• Title/Summary/Keyword: check

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New Paradigm on the Safety Check of Concrete Gravity Dams at Earthquake (중력식댐의 지진시 안전검토에 대한 뉴 패러다임)

  • Bae, Jung-Joo;Kim, Yon-Gon;Lee, Jee-Ho
    • Journal of the Korean Society of Safety
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    • v.24 no.6
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    • pp.86-92
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    • 2009
  • In the safety check of gravity dams at earthquake, there have been two types of analysis conducted simultaneously; one is stability analysis and the other stress analysis. But those are essentially the same calculation other than the former considers the dams rigid, while the latter considers the dams' dynamic characteristics which results in the amplification of response acceleration on the upper part of dam body. In this paper, the identity of those two methods is verified by example calculation in terms of stability check of gravity dam. It can be concluded that if stress analysis were performed, stability check of gravity dam could be accomplished with the results from stress analysis, removing unnecessary present dual calculation practice.

A Study on the Enhancement of Accuracy of Network Analysis Applications in Energy Management Systems (계통운영시스템 계통해석 프로그램 정확도 향상에 관한 연구)

  • Cho, Yoon-Sung
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.29 no.12
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    • pp.88-96
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    • 2015
  • This paper describes a new method for enhancing the accuracy of network analysis applications in energy management systems. Topology processing, state estimation, power flow analysis, and contingency analysis play a key factor in the stable and reliable operation of power systems. In this respect, the aim of topology processing is to provide the electrical buses and the electrical islands with the actual state of the power system as input data. The results of topology processing is used to input of other applications. New method, which includes the topology error analysis based on inconsistency check, coherency check, bus mismatch check, and outaged device check is proposed to enhance the accuracy of network analysis. The proposed methodology is conducted by energy management systems and the Korean power systems have been utilized for the test systems.

Optimize Design for 5MW Offshore Wind Turbine Sub-structure Jack-up Platform (5MW급 해상풍력 Sub-structure Jack-up Platform 최적화 설계)

  • Jeon, Jung-Do;Jeon, Eon-Chan
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.11 no.6
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    • pp.115-122
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    • 2012
  • The purpose of this study is to optimize the design of the jack-up platform for 5MW offshore wind turbine system. Considering all the environmental loads such as currents, waves, winds and so on, the members of structures have been designed and optimized based on the AISC and API-RP-2A to be within the allowable stress even in the most critical and severe condition. In addition to the above strength check of structural members, the joint punching shear check and the hydrostatic collapse check are also performed where they are required for the design. The design life of the jack-up platform is 50 years for the static strength check and the fatigue design life is 100 years including to the DFF(Design Fatigue Factor) of 2.0 to have enough stability and workability for the design optimization.

CopyCheck: Korean Document Plagiarism Detection System (CopyCheck: 한글문서 표절검사 소프트웨어)

  • Park, So-Yeong;Jang, Eun-Seo;Kwon, Do-Hyung;Kang, Seung-Shik
    • Annual Conference on Human and Language Technology
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    • 2013.10a
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    • pp.129-132
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    • 2013
  • 본 논문에서는 대학의 과제물이나 학위 논문 또는 회사의 입사지원서, 자기소개서와 같은 문서에 대하여 표절검사에 활용할 수 있는 소프트웨어인 CopyCheck를 설계 및 개발하였다. CopyCheck는 표절검사 방법을 빠른 검사와 정밀 검사를 두어 보다 사용자가 편리하게 사용할 수 있도록 하였다. 표절검사를 진행한 후, 전체보기와 구간보기, 표절구간 시각화의 3가지 방법을 통해 사용자가 다양한 방법으로 표절 문서를 파악할 수 있도록 도와준다. 또한, 표절검사 결과를 저장할 수 있도록 하여 사용자가 언제든지 다시 볼 수 있도록 하였다.

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An Analytical Investigation on Fluid Dynamics of Filler Neck Check Valve for On-board Refueling Vapor Recovery (주유중 증발가스제어 필러넥 체크밸브의 유동해석)

  • 김성훈;이재천
    • Journal of the Korean Society for Precision Engineering
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    • v.20 no.10
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    • pp.105-111
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    • 2003
  • ORVR filler neck check valve, which is one of the essential components of the vapor fuel control system, should diminish the evaporation by maintaining laminar fluid flow on refueling process. This study presents numerical. results of pressure and velocity distributions of the fluid flow in a ORVR filler neck check valve on refueling process. CFD-ACE+ has been employed for numerical analysis based on the information of experimental results of valve position as a function of inlet flow rate. No abrupt pressure change, which may causes vaporization of fuel, has been confirmed to take place on the concave surface of the valve spool. However, it is clear that some possibility exist at the mid-position of surface of valve spool and downstream according to the opening of valve.

