• Journal of the Korean Institute of Navigation
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• v.20 no.3
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• pp.107-115
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• 1996

With the rapid advance of electronic equipments and the frequent, use of them, the electromagnetic environments including EMC or EMI problems are very complicated. The radiation of electromagnetic waves from electronic equipments has strictly been controlled by the authorities concerned from many years ago. Though it is the most proper to test EMI or EMC in the open area test site, we have used the anechoic chamber in place of the test site because of its various restrictions. To achieve the purpose, in this paper, the performances of a few anechoic chambers according to absorbing materials are analyzed for horizontal and vertical polarizations respectively. Furthermore, the calculated and the measured site attenuations in semi-anechoic chamber made with ferrite grid are compared. The obtained results are to be valuable for designing an anechoic chamber.

• Journal of Pharmacopuncture
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• v.26 no.4
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• pp.348-356
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• 2023

Objectives: Neuralgia-pharmacopuncture (NP) was recently developed as a water-soluble type of pharmacopuncture inspired by CS (care special pain)-pharmacopuncture. I aimed to evaluate the toxic response and approximate lethal dose of when NP when administered intramuscularly to Sprague Dawley rats. Methods: The experimental group was divided into the NP test substance group and the saline control group and administered at a dose of 1.0 mL/animal to the posterior thigh muscles on both sides using a 1 mL syringe; each group consisted of five males and five females. Each rat was monitored for clinical signs and changes in body weight for 14 days after a single intramuscular injection. After completing observation, necropsy findings and localized tolerance at the injection site were assessed via gross necropsy and histopathological examination. Results: No deaths occurred in the NP or control group, regardless of sex. During the observation period, no changes (such as general symptoms, weight change, or visual observation results at the time of autopsy) were judged to be due to the test substance. Histopathological examination showed no changes at the administration site judged to be caused by the test substance in either the male or female test substance administration groups. In addition, mononuclear cell infiltration of the outer membrane of the femoris muscle at the administration site was observed at the same frequency and extent in the control and NP groups, and was judged to be caused by physical stimulation by the injection needle; therefore, it had no toxicological significance. Conclusion: Based on the above results, the approximate lethal dose for a single intramuscular administration of the test substance NP in Sprague-Dawley rats was judged to be > 1.0 mL/animal, and there were no findings that were judged to be due to the test substance at the administration site.

• Journal of Agricultural Extension & Community Development
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• v.22 no.1
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• pp.93-100
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• 2015

This article describes the process involved in usability testing a agricultural information Web site. In addition to determining the goals and requirements for the agricultural information Web site, a user and task analysis was conducted for defining the its user base and the types of tasks which users might be performing at the site. Usability testing methods with close observation and in-depth interviews provided fresh insights about how users are interacting with the agricultural information Web interface as they approach various information seeking tasks. This study uncovered problems related to unclear terminology, improper interface, location for navigational links, need for context sensitive help, built-in redundancy, and clear and consistent navigation.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.147-152
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• 2006

In this study, we examined the applicability of three-dimensional electrical resistivity survey to detect underground cavities of ground subsidence area at the field test site, located at Yongweol-ri, Muan-gun in Korea. Underground cavities are widely present within the limesilicate bedrock overlain by the alluvial deposits in the area of the test site where the ground subsidences have occurred in the past. The limesilicate cavities are mostly filled with groundwater and clays in the test site. Thus, cavities have low electrical resistivity compared to the surrounding host bedrock. The results of the study have shown that the zones of low resistivity correspond to the zones of the cavities identified in the boreholes at the site, and that the three-dimensional electrical resistivity survey used are very effective to detect underground cavities.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.1
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• pp.40-44
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• 2000

