• Title/Summary/Keyword: Go-bang

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탄약 비군사화 기술현황 분석-폐탄 및 불용탄 처리, 어떻게 할 것인가?

  • Lee, Jong-Cheol;Park, Bang-Sam;Go, Bok-Nam
    • Defense and Technology
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    • no.2 s.264
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    • pp.34-42
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    • 2001
  • 향후 우리 군은 작전소요 등 특별한 경우를 제외하고는 불용탄의 야외처리를 단계적으로 축소하지 않으면 안 될 것이며 이에 대한 환경감시는 더욱 강화될 것이다. 뿐만 아니라 NIMBY 현상 등 지역 이기주의에 따라 현재기술로 가장 안전하다고 입증된 소각 대체기술로서 환경과 폭발안전을 도모할 수 있는 새로운 기술이 요구되고 있다.

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Improving Joint Reliability of Lead-free Solder on Flexible Substrate under Cyclic Bending by Adding Graphene Oxide Powder (그래핀 산화 분말을 첨가한 플렉시블 기판 솔더 접합부의 반복 굽힘 신뢰성 향상)

  • Ko, Yong-Ho;Yu, Dong-Yurl;Son, Junhyuk;Bang, Junghwan;Kim, Taek-Soo
    • Journal of the Microelectronics and Packaging Society
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    • v.26 no.3
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    • pp.43-49
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    • 2019
  • In this study, a new approach using graphene oxide (GO) powder-composited Sn-3.0Ag-0.5Cu(in wt.%) solder paste for improving the bending reliability of solder joints between a flexible substrate and small outline package (SOP) was suggested. The GO addition slightly affected the melting temperature, however, the change in the melting temperature was not significant. Meanwhile, we observed the addition of GO could suppress IMC growth and IMC thickness of solder joint during the reflow process. Moreover, the cyclic bending test was also performed for evaluation of reliability in solder joint and we could improve the cyclic bending reliability of solder joint by adding GO powders. For 0.2 wt.% of GO added to the solder joint, the bending lifetime was increased to 20% greater than that without GO. Pull strength and ductility of the solder joint with GO were also higher than those of the joint without GO and it was assumed that this effect by adding GO could contribute to improve cyclic bending reliability of solder joint.

Guidance Law for Vision-Based Automatic Landing of UAV

  • Min, Byoung-Mun;Tahk, Min-Jea;Shim, Hyun-Chul David;Bang, Hyo-Choong
    • International Journal of Aeronautical and Space Sciences
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    • v.8 no.1
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    • pp.46-53
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    • 2007
  • In this paper, a guidance law for vision-based automatic landing of unmanned aerial vehicles (UAVs) is proposed. Automatic landing is a challenging but crucial capability for UAVs to achieve a fully autonomous flight. In an autonomous landing maneuver of UAVs, the decision of where to landing and the generation of guidance command to achieve a successful landing are very significant problem. This paper is focused on the design of guidance law applicable to automatic landing problem of fixed-wing UAV and rotary-wing UAV, simultaneously. The proposed guidance law generates acceleration command as a control input which derived from a specified time-to-go ($t_go$) polynomial function. The coefficient of $t_go$-polynomial function are determined to satisfy some terminal constraints. Nonlinear simulation results using a fixed-wing and rotary-wing UAV models are presented.

The Impact of the ERP Go-Live Issues on User Satisfaction (ERP 프로젝트에서 사용자만족도에 영향을 미치는 가동(Go-Live)시점 활동특성)

  • Chun, Hong-Mal;Bang, Myung-Ha
    • Information Systems Review
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    • v.9 no.1
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    • pp.139-160
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    • 2007
  • Our study focuses on empirical findings of the critical factors which influence the performance of ERP system in business. The study is mainly interested in examining the influence of the characteristics of late process of adopting ERP called "Go-Live" phase with the critical issues like customizing, transformational process of standardization, phased implementation, concurrent operation and use with the current systems on users' ERP satisfaction. The analyses of the data conducted thru moderated regression analysis and subgroup analysis. Using moderated regression analysis, we first examined the effect of moderator variables like customizing, process standardization, sequential use, concurrent use with the current systems. And then, using subgroup analysis is to verify directions of the moderator effects. Having knowledge on the characteristics of ERP Go-Live process can lead to success of ERP system in business. Our results can be beneficial to those organizations who want to adopt and maintain ERP system effectively.