• International Journal of Fluid Machinery and Systems
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• v.6 no.3
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• pp.160-169
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• 2013

Two-stage turbocharging is an important way to raise engine power density, to realize energy saving and emission reducing. At present, turbine matching of two-stage turbocharger is based on MAP of turbine. The matching method does not take the effect of turbines' interaction into consideration, assuming that flow at high pressure turbine outlet and low pressure turbine inlet is uniform. Actually, there is swirl flow at outlet of high pressure turbine, and the swirl flow will influence performance of low pressure turbine which influencing performance of engine further. Three-dimension models of turbines with two-stage turbocharger were built in this paper. Based on the turbine models, mechanism of swirl flow at high pressure turbine outlet influencing low pressure turbine performance was studied and a two-stage radial counter-rotation turbine system was raised. Mechanisms of the influence of counter-rotation turbine system acting on low-pressure turbine were studied using simulation method. The research result proved that in condition of small turbine flow rate corresponding to engine low-speed working condition, counter-rotation turbine system can effectively decrease the influence of swirl flow at high pressure turbine outlet imposing on low pressure turbine and increases efficiency of the low-pressure turbine, furthermore increases the low-speed performance of the engine.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2008.04a
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• pp.253-258
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• 2008

우리나라에서 원자력 시설의 안전 확보를 위한 현장 규제는 원전 부지내에 설치되어 운용되고 있는 주재관실과 방사능 재난 발생에 대응하기 위한 현장방사능방재지휘센터 등으로 분산되어 있다. 원유 고유가, 에너지 안보, 및 기후 변화 협약 등에 대한 대응책으로, 신규 원자력 시설의 건설이 진행 중에 있으며, 이에 따라 원자력 규제 대상이 증가하고 있다. 지역주민이 신뢰하는 원자력 시설의 안전 규제의 필요성에 따라 현장 규제의 업무량도 증가하고 현장 규제 요건도 강화되고 있는 추세이다. 분산되어 있는 원자력 안전규제 시스템을 통합적인 체계로 전환하기 위한 방안들 가운데, 이 연구에서는 규제의 효율성/효과성을 향상시키기 위해 원자력 안전 지역사무소의 설치가 고려되었다. 이 연구의 주요 목적은 시스템 다이내믹스 기법을 활용한 지역사무소 설치의 타당성 모델을 제시하는 것이다. 이 SD 모델을 통해 지역사무소 설치가 규제 효과성을 포함한 다른 변수들에 미치는 영향을 전체론적 (holistic) 관점에서 평가할 수 있다. 이 SD 모델에서 이해관계자 (예: 중앙행정기관, 규제기관, 지방자지단체, NGO, 국민 등) 각각의 우선적인 목표는 갈등적 다중목표가 된다. 이러한 다중목표는 원자력 안전 규제의 의사결정 단계에서 거버넌스(governance) 체제 (예: 규제 기관, 사업자, 지역주민 등이 참여하는 체제)의 구축, 원자력 관련 민원 해결을 통해 성취될 수 있다. 시스템 다이내믹스 접근법의 주요 변수 정의 단계에서는 다양한 관점의 상호영향을 고려하면서 지역사무소 설치에 필요한 기본 개념이 도출되었다. 시스템 다이내믹스 접근법의 모델링 단계에서는 이들 기본 개념에서부터 지역사무소 설치 타당성 정책의 인과 지도(causal map)가 작성되었다. 이러한 인과 지도들로부터 지역사무소의 설치 타당성으로 이끄는 다양한 자기-강화 (self-reinforcing) 루프들이 발견되었다.

• Journal of Korean Society for Quality Management
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• v.41 no.4
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• pp.623-635
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• 2013

