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991.
992.
Mature radula pieces from the chitonAcanthopleura hirtosa were studied using Mössbauer spectroscopy. The magnetite present in the radulae was found to have a distribution of Verwey transition temperatures in the range 85–100K. It was deduced that the magnetite was non-stoichiometric with an average formula Fe2.98O3. About 10% of the Fe in the radulae was in the form of maghemite and about 19% was in the form of paramagnetic or superparamagnetic phases. 相似文献
993.
There are two main classes of iterative methods in nondifferentiable optimization (NDO). In thebasic NDO, the information is limited to the objective function and at least one element of its subdifferential, while in thecomposite NDO, the objective function is split into a sum of a smooth and a nonsmooth function. Our work unifies these two approaches for benefiting of their respective advantages. 相似文献
994.
Dominique Delbourg Gérard Penillault Tran Khan Tuong Martial Decourt Nicole Borome Henri Harroch Bertrand Lessellier Bernard Waast Jean Pierre Mouffron 《Pramana》2002,59(6):1025-1033
A new control system was designed for the tandem MP-9 at Orsay. Because of the existing devices located on high voltage platforms
and the lack of space inside the accelerator, in-house electronic cards based on micro-controllers and an optical fieldbus
were developed to collect data. VME processors under VxWorks, a real time operating system, manage the fieldbus, concentrate
the accelerator information and transmit it to the supervisory software through the ethernet network. This software consists
of a collection of Java virtual machines (JVM) running on several Unix work-stations and PCs under Windows. Some of the Java
virtual machines manage apparatus, instruments, local display and connections to an object database and VME concentrators.
Other manage general synoptics. JVMs communicate between themselves with RMI protocol and JRPC with VME concentrators. So
the supervisory software can be spread over several control stations throughout the network. 相似文献
995.
Recent results on the memory storage capacity of the outer-product algorithm indicate that the algorithm stores of the order of n/log n memories in a network of n fully interconnected linear threshold elements when it is required that each memory be exactly recovered from a probe which is close enough to it. In this paper a rigourous analysis is presented of generalizations of the outer-product algorithm to higher-order networks of densely interconnected polynomial thresh-old units of degree d. Precise notions of memory storage capacity are formulated, and it is demonstrated that both static and dynamic storage capacities of all variants of the outer-product algorithm of degree d are of the order of nd/log n. 相似文献
996.
P. Gippner K. D. Schilling W. Seidel F. Stary E. Will H. Sodan S. M. Lukyanov V. S. Salamatin Yu. E. Penionzhkevich G. G. Chubarian R. Schmidt 《Zeitschrift für Physik A Hadrons and Nuclei》1986,325(3):335-346
Fragment mass distributions are presented obtained in the heavy-ion reactions22Ne+249Cf,32S+238U,40Ar+232Th and56Fe+208Pb leading to composite systems with equal nuclear charge numberZ=108. The experiments were performed at the heavy-ion cyclotron U 300 of the Laboratory of Nuclear Reactions in Dubna. The spectrometer DEMAS was used to measure the time-of-flight values and the laboratory angles of the correlated fragments. The shape of the mass distributions strongly depends on the initial mass asymmetry. When decreasing the bombarding energy down to values near the Coulomb barrier, the mass distributions obtained in the reactions32S+238U and40Ar+232Th exhibit relative maxima ofM≈205 interpreted to be due to stabilizing effects of nuclear shells during the fragmentation process. 相似文献
997.
998.
Anton Bovier Véronique Gayrard Pierre Picco 《Probability Theory and Related Fields》1995,101(4):511-546
Summary We study the Kac version of the Hopfield model and prove a Lebowitz-Penrose theorem for the distribution of the overlap parameters. At the same time, we prove a large deviation principle for the standard Hopfield model with infinitely many patterns.Work partially supported by the Commission of the European Communities under contract No. SC1-CT91-0695 相似文献
999.
1000.
Given a compact metric space X and a continuous map f from X to itself, we construct a barrier function for chain-recurrence. We use it to endow the space of chain-transitive components with a non-trivial ultrametric distance and to construct Lyapunov functions for f. Most of these constructions are then generalized on an arbitrary separable metric space to a continuous compactum-valued map. 相似文献