• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 1997.11a
• /
• pp.451-455
• /
• 1997

The partial discharge has been blown as the chief breakdown of power equipments. The analysis and the recognition is much difficult because the partial discharge signal is very small and has complex aging pattern. Recently, insulation aging diagnosis based on pattern of phase(Ф), partial discharge magnitude(q), number(n) has been very important. Owing to depreciate the reappearance of aging progress at the electrical tree pattern and to be difficult to analyze visually, the study on partial discharge pattern is suggested to normalizing analysis method of partial discharge signals. This parer is purposed on prediction of life-time measurement of cv-cable, on decision of risk degree with normalization and real-time measurement of partial discharge signals for aging diagnosis of cv-cable. As normalizing the aging signals of electrical tree in cv-cable, it is able to confirm risk degree of insulation material with the distribution of Ф-q-n and recognize the process of aging pattern using neural network.

• Journal of Navigation and Port Research
• /
• v.36 no.4
• /
• pp.279-284
• /
• 2012

This study aims to identify the degree of safety when mariners take their actions in several different situations. We have carried out many experiments to observe mariners' behavior and then measured the safety level based on their actions to avoid dangerous situations of ships collision. One of the most important actions that mariners have to take, either as their daily routine or when they are in a collision situation and then want to avoid that situation is the lookout. In this paper, behaviors on the lookout have been defined as a standard sequence of three steps which are "time of first detection", "time of recognition as risky vessel" and "time of starting avoiding action", and the suitability and applicability of the definition have been shown. And also we propose the risk assessment on ships collision and the recommendation for reducing ships collision at sea. Some analyzing results and the application of the results are reported. By combining these knowledge and some systematic studies, we propose the risk assessment on ships collision and the recommendation for reducing ships collision at sea.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.11 no.2
• /
• pp.237-244
• /
• 2016

There are two destinations to aware the risk of common life. Recognition of the condition of pedestrian's own and the environmental factor awareness both are beneficial for risk awareness. It is good way of advancing the crime prevention effectivity that including IoT technology at the crime prevention research. The purpose of this research is that advanced way of crime prevention with multi-sensor data fusion of the condition of pedestrian and environmental factors. The 3-axis acceleration sensor is available to recognize the gait and the illumination sensor also useful to infer the road state. This research suggest a novel way of assess these factors and the result is the degree of danger.

• Journal of the Society of Naval Architects of Korea
• /
• v.47 no.1
• /
• pp.76-87
• /
• 2010

According to the new rules and regulations (New SOLAS), major safety critical systems are to be designed to be redundant, which is called 'Redundancy Design'. This paper was to quantitatively analyze the degree of influence of the redundancy design applied to major safety critical systems using IMO's FSA(formal Safety Assessment) method. For the purpose of this study, the diesel engine system, which is actually one of major safety critical systems, was dealt with FMEA, FTA and ETA technique. In addition, whether the redundancy was met or not was verified and the degree of safety, or redundancy, was represented in terms of reliability. In conclusion, the safety of propulsion systems is possibly assessed systematically by estimating the risk level in terms of frequency and fatality.

• International Journal of Advanced Culture Technology
• /
• v.3 no.1
• /
• pp.68-77
• /
• 2015

This study was the use of the finite element method in the deep drawing process of a rectangular shell cup. The aim was to analyse the equivalent strain in the workpiece and to find out what happened to the disc blank sheet before the forming by stamping. The rectangular shell cup was $24{\times}30{\times}20$ mm. and made of 2mm.thick SUS 403 and SUS 304 stainless steel. There were 3 types of blank sheets: 1) square sheet 2) 45 degree angled edge cutting sheet 3) circular sheet. It was found out that the drawing up with the use of 3 types of blank sheet made of SUS 304 stainless steel had no risk in the workpiece. For the stamping of the rectangular shell that used a square sheet made of SUS 403 stainless steel, it was found out that there was no risk in the work piece, but with the use of 45 degree angled edge cutting sheet or round sheet, the work piece had a risk to be damaged.

• Journal of Korean Public Health Nursing
• /
• v.26 no.2
• /
• pp.328-340
• /
• 2012

Purpose: This study explored the degree of internet addiction and its influencing factors in lower grade elementary school children in rural areas. Methods: Subjects included 1,137 elementary school children. A structured questionnaire consisting of questions internet addiction, family function and school life satisfaction was used for data collection. Descriptive statistics, ${\chi}^2$-test, ANOVA and Correlation and Regression were performed using a SPSS program. Results: Among the subjects, 85.8% were regular users, 8.1% were potential risk users, and 6.1% were high-risk users. Career of internet use, daily internet access time, the number of conversations per week, the number of times spent eating out and traveling with parents within the last month and activities with friends, and satisfaction on school life differed significantly according to the degree of internet addiction. Finally, among the factors studied, daily internet access time, conversations within family, activities with friends and school life satisfaction in children in early elementary school was 20.7% of the explanatory power of the subjects' degree of internet addiction, collectively. Conclusion: Use of the internet by early elementary school children should be monitored and strategies to promote familial conversations, activities with peers and school life satisfaction should be developed.

