• Title/Summary/Keyword: Safe life

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An Accelerated Life Test of LED Lights for Aviation Taxiway (항공유도로등화용 LED 광원의 가속수명시험)

  • Min, Kyong-Chan;Yun, Yang-Gi;Kim, Myung-Soo
    • Journal of Applied Reliability
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    • v.11 no.2
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    • pp.127-140
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    • 2011
  • This paper presents an accelerated life test of aviation taxiway lights installed in the airport to help safe navigation of airplanes at night or in bad weather. Recently halogen lamps of taxiway lights are replaced by LED ones and their reliability needs yet to be verified. Thus, effective test conditions are designed reflecting the failure modes and mechanisms from the previous studies on LED, which include the accelerated degradation process. The test is performed under the temperature $70^{\circ}C$ and $90^{\circ}C$ for two types of LED lights, taxiway center line lights(TCLL) and taxiway edge lights (TEDL). The failure time data were analyzed using lognormal distribution and Arrhenius model to find the life-stress relationship, acceleration factor and life characteristics under the normal condition temperature $30^{\circ}C$.

Analysis to be used for the Life Cycle Costs calculation of rolling stocks for EMU (EMU 철도차량의 LCC(Life Cycle Cost)분석)

  • Park, Su-Myung
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.177-183
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    • 2009
  • This paper deals with the topical problems of the Life Cycle Costs in connection with the rolling stocks. the LCC philosophy has already entered the third decade. this philosophy contributed towards the new relationship's comprehension between railway vehicle producers' and railway vehicle users' sphere. this leads together to the technical-economical solution convenient for the both sides. In the point of manufacturer, It is said that low operational costs could be reached using a well-designed and structured maintenance program. this is due to the proper technical analysis of critical components that leads to low costs of maintenance and a superior reliability without increasing the capital investment. but, This paper presents both topical experiences with the LCC models for the railways vehicles and also procedures during Life Cycle Costs calculations. In conclusion I want to introduce how to calculate LCC & what kinds of softwares are used based on VVVF EMU vehicle

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Design and RAMS Evaluation of embedded AVTMR System with Fail-safe Output Voter (고장 안전 특성을 가지는 내장형 AVTMR 시스템의 설계 및 RAMS 평가)

  • Kim Hyunki;Lee Hyeuntae;Lee Keyseo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.5A
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    • pp.389-396
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    • 2005
  • In this paper, we design AVTMRWFSV(All Voting Triple Modular Redundancy With Fail-Safe Voter) System with a fail-safe output voter architecture and analyze RAMS(Reliability, Availability, Maintainability, Safety) as system failure rate. This system is compared with AVTMR system for RAMS(Reliability, Availability, Maintainability, Safety) with Markov modeling, and we can see that the system safety of AVTMRWFSV is more profitable than that of AVTMR. The dependability of AVTMRWFSV system is higher than that of AVTMR. Especially, safety is very profitable. So, this kind of system can be applied to embedded communication system and life critical systems - railway, airplane, ship, nuclear control system and so on.

A Study on the Effective Educational and Promotional Strategies for the Special Act on the Safety Management of Children's Dietary Life (어린이 식생활 안전관리 특별법에 관한 효과적 교육 및 홍보 방안 연구)

  • Hong, Jin-Im;Jeong, Hee-Sun
    • Culinary science and hospitality research
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    • v.18 no.5
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    • pp.176-189
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    • 2012
  • This study was conducted to investigate the effective educational and promotional strategies for the Special Act on the Safety Management of Children's Dietary Life on the basis of the survey conducted on parents. First of all, its result showed that most parents are well aware of the main contents of the law. They answered that, when choosing safe favorite food for children, the most important part is the article "Regulations on the standards for children's favorite food should be reinforced." As for the index of safety management for children's dietary life, most respondents think safety the most important; housewives and nuclear family members choose safety (p<.01), while large family members do nutrition. For the question asking how they get the information on safety management for children's dietary life, most of them answered that they generally use mass media, family and friends as a reference. Those with high income usually get the information from special books, those between 30s and 50 from mass media, and those with college graduates from civil social groups (p<.05). In case of taking the safety education programs for children's dietary life, they told that the most necessary information is concerned with hygienic dietary life and nutrition labeling on processed food; housewives are interested in the latter, while working people in the former (p<.05). As a method of informing parents of the Special Act on the Safety Management of Children's Dietary Life, mass media such as TV and radio, and school education are suggested in this survey. Therefore, this study proposes that mass media be considered as the most effective way of promoting the Special Act on the Safety Management of Children's Dietary Life and getting information concerning the law.

