• Journal of the Korean Geosynthetics Society
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• v.16 no.2
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• pp.121-129
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• 2017

There have been a number of water and sewer pipe breakdown reports followed by ground subsidence. Also, the excavating works for construction due to overcrowding of city have been common. Particularly, in urban areas ground becomes unstable because of the lowered lifeline sinkage followed excavation and backfilling. In order to solve the problem, some reinforcement works for ground by rod tamping or grouting have been applied. However, it is hard to predict when the buried utilities in underground will be damaged. Also, there is a limit for the underground exploration and investigation methods. Therefore, in this study, the estimated about the water soluble polymer pouch including poor mixed admixture which is designed to eliminate the dangerous factors. The reinforcement strength of this method was confirmed by verifying three points: meltiness in a certain period, water solubility in the ground water level, and characteristics of the pouch, which can be stored in daily conditions. It is also proved that this method allows to keep the ground from getting weakened in the installation of water and sewer pipe along with back filling materials.

• Archives of Plastic Surgery
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• v.34 no.2
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• pp.163-168
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• 2007

Purpose: The flap delay is a widely used technique to increase the flap survival. Dexamethasone is a well-known drug to have a positive impact on the flap survival. The objective of this study is to investigate the dual synergic effect of epinephrine as a chemical delay agent plus dexamethasone on the TRAM flap survival in rat model. Methods: Forty Sparague-Dawley rats were divided into 4 groups evenly and a right inferior epigastic vessel pedicled TRAM flap, sized $5.0{\times}3.0cm$, was elevated on each upper abdomen. In the control group(N=10), 2 ml saline was injected on transverse abdominis muscle for a week before the flap elevation. In surgical delay group(N=10) all superior pedicles and left inferior pedicle were ligated a week before the flap elevation. In epinephrine group (N=10), 1 : 50000 epinephrine mixed saline was injected to transverse abdominis muscle every day for a week before flap elevation. In epinephrine plus dexamethasone group (N=10), the same procedure as that of epinephrine group was conducted for a week and 2.5 ml/kg dexamethasone was injected transverse abdominis muscle 2 hours before the flap elevation. On the seventh day after flap elevation, the survival area of flaps were measured and the vessel numbers in upper dermis of flap were counted through histologic slides. Results: The results were as follows: the mean percentage of the flap survival area of surgical delay group ($60.5{\pm}2.44%$), epinephrine group ($75{\pm}4.43%$), and epinephrine plus dexamethasone group ($87{\pm}1.94%$) were higher than that of the control group ($35{\pm}6.06%$) significantly(p<0.05). In case of the vessel number though histologic slides, epinephrine group ($79.3{\pm}5.57$) and epinephrine plus dexamethasone group ($96.3{\pm}14.05$) were higher than that of the control group ($44.8{\pm}8.82$) significantly(p<0.05), but the surgical delay group ($54{\pm}4.23$) showed no significant difference (p>0.05) compared to that of the control group. Conclusion: The results indicated that epinephrine plus dexamethasone injection before the flap elevation could be used to increase the TRAM flap survival area in rat model.

• Journal of Chest Surgery
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• v.30 no.6
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• pp.598-606
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• 1997

Among 136 patients having undergone mitral valve surgery from September of 1994 through August of 1995 in Sejong Heart Institute, forty four patients(18 males, 26 females) underwent mitral valve reconstruction using prosthetic rings and their clinical results were evaluated. Patients'ages ranged from 5 to 63 years(mean age 38.2 years). Mitral valvular diseases were due to rheumatic origin in 30 patients(68%), degenerative in 13(30%), and congenital in one patient(2%). Mitral regurgitation(MR) was in 33 patients(76%), mitral stenosis 2(5%), and mitral stenoinsufaciency 9 patients(19%). The patients were divided into Carpentier's functional groups : type I, 5 patients(11%) : type I, 24 patients(55%) ; type III, 4 patients (9%) i and mixed(II + III), 11 patients(25%). Average number of anatomic lesions of mitral valve per patient was 3.7. The techniques included prosthetic ring amluloplasty(44 patients, 32 Carpentier ring and 12 Duran ring), leaflet mobilization(24, 55%), chordae shortening(23, 52%), chordae transposition(23, 52%), commissurotomy(16, 35%), leaflet resection(9, 20%), papillary muscle splitting(8, 18%), and chordae reimplantation(1, 2%). Average 3.4 surgical procedures were applied on mitral valve per patient. There were two hospital mortality and one reoperation due to development of MR(grade III) after 2 weeks. During the mean follow up of 12 months, patients improved in terms of functional class of the New York Heart Association, which was mean 3.0 preoperatively and 1.3 postoperatively. Doppler echocardiographic studies showed adequate valve area(2.07$\pm$0.11 cm2 mean $\pm$standard error), improved ventricular contractiliy in 41 patients(93%), ab ence of MR in 23(53%), trace MR in 18(42%), and garde II MR in 2 patients(5%).

