Visual inspection is regarded as one of the critical activities for quality control in a manufacturing company. it is thus important to improve the performance of detecting a defective part or product. There are three probable working modes for visual inspection: fully automatic (by automatic machines), fully manual (by human operators), and semi-automatic (by collaboration between human operators and automatic machines). Most of the current studies on visual inspection have been focused on the improvement of automatic detection performance by developing a better automatic machine using computer vision technologies. However, there are still a range of situations where human operators should conduct visual inspection with/without automatic machines. In this situation, human operators’performance of visual inspection is significant to the successful quality control. However, visual inspection of components assembled into a mobile camera module belongs to those situations. This study aims to investigate human performance issues in visual inspection of the components, paying more attention to human errors. For this, Abstraction Hierarchy-based work domain modeling method was applied to examine a range of direct or indirect factors related to human errors and their relationships in the visual inspection of the components. Although this study was conducted in the context of manufacturing mobile camera modules, the proposed method would be easily generalized into other industries.

The visual inspection device was developed for non-destructive test of piping from the inside. The developed components of the system can be classified as camera module, main body module named crawler module and system module. Because the system has driving part as electric motors, it can run not only the horizontal and vertical straight lines but also bend lines. The system has video processors, it can make it possible to display the video on the monitor and to save the video clips simultaneously. Several tests were performed to check the development objectives.

Due to the sewer induced ground subsidence, there is an increasing demand for the advanced visual inspection technique for the existing sewer pipe structures. This study aim to develop a new condition assessment method using visual inspection device with automatic crack extracting and real-time gas monitoring systems for large diameter glass-fiber reinforced plastic sewer pipes. In this paper, a high-precision image capturing system that automatically extracts cracks in the large-diameter sewer pipes and sewage culverts with a diameter of 1,000 mm or more, and a real-time gas detection sensor for investigator safety were considered. By analyzing the module technology of the visual inspection device, the test device and their software for system integration were developed. It is expected that the developed technique inspecting conditions of the GFRP sewer pipes using the proposed visual inspection device in this study can be effectively used for various types of underground structures in the future.

Due to the sewer induced ground subsidence, there is an increasing demand for the advanced visual inspection technique for the existing sewer pipe structures. This study aim to develop a visual inspection device and real-time transmission system of inspection data with precisely evaluated structural and operational conditions of underground sewer pipe structures. In this paper, a high-precision image capturing system that automatically extracts cracks in the large-diameter sewer pipes and sewage culverts with a diameter of 1,000 mm or more, a real-time gas detection sensor for investigator safety were studied. By analyzing the module technology of the visual inspection device, the concept design for system integration was derived, and the real time transmission system of the inspection result was developed to establish the technical basis for the commercialized device. Also the crack detection test using crack calibration was carried out for the proposed image capturing camera system, and the position accuracy using L1 grade GPS module was tested in this study. The inspection technique of the existing structure condition using the visual inspection device in this study can be effectively used for various structures types and advanced composite structures in the future.

Steel structures have been prevented from corrosion damage using by paint coating. The durability of paint coating can be changed by installed environment condition of steel structures. In this study, thus, deterioration test of paint coating was conducted for various environmental condition. Deterioration levels of paint coating specimens exposed by each artificial environment were examined from visual inspection.

In this study, Levee Visual Inspection and Water Level Detection System was developed to handle visual inspection information on the levee effectively by using mobile/intelligent CCTV system. This system will be used to manage levee reasonably, in order to prevent disaster in the riparian areas preemptively on the base of management task.

The amount of newly-built bridges has been gradually reduced so that the importance of maintenance for existing bridges which has a long services period is issued. Therefore, the maintenance budget for existing bridges is going to be consistently increased. It is needed that a reasonable decision-making methodology for existing bridge maintenance is required to effectively use the limited maintenance budget. In this study, a method of the structural vulnerability evaluation is newly suggested as the one of the evaluation stage for developing a reasonable decision-making methodology.

배수통문은 하천제방을 횡단하여 설치된 하천시설로, 연속적으로 시공되어져야 하는 제방의 특성에 반하여 불연속적인 단면을 제공함으로써 하천제방 안전성을 저하시키는 구조물로 알려져 있다. 본 논문에서는 배수통문의 효율적인 점검 체계 구축을 위하여 육안점검표 및 휴대용 단말기를 이용한 육안조사 시스템을 제시하고 향후 개선방향을 제시하였다. 제안된 육안점검표는 적용성 평가결과 간단한 육안점검에 의한 손상 파악을 통해 배수통문의 보수 계획 수립과 보수 및 정밀안전진단에 대한 투자우선순위 선정에 적용성이 높은 것으로 평가되었다.