• Title/Summary/Keyword: Test procedures

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Study on Vibration Characteristic Improvement of Aircraft Landing Gear Handle (항공기용 착륙장치 핸들의 진동 특성 개선에 관한 연구)

  • Kang, Gu Heon;Ahn, Jong Moo
    • Journal of Aerospace System Engineering
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    • v.12 no.2
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    • pp.59-65
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    • 2018
  • The landing gear (L/G) handle of an aircraft is an essential piece of equipment for aircraft take-off and landing. The bracket in the landing gear handle was fractured during a vibration test when developing the landing gear handle. This paper summarizes the vibration test procedures performed during landing gear handle development. A cause analysis, design improvements, and verification results of the fault in the vibration test are also provided.

Diagnostic Evaluation Methods in TMJ Balancing Medicine (턱관절균형의학의 기본 진단검사법)

  • Lee, Young-Jun;Yin, Chang Shik
    • Journal of TMJ Balancing Medicine
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    • v.3 no.1
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    • pp.27-30
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    • 2013
  • Diagnostic evaluation methods frequently adopted in Temporomandibular Balancing Medicine (TBM) are briefly reviewed as to their basic concepts and procedures. TBM diagnostic evaluation methods may be classified into direct and indirect ones. Indirect methods are to observe any change in the manifestations with regard to the (1) posture, (2) pain, (3) muscle strength, and (4) stretching. Direct methods are to evaluate through (1) cervical palpation test, (2) restricted cervical rotation test, and (3) lateral cervical tension test. These methods may provide clinicians valuable information on the current yinyang balance and potential therapeutic factors in relation with the temporomandibular joint, a meridian system, and the whole body.

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A Comparison Study of the Test for Right Censored and Grouped Data

  • Park, Hyo-Il
    • Communications for Statistical Applications and Methods
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    • v.22 no.4
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    • pp.313-320
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    • 2015
  • In this research, we compare the efficiency of two test procedures proposed by Prentice and Gloeckler (1978) and Park and Hong (2009) for grouped data with possible right censored observations. Both test statistics were derived using the likelihood ratio principle, but under different semi-parametric models. We review the two statistics with asymptotic normality and consider obtaining empirical powers through a simulation study. The simulation study considers two types of models the location translation model and the scale model. We discuss some interesting features related to the grouped data and obtain null distribution functions with a re-sampling method. Finally we indicate topics for future research.

[ $SRV^{(R)}$ ]-Testing of the Tribosystem Piston Ring and Cylinder Liner Outside the Engine

  • Woydt Mathias;Ebrecht Johannes
    • KSTLE International Journal
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    • v.6 no.2
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    • pp.58-64
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    • 2005
  • An OEM driven working group started in January 2004 to elaborate the philosophies, concepts and test procedures for testing piston ring and cylinder liner materials as well as engine oils outside the engine using the $SRV^{(R)}$ test equipment. The different $SRV^{(R)}$ test philosophies in use by OEMs are compiled. The working group focuses on a.) ASTM sequence VIB (Fuel economy by aging oils), b.) friction and wear in the top dead region under mixed/boundary lubrication, c.) extreme pressure load under mixed/boundary lubrication and d.) hydrodynamic friction. Tribological test result and precision data are presented.

Identify Hypoid Gear Whine Noise for Deflection Test and Transmission Error Measurement (하이포이드 기어의 소음원인규명을 위한 디플렉션 테스트와 전달오차 측정에 대한 연구)

  • Choi, Byung-Jae;Oh, Jae-Eung;Park, Sang-Gil
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.19 no.2
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    • pp.127-137
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    • 2009
  • Hypoid gears are widely used in rear drive and 4WD vehicle axles. Investigation of their sensitivity to deflections is one of the most important aspects of their design and optimization procedures. The deflection test is performed in the actual gear mounting using completely processed gear. This test should cover the full operating range of gear loads from no load to peak load. Under peak load the contact pattern should extend to the tooth boundaries without showing a concentration of the contact pattern at any point on the tooth surface. Transmission error is tested on an axle assembly triaxial real car load condition.

