• Nuclear Engineering and Technology
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• v.55 no.5
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• pp.1924-1934
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• 2023

In this study, the probabilistic fatigue life model for Ni-base alloys was developed based on the Weibull distribution using statistical analysis of fatigue data reported in NUREG/CR-6909 and the new fatigue data of Alloy 52M/152 and 82/182. The developed Weibull model can consider right-censored data (i.e., non-failed data) and quantify the improved safety (or reliability) based on the level of failure probability. The overall margin in the current fatigue design limit model (ASME design curve + NUREG/CR-6909 F_en model) is similar to that of the Weibull model with a cumulative failure probability of approximately 2.5%. The margin in the current fatigue design limit model demonstrated inconsistencies for the Ni-base alloy weld data, whereas the Weibull model showed a consistent margin. Therefore, the Weibull model can systematically mitigate the excessive safety margin.

• Annals of Occupational and Environmental Medicine
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• v.35
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• pp.50.1-50.11
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• 2023

Background: The rise in telecommuting or non-face-to-face work owing to the coronavirus disease 2019 pandemic has fueled conversations regarding the "right to disconnect." Although evidence suggests that receiving work-related communications through telecommunication devices outside of work hours may lead to various symptoms and illnesses, limited research has been undertaken on these symptoms. This study therefore aims to investigate the correlation between receiving work communications through telecommunication devices after work hours and the occurrence of work-related headaches and eyestrain in full-time, non-shift white-collar workers. Methods: This study used data from the 6th Korean Working Conditions Survey. The frequency of using telecommunication devices for work purposes outside of working hours was divided into five categories: "Every day," "Several times a week," "Several times a month," "Rarely," and "Never." Work-related headaches and eyestrain were categorized based on a "yes" or "no" response to the survey questions. Descriptive statistics, χ² tests, and multiple logistic regression analyses were performed using SPSS 27.0. Results: After adjusting for sex, age, income level, education, occupation, workplace size, work hours, and sleep disorders, the odds ratio (OR) of work-related headaches and eyestrain based on frequency of telecommunication device usage were as follows: "rarely" (OR: 1.292; 95% confidence interval [CI]: 1.111-1.503), "several times a month" (OR: 1.551; 95% CI: 1.249-1.926), "several times a week" (OR: 1.474; 95% CI: 1.217-1.784), and "every day" (OR: 1.548; 95% CI: 1.321-1.813). Conclusions: Employees who use telecommunication devices for work after regular hours are more susceptible to experiencing work-related headaches and eyestrain compared to those who do not. However, there is a dearth of research examining the physical and mental health impacts of using telecommunication devices for after-hours work. Furthermore, the existing preventative measures in Korea are insufficient. Consequently, it is imperative to develop effective measures and conduct additional research to address this issue.

• Ocean and Polar Research
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• v.37 no.4
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• pp.341-356
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• 2015

A nation has a sovereign right to develop and use its natural resources according to its policies with regard to development and the relevant environment. A nation also has an obligation not to harm other countries or damage environments of neighboring countries as consequences of such actions of developments or use of natural resources. However, international precedents induce a nation to take additional actions not to cause more damages from the specific acts causing environmental damages beyond national borders, when such acts have economic and social importance. That is to say that there is a tendency to resolve such issues in a way to promote the balance between the mutual interests by allowing such actions to continue. A solution to China's Three Gorges Dam dilemma based on a soft law approach is more credible than relying on a good faith approach of national responsibilities and international legal proceedings since the construction and operation of the dam falls within the category of exercising national sovereign rights. If a large scale construction project such as the Three Gorges Dam or operation of a nuclear power plant causes or may cause environmental damage beyond the border of a nation engaged in such an undertaking, countries affected by this undertaking should jointly monitor the environmental effects in a spirit of cooperation rather than trying to stop the construction and should seek cooperative solutions of mutual understanding to establish measures to prevent further damages. If China's Three Gorges Dam construction and operation cause or contain the possibility of causing serious damages to marine environment, China cannot set aside its national responsibility to meet international obligations if China is aware of or knows about the damage that has occurred or may occur but fail to prevent, minimize, reverse or eliminate additional chances of such damages, or fails to put in place measures in order to prevent the recurrence of such damages. However, Korea must be able to prove a causal relationship between the relevant actions and resulting damages if it is to raise objections to the construction or request certain damage-prevention actions against crucial adverse effects on the marine environment out of respect for China's right to develop resources and acts of use thereof. Therefore, it is essential to cumulate continuous monitoring and evaluations information pertaining to marine environmental changes and impacts or responses of affected waters as well as acquisition of scientific baseline data with observed changes in such baseline. As China has adopted a somewhat nonchalant attitude toward taking adequate actions to protect against marine pollution risks or adverse effects caused by the construction and operation of China's Three Gorges Dam, there is a need to persuade China to adopt a more active stance and become involved in the monitoring and co-investigation of the Yellow Sea in order to protect the marine environment. Moreover, there is a need to build a regular environmental monitoring system that includes the evaluation of environmental effects beyond borders. The Espoo Convention can serve as a mechanism to ease potential conflicts of national interest in the Northeast Asian waters where political and historical sensitivities are acute. Especially, the recent diplomatic policy advanced by Korea and China can be implemented as an important example of gentle cooperation as the policy tool of choice is based on regional cooperation or cooperation between different regions.

