• Journal of the Korean Society of Visualization
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• v.21 no.1
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• pp.67-73
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• 2023

In the study, pool boing critical heat flux (CHF) was experimentally investigated depending on the length of heaters. A smooth silicon oxide surfaces are used as the boiling surfaces. As the results of pool boiling experiments based on distilled water in ambient pressure condition, the CHF decreased as the length of the heater increased. By the high speed imaging, it was shown that the number of vapor columns increased as the length of the heater increased. Comparing the number of vapor columns and the CHF according to the heater length, the change in the CHF according to the heater length was analyzed based on the hydrodynamic instability.

• Fourth Industrial Review
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• v.1 no.2
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• pp.9-16
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• 2021

Purpose - O2O (online to off-line) is a new economic concept being emerged in the 4^th industrial age. Automobile distribution is also undergoing a change to the O2O system. In overseas, vehicles are already being sold through various online platforms. The purpose of this study is to analyze the domestic and foreign automobile distribution structure and intends to suggest the desirable direction of automobile sales in the 4th industrial age. Research design, data, and methodology - Through the investigation of previous studies and the actual cases, the advantages and disadvantages and trends of different types of automobile distribution structures. Result - It can be seen that domestic and foreign automobile brands have quite diverse distribution structures such as direct managed system, agency system, dealer system, direct sales system, online system and online/offline parallel system. Each type has its own characteristics. Conclusion - The distribution structure of automobiles is very diverse, and in particular, it is rapidly changing to an online sales system thanks to the development of information and communication technology and Internet technology and the popularization of smartphones. Through the online system, consumers can quickly and conveniently obtain vehicle information. Although the online sales system has many advantages, it requires continuous management

• Journal of The Korean Society of Agricultural Engineers
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• v.65 no.3
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• pp.1-13
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• 2023

Local governments play a critical role in achieving carbon neutrality and reducing national carbon emissions. To manage carbon emissions effectively, it is essential for local governments to analyze regional carbon emissions. In this study, we developed a model for estimating carbon emissions based on land use and analyzed regional characteristics of carbon emissions to suggest policies for achieving carbon neutrality at the regional level. Our model for calculating carbon emissions is based on an analysis of the activities that contribute to carbon emissions for each land use, and we established the spatial scope of carbon emission calculation. We applied this model to the cities and counties in Gyeongsangnam province, calculating carbon emissions from settlement and agricultural production activities and comparing regional characteristics of carbon emissions. Our analysis showed that areas with larger populations generally produced higher emissions in all categories, but we observed different results in terms of unit emissions, emissions divided by area, population, and household. Based on these findings, we propose policies such as increasing the generation of new and renewable energy using public institutions, promoting the conversion to cleaner cooking and heating energy sources, and encouraging the adoption of eco-friendly automobiles on roads. We believe that our analysis of the spatial and regional characteristics of carbon emissions can help local governments establish effective policies for reducing carbon emissions in their regions.

• International journal of advanced smart convergence
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• v.11 no.1
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• pp.94-100
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• 2022

It is common for commercial vehicles to make the top part according to the use after making the bear chassis, and to connect various devices with the bear chassis. Various brackets used in bear chassis for the development of all automobiles, including commercial vehicles, play a role of connecting the components required for driving and operating the car to the car body. In commercial vehicles, components necessary for operation are installed in the bear chassis; that is, the bear chassis of commercial vehicles is a space where the devices required for driving and operating the vehicle are installed. The devices required for the configuration of the vehicle are drive, brake, exhaust and steering, etc. These devices are basically connected to the body, the front axis, or the rear axis. The part interlinking the apparatuses required for the vehicle drive to the car body or axis is bracket. In this study, we analyzed the boundary conditions to evaluate the stability of the three brackets that connect the components of the car to the front axis of the new type of 30-seater bus in the development process. In order to analyze the boundary conditions, the boundary conditions according to the driving condition of the vehicle were classified. For stress analysis to evaluate the stability of brackets according to the driving state of the vehicle, it is reasonable to give the bracket a boundary condition of harsh conditions.

