• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.4
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• pp.483-489
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• 2020

Particulate matter is divided into PM10 (particle diameter of 10 ㎛ or less) and PM2.5 (particle diameter of 2.5 ㎛ or less), which are approximately 1/5 of the thickness of the hair. Due to its effect on the human body, lung disease, arteriosclerosis and heart It is known as a carcinogen that causes various diseases such as diseases. It is known that the main cause of such fine dust is nitrogen dioxide (NOx), which is emitted from automobiles in about 57.3% of urban roadsides. Therefore, in this study, as part of the development of functional construction materials to reduce NOx generated from road transport pollutants, comparative evaluation of NOx reduction performance was conducted according to the replacement rate of cement mortar in which cement was replaced with a porous material. In addition, the NOx reduction performance of cement mortar according to the photocatalyst application method and the number of applications was compared an d evaluated. As a result of the experiment, when activated ocher was substituted by 30%, it showed a reduction effect of about 32.7%, showing the best reduction performance.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.1
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• pp.13-24
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• 2021

Tunnel boring machine (TBM) is widely used for tunnel excavation in hard rock and soft ground. In the perspective of TBM-based tunneling, one of the main challenges is to drive the machine optimally according to varying geological conditions, which could significantly lead to saving highly expensive costs by reducing the total operation time. Generally, drilling investigations are conducted to survey the geological ground before the TBM tunneling. However, it is difficult to provide the precise ground information over the whole tunnel path to operators because it acquires insufficient samples around the path sparsely and irregularly. To overcome this issue, in this study, we proposed a geological type classification system using the TBM operating data recorded in a 5 s sampling rate. We first categorized the various geological conditions (here, we limit to granite) as three geological types (i.e., rock, soil, and mixed type). Then, we applied the preprocessing methods including outlier rejection, normalization, and extracting input features, etc. We adopted a deep neural network (DNN), which has 6 hidden layers, to classify the geological types based on TBM operating data. We evaluated the classification system using the 10-fold cross-validation. Average classification accuracy presents the 75.4% (here, the total number of data were 388,639 samples). Our experimental results still need to improve accuracy but show that geology information classification technique based on TBM operating data could be utilized in the real environment to complement the sparse ground information.

• Journal of the Korean Institute of Gas
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• v.25 no.6
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• pp.22-28
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• 2021

Combustion characteristics were examined experimentally for a swirl-stabilized double cone premixed burner nozzle used for industrial gas turbines for power generation. An original model and a variant with a different fuel injection pattern are tested to compare their combustion characteristics such as NOx, CO and stability in pressurized conditions with single burner-flame and in an ambient multi-flame conditions with multi-burners. Test results show that NOx emissions are smaller for the variant, whose number of fuel holes is reduced with the same total area of fuel holes, in ambient and pressurized single-flame conditions with single burner, which results from enhanced fuel/air mixing due to a higher penetration of fuel into the air stream. The multi-burnerflame test results show that NOx emissions are smaller for the variant due to reduced flame interactions, which, on the contrary, slightly reduces the stability margin. On-site test results fromin an actual power plants also show that NOx emissions are reduced for the variant, compared with the original one, which is in agreement with the lab test results stated above.

• Journal of Korean Elementary Science Education
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• v.40 no.4
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• pp.545-555
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• 2021

This study aims to analyze research trends by the period of elementary science education journal. A total of 1047 papers were analyzed from Volume 1 No. 1 in 1983 to Volume 39 No. 4 in 2020. The results of the study are as follows: First, the period of elementary science education journals was divided into infancy, settlement, development, and retainment period according to the number of papers. Second, the ratio of research by more than three scholars, pure or funded research was decreasing. Third, the study subjects had a high rate of research on elementary school students and elementary school teachers. Fourth, research methods were mainly research studies and experimental studies, and qualitative analysis and mixed analysis studies were increasing as data analysis methods. Fifth, the occupation of the first author was professor (45.6%), teacher (39.8%), graduate student (10.6%), and researcher (1.7%) in that order. Sixth, the regions of the corresponding author were concentrated in Seoul and Gyeongin, the metropolitan areas. Finally, in order for the "Elementary Science Education" journal to continue to play a pivotal role in leading elementary science education in the future, efforts to improve the overall journal and continuous participation and cooperation of domestic and foreign researchers, academic executives, members, and educational institutions are required.

