• Title/Summary/Keyword: Out-of-step protection

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Research on Measurement Condition Establishment of a Liquid Scintillation Counter System (액체섬광계수기 장비의 계측조건 확립에 관한 연구)

  • Park, Eung-Seop;Han, Sang-Jun;Lee, Seung-Jin;Kim, Hee-Gang;Lee, Na-Young;Mun, Ji-Yeon
    • Journal of Radiation Protection and Research
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    • v.31 no.3
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    • pp.155-164
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    • 2006
  • It is judged that there could be certainty in every process of analyzing environmental samples using Liquid Scintillation Counter. Therefore, this study focuses on quantitative evaluation on uncertainty in an effort to analyze comparatively accurately environmental samples. For this, after parameters which can have an effect on uncertainty was derived, the evaluation on each parameter was tamed out. The results of analysis of each parameter showed that the effect according to the weight difference of Teflon vial did not appear, and that standard deviations of SQP(E) averages reached saturation point at $75{\sim}90$ sec at the result of making increases step by step the irradiation time of External standard, and that values measured by repeat method produces good results compared with replicate. Also, conclusion was derived that analysis on sample after it is left in cold and dark room at least above 1,000 minutes have to be carried out, and the result of carrying out verification on results measured as well as equipment itself using radioactivity-error-analysis and chi-square test, resonable result was derived.

Analysis of Ecological Landscape Planning and Policy in Germany (독일의 생태학적 조경계획 정책분석 -독일 자연환경보존법을 중심 으로-)

  • ;L, Finke
    • Journal of the Korean Institute of Landscape Architecture
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    • v.22 no.2
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    • pp.105-122
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    • 1994
  • The landscape plannings were composed of the fundamental provisions which are important factors for the city and local plannings in Germany. The State Government run institute like LOLF in NRW have been established to solve the serious ecological problems. The institute have completed the basic system covering various ecological problems, such as environmental affection analysis and ecological risk, to contribute the application of the various land-using plants. The ecological landscape plannings are regarded as major fundamental plans of environmental preservation for the plannings development. The problems about the local landscape plannings needed to be preserved ecologically are introduced into the Federal Nature Preservation Law and State Congress Law in order to carry out the environmental protection policy effectively. The local landscape plannings are divided into two-step models by the special classification system for the planning. One is build-up of an independent design separated from city plans functionally, and the other is a systematic regulation for cooperation between the local plans and ecological conservation functions. The local plannings including lands to be preserved as the Nature Preservatin Zone is classified a rest area total sectioned plains.

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Estimation of Earth Performance by Ground Potential Measurement (대지전위 실측에 의한 접지성능 평가)

  • Lee, Won-Young;Kim, Jea-Hoon;Kim, Ju-Han;Han, Sang-Ok
    • Proceedings of the KIEE Conference
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    • 2005.05b
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    • pp.51-53
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    • 2005
  • Grounding systems are responsible rot the safe operation of a power system whetehr power system fault occures or not, their performance guarantees equipmet protection and personnel safety by limited the ground potential rise and touch voltages as well as step voltages under ground fault condition. therefore, it is necessary to measure the ground resistance frequently for checing the performance of grounding system. In order to verigy the designed grounding measurement system feasibility, two comparison verifications, which are the ground resistnace measurements using the designed system on power service and off power service, are carried out for the same substation.

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Knowledge, Awareness and Health Risk Concerns on Occupational Exposure to Radiation among Firefighters in Korea (소방공무원의 직업적 방사선노출에 대한 지식, 자각 및 건강피해 우려)

  • Lee, Hyeongyeong;Yoon, Hyeongwan;Park, Jeongim
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.25 no.4
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    • pp.516-524
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    • 2015
  • Objectives: This study aims to investigate the current status of knowledge, awareness and health risk concerns on occupational radiation exposures among firefighters in Korea. The results will provide basic information for developing a prevention program to minimize adverse health effects relating to radiation exposure among firefighters. Methods: A questionnaire was composed of general characteristics of participants, and their knowledge, awareness, health risk concerns relating to occupational radiation exposure. It was distributed by email to all of 307 firefighters in Jeollabukdo in April 2014 and 259 of them (response rate 84.3%) were responded. Answers were analyzed for descriptive statistics including frequencies and percentages. SPSS/WIN 18.0 program was utilized for statistical analysis of t-test, ANOVA and Pearson's correlation. Results: The average score of radiation protection knowledge was $5.83{\pm}1.77$ ($average{\pm}SD$) out of 10. The score of awareness and health risk concerns on radiation exposure were 4.27, 3.94 out of 5, respectively. The results indicated that the knowledge on the characteristics of radiation was marginal among the firefighters, while the awareness and health risk concerns relating to radiation exposures were relatively higher comparing to other professions. Conclusions: Knowing the characteristics of potential risks is the first step for minimizing the adverse health effects relating to the risks. Therefore, it is necessary to provide adequate training and information on radiation and exposure protection methods for firefighters.