Purpose: The recent major recalls of hazardous products caused consumer product safety acts to be strengthen worldwide. Although the recall system of hazardous products in Korea has been operating based on Framework Act on Product Safety since 2011, the evaluation of product risk has been relied on not the results of objective incident data but the results of illegal product investigations. The purpose of this paper is to propose a product risk assessment model for Korea using injury data. Methods: The authors derived Korea's risk assessment method by analysing the advantages and disadvantages of the most widely used models in advanced countries such as EU's RAPEX RAG and Janpan's R-MAP. In this study, the level of relative frequency and severity of injury are determined based on the objective incident data and the length of hospitalization respectively. In addition, the injury data occurred during 2011 is applied to the proposed risk assessment model for case study. Results: The data analysed in this paper can be classified as high risk, medium risk, low risk, acceptable risk, and safe products through the matrix f rom the combination of the relative frequency and the severity derived. Conclusion: The proposed risk assessment model in this study has advantage obtaining reliable objective results because it uses actual injury data and redeems the drawbacks of the existing models used in advanced countries. Furthermore, because the proposed model shows the high risk products among many, it is expected to be useful especially for customs whose main job is inspecting the imported goods and the government when selecting the target product groups for safety investigation.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.9
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• pp.1156-1162
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• 2014

To prevent the Sewol incident again, by which the victims are 294 dead and still 10 missing, this study analyzed the change of safety consciousness of passengers onboard ship comparatively before and after the Sewol incident. The survey had performed 2 times at Jeju coastal cruise terminal at February 2014 and May 2014, and effective respondents were 394 and 401, respectively. After the Sewol incidents, the answers' ratio that they would follow the routes that the crews show and they would follow the crews' evacuation guides are decreased 24.5% and 18.5%, respectively. This means that the reliability on the crew members were decreased. Although 77.6% passengers responded that they felt nervousness onboard ship, 60% did not take safety lesson(s) and 45% did not know how to wear a life jacket. And also over 50% did not check the evacuation route map and the location of lifeboat, respectively. Meanwhile, 86.9% respondents answered the system of safey lesson should be changed, which has normally done by TV set.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.4
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• pp.691-702
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• 2015

This study examined the levels of risk perception of food risk elements by adopting a psychometric paradigm and analyzed factors affecting concerns about food risk elements to obtain basic materials for food safety policy. The data were collected from 296 housewives in Daegu, Korea, by a self-administered questionnaire. Frequency distributions, Pearson's correlation coefficient analysis, factor analysis, Cronbach's ${alpha}$, and multiple regression analyses were conducted by SPSS 21.0. The mean level of concern for food safety was 3.75/5.00 points, and the mean percentage of correct answers about heavy metal contamination was highest among food risk elements. The respondents perceived radioactive contaminated foods, GM foods, and endocrine disruptors as a new, delayed, scientifically unknown, involuntary, serious, and uncontrollable risk in risk perception. According to the result of factor analysis for risk perception, two factors such as non-controllability and dread were categorized. In the risk perception map, radioactive contaminated foods and GM foods were considered as an uncontrollable and dreaded risk, heavy metal contamination, endocrine disruptors, and pesticide residues as a controllable and dreaded risk, and foodborne illness and food additives as a controllable and less dreaded risk. On the other hand, the levels of concerns about food risk elements were higher in order of radioactive contaminated foods, GM foods, and endocrine disruptors. The results of multiple regression analysis showed that age, concern for food safety, percentage of correct answers about food risk elements, non-controllability, and dread influenced the concerns about food risk elements. These results imply that food safety policies should consider differences in consumer's risk perception of food risk elements.

• Journal of the Korean Institute of Gas
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• v.25 no.5
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• pp.19-29
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• 2021

Due to the climate changing, the world's countries are tightening regulations on CO2 and air pollutants emission to solve them. In addition, eco friendly vehicles is increasing to replace automobiles in internal combustion engine. Recently, the government is supporting the expansion of hydrogen refueling infrastructure and localization of core equipment in refueling facilities according to the hydrogen economy road map. In this study, design of the Excess flow limiting device in FCEV cylinder valve using by finite element analysis and performed performance tests on prototype. Major test results as hydrostatic strength, continued operation, operation, pressure impulse, leakage showed that the excess flow limiting device meets the performance requirements according to ISO 12619-2 and ISO 12619-11.

• Journal of Korean Society of Disaster and Security
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• v.6 no.3
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• pp.49-57
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• 2013

This paper is to show the long-term roadmap by analyzing the development trend for the safety technology of facility disaster in the country and abroad, and it is designed to plan the long term and roadmap in response to change the disaster environment. Recently in the country, it is increasing the needs of the long term roadmap design of the facility disaster research development in the facility disaster, by the repidly of the social and the living and the related governments response's changing. The U.S. is going to develop the disaster responding research by planning the its master plans, including the NRF (National Responing Framwork), the NIMS (National Incident Management System), and its sinarios etc.. Japan is going to develop the research planning in the annual report of the disaster prevention, and we going to do the study projects about the facility disaster area with the NEMA (National Emergency Management Agency) and NDMI (National Disaster Management Institute). This paper is showed to design the long term roadmap of the facility disaster's study development, and to minimize the damage of the man and his property, and to set the study development system of the national facility disaster, and furthering to make the resilient planning in changing of the facility disaster's environment.

