• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.111-116
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• 2004

An experiment was carried out to confirm the validity of time series evaluation of supersonic mixing condition by using catalytic reaction on a platinum wire. Geseous hydrogen was injected parallel to supersonic freestream (M$\infty$ $\approx$ 1.81) from a slit injector, which was located at backward facing step. Time series condition of supersonic mixing was evaluated by using W-type probe which has a platinum wire and reference wire (nickel wire). The evaluation was by simultaneously measuring each electric circuit which kept the temperature of wire constant. Investigations were also conducted for helium, air and no secondary injectant cases to compare with the hydrogen injectant case. The results indicated that it was possible to measure the time series behavior of air and hydrogen supersonic mixing layer or coherent motion of turbulence by using this evaluation.

• Journal of the Korean Society of Safety
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• v.23 no.5
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• pp.97-104
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• 2008

This study was intended to evaluate the permeable performance through a change of reinforcing materials, curing condition, durability evaluation and permeability test, and to select the reinforcing material which could reduce the durability and water tightness from it, as the study for considering how the change of the outside's environment factors that the concrete structure actually contacted with impacted the concrete's durability especially the permeability by referring to such the background of the study. Accordingly, it was judged that evaluating the permeability by considering the severe environment condition where the concrete structure was placed in was more reasonable than measuring the existing permeability coefficient conducted in the sound state for the permeability evaluation of actually-used concrete structure. In this study, it also could be known that the specimen of hybrid fiber reinforced concrete which mixed the long and short steel fiber was the most effective for water tightness enhancement in severe environmental conditions.

• Journal of Korean Society of Rural Planning
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• v.4 no.2
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• pp.70-78
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• 1998

The objective of this study was to enforce systematic evaluation on the present condition and ecosystem of coastal wetland to use frame of environmental indicators, For this, the indicators for evaluation of coastal wetland were established and were applied to the present condition. Then, the application possibility of this evaluation indicators and management method by group of coastal method are presented. These results present the following consideration in case that the ideal management method on the conservation and development of coastal wetlands was proposed. In case of Kang-hwa island which had the good natural environment, the mlnimum development with maintenance of the present state must be driven. In case of Tae-an which had the good natural environment and development potential, the development that was in harmony with the nature must to be driven. In case of Seo-chon which was previously developed region, the various development programs which had the minimum effects on the natural, living and socio $.$ economic environment must to be provided.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.790-795
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• 2004

The characteristics of refrigerator noise recorded in anechoic chamber was investigated in condition of a the real living room and a kitchen. To predict the noise propagation in an apartment unit, room acoustic simulation software was used. It was found that the noise level in the real living room was $4\sim8dB$ higher than in the anechoic chamber. When a noise barrier and absorption materials were used on the rear wall and floor, the noise level reduced up to $3\sim4dB$. In addition, when the subjective evaluation of auralized refrigerator noise was undertaken using headphone, it was revealed that 21dB (A) is the allowable sound pressure level of 95% satisfaction.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.142-160
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• 2003

Most consumers have noted hair damage following coloring treatments. Proper evaluation of hair bleaching products must be performed using quantitative assessments of hair damage, though they are difficult, because of the slight fluctuations in hair composition. In the present study, we utilized a sensitive evaluation method for hair damage and found that the amount of soluble protein fraction extracted from hair under a reducing condition, termed labile protein, dramatically increased after bleaching.(omitted)

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.05a
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• pp.46-51
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• 2008

In this study, evaluation system of the thermal properties of the exothermic agents was investigated. Exothermic agents property evaluation system was developed by metering variation of power supply. Thermal properties of exothermic agents was affected by material mixture condition of exothermic agents, however, it was not affected by temperature. It is possible to make various exothermic agents by means of regulating thermal properties which is based on property evaluation system of exothermic agents.

• Smart Structures and Systems
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• v.20 no.2
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• pp.139-150
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• 2017

The structural strain plays a significant role in structural condition assessment of in-service bridges in terms of structural bearing capacity, structural reliability level and entire safety redundancy. Therefore, it has been one of the most important parameters concerned by researchers and engineers engaged in structural health monitoring (SHM) practices. In this paper, an SHM system instrumented on the Jiubao Bridge located in Hangzhou, China is firstly introduced. This system involves nine subsystems and has been continuously operated for five years since 2012. As part of the SHM system, a total of 166 fiber Bragg grating (FBG) strain sensors are installed on the bridge to measure the dynamic strain responses of key structural components. Based on the strain monitoring data acquired in recent two years, the strain-based structural condition assessment of the Jiubao Bridge is carried out. The wavelet multi-resolution algorithm is applied to separate the temperature effect from the raw strain data. The obtained strain data under the normal traffic and wind condition and under the typhoon condition are examined for structural safety evaluation. The structural condition rating of the bridge in accordance with the AASHTO specification for condition evaluation and load and resistance factor rating of highway bridges is performed by use of the processed strain data in combination with finite element analysis. The analysis framework presented in this study can be used as a reference for facilitating the assessment, inspection and maintenance activities of in-service bridges instrumented with long-term SHM system.

• Bulletin of the Korean Chemical Society
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• v.26 no.3
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• pp.440-446
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• 2005

A method is described for the determination of dibutyltin (DBT) in sediment by isotope dilution using liquid chromatography inductively-coupled plasma/mass spectrometry (LC-ICP/MS). To achieve the highest accuracy and precision, special attentions are paid in optimization and evaluation of overall processes of the analysis including extraction of analytes, characterization of the standards used for calibration and LC-ICP/MS conditions. An approach for characterization of natural abundance DBT standard has been developed by combining inductively-coupled plasma/optical emission spectrometry (ICP/OES) and LC-ICP/MS for the total Sn assay and the analysis of Sn species present as impurities, respectively. An excellent LC condition for separation of organotin species was found, which is suitable for simultaneous DBT and tributyltin (TBT) analysis as well as impurity analysis of DBT standards. Microwave extraction condition was also optimized for high efficiency while preventing species transformation. The present method determines the amount contents of DBT in sediments with expanded uncertainty of less than 5% and its result shows high degree of equivalence with reference values of an international inter-comparison and a certified reference material (CRM) within stated uncertainties.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.1381-1382
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• 2010

• Journal of Pharmaceutical Investigation
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• v.40 no.1
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• pp.63-66
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• 2010

The "Guidance Document for Bioequivalence Study" was revised for adding to bioequivalence studies of controlled-release products after meal(Korea Food & Drug Administration Notification #2008-22, 2008.5.7). The bioequivalence study design for controlled-release products is $2{\times}2$ crossover under fast and fed condition in respect. For studies of controlled-release products under fed study, the same high-fat diet should be taken within 20 minutes in at least a 10-hour fasting state. The drug products should be administered 30 minutes after the meal started. A high-fat(more than 35 percent of total caloric content of the meal) and high-calorie(over 900 calories) meal is recommended as a test meal for fed BE studies.