The Effects of Boundary Conditions and Friction on the Helical Buckling of Coiled Tubing in an Inclined Wellbore. [PDF]
PLoS ONE, 2016 Analytical buckling models are important for down-hole operations to ensure the structural integrity of the drill string. A literature survey shows that most published analytical buckling models do not address the effects of inclination angle, boundary ...
Yinchun Gong +3 more
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Islands of conformational stability for filopodia. [PDF]
PLoS ONE, 2013 Filopodia are long, thin protrusions formed when bundles of fibers grow outwardly from a cell surface while remaining closed in a membrane tube.
D Robert Daniels, Matthew S Turner
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Analysis of sinusoidal post-buckling deformation of horizontal coiled tubing with initial residual bending. [PDF]
PLoS ONEIn the process of horizontal well construction, the working environment in the well is very complicated. It is difficult to determine the actual deformation and force of the coiled tubing in the wellbore from the load change at the wellhead along.
Zhuang Li +3 more
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Magnetically controlled microrobotic system for programmable stiffness tuning and active steering of microcatheters [PDF]
Nature CommunicationsSurgical tasks in small tortuous lumens demand interventional instruments with controllable mechanical adaptability. However, current microcatheters lack a non-disruptive, integration-ready strategy for dynamic stiffness tuning—critical for meeting the ...
Yuan Liu +7 more
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Analysis of Torsional Response in Pneumatic Artificial Muscles [PDF]
BiomimeticsPneumatic artificial muscles (PAMs) consist of an elastomeric bladder wrapped in a helical braid. When inflated, PAMs expand radially and contract axially, producing large axial forces.
Frank C. Cianciarulo +2 more
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The ancient and helical architecture of Elasmobranchii's spermatozoa enables progressive motility in viscous environments. [PDF]
PLoS ONESubclass Elasmobranchii belongs to an old evolutionary class of Chondrichthyes that diverged 450 mya, presenting a wide diversity of reproductive strategies while preserving the ancient mode of internal fertilization.
Sergii Boryshpolets +6 more
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Reversible actuation of fibrous artificial muscle under external compression load [PDF]
Scientific ReportsHerein, we report hybrid fibrous artificial muscles with reversible actuation, i.e., expansion upon cooling and contraction upon heating, under external compression.
Xiaming Feng +3 more
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Liner Pressure Test Buckling Generation and Influences on Running String and Cement Quality of Previous Casing in Vertical Wells [PDF]
Journal of Chemical and Petroleum Engineering, 2023 Buckling occurrence during liner pressure test represents a challenge, in addition to running string deformation; previous casing cement quality may be severely affected.
Leksir Abdeslem
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Minimal Mass and Maximal Buckling Load of Composite Hexagonal-Triangle Grid Structure using FSDT under External Hydrostatic Pressure [PDF]
Mechanics of Advanced Composite Structures, 2023 Grid-stiffened composite shells are one of the most important structures in many industries. These structures based on their fabrication method, provide both high strength and light structural weight.
Mahsa Soheil Shamaee, Ahmad Reza Ghasemi
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The Analytic Technique and Experimental Research Methods of Post-buckling about Slender Rod Strings in Wellbore [PDF]
Journal of Petroleum Science and Technology, 2016 The buckling behavior of rod strings in wellbore is one of the key issues in petroleum engineering. The slender rod strings in vertical wellbore were selected as research objects.
Yue Qian Bei, Liu Ju-bao, Fu Mao-qing
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