• 제목/요약/키워드: Technology stability

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소형 어선 및 화물선의 복원성기준 연구 (Study on the Stability Criteria for Small Fishing Vessels and Cargo Ships)

  • 권수연;이희준
    • 선박안전
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    • 통권22호
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    • pp.19-33
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    • 2007
  • According to amendments of ship safety act which comes into force from 4 Nov. 2007, the amended stability criteria should be applied to the small vessels of 12m or more in length. In this paper, the dimensions of domestic small vessels and the casualty reports of capsizing accidents are analyzed. And 58 ships are sampled, modeled for the investigation of the stability performance. Based on the regression analysis of the model ship's allowable metacentric-heights under several stability requirements, stability criteria for small fishing vessels and cargo ships are proposed.

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Relaxing of the Sampling Time Requirement in Prove of the EDMC Stability

  • Haeri, Mohammad;Beik, Hossein Zadehmorshed
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2004년도 ICCAS
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    • pp.1829-1832
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    • 2004
  • Closed loop stability of Extended Dynamic Matrix Control (EDMC) is investigated for limited sampling time. Linear approximation of the sensitivity functions is employed in the derivation of the stability condition. It is shown that the closed loop system will be stable if the control moves suppression coefficient ${\lambda}$ is taken arbitrarily large. Special cases such as M=P=1 and M=1, P>1 are discussed in more details.

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재질 변화에 따른 초정밀가공기용 마이크로 스테이지의 안정성 해석 (Stability Analysis According to Material Alteration on Micro Stage for Micro Cutting Machine)

  • 김재열;곽이구;김항우
    • 한국공작기계학회논문집
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    • 제12권3호
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    • pp.52-57
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    • 2003
  • In this paper, stability of ultra precision cutting unit is analyzed and this unit is the kernel unit in ultra precision processing machine. According to alteration of shape and material about hinge, stability investigation is performed Through this stability investigation, trial and error is reduced in design and manufacture, at the same time, we are accumulated foundation data for unit control.

STABILITY OF RICCI FLOWS BASED ON KILLING CONDITIONS

  • Zhao, Peibiao;Cai, Qihui
    • 대한수학회지
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    • 제46권6호
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    • pp.1193-1206
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    • 2009
  • C. Guenther studied the stability of DeTurck flows by using maximal regularity theory and center manifolds, but these arguments can not solve the stability of Ricci flows because the Ricci flow equation is not strictly parabolic. Recognizing this deficiency, the present paper considers and obtains the stability of Ricci flows, and of quasi-Ricci flows in view of some Killing conditions.

Stability analysis to generally structured robust control problems

  • Cho, K.H.;Lim, J.T.
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1994년도 Proceedings of the Korea Automatic Control Conference, 9th (KACC) ; Taejeon, Korea; 17-20 Oct. 1994
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    • pp.369-372
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    • 1994
  • In this paper, the robust stability of characteristic polynomials with respect to real parameter variations is investigated through a new functional approach. Specifically there is no restriction on the interrelationship between coefficients of the polynomials. This allows one to treat the robust stability problems alike without distinction as to continuous or discrete time systems. Necessary condition and sufficient condition for the robust stability are shown and some examples extracted from two-link planar manipulator are provided.

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리어뷰 미러의 실차 동특성 및 주행시 동적 안정성(회전각)에 대한 평가 (On the Evaluation of In-Vehicle Dynamic Characteristics and On-Road Dynamic Stability(Angle of Rotation) of Rearview Mirror)

  • 정승균;이근수;김증한
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2008년도 추계학술대회논문집
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    • pp.385-386
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    • 2008
  • Dynamic stability of the vehicle rearview mirror is an important factor for the driver's visual perception (image blur) when driving down the road and regarded as one of the vehicle level N&V performance of visible component vibration. Several projects within GM identified a set of objective metrics and validation methods that can replace current existing subjective evaluation of mirror stability. This paper presents objective evaluation results for assessing dynamic stability (angle of rotation) of the vehicle rearview mirrors using both in-lab FRF measurements and on-road testing.

