmark databases demonstrate that the proposed mechanism achieves further improved results in terms of classification accuracy compared with the previous approaches. From this consideration, the method could also be applied to other high-dimensional tasks, such as multimedia information retrieval.

• Journal of Life Science
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• v.15 no.1 s.68
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• pp.80-86
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• 2005

To achieve the purpose of this study, forty-eight male Sprague-Dawley rats were assigned to control and three endurance exercise group. 36 rats were forced to exercise according to exercise intensity for 8 weeks and 12 rats were untrained for control group. Cardiac cytosol was extracted from cardiac tissue and cardiac mitochondria was purified from the cytosol. Purified mitochondria were separated into four fraction: inner membrane, outer membrane inter membrane space and matrix. The changes of cytosolic and mitochondrial LDH isozymes activity were measure. Relative activity $(\%)$ of cytosol for low and control group showed the following order of prevalence $AB_3>A_2B_2>B_4>A_3B>A_4$ for moderate and high group : $AB_3>B_4>A_2B_2>A_3B>A_4$. Outer membrane for low group showed $AB_3>B_4>A_2B_2$, for moderate group:$ B_4>AB_3>A_2B_2$, for high and control group: $B_4>A_3B$. Inter membrane space for low, moderate and high group showed $B_4>AB_3>A_2B_2>A_3B>A_4$, for control group: $B_4>A_3B>AB_3>A_2B_2>A_4$. Inner membrane for all group showed $B_4>AB_3>A_2B_2>A_3B>A_4$. Matrix for control, low, moderate and high group showed $B_4>AB_3>A_2B_2>A_3B>A_4$. These results suggest that long term exercise intensity effect on cardiac tissue cytosolic and mitochondrial activity and $A_4,\;A_3B,\;A_2B_2,\;AB_3\;and\;B_4$ isozymes were found entirely in mitochondrial fraction.

• Progress in Medical Physics
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• v.12 no.1
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• pp.9-17
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• 2001

The prior purpose of this study is to introduce a optical biopsy and evaluate whether the optical biopsy, real-time, non-invasive technique, is a reliable tool to assess response to radiotherapy Four healthy volunteers, and four patients with inflammatory conditions of the oral cavity participated on the study. was obtained from each person enrolled in the study. Using FastEEM(Ercited Emission Matrix) as a optical biopsy tool, normal and tumor spectra are taken from the normal and the tumor regions. And then second optical biopsy are taken from the tumor regions in 4 patients with time delay at 7days.. Using a diagnostic algorithm, made by Gillenwater based on spectra excited at 337nm The Optical Biopsy turned out to be more suited for tumor diagnostic resulting in significant difference fluorescence spectra. The fluorescence intensity of cancerous tissue showed a higher position. The second fluorescence intensity of optical biopsy of cancerous oral tissue has more smaller than the first result. I conclude that optical biopsy, which technique don't need to remove tissue sample from body, and is a real time , and non-invasive measurement is a reliable tool to access to radiotherapy because FastEEM can do measure the variation of the tissue composition chemical, biological, and morphological after radiotherapy. Based on the fluorescence spectrum are taken from the optical biopsy in normal and tumor spectra as well as tumor spectra after 7days.

• Journal of Technology Innovation
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• v.22 no.3
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• pp.225-260
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• 2014

In this paper, we present a literature review of the mechanisms and methodology for technology spillover, in order to provide a theoretical and practical foundation for estimating the technology spillover effect of public funded R&D programs. Our research consists of four parts. First, we investigate what technology spillover is and how it works. Second, we review the methodology used to empirically measure technology spillover, with a view to understanding the advantages and disadvantages of each method. Third, we identify the gap between the spillover phenomenon and its estimated results, caused by the limitations of the methodology, and discuss the challenges in measuring technology spillover. Finally, we present several considerations to improve the measurement of technology spillover in the context of public funded R&D programs. Our paper provides policy makers and researchers with basic knowledge about technology spillover and helps them suitably evaluate the results obtained from the literature review. In addition, it contributes towards improving the existing methodology by recognizing the gap between the spillover phenomenon and the methodology.

• Korean Journal of Environmental Agriculture
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• v.21 no.2
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• pp.90-95
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• 2002

A study was carried out to optimize the cleanup step using a solid-phase extraction (SPE) cartridge, $SupelClean^{TM}$ Florisil, for multiresidue analysis of 16 pesticides in cucumber matrix. Eluting efficiencies of two solvent systems including acetone/n-hexane and ethyl acetate/n-hexane mixtures were critically evaluated by recoveries of target anaytes from the SPE Florisil column. Based on the recovery as a measure of eluting efficiency, an acetone/n-hexane (20/80,v/v) mixture provided more than 80% recovery for 15 pesticides except bifenthrin. In case of ethyl acetate/n-hexane, 14 pesticides showed recoveries higher than 75% while those far alachlor and bifenthrin were less than 30%.

