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71.
Juichiro Arai Katsuhiro Kojima Nobuhide Mori 《Journal of Low Temperature Physics》1996,105(3-4):455-460
Fe3+-ESR measurements are carried out for the samples of (La1–xSrx)2Cu1–yFeyO4–z. Peak-peak width Hpp of the signals decreases with falling temperature until minimum value and rises sharply with further decreasing temperature, which is approximated by Hpp = C0 +C1/T + BT. The Hpp behavior at high temperature and at low temperature can be analyzed by Korringa mechanism and slowing down of Fe3+ spin fluctuation, respectively. From the analysis of coefficient B's of Korringa terms, C0 and g-shift, it is revealed that the magnetic interaction of Fe3+ with hole carriers and Ce2+ spins depends strongly on hole density. 相似文献
72.
Hiroki Yamaguchi Tsuneo Hanawa Oto Yamamoto Yu Matsuda Yasuhiro Egami Tomohide Niimi 《Microfluidics and nanofluidics》2011,11(1):57-64
The tangential momentum accommodation coefficient (TMAC) was investigated experimentally from the mass flow rate through a
single microtube under the slip flow and the early part of the transition regime. The measurements were carried out by the
constant-volume method under the mean Knudsen number smaller than 0.3, which is based on the mean pressure of the inlet and
the outlet of the microtube, to apply the second-order slip boundary condition. To measure TMACs on various materials, quite
large microtube was employed, which require the reduction in leakage. TMAC was obtained from the slip coefficient determined
by the relation of the mass flow rate to the mean Knudsen number. The obtained mass flow rate was well explained by the theoretical
equation. TMACs of deactivated-fused silica with argon, nitrogen, and oxygen were measured, showing the tangential momentum
was not accommodated completely to the surface, and the values showed good agreement with previous studies. From the comparison
between microtubes with different inner diameter, it is showed that TMAC is determined mainly by gas species and surface material. 相似文献
73.
Hidenori Okuzaki Kosuke Hosaka Hiroki Suzuki Takamichi Ito 《Sensors and actuators. A, Physical》2010,157(1):96-99
Temperature dependence of water vapor sorption and electro-active polymer actuating behavior of free-standing films made of poly(3,4-ethylenedioxythiophene) doped with poly(4-styrenesulfonate) (PEDOT/PSS) was investigated by means of sorption isotherm and electromechanical analyses. The non-porous PEDOT/PSS film, having a specific surface area of 0.13 m2 g?1, sorbed water vapor of 1080 cm3(STP) g?1, corresponding to 87 wt%, at relative water vapor pressure of 0.95. A temperature rise from 25 °C to 40 °C lowered sorption degree, indicative of an exothermic process, where isosteric heat of sorption decreased with increasing water vapor sorption and the value reached 43.9 kJ mol?1, being consistent with the heat of water condensation (44 kJ mol?1). Upon application of 10 V, the film underwent contraction of 2.46% at 5 °C caused by desorption of water vapor due to Joule heating, which slightly decreased to 2.10% at 45 °C. The speed of contraction was one order of magnitude faster than that of expansion and less dependent on the temperature since water vapor sorbed in the film were forced to desorb by Joule heating. In contrast, the higher the temperature the faster the film expansion because diffusion coefficient increased as the temperature became higher. 相似文献
74.
75.
Caio César Mori Carélo Ives Renê Venturini Pola Ricardo Rodrigues Ciferri Agma Juci Machado Traina Caetano Traina Jr Cristina Dutra de Aguiar Ciferri 《Information Systems》2011
Searching in a dataset for elements that are similar to a given query element is a core problem in applications that manage complex data, and has been aided by metric access methods (MAMs). A growing number of applications require indices that must be built faster and repeatedly, also providing faster response for similarity queries. The increase in the main memory capacity and its lowering costs also motivate using memory-based MAMs. In this paper, we propose the Onion-tree, a new and robust dynamic memory-based MAM that slices the metric space into disjoint subspaces to provide quick indexing of complex data. It introduces three major characteristics: (i) a partitioning method that controls the number of disjoint subspaces generated at each node; (ii) a replacement technique that can change the leaf node pivots in insertion operations; and (iii) range and k-NN extended query algorithms to support the new partitioning method, including a new visit order of the subspaces in k-NN queries. Performance tests with both real-world and synthetic datasets showed that the Onion-tree is very compact. Comparisons of the Onion-tree with the MM-tree and a memory-based version of the Slim-tree showed that the Onion-tree was always faster to build the index. The experiments also showed that the Onion-tree significantly improved range and k-NN query processing performance and was the most efficient MAM, followed by the MM-tree, which in turn outperformed the Slim-tree in almost all the tests. 相似文献
76.
