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21.
Roberto Barbuti Nicoletta De Francesco Antonella Santone Gigiola Vaglini 《Formal Methods in System Design》2000,17(3):201-220
When verifying concurrent systems described by transition systems, state explosion is one of the most serious problems. If quantitative temporal information (expressed by clock ticks) is considered, state explosion is even more serious. We present a notion of abstraction of transition systems, where the abstraction is driven by the formulae of a quantitative temporal logic, called qu-mu-calculus, defined in the paper. The abstraction is based on a notion of bisimulation equivalence, called , n-equivalence, where is a set of actions and n is a natural number. It is proved that two transition systems are , n-equivalent iff they give the same truth value to all qu-mu-calculus formulae such that the actions occurring in the modal operators are contained in , and with time constraints whose values are less than or equal to n. We present a non-standard (abstract) semantics for a timed process algebra able to produce reduced transition systems for checking formulae. The abstract semantics, parametric with respect to a set of actions and a natural number n, produces a reduced transition system , n-equivalent to the standard one. A transformational method is also defined, by means of which it is possible to syntactically transform a program into a smaller one, still preserving , n-equivalence. 相似文献
22.
Agent communication and artificial institutions 总被引:1,自引:0,他引:1
Nicoletta Fornara Francesco Viganò Marco Colombetti 《Autonomous Agents and Multi-Agent Systems》2007,14(2):121-142
In this paper we propose an application-independent model for the definition of artificial institutions that can be used to
define open multi-agent systems. Such a model of institutional reality makes us able also to define an objective and external
semantics of a commitment-based Agent Communication Language (ACL). In particular we propose to regard an ACL as a set of
conventions to act on a fragment of institutional reality, defined in the context of an artificial institution. Another contribution
of the work presented in this paper is an operational definition of norms, a crucial component of artificial institutions.
In fact in open systems interacting agents might not conform to the specifications. We regard norms as event-driven rules
that when are fired by events happening in the system create or cancel a set of commitments. An interesting aspect of our
proposal is that both the definition of the ACL and the definition of norms are based on the same notion of commitment. Therefore
an agent capable of reasoning on commitments can reason on the semantics of communicative acts and on the system of norms. 相似文献
23.
Elisabetta Fanizza Carmine Urso R. Maria Iacobazzi Nicoletta Depalo Michela Corricelli Annamaria Panniello 《Science and Technology of Advanced Materials》2016,17(1):98-108
Silica based multifunctional heterostructures, exhibiting near infrared (NIR) absorption (650–1200 nm) and luminescence in the visible region, represent innovative nanosystems useful for diagnostic or theranostic applications. Herein, colloidal synthetic procedures are applied to design a photoactive multifunctional nanosystem. Luminescent silica (SiO2) coated quantum dots (QDs) have been used as versatile nanoplatforms to assemble on their surface gold (Au) seeds, further grown into Au spackled structures. The synthesized nanostructures combine the QD emission in the visible region, and, concomitantly, the distinctive NIR absorption of Au nanodomains. The possibility of having multiple QDs in a single heterostructure, the SiO2 shell thickness, and the extent of Au deposition onto SiO2 surface have been carefully controlled. The work shows that a single QD entrapped in 16 nm thick SiO2 shell, coated with Au speckles, represents the most suitable geometry to preserve the QD emission in the visible region and to generate NIR absorption from metal NPs. The resulting architectures present a biomedical potential as an effective optical multimodal probes and as promising therapeutic agents due to the Au NP mediated photothermal effect. 相似文献
24.
Nicoletta Sinelli Lorenzo Cerretani Valentina Di Egidio Alessandra Bendini Ernestina Casiraghi 《Food research international (Ottawa, Ont.)》2010,43(1):369-375
A sensory analysis of 112 virgin olive oils was performed by a fully trained taste panel. The samples were divided in “defective” and “not defective” on the basis of their olfactory attributes. Then, the “not defective” samples were classified into “low”, “medium” and “high” according to the fruity aroma intensity perceived by assessors. All samples were also analysed by FT-NIR and FT-IR spectroscopy and processed by classification methods (LDA and SIMCA). The results showed that NIR and MIR spectroscopy coupled with statistical methods are an interesting technique compared with traditional sensory assessment in classifying olive oil samples on the basis of the fruity attribute. The prediction rate varied between 71.6% and 100%, as average value. The spectroscopic methods, combined with chemometric strategies, could represent a reliable, cheap and fast classification tool, able to draw a complete fingerprint of a food product, describing its intrinsic quality attributes, that include its sensory attributes. 相似文献
25.
Federica Zaccheria Rinaldo Psaro Nicoletta Ravasio Laura Sordelli Federica Santoro 《Catalysis Letters》2011,141(4):587-591
Abstract
Styrene oxide can be effectively isomerized to phenyl-acetaldehyde (98%) over amorphous silica alumina catalysts under very mild liquid phase conditions. On the other hand, a copper catalyst prepared using a silica zirconia support gave up to 80% yield in the hydrogenation of styrene oxide to 2-phenyl-ethanol. 相似文献26.
