• Proceedings of the KIEE Conference
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• 2001.11a
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• pp.146-148
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• 2001

LIGBT의 캐소드에 전류 제한 능력이 있는 LDMOS를 직렬 연결하여 LIGBT의 전류가 기생 사이리스터가 동작하게 되는 지점까지 증가하는 것을 억제함으로써 기생 사이리스터의 동작으로 인한 LIGBT의 불안정 동작 효과적으로 방지하는 새로운 구조의 LIGBT를 제안한다. 또한 턴-오프 시에 LDMOS의 전류 차단 능력에 의해 전류가 기존의 소자에 비해 빠르게 감소하는 효과로 인해 빠른 스위칭 속도를 얻을 수 있었다.

• Korean Journal of Organic Agriculture
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• v.21 no.4
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• pp.539-554
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• 2013

This study analyses the factors that affect the satisfaction of school meals program. To obtain the data, 54 elementary, middle and high schools in Jeonbuk area were chosen for survey. A ordered probit model analysis is conducted to identify the key explanatory variables that affect the satisfaction of school meals about elementary, middle and high school's students. Also, a ordered probit model is used to calculate marginal effects of several key variables. The study finds that key factors that affect to increase the satisfaction of school meals are rural area schools, elementary school's students, and education for school meals or food nutrition. The satisfaction of school meals in urban and rural school's students are significantly different. Also, the satisfaction of school meals about elementary, middle and high school's students are significantly different. To do this, importance of school meals is to build up the safe agricultural supply system. For safe agricultural supply system, local agricultural products provided in school meals should be supplied based on GAP, HACCP certificated companies such as US FTS(Farm to School) program.

• Safety and Health at Work
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• v.8 no.2
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• pp.151-155
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• 2017

Background: At the entrance of a tunnel, reflection of sunlight from the surrounding environment and a lack of adequate lighting usually cause some vision problems. The purpose of this study was to perform a safety evaluation of lighting on a very long road in Ilam, Iran. Methods: The average luminance was measured using a luminance meter (model S3; Hagner, Solna, Sweden). A camera (model 108, 35-mm single-lens reflex; Yashica, Nagano, Japan) was used to take photographs of the safe stopping distance from the tunnel entrance. Equivalent luminance was determined according to the Holliday polar diagram. Results: Considering the average luminance at the tunnel entrance ($116.7cd/m^2$) and using Adrian's equation, the safe level of lighting at the entrance of the tunnel was determined to be 0.7. Conclusion: A comparison between the results of the safe levels of lighting at the entrance of the tunnel and the De Boer scale showed that the phenomenon of black holes is created at the tunnel entrance. This may lead to a misadaptation of the drivers' eyes to the change in luminance level at the entrance of the tunnel, thereby increasing the risk of road accidents in this zone.

• Journal of the Korea Safety Management & Science
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• v.18 no.3
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• pp.25-31
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• 2016

Occupational Safety and Health Expenses Law in construction industry was enacted in 1988 by the notification of Ministry of Employment and Labor and 22 revisions have been made since. The fact that revisions have been made almost every year since the first enactment shows that Occupational Safety and Health Expenses can effectively prevent construction accidents and the need for revisions to fit the reality has been raised continuously. Despite the construction industry has undergone various internal and external environmental changes, (such as the changes in the safety and health management techniques and the increase in the construction employees' desire for safety) the appropriation standard of Occupational Safety and Health Expenses has been calculated based on the contract price. The construction industry has constantly suggested that the Occupational Safety and Health Expenses be calculated based on the estimated construction expenses since applying the current method doesn't provide enough money to secure the safety. Also because it has become mandatory to hire a health manager since 2015, the lack of Occupational Safety and Health Expenses is expected to get worse. In this study, we will analyze the usage of Occupational Safety and Health Expenses and propose a more practical and realistic change in setting the appropriation standard of Occupational Safety and Health Expenses.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.6
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• pp.623-628
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• 2012

Conventional path planning methods have focused on the generation of an optimal shortest path to the goal. However, this optimal path cannot guarantee safe navigation, because it can often lead to a narrow area. Therefore, we propose a Coulomb's law-based safe path planning method that uses an information grid map. The information grid map includes four types of information: occupied, empty, guide, and dangerous areas. A safe path can be generated away from the dangerous area and close to the guide area by repulsive and attractive forces, respectively. Experiments and simulations show that the proposed method can generate paths inside the safe region and is useful for safe navigation.

