• Journal of Practical Engineering Education
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• v.13 no.3
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• pp.559-566
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• 2021

The aggregate gradation analysis is a study that evaluates the accuracy of a specific purpose for the aggregate gradation analysis results essential for construction-related major education. This study is to evaluate the effect of aggregate moisture content on aggregate gradation analysis. The change in the moisture content of the aggregate stored in the asphalt plant cold bin and stock piles was monitored for one year, and based on the results, a sample of aggregate with different moisture content was produced. The gradation curve for each aggregate sample was analyzed to evaluate the effect of aggregate moisture content on aggregate gradation analysis. As a result of the gradation evaluation, it was confirmed that as the moisture content increased, the particle size error for particles less than 5 mm increased in the gradation analysis of the oven-dried aggregate, and this error increased as the particle size decreased. In addition, for aggregate particles of 5 mm or more, it was confirmed that the error in gradation analysis rapidly decreased due to the increase in the moisture content. An analysis was performed on the effect of the error in gradation analysis on the management of hot-bin aggregates in asphalt plants. As a result of the analysis, it was found that the minimum aggregate size of the first hot-bin in a general asphalt plant was 2.38 mm or more, so the maximum gradation error due to the non oven-dry aggregate was less than 2%. Therefore, it seems possible to use the results of the gradation analysis of cold bin non oven-dry aggregate for quality management of asphalt mixture production.

• Conservation Science in Museum
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• v.28
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• pp.17-34
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• 2022

This study seeks to identify the material characteristics of earthenware excavated from the Bangi-dong Ancient Tomb No. 3 and the articulated stone-mound tomb of the Seokchon-dong ancient tombs in the Songpa region, and analyze the homogeneity and the firing temperature of the materials used at each excavated site. The remains have been studied relatively recently, and the groups of tombs in which they were found demonstrate the transition of ancient Korean burial systems, and at the same time, provide important archaeological data about those in power at the time. The earthenware pottery excavated from the two sites examined in the study were buried at different times, and it is assumed that they were made by procuring weathered soil of similar gneiss, judging from the behavior of the compatible and incompatible elements and the weathering tendency found by examining the main components. In addition, the examination of the mineral composition and microstructure of clay indicates that the earthenware from Seokchon-dong was fired at 950 degrees Celsius or lower at a relatively early stage. On the other hand, the earthenware from Bangi-dong Tomb No. 3 was confirmed to have experienced temperatures below 850 degrees Celsius and above 1,000 degrees Celsius. However, it is difficult to interpret the difference as the result of the changes in firing temperature throughout the eras. It is expected that it will be possible to interpret the changes in earthenware manufacturing techniques by comparing more diverse earthenware potteries and ancient soils.

• Journal of the Korea Society of Computer and Information
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• v.27 no.9
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• pp.177-190
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• 2022

In this study, using data from the second wave of Panel Survey of Employment for The Disabled[PESD] (2016) to the sixth year (2021), the longitudinal changes between disability acceptance and job satisfaction of adult wage workers aged 20 or older with disabilities and the correlation An autoregressive cross-lagged model was applied to analyze the causal relationship. As a result of the analysis, first, the disability acceptance and job satisfaction at the previous time point of the disabled workers were stably significant to the disability acceptance(𝛽=.556~.610) and job satisfaction(𝛽=.554~.585) at the later time point. Second, disability acceptance at the previous point in time for wage workers with disabilities crosses the job satisfaction at the later time point(𝛽=.077~.090), and the job satisfaction at the previous point crosses the disability acceptance at the later time point(𝛽=.087~.092). Third, as a result of model fit analysis according to the gender group of wage workers with disabilities, the difference in the autoregressive effect between disability acceptance and job satisfaction and the cross-lagged effect between disability acceptance and job satisfaction according to the passage of time was not significant.

• Journal of Convergence for Information Technology
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• v.11 no.5
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• pp.111-117
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• 2021

With the rapid development of advanced science and technology including the 4th industrial revolution, the future battlefield environment is evolving at a rapid pace. In order to actively respond to issues such as reduction of military resources and shortening of service period, and to emphasize the realization of human-centered values, the Ministry of National Defense is re-establishing the role of the Army in accordance with the defense reform and is promoting the Warrior Platform, a next-generation individual combat system. In this paper, we intend to present the optimal warrior platform architecture suitable for the Korean Army by realizing the concept of future ground operations and analyzing overseas cases. We analyze the essential abilities required of individual combatants and the abilities required for each unit type, and specifically presents a plan for integration and linkage of warrior platform equipment. We also propose an efficient business promotion direction by presenting the data flow and power connection diagram between the devices that need integration and interworking.

