• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.20 no.6
• /
• pp.127-146
• /
• 2010

This report has continuously improved in Information Security Level of Information Communication Service Companies which are applicable to Information Security Safety Inspection System. Also, it presents a decided methodology after verified propriety and considered the pre-research or expropriation by being developed the way of Information Security Safety Result Measurement. Management territory weighted value was established and it was given according to the point of view and the strategy target and the and outcome index to consider overall to a measurement item. Accordingly, an outome to the Information Security Check Service is analyzed by this paper and measurement model and oucome analysis methodology are shown with this, and gives help to analyze an outcome. Also it make sure the the substantial information security check service will be accomplished, prevent a maintenance accident beforehand and improve an enterprise outcome independently by institutional system performance securement and enterprise.g corporate performance.

• Transactions of the Korean Society of Pressure Vessels and Piping
• /
• v.17 no.1
• /
• pp.18-27
• /
• 2021

This study aims to develop an improved evaluation technology for assessing CANDU-6 safety. For this purpose, the multiple steam generator tube rupture (mSGTR) followed by an unmitigated station blackout (SBO) in a CANDU-6 plant was selected as a hypothetical event scenario and the analysis model to evaluate the plant responses was envisioned into the MARS-KS input model. The model includes logic models for controlling the pressure and inventory of the primary heat transport system (PHTS) decreasing due to the u-tubes' rupture, as well as the main features of PHTS with a simplified model for the horizontal fuel channels, the secondary heat transport system including the shell side of steam generators, feedwater and main steam line, and moderator system. A steady state condition was successfully achieved to confirm the stable convergence of the key parameters. Until the turbine trip, the fuel channels were adequately cooled by forced circulation of coolant and supply of main feedwater. However, due to the continuous reduction of PHTS pressure and inventory, the reactor and turbine were shut down and the thermal-hydraulic behaviors between intact and broken loops got asymmetric. Furthermore, as the conditions of low-flow coolant and high void fraction in the broken loop persisted, leading to degradation of decay heat removal, it was evaluated that the peak cladding temperature (PCT) exceeded the limit criteria for ensuring nuclear fuel integrity. This study is expected to provide the technical bases to the accident management strategy for transient conditions with multiple events.

• Journal of the Society of Disaster Information
• /
• v.19 no.2
• /
• pp.241-253
• /
• 2023

Purpose: The purpose of this study is to introduce the structure and functions of an application developed for enhancing risk knowledge/perception, called KNOWRISK, and to identify and determine problems and requirements based on the usability evaluation results of the application. Method: The evaluation was conducted using the Mobile App Rating Scale (MARS) with a sample of 43 application users and related experts. Result: The application received a satisfactory evaluation score with an overall average of 4.074 points, and there was no significant difference in evaluation scores between experts and users. The highest score was for ease of use at 4.47, while the lowest score was for cost payment usage at 2.88. Conclusion: The results of this study suggest that efforts to increase risk knowledge and promote safe behavior using a mobile application can be an effective and efficient strategy for preventing industrial accidents and enhancing safety management.

• Transactions of the Korean Society of Pressure Vessels and Piping
• /
• v.18 no.2
• /
• pp.37-42
• /
• 2022

An influence analysis on multiple steam generator tube rupture (mSGTR) followed by an unmitigated station blackout is performed to compare the plant responses according to the number of ruptured u-tubes under the assumption of a total of 10 ruptured u-tubes. In all calculation cases, the transient behaviour of major thermal-hydraulic parameters, such as the discharge flow rate through the ruptured u-tubes, reactor header pressure, and void fraction in the fuel channels is found to be overall similar to that of the base case having a single SG with 10 u-tubes ruptured. Additionally, as the conditions of low-flow coolant with high void fraction in the broken loop continued, causing the degradation of decay heat removal, the peak cladding temperature (PCT) would be expected to exceed the limit criteria for ensuring nuclear fuel integrity. However, despite the same total number of ruptured u-tubes, because of the different connection configuration between the SG and pressurizer, a difference is foud in time between the pressurizer low-level signal and reactor header low-pressure signal, affecting the time to trip the reactor and to reach the PCT limit. The present study is expected to provide the technical basis for the accident management strategy for mSGTR transient conditions of CANDU-6 plants.

• Nuclear Engineering and Technology
• /
• v.56 no.1
• /
• pp.9-18
• /
• 2024

In-vessel retention through external reactor vessel cooling (IVR-ERVC) is a severe accident management (SAM) strategy that has been adopted and used in many nuclear reactors such as AP1000, APR1400, and light water reactor etc. Some reactor accidents have raised concerns about nuclear reactors among residents, leading to a decrease in residents' acceptability and many studies on SAM are being conducted. Experiments on IVR-ERVC are almost impossible due to its specificity, so fluid characteristics are analyzed through BALI experiments with similar condition. In this study, computational fluid dynamics (CFD) via Reynolds-averaged Navier-Stokes (RANS) and large eddy simulation (LES) for BALI experiments were performed. Steady-state CFD analysis was performed on three turbulence models, and SST k-ω model was in good agreement with the experimental measurement temperature within the maximum error range of 1.9%. LES CFD analysis was performed based on the RANS analysis results and it was confirmed that the temperature and wall heat flux for depth was consistent within an error range of 1.0% with BALI experiment. The LES CFD analysis results were compared with those of the Lagrangian-based solver. LES matched the temperature distribution better than SOPHIA, but SOPHIA calculated the position of boundary between stratified layer and convective layer more accurately. On the other hand, Lagrangian-based solver predicted several small eddy behaviors of the convective layer and LES predicted large vortex behavior. The vibration characteristics near the cooling part of the BALI experimental device were confirmed through Fast Fourier Transform (FFT) investigation. It was found that the power spectral density for pressure at least 10 times higher near the side cooling than near the top cooling.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.6
• /
• pp.596-608
• /
• 2017

