• Journal of The Korean Society of Grassland and Forage Science
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• v.38 no.1
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• pp.44-52
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• 2018

This experiment was conducted at Suwon, Korea from 2013 to 2015. The objective of this study was to establish the optimum seeding rate, and to clarify the nitrogen fertilizer level for rye seed production in central and north area of Korea. We used Korean rye cultivar 'Gogu' for this test. We employed a split-plot design with three replications. The main plots were designed by three seeding levels (3, 5 and $7kg\;10a^{-1}$), but other sub-plots were randomly seeded. The plots were treated with three different nitrogen fertilizer levels (3, 6 and $9kg\;10a^{-1}$). The percentage of productive tiller, number of grain per spike, fertility rate, 1 liter weight, and 1000-grain weight decreased as seeding rate increased from $3kg\;10a^{-1}$ to $7kg\;10a^{-1}$, whereas the number of spike per $m^2$ increased. Therefore the grain yields of rye had less of an effect by increasing seeding rate. There was an increase in number of spike per $m^2$, number of grain per spike, and fertility rate as nitrogen fertilizer level increased from $3kg\;10a^{-1}$ to $9kg\;10a^{-1}$, but grain yields significantly not affected by the interaction of seeding rate ${\times}$ nitrogen fertilizer levels. However, the best seeding rate and nitrogen fertilizer level for rye seed production were 5 kg and $5{\sim}6kg\;10a^{-1}$, respectively, considering seed and fertilizer reduction and the prevention of pollution by excess fertilization.

• Progress in Medical Physics
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• v.12 no.2
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• pp.113-124
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• 2001

For veterinary imaging diagnosis, we obtained MR images of the canine brain, spine, kidney and pelvis from 3T MRI system which was equipped with the world first 3T active shield magnet. Spin echo (SE) and fast Spin Echo (FSE) images were obtained from the canine brain, spine, kidney and pelvis of normal and sick dogs using a homemade birdcage and transverse electromagnetic (TEM) resonators operating in quadrature and tuned to 128 MHz. In addition, we employed a homemade saddle shaped RF coil. Typical common acquisition parameters were as follows: matrix=512$\times$512, field of view (FOV)=20cm, slice thickness=3 w, number of excitations (NEX)=1. For T1-weighted MR images, we used TR=500 ms, TE=10 or 17.4 ms. For T2-weighted MR images, we used TR=4000 ms, TE=108 ms. Signal to noise ratio (SNR) of 3T system was measured 2.7 times greater than that of prevalent 1.57 system. The high resolution images acquired in this study represent more than a 4-fold increase in in-plane resolution relative to conventional images obtained with a 20 cm field of view and a 5 mm slice thickness. MR images obtained from 3T system revealed numerous small venous structures throughout the image plane and provided reasonable delineation between gray and white matter The present results demonstrate that the MR images from 3T system could provide better diagnostic quality of resolution and sensitivity than those of 1.5T system. The elevated SNR observed in the 3T high field magnetic resonance imaging can be utilized to acquire images with a level of resolution approaching the microscopic structural level under in vivo conditions. These images represent a significant advance in our ability to examine small anatomical features with noninvasive imaging methods. Moreover, MRI technique could begin to apply for veterinary medicine in Korea.

• Journal of dental hygiene science
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• v.7 no.3
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• pp.135-139
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• 2007

