• Journal of the Korean Society of Systems Engineering
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• v.14 no.2
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• pp.24-32
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• 2018

System Complexity one of the most common cause failure of the projects, it leads to a lack of understanding about the functions of the system. Hence, the model is developed for communication and furthermore modeling help analysis, design, and understanding of the system. On the other hand, the text-based specification is useful and easy to develop but is difficult to visualize the physical composition, structure, and behaviour or data exchange of the system. Therefore, it is necessary to transform system description into a diagram which clearly depicts the behaviour of the system as well as the interaction between components. According to the International Atomic Energy Agency (IAEA) Safety Glossary, The safety system is a system important to safety, provided to ensure the safe shutdown of the reactor or the residual heat removal from the reactor core, or to limit the consequences of anticipated operational occurrences and design basis accidents. Core Protection Calculator System (CPCS) in Advanced Power Reactor 1400 (APR 1400) Nuclear Power Plant is a safety critical system. CPCS was developed using systems engineering method focusing on Departure from Nuclear Boiling Ratio (DNBR) calculation. Due to the complexity of the system, many diagrams are needed to minimize the risk of ambiguities and lack of understanding. Using Model-Based Systems Engineering (MBSE) software for modeling the DNBR algorithm were used. These diagrams then serve as the baseline of the reverse engineering process and speeding up the development process. In addition, the use of MBSE ensures that any additional information obtained from auxiliary sources can then be input into the system model, ensuring data consistency.

• Journal of the Korean Institute of Gas
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• v.26 no.3
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• pp.1-9
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• 2022

The causes of accidents occurring in chemical plants vary, but 96% of industrial accidents occurring worldwide are caused by workers' unsafe behavior. The International Labour Organization (ILO) has announced 20 elements of workers' anxiety-warning behaviors that occur on multiple occasions at industrial sites in order to warn them of the risk of accidents caused by workers' anxiety-driven behavior, and to prevent industrial accidents, workers' anxiety-driven behavior should be controlled under stress In this study, major types of unsafe behavior were analyzed on the basis of information on the accident investigation history of domestic workspaces in order to find out how workers can manage their unsafe behavior. Based on the results of the analysis of the major anxiety war behavior, the root cause of causing anxiety war behavior was analyzed using the Swiss Cheese Model, and each root cause management method was proposed.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.45 no.2
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• pp.37-47
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• 2022

The Act on the Punishment of Serious Accidents to Prevent Large-scale Disasters, including Ferry Sewol and Taean Thermal Power Plant, passed the National Assembly on January 8, 2021, and has been in effect since January 27, 2022. However, the law, in which the representative of the headquarters is unlimitedly responsible for each worker's accident, is somewhat unreasonable at a time when a company owns dozens to hundreds of construction sites due to the nature of the construction industry. I agree with the purpose of enacting the law to reduce chronic serious accidents at construction sites, but it is necessary to carefully reconsider the implementation of the law in that punishment alone cannot achieve industrial safety. Previous studies focused on revising the Occupational Safety and Health Act, but there are few studies on the impact on the construction industry after the implementation of the Serious Accident Act. Therefore, this study attempts to derive problems related to the application of the Serious Accident Act and present improvement measures. To this end, after analyzing previous studies, SWOT analysis was performed by applying the Delphi method to derive strengths, weaknesses, opportunities, and threats. In addition, the results of two surveys of safety experts such as public institutions, academia, and companies were reflected, and its countermeasures were presented as follows. S/O strategy: establishing on-site execution capabilities of health and safety management system; W/O strategy: expanding legal and system execution checks; S/T strategy: establishing a risk response system; W/T strategy: expanding consulting by external specialized institutions

• Nuclear Engineering and Technology
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• v.54 no.1
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• pp.84-96
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• 2022

In the worst case, a temporary ignition source (also known as transient combustibles) between two electrical panels can damage both panels. Mitigation strategies for electrical panel fires were previously developed using fire modeling and risk analysis. However, since they do not comply with deterministic fire protection requirements, it is necessary to analyze the boundary values at which combustibles may damage targets depending on various factors. In the present study, a sensitivity analysis of input variables related to the damage threshold of two electrical panels was performed for dimensionless geometry using a Fire Dynamics Simulator (FDS). A new methodology using a damage evaluation map was developed to assess the damage of the electrical panel. The input variables were the distance between the electrical panels, the vertical height of the fuel, the size of the fire, the wind speed and the wind direction. The heat flux was determined to increase as the vertical distance between the fuel and the panel decreased, and the largest heat flux was predicted when the vertical separation distance divided by one half flame length was 0.3-0.5. As the distance between the panels increases, the heat flux decreases according to the power law, and damage can be avoided when the distance between the fuel and the panel is twice the length of the panel. When the wind direction is east and south, to avoid damage to the electrical panel the distance must be increased by 1.5 times compared to no wind. The present scale model can be applied to any configuration where combustibles are located between two electrical panels, and can provide useful guidance for the design of redundant electrical panels.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.11
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• pp.1644-1652
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• 2022