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Endoscopic transthoracic sympathectomy: An efficient and safe method for the treatment of hyperhidrosis (흉강내시경을 이용한 교감신경절 절제술 -다한증의 치료를 위한 효과적이고 안전한 방법-)

  • 최순호;한재오;양현웅;최종범
    • Journal of Chest Surgery
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    • v.31 no.7
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    • pp.697-702
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    • 1998
  • Hyperhidrosis of the palms, axillae, and the face has a strong negative impact on the quality of life for many people. Existing nonsurgical therapeutic options are far from ideal. A definitive cure can be obtained by upper thoracic sympathectomy. The traditional open surgical technique is a major procedure; few patients and doctors have found that risk-benefit considerations favor surgery. Endoscopic minimal invasive surgical techniques are now available. We investigated whether endoscopic ablation of upper thoracic sympathetic chain(T2-4) is an efficient and safe treatment of hyperhidrosis. We treated 40 patients with bilateral endoscopic transthoracic sympathectomy. There were no mortalities, life-threatening complication, no treatment failures occurred in 40 patients. After a short-term follow-up, 100% of the patients reported satisfactory results. Endoscopic transthoracic sympathectomy is an efficient, safe, and minimally invasive surgical method for the treatment of palmar, axillary hyperhidrosis.

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A Study on Modification of Industrial Accident Indicator Considering Working Environment Change (근로 환경 변화를 고려한 산업재해지표 수정 방안에 관한 연구)

  • Eum, Tae Soo;Shin, Eun Taek;Song, Chang Geun
    • Journal of Korean Society of Disaster and Security
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    • v.14 no.4
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    • pp.1-7
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    • 2021
  • Although the working environment has changed significantly compared to the past, such as the implementation of the five-day work week and the aging of the population, it is not reflected in the current industrial accident index calculation such as frequency rate, severity rate, and safe T-score. In this study, statistical data were used to understand time-series trends such as increase in life expectancy, working age, shortening of working hours, and average age of death by accident. As a result of time series trend analysis of statistical data, life expectancy increased to 83.3 years, and the legal working age was raised to 65 years due to the aging of the population. Also, with the advent of the 5-day work week since 2001, the average annual working hours decreased to 2008.1 hours. It can be confirmed through statistical data that these phenomena are applied to the current working environment due to a complex action, and these environmental changes affect the calculation results of the industrial accident index.

Drinking behavior survey of university students in Jeju for the safe campus life (안전한 대학생활을 위한 제주지역 대학생들의 음주행동연구)

  • Kim, Hyo-Sil;Lee, Young-Ah;Kim, Soo-Jin;Chae, Soo-Gyung;Lim, Jin-Hyung
    • The Korean Journal of Emergency Medical Services
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    • v.20 no.2
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    • pp.127-144
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    • 2016
  • Purpose: The purpose of this study was to investigate the drinking behavior of university students in Jeju for the safe campus life. Methods: A self-reported questionnaire was completed by 549 students in 4 universities in Jeju. The data were analyzed by t-test, one way ANOVA, and multiple regression using SPSS Win 19.0 program. The questionnaire instruments consisted of Alcohol Use Disorders of Identification Test-Korea (AUDIT-K) and Life Stress Scale for College Students adapted by Chon. Results: The alcohol consumption rate of participants accounted for 96.2%. The binge drinking rate in female students were 33.9% and that in male students was 29.5%. The result by scoring AUDIT showed that 30.7% of participants were normal drinking group, 36.0% were hazardous drinking group, and 33.3% were estimated alcohol abuse group. The average score of stress was 1.45 by Likert 4 point scale. The female students tended to have more stresses than male. The most important influencing factors on drinking behavior were the first alcohol drinking(${\beta}=-.250$, p< .001), gender(${\beta}=.202$, p< .001), and relationship problem(${\beta}=.116$, p < .05). Conclusion: The drinking rate of university students revealed higher than that in other age groups. So the early systematic education is strongly recommended to prevent the physical and mental side effects.