• Title/Summary/Keyword: Rolling Wave

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Operation of ULCS - real life

  • Prpic-Orsic, Jasna;Parunov, Josko;Sikic, Igor
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.6 no.4
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    • pp.1014-1023
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    • 2014
  • In this paper the real life operation of ULCS (Ultra Large Container Ships) is presented from the point of view of shipmasters. The paper provides interpretation of results of questionnaire filled by masters of large container ships during Tools for Ultra Large Container Ships (TULC) EUI FP7 project. This is done in a way that results of questionnaire are further reviewed and commented by experienced master of ULCS. Following phenomena are subject of questionnaire and further discussed in the paper: parametric rolling, slamming, whipping, springing, green water and rogue waves. Special attention is given to the definition of rough sea states as well as to measures that ship masters take to avoid them as well as to the manoeuvring in heavy seas. The role of the wave forecast and weather routing software is also discussed.

Flatness Control System of the Hot Strip by Using Tension Profile between Stands (스탠드간 장력프로파일을 이용한 열연판 평탄도 제어시스템)

  • 홍완기;이준정
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1999.08a
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    • pp.27-36
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    • 1999
  • To have high flatness quality of hot rolled strip in the hot strip finishing mill train, a new inter-stand tension profile measuring device of segmented looper roll type(coined as Flatness Sensing Inter-stand Looper, FlatSIL) and a new flatness control system have been developed in this study. The device measures the strip tension profile across the strip width and informs the strip wave pattern to new flatness control system where work roll bending mode to relieve the strip wave is determined. The existing automatic shape control system which uses laser type shape-meter installed at the outlet of the last finishing mill stand strip tension between down coiler and last finishig mill since the latent wave concealed by the strip tension between down coiler and last finishing mill stand cannot be measured by the laser distance-meter. Thus the existing shape control system is not able to control the flatness through the full strip length. The new flatness control system, however, works for full strip length during strip rolling as far as the tension profile measuring device and work roll bender are on. With the new flatness control system, work roll bender is automatically controller to minimize the latent wave of the running strip and the flatness quality as well as strip travelling stability has been noticeably improved from strip head through body to tail.

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An Artificial Immune system using Memory Cell for the Inventory Routing Problem (기억 세포를 이용한 재고-차량 경로 문제의 인공면역시스템)

  • Yang, Byoung-Hak
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2008.10a
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    • pp.236-246
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    • 2008
  • We consider the Inventory Routing problem(IRP) for the vending machine operating system. An artificial immune system(AIS) is introduced to solve the IRP. The IPR is an rolling wave planning. The previous solution of IRP is one of good initial solution of current IRP. We introduce an Artificial Immune system with memory cell (AISM) which store previous solution in memory cell and use an initial solution for current problem. Experiment results shows that AISM reduced calculations time in relatively less demand uncertainty.

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Estimation of Dynamic Conditions of Rolling Stock Structural Methods and Interpretations

  • Olegovich, Moskovskikh Alexander;Yur'evich, Upyr' Roman;Alekseevich, Zasjadko Anatolij
    • International Journal of Railway
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    • v.1 no.1
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    • pp.20-29
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    • 2008
  • Features of procedures of dynamic synthesis are considered at use of various interpretations or models of processes in mechanical oscillatory systems. Methodological bases for research of the wave processes develop, allowing receiving some features of distribution of indignations. Authors offer scientifically-methodical bases for the decisions received analytical by.

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A study on the development of motor-driven artificial heart and its control (인공심장의 자동제어)

  • 민병구;김희찬;권성일
    • 제어로봇시스템학회:학술대회논문집
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    • 1986.10a
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    • pp.643-647
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    • 1986
  • A new type of motor-driven Total Artificial Heart (TAH) system with rolling-ball mechanism has been developed. To test its performance as a Left Ventricular Assist Device (LVAD), LVAD is controlled to bypass blood for impaired heart triggered by the R-wave in ECG. Results of the test with a Mock Circulation System (MCS) and an animal experiment with a dog are also included. More powerful system using a brushless DC motor has been developed and its control scheme is represented.

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ESTIMATION OF DYNAMIC CONDITIONS OF ROLLING STOCK. STRUCTURAL METHODS AND INTERPRETATIONS.