• Spatial Information Research
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• v.22 no.3
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• pp.79-87
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• 2014

In order to foster rapid disaster response and public life protection, National Emergency Management Agency has been trying to spread 'Emergency Rescue Standard System' on a national scale since 2006. The agency has also intensified management of firefighter's safety on disaster site by implementing danger predication training, specialized training and education and safety procedure check as a part of safety management officer duties. Nevertheless, there are limitations for effective fire fighting steps, such as damage spreading and life damage due to unawareness of illegal converted structure, structure transformation by high temperature and nearby hazardous material storage as well as extemporary situation handling endangered firefighter's life. In order to eliminate these limitations there is a need for an effort and technology application to minimize human errors such as inaccurate situational awareness, wrong decision built on experience and judgment of field commander and firefighters. The purpose of this study is to propose a new disaster response model which is applied with geospatial information. we executed spatial contextual awareness map analysis using fire-fighting vulnerable zone model to propose the new disaster response model and also examined a case study for Dalseo-gu in Daegu Metropolitan City. Finally, we also suggested operational concept of new proposed model on a national scale.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.7 no.1
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• pp.29-37
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• 2013

The purpose of this study is to suggest the potential domestic and international market conditions vehicles for people with disabilities through a review of the literature and internet resources, and to propose a road map developing South Korean vehicles for people with disabilities taking into consideration the current state of domestic and international technology and the usage of the vehicles for people with disabilities depending on the type of disability. The results of the study are as follows: First, vehicles for people with disabilities safety standards of South Korea do not meet the safety standards of developed countries and the technology of development related vehicles for people with disabilities is not as advanced as that of developed countries. Vehicles for people with disabilities installation methods, specifications, features and safety standards should be designed to be more similar to those of Japan and the United States. Second, vehicle modifications for people with disabilities will become more common as measures directed at promoting the welfare of people with disabilities, such as travel and transportation measures, employment opportunities, education, and funding for vehicle modifications, are implemented along with laws, such as The Americans with Disabilities Act, The British Disability Discrimination Act, and Japan's barrier-free transport law, that protect people with disabilities generally. Third, through a comparative analysis of domestic and international market conditions and demands of people with disabilities in vehicle modifications, important things to pay attention by purchasing a modified vehicle for people with disabilities are the employment rate for people with disabilities and monthly income. To enable this, government agencies and industry bodies should work together through the revision of the current Disability Welfare Act or the enactment of the special law for guiding principles of Disability Welfare Act. Through the future changes in vehicles for people with disabilities-related system or society of South Korean, the annual demand of the vehicles is expected to be more than 10,000.

• Journal of the Korean Association of Geographic Information Studies
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• v.25 no.1
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• pp.56-76
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• 2022

This study shared with community mapping participants spatial analysis information, collected using smart devices, to give them an opportunity to objectively review their opinions. The study examined the impact of sharing such spatial information on residents' decision-making and perceptions. Yeongju-dong in Jung-gu district of Busan Metropolitan City, South Korea was selected for the case study; community mapping was carried out in Yeongju-dong to identify hazardous areas to improve pedestrian safety of primary school students. The community mapping participants drew a preliminary hazard map based on their experience and perception. Then, they drew a second hazard map after being given spatial information on pedestrian safety installations and pedestrian flow collected with smart devices including drones and sensors. Numerous changes in ranking across various sections occurred when the two maps were compared. There was a climb in the ranking of areas where the pedestrian flow was higher and lacked safety installations based on objective measurements over the perceptions of the participating people. Furthermore, according to a survey conducted among the participants, the provision of spatial analysis information using smart devices during community mapping process not only helped them recognize local community problems, but also raised their expectations that their submitted opinions would be reflected in policies. Moreover, the participants demonstrated increased self-confidence and faith in themselves as they were able to have more trust in the outcome they created.