• Title/Summary/Keyword: Damage range

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A Study on the Damage Range According to Leakage Scenarios in Natural Gas Pipeline of LNG Fueled Ship (LNG 추진선의 천연가스 배관에서 누출 시나리오에 따른 피해범위에 관한 연구)

  • Lee, Yoon-Ho
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.26 no.4
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    • pp.317-326
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    • 2020
  • In this study, damages caused by flash fire, overpressure, and thermal radiation based on the sizes of leak holes were evaluated using the areal location of hazardous atmospheres when natural gas leaked owing to the damage of pipeline in a LNG fueled ship. In addition, environmental variables (wind speed, atmospheric temperature, and atmospheric stability) and process variables (pipe pressure and pipe length) were classified to analyze the damage impact ranges caused by various scenarios. From the results, the damage range caused by the environmental variables was the largest, followed by overpressure and thermal radiation. Additionally, for the process variables, regardless of the pressure, length, or size of the leak holes, the damage range attributed to flash fire was the most significant, and the damage range was high in the order of overpressure and thermal radiation, similar to the environmental variables. The larger the size of the leak holes, the higher the values of the environmental and process variables, and the higher the damage range caused by jet fire compared to the environmental variables.

A Random Walk Model for Estimating Debris Flow Damage Range (랜덤워크 모델을 이용한 토석류 산사태 피해범위 산정기법 제안)

  • Young-Suk Song;Min-Sun Lee
    • The Journal of Engineering Geology
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    • v.33 no.1
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    • pp.201-211
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    • 2023
  • This study investigated the damage range of the debris flow to predict the amount of collapsed soil in a landslide event. The height of the collapsed slope and the distance traveled by the collapsed soil were used to predict the total trajectory distance using a random walk model. Debris flow trajectory probabilities were calculated through 10,000 Monte Carlo simulations and were used to calculate the damage range as measured from the landslide scar to its toe. Compiled information on debris flows that occurred in the Cheonwangbong area of Mt. Jirisan was used to test the accuracy of the proposed random walk model in estimating the damage range of debris flow. Results of the comparison reveal that the proposed model shows reasonable accuracy in estimating the damage range of debris flow and that using 10 m × 10 m cells allows the damage range to be reproduced with satisfactory precision.

Damage Characteristics of Quasi Isotropic Composite Laminates Subjected to Low Velocity Impact (준등방성 복합적층판의 저속충격에 의한 손상특성)

  • Kim, J.H.;Jeon, J.C.
    • Journal of the Korean Society for Precision Engineering
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    • v.14 no.6
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    • pp.135-141
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    • 1997
  • Low velocity impact test and compressive residual strength test after impact were performed by using Hercules AS4/3501-6[45/0/-45/90]$_{2s}$ laminated plate to investigate the low velocity impact damage behavior and the post-impact strength degradation on orthotropic composite laminate plate. Due to the lateral impact losd, the load path showed "" shape according to the laminate central deflection. Damage in a laminate occurs by inclined matrix crack at the damage initiation load stage and vertical matrix crack, occurs on the outer surface. Evaluating the compressive residual strength after the low velocty impact test, it could be found that there is a transient range where the compressive residual strength drop suddenly in the initial damage which is in the matrix crack range and the initial delamination area. is in the matrix crack range and the initial delamination area.

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Overview of the Environmental Damage, Property Loss, and Health Impairment of Residents around a US Air Force Firing Range (미국 공군 사격장 지역주민의 환경, 재산 및 건강피해)

  • Lim, Hyun-Sul
    • Journal of Environmental Health Sciences
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    • v.37 no.3
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    • pp.173-181
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    • 2011
  • Koo-ni Firing Range in Maehyang-ri consisted of a firing range around 'Nong-sum' and a land-based firing range in the nearby coastal area. From 1951, when the US Air Force began field firing, residents of Maehyang-ri suffered damage to health, environment, life and property due to 54 years of field firing and noise. The purpose of this article is to provide an overview of the environmental damage, property loss, and health impairment by reviewing literature and related lawsuits. Environmental damage, the destruction of coastal fisheries and wetlands, would be a result of heavy metal contamination of soil. Fishing restrictions and the confiscation of farmlands caused financial hardship. Errant bombings led to the loss of life and property, including buildings and livestock. As a result, residents repeatedly sued the Republic of Korea for damages. The court decided partially in favor of the plaintiffs. Finally, Koo-ni firing range was closed down in 2005. Through the literature review, it is presumed that the noise caused hearing problems, hypertension, and mental illness. Since earlier studies were confined to a small fragment of the damage, additional studies focused on chronic health hazards are needed.

