• Title/Summary/Keyword: Protection methods

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A Study on The Comparative Survey of Expression Methods for Fire Safety Performance in Korea and Japan (화재안전성능분야에 대한 표현방법에 관한 한.일 의식조사 비교 연구)

  • Koo, In-Hyuk;Oh, Sung-Hae;Seo, Kwang-Hyun;Lee, Jae Young;Sato, Hiroomi;Kwon, Young-Jin
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • 2008.11a
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    • pp.27-34
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    • 2008
  • As for the performance related to a fire safety like fire resistance efficiency and evacuation safety etc. It is the ain of this study to investigate the comparative survey of expression methods for fire safety performance in Korea and Japan. The results of this study that there are so difference between Japan and Korea and suggests that the necessity for converting the fire risk calculated by an advanced technique into a simple expression.

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Fracture and Protection Technologies against Impulse of Power Arresters (전력용 피뢰기의 임펄스에 의한 파손과 대척 기술)

  • 한세원;조한구;김석수
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.190-193
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    • 2001
  • ZnO varistors have been widely used to protect power system and electronic system against overvoltages based on their excellent nonlinearity. In order to increase their protection capability, the fracture and protection technologies of arresters have to study according to their applications, namely ImA DC voltage, leakage currents, impulse residual voltages, withstanding capability to impulse surge, and energy absorption capability. ZnO varistors which have nonlinear current-voltage characteristic name a number of failure mechanism when ZnO elements absorb surge energies. Failure mode by thermal stress and Pin hole are among the most common failure mechanism at the high current surge current. In this study, the fracture mechaism of power arresters are introduced and protection technologies are researched. In particular the effect of thermal stress by surge currents to ZnO elements and methods against arc surge energy through withstand structure design of arrester are discussed.

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An Experimental Study on the Corrosion Characteristics of Reinforcing Steel in Concrete by the Accelerated Corrosion Test (부식촉진시험에 의한 콘크리트 내의 철근의 부식특성에 관한 실험적 연구)

  • 배수호;정영수;김년산;권영우;권혁진
    • Proceedings of the Korea Concrete Institute Conference
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    • 2000.10a
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    • pp.503-507
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    • 2000
  • The corrosion protection methods of reinforcing steel in concrete are the various methods such as increasing thickness of cover concrete, using of reinforcing bars coated with epoxy, dosage of corrosion inhibitor as concrete admixture, cathodic protection method and etc. In this study, the performance of corrosion protection was investigated for the test specimens using corrosion inhibitors and cathodic protection, respectively. For this purpose, the accelerated corrosion tests for reinforcing steel were conducted according to the periodic cycles(140 days) of wetting($65^{\circ}C$, 90% R.H) and drying period($15^{\circ}C$, 65% R.H) for the test specimens. As a result, it can be concluded from the test that the effect of corrosion inhibitor was found to be variable with products, the cathodic protection method was found to be independent of salt concentration in concrete.

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Effective Protection Methods of Household Electric Appliances. from Lightning Surges (가정용 전기기구의 효과적인 뇌서지 보호기법)

  • 이복희;강성만;엄주홍;이수봉;길형준;구본완;안창환
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.53 no.3
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    • pp.149-156
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    • 2004
  • This paper deals with the effective protection method for the household electric appliances against lightning surges invading from the Power lines. Direct or induced lightning is the main cause of the breakdown of household electric appliance. The most effective protection method is to install SPDs(surge protective devices) at household electric appliances. If SPDs were not installed at most household electric appliances, it is necessary to install SPDs on the mains. Therefore the propagation aspect and protection methods of lighting surges coming into household electric appliances through the mains was experimentally investigated. The in actual-sized test circuits results of protection method for 8 household electric appliances including computer monitors and TV set could be summarized as follows: The breakdown characteristics of household electric appliances from lightning surges were significantly changed with the their input impedance. Namely, the types of input impedance are classified into infinite, resistive or inductive impedances. Especially, the monitor for computer with inductive input impedance from lightning surges was relatively weak against lightning surges. It was confirmed that the self inductance of branch circuits on the mains have protection effect for household electric appliances against lightning surges invading from the power lines. Also the varistors installed at cabinet panel or circuit-breaker were more effective than multi-tap outlet with varistors. When installed varistors in cabinet panel and multi-tap outlet together, the surge protection effect is much more excellent in technical and economical aspects.

