• Proceedings of the Safety Management and Science Conference
• /
• 2008.04a
• /
• pp.443-450
• /
• 2008

This paper is to present design principle and operation strategy of acceptance control chart by the use of OC-Based sampling inspection for continuous data. The unified control limits for acceptance control chart when considering both APL(Acceptable Process Level) and RPL(Rejectable Process Level) are proposed. The control limits can be also extended to the acceptance control chart with unknown process standard deviation.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.29 no.2
• /
• pp.145-152
• /
• 2009

Currently almost all in-service-inspection techniques, applied in domestic nuclear power plants, are partial to field inspection technique. These kinds of techniques are related to managing nuclear power plants by the operation of foreign-produced inspection devices. There have been so many needsfor development of native in-service-inspection device because there is no native diagnosis device for nuclear power plant inspection yet in Korea. In this research, we developed several core techniques to make an automated ultrasonic pipe inspection system for nuclear power plants. A high performance multi-channel ultrasonic pulser/receiver module, an A/D converter module and a digital main CPU module were developed and the performance of the developed modules was verified. The S/N ratio, noise level and signal acquisition performance of the developed modules showed proper level as we designed in the beginning.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.37 no.1
• /
• pp.19-28
• /
• 2017

In this paper, detailed safety inspection reports on the 915 expressway bridges which had been published from 1996 to 2010 are collected and condition of these bridges are analyzed. Damages are categorized into 'damage by defect', 'damage by physical force', and 'damage by deterioration' and the concept of damage possession rate is introduced to investigate the occurrence time and the characteristics of damages. Based on the top 10 damage patterns of expressway bridges and the deterioration characteristics of heavy snow and freezing cold area, reasonable improvement direction of inspection activity is suggested. From this study, it is known that improvement of inspection regularization during construction or at completion stage of bridges is needed. Since the deterioration progress of the heavy snow and freezing cold area is faster than that of general area, environmental characteristics should be considered in inspection activity. The results of present study can be widely used for improvement of inspection activity of expressway bridges.

• Journal of Food Hygiene and Safety
• /
• v.34 no.4
• /
• pp.340-347
• /
• 2019

We performed a safety survey on residual pesticides in dried agricultural products. A total of 110 samples of dried agricultural products distributed in Gyeonggi-do were analyzed for 263 pesticides according to multi class pesiticide multiresidue method. Ten types of pesticides were detected in 10 samples. Chlorpyrifos was detected in Ricinus communis leaves, chlorpyrifos, hexaconazole, pyridalyl in Chwinamul (wild aster), diniconazole, isoprothiolane, lufenuron in radish leaves, hexaconazole in Cirsium setidens (Korean thistle), bifenthrin, and chlorothalonil, boscalid, and pyraclostrobin in pepper leaves. The detection rate of pesticides was 9.1%, and among these samples, one was detected over Maximum Residue Limits (MRLs). In the validation study, the values of limit of detection (LOD), limit of quantitation (LOQ), coefficient of determination ($R^2$) and recovery were in the range of 0.002~0.027 mg/kg, 0.006~0.083 mg/kg, 0.9964~1.0000 and 74.8~118.9%, respectively. The Positive List System (PLS) was newly introduced as part of the safety management of residual pesticide in agricultural products in Korea in 2019. With the application of the PLS, if the MRL is not established, 0.01 mg/kg limit is applied uniformly. In spite, these of strengthened residue limits, the MRLs of dried agricultural products are still insufficient. Therefore, this study could be utilized as basic data for the setting of proper MRLs.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2006.11a
• /
• pp.281-284
• /
• 2006

After building a ship in a shipyard, there are so many repeated inspection of welding seam defects and painting status before delivering to the ship's owner. An inspection on the bottom part of a ship in commercial service should be done in every two years for the purpose of safety and for the prevention of ship speed deterioration. conventional welding seam inspection systems are rely on the visual inspection by human or the ultrasonic inspection for the selective part of a ship. This paper suggests a remote controlled inspection system for the examination of large ships or steel structures. The proposed system moves in contact with the ship under inspection and have a CCD camera to provide visual-guidance information to a remotely located human worker. Additionally this system utilizes a weld line tracking algorithm for an optimal position control. We verified the effectiveness of the inspection system by experimental data.

