Results 41 to 50 of about 180,798 (213)

Chironomid‐based summer temperature reconstruction of the Eemian–Weichselian transition at Lichtenberg, northern Germany

Boreas, EarlyView.
Understanding the temperature variability of past interglacial cycles is essential to predict future climates. We present a new summer temperature reconstruction, based on the subfossil chironomid record from a small palaeolake adjacent to the Middle Palaeolithic site of Lichtenberg, northern Germany. The record spans from the Saalian late glacial over
Sonja Rigterink, Bartosz Kotrys, Michael Hein, Xuan Li, Neda Rahimzadeh, Agnieszka Gruszczyńska, Marcel Weiss, Brigitte Urban, David Colin Tanner, Tobias Lauer, Antje Schwalb   +10 more
wiley   +1 more source

CFO overconfidence, environmental violations, and firm performance. The moderating role of constituency statutes

European Management Review, EarlyView.
Abstract This study examines the relationship between Chief Financial Officer (CFO) overconfidence and firm performance through the lens of environmental violations and constituency statutes. Drawing on stakeholder and upper echelons theories, we find that firms with overconfident CFOs are more likely to commit environmental violations, which ...
Panagiotis Andrikopoulos, Shee‐Yee Khoo, Patrycja Klusak, Yurtsev Uymaz, Huong Vu   +4 more
wiley   +1 more source

Reengaging Criminology in Regulation and Governance: A Synergistic Research Agenda on Regulatory Guardianship

Regulation &Governance, EarlyView.
ABSTRACT Recent literature calls for scholars to bridge the divide that has emerged between criminology and regulation and governance. In the current work, we propose that criminological opportunity theories provide one fruitful pathway to that end.
Carole Gibbs, Fiona Chan, Rachel Boratto, Tyler Hug   +3 more
wiley   +1 more source

Biostratigraphy of Eocene to Oligocene deep-water agglutinated foraminifers in the red clays from Site 767, Celebes Sea [PDF]

, 1991
Deep-water agglutinated foraminifers were examined from reddish brown claystones comprising lithologic Unit 4 of Ocean Drilling Program Holes 767B and 767C. The biostratigraphy of deep-water agglutinated foraminifers in this unit indicates an Eocene to
Huang, Zehui, M.A. Kaminski, Z. Huang, Kaminski, M.A., Kaminski, Michael A., Huang, Z.   +5 more
core   +1 more source

The quantitative description of gas-cut degree in deepwater drilling

Petroleum Exploration and Development, 2016
Through the analysis of gas-cut features in deepwater drilling and shortages of existing gas-cut detection methods, the feasibility of early detection of gas cut at the bottom of riser was demonstrated, and a method was proposed for quantitative ...
Yuqiang XU, Zhichuan GUAN, Huizeng ZHANG, Hongning ZHANG   +3 more
doaj   +1 more source

Wellbore multiphase flow behaviors during gas invasion in deepwater downhole dual-gradient drilling based on oil-based drilling fluid

Energy Reports, 2022
Knowledge of wellbore multiphase flow characteristics is important for early gas invasion identification and treatment, especially in oil-based drilling fluid.
Hongwei Yang, Jun Li, Geng Zhang, Hui Zhang, Boyun Guo, Wang Chen   +5 more
doaj   +1 more source

Physics‐Constrained Variational Autoencoder for Uncertainty Quantification of Full Waveform Inversion

Journal of Geophysical Research: Machine Learning and Computation, Volume 3, Issue 5, October 2026.
Abstract We propose a variational autoencoder framework to directly assess uncertainties in subsurface models produced by single‐ and multiparameter full waveform inversion (FWI). The new method does not require pretraining on labeled data, thus it significantly reduces computational cost and storage requirements.
Abdelrahman Elmeliegy, Mrinal K. Sen, Arnab Dhara, Jennifer Harding, Hongkyu Yoon   +4 more
wiley   +1 more source

Numerical Investigation of Wellbore Stability in Deepwater Shallow Sediments

Geofluids, 2021
An elaborate poro-elastoplastic numerical model has been developed in this paper to explore the stability characteristics of wellbore in shallow sediments of deepwater oil/gas wells.
Wei Liu, Hai Lin, Hailong Liu, Chao Luo, Guiping Wang, Jingen Deng   +5 more
doaj   +1 more source

An Amphiphilic Multiblock Polymer as a High-Temperature Gelling Agent for Oil-Based Drilling Fluids and Its Mechanism of Action

Gels, 2023
Oil-based drilling fluids are widely used in challenging wells such as those with large displacements, deepwater and ultra-deepwater wells, deep wells, and ultra-deep wells due to their excellent temperature resistance, inhibition properties, and ...
Yinbo He, Mingliang Du, Jing He, Haiyang Liu, Yanhua Lv, Lei Guo, Peng Zhang, Yunhai Bai   +7 more
doaj   +1 more source

Flow Characteristics and Response Surface Methodology‐Based Pressure‐Loss Prediction Models for the Reverse Circulation Converter in Double‐Wall Drill Pipes

Energy Science &Engineering, Volume 14, Issue 9, Page 4282-4299, September 2026.
Flow characteristics and pressure loss mechanisms of a reverse circulation converter in dual‐wall drill pipes are systematically investigated using CFD and response surface methodology. The results reveal the dominant role of inertial dissipation and provide a predictive framework for optimizing converter design and operational parameters. ABSTRACT The
Mingming Geng, Hui Zhang, Junpeng Li, Baokang Wu, Geng Zhang, Xinrui Wang, Jintao An, Long Chen, Yiming Ma   +8 more
wiley   +1 more source