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51.
This paper describes approaches for machine learning of context free grammars (CFGs) from positive and negative sample strings, which are implemented in Synapse system. The grammatical inference consists of a rule generation by “inductive CYK algorithm,” mechanisms for incremental learning, and search. Inductive CYK algorithm generates minimum production rules required for parsing positive samples, when the bottom-up parsing by CYK algorithm does not succeed. The incremental learning is used not only for synthesizing grammars by giving the system positive strings in the order of their length but also for learning grammars from other similar grammars. Synapse can synthesize fundamental ambiguous and unambiguous CFGs including nontrivial grammars such as the set of strings not of the form ww with w∈{a,b}+.  相似文献   
52.
This study realizes belief/reliability change of a judge in a legal judgment by dynamic epistemic logic (DEL). A key feature of DEL is that possibilities in an agent’s belief can be represented by a Kripke model. This study addresses two difficulties in applying DEL to a legal case. First, since there are several methods for constructing a Kripke model, our question is how we can construct the model from a legal case. Second, since this study employs several dynamic operators, our question is how we can decide which operators are to be applied for belief/reliability change of a judge. In order to solve these difficulties, we have implemented a computer system which provides two functions. First, the system can generate a Kripke model from a legal case. Second, the system provides an inconsistency solving algorithm which can automatically perform several operations in order to reduce the effort needed to decide which operators are to be applied. By our implementation, the above questions can be adequately solved. With our analysis method, six legal cases are analyzed to demonstrate our implementation.  相似文献   
53.
The dynamical susceptibility of the B phase of superfluid He-3 in the presence of dipolar coupling is calculated in the collisionless regime. Two poles of the susceptibility that correspond to the spin wave and the mode with energy gap (2/5)1/2 2 are found. The result agrees with that of Tewordt and Einzel qualitatively and contradicts the recent work by Maki. The residue of the high-frequency mode becomes remarkable near the transition temperature. The dispersion relations of these modes atT=0 K and near the transition temperature are given in the most general form.  相似文献   
54.
The shear viscosity (T) in the Balian-Werthamer (BW) state of superfluid 3 He is calculated variationally throughout the region 0t 1(t=T/T c) from the transport equation for Bogoliubov quasiparticles. Coherence factors are treated exactly in the calculation of the collision integral. The numerical result for =s= s(T)/n(Tc) agree very well with experiment in the range 0.8t1.0. Analytic expressions = 0.577 (1–1.0008t) and =1–(23/64) [=(T)/k B T] are obtained in the low-temperature region and in the vicinity ofT c, respectively. From the numerical analysis it is shown that the latter equation is valid only in the temperature range 0.9997t1.0.Supported by the Research Institute for Fundamental Physics, Kyoto University.  相似文献   
55.
The morphological characteristics, chromium valence state, and cation transport in the vicinity of grain boundary in La1-xCaxCrO3 were investigated by using TEM/EDS, XPS and SIMS techniques. The width of grain boundary was around 1 nm where anomalous enrichment of calcium was observed. Higher valence state of chromium such as Cr6+(d0) was detected in the grain boundaries whereas Cr3+(d3) and Cr4+(d2) were dominant in the bulk. Very fast interdiffusion of alkaline earths was observed in the Sr2+-La0.75Ca0.25CrO3 system. All observed phenomena were correlated by assuming the A-site vacancy which may be induced by the formation of Cr6+ at grain boundaries.  相似文献   
56.
57.
The nonlinear response and failure mechanism of reinforced concrete frame-wall systems is investigated through the employment of a mathematical model. The mathematical model is composed of two mechanical models: a concentrated spring model used for the flexural behaviour of beam and column type members and a multiple spring model used for the response of the wall system. Both account for inelastic behaviour of reinforced concrete.The mathematical model is applied to a ten-storey frame-wall system. The constituent members are replaced by one of the mechanical models whose stiffness characteristics reflect the inelastic properties and hysteresis tendencies of the member. The resulting equations are solved by a step by step time integration procedure. Computed results are compared with experimental results obtained from a structure tested on the Illinois earthquake simulator. The correlated results are then used to define the significant response characteristics.  相似文献   
58.
Journal of Inorganic and Organometallic Polymers and Materials -  相似文献   
59.
Emulsifier-free emulsion polymerization of styrene in acetone–water medium was carried out using potassium persulfate as initiator. Below acetone content of 40 vol %, stable emulsion was prepared and polymerizations were remarkably fast compared with those in pure water. The particle size decreased from 0.5 to 0.17 μm with an increase in acetone content in the range 0–40 vol %, and the distributions were very sharp. The optimum polymerization for the preparation of the stable emulsion was: styrene, 20 vol %; acetone/water, 40/60 (v/v); KPS, 3.4 × 10?3 mole/l; temp., 90°C.  相似文献   
60.
Recently, the problem of absorption of gases into nonhomogeneous solvents has drawn more attention than ever as it found in various fields such as flue gas scrubbing, hydroprocessing, coal conversion and medicine. Since the first treatment of this problem by Ramachandran and Sharma(1), several models based on the film concept have been proposed(2-7). There is, however, no penetration theory for the evaluation of the rate of the absorption of a gas into a slurry containing suspended solid particles. In this paper, a penetration model is presented for the absorption of gas A into a slurry containing solid B with an instantaneous irreversible chemical reaction.  相似文献   
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