Showing papers by "University of Warsaw published in 1983"

Yield estimation model for VLSI artwork evaluation

Abstract: In the letter a model which describes limitations of a manufacturing yield in terms of an IC artwork and a lithography characterisation is proposed. Density and distribution of diameters of defects present in the mask, as well as line-width fluctuations, are taken into account.

High-Energy Quasielastic Muon-neutrino n ---> mu- p Scattering in Deuterium

Abstract: We have studied the quasielastic reaction ..nu../sub ..mu../n..--> mu../sup -/p in an exposure of the Fermilab deuterium-filled 15-foot bubble chamber to a high-energy wide-band neutrino beam. From an analysis of the Q/sup 2/ distribution based on the standard V-A theory, the axial-vector mass in a dipole parametrization of the axial-vector form factor is determined to be M/sub A/ = 1.05/sub -0.16//sup +0.12/ GeV, consistent with the values previously reported from low-energy experiments.

Exact analysis of class E tuned power amplifier with only one inductor and one capacitor in load network

Abstract: Presents an exact analysis of that amplifier, an accurate and simple design procedure, and experimental results which confirm the theoretical analysis. The following performance parameters are determined for optimum operation with any switch duty ratio: the current and voltage waveforms, the peak values of collector current and collector-to-emitter voltage, the output power, the power-output capability, and the component values of the load network. The output harmonic spectrum is given for several values of switch duty ratio. The transistor power losses and collector efficiency are also estimated. The measured collector efficiency was over 95 percent with 3 W output power at 1 MHz, using a BSX60 TO-39 transistor.

Partial and robust linearization by feedback

Abstract: It is argued that if the nonlinearities in a system are mild, and the controller is sufficiently stabilizing, the inaccuracies of a linear model, which is often taken to be sufficient for a controller design, can be safely neglected. For systems with severe nonlinearity a linearizing technique is described, based on the change of state coordinates and nonlinear feedback; in the total context of a stable feedback design the linearization technique is considered robust. Furthermore, attention is paid to partial linearization using the same transformations. It is found that there always exist maximally linearizing transformations which are not necessarily unique.

Stochastic approximation method with gradient averaging for unconstrained problems

Abstract: A stochastic approximation algorithm is studied, in which random gradient estimates are averaged by an auxiliary, filter. Convergence of the algorithm is proved under a rather general noise condition. A practical version of the method is described and numerical results are given.

On homogeneous polynomials on a complex ball

Abstract: We prove that there exist «-homogeneous polynomials p„ on a complex d-dimensional ball such that II /»„ II „o = 1 and Ily7„ll2 * fn2~d. This enables us to answer some questions about Hp and Bloch spaces on a complex ball. We also investigate interpolation by «-homogeneous polynomials on a 2-dimensional complex ball. Introduction. The starting point of our investigation was a question asked by S. Waigner: Is the identity map from Hx(Bd) into Hx(Bd) (Bd is a unit ball in Cd), d > 1, a compact linear map. This question has a connection with the well-known open problem (cf. [5]): does there exist a nonconstant inner function on Bd, d > l?1 The existence of such an inner function would imply our Corollary 1.5, namely that this operator is not compact. We obtain this result by exhibiting «-homogeneous polynomials pn which in some respects resemble the monomials z" in the one-dimensional case (Theorem 1.2). We give two proofs of this theorem, one in §1 and the other at the end of §2. Those polynomials enable us to also answer a question of R. Timoney (Corollary 1.9). We hope that they will find some other applications. In §2 we investigate interpolating «-homogeneous polynomials on the unit sphere in two-dimensional complex space. The motivation for this study is the following well-known open problem (cf. [6]): does there exist a function 1, such that for every finite-dimensional Banach space X we have d(X, l^nX) = 1}. The point (1,0,... ,0) G Sd will be denoted by 1. On Sd we have the natural rotation-invariant probability measure a. Wn(Sd) will denote the space of all «-homogeneous polynomials on Cd restricted to Sd. On Wn(Sd) we will consider various norms. For f E Wn(Sd) we put 11/11^ = ilsd\fWd°iS)r/p if 1 " we obtain A/(l) = (P„f)(l)=f(i), so X = 1. This means that Pn is an orthogonal projection onto W2(Sd). Its norm as an operator on LJSd) equals aid, n)a(d,2n)-x xfn2~d. Before we start the proof of Theorem 1.2 let us recall some well-known notions concerning finite-dimensional Banach spaces. Let X, Y be finite-dimensional Banach spaces. We put X(*) = infill Til ■ \\S\\:X^Lxtx, TS = Id*, Lx is an arbitrary Ljuy-spacej and d(X, Y) = inf{||71 • lir-'ll: T: X -> Yis 1-1 and onto}. License or copyright restrictions may apply to redistribution; see http://www.ams.org/journal-terms-of-use HOMOGENEOUS POLYNOMIALS ON A COMPLEX BALL 109 The number A(A') is called a projection constant of X and d(X, Y) is called the Banach-Mazur distance between X and Y. It is well known and easy to see that (1) X(X) ^/«~. More information on this can be found in [6] and [4,22.1 and 28.1]. We will also use the following two lemmas. Lemma 1.3. inf{\\p\\2: p E W„(Sd) and H/HI«, = 1) = ya(d,2n). Proof. Since the spaces under consideration are finite dimensional, there exists a polynomial p0 realising the minimum. We can assume p0ii) — 1 = ll/Poll«,It is easily seen that Pin = -^r---f%o(h,ei9iz2,...,ea^zd)der-'ded_l = (S,ir. (2ir) •'o Jo Moreover, ||p\\2 « ||p0\\2 and \\p\\x = IIpQIIx = 1. Sincep0 was minimal we infer Il PII2 = II Po II2This proves the lemma. Lemma 1.4. dimW„(Sd) = a(d,2n)~x. Proof. It follows from Proposition 1.1 that dim Wn(Sd) = trace Pn. Since Pn is a projection its trace equals the square of its Hubert-Schmidt norm, which, as is well known, equals a(d,2n)-2f j \(S,V)\2"da(!;)da(Ti) = a(d,2n)-1. Now we are ready to prove the theorem. Proof of Theorem 1.2. We apply (1) for X = W2(Sd) and Y = Wn°°(Sd). Using (2), Proposition 1.1 and Lemma 1.4 we obtain (3) d{W2(Sd), W?iSd)) ^ X{W2(Sd))XiW-(Sd))-X > 2x~d(fr/2)]ia(d,2ny] . Let / denote the identity map from WTM(Sd) into W2(Sd). By the definition of the Banach-Mazur distance we have 11/II ■ III~x\\ > d(W2(Sd),WTM(Sd)). Lemma 1.3 gives || 7"11| = ]Ja(d, 2«)~ so by (3) we have \\I\\^2x'd^/2. This inequality proves the theorem. Remark. Actually d(W2(Sd), W„°°(Sd)) = \\I\\ ■ \\rx\\. This follows from [1, Lemma 4.6]. Corollary 1.5. id: Hx(Bd) -» Hx(Bd) is not a compact operator. Proof. Polynomials pn exhibited in Theorem 1.2 are orthogonal. Moreover by the Schwartz inequality, fW2~d tr4-d. This implies that id: Hx(Bd) -» Hx(Bd) is not a compact operator. License or copyright restrictions may apply to redistribution; see http://www.ams.org/journal-terms-of-use 110 J. RYLL AND P. WOJTASZCZYK Proposition 1.6. Let (nk) be a lacunary sequence of natural numbers and let p„k E W„k(Sd) be such that \\p„k\\x = 1 and II/>„J|, > c, k = 0,1,2.... Then there exist constants A and B such that (4) A-X(i\ak\2)l/1 <\\lakP„kj