1. Recognition of subjects on oral health education, About the question if they know oral health education, those who said yes were 241(70.7%) and those who said no were 100(29.3%). And, about the question how they get to know oral health education, 161(47.2%) told they knew it by a kindergarten or a nursery, 115(33.7%) told by neighbors, 30(8.8%) told by a public health center, 28(8.2%) told by a dental clinic and 7(2.1%) told that they learned it by other methods. 2. The perception of subjects on oral health education, About the question if they executed oral health education in a kindergarten or a nursery, 254(74.5%) said yes and 87(25.5%) said no. And, about the question if they have ever executed oral health education out of a kindergarten or a nursery, 70(20.5%) said yes and 271(79.5%) said no. 3. Subjects' oral health behaviors and attitudes toward children, About the question if they have ever visited a dental office, 249(73.0%) said yes and 92(27.0%) said no. And, about the question if they watch their children's toothbrushing, 321(94.1%) said yes and 20(5.9%) said no. About the question if they examine if their children have decayed teeth, 213(62.5%) said yes and 128(37.5%) said no. And, about the question if they are interested in their children's oral health, 244(71.6%) said yes and 97(28.4%) said no. 4. It appeared that unemployed mothers executed oral health education to their children more compared with employed mothers(p < .01). 5. Execution of oral health education according to the recognition of oral health education and previous experiences of subjects, The execution of oral health education according to the recognition of oral health education was statistically significant(p < .001). 6. Execution of oral health education according to the subjects' oral health behaviors and attitudes toward children. The execution of oral health education according to the experience of visiting a dental office, watching children's toothbrushing and watching children's teeth was statistically significant(p < .01, p < .001).

• Clean Technology
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• v.10 no.2
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• pp.73-87
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• 2004

In most of industrial fields, cleaning is employed for removing soils on their products or parts. Halogenated cleaning agents such as CFC-113, 1,1,1-TCE(1,1,1-trichloroethane), MC(methylene chloride) and TCE (trichloroethylene) have been used as cleaning ones in most of companies in the world since their excellent performance of cleaning ability and good material compatibility. However, CFC-113 and 1,1,1-TCE which are ozone destruction substances are not used any more in the advanced countries because of the which are ozone destruction substances are not used any more in the advanced countries because of the Montreal protocol. MC and TCE are now used restrictively at small part of industrial fields in most of countries since they are known to be hazardous or carcinogenic materials. Thus, it is indispensible that the alternative cleaning agents which are environmental-friendly and safe, and show good cleaning ability should be developed or utilized for replacement of the halogenated cleaning agents. Aqueous/semi-aqueous cleaning agents are evaluated to be promising alternative ones among various alternatives in environmental and economical view point. In this study, commercially available 12 aqueous and 6 semi-aqueous cleaning agents were selected and their physical properties, cleaning abilities, rinsing abilities and recycling of contaminated rinse water were measured and analyzed. Aqueous cleaning agents with higher wetting index showed better cleaning ability compared with those with lower wetting index. However wetting index did not have any correlation with cleaning ability in semi-aqueous cleaning agents. It was observed that soil concentration in aqueous and semi-aqueous cleaning agents should be maintained below the certain concentrations which depend on types of clearing agents. More than 70% soils in contaminated rinse water by some of aqueous and semi-aqueous clearing agents could be separated by simple settling method. This means that some cleaning agents with high oil-water separation efficiency will be effiective for recycling oil-contaminated rinse water. It was found that contaminated rinse water with aqueous agents was purified easiy by ultrafiltration method with PAN membrane of 30 kDa.

• Korean Journal of Agricultural Science
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• v.36 no.1
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• pp.63-71
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• 2009

Two experiments were conducted to investigate feed value of Yukmijihwangtang (herbal medicine) meal. In experiment 1, the chemical composition of Yukmijihwangtang ingredients was determined before and after extraction, and investigated the effects of partial substitution of dried Yukmijihwangtang meal on TMR for fattening cattle. In experiment 2, nine Korean native male goats were employed to investigate the palatability and ruminal parameters of Yukmijihwangtang meal silages. In experiment 1, the crude protein content after water extraction was higher in Alisma orientale Juzepczuk (Teaksa), and lower in Pachyma hoelen Rumph (Bokryeong). the crude fat content after water extraction was higher in Cornus officinalis Sieb. et Zucc (Sansuyu), and lower in other ingredients. ADF content after water extraction of Cornus officinalis Sieb. et Zucc (Sansuyu) was higher compared to those of Pachyma hoelen Rumph (Bokryeong) and Paeonia suffruticosa Andrews (Mokdanpi). Dioscorea japonica Thunberg (Sanyak) was the lowest in ADF content. Dry matter disappearance was increased by adding Yukmijihwangtang meal to TMR. In experiment 2, feed intakes of Yukmijihwangtang silage containing molasses (0.5 and 1%) for 30 min and 6 hr were significantly higher than that of control (0%) in Korean native goats. In various ruminl parameters, molasses addition to silage materials trended to increase total VFA, propionate and valerate contents, but trended to decrease iso-butylate, butylate and iso-valerate contents in Korean native goats. In conclusion, Yukmijihwangtang meal could be used as partial substitution of low level in TMR for fattening cattle. Molasses supplementation to silage materials contained with herbal medicine meal could improve its nutritional quality and palatability for Korean native goats. One percent level of molasses addition could give a useful effect in ensiling.