• Journal of the Korean Society of Safety
• /
• v.25 no.4
• /
• pp.36-41
• /
• 2010

This paper seeks to survey and analyze the status of obligatory execution from key institutional aspects that have taken effect according to laws on creating safe environment for laboratory and of general details such as the level of satisfaction on the part of people engaged in research activity regarding the laws after they have taken effect. The subjects of this study were MA and PhD graduate students in science and engineering who are primarily involved in research. This questionnaire survey was focused on finding basic data required for safety education for researcher and for efficient safety management by examining the correlation between education time and level of satisfaction. The collected data were analyzed by using frequency analysis, descriptive statistics, one way anova by SPSS12 package. The results obtained by this study are as follow. 1) Awarences of safety management rules, ordinary inspection, safety education were around 70% and other law clauses were around 50%. 2) The general satisfaction after the Laboratory Safety Act enforcement was usual level with 4.72 points in 7. 3) Researchers demanded ordinary inspection and protective equipment in a safe environmental composition. 4) The safety education time for improvement of a safe consciousness level was needed 12h or 24h at 1 years.

• Journal of the Korean Society of Safety
• /
• v.33 no.3
• /
• pp.27-32
• /
• 2018

Nowadays, to prevent electrical accidents in Korea, inspectors directly performed checking general electrical facilities as a cycle from every one to three years. It is difficult to presuppose an omen because intact conditions of electrical equipments are not kept at the time of inspection. In this paper, in order to ensure effectiveness of an online basis electric inspection, we developed an electrical safety IoT system using LoRa communication technology to enable monitoring mainly electrical safety components such as overcurrent, overvoltage, resistive leakage current, and power. Then we proposed a method for verifying performances of the prosed electrical safety IoT system. Resistive leakage currents are calculated by using difference of phase between voltages and currents. We verified that average errors are 0.97%, which reference goal is ${\pm}5%$ for a device, through reliability test according to conditions. Results of this research can be used as basic study materials to develop technologies for measuring three phase leakage current and for implementing public electrical safety. platform.

• Journal of the Korean Society of Safety
• /
• v.34 no.1
• /
• pp.45-52
• /
• 2019

Accident analysis models were developed to improve the construction site safety and case studies was conducted. In 2016, 86% of fatality accidents occurred due to simple unsafe acts. Structure related accidents are less frequent than the non structure related causes, but the number of casualties per accident is two times higher than non structure one. In the view of risk perception, efforts should be given to reduce accidents caused by low frequency - high consequence structure related causes. In case of structure related accident, structural safety inspection and management (including quality), ground condition management / inspection technology, and provision of risk information delivery system in case of non structure related accident were proposed as a solution. In analysis of relationship between safety related stakeholder, the main problem were the lack of knowledge of controller and player, loss of control due to duplicated controls, lack of communication system of risk information, and relative position error of controller and player.

• Journal of the Korea Institute of Building Construction
• /
• v.23 no.3
• /
• pp.327-336
• /
• 2023

The focus of this research was to devise a conceptual methodology for drone usage and to assess the viability of safety checklist items specific to drone application in safety oversight. The appraisal was grounded in a focus group interview involving professionals from construction management and safety fields. The proposed process was segmented into four stages: 1) pre-flight phase for flight plan development, 2) drone flight phase for safety condition inspection utilizing checklist items, 3) post-flight phase for visual asset analysis, and 4) documentation and management phase. Furthermore, the research scrutinized the applicability of 32 distinct safety checklist items for drone operations. The primary aim of this investigation was to probe the possible deployment of drones as part of construction safety inspections at work sites. However, it bears mentioning that subsequent research should strive to gather a more extensive sample size through questionnaire surveys, thereby facilitating quantitative analysis. Administering such surveys would yield more comprehensive data compared to a focus group interview, which was constrained by a limited participant count. In summation, this study lays a foundational groundwork for understanding the potential advantages and challenges associated with integrating drones into construction safety management.

• International Journal of Internet, Broadcasting and Communication
• /
• v.15 no.4
• /
• pp.311-325
• /
• 2023

In the construction machinery rental market, there are frequent cases of sublease through large-scale rental companies or rental through mediation organizations without legal grounds. In addition, institutional improvement of the construction machine safety management system has been required due to concerns over the internalization of legal inspections due to the lack of type approval data and construction machine history management during the construction machine inspection process. The government is responsible for securing safety of construction machinery and promoting mechanization of construction machinery by efficiently managing the construction machinery market by setting safety management such as type approval, registration, and inspection of construction machinery. In order to efficiently implement this, it is required to establish a platform for renting construction machinery and collecting safety management information. We presented a plan to build a public platform for construction machinery to secure the soundness of the construction machinery rental market and to improve safety management.