• Title/Summary/Keyword: impact failure

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A critical comparison of reflectometry methods for location of wiring faults

  • Furse, Cynthia;Chung, You Chung;Lo, Chet;Pendayala, Praveen
    • Smart Structures and Systems
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    • v.2 no.1
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    • pp.25-46
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    • 2006
  • Aging wiring in buildings, aircraft and transportation systems, consumer products, industrial machinery, etc. is among the most significant potential causes of catastrophic failure and maintenance cost in these structures. Smart wire health monitoring can therefore have a substantial impact on the overall health monitoring of the system. Reflectometry is commonly used for locating faults on wire and cables. This paper compares Time domain reflectometry (TDR), frequency domain reflectometry (FDR), mixed signal reflectometry (MSR), sequence time domain reflectometry (STDR), spread spectrum time domain reflectometry (SSTDR) and capacitance sensors in terms of their accuracy, convenience, cost, size, and ease of use. Advantages and limitations of each method are outlined and evaluated for several types of aircraft cables. The results in this paper can be extrapolated to other types of wire and cable systems.

Nonlinear dynamic behavior of Pamukcay Earthfill Dam

  • Terzi, Niyazi U.;Selcuk, Murat E.
    • Geomechanics and Engineering
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    • v.9 no.1
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    • pp.83-100
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    • 2015
  • Water and energy supplies are the key factors affecting the economic development and environmental improvement of Turkey. Given their important role and the fact that a large part of Turkey is in seismically active zones dams should be accurately analyzed since failure could have a serious impact on the local population environment and on a wider level could affect the economy. In this paper, a procedure is proposed for the static, slope stability, seepage and dynamic analysis of an earth dam and the Pamukcay embankment dam. The acceleration time history and maximum horizontal peak ground accelerations of the $Bing\ddot{o}l$ (2003) earthquake data was used based on Maximum Design Earthquake (MDE) data. Numerical analysis showed that, the Pamukcay dam is likely to experience moderate deformations during the design earthquake but will remain stable after the earthquake is applied. The result also indicated that, non-linear analysis capable of capturing dominant non-linear mechanism can be used to assess the stability of embankment dams.

Research on the mechanical properties of membrane connections in tensioned membrane structures

  • Zhang, Yingying;Zhang, Qilin;Li, Yang;Chen, Lu
    • Structural Engineering and Mechanics
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    • v.49 no.6
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    • pp.745-762
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    • 2014
  • As an important part, the connections generally are important for the overall behavior of the structure and the strength and serviceability of the connection should be ensured. This paper presents the mechanical properties of membrane connections in tensioned membrane structure. First, the details of common connections used in the membrane structure are introduced. Then, the common connections including membrane seam, membrane-flexible edge connection and membrane-rigid edge connection are tested and the corresponding failure mechanisms are discussed. Finally, the effects of connection parameters on the connection strength are investigated and proper connection parameters are proposed. The strength reduction factors corresponding to different connection types are proposed, which can be references for the design and analysis of membrane structures.

A Study on Influences of Crack Morphology Variables (균열형상변수의 영향 고찰)

  • Park, Won-Bae;Lee, Young-Shin
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.324-329
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    • 2004
  • In this study, an application of crack morphology variables in the Leak-Before-Break(LBB) evaluation for nuclear piping systems is investigated, including influences on the leakage crack size and crack instability loads. The crack surface roughness and the number of flow turns as a function of the crack opening displacement are applied to LBB evaluations for KSNP pressurizer surge line, for which fatigue and stress corrosion cracking are considered as failure mechanisms. As a result, there would be a significant impact on safety margins to acceptance criteria for the surge line if crack morphology variables are applied additionally to the current regulatory guide without re-analyses for justification of safety factors being applied on the leakage crack size and piping loads for evaluations.

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The Optimal Release Time in Cost Model Using PCLS Model

  • Song, Kwang Yoon;Chang, In Hong;Choi, Min Su;Lee, Da Hye
    • Journal of Integrative Natural Science
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    • v.9 no.3
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    • pp.206-214
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    • 2016
  • The basic goal of software development is to produce high quality software at low cost. Therefore, when to stop software testing and release the software product is a significant point in the software development. The software cost model is an effective tool used to help software developers control costs and determine the release time. In this paper, we discuss the cost model to apply all 6 models with consideration of time to remove errors, cost of removing each error and risk cost due to software failure. We show the impact of cost coefficients and parameter values on the expected total cost by changing the values and comparing the optimal release times.

