• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.2
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• pp.29-35
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• 2011

The behaviors of combustion-induced internal flows of SRM equipped with fin-slot grain and submerged nozzle are very complex and diverse. Cold air-flow tests for 2D and 3D scale models of SRM have been done in order to specify the visualization method to analyze particular internal flow patterns such as roll-torque inducing flow. Swirl flow induced by asymmetric vortical tubes also has been visualized through employing various light source and recording directions.

• Journal of the Korean Society of Safety
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• v.32 no.5
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• pp.32-40
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• 2017

The current status of Performance-Based Design (PBD) implemented in 4 wide areas (Seoul, Gyeonggi, Incheon and Busan) over the past 5 years was reviewed with regard to the number of PBD implementation and target buildings. Then, detailed status related to fire scenarios, input information for fire simulation, and grid size were analyzed with the pre-review for the PBD. As a result, the domestic PBD was mainly applied to the mixed occupancy. In the fire simulations performed on the identical fire scenario and fire space, the maximum heat release rate (HRR) varied significantly depending on the PBD designer. Various combustibles were also considered for the identical fire source, and their combustion properties also showed considerable uncertainty. In addition, the applicability of accurate input information for predictive models of heat and smoke detectors was examined. Finally, the average grid size for the fire simulation using Fire Dynamics Simulator (FDS) was analyzed, and the improvement of PBD to minimize designer dependency was proposed.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.181-185
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• 2010

The behavior of combustion-induced internal flow of SRM equipped with fin-slot grain and submerged nozzle is very complex and diverse. Cold air-flow test for 2D and 3D scale models of SRM has been done in order to specify the visualization method to analyze particular internal flow patterns such as roll-torque inducing flow. Swirl flow induced by asymmetric vortical tube also has been visualized through employing various light source and recording directions.

• Fire Science and Engineering
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• v.24 no.1
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• pp.111-115
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• 2010

For the development of fire detector equipments that was fused independent type of fire detector and a wireless communication function, this paper adopted a signal processing method of an independent formation fire sensor by a ZigBee communication method, and it was designed that the combinations of fire detector and wireless communications network were enabled. When a fire occurred, output voltage of a fire detector was 0.4 V, the movement pulse width was $600{\mu}s$, and that was confirmed by an experiment. When it has lookout state, LED worked by 30 s cycle and working current is 0.12 mA. When a fire occurred, LED worked by 0.5 s cycle and working current was 7 mA, and through this experiment of power source, Chamber tester, smoke tester,IRED, LED lighting, the propriety of the method that we showed in this paper confirmed.

• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.3
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• pp.31-39
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• 2011

The flowfield in a solid rocket motor was simulated at the wall-injection test model, which has a fin-slot grain and submerged nozzle, and visualized by a smoke-wire. The high speed CCD camera captured the visualized images around the nozzle inlet through the grain center port. The vortical tube structure and circumferential flow patterns at the nozzle throat were visualized. The radial momentum transfer caused by the shear-interactions of slot-outlet flow, fin-base flow and grain port flow from upstream worked as the source of these phenomena.

• International Journal of High-Rise Buildings
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• v.7 no.4
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• pp.265-285
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• 2018

This paper presents a state-of-the-art review on the design, research and education aspects of fire safety engineering (FSE) with a particular concern on high-rise buildings. FSE finds its root after Great Fire of Rome in 64 AD, followed by Great London Fire in 1666. The development of modern FSE is continuously driven by industry revolution, insurance community and government regulations. Now FSE has become a unique engineering discipline and is moving towards performance-based design since 1990s. The performance-based fire safety design (PBFSD) involves identification of fire safety goals, design objectives, establishment of performance criteria, and selection of proper solutions for fire safety. The determination of fire scenarios and design fires have now become major contents for PBFSD. To experience a rapid and positive evolution in design and research consistent with other engineering disciplines, it is important for fire safety engineering as a profession to set up a special educational system to deliver the next-generation fire safety engineers. High-rise buildings have their unique fire safety issues such as rapid fire and smoke spread, extended evacuation time, longer fire duration, mixed occupancies, etc., bringing more difficulties in ensuring life safety and protection of property and environment. A list of recommendations is proposed to improve the fire safety of high-rise buildings. In addition, some source information for specific knowledge and information on FSE is provided in Appendix.

• Journal of Environmental Science International
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• v.20 no.12
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• pp.1647-1661
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• 2011

The Government had devised legislation of Special Act and drew up guidelines for improving air quality in Seoul Metropolitan area. In 2007 local government of Seoul, Incheon and Gyeonggi conducted the results of application policy by reduced air pollutants emission for the first time. Although there was reduction of air pollutant emission in each local government, it was ineffective as expected using air pollution monitoring database. Therefore we worked out a way to prepare modeling input data using the results of enforcement plan. And we simulated surface $NO_2$ and PM10 before and after decrease in air pollutants emission and examine reduction effects of air pollution according to enforcement regulation except other influence, by using MM5-SMOKE-CMAQ system. Each local government calculated the amount of emission reduction under application policy, and we developed to prepare input data so as to apply to SMOKE system using emission reduction of enforcement plan. Distribution factor of emission reduction were classified into detailed source and fuel codes using code mapping method in order to allocate the decreased emission. The code mapping method also included a way to allocate spatial distribution by CAPSS distribution. According to predicted result using the reduction of NOx emission, $NO_2$ concentration was decreased from 19.1 ppb to 18.0 ppb in Seoul. In Gyeonggi and Incheon $NO^2$ concentrations were down to 0.65 ppb and 0.68 ppb after application of enforcement plan. PM10 concentration was reduced from 18.2 ${\mu}g/m^3$ to 17.5 ${\mu}g/m^3$ in Seoul. In Gyeonggi PM10 concentration was down to 0.51 ${\mu}g/m^3$ and in Incheon PM10 concentration was decreased about 0.47 ${\mu}g/m^3$ which was the lower concentration than any other cities.

