• Title/Summary/Keyword: Impact Safety

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Nondestructive Contactless Sensing of Concrete Structures using Air-coupled Sensors

  • Shin, Sung-Woo;Hall, Kerry S.;Popovics, John S.
    • International Journal of Safety
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    • v.7 no.2
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    • pp.17-22
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    • 2008
  • Recent developments in contactless, air-coupled sensing of seismic and ultrasonic waves in concrete structures are presented. Contactless sensing allows for rapid, efficient and consistent data collection over a large volume of material. Two inspection applications are discussed: air-coupled impact-echo scanning of concrete structures using seismically generated waves, and air-coupled imaging of internal damages in concrete using ultrasonic tomography. The first application aims to locate and characterize shallow delamination defects within concrete bridge decks. Impact-echo method is applied to scan defected concrete slabs using air coupled sensors. Next, efforts to apply air-coupled ultrasonic tomography to concrete damage imaging are discussed. Preliminary results are presented for air-coupled ultrasonic tomography applied to solid elements to locate internal defects. The results demonstrate that, with continued development, air-coupled ultrasonic tomography may provide improved evaluation of unseen material defects within structures.

Design Optimization of Safety Barrier Consisting of Steel Rail and CFRP Post (강재 레일과 CFRP 기둥으로 이루어진 방호울타리의 최적화 설계)

  • Kim, Jung Joong;Kim, Seung-Eock
    • Journal of the Korean Society for Advanced Composite Structures
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    • v.4 no.2
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    • pp.25-30
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    • 2013
  • In this study a hybrid safety barrier system consisting of steel rail and carbon fiber reinforced polymer (CFRP) post is considered. W hile CFRP post is selected for impact energy reflection due to its high strength, steel rail is selected for impact energy absorption due to its high ductility. A numerical model considering the elastoplastic behavior of steel is formulated to simulate the dynamic responses of the hybrid system subject to an impact load. A hybrid roadside guard rail system of steel rail and CFRP post is proposed and analyzed with a case study. The numerical model for the hybrid roadside guard rail system is used to find optimized design of the proposed hybrid system.

Analysis of RC beams subjected to shock loading using a modified fibre element formulation

  • Valipour, Hamid R.;Huynh, Luan;Foster, Stephen J.
    • Computers and Concrete
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    • v.6 no.5
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    • pp.377-390
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    • 2009
  • In this paper an improved one-dimensional frame element for modelling of reinforced concrete beams and columns subjected to impact is presented. The model is developed in the framework of a flexibility fibre element formulation that ignores the shear effect at material level. However, a simple shear cap is introduced at section level to take account of possible shear failure. The effect of strain rate at the fibre level is taken into account by using the dynamic increase factor (DIF) concept for steel and concrete. The capability of the formulation for estimating the element response history is demonstrated by some numerical examples and it is shown that the developed 1D element has the potential to be used for dynamic analysis of large framed structures subjected to impact of air blast and rigid objects.

Evaluation of EuroSID-2 & WorldSID in Pole Side Impact (기둥측면충돌시험에서 EuroSID-2와 WorldSID 인체모형 평가에 관한 연구)

  • Kim, Dea Up;Woo, Chang Gi
    • Journal of Auto-vehicle Safety Association
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    • v.7 no.1
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    • pp.40-44
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    • 2015
  • In recent years, WorldSID dummy has been continuously developed and investigated to be a better represent biolfidelic ATD as well as a device for replacement of the current existing EuroSID-2. In Korea, the side impact accident is one of the major severe accidents in terms of numbers of accidents and fatality. Since 2003, 50kph 90degree side crash test has been initiated as a safety standard with EuroSID-1 at the first stage and also same time 55kph impact speed test has been conducted as a part of KNCAP program. Currently only EuroSID-2 is accepted as a regulatory tool for vehicle certification and KNCAP. In order to make use of WorldSID of KNCAP in the distant futuer the tests with WorldSID is conducted experimentally.

The Method of Change Impact Analysis for Railway Signaling S/W (열차제어 S/W 변경영향 분석을 위한 방법 연구)

  • Jo, Hyun-Jeong;Hwang, Jong-Gyu
    • Proceedings of the KSR Conference
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    • 2009.05a
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    • pp.2044-2049
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    • 2009
  • Recent advances in computer technology have brought more dependence on software to railway signaling systems. Hence, the safety assurance of the vital software running on the railway signaling system is very critical task and yet, not many works have been done. While much efforts have been reported to improve electronic hardware's safety, not so much systematic approaches to evaluate software's safety. In this paper, we suggested an automated analysis tool for S/W change impact in railway signaling system, and presented its result of implementation. The analysis items in the implemented tool had referred to the international standards in relation to the software for railway signaling system, such as IEC 61508 and IEC 62279. In these international standards, 'change impact analysis' for railway signaling system S/W has to be required mandatorily. The proposed tool can be utilized at the assessment stage and also the software development stage.

