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41.
Distributed message relaying is an important function of a peer-to-peer system to discover service providers. Existing search protocols in unstructured peer-to-peer systems create huge burden on communications, cause long response time, or result in unreliable performance. Moreover, with self-interested peers, these systems are vulnerable to the free-riding problem. In this paper we present an incentive mechanism that not only mitigates the free-riding problem, but also achieves good system efficiency in message relaying for peer discovery. In this mechanism promised rewards are passed along the message propagation process. A peer is rewarded if a service provider is found via a relaying path that includes this peer. The mechanism allows peers to rationally trade-off communication efficiency and reliability while maintaining information locality. We provide some analytic insights to the symmetric Nash equilibrium strategies of this game, and an approximate approach to calculate this equilibrium. Experiments show that this incentive mechanism brings a system utility generally higher than breadth-first search and random walks, based on both the estimated utility from our approximate equilibrium and the utility generated from learning in the incentive mechanism. 相似文献
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Jean Oh Felipe Meneguzzi Katia Sycara Timothy J. Norman 《Engineering Applications of Artificial Intelligence》2013,26(2):863-872
Human users planning for multiple objectives in complex environments are subjected to high levels of cognitive workload, which can severely impair the quality of the plans created. This paper describes a software agent that can proactively assist cognitively overloaded users by providing normative reasoning about prohibitions and obligations so that the user can focus on her primary objectives. In order to provide proactive assistance, we develop the notion of prognostic normative reasoning (PNR) that consists of the following steps: (1) recognizing the user's planned activities, (2) reasoning about norms to evaluate those predicted activities, and (3) providing necessary assistance so that the user's activities are consistent with norms. The idea of PNR integrates various AI techniques, namely, user intention recognition, normative reasoning over a user's intention, and planning, execution and replanning for assistive actions. In this paper, we describe an agent architecture for PNR and discuss practical applications. 相似文献
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46.
Shape-memory polymer networks from sol–gel cross-linked alkoxysilane-terminated poly(ε-caprolactone)
Katia Paderni Stefano Pandini Simone Passera Francesco Pilati Maurizio Toselli Massimo Messori 《Journal of Materials Science》2012,47(10):4354-4362
A novel type of covalently cross-linked semi-crystalline polymer with shape-memory and biocompatibility properties was prepared
from alkoxysilane-terminated poly(ε-caprolactone) (PCL) by sol–gel process that allowed the generation of silica-like cross-linking
points. A fine tuning of the cross-linking density and thermal properties (melting temperature) of the materials was obtained
by controlling the molecular weight of the PCL precursor (and thus the molecular structure of the resulting network) and the
curing conditions. The shape-memory behaviour was investigated with bending tests. Recovery times of less than one second
were observed in water depending on the temperature, and a linear correlation of the recovery time with cross-linking density
and molecular weight of PCL network precursor was observed. 相似文献
47.
Raquel Trujillano Miguel A. Vicente Vicente Rives Sophia A. Korili Antonio Gil Katia J. Ciuffi Eduardo J. Nassar 《Microporous and mesoporous materials》2009,117(1-2):309-316
Synthetic saponite containing Ni2+ as octahedral cations has been prepared by a simple hydrothermal procedure, and has been intercalated with Al13-polycations. The catalytic performance of the pillared solids in the epoxidation of (Z)-cyclooctene and the oxidation of cyclohexanone in the presence of benzonitrile, Baeyer–Villiger reaction, using hydrogen peroxide (70%) as a clean oxidant have been studied. For comparison, Mg-saponite was synthesized under the same conditions and tested for the same reaction. 相似文献
48.
Helio Langoni Carolina Polo Camargo da Silva Marcella Zampoli Troncarelli Alessandra Tata Katia Roberta Anacleto Belaz Marcos Nogueira Eberlin Samea Fernandes Joaquim Felipe Freitas Guimarães Renata Bonini Pardo Eduardo Nardini Gomes 《Journal of dairy science》2017,100(6):4287-4289
Corynebacterium bovis is a mastitis-causing microorganism responsible for economic losses related to decrease in milk production. The aim of the study was identify Corynebacterium spp. strains recovered from milk samples of subclinical mastitis by using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). Samples were collected during a 10-mo mastitis-monitoring program in a high-production dairy farm. In this study, 80 strains were analyzed; from these 54 (67.5%) were identified at species level as Corynebacterium bovis, 24 (31.2%) isolates were identified at the genus level as Corynebacterium spp., and only 1 (1.35%) isolated had unreliable identification. Results demonstrated that MALDI-MS could be an important technique for the identification of Corynebacterium spp. in milk. 相似文献
49.
Vincenzo Lo Turco Angela Giorgia Potortì Alessia Tropea Ermina Katia Casale Maria Rita Fede 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(11):1693-1699
Twenty-six plasticisers and bisphenol A (BPA) in 39 Sicilian and Calabrian nectar honeys of different botanical south Italian origin were determined by GC-MS. Di-(2-ethylhexyl)phthalate was the most abundant plasticiser in all samples, reaching up 202.7 ± 153.1 µg kg–1, followed by di-butylphthalate with a concentration of 40.3 ± 9.3 µg kg–1, whereas the concentration of the other phthalates varied from not detectable to 68.2 µg kg–1. Trace levels of adipate, sebacate and BPA were not detected in any samples. Among the different floral origin honeys, di-ethylphthalate levels were above the limit of quantification (LOQ) in orange blossom, wildflower and chestnut honey samples. Among the honeys of different geographical origin, di-methylphthalate, di-butylphthalate and di-(2-ethylhexyl)phthalate concentrations were similar. Calabrian honeys showed levels of di-ethylphthalate always lower than the LOQ, moreover di-(2-methylpropyl)phthalate levels were lower than the Sicilian ones. On the contrary, in Sicilian honeys di-(2-methylpropyl)phthalate levels were higher and di-ethylphthalate was present in 37% of samples. 相似文献
50.
Assessing the Potential Content of Ethyl Carbamate in White,Red, and Rosé Wines as a Key Factor for Pursuing Urea Degradation by Purified Acid Urease 下载免费PDF全文
Martina Cerreti Marcello Fidaleo Ilaria Benucci Katia Liburdi Pasquale Tamborra Mauro Moresi 《Journal of food science》2016,81(7):C1603-C1612
The ethyl carbamate (EC) content of a wine after a given temperature‐time storage was theoretically predicted from the potential concentration of ethyl carbamate (PEC), as determined via an accelerated EC formation test. Such information was used to decide whether an enzymatic treatment was needed to reduce the wine urea level before bottling/aging. To this end, 6 white, red, and rosé wines, manufactured in Italy as such or enriched with urea, were tested for their PEC content either before or after enzymatic treatment using a purified acid urease preparation derived from Lactobacillus fermentum. The treatment was severely affected by the total phenolic content (TP) of the wine, the estimated pseudo‐first‐order kinetic rate constant for NH3 formation reducing by a factor of approximately 2000 as the TP increased from 0 to 1.64 g L‐1. Such a sensitivity to TP was by far greater than that pertaining to a killed cell‐based enzyme preparation used previously. Urea hydrolysis was successful at reducing EC concentration in wines with low levels of TP and other EC precursors. 相似文献