• Title/Summary/Keyword: Physical protection system

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A Study on Fire Protection in Nuclear Power Plants and Application of the Code and Standards for Fire Protection Systems (원자력발전소 화재방호와 소방시설 기술기준 적용에 대한 고찰)

  • Kim, Wee-Kyong;Jeong, Kee-Sin
    • Fire Science and Engineering
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    • v.26 no.6
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    • pp.38-44
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    • 2012
  • The purpose of fire protection for the nuclear power plants (NPPs) is to ensure safe shutdown state of the reactor, to minimize the release of radioactive materials to the environment, to provide physical safety of the on-site personnel, and to limit the property damage. Fire protection and extinguishing equipments are one of the important protection measures based on the defense-in-depth concept, which can promptly detect and control and extinguish those fires that do occur, thereby limiting fire damage. However, a separate evaluation process might be additionally necessary for the construction permit and operating license because the fire protection laws of the NEMA for installation standards of the fire protection systems is not fully characterized for the NPPs. It is also not easy to implement the regulations such as the performance based design concept for fire protection system of the NPPs which are characterized for a relatively low density of employee. This study suggests a guideline for the improvement of the technical standards for fire protection systems of the NPPs by evaluating the fundamental problems drawn by reviewing laws and regulatory guides relevant to fire protection and by evaluating the applicability of the KEPIC FPN in domestic nuclear power plants.

Lightning Protection of Signalling Equipments at Subway Car Depot by Equi-potential Bonding (지하철 차량기지에서의 등전위 본딩에 의한 신호시스템 낙뢰보호대책)

  • Seo, Seog-Chul;Choi, Kyu-Hyoung
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.1
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    • pp.100-105
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    • 2007
  • Signalling equipments at railroad sites are widely exposed to high voltage lightning surges. This paper presents a lightning protection system for the signalling equipments at subway car depots. The main features of the system are as follows : (1)the common grounding system between power system grounds and the signaling system grounds, (2)physical and chemical methods to reduce grounding resistivity, (3)rearrangement of lightning rods based on the rolling bal1 theory, (4)equi-potential bonding networks to minimize the potential differences between the equipments grounds. The system has been constructed at six subway car depots in Seoul metropolitan area and it is measured that the grounding resistivity are reduced to 0.266 ohms and the potential differences between devices are reduced to a negligible quantity. After the construction of the systems, it has not been reported the break-down of the signalling equipments caused by lighting surges.

A Practical Security Risk Analysis Process and Tool for Information System

  • Chung, Yoon-Jung;Kim, In-Jung;Lee, Do-Hoon
    • Journal of Information Processing Systems
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    • v.2 no.2
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    • pp.95-100
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    • 2006
  • While conventional business administration-based information technology management methods are applied to the risk analysis of information systems, no security risk analysis techniques have been used in relation to information protection. In particular, given the rapid diffusion of information systems and the demand for information protection, it is vital to develop security risk analysis techniques. Therefore, this paper will suggest an ideal risk analysis process for information systems. To prove the usefulness of this security risk analysis process, this paper will show the results of managed, physical and technical security risk analysis that are derived from investigating and analyzing the conventional information protection items of an information system.

A Study on the Mobilization of Prisoners in the Late Wartime Period (1943~1945) -with a focus on the National Protection Corps of Prisoners- (태평양전쟁 말기의 수인(囚人) 동원 연구(1943~1945) -형무소 보국대를 중심으로-)