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Analysis on the Factors Affecting the Results of Full Frontal Barrier Impact Test (고정벽 정면충돌시험 결과에 미치는 요인 분석)

  • Lim, Jaemoon
    • Journal of Auto-vehicle Safety Association
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    • v.8 no.3
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    • pp.5-9
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    • 2016
  • The objective of this study was to find the factors affecting the results of full frontal barrier impact test for the NCAP (New Car Assessment Program). To find the factors, the frontal NCAP test results of the NHTSA (National Highway Traffic Safety Administration) were utilized. The three tested vehicle were same model year. It was observed the second peak value of barrier force affected the occupant injury risk. As the second peak value of the barrier force increases, the injury risk of the driver side occupant increases as well.

A Survey on Cognition Levels of Consumers and Producers for Product Liability (제조물책임에 대한 소비자와 생산자의 인식수준에 관한 연구)

  • Kim Jin Tae;Jeon Young Rok
    • Journal of the Korea Safety Management & Science
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    • v.7 no.3
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    • pp.109-120
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    • 2005
  • A company is liable for its products and has the responsibility to make good on any loss or damage incurred by the user of its product. The purpose of the Product Liability Act(PLA) is to protect consumers against damage caused by defective products, and contribute to the safety of the citizen's life and the sound development of the national economy by regulating the liability of manufacturers, etc. for damages caused by the defectiveness of their products. In this study, the cognition levels of consumers and producers for PLA were surveyed. The cognition levels of four factors of acknowledgement, comprehension, necessity and impact for PLA were assessed. The results were as follows : i) Acknowledgement and comprehension levels of consumer were assessed low but they assessed necessity and impact of PLA high; ii) Producers assessed necessity and impact of PLA higher than their acknowledgement and comprehension levels; iii) Overall cognition levels of producers were higher than those of consumers.

A Study on the Analysis of Internal and External Factors of Software Threat Elements (소프트웨어 위협 요소의 내부적·외부적 요인 분석에 관한 연구)

  • Lee Eun Ser
    • The Transactions of the Korea Information Processing Society
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    • v.13 no.6
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    • pp.278-283
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    • 2024
  • When implementing software, there can be side effects that pose a threat to human life. Therefore, it is necessary to measure the impact of software on safety and create alternatives to mitigate and prevent threats. To conduct a software safety assessment to measure the impact of threat factors, the following components are necessary. This paper aims to classify the threat factors of software into internal and external factors and quantitatively demonstrate the impact of these threat factors.

Analysis of Impact on Disaster Prevention Capability of Residents in Resident Participation Safety Improvement Project -Focused on Project of Creating a Safety Village in Sindeok, Daegu- (주민참여형 안전개선사업이 주민방재역량에 미치는 영향분석 -대구 신덕 안전마을 만들기 사업을 중심으로-)

  • Yoon, Sanghoon;Park, Sosoon
    • Journal of the Society of Disaster Information
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    • v.16 no.4
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    • pp.758-767
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    • 2020
  • Purpose: The purpose of this study is to analyze the impact of disaster prevention capability of residents according to before and after resident participation safety improvement project and to present implication. Method: The difference in disaster prevention capability of residents before-after project was compared and analyze using the independent sample t-test. Result: As a result of analysis, it was found that the resident participation safety improvement project had an effect on the disaster prevention capability of residents before-after project. Among them, the parts related to degree of preparation of evacuation and organizational disaster prevention capability were found to have a positive effect Conclusion: When promoting a resident participation safety improvement project, it is necessary to explore and consider various ways to improve the disaster prevention capability of residents and regions.

Effect of Changing the Side Impact Dummy from EuroSID-1 to EuroSID-2 in the KNCAP Side Impact Evaluation (EuroSID-1에서 EuroSID-2로의 인체모형 변경이 KNCAP 측면충돌안전성 평가에 미치는 영향 연구)

  • Lim, Jae-Moon;Jung, Geun-Seup
    • Transactions of the Korean Society of Automotive Engineers
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    • v.15 no.5
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    • pp.125-132
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    • 2007
  • In order to provide consumers with safety informations of vehicles according to the Korean New Car Assessment Program(KNCAP), the evaluation results and the star ratings of 21 vehicles for the side impact tests have been reported since 2003. Now, the KNCAP considers changing the side impact dummy from EuroSID-1 to EuroSID-2 near future. The rib deflection of EuroSID-2 is 20-30% higher than that of EuroSID-1 because of the removal of "Flat Tops" effect. In this study, the effect of changing the side impact dummy from EuroSID-1 to EuroSID-2 in the KNCAP side impact evaluation is estimated through the previous KNCAP evaluation results. The results show that the decrease of the star ratings would be one star($\bigstar$) approximately.