• Journal of the Korea Concrete Institute
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• v.15 no.6
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• pp.769-777
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• 2003

The strengthening of concrete structures in situ with externally bonded carbon fiber is increasingly being used for repair and rehabilitation of existing structures. Because carbon fiber is attractive for this application due to its good tensile strength, resistances to corrosion, and low weight. Generally bond strength and behavior between concrete and carbon fiber mesh(CFM) is very important, because of enhancing bond of CFM. Therefore if bond strength is sufficient, it will be expect to enhance reinforcement effect. Unless sufficient, expect not to enhance reinforcement effect, because of occuring bond failure between concrete and CFM. In this study, the bond strength and load-displacement response of CFM to the concrete by the direct pull-out test(the tensile-shear test method) were investigated using the experiment and the finite element method analysis with ABAQUS. The key variables of the experiment are the location of clip, number of clips and thickness of cover mortar. The general results indicate that the clip anchorage technique for increasing bond strength with CFM appear to be effective to maintain the good post-failure behavior.

• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.1
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• pp.59-68
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• 2010

Recently, dental implants extensively inserted on edentulous area show highly clinical success rate. However, clinicians cannot exclude the possibility of failure and it often unexpectively occures. Many possible factors associated with failure of dental implants have been reported but controversy exists over the extent to them. In this study, we collected 212 patients who had been inserted 358 dental implants on mandibular premolar and molar area from 2005 to 2006. The survival rate of fixtures was recorded according to age of patients, implantation site, implant system, diameter and length of fixtures. Multi-variable analysis using SPSS chi-square test was operated to verify relation of each factors and survival rates. Accumulative survival rate was 98.3% for 3 years. Only diameter of fixtures was related to the implant survival rate. This may be thought that wider fixtures had been chosen to rescue implants or used in sites of poor bone quality. Further continuous study will be needed for direct guidance associated with survival rate of implants.

• Journal of the korean academy of Pediatric Dentistry
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• v.33 no.4
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• pp.624-632
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• 2006

In recent years, xenon plasma arc lamp was introduced for high-intensity curing of composite filling materials in direct resin restorations. In this study, two types of restorative materials, namely composites point $4^{(R)}$ and $Z250^{(R)}$ were selected and curing was conducted using a conventional halogen light and two plama curing lights. Two different resin composites were cured using the different units($Flipo^{(R)}$, Ultra-lite 180A, and $TriLight^{(R)}$) and tested for microhardness. The purpose of this study was to test the hypothesis that exposure to a plasma curing lamp for 3, 6. 9 seconds is equivalent to 20 or 40 seconds of irradiation using a conventional halogen curing unit. 1. $Flipo^{(R)}$ and Ultra-lite 180A were able to polymerize point $4^{(R)}$ at 6 seconds to a degree equal to that of the $TriLight^{(R)}$(control) at 40 seconds. 2. $Flipo^{(R)}$ was able to polymerize $Z250^{(R)}$ at 9 seconds to a degree equal to that of the $TriLight^{(R)}$(control) on the bottom surface at 20 seconds. whereas Ultra-lite 180A could not do. 3. Two plasma curing units were able to cure the test-composites with bottom/top ratios approximately 61% to 96% at 3 to 9 seconds. There were some differences between the two composite brands, with $Z250^{(R)}$ displaying less difference between top and bottom hardness values. For point $4^{(R)}$ and $Z250^{(R)}$, at least 6 or 9 seconds were necessary to produce microhardness equivalent to that of the $TriLight^{(R)}$ curing at 20 or 40 seconds.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1619-1629
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• 2013

It turned out that there was a direct or an indirect relationship among global warming, urban heat island effects, urban and traffic environments, and public's health. In particular, unusual climate phenomena such as frequent heavy rainfall and scorching heat in a row that had rarely happened before have a negative effect on quality of life for people living in urban areas. This study focuses on the effects of roadway geometric design and traffic conditions on air temperature of roadside in Seoul Metropolitan Areas, controlling of roadway micro-climate environment. Five roadway segments containing different roadway and traffic conditions in terms of traffic median with trees, street trees, traffic volume and average travel speeds were surveyed. According to statistical results(t-test) from three roadway air temperature regression model estimations, air temperature is found to be different from one another in three periods-morning, afternoon and evening. Regarding roadway geometric design, air temperature of urban roads with vegetated median strips is lower about 1.3~2.2 degrees in celcius. Higher traffic volumes per lane and lower average travel speeds will tend to increase roadside air temperature, and efficient traffic operation policies can protect from increasing roadside air temperature in urban areas.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.5
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• pp.1199-1205
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• 2009