• Journal of Preventive Medicine and Public Health
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• v.34 no.3
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• pp.183-190
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• 2001

Objective : To estimate the annual economic costs attributable to cigarette smoking in Korea. Methods : The costs were classified as being direct medical and non-medical costs, indirect costs and others. We focused on those costs related that are incurred in the treatment of selected diseases (cardiovascular diseases, respiratory diseases, and cancers), which have been proven to be caused by smoking. In addition to the basic costs of treatment, the additional amount of costs occurred due to smoking was obtained by computing the population attributable risk (PAR%) caused by smoking. To compute the PAR%, relative risks of smoking to the number of outpatient visits, hospitalizations, and the death were estimated using the Cox proportional hazard model, respectively. Our major data source was the 'Korea Medical Insurance Corporation (KMIC) cohort study,' which was composed of a total of 115,682 male and 67,932 female beneficiaries who had complete records of their smoking histories in the year of 1992. Results : The annual costs that could be attributable to smoking were estimated to be in the range of 2,847,500 million Won to 3,959,100 million Won. The maximum estimate of 3,959,100 million Won includes 233,100 million Won for medical costs, 5,100 million Won for transportation costs, 27,600 million Won for care giver's economic costs, 69,100 million Won in productivity loss, 3,435,000 million Won lost because of premature death, 172,100 million Won in costs resulting from passive smoke inhalation and 17,100 million Won for costs that resulted from fires that were caused by careless smoking. Conclusion : Our study confirms that the magnitude of the economic burden of smoking to Korean society is substantial. Therefore, this study provides strong evidence that there is a strong need for a national policy of tobacco control in Korea.

• Korean Journal of Health Education and Promotion
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• v.12 no.2
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• pp.120-138
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• 1995

In order to find smoking status and its related factors for female students, a survey was conducted for 1,045 female students of a women's university in Seoul from 22nd of May to 18th of June, 1995. The results were as follows: 1. Of the 1,045 respondents, 7.4% of them were current smokers and 20.6% of them were ex-smokers. The rate of smoking by the major field of study was 18.5% in art and physical education, 10.6% in liberal art and social science, 1.9% in natural science, and 1.2% in medical science. The rate of smoking by the grade was 4.1% in the freshman, 5.9% in the sophomore, 10.9% in the junior, and 10.0% in the senior grade. 2. 7.2% of respondents experienced first smoking at junior high school, 16.8% at senior high school, 4.1% after high school, and 69.2% at college. 3. The major motivation to start smoking was 'curiosity'(57.9%), 'releasing stress'(21.6%), and 'temptation from friend or senior'(12.0%). 4. The first smoking place was 'entertainment place'(49.6%), 'own room'(20.5%), and 'school '(11.3%). And the first smoking companion was 'friend'(62.3%), 'alone'(19.9%), and 'senior or junior'(5.1%). 5. The average quantity of a daily smoking was 6.16±5.29 cigarettes in current smokers and 31.2% of them had experience to quit smoking at least one or more time. 6. Most of the reasons to quit smoking in ex-smoker were due to 'bad taste '(60.5%), 'health concern'(27.4%) and 'religion'(2.3%). 7. Current smoker and ex-smoker had more positive attitude for the female smoking than nonsmoker. And 76.7% of nonsmokers answered that they would not smoke in the future. 8. Most correspondents(89.8% of nonsmoker, 83.7% of ex-smoker, 80.5% of current smoker) strongly supported the antismoking movement. 9. The major information source in smoking were from 'radio, TV'(51.0%), 'newspaper, magazine'(38.8%) and 'school'(7.7%). 10. The multiple logistic regression analysis showed that the related factors for smoking status were satisfaction of home life, coffee intake, alcohol drinking, sister's smoking, girl friend's smoking, and knowledge about smoking.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.1
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• pp.97-109
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• 2007

Vertical distribution and optical properties of atmospheric aerosols above the Korean peninsula are quite important to estimate effects of aerosol on atmospheric environment and regional radiative forcing. For the first time in Korea, vertical microphysical properties of atmospheric aerosol obtained by inversion algorithm were analyzed based on optical data of multi-wavelength Raman lidar system developed by the Advanced Environmental Monitoring Research Center (ADEMRC), Gwangju Institute Science and Technology (GIST). Data collected on 14 June 2004 at Gwangju ($35.10^{\circ}N,\;126.53^{\circ}E$) and 27 May 2005 at Anmyeon island ($36.32^{\circ}N,\;126.19^{\circ}E$) were used as raw optical data for inversion algorithm. Siberian forest fire smoke and local originated haze were observed above and within the height of PBL, respectively on 14 June 2004 according to NOAA/Hysplit backstrajectory analysis. The inversion of lidar optical data resulted in particle effective radii around $0.31{\sim}0.33{\mu}m$, single scattering albedo between $0.964{\sim}0.977$ at 532 nm in PBL and effective radii of $0.27{\mu}m$ and single scattering albedo between $0.923{\sim}0.924$ above PBL. In the case on 27 May 2005, biomass burning from east China was a main source of aerosol plume. The inversion results of the data on 27 May 2005 were found to be particle effective radii between $0.23{\sim}0.24{\mu}m$, single scattering albedo around $0.924{\sim}0.929$ at 532 nm. Additionally, the inversion values were well matched with those of Sun/sky radiometer in measurement period.