• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.19-23
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• 1991

The revised draft of IEC Publication 60 "High Voltage Test Techniques" introduced a new calibration system for impulse measurements. In order to corespond to this draft, development of reference measuring systems and investigation of comparison tests are being carried out in Japan. This paper is a preliminary report on the topic.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2001.05a
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• pp.128-128
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• 2001

Atrazine, one of herbicide widely used in agriculture, is classified as a possible human carcinogen (2B group) that may cause breast and ovarian cancers by IARC, and is known as an endocrine disrupter. Atrazine has been subjected to broad ranges of genotoxicity tests wi th predominantly negative results, but reported conflicting results across two or more independent tests as well. (omitted)

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.183-183
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• 2001

Atrazine, one of herbicide widely used in agriculture, is classified as a possible human carcinogen (2B group) that may cause breast and ovarian cancers by IARC, and is known as an endocrine disruptor. Atrazine has been subjected to broad ranges of genotoxicity tests with predominantly negative results, but reported conflicting results across two or more independent tests as well. This fact indicates that a more comprehensive genotoxicity assessment needs for atrazine.(omitted)

• Proceedings of the KSR Conference
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• 1998.11a
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• pp.96-102
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• 1998

The characteristics of roadbed are very important factors in the design of railways. Laboratory model tests were performed to investigate the effectiveness of geogrid placement in the subbase layers on reinforcement. Design parameters of reinforcement were determined through the laboratory model tests. The results indicated that geogrid reinforcement is increased the bearing capacity and reduced the settlement of railway foundation. The optimum length of geogrid reinforcement is about 4B. The effective depth of geogrid placement from the bottom of ballast is about 0.1B-0.2B depended on magnitude of applied load.

• Proceedings of the Korean Geotechical Society Conference
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• 1998.10a
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• pp.305-312
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• 1998

• Journal of Auto-vehicle Safety Association
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• v.12 no.1
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• pp.33-38
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• 2020

Since a diesel vehicle scandal related to the 'A' automobile company was issued in the United States in 2015, many countries have been interested in emission defeat devices. Being embedded in some diesel passenger cars sold in Korea, a defeat device for exhaust gas may have influence on both fuel economy and NOx emissions. In order to examine such effects, we carried out laboratory indoor tests as well as real road driving tests using four models of 'A' automobile company which may employ defeat devices. Those tests were performed observing the test modes of FTP-75, HWFET, and NEDC. Although fuel economy and NOx emissions according to indoor tests comply with the suggested tolerance, the findings in the real road driving tests do not satisfy the tolerance. Along with the results provided in this study, further evaluation may be necessary to investigate the noticeable difference between the indoor and real road tests.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.731-738
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• 2002

Recently, as large constructions on the coast are performed frequently, surface layer stabilization method which Is one of the improvement methods for dredged soft clay has been applied. However, there have been few studies about the surface layer stabilization method. The purpose of this study is to clarify characteristics of ultra-soft marine clay and hardening agent. Also, optimal mixture ratio of hardening agent was verified through the laboratory tests such as statistical analysis and pilot tests. Laboratory tests were performed with proper hardening agent and test soil and standard mixing tables of hardening agent were determined according to ground conditions through statistical analysis. Also, applicability of surface layer stabilization method to field was verified by pilot tests. From the results of the tests, it was found that hardening agent materials such as cement, slag, fly-ash, inorganic salts, arwin, gypsum etc. affect on the appearing compressive strength. It was defined optimal mixture ratio which satisfies the required compressive strength from the statistical analysis. Also, It was compared the effect of ground improvement by cements and hardening agents through the pilot tests. This study will serve as data for design or construction criteria of stabilization of surface layer on ultra-soft marine clay.

