• 제목/요약/키워드: Safety Inspections

검색결과 247건 처리시간 0.022초

Reliability analysis for fatigue damage of railway welded bogies using Bayesian update based inspection

  • Zuo, Fang-Jun;Li, Yan-Feng;Huang, Hong-Zhong
    • Smart Structures and Systems
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    • 제22권2호
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    • pp.193-200
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    • 2018
  • From the viewpoint of engineering applications, the prediction of the failure of bogies plays an important role in preventing the occurrence of fatigue. Fatigue is a complex phenomenon affected by many uncertainties (such as load, environment, geometrical and material properties, and so on). The key to predict fatigue damage accurately is how to quantify these uncertainties. A Bayesian model is used to account for the uncertainty of various sources when predicting fatigue damage of structural components. In spite of improvements in the design of fatigue-sensitive structures, periodic non-destructive inspections are required for components. With the help of modern nondestructive inspection techniques, the fatigue flaws can be detected for bogie structures, and fatigue reliability can be updated by using Bayesian theorem with inspection data. A practical fatigue analysis of welded bogies is utilized to testify the effectiveness of the proposed methods.

Motorcycle Inspection Standards Development I (이륜자동차 검사기준 개발 I)

  • Lim, Jaemoon;Ha, Taewoong;Hong, Seungjun
    • Journal of Auto-vehicle Safety Association
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    • 제9권4호
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    • pp.48-54
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    • 2017
  • This paper presents the motorcycle inspection standards development on the vehicle identification, engine and transmission, tyres and wheels, steering and suspension, and brake system. 187 real-world motorcycles are visually and mechanically inspected according to the developed inspection standards. The non-compliance rate of the vehicle identification is 20.3% and main causes are insecure, damaged, and not clearly visible number plate. The non-compliance rate of the brake system is 15.5% and main cause is failing to meet the brake performance requirements. The motorcycle inspections standards are improved reflecting 187 cases of real-world motorcycle inspection results.

Motorcycle Inspection Standards Development II (이륜자동차 검사기준 개발 II)

  • Hong, Seungjun;Ha, Taewoong;Lim, Jaemoon
    • Journal of Auto-vehicle Safety Association
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    • 제9권4호
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    • pp.55-60
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    • 2017
  • This paper presents the motorcycle inspection standards of electrical system, frame & body, lights and speedometers. 187 real-world motorcycles are visually and mechanically inspected according to the developed inspection standards. The non-compliance rate of inspection standards of the lights is 23.7% and main causes are damage, tinting, painting and coloration of head-lamp, number plate lamp, front-rear position lights, stop lamp and direction indicators of motorcycles. Also, 28.4% of motorcycles are dropped from the luminous intensity inspection standard. Motorcycle electrical system cannot be visually inspected. The motorcycle inspections standards are improved reflecting 187 cases of real-world motorcycle inspection results.

Behavior of Dams during the 1995 Hyogoken-Nambu Earthquake and Earthquake Resistance of Dams

  • Yamaguchi, Yoshikazu
    • Proceedings of the Earthquake Engineering Society of Korea Conference
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    • 한국지진공학회 1999년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall
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    • pp.3-14
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    • 1999
  • The Hyogoken-Nambu Earthquake of January 17, 1995 inflicted severe damage in the Hanshin and Awaji areas such as has never been seen in Japan in recent years. The safety inspections of the dams conducted in the area by site offices and dam experts immediately after the earthquake showed that there was no damage affecting the safety of the dams although slight damage was observed in several dams. The investigation also revealed that the peak accelerations at dam sites were much smaller than those at soil sites. The Ministry of construction organized the Committee on Evaluattion of Earthquake Resistance of Dams after the earthquake. The Committee confirmed through dynamic analysis that the dams designed in accordance with the present design criteria in Japan are safe under the magnitude of shaking that occurred close the source fault of the Hyogoken-Nambu Earthquake.

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A Case Study on the Assessment of Damaged Cause for the Damaged Reinforced Concrete Pier

  • Chai, Won-Kyu;Kim, Kwang-Il;Son, Young-Hyun
    • International Journal of Safety
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    • 제10권1호
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    • pp.16-21
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    • 2011
  • In this thesis, appearance inspection, compressive strength of concrete test, arrangement of bar inspection, survey, and bearing stress analysis were performed on a damaged coping of reinforced concrete pier to investigate the damage cause. According to the performed a series of inspections, it was found that the coping of pier was damaged during PSC (Pre-stressed Concrete) beam construction. In this thesis, the repair method for damaged pier was studied. The repair procedure used in this thesis was follows : chipping for damaged part, clean by high-pressure, installation of wire mesh, coating of surface hardening, construction of section restoration material, copula grinding, and prevent coating for far-infrared radiation.

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A Literature Review of Unmanned Aircraft System (UAS) Integrated Constructed Facility Condition Inspections (무인항공체계 기반 시설물 상태점검 최근 연구동향 분석)

  • Kwon, Jin-Hyeok;Yun, Jiyeong;Youn, JongYoung;Lee, Donghoon;Kim, Sungjin
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 한국건축시공학회 2021년도 봄 학술논문 발표대회
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    • pp.172-173
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    • 2021
  • In recent, unmanned Aircraft Systems (UAS) have been widely used for various purposes, such as safety inspection, facility condition inspection, progress monitoring, in the architecture engineering, and construction (AEC) industry. This technology can provide visual assets regarding the conditions of construction jobsites as well as constructed facilities during flying over the point of interests. With the significant interests in this advancement, the recent studies have presented how the UAS can be applied fro different types of facilities (e.g., buildings, power genereation systems, roads, or bridges) to inspect the current conditions of them for safe operations as well as public's safety. This study reviewed the receent studies to document their scientific findings and practical contributions, as well as provided the overview of further implications for future studies.

