Results 241 to 250 of about 668,078 (284)
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1993
Things change. We describe these changes mathematically in terms of derivatives. A change of a variable, Φ, with respect to time is simply dΦ/dt. If the variable is also a function of position, the change in the variable depends on the direction. ∂Φ/ ∂x may be different from ∂Φ/ ∂y.
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Things change. We describe these changes mathematically in terms of derivatives. A change of a variable, Φ, with respect to time is simply dΦ/dt. If the variable is also a function of position, the change in the variable depends on the direction. ∂Φ/ ∂x may be different from ∂Φ/ ∂y.
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Nonregular Pseudo-Differential Operators
Zeitschrift für Analysis und ihre Anwendungen, 1996We study the boundedness properties of pseudo-differential operators a(x, D) and their adjoints a(x, D)* with symbols in a certain vector-valued Besov space on Besov
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Homogenization of Differential Operators
Acta Mathematicae Applicatae Sinica, English Series, 2002zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Differential Operators and Differential Modules
2003In this chapter k is a differential field such that its subfield of constants C is different from k and has characteristic 0. The skew (i.e., noncommutative) ring D :=k[∂] consists of all expressions L :=a n ∂ n + ⋯ + a1∂ + a0 dot with n ∈ Z, n ≥ 0 and all a i ∈ k. These elements L are called differential operators.
Marius van der Put, Michael F. Singer
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ON SECOND ORDER DIFFERENTIAL OPERATORS
The Annals of Mathematics, 1955Nevertheless, (1.2) is meaningful only under differentiability conditions which are unnatural for (1.1). An adjoint to (1.1) exists always, but it cannot be written in terms of derivatives with respect to x. The characteristic property of A appears to be (1) that it is of local character, (2) that whenever f has a local minimum at xo and f(xo) = 0 ...
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A new selection operator for differential evolution algorithm
Knowledge-Based Systems, 2021Zhiqiang Zeng, Tao Chen
exaly
Differential evolution algorithm with fitness and diversity ranking-based mutation operator
Swarm and Evolutionary Computation, 2021Zhibin Pan, Zhaoqi Gao
exaly
Differentials and Differential Operations
2017Bernd Steinbach, Christian Posthoff
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