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Optimization Design of a Riser-Drill String Coupling System Based on CAE Techniques

Shiyao Qin, Ruiming Wang, Deyi Fu, Gaowei Wang, Yuqiang Xu
2021 Mathematical Problems in Engineering  
In a riser-drill string coupling system, the drill string extends from platform to downhole, and its exterior tube is divided by mud line into two parts: riser for upside and borehole for downside.  ...  By this way, the optimization design of the riser-drill string coupling system based on dynamic analysis can be conducted effectively and efficiently.  ...  [15] discussed the vibration suppression of a variable-length drilling riser system. e precise dynamic analysis of the riser-drill string coupling system is the precondition of its corresponding optimization  ... 
doi:10.1155/2021/6659632 fatcat:u6gesedutrep7j7kmk6nogwpre

Optimized SMA Dampers in Vibration Control of Jacket-type Offshore Structures (Regular Waves)

Mohammad Reza Ghasemi, Naser Shabakhty, Mohammad Hadi Enferadi
2019 International Journal of coastal and offshore engineering  
Dynamic responses of multidegree of freedom system of jacket platform, with 90 m height and equipped with SMA dampers, is estimated and compared with the bare jacket.  ...  The main objective of this research is to control wave-induced vibrations of fixed jacket platforms with the use of optimized shape memory alloys dampers.  ...  Design variables: 1) L 2) A Constraints: 1) ≥ 40 mm 2) ≤ Parameters L, A, and are the SMAs length, SMAs area, and austenite to martensite finish displacement, respectively.  ... 
doi:10.29252/ijcoe.2.4.25 fatcat:nioddou5srdungx4g2iwrsevba

英文版2009年第3期"机械科学专辑"摘要

2010 Scientia Sinica Technologica  
introducing a radial constraint of the well-bore.  ...  Understanding of the buckling behavior of a drill-string in a well-bore is crucial for the success of a drilling operation.  ...  Do and Pan [6] developed a nonlinear controller for an active heave compensation system, which may reduce heave motion of a vessel connected to the riser. Chen et al.  ... 
doi:10.1360/ze2010-40-3-320 fatcat:ewz7ocjff5h65ixvudgapxw43m

H∞ Iterative Learning Boundary Vibration Control of Uncertain Vibrating String with Iteration-Varying Distributed Disturbance and Boundary Disturbance

Ahmed Eshag, Ma, Sun, Zhang
2019 Applied Sciences  
Along the time, position, and iteration coordinates: (a) the boundary deflections of the string system are controlled; (b) the vibrations along the string are attenuated to zero; and (c) the external disturbances  ...  Firstly, MOL is employed to attain the string dynamics in the form of a state-space system instead of a PDE system.  ...  Introduction With the evolution of manufacturing, flexible structure-type systems are commonly used in a variety of engineering areas such as moving strips, adjustable marine risers, and drill cable strings  ... 
doi:10.3390/app9235122 fatcat:kt62skw6zre4fpkxa47bqrahhu

Methods [chapter]

2010 Proceedings of the Integrated Ocean Drilling Program  
Cuttings depths During riser drilling, drilling mud circulates within the riser pipe between the drillship and the bottom of the hole.  ...  The length of the drill string (combined length of the BHA and the drill pipe) and the position of the top drive in the derrick are used to determine the depth of the drill bit and ROP.  ...  MWD-APWD tool acronyms, descriptions, and units. (See  ... 
doi:10.2204/iodp.proc.319.102.2010 fatcat:o3uwbu3gtjc2jimxw5wk5fw2v4

Methods [chapter]

M. Strasser, B. Dugan, K. Kanagawa, G.F. Moore, S. Toczko, L. Maeda, Y. Kido, K.T. Moe, Y. Sanada, L. Esteban, O. Fabbri, J. Geersen (+29 others)
2014 Proceedings of the Integrated Ocean Drilling Program  
Due to damage incurred to the intermediate flex joint of the upper riser assembly during an emergency disconnect sequence after the passing of a cold weather front with associated high winds and rapid  ...  During riser operations, we expanded the data sets at Site C0002. Gas from drilling mud was analyzed in near real time in a mud-gas monitoring laboratory and was sampled for postcruise research.  ...  Cuttings and mud depths During riser drilling, drilling mud circulates within the riser pipe between the drillship and the bottom of the hole.  ... 
doi:10.2204/iodp.proc.338.102.2014 fatcat:nxtdumq47bbi5gkgzutfk5xeqq

Tau/Charm Factory Accelerator Report [article]

M.E. Biagini, R. Boni, M. Boscolo, A. Chiarucci, R. Cimino, A. Clozza, A. Drago, S. Guiducci, C. Ligi, G. Mazzitelli, R. Ricci, C. Sanelli, M. Serio (+27 others)
2013 arXiv   pre-print
The project aims at realizing a variable energy Flavor Factory between 1 and 4.6 GeV in the center of mass, and succeeds to the SuperB project from which it inherits most of the solutions proposed in this  ...  The present Report concerns the current status of the Italian Tau/Charm accelerator project and in particular discusses the issues related to the lattice design, to the accelerators systems and to the  ...  However, this assumption must be confirmed by a careful investigation on mechanical constraint between magnets and pumping system.  ... 
arXiv:1310.6944v1 fatcat:pakotudwqfae3eqganwrmd2mve