• Management & Information Systems Review
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• v.34 no.3
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• pp.273-302
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• 2015

This empirical study analyzed the influence of transformational leadership on knowledge management activities and organizational commitment, and examined the mediating effect of knowledge management in the relationship between transformational leadership and organizational commitment. A survey was employed as the research method. The survey targeted 635 participants working in the service, manufacturing, and IT industries. The results were used to compare and analyze the relationships among industry-specific variables. Transformational leadership is defined as the tendency to strive for change and innovation despite the achievement of objectives, develop the potential capabilities and strengths that each member of the organization possesses, amplify their self-esteem and passion, and lead them to surpass their expected objectives by stimulating positive strengths. Such type of leadership has been perceived as a precedent that enhances organizational effectiveness. In summary, this study has yielded the following results: First, the transformational leadership exhibited by organizational leaders was found to have a significant positive impact on knowledge management activities as well as organizational commitment. Second, knowledge management activities were found to have a significant positive influence on organizational commitment. Third, the transformational leadership exhibited by organizational leaders was found to have a partial mediating effect on the mediating role of knowledge management activities in the relationship with organizational commitment. Fourth, analyzing industry-wise, the influence of transformational leadership on knowledge management activities was the most significant in the service industry, which was also the case for the influence of knowledge management activities on organizational commitment. The influence of leaders' transformational leadership on organizational commitment was the most significant in the information technology industry. Finally, based on the aforementioned research results, suggestions were made regarding the meaning of the influence of transformational leadership on knowledge management activities and organizational commitment and the differences by industry thereof, while also suggesting the limitations of this work.

• Korean Journal of Materials Research
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• v.11 no.5
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• pp.427-430
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• 2001

We prepared 10cm-diameter Si(100)/500 $\AA$-Si$_3$N$_4$/Si(100) wafer Pairs adopting 500 $\AA$ -thick Si$_3$N$_4$layer as insulating layer between single crystal Si wafers. Si3N, is superior to conventional SiO$_2$ in insulating. We premated a p-type(100) Si wafer and 500 $\AA$ -thick LPCVD Si$_3$N$_4$∥Si (100) wafer in a class 100 clean room. The cremated wafers are separated in two groups. One group is treated to have hydrophobic surface and the other to have hydrophilic. We employed a FLA(fast linear annealing) bonder to enhance the bond strength of cremated wafers at the scan velocity of 0.1mm/sec with varying the heat input at the range of 400~1125W. We measured bonded area using a infrared camera and bonding strength by the razor blade crack opening method. We used high resolution transmission electron microscopy(HRTEM) to probe cross sectional view of bonded wafers. The bonded area of two groups was about 75%. The bonding strength of samples which have hydrophobic surface increased with heat input up to 1577mJ/$m^2$ However, bonding strength of samples which have hydrophilic surface was above 2000mJ/$m^2$regardless of heat input. The HRTEM results showed that the hydrophilic samples have about 25 $\AA$ -thick SiO layer between Si and Si$_3$N$_4$/Si and that maybe lead to increase of bonding strength.

