Results 81 to 90 of about 9,449 (231)
Control of a class of multibody underactuated mechanical systems with discontinuous friction using sliding-mode [PDF]
, 2016 This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.This paper studies sliding-mode control of a class of multibody underactuated systems with discontinuous friction presenting on the ...
Liu, Y
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Advances in Mechanical Engineering, 2019 Stick–slip vibration is common in the oil well drilling process and is detrimental to down-hole equipment and drilling efficiency. In recent years, a new type of drilling technology, torsional impact drilling, has been developed to mitigate the stick ...
Liping Tang, Wei He, Xiaohua Zhu
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Xibei Gongye Daxue Xuebao, 2019 Exploration of oil or gas wells is usually carried out by using drilling system. When the kilometers of drilling system is externally disturbed, the drilling system is prone to undesired stick-slip vibration of the drill-string.
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Самовозбуждение крутильных колебаний колонн глубокого бурения [PDF]
, 2009 Поставлена задача о самовозбуждении упругих волновых крутильных колебаний вращающейся бурильной колонны в результате фрикционного взаимодействия ее долота со скальной породой на дне глубокой скважины.
Гуляев, В.И. +2 more
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Modeling and control of drillstring dynamics for vibration suppression [PDF]
, 2019 Drill-string vibrations could cause fatigue failure to downhole tools, bring damage to the wellbore, and decrease drilling efficiency; therefore, it is important to understand the drill-string dynamics through accurately modeling of the drill-string and ...
Feng, Tianheng
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Maximum, Minimum, and Current Temperature Protocol [PDF]
, 2003 The purpose of this activity is to measure air (and optionally soil) temperature within one hour of solar noon and the maximum and minimum air temperatures for the previous 24 hours. Intended outcomes are that students will learn to read minimum, maximum,
The GLOBE Program, UCAR (University Corporation for Atmospheric Research)
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, 2014 The present paper is concerned with the formulation of new assembly methods of bi-material tensegrity prisms, and the experimental characterization of the compressive response of such structures.
Amendola, Ada +4 more
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Torsional stick-slip vibrations and multistability in drill-strings
Applied Mathematical Modelling, 2019 El modelo generalizado de parámetros concentrados del sistema de sarta de perforación se estudia en este documento para proporcionar una comprensión fundamental de las vibraciones torsionales de palillo-deslizamiento en la perforación de fondo de pozo.
Yang Liu +3 more
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Study on lateral vibration characteristics of BHA with double-span drill collar
Advances in Mechanical EngineeringThe severe vibration of BHA directly affect the drilling efficiency, borehole trajectory, and wellbore quality. Therefore, it is crucial for developing dynamic mechanics of drill string system by studying the mechanical behavior of BHA.
Zuwen Tao +7 more
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Microgravity: A Teacher's Guide With Activities in Science, Mathematics, and Technology [PDF]
, 1997 The purpose of this curriculum supplement guide is to define and explain microgravity and show how microgravity can help us learn about the phenomena of our world.
Rogers, Melissa J. B. +2 more
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