On the Japanese New Alternative Dispute Resolution System in the Financial Sector (일본의 금융분야 ADR 에 관한 검토)

  • Kim, Sun-Jeong
    • Journal of Arbitration Studies
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    • v.20 no.3
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    • pp.121-145
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    • 2010
  • In the past, ADR has not been used as frequently in Japan as it has in other parts of the industrialized world. However, though litigation is still the most utilized vehicle of dispute resolution by Japanese financial institutions, this will be changing. The New Financial ADR system, which was created by a June 2009 amendment to the Financial Instruments and Exchange Act, is meant to deal with every stage of financial-related disputes and, as such, strives to resolve disputes before they become significant and acts to ameliorate any post-ADR issues that may remain, thereby completing the FIEA's purpose to protect investors. Since the foundation of the New Financial ADR system applies to all related industries, new provisions were set out in 16 business related acts, such as the Banking Act, the Insurance Business Act, and FIEA itself. October 2010 will mark the formal introduction of a new system of financial ADR in Japan. New Financial ADR in Japan will be modeled on the Financial Ombudsman Service in the United Kingdom, but will not feature one comprehensive dispute resolution system in which one dispute resolution institution covers all disputes in the financial field. The New Financial ADR system is merely one step towards a foundation of comprehensive financial ADR such as FOS. It must be noted, however, that this all important first step was over seven years in the making, involving a great deal of discussion, debate, and compromise amongst many parts of Japanese government, business, and society. The New Financial ADR system grants participating parties the ability to stop the clock on any statute of limitations which may correspond to any future possible court cases related to the dispute,13 and further grants the ability to suspend related court proceedings while the parties are utilizing the New Financial ADR system. In addition, where financial institutions have not accepted dispute resolution proceedings or have not accepted a special conciliation proposal, the Ministry of Finance may issue an order compelling compliance if it is found that certain actions are necessary to ensure the appropriate operations of a financial institution's business. In Japan, as best practices have not yet been created.

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Effects of Ground Faults on the Safety of Persons and Low-voltage Installations in 22.9 kV-Y Distribution Systems (22.9 kV-Y 계통에서 지락고장이 인체 및 저압설비의 안전에 미치는 영향)

  • Kim, Han-Soo;Chung, Jae-Hee;Kang, Kae-Myung
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.22 no.1
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    • pp.141-148
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    • 2008
  • This paper presents experimental results on the safety of persons and protection of low-voltage equipments of the sub-station due to a single-phase ground fault in 22.9 kV-Y distribution system. In order to evaluate the hazard voltages and the stress voltage of the low-voltage(LV) equipment due to faults between high-voltage systems and earth based on the newly prescribed KS C IEC 60364 standard series, the verification tests in a 22.9[kV] neutral multiple grounding system were carried out. From the experimental results, we introduce serious problems causing some discomfort when applying KS C IEC 60364 standard series to the existing domestic distribution system and the effective protective measures against temporary overvoltages due to a ground fault in the common grounding which is combined the 22.9 kV-Y grounding and the customer's installation grounding are proposed. As a consequence, it was found that the equipotential bonding is an important prerequisite for the effectiveness of the protective measures for the safety of persons and LV equipment in the combined 22.9 kV-Y and low-voltage grounding system.