In the case of safety training where practical training is impossible due to risk problems, training contents using realistic media such as virtual reality or augmented reality are becoming a new alternative. In this paper, we propose a smoke modeling method that can be applied to safety-training contents implemented with realistic media technology. When an accident occurs in a hazardous area such as a petrochemical plant, visibility is not secured due to gas leakage and fire. In order to create such a situation, it is important to realistically express smoke. The proposed method is a smoke model implementation technique that can be effectively applied to the background of complex passages and devices such as petrochemical plants. In the proposed method, the smoke is expressed using volumetric rendering in the post-processing stage for the resulting image of scene rendering. Implementation results in the background of the factory show that the proposed method produces models that can express the smoke realistically.

• Journal of People, Plants, and Environment
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• v.24 no.5
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• pp.469-483
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• 2021

Background and objective: If the Nelumbo nucifera spreads in a wetland at a high density, it can have considerable positive and negative ecological effects on habitats. For this reason, it is necessary to precisely investigate the impacts of its rapid proliferation. This study was conducted to propose the distribution and management of N. nucifera, which can cause the degradation of wildlife habitats due to the rapid spread of internal and external environmental factors that may affect the Junam wetland ecosystem. Methods: For the investigation and analysis of physical and ecological characteristics, factors of the abiotic environment such as general weather conditions, topography and water depth structure, and soil and water quality analysis, and bioenvironment characteristics such as changes in the N. nucifera community distribution were evaluated. To assess whether the differences in the soil depth and physicochemical characteristics between the N. nucifera community and the aquatic plant community are statistically significant, a One-way ANOVA was executed. Results: N. nucifera was presumably introduced in approximately 2007 and observed at a prevalence of only 0.8% in 2009, but had expanded to 11.1% in 2014. After that, the area was increased to 19.3% in 2015 and 40.0% in 2017, about twice that of the previous survey year. The rapid diffusion of an N. nucifera colony can have adverse effects on wildlife habitats and biodiversity at Junam Wetland. To solve these problems, four management methods can be proposed; water level management, mowing management, installation of posts and removal of lotus roots. Control of the N. nucifera community using these methods was judged to be suitable for cutting and water level management when considering expansion rate, water level variation, and wildlife habitat impacts. Conclusion: As the biotic and abiotic environmental factors are different for each wetland, it is necessary to determine the timing and method of management through a detailed investigation.

• Journal of Ecology and Environment
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• v.46 no.4
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• pp.324-333
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• 2022

Background: The Korean scarlet dwarf, Nannophya koreana Bae (Odonata: Libellulidae), is anendangered dragonfly with an increasing risk of extinction owing to rapid climate changes and human activities. To prevent extinction, the N. koreana population and their habitat should be protected. Therefore, suitable habitat evaluation is important to build the N. koreana restoration project. The habitat suitability index model (HSI) has been widely used for habitat evaluation in diverse organisms. Results: To build a suitable HSI model for N. koreana, 16 factors were examined by seven experienced researchers. A field survey for N. koreana observed sites and spatial analysis were conducted to improve the model. Five factors were finally selected by this procedure (crown density, open water surface, water depth, pioneer plant cover, and type of water source). Finally, the N. koreana HSI model was generated with the five adjusted factors based on interview, field survey, and spatial analysis. This model was validated by a current N. koreana habitat in 2021. With this model, 46 sites in Uljin-gun, Korea, were surveyed for N. koreana habitats; five sites were identified as core habitats and seven as potential core habitats. Conclusions: This model will serve as a strong foundation for the N. koreana restoration project and as a reference for future studies on N. koreana and other endangered insect populations. Further analysis and long-term data will improve the efficacy of this model and restore endangered wildlife.