• Polymer(Korea)
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• v.30 no.6
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• pp.498-504
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• 2006

A suspension polymerization of styrene In aqueous phase was employed to study if polystyrene particles ranging from 1 to $20{\mu}m$ can be produced. Hydrophobic silica was selected as a stabilizer and azo-bisisobutyronitrile (AIBN) as an initiator. Polymerization reaction was carried out at a selected temperature in the range of $65{\sim}95^{\circ}C$. Stabilizer concentration was varied from 0.17 to 3.33 wt% compared to the water while the concentration of the initiator was raised from 0.13 to 6.0 wt% compared to the monomer. Dispersion of hydrophobic silica into the water phase was achieved by precise control of pH. Optimum dispersion of silica was obtained at pH 10. Average particle diameter decreased with increasing amounts of stabilizer concentration initially, exhibiting the minimum average diameter at 1.67 wt% of stabilizer concentration, after which it started to Increase. It is speculated that an excessive presence of stabilizer encouraged a secondary reaction in the reaction medium, which led to particle agglomeration, and as a result an increase in average particle diameter. Molecular weight was found to be independent of stabilizer concentration between 0.13 and 1.00 wt% whereas, it increased when stabilizer concentration exceeded 1.67 wt%. Variation of molecular weight was probably caused by the reduced activity and efficiency of initiator due to the high concentration of silica, and the secondary reaction in the reaction medium, as well. An increase in the Initiator concentration and/or reaction temperature resulted in an increase in both reaction rate and particle diameter. Consequently, we have confirmed that spherical polystyrene particles with $1{\sim}20{\mu}m$ in diameter can be prepared by careful selection of the concentration of stabilizer, initiator, pH and reaction temperature.

• Radiation Oncology Journal
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• v.22 no.1
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• pp.33-39
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• 2004

Purpose : A tumor registry system for the patients treated by radiotherapy at Samsung Medical Center since the opening of a hospital at 1994 was employed. In this study, the tumor registry system was introduced and the validity of the tumor registration was analyzed. Materials and Methods: The tumor registry system was composed of three parts: patient demographic, diagnostic, and treatment Information. All data were input in a screen using a mouse only. Among the 10,000 registered cases in the tumor registry system until Aug, 2002, 199 were randomly selected and their registration data were compared with the patients' medical records. Results : Total input errors were detected on 15 cases (7.5%). There were 8 error items In the part relating to diagnostic Information: tumor site 3, pathology 2, AJCC staging 2 and performance status 1. In the part relating to treatment information there were 9 mistaken items: combination treatment 4, the date of initial treatment 3 and radiation completeness 2. According to the assignment doctor, the error ratio was consequently variable. The doctors who 010 no double-checks showed higher errors than those that 010 (15.6%:3.7%). Conclusion: Our tumor registry had errors within 2% for each Item. Although the overall data qualify was high, further improvement might be achieved through promoting sincerity, continuing training, periodic validity tests and keeping double-checks. Also, some items associated with the hospital Information system will be input automatically In the next step.

• Journal of Life Science
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• v.24 no.3
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• pp.252-259
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• 2014

The leaves of Peatasites japonicus are a traditional oriental medicine with diverse biological activities. A simple and specific analytical method for the quantitative determination of bakkenolide B constituents from methanolic extract of the leaves of P. japonicus was developed. Bakkenolide B was isolated from the leaves of P. japonicus, and its structure was elucidated based on 1D, 2D NMR, and GC-MS spectral data. A liquid chromatographic method was developed to evaluate the quality of P. japonicus through determination of major active compound, bakkenolide B. The wavelengths at 254 and 215 nm were chosen to determine bakkenolide B. The recovery of the method was in the range of 98.6 to 103.1%, and bakkenolide B showed good linearity ($r^2$=0.999) within test ranges. The developed method was applied to the determination of bakkenolide B in the plant part and seasonal changes. The results showed that the content of bakkenolide B in the leaf was higher than in the petiole and rhizome. In this study, a simple, rapid, and reliable high-performance liquid chromatography method was used to determine the percentage and composition of bakkenolide B in P. japonicus procured from different Petasites species plants in South Korea. The method can be employed in routine quantitative analysis and quality control of different products in the market.