• Analyses & Alternatives
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• v.5 no.1
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• pp.87-121
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• 2021

Since 2012, Prime Minister Shinzo Abe'sadministration began to promote women's participation and advancement in the workplace and established the Act on the Promotion of Female Participation and Career Advancement in the Workplace (the Act) in 2015. Some criticize this Act as a way to utilize women for economic development and to deal with the shrinking working population. In contrast, others point out that it is a law that can be beneficial for women. As such, this Act serves as an interesting case of a women's policy promoted by a conservative government. This paper's objective is to shed light on if and how women are substantively represented in the Diet members' statements made during the legislative debate of the bill on the Promotion of Female Participation and Career Advancement in the Workplace between 2014 and 2015. This paper asks two research questions. First, based on the mixed evaluation of the Act made in the studies about the Abe administration's women's policies, this research asks if the Diet members speak of women as resources to use for other economic and social goals or if women are substantively represented. Second, drawing insights from the literature on women's substantive representation, this research asks how Diet members speak for women. Particularly, based on the studies on conservatism and substantive representation of women, this question seeks to determine if Diet members engage in the conservative representation of women, taking women's roles as mothers and wives who provide care for children, husbands, and elders at home for granted. The results of the analysis demonstrate that the number of statements that explicitly claimed to use women was small. Second, while some Diet members of conservative political parties engaged in the conservative representation of women, there were more instances of non-conservative representation, in which a variety of types of women were represented. These findings reveal that even when the conservative government's intention to submit the bill was to utilize women rather than acting for women, Diet members could speak for various types of women and engage in the non-conservative representation of women. The findings also imply the importance of paying attention to formal and informal legislative deliberation rules to figure out how women's substantive representation can occur under a conservative government and in a legislature dominated by conservative parties.

• Journal of the Korea Convergence Society
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• v.12 no.5
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• pp.217-225
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• 2021

This study analyzed domestic research trends related to the behavior of problems with using smart devices in infants, focusing on addiction tendency. The main results of research trends are as follows: First, the total number of papers published per year is 79, and addiction proneness studies were published in various academic journals, while researchers' major was mostly concentrated in the department of education and social welfare. Second, there were 81 research topics, including actual conditions, scale development, related variables, interventions, and causal relationships. The proportion of research subjects was the highest with 60 (74.1%) research subjects, which are related variables. Third, the subjects of the study were divided into infants, caregivers, and teachers, and the main subjects of the study were mothers. Fourth, the research trends by research method were 73 quantitative studies (92.4%), 2 qualitative studies, 1 literature study, 2 mixed studies, and 1 other study. Fifth, the results of the analysis of influential factors were classified as risk factors and protection factors, which were specifically classified as individual factors, household factors, and social and environmental factors. Based on the study results, further discussion and practical suggestions were added.

• Journal of the Korean GEO-environmental Society
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• v.22 no.12
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• pp.15-24
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• 2021

In Korea, which is mostly mountainous, the proportion of tunnel and underground space development are increasing. Although the ground is reinforced by applying the ground improvement method during underground space development, accidents still occur frequently in Korea. In the grouting method, a representative ground reinforcement method, the effect was judged by comparing the total amount of injection material with the amount of injection material used during the actual grouting construction. However, it is difficult to determine whether the ground reinforcement is properly performed during construction or within the target ground. In order to solve this problem, it is necessary to study a new method for quality control during or after construction by measuring electrical resistivity after performing grouting by mixing carbon fiber, which is a conductive material, and microcement, which is a grout material. In this study, as a basic study, a cement specimen mix ed with 0%, 3%, 5%, 7% of carbon fiber was prepared to evaluate the performance of the grout material mixed with carbon fiber, which is a conductive material. The prepared specimens were wet curing for 3 days, 7 days, and 28 days under 99% humidity, and then compression wave velocity and shear wave velocity were measured. As a result of the compression wave velocity and shear wave velocity measurement, it showed a tendency to increase with the increase in the compounding ratio of carbon fibers and the number of days of age, and it was confirmed that the elastic modulus and shear modulus, which are the stiffness of the material, also increased.

