• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.16 no.4
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• pp.441-454
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• 2018

Since the permanent shutdown of Kori Unit 1 in 2017, a full-scale decommissioning project for a commercial nuclear reactor has been approaching. It is estimated that about 160,000 t of low-activity concrete waste will be produced from decommissioning of one unit of this commercial nuclear power reactor. Accordingly, it is necessary to review whether the effectiveness of the current regulatory framework for clearance waste (i.e. waste stream that meets activity concentration guidelines or dose criteria for clearance set forth in NSSC Notice No. 2017-65) can be maintained for the clearance of a bulk amount of concrete waste. In this regard, the IAEA SRS No. 44, which was used as a basis for revision of the Korean clearance regulations, is thoroughly analyzed and the radiological effects from four different clearance scenarios, along with input values and parameters derived from industrial practices in Korea, were evaluated. Though it is shown that the maximum annual dose from most recycling scenarios will be less than the clearance dose criterion for the normal scenario (i.e. an order of magnitude of $0.01mSv{\cdot}y^{-1}$), the radiation dose, estimated with conservative assumptions for the banking scenario, may exceed the above clearance dose criteria. Therefore, for safe and sustainable clearance of the bulk amount of concrete waste, it is required to diversify the concrete waste processors, perform more detailed site-specific assessment, and apply limiting conditions to the banking scenario.

• Journal of Energy Engineering
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• v.27 no.4
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• pp.64-69
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• 2018

The purpose of this study is to expand the use of coal ash and coal slag in thermal power plants. In addition, controlled low strength materials was developed to prevent mine settlement. Bottom ash and KR slag are mixed at ratio of 7:3 to expand the use of industrial by-products through carbonate reaction and inhibit the exudation of heavy metals. In order to efficiently fill the abandon mine, workability and physical properties were evaluated according to flow. As a result of elution of harmful substance experiment, it was confirmed that the carbonation reaction inhibited the elution of heavy metals. It was confirmed that the difference in water ratio was the difference in specific surface area of the controlled low strength materials. It was confirmed that the working efficiency is excellent when the flowability is 300mm compared to 260mm. compressive strength measurement result was relatively high at 260mm compared to 300mm because the number of pores due to decrease of water ratio was small.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.213-223
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• 2018

This study assessed the maintenance plan of the Shimbashi-Toranomon Development Area in Japan, which has recently been completed using the three-dimensional road system. In the main relevant law system, a three-dimensional road system, which enables the construction of buildings above and below the road, was applied. The specific construction regulations applying the financing power and knowledge of private business operators were applied. In the development district, city maintenance guidelines were established, and housing and shopping malls were regulated. This purpose was to promote change, unity of distance, effective use of land, and continuous urban revitalization with charm and vitality. The main features of the maintenance plan were accessibility and greenery, comfort and a sophisticated design, and a maintenance concept utilizing historical buildings and road space through the participation of local residents and the opinions of related committees. In addition, in the case of the construction of the upper and lower roads, the construction restrictions were relaxed, and the separation of the roads and the undergrounding of electric poles were promoted. The main aim was to improve the convenience of the residents and produce a pleasant road landscape.

• 한국체육학회지인문사회과학편
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• v.56 no.2
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• pp.303-320
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• 2017

This paper seeks to better understand the focal issues and persons related to Rio Olympic soccer games through social data science and analytics. This study collected its data from online news articles and comments specific to KOR during the Olympic football games. In order to investigate the public interests for each game and target persons, this study performed the co-occurrence words analysis. Then after, the study applied the NodeXL software to perform its visualization of the results. Through this application and process, the study found several major issues during the Rio Olympic men's football game including the following: the match between KOR and PIJ, KOR player Heungmin Son, commentator Young-Pyo Lee, sportscaster Woo-Jong Jo. The study also showed the general public opinion expressed positive words towards the South Korean national football team during the Rio Olympics, though there existed negative words as well. Furthermore the study revealed positive attitude towards the commentators and casters. In conclusion, the way to increase the public's interest in big sporting events can be achieved by providing the following: contents that include various professional sports analysis, a capable domain expert with thorough preparation, a commentator and/or caster with artistic sense as well as well-spoken, explanatory power and so on. Multidisciplinary research combined with sports science, social science, information technology and media can contribute to a wide range of theoretical studies and practical developments within the sports industry.

• Journal of Korea Water Resources Association
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• v.54 no.5
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• pp.301-309
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• 2021

In this study, we tried to improve the performance of the existing U-net-based deep learning rainfall prediction model, which can weaken the meaning of time series order. For this, ConvLSTM2D U-Net structure model considering temporal consistency of data was applied, and we evaluated accuracy of the ConvLSTM2D U-Net model using a RainNet model and an extrapolation-based advection model. In addition, we tried to improve the uncertainty in the model training process by performing learning not only with a single model but also with 10 ensemble models. The trained neural network rainfall prediction model was optimized to generate 10-minute advance prediction data using four consecutive data of the past 30 minutes from the present. The results of deep learning rainfall prediction models are difficult to identify schematically distinct differences, but with ConvLSTM2D U-Net, the magnitude of the prediction error is the smallest and the location of rainfall is relatively accurate. In particular, the ensemble ConvLSTM2D U-Net showed high CSI, low MAE, and a narrow error range, and predicted rainfall more accurately and stable prediction performance than other models. However, the prediction performance for a specific point was very low compared to the prediction performance for the entire area, and the deep learning rainfall prediction model also had limitations. Through this study, it was confirmed that the ConvLSTM2D U-Net neural network structure to account for the change of time could increase the prediction accuracy, but there is still a limitation of the convolution deep neural network model due to spatial smoothing in the strong rainfall region or detailed rainfall prediction.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.6
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• pp.127-139
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• 2021

