• Title/Summary/Keyword: Stability check

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A quantitative methodology for evaluating the ship stability using the index for marine ship intact stability assessment model

  • IM, Nam-Kyun;CHOE, Hun
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.13 no.1
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    • pp.246-259
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    • 2021
  • IMO stability regulations include various stability parameters such as GM values. To assess the stability of the ships, we should check all stability parameters of the IMO requirements. However, since this process is complex, a more convenient way to evaluate stability performance is required. In this research, the index for marine ship intact stability assessment (IMSISA) model was developed to solve these problems. The IMSISA model consists of a stability index calculation module and a stability assessment module. In the stability index calculation module, ten stability parameters, including GM, were used to develop the stability index, which has the advantage of being able to quantify the ship stability. The stability assessment module uses the stability index value to determine the stability status of the ship and provides the captain with stability management guidelines. To verify the proposed model, the basic stability calculations were performed for two model ships in 32 loading situations. The proposed model was found to provide better performance in the stability assessment than the previous study. By applying the IMSISA model to the ships, the captain can assess the ship stability more quantitatively and efficiently.

Error Correcting using the Check digit on Barcode, and the present and future of Barcode (바코드에 있어서 체크숫자를 이용한 오류수정과 바코드의 현재와 미래)

  • Kim, Hwa-Joon
    • Journal for History of Mathematics
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    • v.21 no.2
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    • pp.103-118
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    • 2008
  • Barcode technology is becoming an essential tool for every companies, and this makes help us to gain time, analysis of goods, an inventory control, a prevention of burglar and so on. In this paper, we have treated about the history of barcode, its error correcting using the check digit, and the present and future of barcode. We wish roles of mathematician on new barcode system which it bring on an economical efficiency and stability.

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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.

Decentralized Dynamic Surface Control for Large-Scale Interconnected Systems (연결식 대형시스템을 위한 분산 동적 표면 제어)

  • Song Bong-Sob
    • Journal of Institute of Control, Robotics and Systems
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    • v.12 no.4
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    • pp.339-345
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    • 2006
  • An analysis methodology of Decentralized Dynamic Surface Control (DDSC) for the large-scale interconnected nonlinear systems is presented in this paper. While the centralized DSC approach proposed in [14] has a difficulty to check the quadratic stability for the large-scale systems numerically due to dramatic increases of the order of overall augmented error dynamics, DDSC is relatively easy to check the quadratic stability since lower order error dynamics of individual subsystems are used. Then, a systematic procedure for designing DDSC will be developed. Furthermore, after a quadratic function containing a reachable set is defined, it will be calculated numerically to indicate the performance of DDSC in the framework of convex optimization. Finally an illustrative example will be given for showing the advantages of DDSC compared with other decentralized nonlinear control techniques.

Design of Asynchronous Nonvolatile Memory Module with Self-diagnosis and Clock Function (자기진단과 시계 기능을 갖는 비동기용 불휘발성 메모리 모듈의 설계)

  • Woohyeon Shin;Kang Won Lee;Oh Yang
    • Journal of the Semiconductor & Display Technology
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    • v.22 no.1
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    • pp.43-48
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    • 2023
  • This paper discusses the design of 32Mbyte asynchronous nonvolatile memory modules, which includes self-diagnosis and RTC (Real Time Clock) functions to enhance their data stability and reliability. Nonvolatile memory modules can maintain data even in a power-off state, thereby improving the stability and reliability of a system or device. However, due to the possibility of data error due to electrical or physical reasons, additional data loss prevention methods are required. To minimize data error in asynchronous nonvolatile memory modules, this paper proposes the use of voltage monitoring circuits, self-diagnosis, BBT (Bad Block Table), ECC (Error Correction Code), CRC (Cyclic Redundancy Check)32, and data check sum, data recording method using RTC. Prototypes have been produced to confirm correct operation and suggest the possibility of commercialization.