The purpose of this case-control study was done to examine the relationship among the cerebral infarction, blood lipids and homocysteine. We compared the components of blood lipids and homocysteine between cerebral infarction patients group (n=127) and controls group (n=158). We performed Pearson's chi-square test and Student's t-test for univariate analysis, Binary logistic regression for multivariate analysis to evaluate risk factors of cerebral infarction and Pearson's correlation analysis to investigate correlation between blood lipids and homocysteine. The results were as follows. The blood levels of High density lipoprotein cholesterol(HDL-Chol) and Low density lipoprotein cholesterol (LDL-Chol) were significantly lower in patients group, while age, the blood levels of Triglyceride(TG) and homocysteine were significantly higher in patients group. Hypertension had a 4.62 odds ratio, $TG{\geq}150\;mg/d{\ell}$ had a 2.33 odds ratio, HDL-Chol ${\leq}40\;mg/d{\ell}$ had a 6.85 odds ratio, but sex, DM, T-Chol, LDL-Chol had no direct relationship with odds ratio(non significant). In addition, among T-Chol and TG , HDL-Chol, LDL-Chol, they had positive correlation each other. Between TG and HDL-Chol had negative correlation each other. Homocysteine was not correlated with blood lipids adjusted for age and sex. These results suggest that low HDL-Chol and high TG may be risk factor of cerebral infarction. The correlation between homocysteine and blood lipids was not proven.y urther reserch on the subject is needed.

• Korean Journal of Poultry Science
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• v.35 no.1
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• pp.9-13
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• 2008

Salmonella enterica serotype gallinarum biovar Gallinarum or Pullorum and Salmonella enterica serotype Enteritidis are the most important diseases in poultry industry. Transitional diagnosis methods of these diseases such as direct isolation and identification by a biochemical test are time consuming with low specificity. In this study, we have focused on the suitable procedure for the rapid and accurate diagnosis of diseases derived from the three Salmonella strains. We initially confirmed Salmonella species by PCR using a specific ITSF/ITSR primer pair instead of biochemical test, and then the PCR-amplified phase 1 flagellin (fliC) using a specific fliCF/fliCR primer pair was digested with a restriction endonuclease, Bpm I and/or Bfa I, to discriminate among S. Pullorum, S. Gallinarum, and S. Enteritidis. We found that these methods could be applied to field isolates of the three Salmonella strains to detect and to discriminate rapidly for convenient diagnosis.

• The Korean Journal of Nuclear Medicine
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• v.31 no.4
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• pp.440-451
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• 1997

This study was designed to prospect the $^{111}In$-labelled paclitaxel as tumor imaging agent. In order to provide a taxol molecule with a functional group which is able to chelate In-111, taxol-DTPA conjugate and 2'-hemisuccinyltaxol were synthesized by esterification of taxol at C-2'on C-13 carbon with DTPA anhydride and succinic anhydride, respectively. Synthesis yield of the taxol derivatives was 34% for taxol-DTPA and 80% for 2'-hemisuccinyltaxol. Cytotoxicity of the taxol derivatives were measured by MTT method toward cell lines HT29, B16, P388, and CT26. The cytotoxic activities of the taxol derivatives were maintained, although less active than taxol. Radiolabelling of the taxol derivatives were proceeded directly with $^{111}InCl_3$ or indirectly with $^{111}In$-citrate(ligand-exchange method). The ligand-exchange method was not suitable because some precipitates appeared during the reaction. On the contrary, by direct radiolabelling method, we were able to obtain taxol-DTPA-$^{111}In$ in 100% radiochemical yield. However, 2'-hemisuccinyltaxol was not labelled by both methods. Yield and radiochemical purity of the radiolabelled com-pound were determined by HPLC, paper chromatography and instant thin layer chromatography. Taxol-DTPA-$^{111}In$ was characterized to be hydrophilic by lipophilicity test, and nearly non-adhesive to HT29, B16, P388, and CT26 by cell binding affinity test. Binding affinity of the taxol-DTPA-$^{111}In$ complex to serum proteins was also examined by protein precipitation with 30% trichloroacetic acid. The results showed that 30% of the taxol-DTPA-$^{111}In$ complex binds with serum proteins.