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Safety diagnosis process for deteriorated buildings using a 3D scan-based reverse engineering model

  • Jae-Min Lee;Seungho Kim;Sangyong Kim
    • Smart Structures and Systems
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    • 제31권1호
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    • pp.79-88
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    • 2023
  • As the number of deteriorated buildings increases, the importance of safety diagnosis, maintenance, and the repair of buildings also increases. Traditionally, building condition assessments are performed by one person or one company and various inspections are needed. This entails a subjective judgment by the inspector, resulting in different assessment results, poor objectivity and a lack of reliability. Therefore, this study proposed a method to bring about accurate grading results of building conditions. The limitations of visual inspection and condition assessment processes previously conducted were identified by reviewing existing studies. Building defect data was collected using the reverse-engineered three-dimensional (3D) model. The accuracy of the results was verified by comparing them with the actual evaluation results. The results show a 50% time-saving to the same area with an accuracy of approximately 90%. Consequently, defect data with high objectivity and reliability were acquired by measuring the length, area, and width. In addition, the proposed method can improve the efficiency of the building diagnosis process.

Proliferation of Health and Safety Documentation in Construction?

  • Smallwood, John;Bester, Deon
    • International conference on construction engineering and project management
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    • The 8th International Conference on Construction Engineering and Project Management
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    • pp.243-248
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    • 2020
  • In addition to a range of H&S documentation, a range of actions, beliefs, interventions, practices, and states are important in terms of achieving optimum construction H&S. Conclusions include that H&S documentation facilitates and assists planning, organising, leading, controlling, and coordinating H&S. Furthermore, current H&S documentation: is inappropriate in that it can be complex, generic, lengthy, onerous, repetitive (duplicative), and vague; engenders dubious practices; generally, 'does not add the potential value'; shifts the focus from the physical process, and could be improved. Recommendations include: industry associations should review their 'audit system' to interrogate the allocation of points; H&S documents must reflect the intention of the requirement; the synergy between H&S documentation, and actions, interventions, and practices should be investigated, digested, and focused upon, and 'audits', or rather inspections, should focus more on the physical process, actions, interventions, and practices, than documentation.

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A Study on Optimal Inspection Interval for the Major Components of Construction Lift (건설용 리프트의 운행정보 및 고장데이터 분석을 통한 주요 부품별 점검주기 산출 연구)

  • Soh, Jiyune;Bae, Jaehoon;Han, Choonghee;Lee, Junbok
    • Korean Journal of Construction Engineering and Management
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    • 제16권3호
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    • pp.68-77
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    • 2015
  • One of recent concerns for super-tall buildings is how to manage hoisting plans and equipment efficiently. Disasters are frequently occurred in relation to electromotive hoists and cranes which are commonly used in construction sites. For construction lifts, particularly, it is highly important to conduct regular inspections or prepare against breakdown in terms of safety. However, unfortunately the reality is that regular inspections are only flatly conducted according to operating hours only. A lift, whose life span is subject to the complicated considerations such as operating hours, loading condition, and the like of each component, is far too invalid as a means of maintenance. As a way to resolve this problem and improve its convenience and safety for users, this study intends to calculate individual inspection interval for the main components of lifts by measuring their actual operating hours with sensing technology and analyzing their historical data. The findings of study include calculation of inspection intervals for the main components of lifts and classification of components to check by the actual operating hours of lift (40, 90, 130, 400 hours), which are drawn up into tables. This will make an opportunity to suggest efficient maintenance measures by enabling prevention of safety accidents and enhancement of safety for workers. Also, it will lead to increasing productivity of works by eliminating sources of delaying the term due to the breakdown of lifts.

Exposure Assessment and Management of Ionizing Radiation (전리방사선 노출과 관리)

  • Chung, Eun-Kyo;Kim, Kab-Bae;Song, Se-Wook
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • 제25권1호
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    • pp.27-35
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    • 2015
  • Objectives: To investigate safety and health management, conditions in factories or facilities handling radiation-generating devices and radioactive isotopes were reviewed in terms of regulations of radiation safety control in Korea. Radiation exposure levels generated at those facilities were directly measured and evaluated for establishing an effective safety and health management plan. Methods: Government organizations with laws and systems of radiation safety and health were investigated and compared. There are three laws governing radiation-related employment such as occupational safety and health acts, nuclear safety acts, and medical service acts. We inspected 12 workplaces as research objects:four workplaces that manufacture and assemble semiconductor devices, three non-destructive inspection workplaces that perform inspections on radiation penetration, and five workplaces in textile and tire manufacturing. Monitoring of radiation exposure was performed through two methods. Spatial and surface monitoring using real-time radiation instruments was performed on each site handling radiation generating devices and radioactive isotopes in order to identify radiation leakage. Results: According to the occupational safety and health act, there is no legal obligation to measure ionizing radiation and set dose limits. This can cause confusion in the application of the laws, because the scopes and contents are different from each other. Surface dose rates in radiation generating devices such as implanters, thickness gages and accelerators, which were registered according to nuclear safety acts, using surveymeters, and seven of 36 facilities(19.4%) exceeded the international standards for surface radiation dose of $10{\mu}Sv/hr$. Conclusions: The results showed that occupational health and safety acts require a separate provision for measuring and assessing the radiation exposure of workers performing radiation work. Like noise, ionizing radiation will also periodically be controlled by including it in the object factors of work-environment measurement.