Results 81 to 90 of about 235,371 (297)
Proportional-Derivative Control of Stick-Slip Oscillations in Drill-Strings
MATEC Web of Conferences, 2018 Stick-slip oscillation in drill-string is a universal phenomenon in oil and gas drilling. It could lead to the wear of drill bit, even cause catastrophic failure of drill-strings and measurement equipment.
Lin Wei, Liu Yang
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Colden String Quartet, October 17, 1980
, 2019 Recorded during a live performance at Oakland Recital Hall, Western Michigan University, Kalamazoo, Michigan on Oct. 17, 1980, 8:00 p.m., program no. 27 of the School of Music's 1980-1981 season.Colden String Quartet (Marshall Meade and Mary Ann Sabato ...
Colden String Quartet
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World's fastest 10 000‐m breakthrough: The XY‐22 well redefines deep‐earth access in the Tarim Basin
Deep Underground Science and Engineering, EarlyView.The Tarim Basin in northwestern China hosts one of the world's deepest petroleum systems, exemplified by the XY‐22 ultra‐deep well (bottom depth: 11 116 m; ~220°C, ~145 MPa). This study integrates tectonic mapping, geological cross‐sections, ultraviolet fluorescence microscopy, and optical photothermal infrared (OPTIR) spectroscopy to characterize ...
Qingwen Tan +4 more
wiley +1 more source
Nonlinear Model and Qualitative Analysis for Coupled Axial/Torsional Vibrations of Drill String
Shock and Vibration, 2016 A nonlinear dynamics model and qualitative analysis are presented to study the key effective factors for coupled axial/torsional vibrations of a drill string, which is described as a simplified, equivalent, flexible shell under axial rotation.
Fushen Ren +4 more
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, 1992 This invention is comprised of a drill string enclosure which consists of six component parts, including; a top bracket, an upper acrylic cylinder, an acrylic drill casing guide, a lower acrylic cylinder, a bottom bracket, and three flexible ducts.
Wiersholm, O. +3 more
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ENERGY &ENVIRONMENTAL MATERIALS, EarlyView.Perovskite/silicon tandem solar cells offer efficiencies beyond 30%, yet conventional architectures face trade‐offs between optical performance and current matching. Three‐terminal tandems employing silicon back‐contact bottom cells eliminate the current‐matching constraint while minimizing optical losses, offering superior energy yield under real ...
Yunhao Fan +4 more
wiley +1 more source
An integrated model for drill-string dynamics
, 1999 The vibrational states experienced by the active components of a drilling assembly such as that found in the oil or gas industry are discussed in the context of an integrated mathematical model. The work is motivated by the need to understand the complex
Wang, Charles, Tucker, Robin
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Shiyou jixieIn response to the demand for plugging old wells of CO2 gas storage under the carbon peak and carbon neutrality goals， to address the challenges of deploying wireline logging tools to the bottomhole of highly-deviated and complex-structure wells during ...
Ren Xianke +6 more
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Drill String Drag and Torque Test Device Design
Shiyou jixie, 2019 The existing drag and torque theoretical model has many assumptions, leading to a large difference between the calculated value and the true value, which seriously restricts the study of the mechanical behavior of the drill string and the optimization of
吴泽兵 +4 more
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Syzygy: The Concord String Quartet
, 2008 String Quartet No. 4 (1978), George Rochberg (b. 1918) -- String Quartet No. 3 (1981), Jacob Druckman (b. 1928) -- String Quartet No.
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