Food of brook charr in extreme oligotrophic conditions of an alpine lake

Abstract: A stunted form of Salvelinus fontinalis has persisted since its introduction in 1948 in ultra oligotrophic Zielony Lake in the Tatra Mountains, southern Poland, despite extremely poor available food. The charr shifts from feeding on airborne insects to benthic chironomid larvae when the lake is frozen in October, and to the sole planktonic crustacean survivor (Cyclops abyssorum tatricus) when access to the sediments becomes difficult due to oxygen depletion in April–May. The plankton food resource enables the charr to survive till June, when the ice-cover breaks up. Due to charr predation the old Cyclops generation becomes extinct in May, but Cyclops eggs hatch after passing through the charr intestine unharmed. Each new Cyclops generation explodes due to the absence of cannibalistic adults, which have been removed by the charr, and persists in high densities until the next April–May when the egg-carrying females (highly selected by the charr) appear again to focus the charr attention on planktonic food resources.

A Regulative Theory Of Temperament

Abstract: A theory of temperament is presented which draws upon the tradition of neo-Pavlovian typology of the nervous system. Special attention is paid to temperament as one of the regulators of the relationship between humanity and environment, when the environment is treated as a source of stimulation. The main focus is upon temperamental characteristics associated with behaviour at the energetics level. This comprises two dimensions: reactivity and activity. A theoretical analysis of the two traits is conducted and their relationship with human behaviour is elaborated. A number of studies are discussed, illustrating the role of reactivity as one of the regulators of the individual's style of action and as a partner in the determination of preferences for situations and for behaviours of a given stimulatory potential. Finally, the paper provides a number of data exemplifying essential relations between temperament and personality. The interdependencies between both these phenomena are discussed in the light of the assumption that temperament should be regarded as a consequence of biological evolution and personality as a product of the social environment.

Charged-particle multiplicity distributions in. nu. n and. nu. p charged-current interactions

Abstract: Charged-hadron multiplicity distributions in $\ensuremath{ u}n$ and $\ensuremath{ u}p$ interactions are measured in an exposure of the Fermilab deuterium-filled 15-foot bubble chamber to a wide-band neutrino beam. Multiplicity moments are studied as functions of the invariant mass of the hadronic system $W$ in the range $1lWl15$ GeV. The mean multiplicities for both $\ensuremath{ u}n$ and $\ensuremath{ u}p$ are found to increase logarithmically with ${W}^{2}$ with identical slopes but slightly different intercepts. A linear rise of the dispersion $D$ with the mean multiplicity $〈{n}_{\mathrm{ch}}〉$ is observed with an approximate slope of 0.35. This value is similar to that found in ${e}^{+}{e}^{\ensuremath{-}}$ and $\overline{p}p$ annihilation and is much less than the asymptotic prediction of QCD. A close similarity between ${D}_{\ensuremath{-}}$ vs $〈{n}_{\ensuremath{-}}〉$ in $\ensuremath{ u}n$ and $\ensuremath{ u}p$ interactions is seen. Negative correlations between the multiplicity distributions in the forward and backward hadronic center-of-mass hemispheres are found and discussed.

Degradation and depolymerization of poly(propylene carbonate) by diethylzinc

Abstract: Poly(propylene carbonate) (PPC) was treated with diethylzinc in 1,4-dioxane solution at 30°C, Zn(C2H5)2 being used in excess or defficiency with regard to carbonate units. PPC was found to undergo degradation and depolymerization reactions, which were followed via the polymer intrinsic viscosity and the propylene carbonate yield. A model reaction between diethyl carbonate and diethylzinc was carried out too. From the results, a mechanistic view for both pathways, degradation and depolymerization, is proposed.