Rosalba Lanciotti Francesca Patrignani Luciana Iucci Maria Elisabetta Guerzoni Giovanna Suzzi Nicoletta Belletti Fausto Gardini 《Food chemistry》2007,104(2):693-701
The aim of this work was to evaluate the biogenic amine (BA) content during the ripening of both bovine and ovine cheeses obtained using milk subjected to a homogenization treatment at 100 MPa before cheese-making. The data obtained were compared with those from cheeses produced by the same milks without any treatment or thermized. The results showed that both microbial ecology and BA concentrations of cheeses during ripening were significantly influenced by the type of milk used for cheese-making and by the treatment applied to the raw materials. In particular, the microbial counts found in Caciotta indicated that the high pressure homogenization (HPH) of milk significantly reduced the presence of the yeasts, Micrococcaceae and lactobacilli at the end of ripening. On the other hand, the HPH treatment of milk favoured the proliferation of yeasts in ovine cheese. Moreover, the ovine cheeses were characterized by a remarkably higher accumulation of BA than bovine cheeses. However, the HPH treatment of milk was able to drastically reduce the biogenic amine concentrations in both cheese typologies at the end of ripening. 相似文献
27.
Online 3D Shared Spaces (3DSSs) can be regarded as a frontier of the Web 2.0, where users as participants contribute to create a meaningful, engaging experience. Like other complex web applications, the development and evolution
of high-quality 3DSS applications requires methodological support—through models, methods, and principles. Yet, the application
of structured, engineered approaches to this domain is largely unexplored. The purpose of this paper is to contribute to bridging
Web Engineering to the 3DSS world by means of design patterns. We present five patterns that focus on two factors deemed necessary for effective experiences in a 3DSS: Presence (i.e. the feeling of “being there”, typical of “virtual worlds”) and Long-Term Engagement (typical of successful Web 2.0 communities). The patterns presented in the paper distil our large-scale experiences with
3DSSs (that have involved so far over 9,000 youngsters from 3 continents) and are discussed in the light of existing literature. 相似文献
28.
F.P. Nicoletta G. Chidichimo D. Cupelli G. DeFilpo M. DeBenedittis B. Gabriele G. Salerno A. Fazio 《Advanced functional materials》2005,15(6):995-999
Polymer‐dispersed liquid crystals (PDLCs) are liquid‐crystal dispersions within a polymer matrix. These films can be changed from an opaque to a transparent state by applying a suitable alternating‐current electric field. PDLCs have attracted the interest of researchers for their applications as light shutters, smart windows, and active displays. For such applications, electrochromic devices, which change color as a result of electrochemical reactions, have also become a recent focus of research. Herein, we report our preliminary results on bifunctional devices based on PDLCs that host electrochromic guest molecules. Such devices allow both an independent and fast switching from a scattering opaque state to a transmissive transparent state owing to liquid‐crystal reorientation and a color change from white (pale yellow) to dark blue, due to either oxidation or reduction of the electrochromic molecules. 相似文献
29.
Synthesis and Antiplasmodial Activity of Novel Chloroquine Analogues with Bulky Basic Side Chains
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Dr. Bruno Tasso Dr. Federica Novelli Dr. Michele Tonelli Dr. Anna Barteselli Dr. Nicoletta Basilico Dr. Silvia Parapini Prof. Donatella Taramelli Prof. Anna Sparatore Prof. Fabio Sparatore 《ChemMedChem》2015,10(9):1570-1583
Chloroquine is commonly used in the treatment and prevention of malaria, but Plasmodium falciparum, the main species responsible for malaria‐related deaths, has developed resistance against this drug. Twenty‐seven novel chloroquine (CQ) analogues characterized by a side chain terminated with a bulky basic head group, i.e., octahydro‐2H‐quinolizine and 1,2,3,4,5,6‐hexahydro‐1,5‐methano‐8H‐pyrido[1,2‐a][1,5]diazocin‐8‐one, were synthesized and tested for activity against D‐10 (CQ‐susceptible) and W‐2 (CQ‐resistant) strains of P. falciparum. Most compounds were found to be active against both strains with nanomolar or sub‐micromolar IC50 values. Eleven compounds were found to be 2.7‐ to 13.4‐fold more potent than CQ against the W‐2 strain; among them, four cytisine derivatives appear to be of particular interest, as they combine high potency with low cytotoxicity against two human cell lines (HMEC‐1 and HepG2) along with easier synthetic accessibility. Replacement of the 4‐NH group with a sulfur bridge maintained antiplasmodial activity at a lower level, but produced an improvement in the resistance factor. These compounds warrant further investigation as potential drugs for use in the fight against malaria. 相似文献
30.