In 2002, the government arranged an institutional strategy to make it possible for a consumers to make a claim for damages caused by product defects against a business that produces and sells a product by enforcing the Product Liability Law(hereinafter referred to as 'PL'). On the other hand, due to the recent humidifier sterilizer accident, approximately 12 cases of related bills, such as a revised bill for the product liability law, have been proposed to the National Assembly at present in an effort to introduce the group action system and punitive compensation system for the purpose of the strengthening of the corporate product liability, and consumer damage relief. Ironically, as much as 62.6% of small & medium businesses, which are actual interested parties to this bill, are unaware of this. Many companies are responding to PL with the rationalization of document preparation & storage, clarification of responsibility relations with related business operators, and PL insurance policy purchase, or securing compensation funds as a means of Product Liability Defense(PLD), but the methods of preparation such as this leave much room for limits on the considerations of product design and product safety. This paper presents the individual management system model with more focus on product safety by looking into the clear concept of PL and the countermeasures against it, grasping the relevance between the PL system and individual management system, and integrating the PL response system in preparation for the PL. It is hoped that the result of this research objective will be evaluated as a rational countermeasure for small & medium businesses to respond effectively to the PL.

• Journal of Korean Society of Transportation
• /
• v.34 no.1
• /
• pp.68-80
• /
• 2016

Interest in freeway truck traffic has increased largely due to greater safety concerns regarding truck-related crashes. The negative interactions between slow-moving trucks and other vehicles are a primary cause of hazardous conditions, which lead to crashes with larger speed variations. To improve operational efficiency and safety, providing a climbing lane that separates slow-moving trucks from higher performance vehicles is frequently considered when upgrading geometrics. This study developed an operations strategy for freeway climbing lanes based on traffic conditions in real time. To consider traffic safety when designing a dynamic strategy to determine whether a climbing lane is closed or open, various factors, including the level of service (LOS) and the percentage of trucks, are investigated through microscopic simulations. A microscopic traffic simulator, VISSIM, was used to simulate freeway traffic streams and collect vehicle-maneuvering data. Additionally, an external application program interface, VISSIM's COM-interface, was used to implement the proposed climbing lane operations strategies. Surrogate safety measures (SSM), including the frequency of rear-end conflicts and, were used to quantitatively evaluate the traffic safety using an analysis of individual vehicle trajectories obtained from VISSIM simulations with various operations scenarios. It is expected that the proposed algorithm can be the backbone for operating the climbing lane in real time for safer traffic management.

• Journal of the Korea Convergence Society
• /
• v.6 no.4
• /
• pp.139-146
• /
• 2015

WSN has been utilized in various directions from basic infrastructure of environment composition to business models including corporate inventory, production and distribution management. However, as energy organizations' private information, which should be protected safely, has been integrated with ICT such as WSN to be informatization, it is placed at potential risk of leaking out with ease. Accordingly, it is time to need secure sensor node deployment strategies for stable enterprise business. Establishment of fragmentary security enhancement strategies without considering energy organizations' security status has a great effect on energy organizations' business sustainability in the event of a security accident. However, most of the existing security level evaluation models for diagnosing energy organizations' security use technology-centered measurement methods, and there are very insufficient studies on managerial and environmental factors. Therefore, this study would like to diagnose energy organizations' security and to look into how to accordingly establish strategies for planning secure sensor node deployment strategies.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.15 no.4
• /
• pp.391-402
• /
• 2017

The Korea Radioactive Waste Agency (KORAD) has developed a concrete cask for the dry storage of spent nuclear fuel that has been generated by domestic light-water reactors. During long-term storage of spent nuclear fuel in concrete casks kept in dry conditions, the integrity of the concrete cask and spent nuclear fuel must be maintained. In addition, the radiation dose rate must not exceed the storage facility's design standards. A suitable shielding design for radiation protection must be in place for the dry storage facilities of spent nuclear fuel under normal and accident conditions. Evaluation results show that the appropriate distance to the annual dose rate of 0.25 mSv for ordinary citizens is approximately 230 m. For a $2{\times}10$ arrangement within storage facilities, rollover accidents are assumed to have occurred while transferring one additional storage cask, with the bottom of the cask facing the controlled area boundary. The dose rates of 12.81 and 1.28 mSv were calculated at 100 m and 230 m from the outermost cask in the $2{\times}10$ arrangement. Therefore, a spent nuclear fuel concrete cask and storage facilities maintain radiological safety if the distance to the appropriately assessed controlled area boundary is ensured. In the future, the results of this study will be useful for the design and operation of nuclear power plant on-site storage or intermediate storage facilities based on the spent fuel management strategy.

• Korean Journal of Childcare and Education
• /
• v.12 no.1
• /
• pp.57-81
• /
• 2016

The purpose of this study was to find out the feature of children's play according to a player number restriction rule in the free choice activities. And it is expected that the result of this study will contribute to improving the management of free choice activities. The participants of this study were a homeroom teacher, professor as a co-researcher and 25 4-year-old children of a private kindergarten. The data were collected by observation, children interview and reflective journal of the teacher from July to October in 2014. The results indicated that the children were stressed out with using name cards for presenting center selection, showed overcompetitive behaviors, and frequently violated the rules. The researchers found that the restriction rule had some dysfunctions, which were interferences of moral development, social-emotional development, self-regulation development, preventing safety-accident and free choice behavior. The researcher as a teacher abandoned the player number restriction rule, and observed the children's play. As a result, children's self-regulation abilities on physical space, play and conflicts improved and the teacher changed her strategy when managing free choice activities. Based on the results, the needs of various restriction rules and appropriate methods for applying the rules in free choice activities were further discussed.