• Korean Journal of Cognitive Science
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• v.33 no.4
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• pp.169-203
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• 2022

As artificial intelligence (AI) technology advances, the number of cases in which AI becomes an object or subject of moral judgment is increasing, and this trend is expected to accelerate. Although the area of AI in human society expands, relatively few studies have been conducted on how people perceive and respond to AI. Three studies examined the effect of the anthropomorphism of AI on its responsibility. We predicted that anthropomorphism would increase the responsibility perception, and perceived agency and perceived patiency for AI would mediate this effect. Although the manipulation was not effective, multiple analyses confirmed the indirect effect of perceived patiency. In contrast, the effect of perceived agency of AI was somewhat mixed, which makes the hypothesis partially supported by the overall result. This result shows that for the moral status of artificial agents, perceived patiency is relatively more critical than perceived agency. These results support the organic perspective on the moral status that argues the importance of patiency, and show that patiency is more important than agency in the anthropomorphism related study of AI and robots.

• Membrane Journal
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• v.33 no.4
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• pp.181-190
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• 2023

Wastewater purification is one of the most important techniques for controlling environmental pollution and fulfilling the demand for freshwater supply. Various technologies, such as different types of distillations and reverse osmosis processes, need higher energy input. Capacitive deionization (CDI) is an alternative method in which power consumption is deficient and works on the supercapacitor principle. Research is going on to improve the electrode materials to improve the efficiency of the process. A reverse electrodialysis (RED) is the most commonly used desalination technology and osmotic power generator. Among many studies conducted to enhance the efficiency of RED, MXene, as an ion exchange membrane (IEM) and 2D nanofluidic channels in IEM, is rising as a promising way to improve the physical and electrochemical properties of RED. It is used alone and other polymeric materials are mixed with MXene to enhance the performance of the membrane further. The maximum desalination performances of MXene with preconditioning, Ti₃C₂T_x, Nafion, and hetero-structures were respectively measured, proving the potential of MXene for a promising material in the desalination industry. In terms of osmotic power generating via RED, adopting MXene as asymmetric nanofluidic ion channels in IEM significantly improved the maximum osmotic output power density, most of them surpassing the commercialization benchmark, 5 Wm^-2. By connecting the number of unit cells, the output voltage reaches the point where it can directly power the electronic devices without any intermediate aid. The studies around MXene have significantly increased in recent years, yet there is more to be revealed about the application of MXene in the membrane and osmotic power-generating industry. This review discusses the electrodialysis process based on MXene composite membrane.

• Journal of the Korean earth science society
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• v.43 no.6
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• pp.749-761
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• 2022

As the number of National and UNESCO Global Geoparks has increased, awareness of geological heritage and local government interests have also increased. In this study, data from the geological heritage sites in the Ulsan area were summarized, a practical use plan for geological heritage was prepared based on the assessment results, and the expected effects were also presented. The value for 33 of 112 geological heritage sites identified through literature surveys was evaluated. In terms of the geological heritage types in Ulsan, there were two geological, one geomorphological, and thirty mixed-heritage sites. In the context of the geological heritage of Ulsan, rivers and coastal topography were found to be dominant, and various geomorphological and geological features, such as fossils, folds, faults, shear zones, minerals, and ore deposits are included. Based on the assessment results, there were three, eighteen, nine, and three sites in Classes I, II, III, and IV, respectively. Considering the intrinsic and subsidiary values of geological heritage, the Gangdong Coast, Jujeon Coast, Taehwagang area, Daewangam area, the Daegokri-Cheonjeonri track sites, and Mujechineup are likely to be listed as potential geosites. When the endorsement of the geopark has been promoted alongside these geosites, it can contribute to the sustainable preservation and maintenance of the geosites, satisfy the demand for science education through geo-education, and support the sustainable development of the local economy following the detailed standards for geopark certification in the Natural Parks Act. This is expected to increase the brand value of Ulsan Metropolitan City.