• Steel and Composite Structures
• /
• v.37 no.5
• /
• pp.589-603
• /
• 2020

This paper presents an investigation of the thermal performance of composite floor slabs with profiled steel decking exposed to fire effects from floor. A detailed finite-element model has been developed by representing the concrete slab with steel decking under of it and steel beam both steel parts protected by intumescent coating. Although this type of floor systems offers a better fire resistance, passive fire protection materials should be applied when a higher fire resistance is desired. Moreover, fire exposed side is so crucial for composite slab systems as the total fire behaviour of the floor system changes dramatically. When the fire attack from steel parts, the temperature rises rapidly resulting in a sudden decrease on the strength of the beam and decking. Herein this paper, the fire attack side is assumed from the face of the concrete floor (top of the concrete assembly). Therefore, the heat is transferred through concrete to the steel decking and reaching finally to the steel beam both protected by intumescent coating. In this work, the numerical model has been established to predict the heat transfer performance including material properties such as thermal conductivity, specific heat and dry film thickness of intumescent coating. The developed numerical model has been divided into different layers to understand the sensitivity of steel temperature to the number of layers of intumescent coating. Results show that the protected composite floors offer a higher fire resistance as the temperature of the steel section remains below 60℃ even after 60-minute Standard (ISO) fire and Fast fire exposure. Obtaining lower temperatures in steel due to the great fire performance of the concrete itself results in lesser reductions of strength and stiffness hence, lesser deflections.

• Journal of radiological science and technology
• /
• v.31 no.4
• /
• pp.347-353
• /
• 2008

This study is to prepare an evaluation standard about personal information protection and security management of a medical institution and to build up a grade standard of evaluation in PACS environment. We built up evaluation index based on 10 detailed items in four big categories (political security, technical security, data management security and physical security) by referring to ISO17799 (BS 7799), HIPPA (Health Insurance and Portability and Accountability Act of 1996) and domestic medical law. We have investigated at the thirty places where medical facility with the extracted security criteria and security evaluation index. Average score of physical security list, one of the big categories, was 18.5/20 (93%) at all medical institutions. Political security score was 18.5/30 (62%), data management security score was 12/20 (60%) and technical security score was 17.5/30 (58%). Therefore, security evaluation score was average 67 in 30 general hospitals, which was 4th level. The results showed that it is necessary to establish evaluation and management standard about personal information protection and security consciousness which are weak in PACS environment.

• Journal of the Korean Society of Safety
• /
• v.35 no.1
• /
• pp.87-96
• /
• 2020

The purpose of this paper is to develop a fire HRA (Human Reliability Analysis) procedure for full power operation of domestic NPPs (Nuclear Power Plants). For the development of fire HRA procedure, the recent research results of NUREG-1921 in an effort to meet the requirements of the ASME/ANS PRA Standard were reviewed. The K-HRA method, a standard method for HRA of a domestic level 1 PSA (Probabilistic Safety Assessment) and fire related procedures in domestic NPPs were reviewed. Based on the review, a procedure for the fire HRA required for a domestic fire PSA based on the K-HRA method was developed. To this end, HRA issues such as new operator actions required in the event of a fire and complexity of fire situations were considered. Based on the four kinds of HFE (Human Failure Event) developed for a fire HRA in this research, a qualitative analysis such as feasibility evaluation was suggested. And also a quantitative analysis process which consists of screening analysis and detailed analysis was proposed. For the qualitative analysis, a screening analysis by NUREG-1921 was used. In this research, the screening criteria for the screening analysis was modified to reduce vague description and to reflect recent experimental results. For a detailed analysis, the K-HRA method and scoping analysis by NUREG-1921 were adopted. To apply K-HRA to fire HRA for quantification, efforts to modify PSFs (Performance Shaping Factors) of K-HRA to reflect fire situation and effects were made. For example, an absence of STA (Shift Technical Advisor) to command a fire brigade at a fire area is considered and the absence time should be reflected for a HEP (Human Error Probability) quantification. Based on the fire HRA procedure developed in this paper, a case study for HEP quantification such as a screening analysis and detailed analysis with the modified K-HRA was performed. It is expected that the HRA procedure suggested in this paper will be utilized for fire PSA for domestic NPPs as it is the first attempt to establish an HRA process considering fire effects.

• Fire Science and Engineering
• /
• v.29 no.4
• /
• pp.26-32
• /
• 2015

Carbon dioxide principally extinguishes fires by smothering, but an acceptable amount of extinguishing agent is needed. To assure the performance of carbon dioxide systems in Korea, computer programs certified by NEMA are being applied in system design. But the design errors can occur because the geometry of a model test facility is not the same as that of the actual fire area. Since the discharge rate tends to vary considerably with the flow pattern in a pipe, an on-site discharge test is necessary to ensure the performance of the system, especially with low pressure carbon dioxide. Technical standards for carbon dioxide systems do not give detailed guidelines for discharge tests at present. Based on comparative analysis of standards and practical tests, this paper suggests a methodology for on-site discharge tests.

