• Title/Summary/Keyword: Nuclear data

Search Result 3,721, Processing Time 0.03 seconds

Recent Insights from the International Common-Cause Failure Data Exchange Project

  • Kreuser, Albert;Johanson, Gunnar
    • Nuclear Engineering and Technology
    • /
    • v.49 no.2
    • /
    • pp.327-334
    • /
    • 2017
  • Common-cause failure (CCF) events can significantly impact the availability of safety systems of nuclear power plants. For this reason, the International Common Cause Data Exchange (ICDE) project was initiated by several countries in 1994. Since 1997 it has been operated within the Organisation for Economic Co-operation and Development (OECD)/Nuclear Energy Agency (NEA) framework and has successfully been operated over six consecutive terms (the current term being 2015-2017). The ICDE project allows multiple countries to collaborate and exchange CCF data to enhance the quality of risk analyses, which include CCF modeling. As CCF events are typically rare, most countries do not experience enough CCF events to perform meaningful analyses. Data combined from several countries, however, have yielded sufficient data for more rigorous analyses. The ICDE project has meanwhile published 11 reports on the collection and analysis of CCF events of specific component types (centrifugal pumps, emergency diesel generators, motor operated valves, safety and relief valves, check valves, circuit breakers, level measurement, control rod drive assemblies, and heat exchangers) and two topical reports. This paper presents recent activities and lessons learnt from the data collection and the results of topical analysis on emergency diesel generator CCF impacting entire exposed population.

HUMAN ERRORS DURING THE SIMULATIONS OF AN SGTR SCENARIO: APPLICATION OF THE HERA SYSTEM

  • Jung, Won-Dea;Whaley, April M.;Hallbert, Bruce P.
    • Nuclear Engineering and Technology
    • /
    • v.41 no.10
    • /
    • pp.1361-1374
    • /
    • 2009
  • Due to the need of data for a Human Reliability Analysis (HRA), a number of data collection efforts have been undertaken in several different organizations. As a part of this effort, a human error analysis that focused on a set of simulator records on a Steam Generator Tube Rupture (SGTR) scenario was performed by using the Human Event Repository and Analysis (HERA) system. This paper summarizes the process and results of the HERA analysis, including discussions about the usability of the HERA system for a human error analysis of simulator data. Five simulated records of an SGTR scenario were analyzed with the HERA analysis process in order to scrutinize the causes and mechanisms of the human related events. From this study, the authors confirmed that the HERA was a serviceable system that can analyze human performance qualitatively from simulator data. It was possible to identify the human related events in the simulator data that affected the system safety not only negatively but also positively. It was also possible to scrutinize the Performance Shaping Factors (PSFs) and the relevant contributory factors with regard to each identified human event.

A Disk-based Archival Storage System Using the EOS Erasure Coding Implementation for the ALICE Experiment at the CERN LHC

  • Ahn, Sang Un;Betev, Latchezar;Bonfillou, Eric;Han, Heejune;Kim, Jeongheon;Lee, Seung Hee;Panzer-Steindel, Bernd;Peters, Andreas-Joachim;Yoon, Heejun
    • Journal of Information Science Theory and Practice
    • /
    • v.10 no.spc
    • /
    • pp.56-65
    • /
    • 2022
  • Korea Institute of Science and Technology Information (KISTI) is a Worldwide LHC Computing Grid (WLCG) Tier-1 center mandated to preserve raw data produced from A Large Ion Collider Experiment (ALICE) experiment using the world's largest particle accelerator, the Large Hadron Collider (LHC) at European Organization for Nuclear Research (CERN). Physical medium used widely for long-term data preservation is tape, thanks to its reliability and least price per capacity compared to other media such as optical disk, hard disk, and solid-state disk. However, decreasing numbers of manufacturers for both tape drives and cartridges, and patent disputes among them escalated risk of market. As alternative to tape-based data preservation strategy, we proposed disk-only erasure-coded archival storage system, Custodial Disk Storage (CDS), powered by Exascale Open Storage (EOS), an open-source storage management software developed by CERN. CDS system consists of 18 high density Just-Bunch-Of-Disks (JBOD) enclosures attached to 9 servers through 12 Gbps Serial Attached SCSI (SAS) Host Bus Adapter (HBA) interfaces via multiple paths for redundancy and multiplexing. For data protection, we introduced Reed-Solomon (RS) (16, 4) Erasure Coding (EC) layout, where the number of data and parity blocks are 12 and 4 respectively, which gives the annual data loss probability equivalent to 5×10-14. In this paper, we discuss CDS system design based on JBOD products, performance limitations, and data protection strategy accommodating EOS EC implementation. We present CDS operations for ALICE experiment and long-term power consumption measurement.

Data Management and Communication Networks for Man-Machine Interface System in Korea Advanced Liquid MEtal Reactor : Its Functionality and Design Requirements

  • Cha, Kyung-Ho;Park, Gun-Ok;Suh, Sang-Moon;Kim, Jang-Yeol;Kwon, Kee-Choon
    • Proceedings of the Korean Nuclear Society Conference
    • /
    • 1998.05a
    • /
    • pp.291-296
    • /
    • 1998
  • The DAta management and Communication NETworks (DACONET), Which it is designed as a subsystem for Man-Machine Interface System of Korea Advanced LIquid MEtal Reactor(KALIMER MMIS) and advanced design concept is approached, is described. The DACONET has its roles of providing the real-time data transmission and communication paths between MMIS systems, providing the quality data for protection, monitoring and control of KALIMER and logging the static and dynamic behavioral data during KALIMER operation. The DACONET is characterised as the distributed real-time system architecture with high performance, Future direction, in which advanced technology is being continually applied to Man-Machine interface System Development of Nuclear Power Plants, will be considered for designing data management and communication networks of KALIMER MMIS

  • PDF