• Journal of Technology Innovation
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• v.27 no.3
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• pp.1-26
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• 2019

The Korean economy has undergone growth based on manufacturing end products. The Korean government aims to advance industry by strengthening the materials and components industry, which is attracting more attention in terms of maintaining the competitiveness of existing key industries, and fostering new industries required in the era of the Fourth Industrial Revolution. Despite this importance, there is insufficient related research on the efficient R&D of the materials and components industry. This study analyzed the R&D efficiency. In addition, exploratory research was conducted on the impact of corporate size and type of cooperation on R&D efficiency. Output variables were set to reflect economic performance and the empirical analysis revealed that overall R&D efficiency is low. Small firms were found to perform better than large firms in terms of firm-size, and the efficiency of business-university-research cooperation is worse than other types of cooperation. This study is exploratory research considering the materials and components industry, and the results provide implications for research institutions and regarding types of cooperation. This is expected to help develop polices for qualitative growth and R&D strategies for investment and allocation.

• Journal of Animal Science and Technology
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• v.51 no.2
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• pp.123-128
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• 2009

Recently, the $2^{nd}$ generation genome map of the Korean cattle (Hanwoo) has been constructed by comparison of the nucleotide sequence of the Korean cattle BAC clones with whole genome sequence of the bovine data-base (B_tau 2.1 build). The objective of this study was to update the $2^{nd}$ generation genome map of the Korean cattle using the similar approach. The nucleotide sequence of the Korean cattle BAC clones utilized in the construction of the $2^{nd}$ generation map was compared with the newly released bovine data-base (B_tau 3.1 build) to generate the $3^{rd}$ generation map. While, 5,105 BAC clones were localized on bovine chromosome in the $2^{nd}$ generation map, a total of 9,595 BAC clones, which spans about 37.27% of the bovine chromosome after eliminating the overlapping sequence among the clones, have been mapped on the bovine chromosome in the $3^{rd}$ generation map. Further analysis of the nucleotide sequence of the BAC clones will allow us to develop map and facilitate to pinpoint the genes that are important for the improvement of the performance in this cattle breed.

• Journal of the Earthquake Engineering Society of Korea
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• v.14 no.6
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• pp.1-9
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• 2010

Most of shear wall structures require openings in shear walls and thus shear walls are linked by floor slabs or coupling beams resulting in the coupled shear wall structures. When these structures are subjected to seismic excitations, excessive shear forces are induced in coupling beams. Accordingly, brittle failure of coupling beams may occur or shear walls may yield first. To avoid this problem, damping devices can be installed in coupling beams. It can increase the vibration control effect and improve the seismic resistance performance of the coupled shear wall structure by avoiding stress concentration and the brittle failure of coupling beams. Based on this background research, an LRB (lead rubber bearing) was introduced in the middle of the coupling beam in this study and the authors investigated the seismic response control effect and stress distribution of the proposed system. To this end, a modeling technique that can effectively predict the structural behavior of coupled shear wall structures has been proposed. With this proposed technique, time history analyses of the example coupled shear wall structure subjected to seismic excitation were performed and the vibration control effects of the seismic responses were investigated.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.5 s.347
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• pp.54-63
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• 2006

This work proposes a 14b 100MS/s 0.18um CMOS ADC with optimized resolution, conversion speed, die area, and power dissipation to obtain the performance required in the fourth-generation mobile communication systems. The 3-stage pipeline ADC, whose optimized architecture is analyzed and verified with behavioral model simulations, employs a wide-band low-noise SHA to achieve a 14b level ENOB at the Nyquist input frequency, 3-D fully symmetric layout techniques to minimize capacitor mismatch in two MDACs, and a back-end 6b flash ADC based on open-loop offset sampling and interpolation to obtain 6b accuracy and small chip area at 100MS/s. The prototype ADC implemented in a 0.18um CMOS process shows the measured DNL and INL of maximum 1.03LSB and 5.47LSB, respectively. The ADC demonstrates a maximum SNDR and SFDR of 59dB and 72dB, respectively, and a power consumption of 145mW at 100MS/s and 1.8V. The occupied active die area is $3.4mm^2$.

