DEL

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DEL

Abbreviation for:
deletion
deltoid
delusion
Departmental Expenditure Limit
References in periodicals archive ?
(ii) The right (nabla) CFC fractional difference has the following form:
In this paper, we are concerned with the the relation between the positivity of the vth order nabla q-fractional difference and the monotonicity and convexity of f (t).
(1) (Fractional nabla sum) [11]: the ath-order nabla sum of u is given by
To the best of the author's knowledge there is no known technique to obtain results from the nabla calculus directly from results on the delta calculus and vice versa.
First we formulate a theorem which gives a relationship between the delta and nabla derivatives.
Unlike Maxwell's previous paper on electromagnetic fields ("On Physical Lines of Force," Philosophical Magazine, 1861-62), mechanical models for the connections between electromagnetic fields are largely absent from his Treatise, in which he uses scalars, vectors, and nablas as we do today except for a slight difference in notation for the divergence and curl of vectors.
For f : T [right arrow] R and t [member of] [T.sub.k] define the nabla derivative of f at t denoted [f.sup.[nabla]] (t) to be the number (provided it exists) with the property that given any [epsilon] > 0, there is a neighborhood U of t such that
where [[nabla].sub.t] stands for the tangential components of the nabla operator.
The position vector, R, and the operator nabla, [nabla], are presentable as