• 한국안전학회지
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• 제27권5호
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• pp.95-98
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• 2012

There are many high-rise apartment building construction in Korea. There was an accident to pass through worker head by rebar dropped from height place. Therefore, low cost-high effectiveness method to prevent this type of accident should be revised and applied into the construction site. This study is to find out which method could be effectively applied to a site with low cost. Practical field test at 4th floor, 10th floor of apartment building site using re-bar diameter D10, D13, D16, D19, D22 with a length of 1 m, 1.5 m, 2 m, 2.5 m, 3 m which are common by used in a site. The test has also been done with a cover of styrofoam thickness 4.5 cm and thickness 9cm on field drop preventing net. One sheet of styrofoam thickness 45 mm has approximately two times stronger than only prevention net, It is found. Also, Two sheets have approximately two times stronger than one sheet of it.

• 대한치과기공학회지
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• 제31권2호
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• pp.31-38
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• 2009

In recent year, the population for sports has been increased and lots of wounded patients at the oral & facial portion were troubled with the accidents. So, it was needed to protect them from the sports accident, by the use of the mouthguard appliance. This study was done as ae guide for selection of the mouthguard materials. Such mouthguards classified as E.V.A., PE, silicone as material, Scheu(Germany), Tru-Tain(U.S.A.), Dreve(Germany) as companies, 1.5mm, 3.0mm, and 4.0mm as thickness and single sheet, soft double sheet, hard double sheet methods were selected for experiment to compare the fracture protect test. The obtained results are as follows. 1. All types of mouthguards, whatever differences there are in material, production company, procedure and the thickness, were effective for fracture protect effect. 2. The most effective one for fracture protection was recommended as E.V.A. in material, and Tru-Tain in company. 3. More thick, and soft & hard multi sheets productions were more effective for fracture protection.

• 대한기계학회논문집A
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• 제30권5호
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• pp.481-487
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• 2006

Spot-welding is a widely used manufacturing method for thin-sheet components, especially in mass-production industries such as the car industry. Automobiles are often constructed by multi-lap spot welding to secure the passenger from the accident, where optimisation of the welding conditions is a major economic consideration. This research is conducted to investigate weldability characteristics with various welding conditions on the 4-lap spot welded joint of structural steel sheets in automobile. The relationship between the tensile-shear strength and the indentation depth has been investigated to propose the optimum welding conditions. The welding current and the welding time have a greater effect on the welding characteristics than the electrode force. It was found that the electrode force has a relatively close relationship with the expulsion occurrence. The design curves for optimum welding are proposed for the 4-lap spot welded joint.

• 한국산업융합학회 논문집
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• 제7권1호
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• pp.69-82
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• 2004

Recently, in the food, paper, steel and plastic industries, plate or sheet type products have been produced by the rolling drum. Steam heating drums are introduced into plastic products facilities in order to keep the density, microstructure, and strength of material uniformly. The drum journal can not help being concentrated by stresses due to the bending and torsion. Especially the drum, heated by high pressure steam, might be exposed in the steam leakage accident. First of all, the stresses on the steam drum journal are to be analyzed, and a case study proper to the subject was performed with a scraped journal, in order to investigate the failure characteristics as well as the initiation and propagation of fatigue cracks, and most probable circumstances of crack initiation. As the result of this study, it is suggested that newly installed drum journal be thoroughly inspected at the next periodic maintenance intervals for evidence of cracking, the microstructure examination and hardness measurements to prevent steam drum from the failure accident.

• Composites Research
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• 제34권2호
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• pp.115-122
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• 2021

복합재료 중에서 SMC(sheet molding compound) 복합재료는 자동차의 차체 성형에 주로 쓰이고 있다. 자동차 산업에서는 차량 사고를 고려하여야 하므로 재료의 충돌 거동 및 특성에 관한 연구는 필수적이다. 충돌은 짧은 시간에 일어나기 때문에 육안으로 확인이 어렵다. 따라서 충돌 거동을 확인하기 위해서는 유한요소 모델을 이용한 충돌 손상 해석이 필요하다. 충돌 손상 해석을 위해서는 SMC 복합재료의 손상 모델에 대한 파라메터가 요구된다. 본 연구에서는 SMC 복합재료의 손상 모델에 대한 파라메터를 획득하기 위해 인공신경망 기법을 적용하였다. LS-DYNA에서 파라메터에 따른 결과를 이용하여 대체 모델을 구성하였다. 자유 낙하 충돌 실험에서 얻은 흡수 에너지와 인공신경망 모델을 이용한 흡수 에너지를 비교하여 최적화된 파라메터를 획득하였다. 획득한 파라메터를 유한요소 모델에 적용해 결과를 비교하여 파라메터의 신뢰성을 검증하였다.

