• International Journal of Aeronautical and Space Sciences
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• v.8 no.2
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• pp.126-131
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• 2007

In this paper, Monte Carlo Simulation (MCS) method was used as an uncertainty assessment tool for air flow, net thrust measurement. Uuncertainty sources of the net thrust measurement were analyzed, and the probability distribution characteristics of each source were discussed. Detailed MCS methodology was described including the effect of the number of simulation. Compared to the conventional sensitivity coefficient method, the MCS method has advantage in the uncertainty assessment. The MCS is comparatively simple, convenient and accurate, especially for complex or nonlinear measurement modeling equations. The uncertainty assessment result by MCS was compared with that of the conventional sensitivity coefficient method, and each method gave different result. The uncertainties in the net thrust measurement by the MCS and the conventional sensitivity coefficient method were 0.906% and 1.209%, respectively. It was concluded that the first order Taylor expansion in the conventional sensitivity coefficient method and the nonlinearity of model equation caused the difference. It was noted that the uncertainty assessment method should be selected carefully according to the mathematical characteristics of the model equation of the measurement.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.2
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• pp.147-153
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• 2013

To prevent paralytic shellfish poisoning (PSP) due to the consumption of shellfish contaminated with PSP toxins, the quantitative analysis of these toxins is very crucial. The AOAC International mouse bioassay (MBA) has been used widely for the routine monitoring of PSP toxins for more than 50 years. However, this method has low sensitivity and high limit of quantification (LOQ) and interferences from other components in the extract, and it cannot determine toxic profiles. Ethical problems also exist with the continued use of this live mouse assay. To establish an alternative method to the MBA used for PSP toxins analysis, we attempted to optimize the analysis conditions of a precolumn high-performance liquid chromatography (HPLC) oxidation method and succeeded in validating its accuracy and precision in quantifying PSP toxins. A clear peak and the isolation of PSP toxins were obtained by injecting the working standards of Certified Reference Materials using HPLC. The LOQ of the precolumn HPLC oxidation method for PSP toxins was about $0.1002{\mu}g/g$, which represented an approximately fourfold improvement in detection capability versus the AOAC MBA. The intra-accuracy and precision for PSP toxins in oysters were 77.0-103.3% and 2.0-5.7%, respectively, while the respective inter-accuracy and precision were 77.3-100.7% and 2.4-6.0%. The mean recoveries of PSP toxins from oysters were 75.2-112.1%. The results of a comparison study showed good correlation between the results of the precolumn HPLC oxidation method and those of MBA, with a correlation factor of 0.9291 for mussels. The precolumn HPLC oxidation method may be used as an alternative to, or supplementary method with, MBA to monitor the occurrence of PSP toxins and to analyze the profiles of these toxins in shellfish.

• The Journal of Korean Medical History
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• v.18 no.1
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• pp.89-101
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• 2005

Obejectives : This survey was accomplished to find out how Korean medical doctors think that the recognition regarding the Korean acupuncture method and research direction Methods : The survey questions were developed by the consensus from the professors who major in acupuncture and moxibustion. The questionnaire was given the 2731 Korean medical doctors at the mending education site; In addition, it was given to 793 doctors working at the 105 Korean medical hospitals listed on the National Korean Medical Hospital Associations Address book by postal mail; and also it was given to the 142 public health care Korean medical doctors who attended the conference for the municipal and provincial representatives of the public health service Korean medical doctors. Total of 1277 questionnaires were retrieved out of the 3666 subjects. Results : 1. Eleven hundred eighth seven out of 1277 Korean medical doctors think motion and bone and joint disease which has an effect in acupuncture treatment(92.9%) 2. Nine hundred fourteen out of 1277 Korean medical doctors used "Body acupuncture method"(71.5%) and 902 out of 1277 Korean medical doctors think of the korean acupuncture method which is "Sa Am acupuncture method"(70.6%) 3. Eight hundred forty out of 1277 Korean medical doctors want verification which leads a clinical research to know that acupuncturist have acupuncture and moxibustion treatment(65.7%). Conclusion : Korean medical doctors think motion and bone and joint disease which has an effect in acupuncture treatment Korean medical doctors most used "Body acupuncture method" but think of the korean acupuncture method which is "Sa Am acupuncture method". Korean medical doctors want verification which leads a clinical research to know that acupuncturist have acupuncture and moxibustion treatment.

• 한국초전도학회:학술대회논문집
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• v.10
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• pp.276-279
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• 2000

When high temperature superconducting tapes is fabricated using the PIT (Powder In Tube) method, the length of HTS tapes is increased more than 500 ${\sim}$ 1,000 times of initial powder packed billet. On mechanical processing, heterogeneous properties between the ceramic superconducting core and Ag/Ag alloy sheath occur the non-uniformity deformation as like sausaging that deteriorate the critical current properties of HTS tapes. In this study, we investigated the workability of Bi-2223/Ag/Ag alloy sheath tapes fabricated by the PIT method involving a number of different mechanical processes, multi drawing and rolling. In order to obtain the high critical current density and high uniformity of Bi-2223/Ag sheath tapes, the influences of powder packing density, drawing die angle and rolling parameters were studied. We found that the roll diameter is an important variable in the rolling process, as critical current of tapes rolled using 250 mm rolls was higher than that using 150 mm rolls.