The minimum number of NOT gates in a Boolean circuit computing a Boolean function f is called the inversion complexity of f. In 1958, Markov determined the inversion complexity of every Boolean function and, in particular, proved that log2(n+1) NOT gates are sufficient to compute any Boolean function on n variables. In this paper, we consider circuits computing non-deterministically and determine the inversion complexity of every Boolean function. In particular, we prove that one NOT gate is sufficient to compute any Boolean function in non-deterministic circuits if we can use an arbitrary number of guess inputs. 相似文献
77.
Keiji Hayashi Tomoki Shiraishi Kazuho Toyoda Fumiya Tanaka Taiga Mori Takumi Hata 《Computer Physics Communications》2011,(9):2032-2035
Laws of dynamic nano-friction (i.e., continuous wearless friction) were searched for under steady spatial distributions of the local quasi-temperature, by molecular dynamics (MD) simulations. The temperature control of the non-conservative model was carried out by extending the isothermal MD method using the Nosé–Poincaré thermostat. The results suggested that the threshold phenomenon characterizes sliding-velocity dependence of the nano-frictional force between crystal lattices constituting a nano-electromechanical system (NEMS). This phenomenon was turned out to be a universal feature, whether heat transfer to the environment exists or not. 相似文献
78.
T. Iwashita K. Yosui M. Mori E. Kobayashi S. Abe 《Computing and Visualization in Science》2008,11(3):123-128
A multi-grid method is one of the most powerful linear solvers for finite element electromagnetic field analysis. However,
as the discretized model has recently been enlarged, a solution process for a linear system arising on the coarsest level
tends to be problematic in a complete multi-grid solution process. Whereas a linear system on the coarsest level is generally
solved by a direct solver, we solve it here by means of an iterative solver to reduce the memory requirements. Since a conventional
preconditioning technique is not effective for such a linear system, we introduce preconditioning techniques based on Arnold,
Falk, and Winther’s and on Hiptmair’s smoothers. Numerical tests show that the newly installed preconditioning technique greatly
improves the convergence rate. 相似文献
79.
Yamamoto T Kato R Yamamoto HM Fukaya A Yamasawa K Takahashi I Akutsu H Akutsu-Sato A Day P 《The Review of scientific instruments》2007,78(8):083906
We have developed a technique for the anisotropic extension of fragile molecular crystals. The pressure medium and the instrument, which extends the pressure medium, are both made from epoxy resin. Since the thermal contraction of our instrument is identical to that of the pressure medium, the strain applied to the pressure medium has no temperature dependence down to 2 K. Therefore, the degree of extension applied to the single crystal at low temperatures is uniquely determined from the degree of extension in the pressure medium and thermal contractions of the epoxy resin and the single crystal at ambient pressure. Using this novel instrument, we have measured the temperature dependence of the electrical resistance of metallic, superconducting, and insulating materials. The experimental results are discussed from the viewpoint of the extension (compression) of the lattice constants along the parallel (perpendicular) direction. 相似文献
80.
Report on highly automated works in Japan — management of labour in line with technology development
In recent years drastic shifts in the paradigms of politics, economics and technologies have occurred throughout the world. The shifts in these three fields are all related. It is our responsibility to investigate these shifts from the aspects of society and mankind for the prosperity of future generations. For this, societies should share with each other their wisdom and knowledge in an effort to plan for the future.Presented at conference on Ecology of Science and Technology, Japan Science Foundation, Tokyo, 1992. 相似文献