Results 91 to 100 of about 32,232 (297)
Weeds in a changing climate: Competitors or service plants?
PLANTS, PEOPLE, PLANET, EarlyView.Reducing herbicide use and preparing agroecosystems for climate change are two top priorities on the global policy agenda. Here, we explore whether these two challenges can be tackled simultaneously. While weeds are generally considered a threat to crop production, we show that weeds can help overcome climate change challenges in agroecosystems ...
Marie J. Zwetsloot +12 more
wiley +1 more source
A theoretical study of fluid forces on a centrifugal impeller rotating and whirling in a vaned diffuser [PDF]
The fluid forces on a centrifugal impeller rotating and whirling in a vaned diffuser are analyzed on the assumption that the number of impeller and diffuser vanes is so large that the flows are perfectly guided by the vanes.
Acosta, Allan J. +2 more
core +1 more source
Sliding Mode Control in Aerospace Applications: A Survey
International Journal of Robust and Nonlinear Control, EarlyView.ABSTRACT Sliding mode control (SMC) enjoys robustness to matched and unmatched (in the case of minimum phase input‐output dynamics) bounded perturbations, and finite time convergence. Second‐order and higher‐order sliding mode control systems (2‐SMC/HOSMC) retain all the advantages of sliding mode control, but in addition can be applied to systems of ...
Yuri Shtessel, Christopher Edwards
wiley +1 more source
Evaluation of a stall-flutter spring-damper pushrod in the rotating control system of a CH-54B helicopter [PDF]
Results of a design and flight test program conducted to define the effect of rotating pushrod damping on stall-flutter induced control loads are presented.
Adams, D. O. +2 more
core +1 more source
Growth of Black Holes in the interior of Rotating Neutron Stars
, 2013 Mini-black holes made of dark matter that can potentially form in the interior of neutron stars have been always thought to grow by accreting the matter of the core of the star via a spherical Bondi accretion.
Kouvaris, Chris, Tinyakov, Peter
core +1 more source
Systems Engineering, EarlyView.ABSTRACT Digital Engineering (DE) transformation represents a paradigm shift in systems engineering (SE), aiming to integrate heterogeneous analytical models and digital artifacts into an authoritative source of truth to improve traceability and lifecycle management.
Md Doulotuzzaman Xames, Taylan G. Topcu
wiley +1 more source
AIP Advances, 2019 This paper presents an investigation into the interaction between a low-speed compressor and a circumferential inlet distortion, through high-resolution measurements and full annulus Detached-Eddy simulation.
Youtian Zhou, Jun Li, Guoxing Song
doaj +1 more source
Robustness of rotating stall control for axial-flow compressors
Proceedings of the 2002 American Control Conference (IEEE Cat. No.CH37301), 2002 Feedback control has been pursued to address the rotating stall problem in axial flow compressors in order to extend the stable operating range and to improve engine performance. These controllers guarantee the stability of the bifurcated operating solution near the stall point.
Ali Tahmasebi, Xiang Chen
openaire +2 more sources
TESOL Quarterly, EarlyView.Abstract Previous research demonstrated that communication anxiety reduces L2 learners' willingness to communicate and communication frequency, but left unexplored its impact on performance. The current mixed‐methods study investigated factors impacting L2 communication skills.
Debra M. Hardison
wiley +1 more source
Advances in Mechanical Engineering, 2017 Numerical simulation has been conducted on a transonic contra-rotating axial compressor to investigate the shock wave and flow characteristics under various operation conditions.
Hanru Liu +3 more
doaj +1 more source