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951.
This paper investigates a method for predicting the generalization error that a multi-layer network of Sigma-pi units will, on average, exhibit. Theoretical values are compared with those obtained by the computer simulation of small networks learning parity and contiguity functions. 相似文献
952.
953.
Summary Recent progress in the modelling of exchanged Cu sites and their interactions with small molecules, based on DFT cluster calculations, is briefly reviewed. 相似文献
954.
955.
956.
S. Nourbakhsh W. H. Rhee O. Sahin H. Margolin 《Metallurgical and Materials Transactions A》1994,25(7):1501-1507
A series of single-crystal Al2O3-fiber-reinforced Ni3Al-based intermetallic matrix composites were fabricated by pressure casting. The matrices employed were
binary Ni3Al, Ni3Al-0.5 at. pct Cr, and Ni3Al-0.34 at. pct Zr. The development of microstructure upon oxidation in air at either 1100 °C or 1200 °C was investigated
by optical, scanning, and transmission electron microscopy. In air-oxidized binary Ni3Al, some of the fibers were fully or partially covered with a layer of oxide. A weak fiber/matrix bond in this system, which
led to fiber debonding during composite processing, is believed to be responsible for the ingress of O into the composite
and oxidation of the matrix in the debonded regions at the fiber/matrix interface. Addition of Cr to Ni3Al resulted in an almost threefold increase in fiber/matrix bond strength. No oxidation of the interface was observed. A thick
layer of oxide was formed around all the fibers when the composite was thermally cycled prior to isothermal annealing. Addition
of Zr to Ni3Al resulted in the formation of a layer of ZrO2 on the surface of the fibers during composite processing. The ZrO2 layer provided a fast path for the diffusion of O, which led to the formation of a rootlike oxide structure around the fibers.
The rootlike structure consisted of a network of Al2O3-covered ZrO2. 相似文献
957.
958.
Vogler W. 《Information and Computation》1995,121(2)
This paper is concerned with timing considerations for concurrent systems where the time needed by the individual actions is not known beforehand: it has long been suspected that the power of partial order semantics is needed here. We develop a suitable testing scenario to study this idea. With one view of timed behaviour, we can confirm that interval semiword semantics, a special partial order semantics, is indeed what can be observed with timed tests. With another view, our testing scenario leads to timed-refusal-trace semantics; this is a noninterleaving semantics, but it seems that it cannot be represented with partial orders in a meaningful way. 相似文献
959.
960.
Although memory disorders are frequently seen in survivors of brain injuries, remediation of patients with severe memory disorders is still relatively neglected in clinical practice due to pessimism by clinicians regarding the efficacy of such remediation. With respect to memory journal training, a further reason for this neglect is likely the lack of readily accessible protocols that therapists can use to work with these patients. The purpose of the present paper is to describe a new memory journal training protocol that was developed to teach brain injury survivors how to compensate for severe memory impairments by using three strengths of most brain injury survivors: immediate attention, procedural memory, and old learning. A training protocol is described that involves baseline testing and a needs assessment, five levels of training exercises, and discharge probe testing. It is concluded that patients with severely impaired memory abilities can learn the present system when care is taken to individualize journals, conduct proper needs assessments, and provide structured training exercises geared to the strengths of memory impaired persons. 相似文献