The most proper antibiotic must be selected after antimicrobial susceptibility test. If difference in antimicrobial susceptibility was significant between oral sampling sites, it is rationale to use the most susceptible antibiotic agent respond to dental procedure and object of treatment. This study examined sampling site variation from saliva, supragingival plaque and subgingival plaque of 16 children's oral microbes. The cultured bacterial isolates, which were Streptococcus viridans and Neisseria, were examined for 10 antimicribial drugs with the Bauer-Kirby agar disk diffusion method. The used drugs were Penicillin, Ampicillin, Oxacillin, Cephalothin, Imipenem, Gentamicin, Erythromycin, Vancomycin, Ciprofloxacin, Clindamycin. There was no significant difference between three sampling sites for antimicrobial susceptibility test of S. viridans and Neisseria and the sequence of susceptibility was agreed among them. In conclusion, it was suggested that antimicrobial susceptibility test from saliva, supragingival plaque and subgingival plaque of children have no significant sampling site variation.

• Environmental Engineering Research
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• v.7 no.2
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• pp.59-66
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• 2002

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.7 no.2
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• pp.37-42
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• 2011

Dedicated outdoor air(DOA) system which conditions the outdoor air separately is superior to conventional Cooling + reheating system with respect to energy consumption and indoor comfort. Since the sensible and latent load characteristics of indoor and outdoor are different, it is more efficient to treat them separately. In this study, cycle analysis and on-site performance test of DOA system have been conducted. The study shows that DOA requires 50% less equivalent energy than the conventional system. The on-site performance test of a prototype shows that the coefficient of performance(COP) of the DOA system is 37% higher than the conventional system.

• Proceedings of the SAREK Conference
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• 2007.11a
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• pp.346-351
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• 2007

Dedicated outdoor air(DOA) system which conditions the outdoor air separately is superior to conventional cooling+reheating system with respect to energy consumption and indoor comfort. Since the sensible and latent load characteristics of indoor and outdoor are different, it is more efficient to treat them separately. In this study, cycle analysis and on-site performance test of DOA system have been conducted. The study shows that DOA requires 48.8% less equivalent energy that conventional system. The on-site performance test of the prototype shows that the coefficient of performance(COP) of the DOA system is 37.4% higher than the conventional system.

• Corrosion Science and Technology
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• v.2 no.3
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• pp.109-116
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• 2003

It is well known that SSCC (sulfide stress corrosion cracking) is caused by drastic ingression of hydrogen during the service and accumulation of hydrogen near the potential crack initiation site in the material. It is important to characterize the hydrogen trapping behavior to evaluate the service performance of the high strength pipeline steels. In this study. the relationship between the hydrogen trapping behavior and SSCC susceptibility is evaluated in terms of alloy composition, microstructure and carbide behavior. The hydrogen trapping behavior was measured by electrochemical hydrogen permeation test cell (Devanathan cell). The SSCC susceptibility is evaluated by constant extension rate test and constant strain lest method. The hydrogen trapping behavior is affected greatly by microstructure and nature of carbide particles. The fine TiC, and NbC in the matrix of ferritic structure acts as strong irreversible trap sites whereas the bainitic structure acts as reversible trap site. The SSCC susceptibility is closely related to not only the hydrogen trapping behavior but also the loading condition. As the activity of reversible trap site increases, SSCC susceptibility decreases under static loading condition below yield strength, whereas SSCC susceptibility increases under dynamic loading condition or above yield strength. As the activity of irreversible trap site increases. SSCC susceptibility increases regardless of loading condition. It is cased by the mixed effect of dislocation on hydrogen diffusion and trapping behavior.

• Journal of Industrial Technology
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• v.27 no.B
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• pp.59-64
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• 2007

This study introduces an environmental noise evaluation procedure and results for a wind turbine (W/T) system. Test and evaluation are required by the international standard IEC 61400-11 in the aspect of environmental effect. Test and evaluation are performed on U-50 WT model which is first developed by the domestic W/T manufacturer. W/T test model is under operation in Daekwanryung wind test site. An integrated monitoring system in the test site is utilized for the evaluation. With the noise signal, meteorological data and W/T operational data are monitored in real time by the integrated monitoring system using LabVIEW. From the measured noise data, acoustic power level are estimated and compared with those of other similar size WT under the wind speeds required by international standard.