Antiserum Preparation of Recombinant Sweet Potato Latent Virus-Lotus (SPLV-Lotus) Coat Protein and Application for Virus-Infected Lotus Plant Detection

  • He, Zhen;Dong, Tingting;Chen, Wen;Wang, Tielin;Gan, Haifeng;Li, LiangJun
    • The Plant Pathology Journal
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    • v.36 no.6
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    • pp.651-657
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    • 2020
  • Lotus is one of the most important aquatic vegetables in China. Previously, we detected sweet potato latent virus from lotus (SPLV-lotus) and found that it has highly significant sequence diversity with SPLV-sweet potato isolates (SPLV-sp). Here, we developed serological methods for the detection of SPLV-lotus in Chinese lotus cultivation areas. Based on the high sensitivity of SPLV-lotus coat protein antiserum, rapid, sensitive and large-scale diagnosis methods of enzyme-linked immunosorbent assay (ELISA) and dot blot in lotus planting area were developed. The established ELISA and dot blot diagnostic methods can be used to detect SPLV-lotus from samples successfully. And our results also showed that the SPLV-lotus and sweet potato isolates appeared clearly distinction in serology. Our study provides a high-throughput, sensitive, and rapid diagnostic method based on serology that can detect SPLV on lotus, which is suggested to be included in viral disease management approach due to its good detection level.

Lifetime of Insoluble Anode for Cathodic Protection on Concrete Construction

  • Sohn, Kicheon;Chang, Hyunyoung;Kim, Youngsik
    • Corrosion Science and Technology
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    • v.4 no.2
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    • pp.56-59
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    • 2005
  • In rebar concrete structure, the corrosion of rebar can arise the deterioration of concrete structure and may affect the safety of the whole system. Recently, several methods for corrosion protection have been used and are more important for concrete structure using the sand including chloride ion. Among several protections, electrical cathodic protection has been expected to be one of the most useful methods in corrosion protection for reinforcement of concrete structures. The anode for cathodic protection needs high current density, high corrosion resistance and low overvoltage. To fill up the special qualities, the insoluble anodes were developed and these anodes were coated with metal oxide of $TiO_2$, $ZrO_2$, $RuO_2$, and $IrO_2$. Lifetime of these anodes can be one of the important factors affecting the lifetime of concrete structure in cathodic protection. In this work, several anodes were made by sol-gel method and thermal decomposition method and the lifetime of these anodes was evaluated by NACE international standard test method, TM 0294-94. Also, we did analyze the properties of coated metal oxides.

A Study on the Economic Evaluation of Thermal Spray Methods for the Corrosion Protection of Steel (금속용사 방식공법의 경제성 평가에 관한 연구)

  • Jung Sung-Ho
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2005.05a
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    • pp.13-16
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    • 2005
  • Generally, as corrosive protection processing of a steel structure, zinc galvanizing and heavy duty coating paint are applied. However, zinc galvanizing has the difficulty of restriction of a size, or on-site construction. Moreover, heavy duty coating paint has a problem with many administrative and maintenance expenses with short problem of adhesion, corrosion generating of a damage portion, and maintenance management cycle. In this study, a salt water spray test, CASS test, and the electrochemistry examination were carried out for the thermal metal spray method of construction for corrosive protection performance evaluation. Moreover, the corrosive protection life of a thermal metal spray method of construction was quantitatively calculated on the basis of this experiment. in consideration of LCC, the economical efficiency of a general corrosive protection method of construction and a thermal metal corrosive protection method of construction was compared. Consequently, although initial construction expense was estimated 16 to $30\%$ high, as for a thermal metal spray method of construction, it turns out that the administrative and maintenance expenses for 100 years became cheap 9.3 to 13 or more times.

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Current Status of Internal Dosimetry Methods and Radiological Regulations in Korea, Ukraine and European Community

  • Lee, Tae-Young;Lee, Jong-Il;Berkovski, Vladimir
    • Journal of Radiation Protection and Research
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    • v.28 no.1
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    • pp.65-73
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    • 2003
  • The paper discusses results of recent international intercomparison exercises on internal dose assessments, status of up to date internal dosimetry methods and the radiological legislation developed and implemented in Korea, European Union and Ukraine. The system of radiation protection in Korea is based on the Korean Atomic Energy Regulatory Enforcement on Safety Standards (Ministry Notice No. 2001-2). The notice is based on the recommendations in ICRP Publication 60 (1990) and IAEA Basic Safety Standards (1996). But the full implementation of the notice by the end of the year 2002 is not required because of the socio-economic situation and inexperience in internal radiation dosimetry Regulatory framework for internal radiation dosimetry is under development toward the full implementation of the notice from January 1, 2003. The system of radiation protection in Ukraine is based on the National radiation protection regulatory code NRBU-97. The code was developed and adopted in 1998 and replaced the Regulations of Former Soviet Union. The document is based on the ICRP Publication 60, Euratom Directive 96/29 and IAEA Basic Safety Standards (1996). The transitional period of 5 years (effected till January 2003) is established for implementation of all requirements of this new regulation. The system of radiation protection in the European Community is based on the Council Directive 96/29/Euratom, adopted in 1996 and enforced from 13 May 2000. Directive 96/29/Euratom has the status of the European law.