• Journal of Korean Society on Water Environment
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• v.34 no.5
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• pp.462-469
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• 2018

There are differences in method and cycle of flow rate survey depending on purpose of the operating department. To verify and use results of flow data according to the purpose, flow data of the directly measured and tele monitoring system were compared to verify validity. Flow measurement in the Ministry of Environment is aimed at setting up a standard flow of target water quality for water quality management and securing flow data of low and normal water level seasons for water quality evaluation. In this study, correlation analysis result ($R^2$) of same time zone data by direct measurement and tele monitoring system (TMS) at Seombon D point, a unit watershed of Seomjin river, for six years ('10 ~ '15) according to implementation of Total Daily Maximum Load (TDML) was wading 0.716, boating 0.962 and on bridge 0.943, and effectiveness of measurement method was verified by characteristics of flow duration as a season of dry and low-water; normal and high water are appropriate for wading, boating, and on bridge respectively. Results revealed it is reasonable to use directly measured results using the wading and boating method for low water level and dry seasons, and TMS data for rainy seasons. It can be used important data for future policy decisions.

• Herbal Formula Science
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• v.19 no.1
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• pp.175-182
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• 2011

Objectives : This study was performed to compare the differences between decoctions extracted by different extraction method and extraction time. Methods : Decoctions were prepared with pressed or non-pressed extraction conditions for 60, 120 and 180min. The yields of extracts, sugar contents, hydrogen ion concentrations(pH), the contents of reference compounds in Yukmijihwang-tang(Liuweidihuang-tang) were investigated. Results : The yields and the dissolved solid content containing sugar content of decoctions were more in pressed extraction method than unpressed extraction method, and they tended to be increased as extraction time increased. The pH values of decoctions methods did not show significant differences between pressed and unpressed extraction methods or extraction times. Most of reference compounds showed higher contents in pressed extraction method than unpressed extraction method and their contents were augmented according to increase of extraction time. The content of paeonol was decreased when extracted in more than 120min with pressed extraction method and tended to be decreased as extraction time increased in unpressed extraction method. Conclusions : The pressed extraction with long extraction time could be useful for decoction of Yukmijihwang-tang(Liuweidihuang-tang). However, another ingredients possible to decrease in such condition need to be considered to determine suitable extraction condition.

• Journal of Sasang Constitutional Medicine
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• v.22 no.3
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• pp.67-74
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• 2010

1. Objectives: The research papers published by researchers in other fields except Oriental medicine were analyzed to study the research trends and characteristic of Sasang Constitutional medicine. 2. Methods: Systematic searches were performed on KISS, RISS, KISTI and DBPIA and finally 123 papers were selected. The publication year, research field of the first author, title's characteristic, research topic and the classification method of Sasang Constitution were investigated. 3. Results and conclusions: 1) In the analysis of publication year, the number of studies on Sasang Constitution has increased dramatically since 2000. 2) In the analysis of the first author's research field, physical training, nursing, engineering and food and nutrition were the majority. 3) In the analysis of the research topic, the classification method of Sasang Constitution was the majority. 4) In the analysis of the classification method of Sasang Constitution, QSCC II was the most popular method accounted for 68% and interview by specialist of Sasang Constitutional medicine accounted for 42%.

• Journal of Korean Society on Water Environment
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• v.33 no.2
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• pp.181-186
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• 2017

This paper aimed to evaluate the results of alternative acute toxicity test on 83 wastewater samples. Each sample was tested by traditional method (using laboratory cultured D. magna as a test organism) and alternative method (using Toxikit which can be purchased from a specialized company). The relationship between Lab. culture toxicity and Toxkits toxicity indicated good relation ($r^2=0.84$, p<0.01, n = 83). Number of samples which showed a small difference of lower than 0.5 between two test methods were 52 and they account for 63 percent of collected samples. In addition, these 52 samples had a lower average toxicity of TU 0.5 (Lab. culture method) and TU 0.45 (Toxkits method). Whereas samples which indicated big difference of test results between two methods, had a tendency to show higher toxicity. From these results, alternative toxicity test method could be applied to the official test method, if samples would have a lower toxicity less than TU 2. Also, Toxikit standard toxicant test results indicated $EC_{50}$ values between 0.93 and 1.68 mg/L and these results were considered as valid for quality control standard.

• Journal of Environmental Science International
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• v.26 no.4
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• pp.433-445
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• 2017

In recent years, the United States has used the Load Duration Curve (LDC) method to identify water pollution problems, considering the size of the pollutant load in the entire stream flow condition to effectively evaluate Total Maximum Daily Loads (TMDLs). A study on the improvement of the target water quality evaluation method was carried out by comparing evaluations of two consecutive years of water quality and LDC data for 41 unit watersheds (14 main streams and 27 tributaries). As a result, the achievement rate of the target water quality evaluation method, according to current regulations, was 68-93%, and that by the LDC method was 82-93%. Evaluating the target water quality using the LDC method results in a reduction in the administrative burden and the total amount of planning as compared to the current method.

• Journal of Radiation Protection and Research
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• v.41 no.4
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• pp.384-388
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• 2016

Background: For a verification of newly-developed neutron absorbers, one of guidelines on the qualification and acceptance of neutron absorbers is the neutron attenuation test. However, this approach can cause a problem for the qualifications that it cannot distinguish how the neutron attenuates from materials. Materials and Methods: In this study, an estimation method of neutron absorption performances for materials is proposed to detect both direct penetration and back-scattering neutrons. For the verification of the proposed method, MCNP simulations with the experimental system designed in this study were pursued using the polyethylene, iron, normal glass and the vitrified form. Results and Discussion: The results show that it can easily test neutron absorption ability using single absorber model. Also, from simulation results of single absorber and double absorbers model, it is verified that the proposed method can evaluate not only the direct thermal neutrons passing through materials, but also the scattered neutrons reflected to the materials. Therefore, the neutron absorption performances can be accurately estimated using the proposed method comparing with the conventional neutron attenuation test. Conclusion: It is expected that the proposed method can contribute to increase the reliability of the performance of neutron absorbers.