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61.
We answer two questions of Allouche and Shallit regarding k-regular sequences and k-context-free sequences. One of these has been solved independently in another way by Bell. We also provide a partial solution to another question of Allouche and Shallit regarding the subword complexity of k-context-free sequences. 相似文献
62.
Two years ago, the editors reasoned that the diverse and fundamental character of religious experience would promote an equally varied special issue devoted to the topic of psychotherapy and religion. We have not been disappointed. The papers composing this issue vary greatly in terms of literary style, research methodology, theoretical persuasion, and religious topics. There remains a need to clarify the extent to which religious issues or material that emerge during therapy need to be dealt with via "new" techniques (involving major modifications of classical techniques and ideologies) or via the classical methodologies, informed, perhaps, by expanded insights and perspectives. This issue is meant to be both current and historically representative. These two goals have not always been in agreement. The day of monolithic theories, presumed to address all matters of religious and psychotherapeutic importance, has passed, but not without leaving trails along which the present studies follow. Contemporary religious pluralism is more closely matched with the varied beliefs and problems of those seeking psychotherapy. This change has entailed a growing refinement in the psychological study of therapy and religious practice; it also implies a more astute and psychologically informed understanding of both the healthy and pathological aspects of religious experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
Moshe Sheintuch 《Chemical engineering science》2005,60(11):2991-2998
The analysis of a flow-reversal reactor, constructed from a catalytic bed imbedded within two inert beds and catalysing an instantaneous reaction, shows that the main parameters that determine the maximal reactor temperature are the thermodynamic parameters, heat loss through the walls and the conductivity and length of the inert zones. We show how these parameters can be easily extracted from the experimental data of very fast reactions, and demonstrate it for ethylene and for propane oxidation. We also derive an approximation for the maximal temperature for fast or slow reactions. These approximations are compared with experimental results obtained during propane (with low feed concentration) or methane oxidation. 相似文献
64.
In an attempt to develop a desirable resin formulation for spilled oil absorption, segmented polyurethanes of various types and lengths of hard and soft segments have been synthesized and tested for X‐ray diffraction, thermal, mechanical, and dynamic mechanical properties in addition to oil and water absorptions. Significant oil absorption was obtained with ether type polyol of high molecular weight, especially with short hard segments of long‐chain diamines. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2080–2087, 2005 相似文献
65.
66.
Field Tiffany; Healy Brian T.; Goldstein Sheri; Guthertz Moshe 《Canadian Metallurgical Quarterly》1990,26(1):7
Behavior-state matching and synchrony in interactions were assessed in 48 depressed and nondepressed mother–infant dyads when the infants were 3 months old. Attentive/affective behavior states were coded for the infants and mothers on a negative to positive scale. The depressed mothers and their infants matched negative behavior states more often and positive behavior states less often than did the nondepressed dyads. The total percentage of time spent in matching behavior states was less for the depressed than for the nondepressed dyads. Cross-spectral analyses of the mothers' and the infants' behavior-state time series suggested only a trend for greater coherence or synchrony in the interactions of the nondepressed dyads. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
We show that a moving-front solution in a cylindrical shell packed-bed catalyzing a first-order activated reaction may bifurcate into transversal patterns when PeC/PeT<ΔTad/ΔTm, i.e. when the ratio of the mass to heat Pe numbers is smaller than the ratio of the adiabatic to maximal temperature rises. This coincides with the previous condition of transversal patterns to emerge in stationary fronts [PeC/PeT<1 [Viswanathan, G., Bindal, A., Khinast, J., Luss, D., 2005. Stationary transversal hot zones in adiabatic packed-bed reactors. A.I.Ch.E. Journal 51, 3028-3038]] and extends the bifurcations condition to the case of moving fronts. The novel condition cannot be satisfied in a downstream propagating front (ΔTm/ΔTad>1), but for an upstream propagating front (toward the cold reactor inlet) ΔTm/ΔTad<1 and the symmetry breaking can be obtained within a feasible domain of operating conditions (PeC/PeT>1). It was also assumed that the axial and the transversal Pe numbers vary consistently, i.e. κC=PeC⊥/PeC=κT=PeT⊥/PeT. A similar condition was also obtained using a simplified model composed of two 1-D beds with heat and mass exchange between them.Bifurcation diagram showing domains of transversal patterns is constructed using a learning two-bed model. These predictions are verified by direct numerical simulations of the continuous 2-D cylindrical shell model showing various types of moving transversal patterns within a feasible domain of the state parameters with PeC>PeT. In the case of varying ratio (κC≠κT) the pattern domain can be significantly extended toward larger PeC/PeT. 相似文献
68.
We present a simple distributed algorithm that resolves store-and-forward deadlocks in data communication networks. The basic idea of the algorithm is to detect cycles of nodes that may cause store-and-forward deadlocks, and to rotate packets along these cycles. The algorithm uses a fixed amount of storage in each node for its execution, and, under reasonable assumptions upon the routing and packet handling, it ensures that packets that enter the network arrive at their destinations in finite time.Part of this work was done while this author was on sabbatical leave with IBM, Thomas J. Watson Research Center, Yorktown Heights, NY 10598, USA. 相似文献
69.
This article includes four experiments in which four criteria for testing the automaticity of coding of temporal order information are examined. Results show that memory for temporal order information is affected by intention to learn, competing task loads, encoding strategy, and subjects' age. The results, which generally hold for memory for absolute, as well as for relative temporal order information, do clarify the somewhat mixed pattern of results in previous studies, which was due, at least in part, to inappropriate testing methodologies. Such results, which are similar to recent tests of automaticity of frequency of occurrence and spatial location information, are at odds with the claim made by several researchers that memory for temporal order information is exclusively mediated by automatic processes. The concept of automaticity and the appropriateness of the testing criteria for it are discussed in light of the current results. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
Moshe Favelukis 《Chemical engineering science》2010,65(12):3808-3813
Steady and unsteady mass transfer in the continuous phase around slightly deformed oblate spheroidal drops at low (but not zero) Reynolds numbers was investigated theoretically. Asymptotic analytical solutions for short and long times, at large Peclet numbers, were obtained by the useful equations derived by Lochiel and Calderbank and by Favelukis and Mudunuri for axisymmetric drops of revolution, with the only requirements being the shape of the drop and the tangential velocity at the surface of the drop. As expected, the result, although complicated, represents a small correction to the classical problem of mass transfer around a spherical drop under creeping flow conditions, since the physical problem presented here requires both the Reynolds and the Weber number to be much smaller than one. 相似文献