• Korean Journal of Computational Design and Engineering
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• v.11 no.1
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• pp.67-76
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• 2006

Today the tastes of consumers change rapidly and the kinds of the products become diverse. There- fore the product life cycle becomes shorter and shorter. Moreover the save of resources and the recycling for the environmental preservation are the essential theme. On this the necessary information for the product development increases enormously. For the right use of the information the design process should be supported by the proper design tool. For this the 'design catalogue system for recycling' is suggested here. This system consists of four parts. that is, 'the existing automobile system database', 'welting principle database', 'Assessment system of the ease of disassembly' and 'one's own product development ratabase'. By the use of this system the product development period could be reduced about 30% drastically.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.24 no.2
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• pp.57-64
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• 2018

This article delves into the current status of various packaging technologies, which are currently being applied or are under development for the shelf-life extension and quality improvement of fresh and processed meat products. Traditional packaging methods include vacuum packaging, modified atmosphere packaging, and air-permeable packaging. Recently, innovative packaging methods have been introduced that utilize technologies such as barrier-films, active packaging, nanotechnology, microperforated films, far-infrared radiations, and plasma treatment. All of these packaging methods have their own merits and drawbacks in terms of shelf-life and quality maintenance. A right choice of packaging system for fresh and processed meat products must be made in accordance with the conditions of the raw material, storage, and distribution in the market and household, and while considering the environmental sustainability and consumer's expectations.

• The Journal of the Korean life insurance medical association
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• v.27 no.1
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• pp.24-32
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• 2008

The number of disabled person is increasing, and also the demand of welfare is increasing. In the developed country, the range of disabled person is broad, because the definition of disability is different among countries. On 10/Apr, 2007, the law to forbid discrimination against disabled person was announced and then it will be operated on 11/Apr, 2008, in Korea. It will need to evaluate conflict between this law and underwriting guideline. There is obvious difference between disabled and non-disabled on risk selection of medical and environmental aspect. More than 50% of disabilities are related to the diseases rather than accident. The role of underwriter is to evaluate the future risk of morbidity (admission and/or operation etc). The insurance company is required to make new product for disabled person and the underwriter has to examine the application of disabled without discrimination, and with respect for the disabled as a human right.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.202-204
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• 2006

In this paper, the detection scheme of the spatial coordinates based on stereo camera for a Transformation algorithm of an Leg-wheel Hexapod Robot is proposed. Robot designed as can have advantages that do transfer possibility fast mobility in flat topography and uneven topography through walk that use wheel drive. In the proposed system, using the disparity data obtained from the left and right images captured by the stereo camera system and the perspective transformation between a 3-D scene and an image plane, depth information can be detected. Robot uses construed environmental data and transformation algorithm, decide wheel drive and leg waik, and can calculate width of street and regulate width of robot.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11b
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• pp.35-38
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• 2005

It is widely recognized that train Is one of the most efficient and convenient ways for passenger and freight transportation. However, the environmental noise problem is occurred with the construction and service of train. The noise problems caused by train prevent people from living in a silent environment. Furthermore, this problem is related with the right to preserve one's environment. The objectives of this research are train noise measurement and analysis which might be a base-study for prediction of train noise. This paper mainly deals with the noise of the 'Semaul' train. The train noise shows distinct characteristics according to the variation of height and distance. Furthermore, the database and its interface program are developed for systematic analysis and future research.

• Toxicological Research
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• v.17 no.1
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• pp.11-15
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• 2001

This study was carried out to evaluate the irritant potential of A mouthwash in hamster cheek pouch. The test substances were applied twice daily to right pouches of hamsters for 14 consecutive days. Animals were administered with A mouthwash, Listerine, saline and control solution, respectively. In order to evaluate the irritant potential in mucosa of hamster cheek pouch, we observed clinical signs, mortality, body weight changes and gross and histopathological findings for 14 days. In all groups, there were neither dead animals nor significant changes of body weights. In addition, there were no differences between saline and A mouthwash treated group in gross and histopathological findings. Therefore, these results suggest that there was no irritant potential of A mouthwash in hamster cheek pouch.

• The Korean Journal of Emergency Medical Services
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• v.9 no.2
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• pp.101-110
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• 2005

In Korea, EMS Fund Operation seems to move the opposite direction to right way. The most initial EMS fund was consumed loan for some emergency patients without any particular results. Since 2002, the use of EMS fund also has shown a tendency to shift one side. By the results, it was 44.3% to support emergency medical centers, so called hospital EMS system and 28.4% to purchase ambulances and helicopters, and 1.6% to operate Central Medical Center, prehospital base in the EMS fund consumed in 2004. It was never supported for the environmental improvement and development of universities, colleges, and private EMS units having the primary responsibilities. The initial EMS fund using should be used for prehospital base, e.g., prehospital staffs, communications, and facilities and balanced development between public and private EMS units than any other fund using.