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Behaviour and stability of prestressed steel plate girder for torsional buckling

  • Gupta, L.M.;Ronghe, G.N.;Naghate, M.K.
    • Steel and Composite Structures
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    • 제3권1호
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    • pp.65-73
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    • 2003
  • A higher level of engineering standard in the field of construction, is the use of prestressing in building structures. The concept of prestressing steel structures has only recently been widely considered, despite a long and successful history of prestressing concrete members. Several analytical studies of prestressed steel girders were reported in literatures, but much of the work was not studied with reference to the optimal design and behaviour of the prestressed steel plate girder. A plate girder prestressed eccentrically, will behave as a beam-column, which is subjected to axial compression and bending moment which will cause the beam to buckle out. The study of buckling of the prestressed steel plate girder is necessary for stability criteria. This paper deals with the stability of prestressed steel plate girder using concept of "Vlasov's Circle of Stability" under eccentric prestressing force.

스핀코터를 이용한 박막의 기계적 안정성 평가 (Mechanical Stability Evaluation of Thin Film with Spin-coater)

  • 김지은;김정환;홍성철;조한구;안진호
    • 반도체디스플레이기술학회지
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    • 제15권1호
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    • pp.6-11
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    • 2016
  • For high volume manufacturing using extreme ultraviolet (EUV) lithography, mask protection from contamination during lithography process must be solved, and EUV pellicle is the strongest solution. Based on the technical requirements of EUV pellicle, EUV pellicle should have large membrane area ($110{\times}140mm^2$) with film transmittance over 90% and mechanical stability. Even though pellicle that satisfies size standard with high transmittance has been reported, its mechanical stability has not been confirmed, nor is there a standard to evaluate the mechanical stability. In this study, we suggest a rather simple method evaluating mechanical stability of pellicle membrane using spin-coater which can emulate the linear accelerated motion. The test conditions were designed by simulating the acceleration distribution inside pellicle membrane through correlating the linear acceleration and centripetal acceleration, which occurs during linear movement and rotation movement, respectively. By these simulation results, we confirmed the possibility of using spin-coater to evaluate the mechanical stability of EUV pellicle.

Nexus among Bank Competition, Efficiency and Financial Stability: A Comprehensive Study in Bangladesh

  • RAHMAN, Syed Mohammad Khaled;CHOWDHURY, Mohammad Ashraful Ferdous;TANIA, Tasmina Chowdhury
    • The Journal of Asian Finance, Economics and Business
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    • 제8권2호
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    • pp.317-328
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    • 2021
  • This study examines the impact of bank competition and efficiency in the financial stability of the banking sector in Bangladesh. The study used the Lerner index and the Boone indicator to represent the bank competition, while the non-performing loan (NPL) and Z-score are used to represent financial stability. The secondary data were collected from the annual reports of 28 DSE listed commercial banks of Bangladesh over the period from 2011 to 2018. Using a dynamic panel GMM model, the study found the Lerner index is significantly negatively related with Z-score, which means that higher bank competition results in higher bank stability. It is also seen that higher cost efficiency results in higher bank stability. The Lerner index has negative, but insignificant impact on NPL. Similarly, using the Boone indicator, this study found that lower competition increases NPL. In terms of the Z-score, the Boone indicator found that 1 unit of increment results in decrease of the Z-score by 6.15 units. The study suggests that, as more competition results in more financial soundness, the banking industry competition should be ensured by policymakers or regulators. Banks could enhance financial stability by cost control to achieve cost efficiency as well as by improving loan-to-asset ratio.

니켈 실리사이드의 열안정성에 대한 실리카 상부막과 코발트 중간막의 영향 (Effect of silica top layer and Co interlayer on the thermal stability of nickel silicide)

  • 한길진;조유정;김영철;오순영;김용진;이원재;이희덕
    • 반도체디스플레이기술학회지
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    • 제4권2호
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    • pp.7-10
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    • 2005
  • [ $SiO_{2}$ ] or SiON is usually deposited and annealed after formation of silicide in real transistor fabrication processes. Nickel silicide and nickel silicide with Co interlayer were annealed at 650$^{\circ}C$ for 30 min with silica top layer in this study to investigate its thermal stability. SEM, XPS, and FPP(four point probe) were employed for the investigation. Nickel silicide with Co interlayer showed improved thermal stability. Co interlayer seems to play a key role to the stability of nickel silicide.

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