• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.2
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• pp.91-94
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• 2003

Rhizotron technique was used to determine the zone of active root growth in contrasting field situations. The distribution of roots with depth showed most root in the 15∼30 cm layer with fewer in the 0∼15 cm and below 30 cm layer at Lincoln Farm, while root density increased with depth at Winchmore. At Mt Johm (Lake Tekapo) roots were more distributed near soil surface. Root density was increased with fertilizer and irrigation at Mt John. Root number showed the same trends as root length at all lesions. Tube method was good for comparative purposes, and for long-term root growth studies at the same place.

• Journal of Microbiology and Biotechnology
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• v.25 no.7
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• pp.1114-1118
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• 2015

Microbial fuel cells (MFCs) have gathered attention as a novel bioenergy technology to simultaneously treat wastewater with less sludge production than the conventional activated sludge system. In two different operations of the MFC and aerobic process, microbial growth was determined by the protein assay method and their biomass yields using real wastewater were compared. The biomass yield on the anode electrode of the MFC was 0.02 g-COD-cell/gCOD-substrate and the anolyte planktonic biomass was 0.14 g-COD-cell/g-COD-substrate. An MFC without anode electrode resulted in the biomass yield of 0.07 ± 0.03 g-COD-cell/g-CODsubstrate, suggesting that oxygen diffusion from the cathode possibly supported the microbial growth. In a comparative test, the biomass yield under aerobic environment was 0.46 ± 0.07 g-COD-cell/g-COD-substrate, which was about 3 times higher than the total biomass value in the MFC operation.

• Child Health Nursing Research
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• v.15 no.4
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• pp.335-342
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• 2009

Purpose: This study, using a pre-post test design of non-equivalence comparative group, was done to determine effects of Kangaroo care (KC) on growth in premature infants and on maternal attachment (MA). Methods: Fifty-three premature infants were assigned to the KC (24) or control group (CG) (29). Data were collected from July 2007 to June 2008. KC was given for 60 min at a time, Monday, Wednesday, and Friday for 10 times. Weight, height, and head circumference (HC) of premature infants were checked before the program started. Following the initial measurement, the program was given and measurements were taken again at the end of the program. For measurement of attachment between mother and infant, data collection was done using structured self-reported questionnaires. Results: KC group had a higher weight (t=2.565, p=.013), height (t=2.182, p=.034) and HC (t=2.468, p=.017) than the CG. Compared to the CG, the KC had significantly higher scores in MA (t=2.026, p=.048). Conclusion: The results of this study suggest that the practice of KC in the nursing environment might actively promote attachment between mother and infant as well as acceleration of growth for premature infants as one of the most efficient nursing intervention.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.4
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• pp.563-565
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• 2020

Turbot Scophthalmus maximus can be cultured at a higher density and has a faster growth rate than olive flounder Paralichthys olivaceus, making it an attractive alternative for flounder farmers in Korea. As it is a relatively new species to Korean farming environments, there is no general farming protocol, which takes multiple generations to develop, for turbot in Korea. Nevertheless, we applied breeding technology to develop a stock, which we considered first-generation turbot. Then we compared its growth rate (an important economic trait) to different populations (the original stock of Korean turbot, French turbot, and Chinese turbot). The four different populations were grown in similar culture conditions. First-generation Korean turbots grew about 28% faster than all others. We will continue to select for important traits such as color, disease resistance, and heat tolerance in this turbot broodstock; we believe that with the appropriate selection process, Korean turbot should become competitive in the markets, and will become a major farming species in the Korean aquaculture industry.

• Molecules and Cells
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• v.21 no.1
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• pp.82-88
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• 2006

The global pattern of growth-dependent gene expression in Streptococcus pneumoniae strains was evaluated using a high-density DNA microarray. Total RNAs obtained from an avirulent S. pneumoniae strain R6 and a virulent strain AMC96-6 were used to compare the expression patterns at seven time points (2.5, 3.5, 4.5, 5.5, 6.0, 6.5, and 8.0 h). The expression profile of strain R6 changed between log and stationary growth (the Log-Stat switch). There were clear differences between the growth-dependent gene expression profiles of the virulent and avirulent pneumococcal strains in 367 of 1,112 genes. Transcripts of genes associated with bacterial competence and capsular polysaccharide formation, as well as clpP and cbpA, were higher in the virulent strain. Our data suggest that late log or early stationary phase may be the most virulent phase of S. pneumoniae.

• The Korean Journal of Pesticide Science
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• v.7 no.2
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• pp.75-82
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• 2003

We discuss that the growth inhibition activities against root and shoot of rice plant (Oryza sativa L.) and barnyard grass (Echinochloa crus-galli) by N-phenyl-3,4,5,6-tetrahydrophthalimide (A) and N-phenyl-3,4-dimethylmaleimide (B) derivatives with changing substituents can be explained and predicted using comparative molecular field analyses (CoMPA) method. And the results show that the cross-validation value, $q^2$ at three components and Pearson correlation coefficient, $r^2$ were rice plant: shoot; $r^2=0.987$, $q^2=0.387$ & root; $r^2=0.923$, $q^2=0.307$ and barnyard grass: shoot; $r^2=0.902$, $q^2=0.535$ & root; $r^2=0.900$, $q^2=0.450$, respectively. In addition, The activities of unknown compounds were predicted by CoMFA method. From the contour map of (A) derivatives, the selective factors to remove barnyard grass takes positive charge on the benzylic carbon atom (C27), negative charged carbon atom (C29) of meta position and steric bulky groups on the cyclic imino ring (C7-C8).

