• Title/Summary/Keyword: Protection methods

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The verification of the application of grouting in the bottom protection work of sea dikes in the field (그라우팅을 통한 방조제 바닥보호공 차수공법 현장 적용성 검증)

  • Lee, So-Yeal;Choi, Sae-Kyung;Jeong, Il-Han
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.09a
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    • pp.29-39
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    • 2010
  • By understanding the construction process of sea dikes and the current state of the thickness and speed of fluid in the bottom layer protection work of final closure gaps, a construction method applicable for the blocking of bottom layer work will be selected. The three construction methods selected will be tested in site through various methods, and the reinforcement of bottom layer protection and impervious effect will be verified. The verification results are as follows: 1) The overall riprap layer were 0.5~1.0m thicker than planned so that the grouting depth and grout input amount increased 2) The applied construction methods permeability of riprap layers were improved from $\alpha{\times}10^{-2}cm/s$ before the construction to $\alpha{\times}10^{-4}cm/s$ after construction. 3) The results of core extraction in order to grossly verify the hardening time and durability allowed the identification of grout injection effect. The amount of filling of the injection was difficult to judge because the slime in many areas made the reading of borehole photography difficult.

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Initiating Events Study of the First Extraction Cycle Process in a Model Reprocessing Plant

  • Wang, Renze;Zhang, Jiangang;Zhuang, Dajie;Feng, Zongyang
    • Journal of Radiation Protection and Research
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    • v.41 no.2
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    • pp.117-121
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    • 2016
  • Background: Definition and grouping of initiating events (IEs) are important basics for probabilistic safety assessment (PSA). An IE in a spent fuel reprocessing plant (SFRP) is an event that probably leads to the release of dangerous material to jeopardize workers, public and environment. The main difference between SFRPs and nuclear power plants (NPPs) is that hazard materials spread diffusely in a SFRP and radioactive material is just one kind of hazard material. Materials and Methods: Since the research on IEs for NPPs is in-depth around the world, there are several general methods to identify IEs: reference of lists in existence, review of experience feedback, qualitative analysis method, and deductive analysis method. While failure mode and effect analysis (FMEA) is an important qualitative analysis method, master logic diagram (MLD) method is the deductive analysis method. IE identification in SFRPs should be consulted with the experience of NPPs, however the differences between SFRPs and NPPs should be considered seriously. Results and Discussion: The plutonium uranium reduction extraction (Purex) process is adopted by the technics in a model reprocessing plant. The first extraction cycle (FEC) is the pivotal process in the Purex process. Whether the FEC can function safely and steadily would directly influence the production process of the whole plant-production quality. Important facilities of the FEC are installed in the equipment cells (ECs). In this work, IEs in the FEC process were identified and categorized by FMEA and MLD two methods, based on the fact that ECs are containments in the plant. Conclusion: The results show that only two ECs in the FEC do not need to be concerned particularly with safety problems, and criticality, fire and red oil explosion are IEs which should be emphatically analyzed. The results are accordant with the references.

Advanced Cathodic Protection Modeling Associated with Coating Degradation Conditions

  • Im, Gwan-Jin;Kim, Ki-Joon;Lee, Myung-Hoon
    • Corrosion Science and Technology
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    • v.8 no.5
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    • pp.177-183
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    • 2009
  • There are two effective methods in use to protect ship ballast tank against corrosion. One is paint coating and the other cathodic protection(CP). The conventional cathodic protection design has mainly relied on the expert's experience. During the last two decades computer modeling has been significantly developed as an advanced design technology for cathoidic protection systems not only for ships, but also for offshore structures. However the present computer modeling of cathodic protection systems have some limitations simulating corrosion in the ballast tank with a deteriorated coating. In this study, "coating breakdown factor" considering coating degradation states with time has been attempted to improve the cathodic protection modeling using the data from literatures.

Optimal Operation Methods of Protection Devices in Distribution Systems with PV Systems (태양광전원의 연계에 의한 배전계통 보호기기의 최적 운용방안에 관한 연구)

  • Kim, Byeon-Gi;Park, Jae-Beom;You, Kyeong-Sang;Rho, Dae-Seok
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.8
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    • pp.1485-1491
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    • 2011
  • This paper deals with the technical problems for the protection devices, by simulating test facilities of protection coordination for Photovoltaic systems. In order to analyze the operation characteristics for the protection devices in the case that the Photovoltaic systems with bi-directional power supply are located in the feeder, this paper proposes the test facilities composed of model distribution system, protection device and model Photovoltaic systems. By performing the simulation for operation characteristics for the protection devices based on the test facilities, this paper presents the malfunction mechanism for the protection devices. The test results show that this paper is practical and effective for the technical guideline for the Photovoltaic systems.

Application of Cold Weather Concrete using Accelerator for Freeze Protection (내한촉진제를 사용한 한중콘크리트의 현장적용)

  • Park, Sang-Joon;Won, Chul;Lee, Sang-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2003.05a
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    • pp.13.2-17
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    • 2003
  • When fresh concrete is exposed to low temperature, the concrete may suffer frost damage due to freezing at early ages and strength development may be delayed. One of the solution methods to resolve these problems is to lower freezing temperature of concrete by the use of chemical admixture called Accelerators for Freeze Protection. In this study, it was the results of appling cold weather concrete using Accelerator for Freeze Protection in the Daewoo Trump world field. Before the application of the cold weather concrete using accelerator for freeze protection, we executed the some test in the laboratory and mock-up test in the field. We examined the manifestation of compressive strength complying with the amount of Accelerators for Freeze Protection and curing conditions, and then made a selection of most suitable amount of Accelerators for Freeze Protection.

