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101.
In this paper, we propose two updated data dissemination methods to not only reduce the number of accesses to old replicas, but also to improve the data accessibility in ad hoc networks where data items are updated regularly. In the first method, when a mobile host updates a data item, it disseminates the updated data item after the flooding of with invalidation reports. In the second method, two newly connected mobile hosts disseminate updated data items with each other after the flooding with invalidation reports. 相似文献
102.
A numerical analysis technique that incorporates Voronkov's model were examined and used to estimate the distribution of defects during crystal growth. By comparisons of the distribution of the density of LSTD and the position of R-OSF in non-nitrogen-doped (non-N-doped) and nitrogen-doped (N-doped) silicon crystals, it is found that the results of the numerical analyses agree with practically evaluated data. The observations suggest that the R-OSF nucleus is a VO2 complex that is formed by bonds between oxygen atoms and residual vacancies consumed during the formation of void defects. This suggests that Voronkov's model can be used to accurately predict the generation and growth of defects in silicon crystals. This numerical analysis technique was also found to be an effective method of estimating the distribution of defects in silicon crystals during crystal growth. 相似文献
103.
We give a general category theoretic formulation of the substitution structure underlying the category theoretic study of
variable binding proposed by Fiore, Plotkin, and Turi. This general formulation provides the foundation for their work on
variable binding, as well as Tanaka’s linear variable binding and variable binding for other binders and for mixtures of binders
as for instance in the Logic of Bunched Implications. The key structure developed by Fiore et al. was a substitution monoidal
structure, from which their formulation of binding was derived; so we give an abstract formulation of a substitution monoidal
structure, then, at that level of generality, derive the various category theoretic structures they considered. The central
construction we use is that of a pseudo-distributive law between 2-monads on Cat, which suffices to induce a pseudo-monad on Cat, and hence a substitution monoidal structure on the free object on 1. We routinely generalise that construction to account
for types.
This work has been done with the support of EPSRC grant GR/586372/01, A Theory of Effects for Programming Languages. 相似文献
104.
Properties of graphite prepared from boron-doped pitch as an anode for a rechargeable Li ion battery
Boron-doped graphites were derived from a naphthalene-based pitch mixed with para-xylene glycol (PXG) or dimethyl para-xylene glycol (DMPXG) as a cross-linking agent and three types of boron-containing compounds as a graphitization catalyst, and their anode performances were investigated. The structural analysis of the obtained graphites revealed that PXG functioned mainly as a two-dimensional cross-linking agent during the heat treatment process and DMPXG functioned partially as a three-dimensional. The average interlayer spacing decreased and lattice constant, a0, and graphitizability increased with increasing the amount of boron atoms added. The result indicated that the carbon atoms were replaced by boron atoms. The anode performance was improved by the enhancement of graphitizability. The structural parameters and anode performance of boron-doped graphites did not depend on the kind of boron-containing compounds but the amount of boron atoms added in pitch and the kind of cross-linking agent. 相似文献
105.
Catastrophic stress induced by Hanshin-Awaji earthquake seems to promote rheological deterioration associated with high blood pressure, increased blood viscosity due to hemoconcentration and increased fibrinogen level. These changes lead to prolonged endothelial cell dysfunction demonstrating high levels of von Willebrand factor, tissue type plasminogen activator and plasmin.alpha 2 plasmin inhibitor complex, and accelerate fibrin turnover as the result of a high D-dimer level from the post earthquake period until 4-6 months later. There were remarkable changes in biochemical parameters except for uric acid, BUN, triglyceride level. An increase in these acute changes caused by mental and physical stress might trigger obstructive thrombus in coronary arteries in the elderly after an earthquake. In conclusion, earthquake induced stress could be considered a transient cardiovascular risk factor. 相似文献
106.
SL Neuhausen J Swensen Y Miki Q Liu S Tavtigian D Shattuck-Eidens A Kamb MR Hobbs J Gingrich H Shizuya 《Canadian Metallurgical Quarterly》1994,3(11):1919-1926
BRCA1, a breast and ovarian cancer susceptibility locus, has been isolated and maps to 17q21. A physical map of the BRCA1 region which extended from the proximal boundary at D17S776 to the distal boundary at D17S78 was constructed and consists of 51 sequence tagged sites (STSs) from P1 and YAC ends, nine new short-tandem repeat (STR) polymorphic markers, and eight identified genes. The contig, which spans the estimated 2.3 Mb region, contains 29 P1s, 11 YACs, two BACs, and one cosmid. Based on key recombinants in two linked families, BRCA1 was further localized to a region bounded by D17S1321 on the proximal side and D17S1325 on the distal side. Within this estimated 600 kb region, the contig was composed completely of P1s and BACs ordered by STS-content mapping and confirmed by DNA restriction fragment fingerprinting. 相似文献
107.
A new sequential image processing method for motion compensation of a moving object with stringy shape has been developed for estimating the pharyngeal pulsation of the nematode Caenorhabditis elegans under several environmental conditions. The method is based on the pixel data transfer on a new image frame while changing the boundary shape and the position but preserving the conformation of the inner structure of an object. All digitized image frames of C. elegans were first converted to motion-compensated images to arrange the pulsation site in the same region of the every transformed frame. The pulsation site was then automatically detected by determining the pixels where the temporal brightness variation was much larger than that of the other pixels. Finally, the pulsation frequency was determined by the Fourier analysis. The validity of our method has been confirmed by analyzing various test data, and the method has been applied for detecting the pharyngeal pulsation frequencies of C. elegans on some environmental conditions, i.e. feed bacteria-free/rich, doping of nerve inactivating ethyl-alcohol and nerve stimulant neurochemical substance of serotonin. The motion compensation method automatically provided reasonable pulsation frequencies which were found to be comparable to those obtained by manual counting. Thus the method is useful for systematic investigations on the variation of pharyngeal pulsation associated with the activity change of the nervous system in environments. 相似文献
108.
Xixian Chen Suzuki M. Miki N. Nagai N. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1995,41(5):1409-1417
To reduce the system initialization time in high-speed full-duplex data transmission over two-wire lines, we propose an efficient full-duplex fast training algorithm which can simultaneously estimate the impulse responses of echo paths and channels at both ends. Two mutually orthogonal periodic sequences are designed and used to co-estimate the near echo, the far echo with bulk delay, and the channel response. The new algorithm can reduce the tap-setting time to half of that required by the traditional half-duplex fast training schemes. The effects of channel noise and symbol rate offset between two ends are examined in terms of both mean-square error (MSE) and signal-to-noise ratio (SNR). Both the theoretical analysis and computer simulation show that there are three degrading factors due to symbol rate offset. The SNR is inversely proportional to the sum of the estimated coefficients, the half period of the training sequences, and the square of symbol rate offset. If the far-signal-to-channel-noise ratio is 30 dB, then the degradation is significant when the symbol rate offset is more than 10 -4. If it is 40 dB, then the degradation is significant when the symbol rate offset is above 3×10-5 相似文献
109.
110.