• Title/Summary/Keyword: Performance Trend

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Investigation on the Recent Research Trend in the Corrosion Behaviour of Stainless Steel Weldment

  • Kim, Hwan Tae;Kil, Sang Cheol;Hwang, Woon Suk
    • Corrosion Science and Technology
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    • v.10 no.3
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    • pp.77-79
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    • 2011
  • The research trend in the corrosion behaviour of stainless steel weldment has been reviewed. The welding technology plays an important role in the fabrication of structure such as chemical plant, power plant, because welding can influence various factors in the performance of plant and equipment. This has led to an increasing attention towards the corrosion behaviour of weldment which has been one of the major issues for both welding and corrosion research engineers. The aim of this paper is to give a short survey of the recent technical trends of welding and corrosion including the electrochemical corrosion, stress corrosion cracking, and corrosion fatigue in connection with the welding materials, welding process, and welding fabrication. This study covers the corrosion behaviour of stainless steel weldment collected from the COMPENDEX DB analysis of published papers, research subject and research institutes.

Recent Trend of International Standards on the Safety Criteria for Electric Shock Protection (인체감전 안전기준에 관한 최근 국제규격의 동향)

  • Lee, Jong-Chul;Kim, Han-Soo;Lee, Ju-Chul;Kang, Sung-Man
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2007.11a
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    • pp.189-193
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    • 2007
  • The grounding of an electrical system is one of the essential elements for public safety. Domestic practice of grounding system design has been to get grounding resistance values which are classified by facilities or equipment in the regulations. But the concept of grounding system design of IEC is, as a main factor of safety index, to consider touch voltage and step voltage instead of the resistance value itself. Recently IEC actively develops or revises safety related standards which are essential for the grounding system performance. In this paper, we present the recent trend of the international standards on the safety criteria for Electric Shock Protection.

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A Study of Helicopter Initial Sizing using Statistical Methodology (통계적 기법을 적용한 헬기 형상설계 연구)

  • Kim, June-Mo;Oh, Woo-Seop
    • Journal of the Korea Institute of Military Science and Technology
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    • v.10 no.1
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    • pp.22-32
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    • 2007
  • This paper describes a study of a helicopter database for the sizing stage of a preliminary design process. The database includes specifications and performance parameters for more than 150 conventional single rotor helicopters currently in market. Design parameters, including configuration and weight parameters, have been analyzed and trend curve equations(regression equations) are derived using the regression analysis method. Finally, the applicability of this research result was verified whether the method is reliable for being adopted as a useful design tool in the early stage of a helicopter design process.

Development Trend of Light Sport Aircraft and Certification Policy (경량항공기 개발동향 및 인증제도 고찰)

  • Kim, Yong-Seok;Shin, Hong-Chul;Shin, Dai-Won
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.18 no.3
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    • pp.84-91
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    • 2010
  • New aircraft category such as Light Sport Aircraft is introduced to prevent Ultralight Vehicle accidents and to promote aviation sports. Therefore, a new rule for airworthiness standard, certification, operation and maintenance of light sport aircraft is being created. The present study deals with LSA concept, development trend of LSA, airworthiness standards and certification policy. In particular, an aircraft type analysis of FAA certified LSA is conducted to establish performance requirements of Light Sport Aircraft designs.

Research for Patent Application Tendency in the High Reliable Machining Center for Making of Ultra Precisional Component (고정밀 부품 가공을 위한 고유연성 머시닝센터의 특허동향 분석에 관한 연구)

  • Kim, Seung-Min;Ko, Jun-Bin;Park, Hee-Sang
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.17 no.6
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    • pp.1-7
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    • 2008
  • This paper research the trend of technology of the high efficient and reliability machining center and high flexibility parallel manipulator machining center including linear motor machining center, submicron machining center and direct drive 5 axis machining center using patent information of Korea, U.S.A, Japan and Europe. By using this, the technique level of Korea, the International trend of technology and condition of cooperation research was estimated and the necessity of research and development performance about the machining center for the IT part processing were inquired.

