• Title/Summary/Keyword: BREACH

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Experimental Study on Influence of Levee Breach Depth on Flood Wave Propagation in Inundation Area (제방붕괴깊이 조건에 따른 제내지 범람홍수파 거동 실험)

  • Yoon, Kwang-Seok
    • Proceedings of the Korea Water Resources Association Conference
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    • 2007.05a
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    • pp.899-903
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    • 2007
  • 본 연구에서는 제방붕괴에 의한 제내지 홍수파 거동 해석의 일환으로 제방붕괴시 제방의 붕괴깊이에 따른 제내지에서의 홍수파의 거동 양상을 수리실험을 통하여 고찰하였다. 다양한 제방붕괴폭과 초기하도수위 및 제방붕괴고 조건에 대해 범람홍수파의 전파속도와 제내지에서의 최대수심의 변화를 실험을 통하여 관찰하였다. 범람홍수파 선단(wave-front)의 이동속도는 동일한 하도수위조건에서는 붕괴고가 높을수록 감소하는 것으로 나타나 제방붕괴시 월류수심 $H_w$가 범람홍수파 전파속도에 영향을 준다는 것을 알 수 있었다. 모든 실험조건에서 최대수심은 일정한 경향을 띠고 있음을 알 수 있었다. 제방인근 지점에서 최대수심이 가장 크게 나타났고, 붕괴부로부터 일정 지점이 지나면 수위가 급격히 감소하여 거리에 관계없이 일정한 최대수심을 유지하는 것을 알 수 있었다. 동일 수위조건이라면 제방붕괴고가 낮을수록 제내지로 유입되는 유량이 증가하여 초기에 제방붕괴부 주위에서 수심이 높아지는 것으로 분석할 수 있다. 실험결과를 이용하여 범람홍수파의 전파속도와 최대수심을 산정하는 식을 무차원변수를 이용하여 제시하였다.

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Feasibility Study on the Development of Alternative Methods for the Treatment of TRISO Fuels

  • Lee Jong-Hyeon;Shim Joon-Bo;Ahn Byung-Gil;Kwon Sang-Woon;Kim Eung-Ho
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2005.06a
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    • pp.352-361
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    • 2005
  • In this study, conventional head-end processes of spent TRISO fuel have been reviewed to develope more effective treatment methods. The main concerns in the TRISO treatment are to effectively separate the carbon and SiC contained in the TRISO particles. The crush-burn scheme which was considered in the early stages of the development has been replaced by the crush-leach process because of $^{14}C$ problems as a second waste during the process. However there are still many obstacles to overcome in the reported processes. Hence, innovative thermomechanical concepts to breach the coating layers of the TRISO particle with a minimized amount of second waste are proposed in this paper and their principles are described in detail.

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A Development of the Recoil Rod Pull Force Measurement System Using the Load Cell with Sleeve (슬리브관을 갖는 로드셀을 이용한 주퇴봉 당김력 계측시스템 개발)

  • Choi, Ju-Ho;Hong, Sung-Soo;Lyou, Joon
    • Journal of Institute of Control, Robotics and Systems
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    • v.7 no.2
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    • pp.152-159
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    • 2001
  • This paper presents a development of the recoil rod pull force measurement system suing the load cell with a sleeve normally available in the recoil system test. The commercial load cell cannot be used in the test of recoil system floating the breach contact point freely in the air. The load cell is designed and manufactured to meet the recoil system test condition. Theoretical analysis and experimental results show that the accuracy of the developed measurement system is within $\pm$0.5%. We notice that the measurement technique proposed in this paper is accurate and useful in the recoil rod pull force measurement of the recoil system.

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The Relationship between Airway Inflammation and Exacerbation in Chronic Obstructive Pulmonary Disease

  • Perng, Diahn-Warng;Chen, Pei-Ku
    • Tuberculosis and Respiratory Diseases
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    • v.80 no.4
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    • pp.325-335
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    • 2017
  • Chronic obstructive pulmonary disease (COPD) is associated with abnormal inflammatory response and airflow limitation. Acute exacerbation involves increased inflammatory burden leading to worsening respiratory symptoms, including dyspnea and sputum production. Some COPD patients have frequent exacerbations (two or more exacerbations per year). A substantial proportion of COPD patients may remain stable without exacerbation. Bacterial and viral infections are the most common causative factors that breach airway stability and lead to exacerbation. The increasing prevalence of exacerbation is associated with deteriorating lung function, hospitalization, and risk of death. In this review, we summarize the mechanisms of airway inflammation in COPD and discuss how bacterial or viral infection, temperature, air pollution, eosinophilic inflammation, and concomitant chronic diseases increase airway inflammation and the risk of exacerbation.

Study on the Horizontally Installed Emergency Exit in Apartment Houses (아파트 하향식 피난구에 대한 고찰)

  • Yeo, In-Hwan;Min, Byung-Yeol
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2010.05b
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    • pp.91-93
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    • 2010
  • Recently, the regulation about HEE(horizontally installed emergency exit) established at upper 4story in apartment houses was introduced by revising enforcement degree of Building Act. HEE is a facility for egress to lower story through floor breach and ladder system so that it gives a useful evaquation way directly to an individual household in apartment when they failed to evacuate through the entrance door. HEE may offer an opportunity to optain two way egress path ways instead of evacuation space at balcony and through path way to adjacent household in building and that might be an big strengh. but it needs to guarantee for against the crime, getting detailed reviews for being security and supplementation of fire test methods.