• Journal of Energy Engineering
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• v.25 no.4
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• pp.159-169
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• 2016

In this study, the effects of MTBE contents as oxygenates in gasoline on exhaust emissions and fuel economy in MPI and GDi vehicles have been investigated. Various oxygen contents have been selected such as 0, 1.0, 2.3 and 2.7 wt%. FTP-75 and HWFET modes as fuel economy test methods which are widely used in Republic of Korea and US were applied to investigate exhaust emissions from the test vehicles. Emissions of CO, NMHC and NOx did not show significant correlation with oxygen contents in gasoline fuels, although having slight difference with these contents. In addition, CO2 emissions were not significantly changed with respect to oxygen content. But in case of warm-up and FTP-75 and HWFET modes including high speed regimes, CO2 emissions showed inverse correlation with oxygen contents. Particulate number concentration was inversely proportional to the oxygen contents, having the minimum value at the condition of 2.3 wt%. In case of fuel economy through carbon balance method, the highest value has been obtained at 2.3 wt% and there was positive correlation with oxygen contents and fuel economy.

• Korean Journal of Organic Agriculture
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• v.21 no.1
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• pp.95-104
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• 2013

This research was performed to test the effects of oleic acid for the management of greenhouse whiteflies and tobacco whiteflies. Tobacco whiteflies, especially, are the vectors of tomato yellow leaf curl virus on tomato plants. Whiteflies are not only the vectors of various viruses but also the major insect pests that cause direct damages through sucking and induce sooty mold with their sweet dew on tomato plants. There are many eco-friendly management measures including the use of yellow sticky trap and natural enemies such as Eretmocerus eremicus and Amblyseius swirskii. However, these management measures have difficulties to implement in the greenhouse. Therefore, in this research, oleic acid was tested for its effect on the management of whiteflies at various concentrations of 1,000ppm, 2,000ppm, or 4,000ppm. As a result, treatments of 1,000ppm, 2,000ppm and 4,000ppm oleic acid showed the control value of 70%, 76% and 84%, respectively. In another test, treatments of 2,000ppm oleic acid, and control treatment of 1,5000ppm neem oil and 50ppm dinotefuran showed the control value of 82%, 75%, and 75%, respectively. Cost for one application of oleic acid and neem oil for 10a area would be 3,180 Won and 20,150 Won, respectively. As a result, it was assumed that the use of oleic acid would be a appropriate management measure.

• Korean Journal of Veterinary Service
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• v.18 no.1
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• pp.41-56
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• 1995

The present study was conducted to investigate results of B. anthracis isolated from Anthrax in the Kyong-Ju of Feb. 12. 1994. 1. In biochemical feature, B. anthracis was a gram-positive rod, non-motility, sporulation, capsulation. It was positive in gelatinase, starch hydrolysis, glucose. But negative in urease, arabinose, mannitol, xylose. 2. B. anthracis grew well on B4 Br A TSA after incubation for 24 hours. The organisim grew well on BA, Br. A, NA, TSA after incubation for 72 hours. The media grew well on Br A instead of BA. 3. On 5% blood agar by laboratory animal, ${\beta}$ -hemolysis was produced from 36 hours to 48 hours incubation. There was perfect ${\beta}$-hemolysis after incubation for 48 hours. On the other side ${\beta}$-hemolysis was begun on 5% goat blood agar after incubation for 60 hours. 4. In the test of antimicrobial susceptibility, B. anthracis was very sensitive to AM, CF, TE, ENR, GM, AN, DFX, S, P, TYLO, N, KM, C, E, Lins＋Sp, NN, CC, CFP, CB were sensitive one by one. B. anthracis was no-sensitive to L, XNL, TIA, CL, SXT 5. B. anthracis had never sensitivity to direct inoculation of rat and chicken, after subcutanous inj. It was very sensitive to mouse and goat, hamster, guinea pig, rabbit had a sensibility one by one. 6. The dead laboratory animal which had been inoculated with B. anthracis preserved at $37^{\circ}C$ incubation, B. anthracis didn't cultivate on non-dissected animal after 80 hours but cultivate on dissected animal after 360 hours. 7. The rapidly death could cause high concentration, died from 420 after S. C. 8. The blood smeared samples of hamster from inoculation with B. anthracis, spore germinated In 37$^{\circ}C$ after 5 hours, in $32^{\circ}C$ after 6 hours, in room temperature after 9 hours, in $-4^{\circ}C$ to $-20^{\circ}C$ after 10 hours. 9. B, anthracis inoculated to laboratory animal after SC or PO. Mice and rats feces didn't cultivated with B. anthracis after SC, but did cultivated with B. anthracis after PO. 10. In the test of disinfectant, B. anthracis was high effective to $HgC1_2$, formalin, effect phenol, cresol, but non-effect NaOH, ethanol.