• Journal of Convergence for Information Technology
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• v.11 no.8
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• pp.84-91
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• 2021

In the 21st century, a number of storm and flood disasters caused by rapidly changing climate change is increasing, and the number of flood accidents at construction sites is also increasing. However, no specific reduction measures have been presented and thereby safety management to prevent flood accident need to be improved. Therefore, in this study, the inundation pattern by downpour at the excavation site was interpreted and the inundation risk quantification method was used to classify the risk magnitude. Finally, using the fish-bone diagram, we derived the major reasons of inundation accident at construction site systematically. The simulation results showed that the inundation depths of small-scale excavation sites and excavation sites exceeded 3 m due to the fluid flowing through the excavation surface. In addition, depending on the excavation site, a high velocity temporarily observed and decreased due to the storage effect, or high velocity surpassing 10 m/s continued. Since this type of flooding can pose a risk to most or all workers, if proper management measures are insufficient, fatal damage to life and property could occur. Consideration of the roots of these disasters is judged to be helpful in understanding the causes of inundation accidents that result in casualties and presenting accident reduction measures.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.433-442
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• 2021

This study analyzed the housing market before and after the New Stay movement which was introduced in 2015. In this study, the territories having a New Stay Project and non-involved territories were analyzed based on the apartment price changes according to supply for 12 months before and after the movement date. This study used the difference-in-differences statistical technique. A comparison was carried out in Michuhol-gu, Incheon between Dowha-dong where a New Stay Project was executed, and Sungeui-dong where no project was executed, based on the movement date. It was seen that the price level in the former territory was higher than the latter demonstrating that the introduction of the New Stay Project in Dowha-dong lowered the apartment prices nearby (Sungeui-dong). A comparison in Gwonseon-gu, Suwon between Omogcheon-dong where a New Stay Project was executed and Gosaek-dong where there was no such project, based on the movement date showed that the introduction of the New Stay Project in Omogcheon-dong seemed to lower or stabilize the apartment prices nearby (Gosaek-dong). These results imply that the apartment prices in nearby areas can be stabilized if the supply volume of company-type rental houses is increased.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.108-117
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• 2021

The educational approach using Capstone Design is gradually expanding with the change in social and educational paradigms. Course development utilizing the Capstone Design in models in the department of fashion can create a positive effect in that it enhances the practical capabilities of the fashion model and expands the perspective of various fields related to fashion shows. This study proved the educational efficacy by applying the Capstone Design to the model work presentation course and investigating the implications of the design from the instructor's perspective. The research methods used to guide this course utilizing the Capstone Design were theatrical research and model development research. This study showed that learners' satisfaction for this course combined with Capstone Design was very high, and students were very satisfied with the progress of the class. The instructor's point of view in progressing this course showed the need for education from an in-depth and convergence perspective related to fashion, improvement of temporal and spatial utilization of space, concerns about establishing connections with experts and various industries, and expanding the scope of education through continuous exchanges and cooperation with industry.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.504-512
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• 2021

Sperm formation disorders and sperm quality degradation comprises the largest proportion of male infertility caused by TCDD. To solve this problem, this study examined the effects of Gobonyangjeonbang oriental medicine prescription on the endocrine function and reproductive toxicity-related indicators in rat-induced TCDD-induced reproductive. Male SD rats were divided into five groups of seven animals and tested. The normal control group was administered the vehicle and saline, the TCDD alone group was administered intraperitoneally with TCDD (2 ㎍/kg, weeks) and physiological saline, and the test group was administered orally by dividing GYB (75, 150, and 300 mg/kg) into three concentrations for six weeks. Weight loss was observed in all groups administered TCDD. Regarding the hormonal changes, a significant decrease in free testosterone was observed in the GYB 300 mg/kg group (p<0.01). In addition, some of the germ cell destruction, seminiferous tubular atrophy, and decrease in sperm count was improved in a concentration-dependent manner in the testicular tissue of the GYB-treated group. In addition, Johnsen's score and serotoli cell index (SCI) were improved in a concentration-dependent manner (p<0.05). Overall, GYB can be used in drug therapy rather than medical procedures to solve male infertility in the future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.325-333
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• 2021

With the rapidly changing era of the fourth industrial revolution, the utilization of IT technology is increasing. In addition, the demand for security authentication is increasing as shared services or IoT technologies are being developed as new business models. Security authentication is becoming increasingly important for all intelligent devices such as self-driving cars. However, most location-based security authentication technologies are being developed mainly with technologies that utilize server proximity or satellite location tracking, which limits the scope of their physical use. Location-based security authentication technology has recently been developed as a complementary replacement technology. In this study, we introduce location-based security authentication technology using cell broadcasting technology, which has a wider range of applications and is more convenient and business-friendly than existing location-based security authentication technologies. We also introduced application cases and business models related to this. In addition to the current status of technology development, we analyzed current changes in business models being employed. Based on our analysis results, this study draws the implication that technology diversification is necessary to improve the performance of innovative technologies. It is meaningful that it has found and studied advanced technologies other than existing location authentication methods and systems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.517-529
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• 2021

This study analyzes changes in the efficiency of the Department of Early Childhood Education in Korea to examine the effectiveness of the National Evaluation for Teacher Education Institution. We provide policy implications from exploring factors influencing efficiency and comparing characteristics of efficient and inefficient departments. With 149 Department of Early Childhood Education in Korea, DEA was conducted to estimate the relative efficiency, and the Tobit model was applied to explore factors affecting efficiency. The results confirm that the Department of Early Childhood in Korea is run efficiently, though there was no change in scale efficiency and relative efficiency after the two phases of the National Evaluation for Teacher Education Institution. The results show the number of books per student was significantly lower despite a significantly higher employment rate. Efficiency of college departments, department greater than 60 (per cohort), and department in metropolitan city (except Seoul area) is confirmed greater. These results provide policy implications on developing evaluation measure and processes to improve education quality and efficiency.