• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.2216-2217
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• 2008

This paper write about earth system for the prevention electric shock and a protection of equipment in england. The IEC60364 and BSI(British Standards Institution) define earthing method(IT, TT, TN-C, TN-S, TN-C-S)-BSI is british standards and in case of england almost use the TN system. TN system can classify TN-S & TN-C-S(PME). The findings on survey in england are used the TN-S system and TN-C-S system about 70% and residue 30% are used TT system and IT system from the exiting state of things.

• 전기학회논문지
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• 제63권11호
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• pp.1602-1607
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• 2014

This paper deals with the design and property analysis of 7kW-class small-scaled superconducting Linear Synchronous Motor (LSM) and testing equipment for a number of performance pre-tests prior to the development of coreless-type superconducting LSM suitable for 600km/h very high speed train. First, the basic design and property analysis are conducted before developing a small-scaled superconducting LSM model with 2-pole superconducting electromagnets, and additionally the cost-down design of the superconducting electromagnets is conducted to use less high-Tc superconducting wire. Finally, the superconducting magnet coil span is selected at 120mm, and input ground armature current of 670Aturns is required to produce 44.7N of thrust based on research findings.

• STI Policy Review
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• 제3권1호
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• pp.139-161
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• 2012

The United States National Innovation system has many distinctive aspects and its government research institutes (GRI's) play a variety of important roles within the overall system. This paper reviews issues pertaining to U.S. GRI's but within the broader concept of US science and technology policy. After presenting an overview of the GRI's in this broader context, the paper presents a brief historical analysis of changes in the roles and deployment of U.S. GRI's. After identifying unique features of GRI's (ones that separate the U.S. GRI's from other nations) the paper concludes by identifying the ways in which the U.S. experience may be relevant to other nations such as Korea. The lessons include the competition-cooperation with large-scale and multidisciplinary university research centers, the use of GRI's to promote sharing and efficiencies in fundamental scientific equipment and resources, and the ability of GRI's to accelerate the development of science and technology.

• 한국산업보건학회지
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• 제33권2호
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• pp.93-102
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• 2023

Objectives: With the evolution of direct reading sensors, it is possible to monitor several substances through telecommunication. However, there are some limitations on the use of direct reading technologies in the Occupational Safety and Health Act in South Korea, which only applies to detector tubes, noise, heat, and carbon monoxides. The number of chemicals and their amount of use have been continuously increasing in South Korea. The Ministry of Employment and Labor (MoEL) has concerns about worker's health because exposure is only covered for about 1.2% of all distributed chemicals. Using a direct reading monitor with photoionization detectors (PID-DRMs), gases and vapors chemicals can be measured. Based on the data, business owners are able to create corrective strategies, provide better working routines, and select correct respiratory equipment. PID-DRMs are less expensive and easier to handle for an owner voluntarily controlling chemicals emitted in the workplace. However, there are several limitations on using these PID-DRMs to the degree that the MoEL has not been able to select a legal monitor. The aim of this study was to review previous studies related to PID-DRMs and identify the characterization and limitation on PID-DRMs. Methods: To search for related studies on PID-DRMs, key words were used including direct reading monitors/instruments and/or photoionization detectors. Through that, four domestic and 15 international studies were reviewed. Results: Studies on PID-DRMs were conducted by chamber (enclosed, dynamic, walk-in) and in the field (experimental environment, actual environment). The concentration of PID-DRMs and charcoal tubes were compared for a single substance or mixture, or within the PID-DRMs. There was a high correlation between the two concentrations, but it did not meet the accuracy criteria (95% confidence interval, within 25%) of the NIOSH technical report (2012). In addition, differences in measured values occurred according to environmental factors (temperature, humidity) and high concentration, and concentration values tended to be underestimated due to contamination of the sensor. As a way to improve the accuracy of PID concentration, it was proposed to use correction factors, charcoal tube-based correction factors, or to calibrate the PID-DRMs in the same environment as the workplace. Conclusions: PID-DRMs can likely be used by business owners for the purpose of voluntarily managing the workplace environment, and it is expected that it will be possible to use them as legal equipment if a PID sensor can be upgraded and the limitations of the sensor (temperature, humidity, high concentration evaluation, sensor pollution) can be overcome in the near future.

• 한국산업보건학회지
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• 제21권2호
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• pp.110-115
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• 2011

Objectives: The aim of this study is to survey for finding asbestos containing equipment at the laboratories using picture based questionnaire and polarized light microscopic analysis. Methods: This study was conducted from 2009 to 2010 at a university in Seoul. In 2009, picture based questionnaire was distributed to 100 laboratories during the regular laboratory air quality monitoring. In 2010, we emailed all professors of the same university who have laboratories to participate voluntarily this survey. For the laboratories consented to participate survey, picture based questionnaire was distributed and collected. Suspected asbestos containing material and apparatus were collected at the laboratories which replied they have suspected material and equipment. Collected samples were analyzed with polarized light microscope at the laboratory accredited by ministry of employment and labor in Korea. Results: Total of 18 out of 100 laboratories reported that they had suspected asbestos containing equipment in 2009. Twenty-three samples were collected and three samples (13%), one heating mantle and two pairs of insulation gloves, contained asbestos. Thirty four laboratories reported they had suspected asbestos containing material or equipment in 2010. Sixty samples were collected and four of them (6%), two pairs of insulation gloves, one packing rope in dry oven and, one pair of tongs, contained asbestos. All founded asbestos was chrysotile and the content of chrysotile was more than 90% for all equipment except heating mantle which has less than 1%. Conclusions: We confirmed that asbestos was still used at the laboratories though strict regulations on asbestos use in Korea. The method of picture based questionnaire invented in this study could be applied for asbestos survey to other research institute or university where there are many laboratories because of its simplicity and accessibility without huge man power, cost and time.

