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991.
Josef Ruppenhofer Russell Lee-Goldman Caroline Sporleder Roser Morante 《Language Resources and Evaluation》2013,47(3):695-721
Semantic role labeling is traditionally viewed as a sentence-level task concerned with identifying semantic arguments that are overtly realized in a fairly local context (i.e., a clause or sentence). However, this local view potentially misses important information that can only be recovered if local argument structures are linked across sentence boundaries. One important link concerns semantic arguments that remain locally unrealized (null instantiations) but can be inferred from the context. In this paper, we report on the SemEval 2010 Task-10 on “Linking Events and Their Participants in Discourse”, that addressed this problem. We discuss the corpus that was created for this task, which contains annotations on multiple levels: predicate argument structure (FrameNet and PropBank), null instantiations, and coreference. We also provide an analysis of the task and its difficulties. 相似文献
992.
Ayesh AI Lassesson A Brown SA Dunbar AD Kaufmann M Partridge JG Reichel R van Lith J 《The Review of scientific instruments》2007,78(5):053906
The operation conditions of a double pulsed field mass filter were studied using both experiment and simulation. The mass filter consists of two pairs of parallel plates and operates on the time-of-flight principle. The study showed that the ions' beam deflection angle is a critical factor in optimizing the mass filter transmission efficiency. This angle is dependent on the accelerating voltage, ion mass, and horizontal velocity of the ions. The optimum operating conditions for the mass filter were found and used to study the mass distribution of palladium ions produced by a magnetron sputtering source. The study shows that this mass filter is suitable for technological applications because of its high transmission and wide mass range. 相似文献
993.
This paper describes the influence of a termination of ended carboxyl groups of ethylene glycol–maleic anhydride–phtalic anhydride polyesters with cyclohexanole on a position of phase interface of the unsaturated polyester–styrene system. At given temperatures, optimal molecular weights were determined for the achievement of maximal miscibility of this polymer with styrene. Simultaneously, a model implicit equation was proposed, which is based on the assumption that the dependence of the interaction parameter χ on number-average molecular weights is similar to that dependence of the interaction parameter χ on temperature. Solution of these implicit equation are isotherms in the phase diagram M n??2?Tcloude point. 相似文献
994.
995.
Daniel Hork Frantiek vec Michal Ilavský Miroslav Bleha Josef Baldrin Jaroslav Klal 《大分子材料与工程》1981,95(1):117-127
By the method of design of experiments, the influence of the content and the thermodynamic quality of the mixture of inert solvents (porogenic compounds), of the concentration of the crosslinking agent and initiator in the polymerization mixture and of the reaction temperature in the radical suspension copolymerization was investigated with respect to the pore size, the porosity and the mechanical properties of macroporous copolymers from glycidylmethacrylate and ethylenedimethacrylate. It was found that the predominant effect on these characteristics should be attributed to the volume of the porogenic component in the mixture, and that the pore size and porosity increase at the same time the penetration modulus and the stress-at-break decrease proportionately to this volume. The concentration of the crosslinking agent has an influence only at low crosslinking values. The polymerization temperature and concentration of the initiator have only an insignificant effect on the structure and mechanical properties. 相似文献
996.
The Composition of Animal Organ and Depot Fats in Relation to Feed III: Gas-chromatographic Analysis of Fats from Calves after Definite Feed Within the scope of the feeding experiments, which had been carried out for explaining the accumulation of trans fatty acids in animal organs, we studied the composition of mixed fatty acids of heart, kidney and liver as well as that of the corresponding depot fats with the help of gas-chromatography. The fatty acid composition of the separated neutral fat and phosphatide fractions of the organ fats are discussed. 相似文献
997.
David F. Fouhey Vincent Delaitre Abhinav Gupta Alexei A. Efros Ivan Laptev Josef Sivic 《International Journal of Computer Vision》2014,110(3):259-274
We present an approach which exploits the coupling between human actions and scene geometry to use human pose as a cue for single-view 3D scene understanding. Our method builds upon recent advances in still-image pose estimation to extract functional and geometric constraints on the scene. These constraints are then used to improve single-view 3D scene understanding approaches. The proposed method is validated on monocular time-lapse sequences from YouTube and still images of indoor scenes gathered from the Internet. We demonstrate that observing people performing different actions can significantly improve estimates of 3D scene geometry. 相似文献
998.
This article deals with the alkaline hydrolysis of ethyl acrylate–acrylonitrile–divinylbenzene copolymer beads. Chemical changes during hydrolysis were evaluated by means of determination of total weight exchange capacity and of infrared spectroscopy. The influence of reaction temperature, concentration of the hydrolytic agent, degree of copolymers crosslinking as well as the influence of particle size upon the rate of hydrolysis were studied as a function of time. The mathematical and statistical calculations of experimental data were carried out. With respect to time dependence of hydrolysis of the copolymer functional groups, the average values of reaction rate constants as well as the values of assumed diffusion coefficients were calculated. The analysis is based on partial linearization of experimental results by means of semilogarithmic transformation. The empirical relations expressing dependences of reaction rate constants and of diffusion coefficients on conditions of hydrolysis were determined. 相似文献
999.
The effect of titanium compounds on thermooxidation stability of stabilized polypropylene was studied. It was found that the presence of titanium compounds shortens the induction period of PP oxidation. This phenomenon is brought about by the thermal reactions of titanium compounds with antioxidants which take place during polymer processing. The first step is the reaction of Ti? Cl with OH groups of phenolic antioxidant, which gives rise to a colored titanate and HCl. Hydrogen chloride functions as a Friedel-Crafts catalyst for degradation and dealkylation of phenolic antioxidants. The products of degradation have a very low stabilization efficiency. Hydrogen chloride acceptors suppress antioxidant degradation and increase the polymer stability even in the presence of small amounts of titanium compounds. 相似文献
1000.
The dependences of phase structure and notch impact strength on conditions of mixing have been compared for the binary blend PP/EPDM and for two ternary blends PP/EPDM/PE possessing different viscosities of polyethylene. At low rates and short times of mixing a phase structure with pronounced inhomogeneities (particles of the dispersed phase having diameters of tens μm) is formed in all blends. Conditions of mixing needed for the formation of a homogeneous phase structure (with particles having diameters of several μm) depend on the average viscosity of the components forming the inclusions (EPDM elastomer or EPDM elastomer/polyethylene). Depending on the conditions of mixing and on the rheological properties of components, substitution of one part of the EPDM elastomer with PE may lead to an increase or decrease in the impact strength of the final blend. 相似文献