• Journal of the Korean Vacuum Society
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• v.12 no.4
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• pp.263-268
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• 2003

Precise thickness control and excellent properties of silicon nitride thin films are essential for the next-generation semiconductor and display devices. In this study, silicon nitride thin films were deposited by batch-type atomic layer deposition (ALD) method using $SiC1_4$ and $NH_3$ as the precursors at temperatures ranging from 500 to $600^{\circ}C$. Thin film deposition using a batch-type ALD reactor was a layer-by-layer atomic growth by self-limiting surface reactions, and the thickness of the deposited film can be controlled by the number of deposition cycles. The silicon nitride thin films deposited by ALD method exhibited composition, refractive index and wet etch rate similar with those of the thin films deposited by low-pressure chemical vapor deposition method at $760^{\circ}C$. The addition of pyridine mixed with precursors increased deposition rate by 50%, however, the films deposited with pyridine was readily oxidized owing to its unstable structure, which is unsuitable for the application to semiconductor or display devices.

• Current Research on Agriculture and Life Sciences
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• v.20
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• pp.99-105
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• 2002

To develop good soybean varieties for sprouts. 285 indigenous lines and 16 recommending varieties were evaluated by the sprout and agronomic characteristics. The range of whole length, hypocotyl length, root length, and yield rate of sprouts was 9.5~23.0cm, 5.9~15.1cm, 3.2~9.2cm, and 121~695%, respectively. Yield rate of sprouts was the highest, 409%, in the lines of mixed seed coat color. At the same time, it was reversely proportional to seed weight : the smaller the seed weight, the higher the yield rate as in all other reports. The number of roots was significantly fewer in the lines of the black and the green seed coat color than others. Based on whole length, rate of root length, and yield rate of sprouts, many indigenous lines were evaluated much better than recommending varieties. In the hypocotyl color of sprouts, the brightness was higher in improved variety than indigenous lines but vice versa in redness and yellowness in general.

• Restorative Dentistry and Endodontics
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• v.35 no.6
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• pp.479-485
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• 2010

Objectives: The aim of this study was to compare the push-out bond strengths of resin cement/fiber post systems to post space dentin using different application methods of resin cement. Materials and Methods: Thirty extracted human premolars were selected and randomly divided into 3 groups according to the technique used to place the cement into root canal: using lentulo-spiral instrument (group Lentulo), applying the cement onto the post surface (group Direct), and injecting the material using a specific elongation tip (group Elongation tip). After shaping and filling of the root canal, post space was drilled using Rely-X post drill. Rely-X fiber post was seated using Rely-X Unicem and resin cement was light polymerized. The root specimens were embedded in an acrylic resin and the specimens were sectioned perpendicularly to the long axis using a low-speed saw. Three slices per each root containing cross-sections of coronal, middle and apical part of the bonded fiber posts were obtained by sectioning. The push-out bond strength was measured using Universal Testing Machine. Specimens after bond failure were examined using operating microscope to evaluate the failure modes. Results: Push-out bond strengths were statistically influenced by the root regions. Group using the elongation tip showed significantly higher bond strength than other ways. Most failures occurred at the cement/dentin interface or in a mixed mode. Conclusions: The use of an elongation tip seems to reduce the number of imperfections within the selfadhesive cement interface compared to the techniques such as direct applying with the post and lentulospiral technique.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.947-953
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• 2017

In this study, the regeneration efficiency of the amino acid salt absorbent which can be applied to carbon dioxide absorption / regeneration process was confirmed. The regeneration efficiency has a great influence on the economical judgment of the process. so, continuous regeneration experiment was conducted to establish economical process. The amino acid salts used in the experiments are Potassium L-lysinate and Potassium L-alaninate. Each amino acid and potassium hydroxide(KOH) were mixed at a 1: 2 molar ratio. In order to confirm the regeneration efficiency of the absorbent, carbon dioxide was absorbed in the two materials, and the carbon dioxide desorption experiment was carried out by heating. The initial reaction rate was L-alanine was faster. Over time, L-lysine, desorption higher concentrations of carbon dioxide. L-lysine showed higher regeneration efficiency than L-alanine, (L-alanine 47.26% and L-lysine 62.11%). As a result of the continuous regeneration experiment using the L-lysine having good absorption and regeneration efficiency, it was confirmed that the regeneration efficiency decreases as the number of regeneration increases.