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A General Tool Surface Contact Search and its Application to 3-D Sheet Forming (일반적인 금형면에서의 접촉탐색과 3차원 박판성형에의 응용)

  • 서의권;심현보
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1997.03a
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    • pp.121-124
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    • 1997
  • In the present study, a general tool surface contac search ad check algorithm is proposed. A general tool surface is described by triangular FE mesh. To check a proposed algorithm, clover cup and L-shape cup deep drawing processes are calculated. The elastic-plastic FEM using SEAM (Shear Energy Augmented Membrane) element is adapted for numerical stability.

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Change master cast by hardening method to position of tray after impression taking (인상채득 후 경화시 트레이의 위치에 따른 주모형의 변화)

  • Lee, Jung Ae
    • Journal of Korean society of Dental Hygiene
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    • v.8 no.2
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    • pp.53-66
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    • 2008
  • There was to purpose of this study improves analyzing cause that prosthesis brings bite engaging that is inaccurate in patient's mouth, when supposed that all conducts that do in operatory and dental laboratory are perfect. Impression did check bite by alginate impression material and polymerization style silicon impression material that use usually in presence at a sickbed Irreversibility, hydrocolloid, alginate impression material washed in flowing water and poured anhydrite after wait about 8 minutes so that region that charge interest after impression check bite may become undoing. And hydrophile property addition polymerization style impression material poured anhydrite after blow 30 considering impression material dwell time and H2 gas occurrence time (5~15 minute) after have washed in flowing water. I got each 7 models, result that manufactures total 28 and measures by third dimension measuring instrument (Meteo, Korea) following sequence curing in tray holder and floor 1, By Alginate impression when is hardened in tray holder and when is hardened in the floor after do check bite, SPH 4, SPH5 all as there is synonymy appeared(P<0.05). By in case do not use average 0.1741 in case use tray holder in 0.0447 SPH5s in case do not use average 0.2838 pastas in case use tray holder in SPH4 0.0309, When did not use both SPH4 and SPH5 tray holder, when used tray holder, 1 appeared more greatly. 2. By amity sex addition polymerization style silicon impression when is hardened in tray holder after do check bite and when is hardened in the floor SPH 4, a11 of the SPH5s very big synonymy be(P>0.05). And in case use tray holder in 0.000657 pasta SPH5s in case do not use average 0.000129 pastas in case use tray holder in SPH4 average 0.000114 pastas, by in case do not use 0.000757, I appeared more greatly when used tray when did not use both SPH4 and SPH5 tray holder, but 1 appeared is not level to keep in mind(Table 8~9). 3 SPH4 was looked very big mindfulness in model that manufacture doing impression check bite by Alginate and model that do impression check bite by amity sex accessory penalty silicon without using tray holder(P< 0.001). I use tray holder and SPH4 did not appear synonymy in model that manufacture doing impression check bite by Alginate and model that do impression check bite by amity sex accessory penalty silicon(P>0.05). Study finding of above when see synthesis Alginate certainly tray holder use must and I could know that hardening method does not exert big influence on volume stability if remove impression sieve of excess because amity sex accessory penalty silicon passes over tray, Also, Alginate impression material previewed can get heading a conspiracy style that volume stability of accessory penalty silicon impression material degree is if use tray holder.

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Construction Monitoring of Geotextile Tube at Young-Jin Bay and Stability Analysis by Hydraulic Model Tests (영진만 지오텍스타일 튜브의 현장 시공계측 및 수리모형시험을 통한 안정성분석)

  • 신은철;오영인;이명호
    • Proceedings of the Korean Geotechical Society Conference
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    • 2002.03a
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    • pp.549-556
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    • 2002
  • Geotextile tubes hydraulically or mechanically filled with dredged materials have been applied in hydraulic and coastal engineering in recent years(shore protection structure, detached breakwater, groins and jetty). It can also be used to isolate contaminated material from harbor, detention basin dredging, and to use this unit as dikes for reclamation work. Recently, new preliminary design criteria supported by model and prototype tests, and some stability analysis calculations have been studied. The stability analysis of geotextile tube is composed geotechnical and hydrodynamic analysis. The stability check points are sliding failure, overturning, bearing capacity failure against the wave attack. In this paper presented the construction procedure and in-situ measurement(properties of filling material, effective height variation, stress variation at geotextile tube bottom) of geotextile tube at Young-Jin Bay and stability analysis by theoretical method and hydraulic model tests

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