A study on railway performance test management program building based on X-internet (X- 인터넷 기반의 철도성능시험관리 프로그램 구축에 관한 연구)

  • Ohn, Jung-Ghun;Kim, Myung-Ryoung;Yang, Doh-Chul
    • Proceedings of the KSR Conference
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    • 2008.11b
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    • pp.2096-2100
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    • 2008
  • This research project management, building systems to test the performance requirements of a user to accept the plan and schedule management, personnel management, and test results, and the status of testing and reporting procedures to handle the process of implementation of Java-based X - Under the Internet environment, the default network, remote process research and development program as a test automation, structure and each module of the software analysis, design, analysis and clean-up and structure of the modules, each module and the GUI structure, performance, testing integration DB The present system is to study the system.

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A study on the Tailoring of Environmental Requirements for XKT-1T Aircraft (XKT-1T 항공기 환경 요구사항 적합화 연구)

  • Kim, Jin Seog
    • Journal of the Korean Society of Systems Engineering
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    • v.17 no.1
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    • pp.97-106
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    • 2021
  • The purpose of the study on the tailoring of environmental requirements for KT-1 Export Version(XKT-1T) aircraft is not only based on meeting the compliance of the environmental reliability, customer satisfaction, but also for the expansion of its export. This paper proposes the environmental requirements tailoring processes and High/Low temperature conditions, test procedures, and the results of test profiles for the aircraft. Amongst many existing environmental requirements, the temperature requirements are considered as the most basic and the most important environmental requirements. The High/Low temperature tests are considered and tailored to the high and low temperature methods of MIL-STD-810.

A Study on Improvement Scheme for Korea's Motor Vehicle Safety Standards Implementation Rules System (자동차 안전기준 시행세칙 체계 정비방안 연구)

  • Kim, Gyuhyun
    • Journal of Auto-vehicle Safety Association
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    • v.14 no.3
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    • pp.77-82
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    • 2022
  • The Korea's automobile safety standards consist of standards for automobiles, automated vehicles, two-wheeled vehicles and auto parts, and there are 157 articles. In connection with the safety standards, the implementation rules stipulated for detailed test methods and procedures are composed of the main body, asterisks and annexes, and have a rather complicated structure. In addition, the test items in the asterisk are specified with the same or similar name as the test items in other asterisks. In this study, the structure of these implementation rules is simplified and the same test items are integrated. This is expected to increase the user's understanding of laws and regulations and efficiency.

Blockchain and Cryptocurrency Distributed Testing Methods

  • Lee, Taegyu
    • International Journal of Internet, Broadcasting and Communication
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    • v.14 no.1
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    • pp.1-9
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    • 2022
  • Recently, a large number of cryptocurrencies and block chains have been continuously released. However, these cryptocurrencies and block chains are open to users without authorized verification and testing procedures, causing various reliability problems. Existing cryptocurrencies and blockchain test methods build a blockchain Testnet for a certain period of time by the developer without external verification by a third party, and after repeatedly self-testing and self-operating processes, commercialization is in progress by switching to the Mainnet. This self-verification method does not guarantee objectivity and publicness, and high reliability of customers cannot be realized. This study proposes a cryptocurrency and blockchain test interface and test control system as a third-party open test method.

Investigation on the thermal butt fusion performance of the buried high density polyethylene piping in nuclear power plant

  • Kim, Jong-Sung;Oh, Young-Jin;Choi, Sun-Woong;Jang, Changheui
    • Nuclear Engineering and Technology
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    • v.51 no.4
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    • pp.1142-1153
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    • 2019
  • This paper presents the effect of fusion procedure on the fusion performance of the thermal butt fusion in the safety class III buried HDPE piping per various tests performed, including high speed tensile impact, free bend, blunt notched tensile, notched creep, and PENT tests. The suitability of fusion joints and qualification procedures was evaluated by comparing test results from the base material and buttfusion joints. From the notched tensile test result, it was found that the fused joints have much lower toughness than the base material. It was also identified that the notched tensile test is more desirable than the high speed tensile impact and free bend tests presented in the ASME Code Case N-755-3 as a fusion qualification test method. In addition, with regard to the single low-pressure fusion joint performances, the procedure given by the ISO 21307 was determined to be better that the one specified in the Code Case N-755-3.