Investigation on the Degradation Mechanism of 6" Swing Check Valve for Nuclear Power Plant (발전소 6 인치 역지밸브 손상 원인 분석)

  • Lee, Seon-Gi;Lee, Jun-Sin;Kim, Tae-Ryong
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.11a
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    • pp.138-144
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    • 2000
  • Degradation occurred at the 6 inch swing check valve in nuclear power plant. Valve replacement and maintenance were carried out during the plant O/H. This report examined the degradation mechanism of the 6 inch check valve by the experimental and theoretical study. Results shows that the degradation was caused by valve chattering which due to the structural and acoustic resonance.

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Selection-based Low-cost Check Node Operation for Extended Min-Sum Algorithm

  • Park, Kyeongbin;Chung, Ki-Seok
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.2
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    • pp.485-499
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    • 2021
  • Although non-binary low-density parity-check (NB-LDPC) codes have better error-correction capability than that of binary LDPC codes, their decoding complexity is significantly higher. Therefore, it is crucial to reduce the decoding complexity of NB-LDPC while maintaining their error-correction capability to adopt them for various applications. The extended min-sum (EMS) algorithm is widely used for decoding NB-LDPC codes, and it reduces the complexity of check node (CN) operations via message truncation. Herein, we propose a low-cost CN processing method to reduce the complexity of CN operations, which take most of the decoding time. Unlike existing studies on low complexity CN operations, the proposed method employs quick selection algorithm, thereby reducing the hardware complexity and CN operation time. The experimental results show that the proposed selection-based CN operation is more than three times faster and achieves better error-correction performance than the conventional EMS algorithm.

Modifications of heterobeltiosis, heterosis, and hybrid vigour over check parent formulae to enhance judgment on hybrids

  • Ghazy, Usama M.;Fouad, Tahia A.
    • International Journal of Industrial Entomology and Biomaterials
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    • v.42 no.2
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    • pp.33-45
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    • 2021
  • Many researchers are using the heterosis, heterobeltiosis and hybrid vigour over check parent value formulae to determine the hybrid vigour for animals, plants and silkworm breeding. These formulae are ideal for determine the hybrid vigour for the positive direction of single trait. It is difficult using these formulae for multiple traits. Suggested modification for cardinal formulae were made as well as suggestion new formula for determines hybrid vigour for multiple traits. Modifications of hybrid vigour were made to facilitate judgment of best hybrids under study for multiple traits. Nineteen local hybrids of mulberry silkworm were prepared for these investigations in addition the imported Bulgarian hybrid. Comparison between the cardinal and the modifications formulae were applied for thirteen economic characters. Nine positive and four negative direction characters were observed. Modified formulae make the judgment of heterobeltiosis, heterosis and hybrid vigour over check parent value very facilitate for positive and negative traits.

Refunds Reusable Electronic Check Payment System Using an EC-KCDSA Partially Blind Signature (EC-KCDSA 부분 은닉서명을 이용한 거스름 재사용 가능한 전자수표지불 시스템)

  • 이상곤;윤태은
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.13 no.1
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    • pp.3-10
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    • 2003
  • In this paper, a partially blind signature schemes baled on EC-KCDSA is proposed and we applied it to design an electronic check payment system. Because the proposed partially blind signature scheme uses elliptic curve cryptosystem, it has better performance than any existing schems using RSA cryptosystem. When issuing a refund check, one-time pad secret key is used between the bank and the customer to set up secure channel. So the symmetric key management is not required.

Suggestion of Safety Management Activities and Key Check point for Safety Management in Modular Construction Sites (모듈러 건설현장의 단위작업별 안전관리 활동 및 중점 체크사항 제안)

  • Jun, Young-Hun;Kim, Kyoon-Tai
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2022.04a
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    • pp.202-203
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    • 2022
  • In this study, focusing on work types of lifting modules and modules assembly in modular construction sites, unit works were defined according to the construction process of each work type, and safety management elements, safety management activities, and key check point were proposed. The results of this study may have somewhat overlapping contents in the construction procedure in order to derive specific safety management activities and check point for each unit work. Therefore, there is a limit to use the results in an actual modular construction site. In future research, we plan to improve this part and derive a checklist that considers field usability.

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