• Korean Journal of Agricultural Science
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• v.49 no.4
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• pp.749-760
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• 2022

Omics-driven synthetic biology is a multidisciplinary research field that creates new artificial life by employing genetic components, biological devices, and engineering technique based on genetic knowledge and technological expertise. It is also utilized to make valuable biomaterials with limited production via current organisms faster, more efficient, and in huge quantities. As the bioeconomic age begins, and the global synthetic biology market becomes more competitive, investment in research and development (R&D) and associated sectors has grown considerably. By overcoming the constraints of present biotechnologies through the merging of big data and artificial intelligence technologies, huge ripple effects are envisaged in the pharmaceutical, chemical, and energy industries. In agriculture, synthetic biology is being used to solve current agricultural problems and develop sustainable agricultural systems by increasing crop productivity, implementing low-carbon agriculture, and developing plant-based, high-value-added bio-materials such as vaccines for diagnosing and preventing livestock diseases. As international regulatory debates on synthetic biology are now underway, discussions should also take place in our country for the growth of bioindustries and the dissemination of research findings. Furthermore, the system must be improved to facilitate practical application and to enhance the risk evaluation technology and management system.

• Journal of Plant Biotechnology
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• v.35 no.4
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• pp.245-256
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• 2008

The current legislation in South Korea clearly states that the tolerance threshold on the adventitious presence of GMO in environment-friendly agricultural products is 3.0% and no GM seed should be detected in their planting seed batches. To date, in Korea, there is no approved GM crop for commercial cultivation in field. However, several GM crops including rice, Chinese cabbage, potato and wild turf grass are currently under risk assessment for their environmental release. Also Korean government (Rural Development Administration, RDA) announced that 11 institutes including universities have been currently certified to carry out a risk assessment of GM crops. Meanwhile, the cultivated area and certified quantities of environment-friendly crops (organic, pesticide-free and low-pesticide) are sharply increasing every year according to the report of National Agricultural Products Quality Management Service (NAQS). In detail, in 2007, the certified quantities of environment-friendly agricultural products were elevated up to 100-fold for organic, 171-fold for pesticide-free and 2,324-fold for low-pesticide crops when compared with those in 1999. The total certified quantity of environment-friendly cereal crops in 2007 was equivalent to 6.4% of total production of cereal crops. Moreover, 24% of total production of root and tuber crops such as potato and sweet potato were certified for environment-friendly agricultural products. In these circumstances, I strongly suggest that current legislations on GM crop's safety management should be revised to include strategies for the coexistence of GM with non-GM crops, especially environment-friendly crops before GM crop is approved to be cultivated for commercialization. Since all types of crops are grown in an open environment, the adventitious presence of GM crops among non-GM crops is inevitable if appropriate measures for coexistence are not established for species by species such as isolation distance, workable management measures to minimize admixture.

• The Korean Journal of Ecology
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• v.28 no.5
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• pp.305-320
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• 2005

Recently 64 species in Korea have been ranked as rare and endangered taxa by the Ministry of Environment using two categories, I and II. The original threat categories produced by the Ministry of Environment were developed to provide a standard for specifying animals and plants in danger of extinction and has been influential sources of information used in species conservation in Korea. However, the criteria by Ministry of Environment were applied to the whole taxa only by regional boundaries, especially in South Korea, rather than international context, and it also lacked an explicit framework that was necessary to ensure repeatability among taxa because of the absence of quantitative criteria to measure the likelihood of extinction. The World Conservation Union (IUCN) has developed quantitative criteria for assessing the conservation status of species. The threatened species categories, the 2000 IUCN Red List, proposed by SSC (Species Survival Commission) of IUCN have become widely recognized internationally. Details of threatened Korean plants, identified by applying the IUCN threat categories and definitions, were listed and analyzed. The number of species identified as threatened was only 34 out of 64 taxa (48.4%), while the rest of taxa were rejected from the original lists. Many of the species (51.6%, 33 taxa) excluded from the original list proposed by Ministry of Environment do not qualify as Critically Endangered, Endangered or Vulnerable because these taxa were widely distributed either in Japan or in China/far eastern Russia and there is no evidence of substantial decline in these countries. An evaluation of taxa in Korea has been carried out only based on subjective views and qualitative data, rather than quantitative scientific data, such as rates of decline, distribution range size, population size, and risk of extinction. Therefore, the national lists undermine the credibility of threatened species lists and invite misuse, which have been raised by other cases, qualitative estimate of risk, political influence, uneven taxonomic or geographical coverage. The increasing emphasis on international responsibilities means that global scale is becoming more significant. The current listings by Environment of Ministry of Korea should be challenged, and the government should seek to facilitate the resolution of disagreements. Especially the list should be flexible enough to handle uncertainty and also incorporates detailed, quantitative data. It is suggested that the highest priorities for the Red List should be given to endemic species in Korea first. After setting up the list of endemic species to Korea, quantitative data on population size and structure, distributional range, rated of decline, and habitat fragmentation should be collected as one of long term projects for the Red list categories. Transparency and accountability are the most important key factors. Also, species assessors are named and data sources referenced are required for the future objective evaluations on Korean plant taxa.