• Fourth Industrial Review
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• v.2 no.1
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• pp.1-8
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• 2022

Purpose - O2O (online to off-line) is a new economic concept being emerged in the 4^th industrial age. Automobile distribution is also undergoing a change to the O2O system. In overseas, vehicles are already being sold through various online platforms. The purpose of this study is to analyze the domestic and foreign automobile distribution structure and intends to suggest the desirable direction of automobile sales in the 4th industrial age. Research design, data and methodology - Through the investigation of previous studies and the actual cases, the advantages and disadvantages and trends of different types of automobile distribution structures. Result - It can be seen that domestic and foreign automobile brands have quite diverse distribution structures such as direct managed system, agency system, dealer system, direct sales system, online system and online/offline parallel system. Each type has its own characteristics. Conclusion - The distribution structure of automobiles is very diverse, and in particular, it is rapidly changing to an online sales system thanks to the development of information and communication technology and Internet technology and the popularization of smartphones. Through the online system, consumers can quickly and conveniently obtain vehicle information. Although the online sales system has many advantages, it requires continuous management.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.74-75
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• 2021

In the recent 2017 annual average fine dust concentration (PM2.5) statistics released by the Organization for Economic Cooperation and Development (OECD), Korea has a high concentration of 25.14㎍/m3, which is about twice the average of 12.5㎍/m3 in OECD countries. Fine dust (PM2.5) is the main source of secondary pollutant production by the reaction of primary pollutants emitted from automobiles and thermal power plants, mainly composed of sulfates, nitrates, and organic carbon. The permeable block is an eco-friendly product that prevents rainwater from collecting on the surface of the road because it does not penetrate the groundwater properly, and is widely constructed on sidewalks or parking lots to recharge groundwater in case of rain. In addition, the pavement of the permeable block is a fundamental solution to reduce pollution by preventing rainwater from flowing into the stream, and it also has the advantage of easy replacement as well as low replacement costs. Therefore, this study was a basic experiment to produce permeable blocks mixed with TiO2 and diatomite to improve indoor air quality, and intended to analyze the flexural strength and compressive strength of permeable blocks mixed with TiO2.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.05a
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• pp.524-526
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• 2021

As the invention of automobiles and construction of roads for vehicles began, the occurrence of traffic accidents began to increase. Accordingly, efforts were made to prevent traffic accidents by changing the road construction method and using signal systems such as traffic lights, but until now, numerous human and property damages have occurred every year due to traffic accidents caused by freezing of the road due to bad weather. In this paper, we propose a method of transmitting ice detection data detected using vehicle sensor data to vehicle navigation to reduce traffic accidents caused by road freezing.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.05a
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• pp.521-523
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• 2021

As the invention of automobiles and construction of roads for vehicles began, the occurrence of traffic accidents began to increase. Accordingly, efforts were made to prevent traffic accidents by changing the road construction method and using signal systems such as traffic lights, but even today, numerous human and property damages have occurred due to traffic accidents caused by freezing of the road due to bad weather. In this paper, in order to reduce traffic accidents due to road freezing, we propose a method of transferring the ice detection information obtained by deep learning of infrared wavelength data obtained using an infrared camera to the vehicle's navigation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.68-69
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• 2020

Recently, the problem of air pollution is drawing attention as a social problem worldwide. Particularly, fine dust is the biggest issue among air pollutants, and it is analyzed that fine dust is generated from air pollutants such as burning fossil fuels such as petroleum or coal, or exhaust gases from automobiles. In addition, yellow dust originating from China adjacent to Korea flows into the Korean Peninsula in a western wind, causing the concentration of fine dust to deteriorate. Fine dust is a harmful substance to the human body such as asthma or respiratory disease, and awareness of the risk is also increasing to a degree designated as a primary carcinogen. In this study, as a method for improving the indoor air quality, the Properties of the matrix according to the mixing ratio of powdered activated carbon based on blast furnace slag are reviewed. The flexural strength and compressive strength were measured, and a fine dust concentration measurement experiment will be conducted later.

• Journal of Powder Materials
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• v.30 no.3
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• pp.255-261
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• 2023

Aluminum alloys are widely utilized in diverse industries, such as automobiles, aerospace, and architecture, owing to their high specific strength and resistance to oxidation. However, to meet the increasing demands of the industry, it is necessary to design new aluminum alloys with excellent properties. Thus, a new method is required to efficiently test additively manufactured aluminum alloys with various compositions within a short period during the alloy design process. In this study, a combinatory approach using a direct energy deposition system for metal 3D printing process with a dual feeder was employed. Two types of aluminum alloy powders, namely Al6061 and Al-12Cu, were utilized for the combinatory test conducted through 3D printing. Twelve types of Al-Si-Cu-Mg alloys were manufactured during this combinatory test, and the relationship between their microstructures and properties was investigated.