• 한국산업보건학회지
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• 제19권4호
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• pp.370-380
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• 2009

Reliable hazard and risk communication is needed to prevent the safety accident & occupational disease through right use of chemicals and MSDS(Material Safety Data Sheet) is mainly used as such a tool of communication. MSDS policy has been put into effect in order to prevent the safety accident & occupational disease through right use of chemicals and fulfill workers' right to know. If information on MSDS lacks reliability due to its inaccuracy, prevention of the various effects related with environmental safety & health in advance is not possible to achieve. The most essential thing regarding authoring MSDS is to exactly evaluate the composition and ingredients of the chemical and include reliability-guaranteed information. Therefore, in this study reliability was evaluated on MSDSs in 15 aromatic hydrocarbons(benzene, toluene, xylene, etc.) manufacturers and ways to secure reliability of MSDS were suggested. The results showed 93.5% of composition agreement rate and 89% of reliability on each section in MSDSs. In order to curb MSDSs with low reliability, examination on CBI(confidential business information) in MSDS, certification of MSDS, collection and verification of MSDS are suggested.

• 한국항해항만학회지
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• 제42권6호
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• pp.459-468
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• 2018

원양어선 제501 오룡호는 황천 중인 베링해에서 조업 후 피항하던 중 개구부를 통한 침수로 인하여 침몰하였으며 많은 선원들이 사망하고 실종되었다. 본 연구에서는 사고선박 침몰사고의 진행상황 별 유동수 영향과 어획물 배치 등을 고려한 선박복원성 계산을 KST-SHIP (선박안전기술공단 선박계산시스템)을 사용하여 수행하고 사고선박의 침몰사고 시의 침수 후 선박복원성을 분석하였다. 먼저 만재출항상태 (Full Load Departure Condition)에서의 사고선박의 비손상 복원성 계산서와 KST-SHIP을 사용한 비손상 선박복원성 계산 결과를 비교하여 검증하고, 사고선박의 출항 시부터 사고 직전까지의 배수량에 따른 비손상 복원성 계산을 수행하여 비손상 복원성을 분석하였다. 또한 사고선박 침몰사고 시의 진행상황 별 침수 후 선박복원성 계산을 수행하여 침수 후 복원성도 분석하였다.

• 한국안전학회지
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• 제36권4호
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• pp.71-79
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• 2021

In this study, a real-scale fuel-cell room of volume 1.36 m³ is constructed to confirm the explosion characteristics of hydrogen-air mixture gas in a hydrogen-powered house. A volume concentration of 40% is applied in the fuel-cell room as the worst-case scenario to examine the most severe accident possible, and two types of doors (made of plastic sheet and wood) are fabricated to observe their effects on the overpressure and impulse. The peak overpressure and impulse based on distance from the ignition source are experimentally observed and assessed. The maximum and minimum overpressures with a plastic-sheet door are about 20 and 6.7 kPa and those with a wooden door are about 46 and 13 kPa at distances of 1 and 5 m from the ignition source, respectively. The ranges of impulses for distances of 1-5 m from the ignition source are about 82-28 Pa·s with a plastic-sheet door and 101-28 Pa·s with a wooden door. The amount of damage to people, buildings, and property due to the peak overpressure and impulse is presented to determine the safe distance; accordingly, the safe distance to prevent harm to humans is about 5 m based on the 'injuries' class, but the structural damage was not serious.

• 한국산업보건학회지
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• 제33권3호
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• pp.365-374
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• 2023

Objectives: After the MSDS submission and non-disclosure review system was introduced in January 2021, there were compliance difficulties in the field. Accordingly, for the establishment of the MSDS system, the government intends to investigate what has been improved and what urgently needs to be improved in the future, and to suggest detailed improvement plans. Methods: The background and problems of urgent difficulties in the field handling chemicals were investigated, and realistic improvement plans were derived through review of other laws related to the MSDS system and overseas cases. Results: In order to guarantee the safety of the public while at the same time promoting corporate R&D, it is necessary to alleviate the non-disclosure screening system for chemical substances for R&D, and to improve the irrationality of failing to implement the non-disclosure screening system due to information on unclassified substances being circulated. For this reason, it seems necessary to ease the requirement to submit all ingredients. In addition, it is necessary to strengthen punishment to raise awareness so that health problems do not occur due to the harmfulness and danger of hidden substances among workers who handle chemical substances and downstream users due to false descriptions in MSDS. Conclusions: All members of our society, including chemical manufacturers/importers and handling companies, academia, civil society, and the government, each subject of chemicals, should take an interest in the entire process from production to disposal of chemicals and work together to prevent harm to the public.

• 한국가스학회지
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• 제6권4호
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• pp.1-7
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• 2002

인적 오류(human error)는 공장설비의 설계, 제작, 건설, 운전, 유지$\cdot$보수의 모든 단계에서 발생할 수 있으며 사고의 대부분이 인적 오류의 영향과 관계되어 있는 것으로 조사되고 있다. 본 연구에서는 현장의 작업자 행동 특성 및 오류 메커니즘을 확인하고, 평가분류 쉬트를 활용하여 공정에서 발생하는 인적 오류를 분석하였다. 또한 ASEP HRA 절차를 이용하여 인적 오류 확률(HEP) 산정 알고리즘을 구축하여 현장에서 쉽게 인적 오류를 분석할 수 있는 ASEP HEP 프로그램을 개발하였다. 이를 이용하여 화학공장에서의 가능한 인적 오류사고를 예방하고 보다 체계적인 인적 오류 방지대책을 수립할 수 있다고 판단된다.