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1.
Normative KGP agents 总被引:1,自引:0,他引:1
Fariba Sadri Kostas Stathis Francesca Toni 《Computational & Mathematical Organization Theory》2006,12(2-3):101-126
We extend the logical model of agency known as the KGP model, to support agents with normative concepts, based on the roles
an agent plays and the obligations and prohibitions that result from playing these roles. The proposed framework illustrates
how the resulting normative concepts, including the roles, can evolve dynamically during the lifetime of the agent. Furthermore,
we illustrate how these concepts can be combined with the existing capabilities of KGP agents in order to plan for their goals,
react to changes in the environment, and interact with other agents. Our approach gives an executable specification of normative
concepts that can be used directly for prototyping applications.
Fariba Sadri is a senior lecturer at Imperial College London, from where she received her PhD. Her earlier work concentrated on integrity
of deductive databases and temporal reasoning, in particular using the event calculus. In more recent years her work has been
on agent technologies and multi-agent systems. She has worked on logic-based agent models, reasoning, dynamic belief revision,
and inter-agent communication and negotiation for resources. She was co-awarded an EPSRC grant for research into logic-based
multi-agents and was co-investigator in the EU SOCS project.
Kostas Stathis is a senior lecturer at Royal Holloway, University of London and he holds a PhD from Imperial College London. His research
interests are in the area of computational intelligence in general and in the intersection of computational logic and cognitive
systems for social computing applications in particular. His research interests include: representation of human-computer
(or computer-computer) interaction as a game; cognitive & autonomous agents; artificial agent societies; agent communication;
programmable agents and agent platforms. He is a co-investigator of the EU ArguGRID project and was a co-investigator of the
EU SOCS project.
Francesca Toni is a senior lecturer at Imperial College London, from where she received her PhD. Her earlier work focused on abductive reasoning.
In more recent years, she focused on argumentation, agent models and multi-agent systems. She has worked on computational
logic-based agent models, agent reasoning, dynamic belief revision, and inter-agent communication and negotiation for resources.
She has been co-ordinator of the EU SOCS project, which developed the KGP model of agency, and is coordinator of the EU ArguGRID
project, on the application of argumentative agents within grid systems. 相似文献
2.
P. Dimopoulos K. Farakos S. Nicolis 《The European Physical Journal C - Particles and Fields》2002,24(2):287-296
We explore the phase diagram of the five-dimensional anisotropic Abelian Higgs model by Monte Carlo simulations. In particular,
we study the transition between the confining phase and the four-dimensional layered Higgs phase. We find that, in a certain
region of the lattice parameter space, this transition can be first order, and that each layer moves into the Higgs phase
independently of the others (decoupling of layers). As the Higgs couplings vary, we find, using mean field techniques, that
this transition may probably become second order.
Received: 21 December 2001 / Published online: 12 April 2002 相似文献
3.
Bianco A Kostarelos K Partidos CD Prato M 《Chemical communications (Cambridge, England)》2005,(5):571-577
The organic functionalisation of carbon nanotubes can improve substantially their solubility and biocompatibility profile; as a consequence, their manipulation and integration into biological systems has become possible so that functionalised carbon nanotubes hold currently strong promise as novel systems for the delivery of drugs, antigens and genes. 相似文献
4.