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Modelling of concrete structures subjected to shock and blast loading: An overview and some recent studies

  • Lu, Yong
    • Structural Engineering and Mechanics
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    • v.32 no.2
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    • pp.235-249
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    • 2009
  • The response of concrete structures subjected to shock and blast load involves a rapid transient phase, during which material breach may take place. Such an effect could play a crucial role in determining the residual state of the structure and the possible dispersion of the fragments. Modelling of the transient phase response poses various challenges due to the complexities arising from the dynamic behaviour of the materials and the numerical difficulties associated with the evolving material discontinuity and large deformations. Typical modelling approaches include the traditional finite element method in conjunction with an element removal scheme, various meshfree methods such as the SPH, and the mesoscale model. This paper is intended to provide an overview of several alternative approaches and discuss their respective applicability. Representative concrete material models for high pressure and high rate applications are also commented. Several recent application studies are introduced to illustrate the pros and cons of different modelling options.

A Study on Exemption of Insurer for a Long Period Laid-up Fishing Vessel (장기 계류 어선에 대한 보험자의 면책에 관한 연구)

  • Park, Yong-Sub;Cha, Cheol-Pyo
    • Journal of Fisheries and Marine Sciences Education
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    • v.5 no.2
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    • pp.110-118
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    • 1993
  • A squid gill-net fishing vessel Jayueoroho which was being insured ITC-Hulls and was laid up long period illegally under the condition of unmanned in the Pert of Kamcheon. On 30, March, 1993, the fishing vessel moved out toward the high sea by assistance of two tugboats, 12 miles southeast from Teajongdae, to discharge sewage. At that time the shipowner, the skipper, chief engineer and two labourers were boarding, and a fire was broken out by electric leakage at sea. For all their efforts of fire-fighting operation the fishing vessel foundered with explosion. In this case, she had been breached the warranties of legality, especially Korean maritime acts concerned, and the warranties of seaworthiness(MIA 39(5)) as attributable cause because of unmanned on board by wilful misconduct of the insured. Therefore it is prima facie evidence that the insurer is not liable for any loss attributable to the wilful misconduct and breach of warranties of the insured in MIA 1906.

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Role Based Smart Contract For Data sharing

  • Joachim, Kweka Bruno;Rhee, Kyung-Hyune
    • Proceedings of the Korea Information Processing Society Conference
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    • 2018.10a
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    • pp.235-237
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    • 2018
  • The Internet has allowed many things to move fast, including sharing of data, files and others within a second. Many domains use applications range from IoT, smart cities, healthcare, and organizations to share the data when necessary. However, there are some challenges faced by existing systems that works on centralized nature. Such challenges are data breach, trustiness issue, unauthorized access and data fraud. Therefore in this work, we focus on using a smart contract which is used by blockchain platform and works on decentralized form. Furthermore, in this work our contract provides an access to the file uploaded onto the decentralized storage such as IPFS. By leveraging smart contract-role based which consist of a contract owner who can manage the users when access the certain resources such as a file and as well as use of decentralized storage to avoid single point of failure and censorship over secure communication channel. We checked the gas cost of the smart contract since most of contracts tends to be a high cost.

Hydraulic Experiments of Flood Wave Propagation Due to Levee Breach in Inundation Area by Variation of Froude Number (Froude 수 변화에 따른 제방붕괴 범람홍수파의 전파 수리모형실험)

  • Kim, Soo-Young;Lee, Ji-Hun;Jung, Seok-Il;Lee, Seung-Oh
    • Proceedings of the Korea Water Resources Association Conference
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    • 2012.05a
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    • pp.148-148
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    • 2012
  • 제방의 붕괴는 전체 수공구조물 중 70%를 차지하고 있으며, 그 중 월류에 의한 피해가 40%로 가장 많은 비율을 차지하고 있다. 제방을 월류하여 제내지로 유입되는 붕괴유량은 높은 속도로 제내지로 전파된다. 제방붕괴로 인한 피해를 줄이기 위해서는 이러한 붕괴파의 거동에 대한 연구가 필요하다. 기존의 연구들에서는 제방의 붕괴를 수문의 개방으로 가정하여 제내지 유입을 재현하였다. 본 연구에서는 제방의 규격은 높이 3 m, 정부폭 3 m, 사면경사가 1:2인 제방에 대해서 1/10 축척으로 수리모형실험을 실시하였으며 제방의 붕괴부를 모래를 축조하여 이동상으로 제작하였고 이동상 제방의 길이는 4 m이다. 제방에 월류를 유도하여 붕괴를 유발하였으며 홍수파가 제내지로 유입되는 속도 및 경향을 기록하였다. 제내지는 길이 6 m, 폭 6 m로 수평하게 제작하였다(그림 1 참조). Froude 수 변화에 따라 제내지로 유입되는 범람홍수파의 전파 경향을 분석하였으며 그 결과 Froude 수가 클수록 선단 홍수파의 방향이 하류방향으로 전파되는 경향을 나타냈다.

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Exploring the Association between Board Structure and Information Security Breaches

  • Hsu, Carol;Wang, Tawei
    • Asia pacific journal of information systems
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    • v.24 no.4
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    • pp.531-557
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    • 2014
  • Although the area of information security planning and management has gained an increased attention, not much discussion was available on the role and the impact of the board members towards a firm's security management and governance decisions. In this research, we draw on corporate governance and the organizational demography literature to conduct an exploratory empirical study on the association between the board structure of a firm and the possibility of information security breaches. Our results show that the board size, the average age/tenure and the heterogeneity of age could reduce the possibility of security breaches while the proportion of independent directors and the heterogeneity of tenure could increase it. Our findings shed lights on the important role played by the board when managing information security risks in organizations.