• Title/Summary/Keyword: estimation of damages

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Development of Dynamic Frequency Monitoring Software for Wide-Area Protection Relaying Intelligence (광역 보호계전 지능화를 위한 동적 주파수 모니터링 S/W 개발)

  • Kim, Yoon-Sang;Park, Chul-Won
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.61 no.4
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    • pp.174-179
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    • 2012
  • The social and economic level of damages might be highly increased in the case of wide-area black-outages, because of heavy dependence of electricity. Therefore, the development of a wide-area protection relay intelligence techniques is required to prevent massive power outages and minimize the impact strength at failure. The frequency monitoring and prediction for wide-area protection relaying intelligence has been considered as an important technology. In this paper, a network-based frequency monitoring system developed for wide-area protection relay intelligence is presented. In addition, conventional techniques for frequency estimation are compared, and a method for advanced frequency estimation and measurement to improve the precision is proposed. Finally, an integrated monitoring system called K-FNET(Korea-Frequency Monitoring Network) is implemented based on the GPS and various energy monitoring cases are studied.

Study on Applicability of Design Flood Estimation Methods in Creeks (소하천 설계홍수량 추정모형의 적용성 검토)

  • Kim, Yangsu;Lee, Byongju;Kim, Junho
    • Proceedings of the Korea Water Resources Association Conference
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    • 2004.05b
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    • pp.163-167
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    • 2004
  • Creeks, defined by creek's improvement law, have strong localities in the flow characteristics and environmental condition. During the recent ten-years, lots of flood damages have occurred rather in the creeks. However, quantity and stream design information are poor while the national-class and local-class streams have sufficient. This causes a problem on improving the safety from flood. This study focuses on assessment of practical applicability for design flood estimation models. For this, Rational formula, Clark's model and Nakayath synthetic unit hydrograph method are estimated by data of the creek comprehensive improvement plan report, etc.

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Fatigue Life Assessment and Stress History Measurement of Steel Truss Railway Bridge occurring Fatigue Damages (피로손상이 발생한 강트러스철도교의 응력이력계측 및 피로수명평가)

  • 장동일;경갑수;조광현;홍성욱
    • Journal of the Korean Society of Safety
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    • v.15 no.1
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    • pp.132-139
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    • 2000
  • In this study, the fatigue life assessments of steel railway bridge in Japan National Railway were carried out. This railway bridge has been under in service from 1957, and fatigue damages were occurred at bead toe of upper part of vertical stiffeners of stringers, bead toes of scallop in lower part of vertical stiffeners in stringers and crossings of cross beams and stringers. From this study, a series of field tests were carried out by stress history measurement about above mentioned points. And as a results of stress histogram analysis, cummulative fatigue damage rate and fatigue life of these members should be calculate quantitatively. And from this estimation technique, cummulative fatigue damage rate and fatigue life of this railway bridge were strongly affected in passing tonage every year and the histories of live load.

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Optimization of collaborative risk management in supply chain management (공급사슬경영에서의 협업적 리스크 관리의 최적화)

  • Jeong Jang Hwa;Lee Yeong Hae;Jeong Jeong U
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2002.05a
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    • pp.456-463
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    • 2002
  • Nowadays. risk management in the enterprise is considered as the important activity. Risk management ran be defined as the activity which is the analysis of risk factors related to damages, the estimation of the magnitude of risk, and the determination of investment to protect damage in a company. Initially, risk management was originated in financial areas. But the concept of risk has been expanded in the enterprise. Most companies have extended their activities in various areas. In this tendency, most activities must be considered in supply chain So, risk management must be ronsidered as the concept in the viewpoint of supply chain. The framework of risk management in supply chain and the related mathematical model are represented in this paper. Risk management in supply chain ran provide a positive opportunity not only to protect various damages, but also to improve the relationship between partners.

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Noise Isolation Method at Construction Site (건설공사장 소음방지 대책)

  • Jung, Gab-Cheol
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.940-948
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    • 2000
  • Noise and vibration generated at construction sites become serious issues because of bigger construction projects and growing use of heavy equipment. Especially in downtown construction, noise and vibration easily exceed the legal standards that can suffer the most of surrounding residents. The number of complaints by the residents who are exposed to the noise increases as their consciousness grows. However, the Korean regulations for the construction noise and vibration only present the overall limits for target areas and times zones, and this make it difficult to take effective measures. Also in rural area, disputes between construction sites and residents arise, but the dispute resolution or taking measures are difficult because clear standards concerning cause-and-effect, estimation of effective levels, calculation of damages, and future precautions and examples lack. This paper describes legal standards regarding the noise and vibration and presents judging standards for the physical damages. This paper also introduces example public complaints that happened at Daewoo construction sites to describe the problems in the existing law and further to enable smooth construction progresses by emphasizing the seriousness of public complaints.

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Estimation of Structural Damages by Inverse Modal Perturbation Method (구조물 손상의 추정을 위한 Inverse Modal Perturbation 기법)

  • Min, Jin Ki;Kim, Hyeong Ki;Hong, Kyu Seon;Yun, Chung Bang
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.10 no.4
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    • pp.35-42
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    • 1990
  • A method for the damage assessment of a structure by an inverse modal perturbation technique is studied. The first few natural frequencies and mode shapes of the damaged structure are assumed to be known. Then, the perturbation equation is formulated for the changes of the modal properties due to the stiffness changes. The stiffness changes due to damages are evaluated, using optimization techniques. Example analyses are carried out for several cases of stick models and a truss model. Results indicate that the present method yields very reasonable estimates for the element stiffness changes.

