Students are often suggested to provide feedback to teachers on lectures, learning materials and tests among other things. While such information can considerably improve the learning process it is necessary to find an effective way to obtain feedback and at the same time decrease the amount of time students use to deliver it. This article is a step towards extracting maximal knowledge with min...

10. In this note we consider complete Riemannian manifolds with Ricci curvature bounded from below. The well-known theorems of Myers and Bishop imply that a manifold M n with Ric ~ n 1 satisfies diam(1l1n) ~ diam(Sn(I)), Vol(Mn) ~ Vol(Sn(I)). It follows from [Ch] that equality in either of these estimates can be achieved only if M n is isometric to Sn (1). The natural conjecture is that a manif...

We show that the maximal number of singular moves required to pass between any two regularly homotopic plane or spherical curves with at most n crossings grows quadratically with respect to n. Furthermore, for any two regularly homotopic curves with at most n crossings, there exists such a sequence of singular moves, satisfying the quadratic bound, for which all curves along the way have at mos...

The effects of zein ratio, concentration of glycerol, liquid-solid ratio, ethanol concentration, pH and heat-treatment temperature on the properties of zein/wheat gluten composite films were researched. The results showed that elongation (E) increased with an increase in glycerol or ethanol concentrations, but it first increased and then decreased with increasing zein/wheat gluten ratio, heat-t...

Jech and Shelah [2] studied full reflection below אω, and produced a model in which the extent of full reflection is maximal in a certain sense. We produce a model in which full reflection is maximised in a different direction.

We determine the maximal set of moves for 2-pile take-away games with prescribed P -positions (bαnc, bβnc) for n ∈ Z≥1 where α ∈ (1, 2) is irrational, 1/α+1/β = 1. This was done in [3] for the special case α = golden ratio. We generalize the infinite Fibonacci word to an infinite wordW with alphabet Σ = {a, b}, in which α replaces the golden ratio, and we analyze the set {s ∈ Z≥0 : W(s) = b, W(...

Let H be the Heisenberg group and let μt be the normalized surface measure for the sphere of radius t in R. Consider the maximal function defined by Mf = supt>0 |f ∗μt|. We prove for n ≥ 2 that M defines an operator bounded on L(H) provided that p > 2n/(2n − 1). This improves an earlier result by Nevo and Thangavelu, and the range for L boundedness is optimal. We also extend the result to a mor...

Let X be a compact set in the z-plane. We are interested in two function spaces associated with X: C(X) — space of all continuous complex-valued functions on X. P(X) =space of all uniform limits of polynomials on X. Thus a function ƒ on X lies in P{X) if there exists a sequence {Pn} of polynomials converging to ƒ uniformly on X. Clearly P(X) is part of C(X). QUESTION I. When is P(X) = C(X)t i.e...

In the present paper we start the systematic explicit construction of invariant differential operators by giving explicit description of one of the main ingredients the cuspidal parabolic subalgebras. We explicate also the maximal parabolic subalgebras, since these are also important even when they are not cuspidal. Our approach is easily generalised to the supersymmetric and quantum group sett...