  • Olegovich, Moskovskikh Alexander;Yur'evich, Upyp' Roman;Alekseevich, Zasjadko Anatolij
    • Proceedings of the KSR Conference
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    • 2007.11a
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    • pp.1920-1939
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    • 2007
  • Features of procedures of dynamic synthesis are considered at use of various interpretations or models of processes in mechanical oscillatory systems. Methodological bases for research of the wave processes develop, allowing receiving some features of distribution of indignations. Authors offer scientifically-methodical bases for the decisions received analytical by.

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A Study on the Scheduling of PETRONAS TWIN TOWER 2 PROJECT (PETRONAS TWIN TOWER 2 프로젝트의 공정관리에 관한 고찰)

  • 최순묵
    • Journal of the Korean Professional Engineers Association
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    • v.33 no.3
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    • pp.59-63
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    • 2000
  • The purpose of this study is to understand the method of scheduling of Petronas twin tower project. Petronas twin tower is the highest building in the world today. Kuala Lumpur City Center Berhad which is owner of Petronas twin tower, managed this construction project by use of useful scheduling techniques, that is, milestone, NSC, NS, PDM, rolling wave, hammock. Now we consider this techniques and try to apply to our construction management.

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Theoretical Study on the Characteristics of Pressure Change of High Speed Train in Tunnels (터널통과시 고속 철도 압력 변동 특성에 관한 이론적 연구)

  • Nam, Seong-Won;Kwon, Hyeok-Bin
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.28 no.9
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    • pp.1042-1050
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    • 2004
  • Theoretical study has been conducted to clarify pressure characteristics of KTX(Korea Train eXpress) in tunnel. The severe pressure change in tunnel may give rise to the ear-discomfort for passenger and fatigue for car body. The external and internal pressure of rolling stock have been measured by using the running test with atmospheric pressure sensors and portable data acquisition system in high speed train. In this study, the tunnels from 200m to 4000m in length have been chosen for the investigation of tunnel length effects. We found that there are similar patterns of external pressure change for each critical tunnel length. The critical tunnel lengths are governed by train speed, train length and sonic velocity. And, the patterns of pressure wave in tunnel are classified into eight groups.

Evaluation of Navigational Safety Using the Integrated Seakeeping Performance Index under Loading Conditions of a Ship (선박의 적화 상태별 종합내항성능지표에 의한 항해 안전성 평가)

  • 김순갑;김정만;공길영
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.4 no.2
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    • pp.43-52
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    • 1998
  • Generally, the navigational safety of a ship under various loading conditions is evaluated by a loading manual. However, the loading manual handles only statical factors such as weight and buoyancy of ship without including any wave conditions. Practically ship's safety is much concerned with the occurrences on the rough sea as propeller racing, rolling, deck wetness, vertical acceleration, lateral acceleration, slamming and so on. The purpose of this paper is to present a synthetic and practical evaluation method of navigational safety using the integrated seakeeping performance index(ISPI) under loading conditions of ship in seaways. The method is calculated by means of the ISPI by measuring only vertical acceleration. Judgement of dangerousness is carried out for four lading conditions : homogeneous full loaded, half loaded, heavy ballast loaded, and normal ballast loaded conditions. In developing the practical evaluation system of navigational safety, it is useful to solve the difficulties in measuring factors by sensors. And by applying the evaluation diagrames, navigators are able to avoid dangerousness by keeping away of the danger encountering angle of wave direction which the diagram shows.

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A Study on the Effect of Roughness of Rolling Roll in the Paintabilility of Strip (압연롤의 조도가 박판의 도장성에 미치는 영향에 관한 연구)

  • 김순경
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.7
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    • pp.36-43
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    • 1998
  • Surface roughness of cold rolled steel sheet as well as the coating technique itself is quite important in obtaining high image clarity of electronic products and car outer panels. Especially, surface characteristics of steel sheet have acquired increasing attention from the steel and automotive industries. While the influence of such characteristics on paintability formability and painted surface appearance is important in defining steel surface requirements for automotive industries. Therefore this paper is dedicated primarily to the issue of paint appearance and reviews for improvement of roughness and peak count about the surface of work roll for the actual temper mill. The conclusions were obtained as follows ; 1) Roughness and peak count about the surface of steel sheet is strongly affected by surface condition of work roll. 2) The electro-discharge textured roll has more uniform roughness distribution than shot blasted roll and it's painted appearance of steel sheet has more improvement than that of the shot blasted because it has more harmonic wave roughness, and the higher peak count of surface roughness.

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