This study investigates business demands for firms operating in the Busan Sasang Industrial Area for the proposed knowledge-industry innovation base. Diverse improvement arrangements are proposed for revitalization of the industrial area. For these purposes, a questionnaire survey was conducted for the examination of physical conditions and enterprise demands among firms. The major findings are as follows. Firstly, judging from the examination of physical conditions, the study area has presented a lower rate of roads and smaller individual lots of land, which would contribute to a worsening business environment for small business owners. Secondly, business request for industrial-area innovation, pilot project needs, and expected impacts demonstrated higher scores. Thirdly, an absolute majority of firms strongly supported the proposed knowledge-industry innovation base and requested an R&D center as the first anchor facility. Based on these findings, guidelines are proposed for an institutional rearrangement plan. First of all, specific field surveys dealing with networking issues and industrial dominance should be immediately carried out. In addition, the proposed knowledge-industry innovation base should be equipped with significant power of influence for the adjacent industrial areas. Lastly, major stakeholders should upgrade the cooperative mechanism for innovative change in the regional industrial complex.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.14 no.1
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• pp.22-28
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• 2021

Multivariate processes, such as chemical and mechanical process, power plants are operated in a state where several facilities are complexly connected, the fault of a particular system can also have fatal consequences for the entire process. In addition, since process data is measured in an unstable environment, outlier is likely to be include in the data. Therefore, monitoring technology is essential, which can remove outlier from measured data and detect failures in advance. In this paper, data obtained from dynamic and multivariate process models was used to detect fault in various type of processes. The dynamic process is a simulation of a process with autoregressive property, and the multivariate process is a model that describes a situation when a specific sensor fault. Mahalanobis distance was used to remove outlier contained in the data generated by dynamic process model and multivariate process model, and fault detection was performed using ICA. For comparison, we compared performance with and a conventional single ICA method. The proposed fault detection method improves performance by 0.84%p for bias data and 6.82%p for drift data in the dynamic process. In the case of the multivariate process, the performance was improves by 3.78%p, therefore, the proposed method showed better fault detection performance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.192-199
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• 2020

The blower erosion phenomenon was investigated to develop a long-life blower with a volume flow rate of 10,000 ㎥/min with the required total pressure efficiency of 83% or more. The blower performance and blower erosion were predicted through numerical analysis by computational fluid dynamics(CFD). The conditions used for numerical analysis were an air volume of 16,200 ㎥/min, a rotation speed of 893 rpm, and a temperature of 330℃. The specific gravity, particle size, and amount of the dust was 3.15, 90 ㎛~212 ㎛, and is 265 kg/min, respectively. To examine the effects of a dust deflector on erosion, erosion analysis was performed by comparing the models with and without a dust deflector. Numerical analysis showed that when the dust deflector is installed, the average tended to decrease by 167% in the impeller and 133% in the boss. CFD using the Finne's model for erosion revealed a parallel restitution coefficient of 1 and a perpendicular restitution coefficient of 0.1. The blower performance of case 5 was 691.7 mmAq, and the efficiency was 83.3% when the rotation speed and the air volume flow rate were 880 rpm and 16,200 ㎥/min, respectively.

• The Journal of the Korea Contents Association
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• v.21 no.4
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• pp.137-152
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• 2021

In North Korea, where there was little external activity, the number of overseas academic paper publications has recently increased. This study aims to quantitatively analyze North Korean papers published abroad to identify changes in North Korea's research and development trends, and to explore the possibility of developing them through joint research with domestic researchers in the future. To this end, since 1986, frequency analysis and network analysis have been conducted on papers published overseas including North Korean researchers. The analysis was conducted on authors, research institutes, countries, and research fields, and changes were analyzed before and after Kim Jong-un took office. According to the results of the analysis, as the number of foreign papers published rapidly increased during the eight years after Kim Jong-un took office, the composition of the top researchers, research institutes, and researchers with high influence in joint research also changed a lot. After Kim Jong-un came to power, the proportion of North Korean researchers and research institutes increased relatively, and a network component was formed between researchers with high influence on joint research, so it was observed that they focused on specific research topics. It was found that the major foreign collaborators or research institutes of North Korean researchers were from China.

• Maritime Security
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• v.2 no.1
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• pp.71-123
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• 2021

Seoul is under increasing pressure to choose between the US-led IndoPacific Strategy (IPS) and China's Belt and Road Initiative (BRI). Accordingly, this paper undertakes a detailed appraisal of the IPS and the BRI in the context of Korea's national policy imperatives. Based on a study of network structure by Daniel Nexon and Thomas Wright (2007), the present study seeks to identify a particular network structure within the IPS and the BRI. Through this analysis, the relationship between the core and the participant states will be addressed. Awareness of specific configurations of the IPS and the BRI is important as these reveal what participant states can expect from each network. According to Nexon and Wright, there are four types of network structure: unipolar anarchy, hegemonic order, constitutional order, and imperial order. Based on this, we argue that the IPS has a constitutional order and the BRI has an imperial order. Therefore, we suggest to Seoul that participating in the IPS may make more room for an independent foreign policy than would a BRI partnership with China. South Korea would benefit by participating in the IPS in terms of its national security, striking a favourable regional balance of power.