Study on Levee Visual Inspection Information System Building Using Mobile Technology

  • Kang, Seung-Hyun;Lee, Jong-Min
    • Journal of the Korea Society of Computer and Information
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    • v.21 no.6
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    • pp.71-76
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    • 2016
  • In this paper, we propose the mobile visual inspection information system using DGPS and portable range finder for levee safety inspection. Instead of existing visual inspection management method that is stored hand-written data, this system is designed to manage directly the visual inspection information using mobile devices in the field of levee. And through extracting accurate DGPS coordinates information about damage location of levee, this system is developed to ensure efficiency for the main task arising from the levee site such as inspection, maintenance and reinforcement. Furthermore, when damage has occurred at the point that inspector is not able to approach, this system can record the damage site data correctly, by converting data such as position, orientation and height of the damage point into the World Geodetic System coordinates. The position, orientation and height data was extracted automatically through the DGPS and portable range finder. And by applying the augmented reality method, this system was implemented for inspector to revisit the point of damage easily in order to perform the management, maintenance and reinforcement of the levee later.

A Study on the Range of Damage Effects of Benzene Leakage Accidents using the KORA Program (KORA 프로그램을 활용한 벤젠 누출사고 피해영향범위에 관한 연구)

  • Cha, Jeong-Min
    • Fire Science and Engineering
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    • v.33 no.4
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    • pp.112-120
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    • 2019
  • Benzene is a class 4 hazardous material according to the Act on the Safety Control of Hazardous Substances. This study qualitatively evaluated the damage size of a "toxic" accident and "pool fire" accidents based on benzene in a virtual scenario of a fire and leakage accident during unloading at a port facility. The KORA program was used as an evaluation method, which is supported as a universal program by the National Institute of Chemical Safety. The range of damage effects of a benzene-induced fire and leakage accident was predicted. In the case of toxic damage range, the accident's damage effect range for the "worst case scenario" was reduced by up to 5.11% with a decrease in the size of the leakage hole. In the case of the leakage time, the damage effect range increased to 145.12% with a 10 min leakage time compared to that of a 5 min leakage time and went up to 20 min (212.29%) with a 20 min leakage time. In the case of pool-fire-induced damage, the damage effect range by radiant heat in the "worst case scenario" was 228.8 m in radius from the center of the handling facility. In the "alternative scenario," the damage effect range by radiant heat was reduced by up to 8.26% compared to that in the "worst case scenario" since the size of the leakage hole was decreased by reducing the cross-sectional area of the pipe.

Provenance and Concept of 10 Symptoms of Para-cold Damage(類傷寒) from Yixuerumen(醫學入門) (『의학입문(醫學入門)·상한편(傷寒篇)』 유상한(類傷寒) 병증(病症) 10종의 유래와 개념에 대한 연구)

  • Jo, Hak-jun
    • Journal of Korean Medical classics
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    • v.29 no.4
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    • pp.17-36
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    • 2016
  • Objectives : This paper seeks to study the provenances of 10 Symptoms of Para-cold damage from Yixuerumen, and discovers the rationality and originality of para-cold damages recognized by Li Chan. Methods : The paper looks through the books referenced by Yixuerumen to investigate the source text for Yixuerumen's Para-cold Damage chapter, and the contents of the referenced books will be compared to that of Yixuerumen. Results : The sources of the 10 symptoms of para-cold damage from Yixuerumen Chapter of Cold Damage can be traced to Leizhenghuorenshu (expectoration, indigestion, rising temperature due to lack of energy, and beriberi), Wang Zhen's Shanghanzhengzhimingtiao Xinzengxuleishanghansizheng(the infection in a boil, blood sattis, caused overexertion, and pox), and Liu Chun's Yujiweiyi's chapter on Common Cold. Here, Li Chan made his own addition of internal damage and damage of overworking. Li Chan seems to have considered para-cold damage not as a type of cold damage but as a "concept relative to the broader range of cold damage." In reflection of this understanding, Li Chan limited the number of categories to ten in accordance with the developmental trace leading from Leizhenghuorenshu to Shanghanzhengzhimingtiao. When we understand para-cold damage as a "concept relative to the narrower range of cold damage," it could be used as a mean as for "Wenbin diagnosis," but Yixuerumen's para-cold damage is only utilized for the "diagnosis of a broader concept of cold damage." Conclusions : Li Chan deserves credits for his academic rationality and originality displayed by the method he used to form para-cold damages where he used real cold damage and para-cold damage as principles, by the division of para-cold damage symptoms into ten provenances, by the creation of the concept of para-cold damage, and by his broad collection of prescription and treatment corresponding to each type.