• Journal of The Korean Association For Science Education
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• v.30 no.6
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• pp.836-849
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• 2010

The purpose of this study is to analyze changes of competency observed in teaching of pre-service science teachers through the teaching evaluation and reflective journal writings on science class during the period of student-teaching at high school. To do this, we videotaped all the science classes of six pre-service teachers participating in this study, evaluated their class teachings, and collected moving video clips recorded in their classes, reflective journals, interviews, instructional materials, and teaching evaluation they have provided. From the "Standards for teaching evaluation of science instruction" developed by Korea Education Curriculum and Assessment, sixteen evaluation elements were selected and used for the analysis. According to our results, all preservice teachers show improvement of teaching performance in most of the class evaluation elements as the number of science classes increases. They presented the lowest improvement in the 'to design meaningful learning program,' which was one of the sixteen elements. However, there are substantial individual differences in the pre-service teachers' teaching competence on each evaluation element. Although they thought that 'understanding of scientific concepts' is the most important part of a science class in the beginning of student-teaching training, they showed changes in recognition that 'interaction and respect' and 'managing student behaviors' are also important in the end. They have recognized that writing a reflective journal, based on the video clips recorded in class and teaching evaluation, helps improve their teaching competency. In addition, improvement in teaching competency has influence upon career-orientation towards the school teacher in the future.

• The Korean Journal of Financial Management
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• v.27 no.1
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• pp.121-156
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• 2010

Back-door-listing can be viewed both as M&A and an alternative to IPO. If IPO is an access to the capital market through regulations, back-door-listing would be the way of entering the market through trading. Back-door-listing can be a better choice considering the common wisdom that regulations hinder the functioning of free market system. One would, however, prefer IPO, for the informational asymmetry isless severe in case of IPO. This paper examines if IPO is superior to back-door-listing as to the informational efficiency. The excess buy-and-hold returns of the Kosdaq back-door-listing firms are estimated over the three-year-period since the event. They are compared against the excess buy-and-hold returns of the Kosdaq IPO firms over the same period of time. The results confirm this paper's prediction that IPO should be more information-efficient. Both IPO and back-door-listing firms start with high short-term excess returns and end up with long-term under-performance. However, back-door-listing firms show more significantly damaging long-term results. Furthermore, back-door-listing firms record poorer accounting results over the research period. These results imply that there exists fad at the time of both events and, in case of back-door-listing, this fad is reinforced by the possibility of window dressing.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.289-294
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• 2007

It has been 10 years Since December 1996 when CM method was institutionalized by Construction Industry Fundamental law. Even though construction market has been in stagnant of business activities till now, CM in Korea started to be activated by the introduction of CM method i.n public construction. In the end of 2005, the number of CM order's contract is 6.7 times , an amount of CM order's money is 9.2 times more than operation plan of CM system announced in 2001. Therefore, CM market has been dramatically growing. However, it is judged that the shortage of faith in CM project and necessity of CM method are not recognized and study on a owner who affects successful settlement of CM has not been performed. When considering those points, in introduction and practical use of CM, CM is suggested to the field which is necessary for a client through the task performance level research and analysis of a owner who act a important role to activate Construction Management. As result of studying pre-existing papers to i.nvestigate of owner's capability level, the task function of a client is classified into 10 types and a public opinion poll was performed based on the 10 types of function.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.10
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• pp.883-891
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• 2016

