• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.1053-1056
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• 2007

The acoustical performance of noise reducing devices installed on the top of a noise barrier were tested by small-scale outdoor tests. Noise measurements before and after installation of the devices were carried out using sound intensity methods. It is well known that the sound intensity method can specify the strength and directivity of sound, and it is convenient to consider the feature of sound around a noise barrier. The noise reduction effect of each edge device was evaluated using the difference between the input and output sound power levels calculated from sound intensities. It was investigated that each device had different efficiency in the shadow zone, while there was no significant difference between edge devices in the illuminated zone.

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2007.05a
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• pp.173-173
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• 2007

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2007.05a
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• pp.174-174
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• 2007

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.309-312
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• 2009

The various hazards should be eliminated before operations for the successful launches or tests. Using the contaminated propellants is one of the causes for the launch and test failures. Especially, the systems using liquid oxygen as an oxidizer have risks about fires and explosions not be forecasted if they are contaminated by oil, water and mechanical impurities. The procedure for the quality control of the liquid oxygen and the liquid oxygen filling system and the lessons learned from the first launch preparation with the system are introduced on this paper.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.246-249
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• 2009

Test and launch facilities which use oxygen as the propellant of a launch vehicle have hazards of fire and explosion by the leakage of oxygen. Also, the personnel operating the facilities, which use the high-pressured gases like nitrogen and helium in the closed room, is exposed to the hazard of death from suffocation. Consequently, we should keep out of the hazards and the accidents by monitoring the contents of oxygen in the air. The method and the system construction for monitoring oxygen contents in the air and the results from its application to Naro space center are described on this paper.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.5
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• pp.432-441
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• 2006

2D fluorescence sensors produce a great deal of spectral data during fermentation processes, which can be analyzed using a variety of statistical techniques. Principal component analysis (PCA) and a self-organizing map (SOM) were used to analyze these 2D fluorescence spectra and to extract useful information from them. PCA resulted in scores and loadings that were visualized in the score-loading plots and used to monitor various fermentation processes with recombinant Escherichia coli and Saccharomyces cerevisiae. The SOM was found to be a useful and interpretative method of classifying the entire gamut of 2D fluorescence spectra and of selecting some significant combinations of excitation and emission wavelengths. The results, including the normalized weights and variances, indicated that the SOM network is capable of being used to interpret the fermentation processes monitored by a 2D fluorescence sensor.

• Journal of the Korean Society of Combustion
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• v.5 no.1
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• pp.43-53
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• 2000

Experimental studies on determination of the supply leading time of propellants to combustion chamber have been made to stably and efficiently guarantee the ignition process with liquid rocket engine. The propellant used is a Jet A-1 as fuel and a liquid oxygen as oxidizer. Unlike impinging FOOF type of injectors are arranged radially and the designed O/F ratio is 2.34. The present experiment program also includes the stability on the quadlet type of ignitor using the triethylalumimum as an ignition source and injector life tests. Experimental results clarifies that the propellant supply through LOx leading to combustion chamber is proper for stable ignition and combustion processes based on the fuel and oxidizer manifold pressures, combustion chamber pressure, and the variation of flame length from the nozzle exit with lapse time, and shows that the leading supply time of propellants affects the engine performance little. The effect of positioning cooling holes is remarkable to protect the injector face.

• Biomolecules & Therapeutics
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• v.19 no.1
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• pp.97-101
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• 2011

Cirsium japonicum var. ussuriense is known to have a variety of biological activities, including anti-inflammatory, analgesic activity and antipyretic activity. In this study we investigated the role of polyacetylene compound, 1-Heptadecene-11, 13-diyne-8, 9, 10-triol (PA) from the root of Cirsium japonicum var. ussuriense as an immune-modulator. PA was evaluated as inhibitors of some macrophage functions involved in the inflammatory process. We tested the effect of PA on the production of pro-inflammatory cytokines, interleukin-1beta (IL-$1{\beta}$) and tumor necrosis factor-alpha (TNF-$\alpha$), and nitric oxide (NO) in murine macrophage cell line, RAW264.7. There was no effect on cytokine production of macrophages by PA itself. However, PA inhibited lipopolysaccharide (LPS)-induced IL-$1{\beta}$ and TNF-$\alpha$ production by macrophages at a dose dependent manner. PA also suppressed the NO production of macrophages by LPS. LPS-induced NF-${\kappa}B$ activity was decreased by treatment of PA. Therefore, these results suggest that PA has anti-inflammatory effect by inhibiting the NF-${\kappa}B$ activation.

• Journal of Preventive Medicine and Public Health
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• v.36 no.2
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• pp.108-116
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• 2003

Objective : To determine the relationships between customer's attitude, the subjective norm and the intention to use hospital-based health promotion services. Methods : This study was based on the theory of reasoned action, suggested by Fishbein and Ajzen. The subjects of this study were 501 residents of Seoul, Bun-dang, Il-san and Pyung-chon city, under 65 years, who were stratified by sex and age. A covariance structural analysis was used to identify the structural relationships between attitude towards health promotion programs or services, their subjective norm and their intention to use the aforementioned services. Results : The subjective norm for using the health promotion programs or services provided by hospitals was a significant predictor of the intention to use, but the attitude towards the services was not significant Conclusions : Our results suggest that a customer's reference group affects their use of the hospital-based health promotion services. Because the subjects of this study were restricted to specific urban areas, there are limitations to generalizing the study results. Despite the limitations of these results, they can serve as baseline information for the understanding of consumers behavior toward hospital-based health promotion services.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.39 no.4
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• pp.378-384
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• 2011

During the flight test of KSLV-I, various sensors are installed in the launch pad and the flame deflector to measure the flame characteristics and their influences on the launch complex when a launch vehicle lifts off. Parameter Measurement System is responsible for acquiring the above flight test data. The measurement methodology such as the configuration of measurement system, sensor locations and data acquisition procedures are presented. And this paper compares and explains the characteristics of data sets measured during two flight tests.