• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.5
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• pp.721-731
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• 2018

Manpower in domestic construction sites is becoming more and more aging. Various methods have been devised to prevent productivity and quality deterioration of construction due to absence of skilled workers and difficulty in supplying manpower. Especially, many researchers study various methods such as Machine Guidance (MG) and Remote Machine Control to improve productivity and quality. Although many prior studies have been conducted since the advent of MG, There is lack of field test in a difficult site to stakeout. In this study, field test of MG excavator was carried out at difficult site to stakeout, and productivity analysis and quality evaluation were conducted. As a result of the analysis of productivity, the minimum value was 20.5%, the maximum value was 56.9%, and the average productivity in 4 days was 38.3% higher than the standard product. As a result of the analysis of quality, the horizontal error ${\pm}1cm$ and the vertical error ${\pm}2cm$ confirmed in the previous study were verified.

• Korean Journal of Construction Engineering and Management
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• v.25 no.2
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• pp.3-10
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• 2024

The purpose of this study is to analyze the effects of smart construction equipment applied at the construction site of the first smart city in the Korea and derive an application strategy for the utilization of smart construction equipment. To achieve this, aythors examined the practical effects and issues of safety systems and construction systems utilizing machine guidance (MG) technology, which is a representative smart construction equipment used in civil engineering construction sites. Both the MG safety system and MG construction system were found to be sufficiently effective in improving construction productivity. However, there are challenges that need to be addressed, such as the approval process for work results using MG systems, system changes due to frequent replacement of on-site equipment, and usability improvements for elderly on-site workers. The study presented some solutions that have been implemented on-site to address these issues. The utilization effects and issues presented in the study were analyzed through direct feedback from workers and managers who have utilized the MG technology on-site for a considerable period of time. These results can be used as preliminary data for the similar construction projects, considering the limited availability of empirical analysis data for equipment automation.

• Journal of Drive and Control
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• v.17 no.1
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• pp.37-43
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• 2020

An intelligent excavator can be divided into Machine Guidance (MG), semi-automatic, and unmanned by technology. The MG technology excavator is equipped with a tilt sensor on each link of the excavator and a GPS is installed on the excavator body to inform the user of the position of the excavator bucket end. Machine control (MC) technology that assists the user's work can be divided into semi-automatic and fully automatic technology. The semi-automatic MC equipment has already been commercialized by Komatsu and Caterpillar. The MC excavator is equipped with an electro-hydraulic system, sensors and controllers to control the excavator bucket end according to the user's needs. In this study, the semi-automated excavator modified based on manual excavator, is equipped with an electro-hydraulic system, a controller system, multi-sensors and a control algorithm is developed to assist in excavation work such as leveling and grading. By applying the developed technology, it was possible to confirm productivity improvement compared to manual digging and leveling work. In the future, further research to improve the accuracy of the hydraulic precision control and collaborative work with heterogeneous construction equipment such as dump truck and automated collaboration tasks technology could be developed.

• Journal of Dental Rehabilitation and Applied Science
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• v.25 no.4
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• pp.361-374
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• 2009

For successful osteogenesis around the implants, interaction between implant surface and surrounding tissue is important. Biomechanical bonding and biochemical bonding are considered to influence the response of adherent cells. But the focus has shifted surface chemistry. The purpose of this study is to evaluate the MC3T3-E1 osteoblast like cell responses of magnesium (Mg) ion implanted titanium surface produced using a plasma source ion implantation method. Commercially pure titanium disc was used as substrates. The discs were prepared to produce four different surface, A: Machine turned surface, B: Mg implanted surface, C: sandblasted surface, D: sandblasted and Mg implanted surface. MC3T3 El osteoblastic like cells were cultured on the disc specimens. Cell adhesion, proliferation, differentiation, and synthesis of extracellular matrix were evaluated. The cell adhesion morphology was evaluated by SEM. RT PCR assay was used for assessment of cell adhesion, proliferation and differentiation. ALP activity was measured for cell differentiation. The results of this study were as follows: 1. SEM showed that cell on Mg ion groups was more proliferative than that of non Mg ion groups. On the machine turned surface, cell showed some degree of contact guidance in aligning with the machining grooves. 2. In RT PCR analysis, osteonectin and c-fos mRNA were more expressed on sandblasted and Mg ion implanted group. 3. ALP activity was not significantly different among all groups. Within the limitations of this study, the following conclusions were drawn: It might indicate Mg ion implanted titanium surface induce better bone response than non Mg ion groups.