• 조명전기설비학회논문지
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• 제27권7호
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• pp.24-28
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• 2013

Fire-hited electrical equipment has possibility of deterioration. So its replacement is essential in terms of safety. However, the economic burden is increased. Therefore, the replacement or re-use of it is to be determined by tests. But the research of Integrity Assessment on Fire-hited electrical equipments is very rare. In this paper, we tested to determine the replacement or re-use of Fire-hited vacuum circuit breaker. And provided the data for the integrity assessment through the analysis of its deterioration.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.270-273
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• 2001

Electrical tree is studied widely by manufacture state of insulating material fare and blazing fire diagnosis system of use in phenomenon of part discharge that happen for main cause of dielectric breakdown of equipment for electric power. Use process that draw tree pattern here measuring above zero to study special quality of this electricity tree, real-time processing by image processing is proposed because reproduction of tree blazing fire process drops and pattern of tree is difficult correct quantification of tree growth by existent visual observation by involution. This research presents general process that need in image processing of tree blazing fire, and that remove various noises that happen in above zero by measuring electrical tree dividing background and complete view in measured above zero taking advantage of specially proposed complete view object abstraction techniques effectively and quantification of tree becomes easy naturally, can apply to dielectric breakdown estimate because can chase growth process of tree.

• Safety and Health at Work
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• 제8권1호
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• pp.49-58
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• 2017

Background: This study determined current status of laboratory biosafety in Nigerian veterinary research facilities. Methods: A questionnaire was developed to obtain information from researchers across Nigeria from July 2014 to July 2015. Information regarding demographics, knowledge of laboratory biosafety, availability and proper use of personal protective equipment (PPE), any priority pathogens researched, attitude on and use of standard laboratory practices, and biosafety awareness was obtained using a numeric scoring system. Data were analyzed with descriptive statistics, and univariate and multivariate logistic regression. Results: A total of 74 participants from 19 facilities completed the questionnaire. General knowledge scores ranged from 3 to 28 (out of 28 possible points), with 94.6% of respondents receiving low scores (scores < mean + 1 standard deviation). Very few (17.6%) reported availability or use PPE. Many participants (63.5%) reported no access to biosafety level (BSL)-1-3 facilities. None reported availability of a BSL-4 facility. Knowledge scores pertaining to biosafety management practices ranged from 0 to 14 (out of 14 possible points) with 47.3% of respondents receiving good scores (scores > mean + 1 standard deviation). Only 16.2% of respondents (from four facilities) reported having biosafety officers. Rabies virus was the most researched pathogen (31.1% of respondents). The majority (71.6%) were unaware of laws guiding biosafety. Researchers [odds ratio (OR) = 18.0; 95% confidence interval (CI): 1.63, 198.5; p = 0.023], especially in BSL-2 (OR = 258.5; 95% CI: 12.71, 5256; p < 0.001) facility of research institute (OR = 25.0; 95% CI: 5.18, 120.6; p < 0.001), are more likely to have adequate access to and properly utilize biosafety devices and PPE. Conclusions: Current knowledge of laboratory biosafety is limited except among a few researchers.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.252-256
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• 2001

The rapid development of communication equipment and information processing technology has led to a constant improvement in cordless communication. Lithium ion batteries used in cellular phones and laptop computers, in particular, have been in the forefront of the above revolution. These batteries use high value added raw materials and have a high and stable energy output and are increasingly coming into common use. The development of the material for the negative terminal has led to an improvement in the quality and efficiency of the batteries, whereas a reduction in the cost of the battery by researching new materials for the positive anode has become a research theme by itself. These long life batteries, it is being increasingly realized, can have value added to them by recycling. Research is increasingly being done on recycling the aluminum case and the load casing for the negative diode. This paper aims to introduce the current situation of recycling of lithium ion batteries. 1. Introduction 2. Various types of batteries and the situation of their recycling and the facts regarding recycling. 3. Example of cobalt recycling from waste Lithium ion secondary cell. 3-1) Flow Chart of Lithium ion battery recycling 3-2) Materials that make a lithium ion secondary cell. 3-3) Coarse grinding of Lithium ion secondary cell, and stabilization of current discharge 3-4) Burning 3-5) Grinding 3-6) Magnetic Separation 3-7) Dry sieving 3-8) Dry Classifying 3-9) Content Ratio of recycled cobalt parts 3-10) Summary of the Line used for the recovery of Cobalt from waste Lithium ion battery. 4. Conclusion.

• Nuclear Engineering and Technology
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• 제55권6호
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• pp.2034-2046
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• 2023

Industrial control systems in nuclear facilities are facing increasing cyber threats due to the widespread use of information and communication equipment. To implement cyber security programs effectively through the RG 5.71, it is necessary to quantitatively assess cyber risks. However, this can be challenging due to limited historical data on threats and customized Critical Digital Assets (CDAs) in nuclear facilities. Previous works have focused on identifying data flows, the assets where the data is stored and processed, which means that the methods are heavily biased towards information security concerns. Additionally, in nuclear facilities, cyber threats need to be analyzed from a safety perspective. In this study, we use the system theoretic process analysis to identify system-level threat scenarios that could violate safety constraints. Instead of quantifying the likelihood of exploiting vulnerabilities, we quantify Security Control Measures (SCMs) against the identified threat scenarios. We classify the system and CDAs into four consequence-based classes, as presented in NEI 13-10, to analyze the adversary impact on CDAs. This allows for the ranking of identified threat scenarios according to the quantified SCMs. The proposed framework enables stakeholders to more effectively and accurately rank cyber risks, as well as establish security and response strategies.