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131.
Hannu Salonen 《International Journal of Game Theory》2010,39(3):351-357
We study the existence of Nash equilibria in games with an infinite number of players. We show that there exists a Nash equilibrium
in mixed strategies in all normal form games such that pure strategy sets are compact metric spaces and utility functions
are continuous. The player set can be any nonempty set. 相似文献
132.
Pauliina Ilmonen Jaakko Nevalainen Hannu Oja 《Statistics & probability letters》2010,80(23-24):1844-1853
We consider a semiparametric multivariate location–scatter model where the standardized random vector of the model is fixed using simultaneously two location vectors and two scatter matrices. The approach using location and scatter functionals based on the first four moments serves as our main example. The four functionals yield in a natural way the corresponding skewness, kurtosis and unmixing matrix functionals. Affine transformation based on the unmixing matrix transforms the variable to an invariant coordinate system. The limiting properties of the skewness, kurtosis, and unmixing matrix estimates are derived under general conditions. We discuss related statistical inference problems, the role of the sample statistics in testing for normality and ellipticity, and connections to invariant coordinate selection and independent component analysis. 相似文献
133.
Hannu Teisala Mikko Tuominen Mikko Aromaa Milena Stepien Jyrki M. Mäkelä Jarkko J. Saarinen Martti Toivakka Jurkka Kuusipalo 《Colloid and polymer science》2013,291(2):447-455
Surface wetting is an important and relevant phenomenon in several different fields. Scientists have introduced a large number of applications where special surface wetting could be exploited. Here, we study wetting phenomena on high- and low-adhesive superhydrophobic liquid flame spray (LFS)-generated TiO2 coatings on paper and pigment-coated board substrates using water–ethanol solution as a probe liquid. Submicrometer-scale air gaps, which exist on superhydrophobic surfaces below the liquid droplets, were more stable with the ethanol increment than the larger-scale micrometric air gaps. With the droplet ethanol concentration of 15 wt%, static contact angle as high as 155?±?2° was measured on the LFS–TiO2-coated board. Transition from the low-adhesive wetting state to the high-adhesive state was demonstrated on the LFS–TiO2-coated paper. The LFS method enables efficient roll-to-roll production of surfaces with special wetting properties on economically viable board and paper substrate materials. 相似文献
134.
A violation of the polarization selection rules for Raman scattering is observed in porous silicon. This effect is caused
by a weak disorientation of the quasi-one-dimensional silicon wires, with the crystal structure of the wires themselves and
the macroscopic homogeneity of the material in optical experiments remaining intact.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 2, 95–100 (25 January 1998) 相似文献
135.
136.
Controlled grafting of acetylated starch by atom transfer radical polymerization of MMA 总被引:1,自引:0,他引:1
Graft copolymers of acetylated starch oligomer (AS) and poly(methyl methacrylate) (PMMA) were polymerized by atom transfer radical polymerization (ATRP). AS was converted to an ATRP macroinitiator by converting a part of the hydroxyl groups of AS to 2-bromoisobutyryl groups. Macroinitiators with varying degrees of substitution for the 2-bromoisobutyryl group were prepared. The polymerizations were conducted using CuBr/BiPy catalyst system, either in bulk or in 1:1 v/v THF solution. They proceeded with first-order kinetics and the molecular weights of the polymers increased linearly with conversion. Graft copolymers with different graft densities and graft lengths were prepared in a controlled manner. The hydrophobicity of these copolymers was studied by contact angle measurements. 相似文献
137.
Hanif Ullah Munair Badshah Ermei Mäkilä Jarno Salonen Mohammad-Ali Shahbazi Hélder A. Santos Taous Khan 《Cellulose (London, England)》2017,24(3):1445-1454
Bacterial cellulose (BC) was investigated for the first time for the preparation of capsule shells for immediate and sustained release of drugs. The prepared capsule shells were characterized using X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectroscopy. The BC capsule shells were studied for drug release using an USP type-I dissolution apparatus. Irrespective of the drying method and the thickness of the BC sheet, the capsule shells displayed an immediate drug release profile. Moreover, the addition of release-retardant cellulosic polymers sustained the drug release having first-order kinetics for hydroxypropylmethylcellulose and carboxymethyl cellulose sodium with R 2 values of 0.9995 and 0.9954, respectively. Furthermore, these capsules shells remained buoyant in 0.1 N HCl (pH 1.2) solution up to 12 h. This study showed that BC is a promising alternative to gelatin capsules with both immediate and sustained drug release properties depending upon the compositions of the encapsulated materials. 相似文献
138.
139.
H Pulakka L Laaksonen S Yrttiaho V Myllylä P Alku 《The Journal of the Acoustical Society of America》2012,132(2):848-861
Artificial bandwidth extension methods have been developed to improve the quality and intelligibility of narrowband telephone speech and to reduce the difference with wideband speech. Such methods have commonly been evaluated with objective measures or subjective listening-only tests, but conversational evaluations have been rare. This article presents a conversational evaluation of two methods for the artificial bandwidth extension of telephone speech. Bandwidth-extended narrowband speech is compared with narrowband and wideband speech in a test setting including a simulated telephone connection, realistic conversation tasks, and various background noise conditions. The responses of the subjects indicate that speech processed with one of the methods is preferred to narrowband speech in noise, but wideband speech is superior to both narrowband and bandwidth-extended speech. Bandwidth extension was found to be beneficial for telephone conversation in noisy listening conditions. 相似文献
140.
Dr. Jan Dreiser Kasper S. Pedersen Dr. Alexander Schnegg Dr. Karsten Holldack Joscha Nehrkorn Marc Sigrist Dr. Hannu Mutka Dr. Høgni Weihe Dr. Vladimir S. Mironov Prof. Jesper Bendix Prof. Oliver Waldmann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(11):3693-3701
We have investigated the single‐molecule magnets [MnIII2(5‐Brsalen)2(MeOH)2MIII(CN)6]NEt4 (M=Os ( 1 ) and Ru ( 2 ); 5‐Brsalen=N,N′‐ethylenebis(5‐bromosalicylidene)iminate) by frequency‐domain Fourier‐transform terahertz electron paramagnetic resonance (THz‐EPR), inelastic neutron scattering, and superconducting quantum interference device (SQUID) magnetometry. The combination of all three techniques allows for the unambiguous experimental determination of the three‐axis anisotropic magnetic exchange coupling between MnIII and RuIII or OsIII ions, respectively. Analysis by means of a spin‐Hamiltonian parameterization yields excellent agreement with all experimental data. Furthermore, analytical calculations show that the observed exchange anisotropy is due to the bent geometry encountered in both 1 and 2 , whereas a linear geometry would lead to an Ising‐type exchange coupling. 相似文献