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981.
Let F a two-alternative voting rule and GF the subgroup of permutations of the voters under which F is invariant. Group theoretic properties of GF provide information about the voting rule F. In particular, sets of imprimitivity of GF describe the ‘committee decomposition’ structure of F and permutation group transitivity of GF (equipotency) is shown to be closely connected with equal distribution of power among the voters. If equipotency replaces anonymity in the hypotheses of May's theorem, voting rules other than simple majority are possible. By combining equipotency with two additional social choice conditions a new characterization of simple majority rule is obtained. Equipotency is proposed as an important alternative to the more restrictive anonymity as a fairness criterion in social choice.  相似文献   
982.
Self-affine multiplicity scaling is investigated in the framework of two-dimensional factorial moment methodology using the concept of the Hurst exponent (H). Our investigation on experimental data of the target-evaporated slow particles emitted in 32S-AgBr interactions at 200 AGeV and 28Si-AgBr interactions at 14.5 AGeV reveals that a better power law behavior is exhibited in self-affine analysis than self-similar analysis. This work shows a clear evidence of self-affine target fragmentation. Received: 22 October 2001 / Accepted: 6 March 2002  相似文献   
983.
Solutions of constrained minimization problems give rise to Lagrange multiplier rules. In this paper, we show that a simple condition on a specific constraint implies that the associated coefficient in the Lagrange multiplier rule is not zero. We conclude with an example which shows that such knowledge increases the information available about the solution of a problem of minimal curvature.This work supported in part by NSF Grant No. MCS-75-05581-A01.  相似文献   
984.
D K Choudhury 《Pramana》1976,7(5):307-312
Using Glauber’s theory of eikonal approximation, an algebraic representation of the broken Zweig rule in the constituent quark model is obtained. Null plane language is then elaborated. It is pointed out that the exotic current associated with the disconnected quark diagrams, which break the Zweig rule, can have canonical dimension.  相似文献   
985.
A simple distribution-free method is proposed for directly estimating and updating a criterion function without recourse to prior state space specification, updated state probabilities, and Bayes' rule. Optimality properties and efficiency advantages of the method are illustrated in terms of a two-armed bandit problem. The relationship between direct criterion function estimation and Kalman-Bucy filtering is clarified.  相似文献   
986.
The aim of the paper is to get an estimation of the error of the general interpolation rule for functions which are real valued on the interval [—a, a],a (0,1), have a holomorphic extension on the unit circle and are quadratic integrable on the boundary of it. The obtained estimate does not depend on the derivatives of the function to be interpolated. The optimal interpolation formula with mutually different nodes is constructed and an error estimate as well as the rate of convergence are obtained. The general extremal problem with free weights and knots is solved.  相似文献   
987.
Two binuclear bis(tricarbonyliron) title complexes with N(2)Fe(2) tetrahedral cores, 1 and 2, respectively, which show different molecular folding resulting from the appearance (in 1), and absence (in 2) of the N-N sigma-bond, were compared in terms of mass spectral fragmentation routes. A multipath fragmentation noted for the molecule 1 revealing internal stress contrasts with the single-route fragmentation of 2. The fragmentation paths resulting from the admixtures were defined and analyzed from the fragment ion B/E and parent ion B(2)/E linked scan spectra.  相似文献   
988.
We prove the completeness and decidability of the Hornlike sequents, specifically, the socalled D2sequents (of the firstorder linear temporal logic) considered in the author's paper [Lith. Math. J., 41(3), 266–281 (2001)]. In this paper, with the help of the infinitary calculus GL, grounded by the author in his earlier papers, for D2sequents we construct a D2Sat calculus of the socalled saturated type consisting of decidable deductive procedures replacing the omegarule for the always operator. In the present paper, in order to prove the completeness and decidability of the calculus D2Sat, we construct the socalled invariant decidable calculus D2IN. We prove the equivalence of the calculi D2IN, D2Sat, and G L ** for the socalled saturated D2sequents. From this equivalence, by reducing an arbitrary D2sequent to a saturated D2sequent, and also from the completeness of the G L ** calculus and decidability of the invariant calculus D2IN, we deduce the completeness and decidability of the calculus D2Sat in the class of D2sequents.  相似文献   
989.
Copolymers of vinyl acetate and methacrylonitrile were prepared by free‐radical polymerization in the presence of the chain‐transfer agent (CTA) ethyl‐α‐ (t‐butanethiomethyl)acrylate. Molecular weight measurements showed that the chain‐transfer constants increased with the vinyl acetate content of the comonomer mixture, ranging from 0.42 for methacrylonitrile to 6.3 for the copolymerization of a vinyl acetate‐rich monomer mix (89/11). The bulk copolymer composition was not appreciably affected by the amount of CTA used in the copolymerization. The efficiency of the addition–fragmentation mechanism in producing specifically end‐functionalized copolymers was investigated with 1H NMR spectroscopy. Spectral peaks consistent with all the expected end groups were observed for all comonomer feeds. Peaks consistent with other end groups were also observed, and these were particularly prominent for copolymers made with lower CTA concentrations. At the highest concentrations used, quantitative measurements of end‐group concentrations indicated that 70–80% of the end groups were those expected on the basis of the addition–fragmentation chain‐transfer mechanism. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2911–2919, 2001  相似文献   
990.
Summary: A novel method combining RAFT polymerization with pulsed‐laser initiation for determining chain‐length dependent termination rate coefficients, kt, is presented. Degenerative chain‐transfer in RAFT enables single‐pulse pulsed‐laser polymerization (SP‐PLP) traces to be measured on systems with a narrow radical distribution that remains essentially unchanged during the experiment. SP‐PLP‐RAFT experiments at different polymerization times allow for determining kt as a function of chain length via classical kinetics assuming chain‐length independent kt.

Single‐pulse pulsed‐laser polymerization trace for BMPT‐mediated RAFT polymerization of butyl acrylate.  相似文献   

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