Evaluation of Damage from Reclosing Scheme for Power Transfromer (재폐로방식이 전력용 변압기에 미치는 영향 평가)

  • O, Jeong-Hwan;Yun, Sang-Yun;Im, Seong-Jeong;Kim, Jae-Cheol
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.48 no.3
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    • pp.177-183
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    • 1999
  • This paper presents how to evaluate the transformer damage caused by reclosing scheme at the distribution substation. We describe a quantitative relationship between the reclosing scheme and the number of fault current flowing through transformer wsing the probability of a reclosing success/failure. The transformer damage from reclosing scheme is presented using a weight function and a damage function. A weight function is associated with the number of reclosing attempts and the reclosing deadtime to consider cumulative stress caused by reclosing scheme. A damage function is associated with a transformer impact ratio and a transformer functional life. In the case study, the transformer damage is simulated for the probability of a reclosing success. And the evaluation of transformer damage using KEPCO's operation data is performed.

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The Fracture Behavior Analysis in Concrete Quay Deck Subjected to Collision of Ship (선박충돌에 의한 콘크리트 안벽의 파괴거동분석)

  • Lee, Rae-Chul;Yhim, Sung-Soon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.1 no.1
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    • pp.75-87
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    • 1997
  • To study the behavior a deck when it was collide with the ship approaching to the deck to berth, it was analyzed the effect zone by the ship collision which consists of deck slab and PC piles of the quay. The numerical technique is used to simulate the behavior of the deck when the ship hit the expansion joint of deck between the deck slabs. The failure behavior and zone of the deck are determinated by the comprehensive numerical study. The impact energy by the ship is also evaluated. It is concluded that these numerical analysis gave a reasonable estimation of the remedial area of the deck damaged by ship collision.

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A comparison study on color correction for high-definition video in digital post-production (디지털 후반작업에서 고화질 영상표현을 위한 색보정(color correction) 비교연구)

  • Oh, Moon Seock;Won, Jong Wook;Lee, Yun Sang
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.9 no.4
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    • pp.167-175
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    • 2013
  • This study is the process of making high-definition TV broadcast color correction affects the end result comparison is focus on implement through study. In the production process and the impact on the color Correction in the video as an study for UHD, 4K, 6K video production workflow improvement of an effective program in the present and time and cost in the post production process, color correction for the final video through the production and overcome the failure of further in-efficient color correction study will help you to solve the problem. This study is the color changes over the course of the final video to see how much influence color correction of post-production. Color correction using a program of courses in Visual quality, regularly presented the possibility to retain and make on high definition video production post-production process for color correction method is utilized as the basis of study.

Design of Hardward Diagnostic System for Reactor Internal Structures Using Neutron Noise (중성자 신호이용 원자로 내부 구조물 감시시스템 하드웨어 설계)

  • Park, Jong-Beom;Park, Jin-Ho;Hwang, Choong-Hwan;Kim, Soo-Hong
    • Proceedings of the KIEE Conference
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    • 2001.07d
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    • pp.2166-2168
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    • 2001
  • Reactor Noise is defined as the fluctuations of measured instrumentation signals during full-power operation of reactor which have informations on reactor system dynamics such as neutron kinetics. The Reactor internal structures which consist of many complex components are subjected to flow-induced vibration due to high temperature and pressure in reactor coolant system. The above flow-induced vibration causes degradation of structural integrity of the reactor and may result in loosing mechanical binding component which might impact other equipment and component or cause flow blockage. It is important to analyze reactor noise signal for the early detection of potential problem or failure in order to diagnosis reactor integrity in the point of view of safety and plant economics. Detailed design of hardware diagnostic system reactor internal structures using neutron noise(RIDS).

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Up-gradation in Human Resource Management Practices for the Biotech Industry in India

  • Kumari, Neeraj
    • The Journal of Asian Finance, Economics and Business
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    • v.2 no.2
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    • pp.27-34
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    • 2015
  • The 21st century belongs to biotechnology as it made profound impact in the field of health, food, agriculture and environmental protection. India's biotechnology industry is poised to record substantial growth, perhaps even overtake the robust IT industry. The objectives of the study are to determine the existing HR practices in Biotech Industry and to understand the need for the up gradation in existing HR Policies. Conclusive and descriptive research design has been used. Data is collected from 122 employees in 23 companies of Biotech Industry. It was found that Biotechnology companies require managers with unique qualities. The lack of solid managerial training and the associated risk of failure often have long-term consequences for the careers of research professionals. The efforts to achieve excellence through a focus on learning, quality, teamwork, and reengineering are driven by the way organizations get things done and how they treat people. Biotech industry is trying to establish itself in India for last one decade but is not showing any phenomenal growth because they still do not valuing their human resource as much they should be.