• Journal of Energy Engineering
• /
• v.22 no.3
• /
• pp.283-286
• /
• 2013

The existing nuclear power plants have been often redesigned by increasing or decreasing electrical power without changing design concept by the request of utility, economic factors or other factors. When the cost of power plant equipment redesigned by changing reactor power and electrical power is estimated, if its quotation is not available in the market place, cost scaling factor(CSF) applies to the cost of existing plant equipment and then the new-designed equipment cost can be calculated. In this paper, we review CSFs according to plant capacity change cases in United State DOE, EPRI, ABB, SWEC and introduce the results applied to Korean PWR 1000MWe and 1400MWe.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.23 no.5
• /
• pp.279-288
• /
• 2019

Safety-related cabinets and their electrical parts, such as relays and switches in nuclear power plants, should maintain continuous functioning, as well as structural safety according to the nuclear regulatory guidelines. Generally, an electrical part is qualified if its functioning is maintained without abnormality during excitement by motion compatible with the test response spectrum, which is larger than its in-cabinet response spectrum (ICRS). ICRS can be determined by shake-table test or dynamic analysis. Since existing cabinets in use can hardly be stopped and moved, dynamic analysis is preferred over shake-table test in determining ICRS. The simple method, suggested by the Electric Power Research Institute (EPRI) to determine ICRS, yields conservative or non-conservative results from time to time. In order to determine that the ICRS is better than EPRI method in a simple way, Ritz method considering global and local plate behaviors was suggested by Gupta et al. In this paper, the Ritz method is modified in order to consider the rocking and frame behaviors simultaneously, and it is applied to a simple numerical example for verification. ICRS is determined by Ritz method and compared with the results by finite element method (FEM). Based on this numerical example, recommendations for using Ritz method are suggested.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.34 no.3
• /
• pp.537-552
• /
• 2024

Domestic nuclear power plants operate under the establishment of the "Information System Security Regulations" in accordance with the Nuclear Safety Act, introducing and implementing a cybersecurity system that encompasses organizational structure as well as technical, operational, and managerial security measures for assets. Despite attempts such as phased approaches and alternative measures for physical protection systems, the reduction in managed items has not been achieved, leading to an increased burden on security capabilities due to limited manpower at the site. In the main text, an analysis is conducted on Type A1 assets performing nuclear safety functions using Maintenance Rules (MR) and EPRI Technical Assessment Methodology (TAM) from both a maintenance perspective and considering device characteristics. Through this analysis, approaches to re-evaluate the impact of cyber intrusions on asset functionality are proposed.

• Proceedings of the KACD Conference
• /
• 2001.11a
• /
• pp.577-577
• /
• 2001

The lastest concepts in bonding are "total etch", in which both enamel and dentin are etched with an acid to remove the smear layers, and "wet dentin" in which the dentin is not blown dry but left moist before application of the bonding primer. Ideally, the application of a bonding agent to tooth structure should be insensitive to minor contamination from oral fluids. Clinically contaminations such as saliva, gingival fluid, blood and handpiece lubricant are often encountered by dentists during preparation of a restoration. The aim of this study was to evaluate the effect of contamination by hem-ostatic agents on shear bond strength of compomer restorations. One hundred and ten extracted human maxillary and mandibular molar teeth were collected. The teeth were cleaned from soft tissue remnant and debris and stored in physiologic solution until they were used. Small flat area on dentin of the buccal surface were wet ground serially with 400, 800 and 1200 abrasive paper on automatic polishing machine. The teeth were randomly divided into 11 groups. Each group was conditioned as follows: Group 1 : Dentin surface was not etched and not contaminated by hemostatic agents. Group2 : Dentin surface was not etched but was contaminated by Astringedent (Ultradent product Inc., Utah, U.S.A.). Group3 : Dentin surface was not etched but was contaminated by Bosmin (Jeil Phann, Korea.). Group4 : Dentin surface was not etched but was contaminated by Epri-dent (Epr Industries, NJ, U.S.A.). Group5: Dentin surface was etched and not contaminated by hemostatic agents. Group 6 : Dentin surface was etched and contaminated by Astringedent. Group7 : Dentin surface was etched and contaminated by Bosmin. Group8 : Dentin surface was etched and contaminated by Epri-dent. Group9 : Dentin surface was contaminated by Astringedent. The contaminated surface was rinsed by water and dried by compressed air. Group10 : Dentin surface was contaminated by Bosmin. The contaminated surface was rinsed by water aud dried by compresfed air. Group 11 : Dentin surface was contaminated by Epri-dent. The contaminated surface was rinsed by water and dried by compresfed air. After surface conditioning, F2000 was applicated on the conditoned dentin surface. The teeth were thermocycled in distilled water at $5^{\circ}C\;and\;55^{\circ}C$ for 1000 cycles. The samples were placed on the binder with the bonded compomer-dentin interface parallel to the lmife-edge shearing rod of the Universal testing machine(Zwick 020, Germany) running at a cross head speed of 1.0mmimin. There were no significant differences in shear bond strength between groups 1 and group 3 and 4, but group 2 showed significant decrease in shear bond strength compared with group 1. There were no significant differences in shear bond strength between group 5 and group 7 and 8, but group 6 showed significant decrease in shear bond strength compared with group 5. There were no significant differences in shear bond strength between group 5 and group 9, 10 and 11.