• Journal of Pharmacopuncture
• /
• v.27 no.3
• /
• pp.199-210
• /
• 2024

Objectives: Few studies have examined the impact of healthy sleep among general workers on individuals and society. Therefore, the status and risk factors of sleep disturbances among general workers were investigated. In addition, this study assessed the degree to which cold and heat symptoms are associated with sleep disturbances. Methods: A nationwide cross-sectional study was conducted through an online questionnaire focused on sleep disturbances of the general public in 2021. The degree of cold-heat pattern Identification (CHPI) of the general public was also surveyed. Descriptive statistics and multivariate logistic regression were used to derive the study results. Results: Data from 2,822 workers out of 3,900 valid questionnaires were analyzed. Approximately half of the respondents (49.93%) had sleep disturbances. Among the types of work, self-employed, two-shift work, and working more than 53 hours were associated with sleep disturbances. Sleep disturbances were positively associated with six cold and heat symptoms: three cold symptoms (coldness of the abdomen, coldness of body, and pale face) and three heat symptoms (body feverishness, feverishness of the limbs, and drinking cold water). Conclusion: Customized policies to maintain healthy work are needed for self-employed work, two-shift work, and long working hours, which are risk factors for workers' sleep disturbances. In addition, medical personnel can effectively diagnose and treat sleep disturbances considering the worker's cold and heat symptoms.

• Journal of Navigation and Port Research
• /
• v.40 no.5
• /
• pp.257-263
• /
• 2016

Mombasa is the principle port of Kenya, serving inland countries in Eastern and central Africa. Mombasa port has undergone a massive infrastructure upgrade and dredging works with an expectation that more vessels and large post Panamax ships will be able to enter Mombasa port. Therefore, it is vital to carry out a marine traffic risk assessment in order to quantify the degree of navigation safety needed in the Mombasa approach channel and also to evaluate the navigation risk imposed on transit traffic by local ferry traffic. In this paper, a marine traffic risk assessment is carried out using the IWRAP mk2, Environmental Stress (ES) model, and the PARK model. Risk assessment results show that Likoni area has an unacceptable stress/risk ranking at 20.7% by the ES model and 38.89% by the PARK model. The IWRAP mk2 model shows that the crossing area has the highest risk of crossing collision and the area at the entrance to the inner channel has a high risk of grounding. The conclusions derived from this study will provide the basis for proposing the most effective countermeasure to improve navigation safety in the Mombasa approach channel.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2016.05a
• /
• pp.81-84
• /
• 2016

Mombasa is the principle port of Kenya, serving hinter countries in Eastern and central Africa. Mombasa port has undergone a massive infrastructure upgrade and dredging works with an expectation that more vessels and large post Panamax ships will be able to call at Mombasa port. Therefore, it is vital to carry out a marine traffic risk assessment so as to quantify the degree of navigation safety on Mombasa approach channel and also to evaluate navigation risk imposed on transit traffic by local ferry traffic. In this paper marine traffic risk assessment is carried out using IWRAP mk2, Environmental Stress model, and PARK model. Risk assessment results show that Likoni area has unacceptable stress/ risk ranking at 20.7% on ES model and 38.89% by PARK model. IWRAP mk2 model shows that crossing area has the highest risk of crossing collision and the area at the entrance to inner channel has a high risk of grounding. The conclusions derived from this study will provide the basis for proposing the most effective countermeasure so as to improve navigation safety in Mombasa approach channel.

• International Journal of Highway Engineering
• /
• v.14 no.5
• /
• pp.123-132
• /
• 2012

PURPOSES: This study is to investigate the consideration which relates with a disaster from route alignment process and proposed the method it will be able to evaluate a disaster danger fixed quantity. METHODS: Use the landslide disaster probabilistic map of GIS based and in about landslide occurrence of the route alignment at the time of neighboring area after evaluating a risk fixed quantity, it compared LCC expense in about each alternative route. It developed the system it will be able to analyze a LCC and a disaster risk in about the alternative route. In order to verify a risk analytical algorithm and the system which are developed it selected national road 59 lines on the demonstrative route and it analyzed a disaster risk. RESULTS: Demonstrative route not only the disaster risk to be it will be able to compare a disaster risk fixed quantity like the economical efficiency degree in compliance with LCC expense productions it compared and there being the designer will be able to decide the alternative route, it confirmed. CONCLUSIONS: Roads can be designed by considering occurs repeatedly landslides and debris flow caused by disasters in advance and expect to be able to effect that can reduce the overall cost to recover losses caused by the disaster, and temporally loss is expected.