  • Lee, Jong-Min
    • The Journal of Korean-Japanese National Studies
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    • no.33
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    • pp.67-111
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    • 2017
  • This article aims to shed light on the wartime labor mobilization of prisoners on a large scale in/across colonial Korea and beyond during the late wartime period. More specifically, this article reveals the logic and mode of mobilization, and sorts out nationwide mobilization cases in colonial Korea. To this end, this article draws on documents and magazines published by the criminal administration of the Japanese Government-General of Korea, as well as the memoirs of prisoners and prison staff including prison administrators and prison chaplains. With the onset of the wartime system, the labor work in prisons centered on the production of military supplies. In 1943, the labor mobilization began to organize the National Protection Corps and dispatch them to remote workplaces. For example, at the requests of the military, prisoners were selected and sent to Hainan Island, while others were sent to military factories and mining fields in the northern part of the country. The authorities specified and adjusted the criteria for imprisonment based on education, physical strength, and other physical and mental conditions. Unconverted ideological offenders were excluded from the mobilization, and instead put under separate control. In preparation for mobilization, the prisoners trained in military drills, received Japanese language education, and underwent assimilation as imperial subjects through the preaching in prison. In order to induce prisoners to volunteer, a legislation system based on the shortening of the prison terms, including the parole system, was also promoted under the wartime system. As a result, prisoners were forced to work harder and faster even under the lowest of wages, poor food and poor housing conditions, and they also filled vacancies in managerial positions by serving as supervisory assistants. The reward system for them, however, did not function properly towards the end of the war, and the number of escapes and infectious outbreaks, as well as mortality rates rapidly increased under the harsh conditions.

Development and Hydraulic Characteristics of Continuous Block System in River Bank Protection (I) - Development and Application Review through Hydraulic Model Test - (일체형 식생호안블록 시스템 개발 및 수리특성 연구(I) -일체형 호안블록 개발 및 수리모형실험을 통한 적용성 검토-)

  • Jang, SukHwan
    • Journal of Wetlands Research
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    • v.10 no.3
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    • pp.87-97
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    • 2008
  • This research focused on development and application feasibility for the coalesced continuous block system in river bank protection. Most of block systems in river bank are pre cast type and have some difficulties against high velocity flood condition or high pressure load, however, the continuous block system can be applied to flood damage recover as well as environmental vegetation block system in river bank. For the application review and analysis of hydraulic condition for this block system, hydraulic physical modeling was carried out. The physical model was built as a scale of 1:50 by Froude similitude measuring the water levels and the water velocities for vegetation application or not. In consequence, the water velocities were observed to decrease meanly 10.1%, and the water depths were to increase meanly 17.8% in case of the of design flood, $Q=200m^3/sec$. To verify the hydraulic physical modeling, the numerical modeling should be conducted for a close examination of vegetation application by one or two dimensional numerical analysis as a next study.

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Effects of the Contaminants in Papermaking Process Water on Physical Properties of Paper (공정수 내의 오염물질이 종이의 물성에 미치는 영향)

  • 이학래;함충현;이지영
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.36 no.1
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    • pp.16-23
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    • 2004
  • Recently the increased concerns about the cost reduction and environmental protection make the paper industry increase the closure level of papermaking system, which results in the buildup of organic and inorganic materials in the papermaking process water. Increase of the system closure causes deterioration of additive performance and provokes diverse problems in papermaking process and product quality. To investigate the effects of process water quality on the physical properties of fine papers handsheets were prepared with process water containing various amounts of inorganic and organic contaminants including calcium or sodium ions and oxidized or cationic starches. Inorgainc and organic materials did not show any significant effect on the physical properties of handsheets. Recycled GCC showed the same trends as inorganic and organic materials. The performance of cationic starch was deteriorated, however, in the recycled white water, which resulted in the reduction of tensile index of handsheets.

Development of a Copyright Protection System for Computer Forensics (컴퓨터 포렌식을 위한 디지털 저작권 보호시스템 개발)

  • Lee, Wol-Young;Hwang, Chul
    • Journal of Korea Multimedia Society
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    • v.10 no.3
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    • pp.365-372
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    • 2007
  • The information of world is most likely to be created as digital data. These digital productions need some legal protection mechanisms or techniques because users can illegally use them. Thus many researchers are developing various techniques. Currently most techniques are focusing on the physical and chemical methods like disk inspection for taking legal evidence about production infringement. This paper has developed a computer forensics-based copyrights protection system capable of detecting and notifying disobedience facts when user uses illegally a production. Furthermore if the user infringes continually the production the system stores the infringement facts to take the legal evidence by mapping to law for intellectual property right. The technique can protect data from digital evidence manipulation or destruction.