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Paramedical students' ethical values, awareness, and practice toward medical information protection (응급구조학과 대학생들의 윤리적 가치관과 의료정보보호에 대한 인식 및 실천)

  • Choi, Bo-Ram
    • The Korean Journal of Emergency Medical Services
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    • v.24 no.1
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    • pp.93-102
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    • 2020
  • Purpose: The purpose of this study was to investigate the ethical values of paramedics and their awareness and practice of medical information protection protocols. Methods: A survey was conducted involving 300 university students majoring in a four-year paramedical education program at two universities in Daejeon and Chungnam. Ultimately 220 surverys were subjected to analysis. Results: There was a significant difference in students' perception of medical information protection according to the need for education on medical information protection protocol (p=0.022); however, there were no significant differences in the practice of these protocols. The idealism tendency was positively correlated with the awareness of medical information protection (r=.332, p=.000) and the practice of medical information protection (r=.309, p=.001). A tendency toward relativism was significantly associated with the awareness of medical information protection (r=.138, p=.040) and not significantly related to the practice of medical information protection protocols. The tendency toward idealism tended to have a significant positive effect on the awareness of medical information protection protocols (β=.318, t=4.777, p=.000) and the degree of practice (B=.369, t=3.456, p=.001). Conclusion: Appropriate educational programs for medical information protection are needed. These programs should adhere to the characteristics of the department by linking with the training institution.

Protection Switching Methods for Point-to-Multipoint Connections in Packet Transport Networks

  • Kim, Dae-Ub;Ryoo, Jeong-dong;Lee, Jong Hyun;Kim, Byung Chul;Lee, Jae Yong
    • ETRI Journal
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    • v.38 no.1
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    • pp.18-29
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    • 2016
  • In this paper, we discuss the issues of providing protection for point-to-multipoint connections in both Ethernet and MPLS-TP-based packet transport networks. We introduce two types of per-leaf protection-linear and ring. Neither of the two types requires that modifications to existing standards be made. Their performances can be improved by a collective signal fail mechanism proposed in this paper. In addition, two schemes - tree protection and hybrid protection - are newly proposed to reduce the service recovery time when a single failure leads to multiple signal fail events, which in turn places a significant amount of processing burden upon a root node. The behavior of the tree protection protocol is designed with minimal modifications to existing standards. The hybrid protection scheme is devised to maximize the benefits of per-leaf protection and tree protection. To observe how well each scheme achieves an efficient traffic recovery, we evaluate their performances using a test bed as well as computer simulation based on the formulae found in this paper.

A Study on the Copyright Survey for Design Protection in Metaverse Period

  • Kim, Gokmi;Jeon, Ju Hyun
    • International journal of advanced smart convergence
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    • v.10 no.3
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    • pp.181-186
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    • 2021
  • Among human intellectual creations, the right granted by law to what is worth protecting is defined as intellectual property rights. Copyright is a legal right to creative finished products made by individuals, and in recent years, this legal right has been recognized as very important. In other words, copyright is a system created to protect the rights of individuals who created creations and to recognize their efforts. Works subject to copyright vary from poetry, thesis, novels to designs, paintings, music, and architecture, and the scope of the subject is gradually expanding. Recently, research has begun on how far the Metaverse design area absorbed into the real world among works. Computer-generated video productions and software program works are also subject to digital copyright protection, but it is also true that the interpretation of the author protection law for works, designs, and trademarks in the virtual world is unclear. This study aims to analyze copyrights based on case studies and theoretical backgrounds on copyright protection and to discuss the protection limitations of Metaverse design in the virtual world. In other words, the direction for the protection of Metaverse design is presented through clear distinction and definition of copyright protection in the tertiary virtual world. This study aims to present methods for design copyright protection in the era of Metaverse, respect copyright holders' creative activities, and develop our culture through protection of creations.

A Study on Improvement of Cathodic Protection Design of Harbour Marine Steel Structure (항만 강관 구조물의 음극방식설계 개선방안에 관한 연구)

  • 김성종
    • Journal of Advanced Marine Engineering and Technology
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    • v.21 no.5
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    • pp.584-590
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    • 1997
  • Harbour marine steel structures, which are served in severe marine environment, should be protected in appropriate method to reduce corrosion problems. Cathodic protection, one of the protection methods in terms of practical and economical point of view is being widely used to marine steel structures mentioned above. Recently it has been reported that the life of Al alloy anode with sacrificial anode for protection of harbour marine steel structures was shortened significantly than the original design life. In this study, the optimum cathodic protection design of harbour marine steel structures was investigated with parameter of sea water pollution degree.

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A Fundamental Research on the Safety Facilities of Railroad (철도 선로안전시설에 관한 기초연구)

  • Lee Seong-Won;Kim Seung-Hwan;Shin Seung-Kyo;Kim Tae-Wook
    • Proceedings of the KSR Conference
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    • 2005.05a
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    • pp.550-555
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    • 2005
  • In this research, safety requirements for guard rail, buffer stop, car stop scotch block, protection device, fire protection facilities, safety siding, escape facilities and inundation protection facilities are studied to establish a standard. First, various kinds of guard rails and their construction methods are investigated. Researches on the level difference of main track and guard rail, joint, length, and fastening force of guard rail are done. Second, the classification of buffer stop and car stop scotch block and its characteristics are examined, and the impact force, speed limit and capacity of buffer stop are summarized. Details of protection device, fire protection facilities, safety siding, escape facilities and inundation protection facilities are also investigated. From this fundamental research results, basic data on the safety facilities of railroad system are established.

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