Results 41 to 50 of about 18,302,605 (160)
New views of some invariants associated with the Cartesian 2D velocity gradient tensor
Quarterly Journal of the Royal Meteorological Society, EarlyView.Vorticity and divergence of horizontal flow are fundamental quantities in meteorology; both are linear functions of the four elements of the 2D velocity gradient tensor and both are formally unchanged under coordinate rotation. We explore four quadratic functions of the elements that are geometrically invariant in this sense, finding some novel ...
I. Roulstone, S. A. Clough, A. A. White
wiley +1 more source
Optimal Homogeneous ℒp$$ {\boldsymbol{\mathcal{L}}}_{\boldsymbol{p}} $$‐Gain Controller
International Journal of Robust and Nonlinear Control, EarlyView.ABSTRACT Nonlinear ℋ∞$$ {\mathscr{H}}_{\infty } $$‐controllers are designed for arbitrarily weighted, continuous homogeneous systems with a focus on systems affine in the control input. Based on the homogeneous ℒp$$ {\mathcal{L}}_p $$‐norm, the input–output behavior is quantified in terms of the homogeneous ℒp$$ {\mathcal{L}}_p $$‐gain as a ...
Daipeng Zhang +3 more
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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
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Two contributions to the representation theory of algebraic groups [PDF]
, 2002 Let V be a nite dimensional complex vector space. A subset X in V has the separation property if the following holds: For any pair l, m of linearly independent linear functions on V there is a point x in X such that l(x) = 0 and m(x) 6= 0.
Baur, Karin
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Sliding Motions on Non‐Euclidean State Spaces: A Differential‐Geometric Perspective
International Journal of Robust and Nonlinear Control, EarlyView.ABSTRACT This paper extends sliding‐mode control theory to nonlinear systems evolving on smooth manifolds. Building on differential geometric methods, we reformulate Filippov's notion of solutions, characterize well‐defined vector fields on quotient spaces, and provide a consistent geometric definition of higher‐order sliding modes.
Fernando Castaños
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Special Reductive Groups Over An Arbitrary Field
A linear algebraic group G defined over a field k is called special if every G-torsor over every field extension of k is trivial. In 1958 Grothendieck classified special groups in the case where the base field is algebraically closed.
Huruguen, Mathieu
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Levels and sublevels of composition algebras over p-adic function fields [PDF]
, 2008 In [O'S], the level and sublevel of composition algebras are studied, wherein these quantities are determined for those algebras defined over local fields.
Van Geel, Jan +3 more
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An Innovative Approach to Multi‐Valued Logic
IEEJ Transactions on Electrical and Electronic Engineering, EarlyView.The current generation of computer systems operates on the principles of binary logic, which encompasses both logical and arithmetic operations. However, silicon technology has reached its peak performance, prompting researchers to explore alternative methods for enhancing computational efficiency. One such method is the adoption of Multi‐Valued Logic (
Ali Mokhtari, Peyman Kabiri
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Quadratic Forms and Linear Algebraic Groups [PDF]
, 2013 Topics discussed at the workshop “Quadratic Forms and Linear Algebraic Groups” included besides the algebraic theory of quadratic and Hermitian forms and their Witt groups several aspects of the theory of linear algebraic groups and homogeneous varieties,
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Research on Ultra‐Wideband Pulse Current Method for DC Partial Discharge Measurement
High Voltage, EarlyView.ABSTRACT The conventional pulse current method is commonly used in AC or DC withstand voltage tests with partial discharge (PD) monitoring. Because of its relatively narrow measurement bandwidth, this method tends to ignore critical information in PD waveforms, making it difficult to eliminate pulse‐type interference under DC voltage conditions, where ...
Kaining Hou +4 more
wiley +1 more source