• Resources Recycling
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• v.27 no.4
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• pp.50-56
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• 2018

For the purpose of optimizing the counter current extraction process for separation of [Pr, Nd, Sm] group and [La] in mixed solution using Cyanex 572 as an extractant, the theory of Xu Guangxian was derived for calculating the optimized extraction factors. From the basic batch test result, the separation factor was 16.80 at extraction process and 21.48 at scrubbing process, and the loading capacity of 1.0 M Cyanex 572 was 0.12 M of rare earth element. The process parameters such as the stage number at extraction and scrubbing process, the flow rate ratio of feed and solvent solution can be calculated using an equation of optimum extraction ratio proposed by Xu Guangxian. From the result of calculation, 7 extraction stages and 4 scrubbing stages were required for rare earth separation, and the flow rate ratio of feed solution, solvent solution, scrubbing solution was 25 : 5.67 : 12.27.

• Cross-Cultural Studies
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• v.29
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• pp.341-366
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• 2012

'Headline Database of Newspaper Articles' is a database which contains about 141,500 newspaper articles from 1949 to March, 2009. They are collected from two perspectives; 'language' and 'language life' by KOKKEN. There were 3312 newspaper articles (about 2.34%) which included the word ONNA at 'Headline Database of Newspaper Articles'. The number of newspaper articles related to ONNA started to increase in 1975 but they decreased afterwards. They increased rapidly in 1980 and maintained the condition. However, they started to decrease rapidly in 1990 and maintained the decreased condition. They increased rapidly again in 2004 and 2007. The main causes of rapid increase were the commercial message of instant noodles "I am the one who is making. I am the one who is eating." in 1975, newspaper articles related to "Starting of full-scale studies on female language" in 1980, comments of "active women" and "men's crime" related to a murder case of an elementary school student in Sasebo City and mixed attendance books in 2004, a comment of "Women are machines which give birth to babies" in 2007. Those six causes of rapid increase suggested that the perception of gender such as 'Men need to work outside and Women need to do housework and take care of child' which was fixed until then was changing and becoming a stereotype of virtual reality rather than reality. The vocabulary related to ONNA appeared 3411 times among 3312 newspaper articles which included ONNA. Typical forms of the vocabulary related to ONNA were and . They appeared 2390 times and occupied 70% of the whole data. (3411 times) The form of ONNANOKO among the vocabulary related to ONNA appeared 113 times and occupied a high rate. ONNANOKO(113) and other words such as SHOJO(115), JOJI(28), YOJO(9) (152 in total) implied that appearing of young women at newspaper articles were increasing. Also, the vocabulary related to 'female language' such as ONNAKOTOBA(28) ONNANOKOTOBA(10) and a woman's heart such as ONNAGOKORO(35) and ONNANOKIMOCHI(34) appeared frequently. The vocabulary related to JOSEI were divided into <$JOSEI^{**}$> and <$^{**}JOSEI$>. <$JOSEI^{**}$> were mainly related to an occupation. <$^{**}JOSEI$> were mainly used to express women by regional groups such as or combined with modifiers to express women such as . In case with modifiers, WAKAIJOSEI appeared 35 times and showed the highest frequency. It had negative evaluations in many cases. The vocabulary related to JOSI appeared on the form of <$JOSI^{**}$> and mainly associated with 'a girl's school' and 'a female student'.

• Journal of agriculture & life science
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• v.44 no.2
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• pp.49-56
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• 2010

Yogurt base was prepared from skim milk added with 0.1, 0.3 and 0.5% (w/v) garlic powder and fermented with Lactic acid bacteria (the mixed strain of Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus) at $42^{\circ}C$ for 24 h. The yogurt products were evaluated for acid production such as pH and titrable acidity, number of viable cell, viscosity, color value and sensory properties. The titrable acidities of yogurt added with garlic powder were higher than that of control(0.73%). There was no significant difference in viable cell counts among samples except 0.3% garlic powder. The viscosity of 0.5% garlic yogurt was the highest than any other garlic yogurt. There was no significant difference in color difference among experimental groups. The overall sensory scores of yogurt added with 0.1% and 0.3% garlic powder were not significantly different with those of control. These results suggest that the added amounts of garlic powder to prepared yogurt are adequate below 0.3%.