• Journal of the Korean Society of Safety
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• v.21 no.5 s.77
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• pp.60-71
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• 2006

In recent years, the most safety studies have been focused on identifying the relationship between safety climate and safe work behavior in accordance with the awareness that prime causes of accidents are organizational, managerial, and human factors rather than pure technical failures across the world. This study focused empirical research aimed at finding out the safety climate factors and examining the relationships of the safety climate and safe work behavior in construction site in Korea, too. A 10 numbers of safety climate factors were adapted from the Mohamed's study(2002) and tested using PLS-GRAPH 3.0 expecting same results as Mohamed' study. And then the relationship between safety climate and safe work behavior was examined. Only two safety climate factors-personal risk appreciation and worker's safety competence-were found and a strong positive relationship between safety climate and safe work behavior was identified in this study. Discussed in details about the results and implications and suggested further studies.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.3
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• pp.428-432
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• 2015

Objectives: The purpose of this study was to research 'Daeri' drivers who work for drunken customers as a substitute driver. This was the first study in Korea to investigate assault and verbal abuse experienced while employed as a 'Daeri' driver. Methods: In this study, we conducted a survey to investigate people who work as 'Daeri' drivers. The survey was performed from September 1 to 7, 2014. The participants were 166 adult men and women who work as full-time 'Daeri' drivers. Results: Participants who experienced physical violence and assault from the customers to the point of disturbing safe driving in a year were 36.1% of total respondents. People who experienced verbal abuse to the point of disturbing safe driving in a year totaled 80.4% of respondents. In addition, there were also qualitative research results. Conclusions: Acts that impede safe driving are a danger to both passengers and drivers. By protecting the safety of 'Daeri' drivers, we will be able to protect the safety of citizens. Therefore, it is necessary to make an effort to protect 'Daeri' drivers from customer violence. Furthermore, it is also necessary to research policy to emplace a legal system that can protect 'Daeri' drivers.

• Imaging Science in Dentistry
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• v.52 no.1
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• pp.67-74
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• 2022

Purpose: To focus on the effects of the presence of mesiodens on adjacent teeth and to investigate the timing of its safe removal. Materials and Methods: Cone-beam computed tomography examinations, obtained at Okayama University Hospital over a three-year period, were inspected. Data were recorded including the number of mesiodens; associated abnormalities; and the relationship with neighboring structures. Depending on multiple factors, the risk of developing complications due to early extraction of a mesiodens was divided into three categories: high, medium, and low risk. Results: A total of 5,958 cone-beam computed tomography exams were obtained, 460 patients aged 3-85 years were diagnosed with a total of 568 mesiodens, 382 (67.3%) of which were discovered in young patients (age <10 years), and 333 (87.2%) of these were associated with abnormalities. Regarding the risk categories, 11 (1.9%) were considered to be in the high-risk, five (0.9%) in the medium-risk and 552 (97.2%) in the low-risk categories. Moreover, eight out of 11 high-risk mesiodens were extracted and no post-operative complications have been seen. Conclusion: As the results showed that no postoperative complications were seen in all the extracted cases of high-risk mesiodens, this indicates the possibility of safe extraction at an early age which could reduce related future complications.

• Quality Improvement in Health Care
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• v.25 no.1
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• pp.52-65
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• 2019

Purpose: Outbreaks resulting from medication injections have recently been on the rise in Korea despite various established guidelines. The objective of this study was to assess the degree to which healthcare professionals are aware of safe injection practice guidelines and to account for the adherence to and the deviation from safe injection guidelines formulated by healthcare providers. Methods: In November 2016, a cross-sectional anonymous questionnaire covering general characteristics of injections, patient safety culture, awareness of safe injection practices, and adherence to and barriers to safe injection guidelines was issued to healthcare providers who administer medication injections or manage and supervise these injections (N=550). Multivariate logistic regression analysis via enter method was performed to define the influencing factors of adherence of safe injection practices. Results: On average, respondents adhere to 17 of the 24 guidelines. Multivariate logistic regression found that those who were more likely to adhere to safe injection guidelines either underwent a patient safety training experience within the last year, provided care in a setting characterized by a highly developed patient safety culture, or were employed as physicians or nurses, as opposed to some other type of care provider. Barriers to safe injection guidelines were attributable to; thoughts of waste to discard leftover medicine, provisions that made adherence cumbersome, a weak culture of compliance, and insufficient amounts of injectable medicine, products, and education. Conclusions: The results of this study indicate that controllable factors like training experience of healthcare providers and patient safety culture were positively associated with adherence to safe injection practices. It was suggested that the training of healthcare providers on safe injection practices be a continuous process to promote patient safety. Additionally, there should be an increased focus on developing and implementing policies to improve patient safety culture from a prevention rather than post-management perspective.

• Journal of the Korean Society of Safety
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• v.38 no.2
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• pp.112-119
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• 2023

This study analyzes the effects of personal lockers, drinking fountains, and all-in-one shutters (hereinafter referred to as "corridor walking obstacles") on evacuation safety to suggest the necessity of operating a more effective educational facility safety certification system. To achieve this purpose, the five-story high school building with the obstacles installed in the corridor has been chosen, and evacuation tests through the Pathfinder Simulation Program have been carried out. When the evacuation exit is designated in the current state, where the students are placed on the 2nd, 3rd, and 4th floors and the corridor walking obstacles are applied as a variable, the required safe egress time (RSET) is 322 seconds. This can lead to dangerous results in the event of a disaster by exceeding the available safe egress time (ASET) standard of 240 seconds by 82 seconds. When students are placed on the 1st, 2nd, and 3rd floors under the same conditions, the RSET is 214.5 seconds, 25.5 seconds lower than the ASET standard, indicating that it is effective in reducing the impact of walking obstacles on evacuation time. The safety management plan for walking obstacles in the corridors is discussed, considering the special characteristics of the school corridors. The results of this study can be used as the necessary data for optimizing evacuation routes in corridors and creating a safe, educational environment.