• Journal of Engineering Education Research
• /
• v.12 no.2
• /
• pp.24-35
• /
• 2009

This study was conducted to establish a principle on the fields of National Technical Qualification(NTQ), and aimed at developing criteria on requirements of the qualification that will be managed as the national technical qualification. In order to achieve the objective of the study, we examined the directions of setting the Jurisdiction of national technical qualification through role assignment between the state and private sectors. Also, we reviewed related documents, conducted Delphi survey, consulted the expert group and had an interview session for this study. There are five criteria of the jurisdiction of NTQ presented as follows. First is the field which disturbs social orders or has possibility of harming the good public morals; second, the field that requires high standards of ethics or is directly linked to life, health and safety of the public; third, the field which requires national attention for training of manpower as it is an area that is difficult for private sector to approach or it requires national management; fourth, the field which requires repair or maintenance of resources of traditional culture but is difficult for the private sector to have an access to and fifth, the field where it needs to protect the interest of the nation in the inter-nation relationships. The concrete and detailed standard on the five criteria is also presented in the study.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.3
• /
• pp.671-678
• /
• 2021

In a previous study, technology protection levels were set on a qualitative basis. That study lacked quantitative standards, so here, we conduct a study to complement the previous study and to present an objective standard. This paper provides a method of setting a technical protection level that applies statistical analysis. To set the technology protection level, statistical analysis of six technical survey items is performed first. Second, the technical survey items are analyzed by AHP to quantify the opinions of experts in order to derive weights for each technical survey item. Finally, by using the normal distribution scatter map and median calculation method, the technology protection level is selected in three stages using the final detailed factor technology score reflecting the weight. The technology protection level methodology developed through this study is the first methodology with objectivity that can evaluate defense technology by level. If this methodology is applied in practice, it is believed that it will provide a scientific and quantitative technology value judgment criterion when setting the technology protection level in the future.

• Journal of the Korea Society of Computer and Information
• /
• v.18 no.9
• /
• pp.63-70
• /
• 2013

The multimedia data of game affects the immersion of the game depending on its quality. It is difficult to design the evaluation criteria of artistic quality of the data. But, in a technical point of view, it is possible to evaluate its quality. Thus, the design of evaluation standard can ensure the reliability and objectivity of quality. However, multimedia data quality evaluation metrics had not yet been designed. Therefore, in this study, we extracted quality evaluation elements of Game Multimedia Data, and verified the reliability of the elements. And we defined detailed evaluation items of each element, developed Multimedia Data Quality Evaluation Metrics. We expect that the results of this study will serve as a guide in the development of high-quality games, have a positive impact on the growth of the game industry.

• Journal of the military operations research society of Korea
• /
• v.36 no.1
• /
• pp.29-38
• /
• 2010

In Korea weapon system acquisition processes, it's required a cost estimation report obtained from a commercial cost model. The PRICE model is generally used as a cost estimation model in Korea. However, the model uses American historical R&D data and it's output cost component is different from our cost component of defense accounting system. Also, we found that estimating results show about 10% of difference when we comparing with actual costs in 44 finished weapon acquisition projects. There are some limitations in calibration to increase an accuracy of the PRICE model because it's difficult obtain good real input data, detailed cost and technical data in low level WBS. So, only 8% of the defense R&D projects are calibrated and validation of calibration results is more difficult. Therefore, we studied the standard calibration process and performed the calibration about the MCPLXS/E parameters of the PRICE model based on actual cost data. In order to obtain a good calculation result, we collected the actual material costs from the defense industry companies. Our results can be used for an reference in similar weapon system R&D and production cost estimation cases.

• Journal of the Korean Society of Safety
• /
• v.25 no.6
• /
• pp.53-59
• /
• 2010

A fatigue damage caused by cyclic load is considered as one of the important failure mechanisms that threaten the integrity of structures and components in a nuclear power plant. In ASME code section III NB, the fatigue analysis procedure and standard S-N curves for the class 1 components are described and these criteria should be met at the design step of components. As the current ASME S-N curves are based on the very conservative assumptions such as a local stress concentration effect, immoderate transient frequencies and a constant Young's modulus, however, they can not precisely address the fatigue behavior of components. In order to find out the technical solution for these problems, a number of researches and discussion have been carried out continuously at home and abroad over the decades. In this study, detailed fatigue analyses for DVI nozzle with various mesh density of finite elements were performed to evaluate effect of stress concentration factors on the fatigue analysis procedure and the excessive conservatism of stress concentration factors are confirmed through the analysis results.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2002.05a
• /
• pp.53-57
• /
• 2002

Quality evaluation must be more developed in order to offer the sufficient information for producer, distribution centers buyer, consumer. There are many parameters which influence the rice quality and cooked rice. It is difficult to evaluate the quality of rice and cooked rice by only some parameters. In the case of rice quality evaluation in Korea, physicochemical inspection is performed by examining the minimum and maximum limits of brown rice recovery, moisture content, damaged kernel, and colored kernel as inspection standard. Marketing standard of rice defines the limits of perfect, white core and belly, colored, damaged kernels, and broken rice, classifying into special, excellent, and normal grades. As a research direction for the development of rice quality evaluation, establishment as parts of technical field, must be further developed as follows : more detailed measure of characters, search of unknown taste-related components, creation and grade classification of quality evaluation factors at each management stages of treatment after harvesting, evaluation as food material as well as cooking rice, method development for simple evaluation and establishment of equation for palatability. In the side of policy, the following concerns must be conducted: price discrimination in conformity to rice cultivar and grade under the basis of qualify evaluation method developed, fixation of head rice branding, and introduction of low temperature circulation.