• 한국기계가공학회지
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• 제21권3호
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• pp.110-117
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• 2022

A chiller cooler absorbs the thermal energy of water to generate cold water and supplies the generated cold water to a cold water pipe buried in the wall of a small mobile modular house to greatly increase the cooling area. An attempt was made to reduce the required cooling time significantly. A small chiller cooler suitable for the cooling load of a small mobile modular house with an area less than 3.3 m² was employed. When cooling is done during summer using a chiller cooler installed outdoors, heat absorption energy loss occurs in the cold water pipe owing to the high temperature. To address this, a study was conducted to reduce the endothermic energy loss significantly. As the mass flow rate of the cold water flowing inside the cold water pipe increased, the temperature decrease gradient of the cold water increased. From the start of the cooling operation, the air temperature of the small mobile modular house decreased linearly in proportion to the operation time. Furthermore, the temperature of the air inside the small mobile modular house decreased in proportion to the increase in the flow of water inside the cold water pipe.

• Journal of Biosystems Engineering
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• 제33권3호
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• pp.186-195
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• 2008

In this paper, a prototype tele-operative system with a mobile base was developed in order to automate cultivation of house melon. A man-machine interactive hybrid decision-making system via tele-operative task interface was proposed to overcome limitations of computer image recognition. Identifying house melon including position data from the field image was critical to automate cultivation. And it was not simple especially when melon is covered partly by leaves and stems. The developed system was composed of 5 major modules: (a) main remote monitoring and task control module, (b) wireless remote image acquisition and data transmission module, (c) three-wheel mobile base mounted with a 4 dof articulated type robot manipulator (d) exchangeable modular type end tools, and (e) melon storage module. The system was operated through the graphic user interface using touch screen monitor and wireless data communication among operator, computer, and machine. Once task was selected from the task control and monitoring module, the analog signal of the color image of the field was captured and transmitted to the host computer using R.F. module by wireless. A sequence of algorithms to identify location and size of a melon was performed based on the local image processing. Laboratory experiment showed the developed prototype system showed the practical feasibility of automating various cultivating tasks of house melon.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.579-586
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• 2022

Modular building is a fast-growing construction method, mainly due to its ability to drastically reduce the amount of time it takes to construct a building and produce higher-quality buildings at a more consistent rate. However, while modular construction is relatively safer than traditional construction methods, workers are still exposed to hazards that lead to injuries and fatalities, and these hazards could be controlled using emerging smart technologies. Currently, limited information is available at the intersection of modular construction, safety risk, and smart safety technologies. This paper aims to investigate what aspects of modular construction are most dangerous for its workers, highlight specific risks in its processes, and propose ways to utilize smart technologies to mitigate these safety risks. Findings from the archival analysis of accident reports in Occupational Safety and Health Administration (OSHA) Fatality and Catastrophe Investigation Summaries indicate that 114 significant injuries were reported between 2002 and 2021, of which 67 were fatalities. About 72% of fatalities occurred during the installation phase, while 57% were caused by crushing and 85% of crash-related incidents were caused by jack failure/slippage. IoT-enabled wearable sensing devices, computer vision, smart safety harness, and Augment and Virtual Reality were identified as potential solutions for mitigating identified safety risks. The present study contributes to knowledge by identifying important safety trends, critical safety risk factors and proposing practical emerging methods for controlling these risks.