• Restorative Dentistry and Endodontics
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• v.29 no.4
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• pp.378-385
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• 2004

The purpose of this study was to compare the effects of preparation with GT files and profiles .04 in shaping of root canals and reconstruct the three-dimensional root canal system using micro computed tomography 40 canals of the extracted human mandibular molars were used, and randomly distributed into two experimental groups. In group 1. canals were prepared by GT files. In group 2, Profiles .04. were used. Apical preparation size was #30. For each tooth pre and post operative cross-sectional images were obtained by the micro CT at 50 micron intervals. Pre and post operative cross-sectional images of 1, 2, 3, 5, and 8mm from the apex were compared. For each section. canal area and centering ratio were determined. For each tooth pre- and post-operative root canal volume from the furcation to the apex of the roots was calculated by three-dimensional image software. Following results were obtained: 1. At 8mm from the apex, area of dentin removed by GT rotary file was significantly larger than that by Profile .04. And at the other levels there was not a significant difference. 2. There was a trend for GT rotary file to remain more centered in the canals than Profile .04 at all levels. But at 3mm level. there was a statistically significant difference. 3. In root canal volume increments after instrumentation, there was no significant difference between two groups.

• Korean Journal of Materials Research
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• v.4 no.2
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• pp.136-142
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• 1994

Epitaxial TiSiz films have been grown by UHV deposition of Ti on atomically clean Si(ll1)- orientated substrates. The Ti film of 50$\AA$ was deposited on the reconstructed Si(ll1) surface at room temperature. The sample was annealed up to $800^{\circ}C$ in $100^{\circ}C$ increments. The structure of the TiSiL films have been identified as the C49 metastable phase by electron diffraction patterns. Scanning electron microscopy( SEM) shows three different types of Tiksilicide island morphologies. The individual island structures are single crystal and are considered to be epitaxy with different crystallographic orientations. The orientational relationships of the $TiSi_{2}$ islands is given by [ 172 1 C49 $TiSi_{2}$//[110] Si and (021) C49 $TiSi_{2}$// (111)Si.

• Analytical Science and Technology
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• v.16 no.6
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• pp.431-437
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• 2003

Metalization yield of uranium oxide to uranium metal from lithium reduction process of spent pressurized water reactor (PWR) fuels was measured using thermogravimetric analyzer. A reduced metal produced in the process was divided into a solid and a powder part, and each metalization yield was measured. Metalization yield of the solid part was 90.7~95.9 wt%, and the powder being 77.8~71.5 wt% individually. Oxidation behaviour of the quartemary alloy was investigated to take data on the thermal oxidation stability necessary for the study on dry storage of the reduced metal. At $600{\sim}700^{\circ}C$, weight increments of alloy of Mo, Ru, Rh and Pd was 0.40~0.55 wt%. Phase change on the surface of the alloy was started at $750^{\circ}C$. In particular, Mo was rapidly oxidized and then the alloy lost 0.76~25.22 wt% in weight.

• Journal of Powder Materials
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• v.23 no.2
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• pp.108-111
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• 2016

$Y_2O_3-H_3BO_3:Eu^{3+}$ powders are synthesized using a mechanical alloying method, and their photoluminescence (PL) properties are investigated through luminescence spectrophotometry. For samples milled for 300 min, some $Y_2O_3$ peaks ([222], [440], and [622]) and amorphous formations are observed. The 300-min-milled mixture annealed at $800^{\circ}C$ for 1 h with Eu = 8 mol% has the strongest PL intensity at every temperature increase of $100^{\circ}C$ (increasing from 700 to $1200^{\circ}C$ in $100^{\circ}C$ increments). PL peaks of the powder mixture, as excited by a xenon discharge lamp (20 kW) at 240 nm, are detected at approximately 592 nm (orange light, $^5D_o{\rightarrow}^7F_1$), 613 nm, 628 nm (red light, $^5D_o{\rightarrow}^7F_2$), and 650 nm. The PL intensity of powder mixtures milled for 120 min is generally lower than that of powder mixtures milled for 300 min under the same conditions. PL peaks due to $YBO_3$ and $Y_2O_3$ are observed for 300-min-milled $Y_2O_3-H_3BO_3$ with Eu = 8 mol% after annealing at $800^{\circ}C$ for 1 h.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.5342-5348
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• 2014

Slope stability analyses were conducted to investigate the limitations of application of the standard inclination of slope and the effects of the berm width on the slope stability. The standard slope inclination could be applied to the basic slope sections that were considered for the analyses, whereas additional slope stability analysis should be performed for the case of considering ground water. A comparison of the factors of safety between the case of installing a berm and the case of letting the grading have an equivalent section area with the case of installing the berm, the factors of safety in the case of installing a berm were greater than those for the case of allowing grading, and the differences between the factors of safety increase with increasing berm width. For all the sections considered in the analyses, the increments of the safety factor were proportional to the width of the berm and those corresponding to the embankment slope and cut slope with a berm width of 7m were 34.5% and 48%, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.2
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• pp.134-140
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• 1992

Carrot(Daucus carota L.) seeds (CV Danver 126) were primed and then separated by density differences to improve both the percentage and time of radicle emergence. Seeds for priming were soaked in aerated distilled water for 2 days (water imbibed), 25% solution of polyethylene glycol(PEG) 6000 for 6 or 10 days, salt solution of 0.2M KNO$_3$＋0.1M $K_2$HPO$_4$ for 6 or 10 days, or mixed with Agro-Lig with 90% moisture content for 6 days and 70% moisture content for 6 or 10 days (SMP) at 2$0^{\circ}C$, respectively. The greatest embryo growth and the highest radicle emergence were observed from the seeds treated SMP with 90% moisture content for 6 days among the primed treatments. After the SMP treatment, the seeds were separated into density classes with a float-sink procedure using aqueous solution of Maltrin 600 with 0.02/cm$^3$ density increments. The lower density classes of the carrot seeds, the more embryo growth, the higher and the faster rates of radicle emergence were exhibited in order from 1.06 to 1.14 density classes of the carrot seeds treated SMP.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.8 s.145
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• pp.1102-1113
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• 2005