• Journal of Korea Port Economic Association
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• v.34 no.2
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• pp.1-16
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• 2018

Maritime industry is recognized as a new value-adding and growth engine industry. It provides high value by creating clusters centering on ports. Advanced international ports are also clashing ahead to create clusters, boost profits, and strengthen competitiveness. The Korean government enacted policies for the establishment and upbringing of maritime industrial clusters in 2015. It is very important to understand which maritime industry has a comparative advantage in each region and to establish an integration strategy through maritime industrial clusters. This study analyzes the structure of the maritime industry in the Chungnam province, which is expected to deal with raw materials(mainly oil products), container throughput, and opening of ferry route with China's port. The study analyzed the existing literature on the maritime industry and classified the industry into 5 major categories, 21 sub-categories, and 84 sub-categories in shipping and logistics, shipbuilding, fishery, marine tourism industry, and other industries. Based on the reclassified maritime industry, the structure of the maritime industry in the Chungnam province was analyzed by using location quotient(LQ) and Shift-Share analysis. The study found that the fisheries industry showed the highest value(1.718) in the analysis of LQ, followed by the marine tourism industry(1.092), shipbuilding industry(0.823) and shipping and logistics industry(0.789). The total effect of the maritime industry in Chungnam province was 36,315 and the net growth effect, excluding the national growth effect, was estimated to be 21,321. Based on these results, we classify the maritime industry in the Chungnam province as comparative advantage and comparative disadvantage. The results of this study can be used as basic data for formulating strategies for the construction of the maritime industry cluster in the Chungnam province in the future.

• Journal of Korea Trade
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• v.27 no.2
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• pp.61-76
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• 2023

Purpose - The digital service trade has become an important driver of the global service trade. The main purpose of this study is to explore the influencing factors of digital service exports from China and Korea to RCEP sample countries respectively, and to comprehensively study the export potential of China and Korea to RCEP countries, so as to provide theoretical guidance and a decision-making reference to promote digital service trade exports and digital economy development in China and Korea. Design/methodology - First, the stochastic frontier gravity model was improved by introducing nonefficiency factors affecting digital services trade, extending the gravity model of traditional services trade exports to digital services trade exports. Secondly, the panel data of China and Korea for the eight sample countries of RCEP from 2011 to 2021 were adopted for the empirical analysis of digital service export potential by a stochastic frontier model. Findings - China's economic growth plays a role in increasing China's digital service trade exports, while Korea's economic growth does not play a significant role in increasing Korea's digital service trade exports. However, the economic growth of trading partner countries can play a significant role in boosting the digital service trade in both China and Korea, and comparison shows that Korea has higher resilience in the digital services trade than China. In addition, the market size of target countries plays a positive role in promoting the digital service trade exports of both China and Korea, and the increase in the value-added share of services in target countries will lead to a decrease in the digital service trade exports of both China and Korea. Originality/value - This study is innovative in terms of research perspective and method. Academic research on the export potential of international trade has been extensive, but most studies are based on the perspective of the goods trade, fewer studies are based on the perspective of the service trade, and there are almost no studies based on the perspective of digital service trade. There is a gap based on the comparative analysis of the export potential of the digital service trade between China and Korea. This study extends the gravitational model of traditional service trade exports to digital service trade exports to comparatively analyze the export potential of China and Korea to RCEP countries. This study addresses this limitation by analyzing a comparative analysis of the digital service trade export potential of China and Korea.

• Journal of the Korea Convergence Society
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• v.9 no.7
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• pp.213-222
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• 2018

This study attempts to empirically investigate the excess returns of growth stocks in the Korean stock market comparing with those of value stocks. Recently, a few of IT and bio-pharmaceutical stocks with high growth potentials have accomplished dramatically high returns in the Korean stock market. Whereas, important prior studies in this line have observed negative excess returns from investment of growth stocks on average. And a few studies have reported that the distribution of excess returns from growth stocks is not normal but positively skewed. Empirical results of the present study are consistent with those of prior studies. Interestingly, the present study observed serial inverse correlation between excess returns of growth stocks and value stocks. Also, regardless of growth or value stocks, the stocks with higher PEG(=PER/ROE) showed higher excess returns.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.2
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• pp.142-147
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• 2015

The artificial light sources for growth of plant are usually high-pressure sodium lamp, metal haloids lamp, and fluorescent light; however, these light sources have relatively weaker Red and Blue lights that are necessary for growth of plants. Especially the effect of Photosynthetic Photon Flux Density (PPFD) is pointed out as the weakness. Meanwhile, LED light source can be selected by specific wavelength to greatly improve the effect of PPFD. In this regard, this paper aims to investigate the promotion of plant growth by measuring photosynthetic photon flux density (hereafter referred to as PPFD) according to changes in light quality of the LED light sources. Towards this end, LED light sources for plant growth were produced with 4 kinds of mono-chromatic lights and 6 kinds of combined lights by mixing red, blue, green and white lights. A comparative analysis was conducted to investigate the effects of optical properties and PPFD on plants (green leaf lettuce) using the produced light sources. The results monochromatic light has fastest growth rate, but plant growth conditions have poor. This being so, mixed light is suitable for the green leaf lettuce.