A Study on the Design of Dynamic System and Vibration Isolation System in a High-speed Press (고속프레스의 다이나믹 시스템 및 방진시스템 설계에 관한 연구)

  • Suh, Jin Sung;Jeong, Chel-Jea;Hyeon, Gi-Yong;Ryoo, Min
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.25 no.12
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    • pp.856-865
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    • 2015
  • In a high-speed press, numerous moving links are interconnected and each link executes a constrained motion at high speed. As a consequence, high-level dynamic unbalance force and unbalance moment are transmitted to the main frame of the press, which results in unwanted vibration and significantly degrades manufacturing accuracy. Dynamic unbalance force and unbalance moment inevitably transmits high-level vibrational force to the foundation on which the press is installed. Minimizing the vibrational force transmitted to the foundation is critical for the protection of both the operators and the surrounding structures. The whole task should be carried out in two steps. The first step is to reduce dynamic unbalance based upon kinematic and dynamic analyses. The second step is to design and build an optimal vibration isolation system minimizing the vibrational force transmitted to the foundation. Firstly, the dynamic design method is presented to reduce dynamic unbalance force and moment. For this a 3D CAD software was utilized and a computer program was written to compute dynamic unbalance force and moment. Secondly, the design method for vibration isolation system is presented. The method for designing coil springs and viscous dampers are explained in detail.

Complemented Maximum-Length Cellular Automata Applied on Video Encryption (비디오 암호화를 위한 여원 최대길이 셀룰라 오토마타)

  • Li, Gao-Yong;Cho, Sung-Jin;Kim, Seok-Tae
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.17 no.1
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    • pp.13-18
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    • 2017
  • With the advancement of internet technology, the importance of data protection is gaining more attention. As a possible data protection solution, we propose a novel video encryption method using complemented maximum-length cellular automata (C-MLCA). The first step for encryption is to use 90/150 CA rule to generate a transition matrix T of a C-MLCA state followed by a 2D C-MLCA basis image. Then, we divide the video into multiple frames. Once, we perform exclusive-OR operation with the split frames and the 2D basis image, the final encrypted video can be obtained. By altering values of pixel, the fundamental information in visualizing image data, the proposed method provides improved security. Moreover, we carry out some computational experiments to further evaluate our method where the results confirm its feasibility.

Korean Emotional Laborers' Job Stressors and Relievers: Focus on Work Conditions and Emotional Labor Properties

  • Lee, Garam
    • Safety and Health at Work
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    • v.6 no.4
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    • pp.338-344
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    • 2015
  • Background: The present study aims to investigate job stressors and stress relievers for Korean emotional laborers, specifically focusing on the effects of work conditions and emotional labor properties. Emotional laborers are asked to hide or distort their real emotions in their interaction with clients. They are exposed to high levels of stress in the emotional labor process, which leads to serious mental health risks including burnout, depression, and even suicide impulse. Exploring job stressors and relieving factors would be the first step in seeking alternatives to protect emotional laborers from those mental health risks. Methods: Using the third wave data of Korean Working Conditions Survey, logistic regression analysis was conducted for two purposes: to examine the relations of emotional labor and stress, and to find out job stressors and relievers for emotional laborers. Results: The chances of stress arousal are 3.5 times higher for emotional laborers; emotional laborers experience double risk-burden for stress arousal. In addition to general job stressors, emotional laborers need to bear burdens related to emotional labor properties. The effect of social support at the workplace is not significant for stress relief, unlike common assumptions, whereas subjective satisfaction (wage satisfaction and work-life balance) is proven to have relieving effects on emotional laborers' job stress. Conclusion: From the results, the importance of a balanced understanding of emotional labor for establishing effective policies for emotional laborer protection is stressed.

Effect of NOx Removal Efficiency according to Space Velocity and Linear Velocity of SCR Catalyst (SCR 촉매의 공간속도 및 선속도가 NOx 제거 효율에 미치는 영향)

  • Park, Jin-woo;Park, Sam-sik;Ku, Kun Woo;Hong, Jung Goo
    • Journal of ILASS-Korea
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    • v.21 no.2
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    • pp.71-77
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    • 2016
  • Air pollutants nitrogen oxides are inevitably generated in the combustion reaction. Its amount trend is steadily increasing because the rapid modern industrialization and population growth. For this reason, NOx is controlled to reducing the harmful components in the exhaust gas. So Marine Environment Protection Committee (MEPC) take effect 'Tier I', 'Tier II' of air pollution regulation in 2005 and 2011 respectively. According to NOx emissions are strictly regulated management of the vessel through them. In addition, since 2016 the regulation enter into force in the next step 'Tier III' was confirmed by MEPC 66th committee. It's 80% enhanced emissions limits than the 'Tier I' Alternatively these emission regulation, research is actively being carried out about exhaust gas after-treatment methods through the vessel application of Selective Catalytic Reduction(SCR). Therefore depending on the basic specification of cell density according to the Area velocity, Space velocity, Linear velocity is studied the effects of NOx removal efficiency