Gamma-ray Detectors for Nuclear Medical Imaging Instruments (핵의학 영상기기의 감마선 검출기)

  • Cho, Gyu-Seong
    • Nuclear Medicine and Molecular Imaging
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    • v.42 no.2
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    • pp.88-97
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    • 2008
  • In this review paper, basic configurations of gamma detectors in SPECT and PET systems were reviewed together with key performance parameters of the imaging system, such as the detection efficiency, the spatial resolution, the contrast resolution, and the data acquisition time for quick understanding of the system-component relationship and future design of advanced systems. Also key elements of SPECT and PET detectors, such as collimators, gamma detectors were discussed in conjunction with their current and future trend. Especially development trend of new scintillation crystals, innovative silicon-based photo-sensors and futuristic room-temperature semiconductor detectors were reviewed for researchers who are interested in the development of future nuclear medical imaging instruments.

A study on a structural analysis of the injection mold for the plastic subminiature barrel (모바일용 플라스틱 경통 금형의 구조해석에 관한 연구)

  • Chang, Sung-Ho;Heo, Young-Moo;Shin, Gwang-Ho
    • Design & Manufacturing
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    • v.2 no.3
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    • pp.10-15
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    • 2008
  • Recently, mobile-phone with camera module has an absolute majority in the released mobile-phones. For this trend, High precision of the plastic subminiature barrel which is the core part is needed significantly because the camera module of mobile-phone must have high performance. Therefore, Structural stability of the injection mold for plastic subminiature barrel has to be guaranteed. In this paper, structural analysis of injection mold for plastic subminiature barrel is performed. Finally, the deformation trend and stability of injection mold core are analyzed.

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The performance and quality improvement of Lithium ion Batteries

  • Xiaoping Li
    • 한국전기화학회:학술대회논문집
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    • 2004.11a
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    • pp.75-108
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    • 2004
  • The market, development and trend of Lithium ion Batteries in China are introduce briefly. Early, Chinese manufactories were busy to expand and many new battery factories have been built up. Now, the relatively large companies pay more attentions on comprehensive quality improvement, therefore the production processing and facilities have been also modified in some extent. The recent technology progresses focus on High capacity (energy density), High rate, High average voltage, High safety, High temperature properties, Long cycle life, Low temperature properties, Low self discharge, Low cost, Super-large, Super-small, Super-thin, Consistency, Customization, and Environment friendly processing, simply $H_5L_4S_3C_2E_1$. Lithium ion polymer batteries which all batteries packaged with soft lamination film are named as in China have a quick growth and emphasized here because of their advantages ins $H_5L_4S_3C_2E_1$ for which it is quite difficult to be realized at the same time. Some of research works such as listed above are introduced. The other contends related to application trend of Lithium ion batteries and projects carrying out are also included.

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Improvement of Network Traffic Monitoring Performance by Extending SNMP Function

  • Youn Chun-Kyun
    • Proceedings of the IEEK Conference
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    • summer
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    • pp.171-175
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    • 2004
  • Network management for detail analysis can cause speed decline of application in case of lack band width by traffic increase of the explosive Internet. Because a manager requests MIB value for the desired objects to an agent by management policy, and then the agent responds to the manager. Such processes are repeated, so it can cause increase of network traffic. Specially, repetitious occurrence of sending-receiving information is very inefficient for a same object when a trend analysis of traffic is performed. In this paper, an efficient SNMP is proposed to add new PDUs into the existing SNMP in order to accept time function. Utilizing this PDU, it minimizes unnecessary sending-receiving message and collects information for trend management of network efficiently. This proposed SNMP is tested for compatibility with the existing SNMP and decreases amount of network traffic largely

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Technical Trend of Lens for Optical tracking system (광학추적장비용 렌즈의 기술 동향)

  • Park, Doo-Jin;Noh, Young-Hwan;Kim, Tae-Hyung;Lee, Hyo-Keun
    • Current Industrial and Technological Trends in Aerospace
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    • v.9 no.1
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    • pp.150-157
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    • 2011
  • In launch site, optical tracking system equipped with high performance lens is used to acquire images of launch vehicle in the early stage of the ascent phase. This article describes a technical trend of various lens as well as its application to optical tracking system.

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