• Korean Journal of Optics and Photonics
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• v.25 no.1
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• pp.29-37
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• 2014

We have studied and demonstrated general, systematic error-correction methods for a dual rotating quarter-wave plate ellipsometer. To estimate and correct 5 systematic error sources (three offset angles and two unexpected retarder phase delays), we used 11 of the 25 Fourier components of the ellipsometry signal obtained in the absence of an optical sample. Using these 11 Fourier components, we can determine the errors from the 5 sources with nonlinear optimization methods. We found systematic errors ${\epsilon}_3$, ${\epsilon}_4$, ${\epsilon}_5$) are more sensitive to the inverted Mueller matrix than retarder phase delay errors (${\epsilon}_1$, ${\epsilon}_2$) because of their small condition numbers. To correct these systematic errors we have found that error of any variety must be less than 0.05 rad. Finally, we can use the magnitudes of these errors to correct the Mueller matrix of optical components. From our experimental ellipsometry signals, we can measure phase delay and the rotational angular position of its fast axis for a half-wave plate.

• Journal of the Korean Society for Railway
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• v.11 no.4
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• pp.357-363
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• 2008

This study investigates the durability of carbon/epoxy composites for use on train car bodies under a salt water spray environment. Salt water solution with 5% NaCl, similar to natural salt water, was used for the salt water environmental tests. The specimens were obtained from a composite panel consisting of an epoxy matrix reinforced with T700 carbon fabric. The specimens were exposed to the salt water environment for up to 12 months. Mechanical tests were performed to obtain tensile properties, flexural properties, and shear properties. Dynamic mechanical analysis was used to measure such thermal properties as storage modulus, loss modulus, and tan $\delta$. Also FT/IR tests were conducted to investigate changes in chemical structure with exposure. The results revealed that fiber-dominated mechanical properties were not affected much by exposure time, but matrix-dominated mechanical properties decreased with increasing exposure time. Storage modulus was not very sensitive to exposure time, but glass transition temperature was affected, slightly decreasing with increasing exposure time. Although the peak intensity of FT/IR curves was affected slightly by exposure time, the peak shape and peak location of FT/IR curves were not noticeably changed. Carbon/epoxy composites used for this study were relatively stable to the salt water environment.

• Journal of Korean society of Dental Hygiene
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• v.24 no.4
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• pp.301-309
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• 2024

Objectives: This study aimed to measure the awareness and needs for intellectual property (IP) education among university students majoring in health-related fields to inform the development of future IP education curricula. Methods: The study was conducted through an online survey from January 5 to 26, 2024, targeting students from the health-related departments (Department of Physical Therapy, Health Administration, Clinical Laboratory Science, and Dental Hygiene) at Dankook University located in Cheonan City, Chungcheongnam-do. Results: A total of 151 students participated in the survey. Among the respondents, 84.8% were women, and the largest groups of respondents were from the Health Administration and Dental Hygiene departments, each accounting for 32.5%. Only 13.9% of the respondents had taken courses related to IP, and 22.5% had related activity experience. The overall average importance score of IP education was 3.88 (±0.80), and the overall average need score was 3.78 (±0.80). An Importance-Performance Analysis (IPA) Matrix analysis revealed that 13 topics fell into the first quadrant (high importance, high need), one topic into the second quadrant (low importance, high need), 18 topics into the third quadrant (low importance, low need), and four topics into the fourth quadrant (high importance, low need). The educational topics identified as first quadrant include 'Securing patent rights', 'Requirements for patent registration', 'Effects and contents of patent rights', 'Patent infringement and remedies', and 'Effects and contents of copyrights'. Conclusions: Future IP education programs should develop innovative educational content and methods that consider both the importance and needs to increase students' interest and engagement.

• Proceedings of the Technology Innovation Conference
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• 1996.12a
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• pp.265-295
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• 1996

This paper investigates empirically the relationship between various business portfolio properties (particularly technological properties) and chaebol′s performance using data on the 50 largest chaebols in Korea. In addition to the traditional indexes to measure diversification such as entropy index we calculated inter-industry technological similarity using R&D expenditure data by industry and 1990 Input-output Table in Korea, and obtained chaebol-level technological relatedness and internal transaction proportion from chaebols′business profile, inter-industry technological similarity and 1990 input-output table. We applied factor analysis on 13 business portfolio property indexes and showed that they could be grouped into 3 dimensions, diversification scope, inter-business relatedness and degree of vertical integration. In this paper, using 50 largest chaebols′financial data (1989-1994), we analyzed empirically the effect of business portfolio properties on ROS (Return On Sales) which is conventional index for firm performance and on TFP(Total Factor Productivity) growth which is a pure measure of firm performance. To utilize the advantage of panel data, FEM(Fixed Effect Model) and REM(Random Effect Model) were used. The empirical result shows that the entropy index as a measurement of inter-business relatedness is not significant but technological relatedness index is significant. OLS estimates on pooled data were considerably different from FEM or REM estimates on panel data. By introducing interaction effect among the three variables for business portfolio properties, we obtained three findings. First, only VI (Vertical integration) has a significant positive correlation with ROS. Second, when using TFP growth as an dependent variable, both TR(Technological Relatedness) and f[ are significant and positively related to the deepened variable. Third, the interaction term between TR and VI is significant and negatively affects TFP growth, meaning that TR and VI are substitutes. These results suggest strategic directions on restructuring business portfolio. As VI is increased, chaebols will get more profit. A higher level of either TR or W will increase TFP growth rate. but increase in both TR and VI will have a negative effect on TFP growth. To summarize, certain business portfolio properties such as VI and TR can be considered "resources" themselves since they can affect profit rate and productivity growth. VI and TR have a synergy effect of change in profit rate and productivity growth. VI increases ROS and productivity growth, while TR increases productivity growth representing a technological synergy effect.