• Journal of the Korea institute for structural maintenance and inspection
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• v.3 no.2
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• pp.233-240
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• 1999

Even though the recent construction safety disasters not only result in the loss inside construction sites but also become to a large public disasters, safety activities are managed in an irrational way and safety rules are ignored in the construction sites which leads to occur same type of disasters repeatedly. In this paper, a fuzzy set theoretic approach to risk analysis is proposed as an alternative to the techniques currently used in the general construction projects safety. Then the concept of risk evaluation using linguistic representation of the likelihood, exposure and consequences is introduced. A risk assessment model using approximate reasoning technique base on fuzzy logic is presented to drive fuzzy values of risk and numerical example for risk analysis is also presented to illustrate the results.

• Journal of Korean Society for Quality Management
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• v.23 no.4
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• pp.74-89
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• 1995

In recent years, the safety of customers and the demand for rights to be protected from the risk have become stronger than ever day by day, and the function concerning product liability(PL) and quality assurance(QA) has been emphasized. Basically these functions can be obtained by inspection and there is the single rectifying sampling inspection for attribute (KSA-3105) as an existing method. But we can not say this method is good enough because of limitations in the range of applications and the approximate design of inspection methods which can not meet the rapidity and accuracy of quality information transfer according to the maturity of information period. Therefore, in this paper, a new algorithm is developed which can design the accurate inspection method by using the linear cost function that has not been considered in the existing inspection methods. Also in addition to this, a optimal rectifying sampling inspection plan, contributing to minimize the total costs, can be developed by programming the algorithm developed in this study and it can be applied to any field having many processes almost limitlessly.

• Journal of the Korean Society of Safety
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• v.36 no.1
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• pp.18-25
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• 2021

In many developed countries, such as South Korea, efficiently maintaining the aging infrastructures is an important issue. Currently, inspectors visually inspect the infrastructure for maintenance needs, but this method is inefficient due to its high costs, long logistic times, and hazards to the inspectors. Thus, in this paper, a novel crack inspection approach for concrete bridges is proposed using integrated image processing techniques. The proposed approach consists of four steps: (1) training a deep learning model to automatically detect cracks on concrete bridges, (2) acquiring in-situ images using a drone, (3) generating orthomosaic images based on 3D modeling, and (4) detecting cracks on the orthmosaic image using the trained deep learning model. Cascade Mask R-CNN, a state-of-the-art instance segmentation deep learning model, was trained with 3235 crack images that included 2415 hard negative images. We selected the Tancheon overpass, located in Seoul, South Korea, as a testbed for the proposed approach, and we captured images of pier 34-37 and slab 34-36 using a commercial drone. Agisoft Metashape was utilized as a 3D model generation program to generate an orthomosaic of the captured images. We applied the proposed approach to four orthomosaic images that displayed the front, back, left, and right sides of pier 37. Using pixel-level precision referencing visual inspection of the captured images, we evaluated the trained Cascade Mask R-CNN's crack detection performance. At the coping of the front side of pier 37, the model obtained its best precision: 94.34%. It achieved an average precision of 72.93% for the orthomosaics of the four sides of the pier. The test results show that this proposed approach for crack detection can be a suitable alternative to the conventional visual inspection method.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.4
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• pp.96-104
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• 2017

A one-shot system (device) refers to a system that is stored for a long period of time and is then disposed of after a single mission because it is accompanied by a chemical reaction or physical destruction when it operates, such as shells, munitions in a defense weapon system and automobile airbags. Because these systems are primarily related with safety and life, it is required to maintain a high level of storage reliability. Storage reliability is the probability that the system will operate at a particular point in time after storage. Since the stored one-shot system can be confirmed only through inspection, periodic inspection and maintenance should be performed to maintain a high level of storage reliability. Since the one-shot system is characterized by a large loss in the event of a failure, it is necessary to determine an appropriate inspection period to maintain the storage reliability above the reliability goal. In this study, we propose an optimal inspection policy that minimizes the total cost while exceeding the reliability goal that the storage reliability is set in advance for the one-shot system in which periodic inspections are performed. We assume that the failure time is the Weibull distribution. And the cost model is presented considering the existing storage reliability model by Martinez and Kim et al. The cost components to be included in the cost model are the cost of inspection $c_1$, the cost of loss per unit time between failure and detection $c_2$, the cost of minimum repair of the detected breakdown of units $c_3$, and the overhaul cost $c_4$ of $R_s{\leq}R_g$. And in this paper, we will determine the optimal inspection policy to find the inspection period and number of tests that minimize the expected cost per unit time from the finite lifetime to the overhaul. Compare them through numerical examples.

• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.3
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• pp.191-201
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• 2001

In spite of the increasing construction of segmental PSC box girder bridges, the techniques associated with real-time monitoring, construction control and safety assessment during construction have been less developed compared with the construction techniques. Thus, the development of an integrated system including real-time measurement and monitoring, control and safety assessment system during construction is necessary fur more safe and precise construction of the bridges. This study presents a prototype integrated monitoring system for preventing abnormal behavior and accidents under construction stages, that consist of behavior control system for precise construction, reliability-based safety assessment system, and structural analysis. Also, a prototype software system is developed on the basis of the proposed model. It is successfully applied to the Sea-Hae Grand Bridge built by FCM. The integrated system model and software system can be utilized for the safe and precise construction of segmental PSC bridges during construction.

• Computers and Concrete
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• v.33 no.5
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• pp.595-603
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• 2024

In the construction industry, there has been a surge in the implementation of high-tech equipment in recent years. Various technologies are being considered as potential solutions for future construction projects. Building information modeling (BIM), which utilizes advanced equipment, is a promising solution among these technologies. The need for safety inspection has also increased with the aging structures. Nevertheless, traditional safety inspection technology falls short of meeting this demand as it heavily relies on the subjective opinions of workers. This inadequacy highlights the need for advancements in existing maintenance technology. Research on building safety inspection using 3D laser scanners has notably increased. Laser scanners that use light detection and ranging (LiDAR) can quickly and accurately acquire producing information, which can be realized through reverse engineering by modeling point cloud data. This study introduces an innovative evaluation system for building safety using a 3D laser scanner. The system was used to assess the safety of an existing three-story building by implementing a reverse engineering technique. The 3D digital data are obtained from the scanner to detect defects and deflections in and outside the building and to create an as-built BIM. Subsequently, the as-built structural model of the building was generated using the reverse engineering approach and used for structural analysis. The acquired information, including deformations and dimensions, is compared with the expected values to evaluate the effectiveness of the proposed technique.

• Korea Trade Review
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• v.47 no.5
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• pp.95-113
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• 2022

Tariffs on pharmaceuticals are generally low, but the time-consuming and costly licensing procedures of importing countries may act as barriers to trade. Accordingly, in terms of improving export competitiveness through cost reduction of exporting countries and improving public health for importing countries, international regulatory collaboration is effective for both countries. However, little is known about the impact of cross-border cooperation in pharmaceutical regulation on international trade. This study empirically analyzed the effect of cross-border regulatory collaboration on pharmaceutical trade using the gravity model. It was confirmed that the regulatory collaboration measures had a trade promotion effect in all drugs(HS29+HS30), finished drugs (HS30), and vaccines (HS300220). This study is meaningful in that it empirically analyzed with the consideration of the reference pharmacopoeia, safety and effectiveness in addition to the GMP inspection used in the previous study.

• Journal of the Korea institute for structural maintenance and inspection
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• v.3 no.3
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• pp.187-194
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• 1999

In this study, a series of items on the safety and stability of cracked main structure in subway are investigated and analyzed. Cracks due to dry contraction under the construction can be found when a tensile stress of cross section is higher than tensile strength at a value of coefficient of dry contraction $200{\times}10^{-6}$. It is concluded that there is no problems when load carrying capacity, that is, an ability of resisting loads of structure is enough in this analytical model. Also, it is concluded that this model has a desirable serviceability because a width of bending crack is lower than allowable one.

• Journal of the Society of Disaster Information
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• v.18 no.1
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• pp.228-240
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• 2022

A comprehensive safety management system will be required in accordance with the implementation of the Major Disaster Punishment Act for close-up safety management of construction sites. Safety management level evaluation management requires a comprehensive relationship between safety management under the Construction Technology Promotion Act and health and health management system under the Industrial Safety and Health Act. Purpose: Safety under the Serious Accidents Punishment Act. The ultimate goal is to study the comprehensive analysis and relationship of health management and to improve the safety evaluation level of health and health management. Methods: The feasibility of the questionnaire was confirmed through the second Delphi analysis of construction site experts and safety managers, and the regression coefficient and path analysis of potential variants in safety management, safety management, health management and safety inspection were confirmed. Result and Conclusion: In the structural model, the regression coefficient (89%) from safety management, health system, and safety management to safety inspection execution and lambda values of appropriate observation variables were confirmed. In the path analysis, the total effect (.809) was confirmed by mediating health hygiene in the relationship between health plan establishment adequacy and post-inspection management, and the path coefficient (.82) of temporary structure safety was confirmed.

• Journal of the Korean Society of Safety
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• v.20 no.1 s.69
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• pp.153-157
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• 2005

The injury accidents in fishing vessels account for $67.2\%$ of all marine injury casualties$(1997\~2001)$ and is on an increasing trend every year. Also, it is remarkable for the injury accidents to be basically caused by human errors. This study aims to investigate the human error of injury accidents in fishing vessels and presents the injury preventing program in them. Human errors were analysed by the methods such as SHELL & Reason Hybrid Model, GEMS Model adopted by International Maritime Organization(IMO). Based on the analysis, the following propositions were made to reduce the fishing vessels accidents by human errors : improvement of hazard awareness and quality of personnel, establishment of safety management system, and enforcement of vessels inspection.