Results 71 to 80 of about 22,977 (217)

Improved stiff string torque and drag prediction using a computationally efficient contact algorithm

Mathematical and Computer Modelling of Dynamical Systems
Due 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
doaj   +1 more source

Parametric Studies on Drill String Dynamics Drill mud damping effects with drive speed variation

, 2018
—Complicated behavior of oilwell drill string with both torsional and lateral whirl vibrations are explored numerically and experimentally within this paper.
M. Alqaradawi, M. Kanzari, Balachandran Balakumar   +2 more
semanticscholar   +1 more source

The effectiveness of implementation intentions in children: A systematic review and meta‐analysis

British Journal of Psychology, EarlyView.
Abstract Self‐regulation abilities in childhood are important for long‐term academic achievement and healthy development. As self‐regulatory abilities are still developing, ‘simple’ interventions are needed to foster self‐regulation. Implementation intentions are simple plans that could promote goal achievement in children.
Jasmin Breitwieser, Tilman Reinelt
wiley   +1 more source

Influences of Excitation Force Forms of the Hydraulic Oscillator on Drag Reduction Efficiency

Shiyou jixie, 2023
The excitation force forms of the hydraulic oscillator have been rarely reported.Considering the nonlinear effect of frictional forces, a dynamics model of the drill string equipped with the hydraulic oscillator was built by introducing the initial ...
Shi Xiaolei, Huang Wenjun, Gao Deli
doaj  

ReTrace: Interactive Visualizations for Reasoning Traces of Large Reasoning Models

Computer Graphics Forum, EarlyView.
Abstract Recent advances in Large Language Models have led to Large Reasoning Models, which produce step‐by‐step reasoning traces. Such traces may offer insight into how models think, improving explainability and clarifying the underlying process. These traces, however, are often verbose and complex, making them cognitively demanding to comprehend ...
L. Felder, J. Miller, M. Wallinger, S. G. Kobourov, C. Chen   +4 more
wiley   +1 more source

Study on Fatigue Life of BHA based on Drill String Dynamics

Shiyou jixie, 2022
The bottom hole assembly(BHA)is prone to fatigue failure due to long-term severe vibration in the wellbore.Most studies use the differential equation to calculate the fatigue life of BHA,which has a large difference from the actual working conditions on ...
Mao Liangjie, Gan Lunke, Xing Xuesong, Li Juan   +3 more
doaj  

Effects of restoration practices on biodiversity in temperate and boreal forests

Conservation Biology, EarlyView.
Abstract Several restoration practices are used to mitigate and compensate for the negative effects of large‐scale forestry on biodiversity in temperate and boreal forests. A comprehensive synthesis of the benefits of these practices across taxa is missing. We conducted a systematic review and meta‐analysis on this topic.
Malin Tälle, Thomas Ranius, Julia Koricheva   +2 more
wiley   +1 more source

Collagen Type VI Alpha 1 as a Regulator of Redox Homeostasis in Antioxidant‐Enhanced Osteogenesis of Dental Stem Cells

Cell Proliferation, EarlyView.
Under physiological conditions, NAC activates the PI3K‐AKT‐COL6A1 axis to sustain redox balance and enhance osteogenesis. COL6A1 deficiency, however, compromises this axis, inducing oxidative stress and impairing NAC's osteogenic efficacy. ABSTRACT Alveolar bone injury represents a prevalent clinical challenge in dentistry, for which stem cell‐based ...
Zhaosong Meng, Jiacheng Liu, Yue Zhang, Ruimeng Yang, Jingyi Zhang, Haosun Yang, Zheng Wang, Ran Wei, Zhe Li, Shuling Guo, Lizhi Hu, Lei Sui   +11 more
wiley   +1 more source

Research on Mechanism of Stick-Slip Vibration Induced by Friction between Drill String and Borehole Wall in Horizontal Well

Shiyou jixie, 2021
The stick-slip vibration of the horizontal well drill string system seriously threatens the safety of downhole drill strings and tools, reduces the drilling efficiency of the horizontal section, making the drill bit fail prematurely.
Zhu Jieran, Zou Deyong, Li Guangquan, Yang Ningning, Yang Quanjin, Lin Wei   +5 more
doaj  

Effects of axial impact load on the dynamics of an oilwell drillstring

Advances in Mechanical Engineering, 2019
This article studies the dynamics of oilwell drillstring under large and small axial impact loads. For the case of large impact load, the drillstring is regarded as a continuous bar under the impact load of a falling mass, and the energy conservation ...
Liping Tang, Xiaohua Zhu, Hongzhi Lin
doaj   +1 more source