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991.
992.
Nodine M.M. Ngu A.H.H. Cassandra A. Bohrer W.G. 《Knowledge and Data Engineering, IEEE Transactions on》2003,15(5):1082-1098
InfoSleuth is an agent-based system for information discovery and retrieval in a dynamic, open environment. Brokering in InfoSleuth is a matchmaking process, recommending agents that provide services to agents requesting services. This paper discusses InfoSleuth's distributed multibroker design and implementation. InfoSleuth's brokering function combines reasoning over both the syntax and semantics of agents in the domain. This means the broker must reason over explicitly advertised information about agent capabilities to determine which agent can best provide the requested services. Robustness and scalability issues dictate that brokering must be distributable across collaborating agents. Our multibroker design is a peer-to-peer system that requires brokers to advertise to and receive advertisements from other brokers. Brokers collaborate during matchmaking to give a collective response to requests initiated by nonbroker agents. This results in a robust, scalable brokering system. 相似文献
993.
Bing Q. Han Farghalli A. Mohamed Enrique J. Lavernia 《Metallurgical and Materials Transactions A》2003,34(1):71-83
In the present study, the mechanical properties of Fe processed via severe plastic deformation (equal-channel angular pressing (ECAP)) at room temperature were investigated for the first time.
The grain size of annealed Fe, with an initial grain size of about 200 μm, was reduced drastically during ECAP. After eight passes, the grain size reaches 200 to 400 nm, as documented by means of
transmission electron microscopy (TEM). The value of microhardness during pressing increases 3 times over that of the starting
material after the first pass and increases slightly during subsequent pressing for higher-purity Fe. Examination of the value
of microhardness after eight passes as a function of post-ECAP annealing temperature shows a transition from recovery to recrystallization,
an observation that resembles the behavior reported for heavily deformed metals and alloys. The tensile and compression behaviors
were examined. In tension, a drop in the engineering stress-engineering strain curve beyond maximum load was observed both
in the annealed Fe and the ECAP Fe. This drop is related to the neck deformation. The fracture surface, examined by scanning
electron microscopy (SEM), shows vein patterns, which is different from the dimples found on the fracture surface of annealed
Fe. In compression, an initial strain-hardening region followed by a no-strain-hardening region was observed in the ECAP Fe.
The yield strength in tension of the ECAP Fe was observed to be higher than that in compression. The strengthening mechanisms
and softening behavior are discussed. 相似文献
994.
A. M. Skorobogatov A. V. Tvardovskii 《Journal of Engineering Physics and Thermophysics》2007,80(3):634-637
A model for calculating of the change in the basic thermodynamic characteristics of a sorbent (internal energy and entropy)
with the phenomenological-thermodynamics method has been developed. Calculations for the systems polycarbonate-carbon dioxide
and polymethylmethacrylate-carbon dioxide have been carried out.
__________
Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 80, No. 3, pp. 198–200, May–June, 2007. 相似文献
995.
996.
Interventions for a variety of emotional and behavioral problems are commonly delivered in the context of treatment groups, with many using rolling admission to sustain membership (i.e., admission, dropout, and discharge from group are perpetual and ongoing). The authors present an overview of the analytic challenges inherent in rolling group data and outline commonly used (but flawed) analytic and design approaches to addressing (or sidestepping) these issues. Moreover, the authors propose use of latent class pattern mixture models (LCPMMs) as a statistically and conceptually defensible approach for modeling treatment data from rolling groups. The LCPMM approach is illustrated with rolling group data from a group-based alcoholism pilot treatment trial (N = 128). Different inferences were made with regard to treatment efficacy under LCPMM vs. the commonly used standard group-clustered latent growth model (LGM); coupled with other preliminary findings in this area, inferences from LGMs may be overly liberal when applied to data from rolling groups. Continued work on data analytic difficulties in groups with membership turnover is critical for furthering the ecological validity of research on behavioral treatments. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
V. A. Sychevskii N. V. Pavlyukevich L. L. Vasil'ev S. Rozin 《Journal of Engineering Physics and Thermophysics》2003,76(1):18-27
A problem of the Stefan type which describes heat and mass transfer in a porous body with the double phase transition liquid–ice–vapor has been formulated and solved. 相似文献
998.
999.
J. R. Díaz-Estrada E. Camps L. Escobar-Alarcón J. A. Ascencio 《Journal of Materials Science》2007,42(4):1360-1368
Deposition of Ti was carried out by laser ablation onto hydroxyapatite porous discs in an Ar atmosphere. Ti nanoparticles
were deposited onto HAp surface in order to modify its roughness and morphology as it is observed by scanning electron microscopy
(SEM) and scanning probe microscopy (SPM). A homogeneous distribution of Ti over the disc surface was corroborated by elemental
mapping. A comparison of the hydroxyapatite hardness before and after deposition was performed using SPM nanoindentation.
Transmission Electron Microscopy (TEM) showed that the Ti nanoparticles obtained were covered by an oxygen shell. It is shown
that surface modifications of the covered HAp by Ti result in better mechanical properties, reducing the possible damage to
the HAp ceramic by friction or impacts as it often happens in meniscus, bone junctions and the inclusion of prosthesis for
human treatments. 相似文献
1000.
Pupils' recall of an interactive storybook on CD-ROM 总被引:1,自引:0,他引:1
Abstract This small-scale study compares two groups of Year 4 (8/9 year-old) pupils either reading or playing an interactive storybook . The study considered pupils' recall of propositions, which formed the story setting and episodes, and of micro-propositions and characters' names, and pupils' responses to inferential items derived from the 'interactive storybook'. The study indicates that, whether reading or playing, pupils' recall of the story setting was sound, but pupils who had read the interactive storybook demonstrated greater recall of the story event structure than those who had engaged in interactive picture-play. Pupils who had played the interactive storybook demonstrated significantly greater recall of micro-propositions and names. 相似文献