• Proceedings of the KWS Conference
• /
• 2004.05a
• /
• pp.308-310
• /
• 2004

1980년대 초 미국의 비등형 경수로(Boiling Water Reactor : BWR) 원자력발전소 배관계통의 입계 응력 부식 균열(Inter-Granular Stress Corrosion Crack) 검사 결과 및 미국 EPRI(Electric Power Research Institute)에서 실시한 round robin test 결과에서 기존 초음파 검사 방법의 실효성에 많은 문제점이 제기 되었다. (중략)

• Journal of Energy Engineering
• /
• v.22 no.4
• /
• pp.386-393
• /
• 2013

An feasibility analysis is performed for the tidal current power generation with the examination of the sea water speed distribution at Pungdo. In this analysis, the water speed distribution which is the key issue was obtained from the actual speed distribution data and results in "the annual current tidal power". Due to the lack of cost information, we applied EPRI data from the internet site instead of the actual information. The result could be used as a base data for the construction of current tidal power plant in the near future. And it is expected to provides good data for the Energy policy.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.38 no.11
• /
• pp.1257-1264
• /
• 2014

Efforts are presently underway for developing an optimal design methodology for GEN-IV nuclear reactors based on target failure probabilities. A typical example is the system-based code, in which the results are represented in the form of partial safety factors (PSFs). Thus, a PSF is one of the crucial elements in either component design or integrity assessment based on target failure probabilities during the operation period. In the present study, a procedure for calculating the PSF of a circumferential through-wall cracked pipe based on the elastic-plastic crack initiation criterion is established, in which the importance of each input variable is assessed. Elastic-plastic J-integrals are calculated using the GE/EPRI and reference stress methods, and the PSF values are calculated using both first- and second-order reliability methods. Moreover, the effect of statistical distributions of assessment variables on the PSF is also evaluated.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.18 no.3
• /
• pp.65-73
• /
• 2004

The bolier systems of coal fired power plants are large, non-linear systems with numerous interactions between its component parts. In the analysis of such complex systems, dynamic simulation is recognized as a powerful method of keeping track of the myriad of interactions. The boiler system consists of air/gas system and water/steam system. Due to recent reinforcement of environmental regulation on pollutant discharge and requirements of design validation on properites of boiler, the commercial programs are used for the analysis of boiler system. This paper addressed to the development of model using MMS(Modular Modeling System) developed by EPRI(Electric Power Research Institute) as the simulation tool. The developed model using MMS is tested for the design and local data on boiler combustion system of korea standard coal fired power plant boiler. The simulation results show that the developed model well reproduces responses of the combustion system with less than ${\pm}$5% error under steady state and transient state conditions. The developed model for analysis of the combustion system in this paper is general and applicable to any type of coal fired power plant.

• Journal of Energy Engineering
• /
• v.2 no.1
• /
• pp.28-37
• /
• 1993

This paper describes the development of a dynamic model of 1,000 MW$\_$e/ nuclear power plant including its local and integrated control system. The model was constructed using the Modular Modeling System (MMS) developed by the Electric Power Research Institute (EPRI) to provide an efficient, economical and user-friendly computer code for use in the analysis of the dynamic performance of nuclear and fossil power plants in conjunction with the Advanced Continuous Simulation Language (ACSL). Steady state for full load and transient results for turbine power step changes of loft are presented in this paper. The model includes most major components of a 1,000 MW$\_$e/ nuclear power plant and it can readily be modified to simulate a specific power plant. This procedure greatly reduces the analysis and modeling efforts involved in dynamic simulation of power plants and increases confidence in the analysis results.

• Transactions of the Korean Society of Pressure Vessels and Piping
• /
• v.15 no.1
• /
• pp.28-32
• /
• 2019

In nuclear power plant operation and spent fuel canisters, it is necessary to provide a sound technical basis for the safety and security of long-term operation and storage respectively. Recently, the peening technology is being discussed and the technology will be adopted to ASME Section III, Division 1, Subsection NX (2019 Edition). The peening is prohibited in current edition, but it will be approved in 2019 Edition and adopted. However, Surface stress improvement techniques such as the peening is used to mitigate SCC susceptible in operating nuclear plants. Although the peening will be approved to ASME CODE, there are no performance criteria listed in the 2019 edition. The Korean International Working Group (KIWG) formed a new Task Group named "Advanced Surface Stress Improved Technology". The task group will develop a CODE CASE to address PWSCC(Primary Water Stress Corrosion Cracking) and CISCC(Chloride Induced Stress Corrosion Cracking) for new ASME Section III components. TG-ASSIT was started to make peening performance criteria for ASME Section III (new fabrication) applications. The objective of TG-ASSIT is to gain consensus among the relevant Code groups that requirements/mitigation have been met.