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41.
Tuomo Valkonen 《Numerical Functional Analysis & Optimization》2013,34(7-8):931-952
We consider a generalization of the Weiszfeld algorithm with successive overrelaxation for data sets where some data point fields may be missing and prove its global convergence. A counterexample is also provided to the convergence of an alternative generalization. 相似文献
42.
Merja R. Häkkinen Tuomo A. Keinänen Seppo Auriola Leena Alhonen Jouko Vepsäläinen 《Tetrahedron》2009,65(2):547-5748
Novel di-, tetra- and octadeuterated derivatives of mono-N-alkylated diaminopropanes, spermidines, spermines, symmetrically bis-N-alkylated spermines and unsymmetrically bis-N-alkylated spermines were synthesized. Deuterium labels were introduced into the RHNCH2CH2CN intermediate either by exchanging the protons next to the nitrile group under basic conditions with D2O-EtOD mixture or/and by reducing the nitrile group to a CD2-NH2 fragment with LiAlD4. 相似文献
43.
Salla-Maarit Kokkonen Juha Nikkinen Jukka Remes Jussi Kantola Tuomo Starck Marianne Haapea Juho Tuominen Osmo Tervonen Vesa Kiviniemi 《Magnetic resonance imaging》2009
Analysis of resting-state functional magnetic resonance imaging (fMRI) data is based on detecting low-frequency signal fluctuations in functionally connected brain areas. These synchronous fluctuations in resting-state networks have been observed in several studies with healthy subjects. In this study, we explored if independent component analysis (ICA) can be used to localize the sensorimotor area from resting-state fMRI data in patients with brain tumors. Finger-tapping activation task and resting-state blood-oxygenation-level-dependent fMRI data were acquired from 8 patients with brain tumors and 10 healthy volunteers. Sensorimotor task independent components (ICtask) were used to verify resting-state independent components (ICrest) individually. In addition, sensorimotor ICrests were compared between the groups and no significant differences were detected in volume, spatial correlation or temporal correlation. These results show that it is possible to localize a sensorimotor area from resting-state data using ICA in patients with brain tumors. This offers a complementary method for assessing the sensorimotor area in subjects with brain tumors who have difficulties in performing motor paradigms. 相似文献
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Designs, Codes and Cryptography - In this article, we study locating-dominating codes in binary Hamming spaces $$\mathbb {F}^n$$ . Locating-dominating codes have been widely studied since their... 相似文献
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We prove a class of endpoint pointwise estimates for solutions to quasilinear, possibly degenerate elliptic equations in terms of linear and nonlinear potentials of Wolff type of the source term. Such estimates allow to bound size and oscillations of solutions and their gradients pointwise, and entail in a unified approach virtually all kinds of regularity properties in terms of the given datum and regularity of coefficients. In particular, local estimates in Hölder, Lipschitz, Morrey and fractional spaces, as well as Calderón–Zygmund estimates, follow as a corollary in a unified way. Moreover, estimates for fractional derivatives of solutions by mean of suitable linear and nonlinear potentials are also implied. The classical Wolff potential estimate by Kilpeläinen & Malý and Trudinger & Wang as well as recent Wolff gradient bounds for solutions to quasilinear equations embed in such a class as endpoint cases. 相似文献
49.
Huttunen KH Keränen HI Pääkkönen RJ Päivikki Eskelinen-Rönkä R Leino TK 《The Journal of the Acoustical Society of America》2011,129(3):1580-1593
It was explored how three types of intensive cognitive load typical of military aviation (load on situation awareness, information processing, or decision-making) affect speech. The utterances of 13 male military pilots were recorded during simulated combat flights. Articulation rate was calculated from the speech samples, and the first formant (F1) and second formant (F2) were tracked from first-syllable short vowels in pre-defined phoneme environments. Articulation rate was found to correlate negatively (albeit with low coefficients) with loads on situation awareness and decision-making but not with changes in F1 or F2. Changes were seen in the spectrum of the vowels: mean F1 of front vowels usually increased and their mean F2 decreased as a function of cognitive load, and both F1 and F2 of back vowels increased. The strongest associations were seen between the three types of cognitive load and F1 and F2 changes in back vowels. Because fluent and clear radio speech communication is vital to safety in aviation and temporal and spectral changes may affect speech intelligibility, careful use of standard aviation phraseology and training in the production of clear speech during a high level of cognitive load are important measures that diminish the probability of possible misunderstandings. 相似文献
50.
Paolo Baroni Tuomo Kuusi José Miguel Urbano 《Archive for Rational Mechanics and Analysis》2014,214(2):545-573
We derive the quantitative modulus of continuity $$\omega(r)=\left[ p+\ln \left( \frac{r_0}{r}\right)\right]^{-\alpha (n, p)},$$ which we conjecture to be optimal for solutions of the p-degenerate two-phase Stefan problem. Even in the classical case p = 2, this represents a twofold improvement with respect to the early 1980’s state-of-the-art results by Caffarelli– Evans (Arch Rational Mech Anal 81(3):199–220, 1983) and DiBenedetto (Ann Mat Pura Appl 103(4):131–176, 1982), in the sense that we discard one logarithm iteration and obtain an explicit value for the exponent α(n, p). 相似文献