Binding and condensation of plasmid DNA onto functionalized carbon nanotubes: toward the construction of nanotube-based gene delivery vectors 总被引:10,自引:0,他引:10
Singh R Pantarotto D McCarthy D Chaloin O Hoebeke J Partidos CD Briand JP Prato M Bianco A Kostarelos K 《Journal of the American Chemical Society》2005,127(12):4388-4396
Carbon nanotubes (CNTs) constitute a class of nanomaterials that possess characteristics suitable for a variety of possible applications. Their compatibility with aqueous environments has been made possible by the chemical functionalization of their surface, allowing for exploration of their interactions with biological components including mammalian cells. Functionalized CNTs (f-CNTs) are being intensively explored in advanced biotechnological applications ranging from molecular biosensors to cellular growth substrates. We have been exploring the potential of f-CNTs as delivery vehicles of biologically active molecules in view of possible biomedical applications, including vaccination and gene delivery. Recently we reported the capability of ammonium-functionalized single-walled CNTs to penetrate human and murine cells and facilitate the delivery of plasmid DNA leading to expression of marker genes. To optimize f-CNTs as gene delivery vehicles, it is essential to characterize their interactions with DNA. In the present report, we study the interactions of three types of f-CNTs, ammonium-functionalized single-walled and multiwalled carbon nanotubes (SWNT-NH3+; MWNT-NH3+), and lysine-functionalized single-walled carbon nanotubes (SWNT-Lys-NH3+), with plasmid DNA. Nanotube-DNA complexes were analyzed by scanning electron microscopy, surface plasmon resonance, PicoGreen dye exclusion, and agarose gel shift assay. The results indicate that all three types of cationic carbon nanotubes are able to condense DNA to varying degrees, indicating that both nanotube surface area and charge density are critical parameters that determine the interaction and electrostatic complex formation between f-CNTs with DNA. All three different f-CNT types in this study exhibited upregulation of marker gene expression over naked DNA using a mammalian (human) cell line. Differences in the levels of gene expression were correlated with the structural and biophysical data obtained for the f-CNT:DNA complexes to suggest that large surface area leading to very efficient DNA condensation is not necessary for effective gene transfer. However, it will require further investigation to determine whether the degree of binding and tight association between DNA and nanotubes is a desirable trait to increase gene expression efficiency in vitro or in vivo. This study constitutes the first thorough investigation into the physicochemical interactions between cationic functionalized carbon nanotubes and DNA toward construction of carbon nanotube-based gene transfer vector systems. 相似文献
5.
Dr. Peter Wick Dr. Anna E. Louw‐Gaume Dr. Melanie Kucki Prof. Harald F. Krug Prof. Kostas Kostarelos Prof. Bengt Fadeel Prof. Kenneth A. Dawson Dr. Anna Salvati Prof. Ester Vázquez Dr. Laura Ballerini Dr. Mauro Tretiach Dr. Fabio Benfenati Dr. Emmanuel Flahaut Dr. Laury Gauthier Prof. Maurizio Prato Dr. Alberto Bianco 《Angewandte Chemie (International ed. in English)》2014,53(30):7714-7718
6.
7.
Kostas Kounetas 《Central European Journal of Operations Research》2014,22(4):623-645
This paper examines the technical efficiency of Greek football clubs, taking into account the period before the Euro 2004 victory and the period thereafter. The first stage of analysis is based on a bootstrapped data envelopment analysis approach so as to determine Greek clubs’ efficiency scores during these two distinct time periods. The second stage of analysis investigates possible factors that may have affected the efficiency scores during the examined periods. Our findings reveal that Greek football clubs exhibit surprisingly lower efficiency scores after Euro victory. In effect and explained in the context of the Resource Based Theory, there appears to be no classification of types of football clubs into various divisions, viz. laggards, followers and champions. Finally, it is also found that clubs’ financial health appears to be a crucial factor for their performance in both periods. 相似文献
8.
9.
N. A. Batakis K. Farakos D. Kapetanakis G. Koutsoumbas G. Zoupanos 《Physics letters. [Part B]》1989,220(4):513-519
We consider the compactification of ten-dimensional Einstein-Yang-Mills theories over non-symmetric, six-dimensional homogeneous coset spaces with torsion. We examine the Einstein-Yang-Mills equations of motion requiring vanishing cosmological constant at ten and four dimensions and we present examples of compactictifying solutions. It appears that the introduction of more than one radii in the coset space, when possible, may be mandatory for the existence of compactifying solutions. 相似文献
10.
A tris(bromo-methylphenylene)triazine and its corresponding phosphine oxide derivative have been synthesized; the latter compound was found to be a potent ligand for the hydroformylation reaction. Suzuki coupling of the mono-pinacolboronate derivative of the former compound with a tris(iodo-methylphenylene)triazine was possible at two of the three iodine atoms, yielding a bromo- and iodo-methylphenylene periphery-functionalized triazine-based dendritic molecule with a 3,3′-dimethyl-biphenyl linker. 相似文献