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Damage detection and localization on a benchmark cable-stayed bridge

  • Domaneschi, Marco;Limongelli, Maria Pina;Martinelli, Luca
    • Earthquakes and Structures
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    • v.8 no.5
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    • pp.1113-1126
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    • 2015
  • A damage localization algorithm based on Operational Deformed Shapes and known as Interpolation Damage Detection Method, is herein applied to the finite element model of a cable stayed bridge for detecting and localizing damages in the stays and the supporting steel beams under the bridge deck. Frequency Response Functions have been calculated basing on the responses of the bridge model to low intensity seismic excitations and used to recover the Operational Deformed Shapes both in the transversal and in the vertical direction. The analyses have been carried in the undamaged configuration and repeated in several different damaged configurations. Results show that the method is able to detect the damage and its correct location, provided an accurate estimation of the Operational Deformed Shapes is available. Furthermore, the damage detection algorithm results effective also when damages coexist at the same time at several location of the cable-stayed bridge members.

Development of Flood Damage Estimation Method for Urban Areas Based on Building Type-specific Flood Vulnerability Curves (건축물 유형별 침수취약곡선 기반의 도시지역 침수피해액 산정기법 개발)

  • Jang, Dongmin;Park, Sung Won
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.44 no.2
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    • pp.149-160
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    • 2024
  • Severe casualties and property damage are occurring due to urban floods caused by extreme rainfall. However, there is a lack of research on preparedness, appropriate estimation of flood damages, assessment of losses, and compensation. Particularly, the flood damage estimation methods used in the USA and Japan show significant differences from the domestic situation, highlighting the need for methods tailored to the Korean context. This study addresses these issues by developing an optimized flood damage estimation technique based on the building characteristics. Utilizing the flood prediction solution developed by the Korea Institute of Science and Technology Information (KISTI), we have established an optimal flood damage estimation technology. We introduced a methodology for flood damage estimation by incorporating vulnerability curves based on the inventory of structures and apply this technique to real-life cases. The results show that our approach yields more realistic outcomes compared to the flood damage estimation methods employed in the USA and Japan. This research can be practically applied to procedures for flood damage in urban basement residences, and it is expected to contribute to establishing appropriate response procedures in cases of public grievances.

Development of the Practical System for the Automated Damage Assessment (재해 피해조사 자동화를 위한 실용시스템 구축)

  • Jin, Kyeonghyeok;Kim, Youngbok;Choi, Woojung;Shim, Jaehyun
    • Journal of Korean Society of societal Security
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    • v.1 no.2
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    • pp.73-78
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    • 2008
  • Recently, large scale natural disasters such as floods and typhoons due to climate change have been occurring all over the world causing severe damages. Among the various efforts to reduce and recover damages, recently, advanced information technology and remote sensing techniques are applied in disaster management. In this study, a real-time automated damage estimation system using information technology and spatial imagery was developed to accomplish prompt and accurate disaster damage estimation. This system is able to estimate the damage amounts of public facilities such as roads, rivers, bridges automatically through spatial imageries including ground based digital images, aerial photos, satellite images of disaster sites. Based on these spatial imageries, the damage amounts are analyzed in the Web-GIS based analysis system. Consequently, the digital damage reports such as digital disaster information sheets and damage maps can be made promptly and accurately. This system can be a useful tool to carry out prompt disaster damage estimation and efficient disaster recovery.

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A Study on the Problems in Exercising Buyer's Right to Claim Damages for the Breach of Contract by the Seller in International Sales Contract - Focusing on CISG and UNIDROIT Principles(2010) - (국제물품매매계약에서 매도인의 계약위반에 대한 매수인의 손해배상청구권 행사의 문제점 - CISG와 UNIDROIT Principles(2010)을 중심으로-)

  • Oh, Won Suk;Youn, Young Mi;Lim, Sung Chul
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.58
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    • pp.3-33
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    • 2013
  • The purpose of this paper is to examine the problems in exercising buyer's right to claim damages for the breach of contract by the seller in international sales contract and to suggest reasonable counter-measures. The main contents are as follows: First, this author analyzed the principles of the seller's liability for damages in detail and examined the methods for the calculation of damages on the basis of Arts.74~77. As these articles are found to be insufficient in practical application, this author further examined the UNIDROIT Principles(2004) to confirm whether these Principles can fill the gaps of CISG or not, which turned out their gap-filling functions. Second, this author tried to find any expected problems when the buyer resorts to the right to claim damages in case of the seller's breach of contract including the estimation of damages, the burden of proof, causation, the proof of appropriateness for avoidance, the proof of buyer's obligation to mitigate the loss and so on. The reason is that these problems may cause a lot of difficulties in real business. As result, many buyers have given up their reasonable rights to claim damages so far. Finally, from the buyer's perspective, this author would like to suggest a liquidated damage clause(LD Clause) which gives the buyer to received a specified sum in case of seller's non-performance and/or a demand guarantee(or standby L/C) which guarantees buyer to secure unconditional payment independent of the underlying contract. For these purposes, the buyer should try to insert the LD Clause and/or Guarantee Clause in the contract when the buyer and the seller negotiate the sales contract. Also there are a lot of considerations and limitations in using the LD Clause and the Guarantee Clause in their real business, mainly dependent up bargain power between the seller and the buyer, for which this author promise to examine in detail in the future.

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