The propose of this study is to develop the optimal sizing system of ready-to-wear f3r elementary school girls using a newly invented statistical technique. The body measurements was classified by the method that equalizes the distribution of the subjects using the probability density function, to theoretically systemize a method to determine a size range of ready-to-wear for elementary school girls between 6 to 12 years old. The statistical method were 1) The total of 11 height groups, which size interval from one another is 6 cm that is an average height gap between each age. 2) In order to determine an approximate figure (m ${\times}$ n) to establish the appropriate sizes far each height group that fit to the combinations of bust and hip girth, which based on their means and standard deviations on the probability density curve to produce the standard normal distribution. 3) m and n were aligned by 4cm -the grading increments used for patterns making- and determined the size ranges by confirming the approximate figures of m and n. 4) The representative values were determined by an area ratio calculated by dividing the area determined from the range of bust and hip girth with the representative value. Considering the characteristics of subjects' distribution, the area ratios was used. 5) Weight was calculated by seeking a growth exponent for each age and multiplying it by the number of girls that fit to each size range. As sections that show the highest weight are more likely sought by the consumers, these sections were determined as the optimal size standards. 6) This optimal sizing system consists of sizes determined by the optimal size standards and its sizes are marked with height, bust and hip girth.

• Journal of The Korean Society of Grassland and Forage Science
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• v.7 no.2
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• pp.103-108
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• 1987

The experiment was carried out to determine the optimum application rate of liquid waste from methane fermentation (LW) and its effect on botanical composition, dry matter yields and nutrient quality of pasture mixtures. Experimental fields was designed as a randomized block treated with NPK chemical fertilizer (NPK = 28-20-24 kg/lOa), NPK + Water 28 ton, 112 NPK + LW 28 ton, 112 NPK + LW 42 ton, LW 28 ton, LW 42 ton and LW 56 ton/lOa at Livestock Experiment Station in Suweon, 1985. The results obtained are summarized as follows: 1. Vegetation of introduced pastures, both in grasses and legumes, was markedly increased in the plots treated with methane-liquid waste. However, heavy application of liquid waste tended to increase of native weeds such as Polygronum spp., Rumex spp. and Lactuca spp. 2. Crude protein contents was increased in the plants applied with liquid waste, but NFE was decreased compared with those of chemical fertilizer applied. The concentrations of crude fat and crude fibre were, however less affected by the fertilizer resource. Among cell-wall constituents, cellulose content was decreased as the liquid waste application rate increased, while hemicellulose showed a negative association. 3. Productivity of the pasture was increased as the liquid waste application rate increased. The highest dry matter yields was obtained in the plot treated with LW 42 ton/lOa by 71 1 kg/lOa, which shows about 71% increments compared with those of chemical fertilizer treated. Net energy yields, both in starch value and NEL, were also markedly increased under liquid waste application. As a results, the optimum application rate of methane-liquid waste was found to be 42 ton in 10 a.

• Journal of The Korean Society of Integrative Medicine
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• v.4 no.2
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• pp.23-28
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• 2016

Purpose : The purpose of this study was to investigate the effects of transverse abdominal muscle contraction on pulmonary function in supine position. Methods : 10 female and 10 male college students were recruited this study. Pulmonary Function test was measured with QUARK SPIRO. To check the changes in lung function with transverse abdominal muscle contraction, we tested pulmonary function in the supine, with and without transverse abdominal muscle contraction. While the transverse abdominis was activating, we investigate in the change of forced expiration. All statistical analyses were performed using SPSS Statistics VER.12.0 for window version p-values less than 0.05 were used to identify significant differences. Statistical analysis was used Paired t-test to know difference between activated and non-activated TrA of forced expiration. Results : The subject with transverse abdominal muscle contraction showed significant increments in variable of FVC, FEV1, PEF compared to the pre-intervention results (p<0.01). Conclusion : These results indicate that spontaneous contraction of the TrA helps pulmonary function. And the selective contraction of the transverse abdominis at the end of forced inspiration makes increases in the lung capacity.

• Korean Journal of Agricultural Science
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• v.40 no.2
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• pp.123-129
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• 2013

An experiment was conducted to evaluate the effects of nitrogen supplementation through urea-molasses multinutrient block (UMMB) on the performance of dairy cows fed good quality forage based diets with rice straw as a night feeding. A total of 10 multiparous crossbred dairy cows in their early lactation were grouped into two categories based on their breed, parity, body weight, milk yield, milk fat and protein contents and daily fed a chopped CO-3 grass (Pennisetum purpureum ${\times}$ Pennisetum americanum; hybrid Napier) ad-libitum, 1 kg of dairy cow concentrate feed during the day time and 5 kg of rice straw (dry matter basis) at night as the basal diet (control) for 5 wk. In addition to the basal diet, the treatment group received 300 g of crushed UMMB daily throughout the experimental period. Cows were milked twice daily and the milk yields were recorded. Milk and feed samples were collected weekly for chemical analysis. Supplementation of UMMB had no significant effects (p>0.05) on straw intake, daily milk yield, contents and yields of milk constituents such as milk fat, protein, lactose and solids-non-fat. In addition, milk urea nitrogen content were not affected (p>0.05) by UMMB supplementation. However, numerical increments in all the parameters measured were observed during the study in cows fed diets supplemented with UMMB. It can be concluded that nitrogen supplied through UMMB had no effects on production performances of dairy cows in this study.