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A Study on A Mathematical Formulation of Protection Ratio and Its Calculation for Fixed Radio Relay System with Diversity (다이버시티를 갖는 고정 무선 중계 시스템에 대한 보호비의 수학적 표현과 계산에 대한 연구)

  • Suh Kyoung-Whoan
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.17 no.4 s.107
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    • pp.358-367
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    • 2006
  • In this paper, a mathematical formulation of protection ratio and its calculation method are suggested for a radio relay system with diversity techniques. The analysis of protection ratio and its physical meaning have been performed for the space or frequency diversity system, and in particular protection ratios are reviewed in terms of the parameters of diversity improvement factor, which comprises antenna gain, separation distance between antennas, frequency and its difference between carriers, and distance. As one of simulated results, the co-channel protection ratio of 60 dB is obtained for the space diversity system regarding 6.2 GHz, 60 km, 64-QAM, and 25 m between antennas, which gives 15 dB less than the co-channel protection ratio of the non-space diversity system. In addition, the co-channel protection ratio for the frequency diversity system gives 64 dB in case of frequency offset of 0.5 GHz under the same conditions as the space diversity system, which brings about 11 dB less than the co-channel protection ratio of non-frequency diversity system. In consequency, it is interesting to note that the space diversity system is less sensitive to interference in comparison to the frequency diversity system and provides better quality of service for a given interference.

Protection Management for Guaranteed User-Driven Virtual Circuit Services in Dynamic Multi-domain Environments: Design Issues and Challenges

  • Lim, Huhnkuk
    • ETRI Journal
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    • v.37 no.2
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    • pp.369-379
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    • 2015
  • Fault management of virtualized network environments using user-driven network provisioning systems (NPSs) is crucial for guaranteeing seamless virtual network services irrespective of physical infrastructure impairment. The network service interface (NSI) of the Open Grid Forum reflects the need for a common standard management API for the reservation and provisioning of user-driven virtual circuits (VCs) across global networks. NSI-based NPSs (that is, network service agents) can be used to compose user-driven VCs for mission-critical applications in a dynamic multi-domain. In this article, we first attempt to outline the design issues and challenges faced when attempting to provide mission-critical applications using dynamic VCs with a protection that is both user-driven and trustworthy in a dynamic multi-domain environment, to motivate work in this area of research. We also survey representative works that address inter-domain VC protection and qualitatively evaluate them and current NSI against the issues and challenges.

The development of EASI-based multi-path analysis code for nuclear security system with variability extension

  • Andiwijayakusuma, Dinan;Setiadipura, Topan;Purqon, Acep;Su'ud, Zaki
    • Nuclear Engineering and Technology
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    • v.54 no.10
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    • pp.3604-3613
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    • 2022
  • The Physical Protection System (PPS) plays an important role and must effectively deal with various adversary attacks in nuclear security. In specific single adversary path scenarios, we can calculate the PPS effectiveness by EASI (Estimated Adversary Sequence Interruption) through Probability of Interruption (PI) calculation. EASI uses a single value of the probability of detection (PD) and the probability of alarm communications (PC) in the PPS. In this study, we develop a multi-path analysis code based on EASI to evaluate the effectiveness of PPS. Our quantification method for PI considers the variability and uncertainty of PD and PC value by Monte Carlo simulation. We converted the 2-D scheme of the nuclear facility into an Adversary Sequence Diagram (ASD). We used ASD to find the adversary path with the lowest probability of interruption as the most vulnerable paths (MVP). We examined a hypothetical facility (Hypothetical National Nuclear Research Facility - HNNRF) to confirm our code compared with EASI. The results show that implementing the variability extension can estimate the PI value and its associated uncertainty. The multi-path analysis code allows the analyst to make it easier to assess PPS with more extensive facilities with more complex adversary paths. However, the variability of the PD value in each protection element allows a significant decrease in the PI value. The possibility of this decrease needs to be an important concern for PPS designers to determine the PD value correctly or set a higher standard for PPS performance that remains reliable.