In this paper, we propose an asymmetric dipole antenna utilizing the metal case as a ground radiator for a pen-type wireless presenter which operates in the ISM frequency band(2.4~2.48 GHz). A normal mode helix mounted on the top end of the long metallic cylinder case which acts as the ground plane takes the form of the asymmetric dipole structure in the proposed antenna. The metallic cylinder case which performs as a radiating element increases the inherent narrow bandwidth and low gain of the helix. The effects of the hand contacts with the metal case on the antenna performance are measured and analyzed with a specially designed human phantom. Experimental results show that the -10 dB return loss bandwidth of the proposed antenna in free space(no hand contact) is 200 MHz that ranges from 2.3 to 2.5 GHz and the maximum gain is measured to be 5 dBi. Under the normal operating condition where the metal case is contacted with a human hand, the bandwidth is 480 MHz from 2.24 to 2.72 GHz. The maximum gain is 2 dBi, lowered by 3 dB due to the hand contact.

• ALGAE
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• v.32 no.1
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• pp.57-66
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• 2017

The red alga Gracilaria vermiculophylla, a species native to the waters of Korea and Japan, has invaded marine coastal areas of Europe and the Americas, thriving in conditions that differ from those of its native habitat. In recent years, G. vermiculophylla has been discovered in the Long Island Sound (LIS) estuary growing alongside the native congener Gracilaria tikvahiae. The goal of this study was to determine whether the two strains of G. vermiculophylla from different regions of the world have evolved genetic differences (i.e., ecotypic differentiation) or if the physiological performance of the strains simply reflects phenotypic plasticity. Two strains of G. vermiculophylla (isolated in Korea and LIS) and a strain of the LIS native G. tikvahiae were grown for four weeks under temperatures ranging from 20 to $34^{\circ}C$ using a temperature gradient table (all other environmental conditions were kept constant). At the end of each week, wet weight of each sample was recorded, and thalli were reduced to the original stocking density of $1gL^{-1}$ (excess biomass was preserved for tissue carbon and nitrogen analysis). Generally, the growth rates of Korean G. vermiculophylla > LIS G. vermiculophylla > G. tikvahiae. After one week of growth G. tikvahiae grew 9.1, 12.0, 9.4, and 0.2% $d^{-1}$, at temperatures of 20, 24, 29, and $34^{\circ}C$, respectively, while G. vermiculophylla (LIS) grew 6.6, 6.2, 5.7, and 3.6% $d^{-1}$. G. vermiculophylla (Korea) grew 15.4, 22.9, 23.2, and 10.1% $d^{-1}$, much higher than the two strains currently inhabiting the LIS. On average, the LIS G. vermiculophylla strain contained 4-5% DW N, while the Korean strain and G. tikvahiae had more modest levels of 2-3% N DW. However, tissue N content declined as temperature increased in LIS and Korean G. vermiculophylla. The non-native haplotype may have evolved genetic differences resulting in lower growth capacity while concentrating significantly more nitrogen, giving the non-native a competitive advantage.

• The Journal of the Korea Contents Association
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• v.21 no.12
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• pp.140-154
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• 2021

This study examines the structural relationship between parents' positive and negative parenting attitudes, life satisfaction, and academic helplessness. To this end, 2,595 middle school students (1,405 boys and 1,185 girls) were used among the KCYPS 2018 panel materials. The model was validated using a structural equation model, and the verification of the mediated effects of life satisfaction was significant with bootstraps. The results of the study are as follows. First, the positive and negative parenting attitudes of parents have a significant impact on life satisfaction. These results can be interpreted as having an impact on the lives of adolescent children, depending on their parenting attitudes. Second, the positive and negative parenting attitudes of parents have a significant impact on academic helplessness. These results can be interpreted as having an effect on the academic performance of adolescent children depending on their parenting attitudes. Third, satisfaction in life has a significant adverse effect on academic helplessness. These results can be interpreted as having a positive impact on studies according to the satisfaction level of youth's life, and having a negative impact on studies if life satisfaction is high and life satisfaction is low. Fourth, the satisfaction of life is mediated between parents' positive and negative parenting attitudes and academic helplessness. Through this study, it is meaningful in that it allows parents to understand the process of life satisfaction affecting their academic helplessness according to their parenting attitudes.