Development of Modified Creep-Fatigue Damage Model for High Temperature Life Prediction (고온 수명평가를 위한 수정 크립-피로 손상모델의 걔발)

  • Park, Jong-Joo;Seok, Chang-Sung;Kim, Young-Jin
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.20 no.11
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    • pp.3424-3432
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    • 1996
  • For mechanical system operating at high temperature, damage due to the interaction effect of creep and fatigue plays an important role. The objective of this paper is to develop a modified creep-fatigue damage model which separately analyzes the pure creep damage for hold time and the creep-fatigue interaction damage during startup and shutdown period. The creep damage was calculated by the general creep damage equation and the creep-fatigue interaction damage was calculated by the modified equation which is based on the frequency modified strain range method with strain rate term. In order to verify the proposed model, a service of high temperature low cycle fatigue tests were performed. The test specimens were made from inconel-718 superalloy and the test parameters were wave shape and hold time. A good agreement between the predicted lives based on the proposed model and experimentally obtained ones was observed.

A Study on Improvement of Damage Impact Range Assessment for Field-Based Response Against Chemical Terrorism and Accidents (현장 중심의 화학테러·사고 대응을 위한 피해 영향 범위 평가 개선 방안 연구)

  • Lee, Deok-Jae;Song, Chang Geun
    • Journal of Convergence for Information Technology
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    • v.10 no.8
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    • pp.127-136
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    • 2020
  • Chemical terrorism and accidents using chemicals are continuously occurring and attempted in and out of the country. In Korea, the National Institute of Chemical Safety affiliated with Ministry of Environment employs the CARIS(Ver. 2018) to assess the damage impact range for field-based response against chemical terrorism and accidents. However, the current version of CARIS can not consider the effects of closed space such as indoor and underground, so it is difficult to provide accurate evaluation results for damage impact range required for field response, on top of the limited information available. The limitations and directions for improvement were studied by comparing and reviewing the evaluation results of the damage impact range obtained by driving CARIS (Ver. 2018) and the domestic and foreign literature. Proposed improvements also included the direction of information provided to residents, including the need to build modeling for special points, such as underground, indoor, etc., and on-site response personnel. It is expected that through the continuous supplementation and correction of CARIS, chemical terrorism and accident response capability system will be advanced further.

Impact Range Comparative Analysis of BLEVE by Gas Leakage According to LPG Main Components (LPG 주성분에 따른 누출 폭발 피해 영향범위 비교분석)

  • Soo-Hee Lim;Su-Yeon Son;Ha-Sung Kong
    • Journal of the Korea Safety Management & Science
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    • v.26 no.3
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    • pp.51-57
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    • 2024
  • The purpose of this study is to compare and analyze the impact range of explosion damage due to gas leaks at LPG filling stations, focusing on propane and butane, which are components of vehicle LPG. The scenarios were designed based on the explosion incident at an LPG filling station in Gangwon-do, where an actual gas leak accident occurred, resulting in Scenario I and Scenario II. The ALOHA program, developed by the U.S. National Oceanic and Atmospheric Administration (NOAA), was used as the tool to analyze the impact range of the explosion damage for both substances. The results of the study indicated that, under identical conditions, propane had a wider impact range of damage than butane. This is presumed to be due to the greater explosion energy of propane, attributable to its physicochemical properties. Therefore, when preparing for LPG leak accidents, measures for propane need to be prioritized. As safety measures for propane, two suggestions were made to minimize human casualties. First, from a preventive perspective, it is suggested to educate workers about propane. Second, from the perspective of response measures and damage minimization, it is suggested to thoroughly prepare emergency evacuation and rescue plans, evacuation routes, designated shelters, and emergency response teams. This study compares and analyzes the impact range of radiative heat damage based on LPG components. However, hazardous accidents are critically influenced by the type of leaking substance, the form of the leak, and meteorological factors affecting the diffusion pattern of the substance. Therefore, for future research, it is proposed to model various leakage scenarios for the same substance to conduct a comprehensive risk assessment.