• The Journal of Advanced Prosthodontics
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• v.12 no.3
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• pp.157-166
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• 2020

PURPOSE. The aim of this study was to evaluate the clinical performance and reliability of plasma sprayed nanostructured zirconia (NSZ) coating. MATERIALS AND METHODS. This study consisted of three areas of analysis: (1) Mechanical property: surface roughness of NSZ coating and bond strength between NSZ coating and titanium specimens were measured, and the microstructure of bonding interface was also observed by scanning election microscope (SEM). (2) Biocompatibility: hemolysis tests, cell proliferation tests, and rat subcutaneous implant test were conducted to evaluate the biocompatibility of NSZ coating. (3) Mechanical compatibility: fracture and artificial aging tests were performed to measure the mechanical compatibility of NSZ-coated titanium abutments. RESULTS. In the mechanical study, 400 ㎛ thick NSZ coatings had the highest bond strength (71.22 ± 1.02 MPa), and a compact transition layer could be observed. In addition, NSZ coating showed excellent biocompatibility in both hemolysis tests and cell proliferation tests. In subcutaneous implant test, NSZ-coated plates showed similar inflammation elimination and fibrous tissue formation processes with that of titanium specimens. Regarding fatigue tests, all NSZ-coated abutments survived in the five-year fatigue test and showed sufficient fracture strength (407.65-663.7 N) for incisor teeth. CONCLUSION. In this study, the plasmasprayed NSZ-coated titanium abutments presented sufficient fracture strength and biocompatibility, and it was demonstrated that plasma spray was a reliable method to prepare high-quality zirconia coating.

• Korean Journal of Clinical Laboratory Science
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• v.45 no.4
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• pp.149-153
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• 2013

Candidiasis is a fungal infection of the most common causes; generally, opportunistic infections occur often in patients with weakened immune systems. Because of high rates in fungal infection patients and increasing frequency of being isolated from clinical materials, quickly identifying of Candida albicans is critical. By identifying 404 yeast cell strains of referred samples via API 20C kits, NGL and PRO tests and Germ tube (GT) test were conducted and compared. In the 3.0 McFarland yeast cells, 0.1% ${\rho}-nitrophenyl-N-acetyl-{\beta}-D-galactosaminide$ (NGL) and 0.04% ${\small{L}}$-proline ${\beta}$-naphtylamide (PRO) were each put in test tubes and incubated at $35^{\circ}C$ for 15, 30, 60 and 90 minutes. Afterwards, 1 drop of 2% NaOH was applied, and if the color turned yellow; it was positive for NGL test. Afterwards, 1% ${\rho}$-dimethylaminocinnamaldehyde was applied, and if the upper layer turned pink or red, it was positive for PRO test. NGL and PRO tests were conducted for all C. albicans and identified accurately within 30 minutes. In NGL, PRO test, false-positive, negative were not seen, whereas, GT test showed false-positive in 1 strain and false-negative in 3 strains. Therefore, sensitivity and specificity of NGL, PRO tests were 100% and 99.5%, respectively, and positive and negative predictive rate were 99.5% and 100%, respectively. However, GT test sensitivity and specificity were 98.5% and 99.5%, respectively, and positive and negative predictive rates were 99.5% and 98.5%, respectively. In conclusion, NGL, PRO tests are better than GT tests for sensitivity and specificity, therefore, these reliable tests will be useful in clinical laboratories.

• Korean Journal of Clinical Laboratory Science
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• v.53 no.3
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• pp.277-283
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• 2021

The genus Lactococcus is a gram-positive, catalase-negative, non-motile bacterium. It is a facultative anaerobe and can be cultured at 10~40℃. The genus Lactococcus consists of 16 species, of which Lactococcus garvieae and Lactococcus lactis are known to cause disease in humans. This study reports the first case in which L. garvieae was identified in the urine culture of a 74-year-old woman. The patient confirmed the findings of acute urinary tract infection through blood tests, microbial identification tests, antibiotic susceptibility tests, and computed tomography performed at a hospital. The patient was admitted to the nephrology ward and was treated with IV fluids and erythromycin antibiotics and discharged 5 days later. This is the first case in Korea in which L. garvieae was isolated from the urine of a patient with a urinary tract infection and is expected to be useful in treating patients with L. garvieae infection in the future.