Reactor design for large scale suspension animal cell culture

J Varley, J Birch
1999 Cytotechnology (Dordrecht)  
In this review the importance of achieving a balance between mixing, mass transfer and shear effects is emphasised.  ...  However, due to the large difference in energy inputs used for microbial and animal cell systems such designs may be far from optimal.  ...  Acknowledgements Julie Varley would like to thank the Royal Academy of Engineering for facilitating her industrial secondment to LONZA Biologics.  ... 
doi:10.1023/a:1008008021481 pmid:19003342 pmcid:PMC3463394 fatcat:oitzvkzg2zehjoajtxnmjmhsri

Geotechnical Investigations [chapter]

2017 Horizontal Auger Boring Projects  
Purpose of the investigation, e.g., evaluate stability of existing structure, design a new structure. e. Complexity of site and structure. f. Topographic constraints. g. Difficulty of application. h.  ...  This type of investigation places special constraints on the methods which may be used. These constraints should be kept in mind by the designer. a. General.  ...  budget and time constraints.  ... 
doi:10.1061/9780784414583.ch04 fatcat:p2qq45y2bnhxzk7jykvxdmrpqe

Geotechnical Investigations [chapter]

Harvey W. Parker
1996 Tunnel Engineering Handbook  
Purpose of the investigation, e.g., evaluate stability of existing structure, design a new structure. e. Complexity of site and structure. f. Topographic constraints. g. Difficulty of application. h.  ...  This type of investigation places special constraints on the methods which may be used. These constraints should be kept in mind by the designer. a. General.  ...  budget and time constraints.  ... 
doi:10.1007/978-1-4613-0449-4_4 fatcat:6pyl4mwx7rhjphqoeqxoxfwugm

Shock and vibration computer programs: Reviews and summaries

W. Pilkey, B. Pilkey
1976 International Journal of Mechanical Sciences  
Thompson, and G. Homer at the University of Virginia. A very special word of thanks goes to C.  ...  This book contains critical reviews and summaries of available shock and vibration computer programs.  ...  ACKNOWLEDGEMENTS 1 and 2 .  ... 
doi:10.1016/0020-7403(76)90049-7 fatcat:kcqc5spzrzarnj6d3myaah3zda

Effects of errorless learning on the acquisition of velopharyngeal movement control

Andus Wing-Kuen Wong, Tara Whitehill, Estella Ma, Rich Masters
2012 Journal of the Acoustical Society of America  
A distinct peak in a room impulse response is usually associated with an acoustic path length of direct or reflected sound.  ...  The problem of estimating the directions-of-arrival (DOA) of a source in a room and its reflections using RIR data and microphone arrays, is considered.  ...  In the current paper, a method was proposed to estimate output power of HIFU using a hydrophone and infrared system.  ... 
doi:10.1121/1.4708235 fatcat:7wzupz5u2nd6nc7ttvbpxwvunm

Daniel R. Raichel: The Science and Applications of Acoustics

Nico Schuler
2001 Computer Music Journal  
The use in this publication of trade names, trademarks, service marks, and similar terms, even if they are not identified as such, is not to be taken as an expression of opinion as to whether or not they  ...  Use in connection with any form of information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed is forbidden.  ...  The riser system, essentially a floating floor with rigid interconnections and resilient materials just below the floor surface, acts to maximize cross stage vibrations.  ... 
doi:10.1162/comj.2001.25.4.92 fatcat:o3u27vcdpbbdtaqanqrerx2tii

The Long Baseline Neutrino Experiment (LBNE) Water Cherenkov Detector (WCD) Conceptual Design Report (CDR) [article]

The LBNE Collaboration
2012 arXiv   pre-print
Conceptual Design Report developed for the Water Cherenkov Detector (WCD) option for the far detector of the Long Baseline Neutrino Experiment.  ...  This system will require a stable (low-vibration) environment, and if vertically oriented, a high-bay space of ∼9 m.  ...  The production system will apply appropriate algorithms to each stream to maximize both the physics output and the convenience for analyzers, within the constraints of the available resources.  ... 
arXiv:1204.2295v1 fatcat:yuki457rivef5li4h2d3n3dyey

Spherical near field acoustic holography with microphones on a rigid sphere

Finn Jacobsen, Jo/rgen Hald, Efrén Fernandez, Guillermo Moreno
2008 Journal of the Acoustical Society of America  
There is a strong correlation between the subjective impression of reverberance with EDT and T30 and musical clarity with C80; 2.  ...  The results of the audience and expert scores were then statistically analyzed and correlated with a set of room acoustic indices which had been measured in the same locations.  ...  riser.  ... 
doi:10.1121/1.2934035 fatcat:57w2rziyfvcmnnyzsxlgg43qxa
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