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21.
We consider the problem of monotonicity testing over graph products. Monotonicity testing is one of the central problems studied in the field of property testing. We present a testing approach that enables us to use known monotonicity testers for given graphs G1, G2, to test monotonicity over their product G1 × G2. Such an approach of reducing monotonicity testing over a graph product to monotonicity testing over the original graphs, has been previously used in the special case of monotonicity testing over [n]d for a limited type of testers; in this article, we show that this approach can be applied to allow modular design of testers in many interesting cases: this approach works whenever the functions are boolean, and also in certain cases for functions with a general range. We demonstrate the usefulness of our results by showing how a careful use of this approach improves the query complexity of known testers. Specifically, based on our results, we provide a new analysis for the known tester for [n]d which significantly improves its query complexity analysis in the low‐dimensional case. For example, when d = O(1), we reduce the best known query complexity from O(log 2n/ε) to O(log n/ε). © 2008 Wiley Periodicals, Inc. Random Struct. Alg., 2008 相似文献
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linear array network consists of k+1 processors with links only between and (0≤i<k). It is required to compute some boolean function f(x,y) in this network, where initially x is stored at and y is stored at . Let be the (total) number of bits that must be exchanged to compute f in worst case. Clearly, , where D(f) is the standard two-party communication complexity of f. Tiwari proved that for almost all functions and conjectured that this is true for all functions.
In this paper we disprove Tiwari's conjecture, by exhibiting an infinite family of functions for which is essentially at most . Our construction also leads to progress on another major problem in this area: It is easy to bound the two-party communication
complexity of any function, given the least number of monochromatic rectangles in any partition of the input space. How tight
are such bounds? We exhibit certain functions, for which the (two-party) communication complexity is twice as large as the best lower bound obtainable this way.
Received: March 1, 1996 相似文献
26.
Dr. Yizhan Wang Dr. Manoj Raula Prof. Yifeng Wang Dr. Offer Zeiri Dr. Sourav Chakraborty Gal Gan-Or Eyal Gadot Prof. Ira A. Weinstock 《Angewandte Chemie (International ed. in English)》2017,56(25):7083-7087
The controlled assembly of gold nanoparticles (AuNPs) with the size of quantum dots into predictable structures is extremely challenging as it requires the quantitatively and topologically precise placement of anisotropic domains on their small, approximately spherical surfaces. We herein address this problem by using polyoxometalate leaving groups to transform 2 nm diameter gold cores into reactive building blocks with hydrophilic and hydrophobic surface domains whose relative sizes can be precisely tuned to give dimers, clusters, and larger micelle-like organizations. Using cryo-TEM imaging and 1H DOSY NMR spectroscopy, we then provide an unprecedented “solution-state” picture of how the micelle-like structures respond to hydrophobic guests by encapsulating them within 250 nm diameter vesicles whose walls are comprised of amphiphilic AuNP membranes. These findings provide a versatile new option for transforming very small AuNPs into precisely tailored building blocks for the rational design of functional water-soluble assemblies. 相似文献
27.
Flow goods (like electricity) are sold through auctions in a dynamic framework. An important design question is the frequency of such auctions. We use a simple dynamic auction model in continuous time to answer this question. We focus on the relationship between the persistency of bidders’ valuations and the optimal choice of frequency. If the seller focuses on the equilibrium in which bidders follow a repeated static Nash strategy, then the frequency of auctions should typically increase when persistency declines. However, accounting for the fact that bidders can follow different equilibria that are collusive in nature, the comparative statics are reversed, forcing the seller to reduce the frequency when bidders’ valuations are less persistent. The argument builds on the fact that high frequency auctions are more conducive to collusion among bidders. 相似文献
28.
S.F. Biagi M. Bourquin A.J. Britten R.M. Brown H. Burckhart A.A. Carter J.R. Carter Ch. Doré P. Extermann M. Gailloud C.N.P. Gee W.M. Gibson J.C. Gordon R.J. Gray P. Igo-Kemenes W.C. Louis T. Modis P. Mühlemann R. Weill 《Physics letters. [Part B]》1982,112(3):277-280
From a sample of 735 000 Ξ? decays, we have obtained a new upper limit for the branching ratio . The result is 1.9 × 10?5 at the 90% confidence level. 相似文献
29.
The elastic scattering, inelastic scattering, single-neutron transfer reactions 13C(17O, 16O) 14C, 13C(17O, 18O)12C and 13C(17O, 18O2+, 1.98)12C, and seven other exit channels which involve 7Li, 9Be, 11B and 15N have been measured for the system 17O+13C at 12.9 and 14 MeV c.m. It is shown that all reactions mentioned above have significant contributions from compound nuclear decay, following fusion of projectile and target. 相似文献
30.
J.P. Burq M. Chemarin M. Chevallier A.S. Denisov C. Doré T. Ekelöf J. Fay P. Grafström L. Gustafsson E. Hagberg B. Ille A.P. Kashchuk G.A. Korolev A.V. Kulikov S. Kullander M. Lambert J.P. Martin S. Maury A.A. Vorobyov 《Nuclear Physics B》1983,217(2):285-335
Differential cross sections for π?p and pp elastic scattering have been measured at incident momenta ranging from 30 to 345 GeV and in the t range 0.002 (GeV/c)2 ? |t| ? 0.04 (GeV/c)2. From the analysis of the data, the ratio ? (t = 0) of the real to the imaginary parts of the forward scattering amplitude was determined together with the logarithmic slope b of the diffraction cone.The results on the real parts confirm the validity of the forward dispersion relations at high energies. Using the dispersion relations, it was shown that the experimental data on ?π?p(t = 0) require a continuous rise of the total πp cross sections, at least up to the energy of 2000 GeV, thus revealing a close similarity in high-energy behaviour of πp and pp interactions.The results on the slope parameters from this experiment together with the analysis of the available world data demonstrate that the existing experimental data are consistent with the hypothesis of a universal shrinkage of the hadronic diffraction cone at high energies. The value of the asymptotic shrinkage parameter αp′ was found to be independent of the kind of the incident hadron and of the momentum transfer in the t range |t| ? 0.2 (GeV/c)2 : 2αp′ = ± 3 (GeV/c)?2. 相似文献