Results 51 to 60 of about 62,218 (321)
Stability Analysis and Visual Application of Drill String Drag and Torque Test Device
Shiyou jixie, 2021 The nonlinear buckling of the drill string during drilling affects the safe and stable operation of the drag and torque test device. For the horizontal well drag and torque test device, based on the dynamic software ADAMS, combined with the force balance
Wu Zebing +5 more
doaj
Development of Heat Engines Powered by Twisted and Coiled Polymer Fiber Actuators
Advanced Materials Technologies, EarlyView.Continuously rotating engines driven by thermally responsive actuating materials can turn waste heat into useful energy. For the first time heat engines operated by twisted and coiled polymer fiber actuators are demonstrated with engine design guided by two simple analytical models.
Geoffrey M. Spinks +2 more
wiley +1 more source
Horseshoe drag in three-dimensional globally isothermal disks [PDF]
, 2016 We study the horseshoe dynamics of a low-mass planet in a three-dimensional, globally isothermal, inviscid disk. We find, as reported in previous work, that the boundaries of the horseshoe region (separatrix sheets) have cylindrical symmetry about the ...
Benítez Llambay, Pablo, Masset, F. S.
core +1 more source
Improved stiff string torque and drag prediction using a computationally efficient contact algorithm
Mathematical and Computer Modelling of Dynamical SystemsDue to the intermittent contact with the wellbore, determining torque and drag for deviated wells is difficult. Most models have ignored drill string stiffness and assumed continual contact to simplify derivation.
Sampath Liyanarachchi, Geoff Rideout
semanticscholar +1 more source
Stable Imitation of Multigait and Bipedal Motions for Quadrupedal Robots Over Uneven Terrains
Advanced Robotics Research, EarlyView.How are quadrupedal robots empowered to execute complex navigation tasks, including multigait and bipedal motions? Challenges in stability and real‐world adaptation persist, especially with uneven terrains and disturbances. This article presents an imitation learning framework that enhances adaptability and robustness by incorporating long short‐term ...
Erdong Xiao +3 more
wiley +1 more source
Multi-fidelity modelling of shark skin denticle flows: insights into drag generation mechanisms
Royal Society Open Science, 2023 We investigate the flow over smooth (non-ribletted) shark skin denticles in an open-channel flow using direct numerical simulation (DNS) and two Reynolds averaged Navier–Stokes (RANS) closures. Large peaks in pressure and viscous drag are observed at the
C. J. Lloyd +6 more
doaj +1 more source
Tuning the torque-speed characteristics of bacterial flagellar motor to enhance the swimming speed
, 2019 In a classic paper, Edward Purcell analysed the dynamics of flagellated bacterial swimmers and derived a geometrical relationship which optimizes the propulsion efficiency. Experimental measurements for wild-type bacterial species E.
Abdulla, Amith Z. +3 more
core +1 more source
Pendidikan teknik dan vokasional di kalangan masyarakat orang asli [PDF]
, 2007 Masyarakat Orang Asli adalah golongan unik yang mempunyai pelbagai fahaman dan cara hidup yang berbeza-beza berbanding masyarakat lain di Malaysia. Penguasaan di dalam bidang Pendidikan Teknik dan Vokasional (PTV) akan dapat membantu mereka untuk terus ...
Ahmad Sapawi, Arman
core +1 more source
Modulus‐Switchable Miniature Robots for Biomedical Applications: A Review
Advanced Robotics Research, EarlyView.Materials, robot designs, proof‐of‐concept functions, and biomedical applications of modulus‐switchable miniature robots. Miniature soft robots have shown great potential in biomedical applications due to their excellent controllability and suitable mechanical properties in biological environments.
Chunyun Wei, Yibin Wang, Jiangfan Yu
wiley +1 more source
Jixie chuandong, 2022 In order to study the influence of multiple clutches on the transmission efficiency of a hydro-mechanical continuously variable transmission （HMCVT），the structure characteristics of a closed loop consisting of multiple wet friction clutches in the ...
Rong Chai +3 more
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