• 한국산업보건학회지
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• 제33권2호
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• pp.215-229
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• 2023

Objectives: To validate the effectiveness of a real-time chemical exposure monitoring system developed by KOSHA (Korea Occupational Safety and Health Agency), we applied the system to a workplace in the electronics industry for 153 days. Methods: The monitoring system consisted of a PID chemical sensor, a LTE communication equipment, and a web-based platform. To monitor chemical exposure, four sets of sensors were placed in two manufacturing tasks - inspection and jig cleaning - which used TCE as a degreasing agent. We reviewed previous reports of work environment measurements and conducted a new work environment measurement on one day during the period. The PID sensor systems detected the chemical exposure levels in the workplace every second and transmitted it to the platform. Daily average and maximum chemical exposure levels were also recorded. Results: We compared the results from the real-time monitoring system and the work environment measurement by traditional methods. Generally, the data from the real-time monitoring system showed a higher level because the sensors were closer to the chemical source. We found that 28% of jig cleaning task data exceeded the STEL. Peak exposure levels of sensor data were useful for understanding the characteristics of the task's chemical use. Limitations and implications were reviewed for the adoption of the system for preventing poisoning caused by chemical substances. Conclusions: We found that the real-time chemical exposure monitoring system was an efficient tool for preventing occupational diseases caused by chemical exposure, such as acute poisoning. Further research is needed to improve the reliability and applicability of the system. We also believe that forming a social consensus around the system is essential.

• 한국ITS학회 논문지
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• 제17권6호
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• pp.153-172
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• 2018

화물차량의 과적은 도로 포장의 파손 및 교량 등 도로구조물의 파괴, 대형 교통사고 발생 등의 주요한 원인 중 하나로서 오랜 시간동안 도로 교통 분야에서 중요한 연구분야였다. 본 연구에서는 과적 문제 해결을 위해 급속도로 발전하는 IT 및 빅데이터 활용기술을 접목하여 화물차량의 과적운행패턴 분석 및 차체부착중량계중시스템를 활용한 과적예방 효과를 분석하였다. 이를 위해 기존 화물차량과적 관련 문헌 조사와 상용 차체부착중량계중시스템 기술 조사를 진행하였으며, 과적적발 정보 분석을 통해서 대표적인 과적차량의 유형을 선정하였다. 과적유형에 맞는 차량을 10대 선정, 차체부착중량계중시스템을 설치함으로써 화물차량의 정보를 실시간으로 모니터링하여 연구 데이터를 수집하였다. 화물차량의 축중량과 총중량 데이터는 상하차 작업횟수 대비 과적비율 등으로 분석하였으며, 차체부착중량계중시스템 유무에 따른 그 변화추이를 확인하여 차체부착중량계중시스템 적용의 과적예방효과를 확인할 수 있었다. 다만, 시험차량 표본수가 전체를 대표할 수 있을 정도로 충분하지 못하기 때문에 향후 확대 시험을 통해서 추가적인 연구가 가능할 것으로 판단된다.

• International Journal of Aeronautical and Space Sciences
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• 제17권4호
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• pp.467-475
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• 2016

Ultrasonic propagation imaging (UPI) has shown great potential for detection of impairments in complex structures and can be used in wide range of non-destructive evaluation and structural health monitoring applications. The software implementation of such algorithms showed a tendency in time-consumption with increment in scan area because the processor shares its resources with a number of programs running at the same time. This issue was addressed by using field programmable gate arrays (FPGA) that is a dedicated processing solution and used for high speed signal processing algorithms. For this purpose, we need an independent and flexible block of logic which can be used with continuously evolvable hardware based on FPGA. In this paper, we developed an FPGA-based ultrasonic propagation imaging system, where FPGA functions for both data acquisition system and real-time ultrasonic signal processing. The developed UPI system using FPGA board provides better cost-effectiveness and resolution than digitizers, and much faster signal processing time than CPU which was tested using basic ultrasonic propagation algorithms such as ultrasonic wave propagation imaging and multi-directional adjacent wave subtraction. Finally, a comparison of results for processing time between a CPU-based UPI system and the novel FPGA-based system were presented to justify the objective of this research.

• 한국측량학회지
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• 제14권1호
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• pp.17-25
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• 1996

스틸비디오 CCD카메라는 수치영상의 획득과정이 크게 단순화되어 컴퓨터에 직접 연결되지 않고도 독립적으로 수치영상을 획득하여 자체내에 영상을 저장할 수 있는 융통성을 갖추고 있다. 본 연구에서는 각종 산업분야에서 요구되는 품질검사, 구조물의 모니터 링 등에 스틸비디오 카메라를 이용한 수치근접사진측량 시스템의 수행성을 평가하고자 하였다. 수치 영상측정 에서 필수적 인 sub-pixel 측정기 법을 제시하고, 고해상도의 DCS420 스틸비디오 카메라에 대한 기하학적 자체검정 및 구조물에 대한 시험측정을 실시하였다. 자체검정 광속조정의 결과 1:46,000을 초과하는 대상공간 정확도를 얻을 수 있었으며 산업적 음용에 수치영상을 이용한 본 근접사진측량 시스템의 정확도 잠재성과 작업의 효율성을 입증할 수 있었다.

• 제어로봇시스템학회논문지
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• 제6권2호
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• pp.207-216
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• 2000

This paper introduces an effective system design method to develop a customer oriented product using a design optimization process and to select a set of critical design paramenters,. The process results in the development of a successful product satisfying customer needs and reducing development risk. The proposed scheme adopted a five step QFD(Quality Function Deployment) in order to extract design parameters from customer needs and evaluated their priority using risk factors for extracted design parameters. In this process we determine critical design parameters and allocate them to subsystem designers. Subsequently design engineers develop and test the product based on these parameters. These design parameters capture the characteristics of customer needs in terms of performance cost and schedule in the process of QFD, The subsequent risk management task ensures the minimum risk approach in the presence of design parameter uncertainty. An application of this approach was demonstrated in the development of weld quality monitoring system. Dominant design parameters affect linearity characteristics of weld defect feature vectors. Therefore it simplifies the algorithm for adopting pattern classification of feature vectors and improves the accuracy of recognition rate of weld defect and the real time response of the defect detection in the performance. Additionally the development cost decreases by using DSP board for low speed because of reducing CPU's load adopting algorithm in classifying weld defects. It also reduces the cost by using the single sensor to measure weld defects. Furthermore the synergy effect derived from the critical design parameters improves the detection rate of weld defects by 15% when compared with the implementation using the non-critical design parameters. It also result in 30% saving in development cost./ The overall results are close to 95% customer level showing the effectiveness of the proposed development approach.