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排序方式: 共有186条查询结果,搜索用时 109 毫秒
1.
Thermal conductivity of apple and potato samples was measured by means of a specifically designed apparatus based on Fitch's method. The thermal conductivity was determined at various moisture contents at the sample mean temperature of 30 °C. As expected the conductivity decreases with the decrease in moisture content. Thermal conductivity data were correlated with moisture content using a straight line. 相似文献
2.
Franco Cicirelli Angelo Furfaro Andrea Giordano Libero Nigro 《Simulation Modelling Practice and Theory》2011,19(1):283-300
RePast is a popular agent toolkit with proven capabilities to fulfil the modelling challenges of large multi-agent systems (MASs). The toolkit, though, is normally used on a standalone workstation and therefore its practical use can be constrained (in space and time) by the limited available computing resources. This paper proposes an original approach – HLA_ACTOR_REPAST – aimed to distributing RePast models for high-performance simulation of complex scalable models. Novel in HLA_ACTOR_REPAST is an exploitation of a lean actor infrastructure implemented in Java. Actors bring to RePast agents such features as migration, location-transparent naming, efficient communications, and a control-centric framework. Actors can be orchestrated by an in-the-large custom control structure which is in charge of ensuring the necessary message causality constraints. Distribution and time management concerns depend on the IEEE standard HLA middleware. The paper first discusses details of the software engineering process underlying the development of HLA_ACTOR_REPAST. The mapping techniques, assisted by Java text annotations and aspect-oriented programming, try to minimize “code intrusions” in the original model and favour model transparency. The paper then furnishes some experimental data which witness the good performance results achieved by applying HLA_ACTOR_REPAST to a distributed version of a classic MAS benchmark model. 相似文献
3.
Silvia Franco Elena Buratti Valentina Nigro Emanuela Zaccarelli Barbara Ruzicka Roberta Angelini 《International journal of molecular sciences》2021,22(8)
The phase behaviour of soft colloids has attracted great attention due to the large variety of new phenomenologies emerging from their ability to pack at very high volume fractions. Here we report rheological measurements on interpenetrated polymer network microgels composed of poly(N-isopropylacrylamide) (PNIPAM) and polyacrylic acid (PAAc) at fixed PAAc content as a function of weight concentration. We found three different rheological regimes characteristic of three different states: a Newtonian shear-thinning fluid, an attractive glass characterized by a yield stress, and a jamming state. We discuss the possible molecular mechanisms driving the formation of these states. 相似文献
4.
5.
Giuseppe Spoto Silvia Bordiga Domenica Scarano Adriano Zecchina 《Catalysis Letters》1992,13(1-2):39-44
In this note an exchange procedure of the acidic protons of H-ZSM5 by CuI ions through reaction with CuCl in the gas phase is described. In the so obtained CuI-ZSM5 exchanged zeolite the CuI ions are in well defined configuration and form with NO mono and di-nitrosyl complexes of high structural and spectroscopic quality. The CuI(NO)2 species are transformed at RT into CuII(NO)X (X=O– and/or NO
2
–
) species which could represent an intermediate in NO decomposition. 相似文献
6.
The area of free radical biology is of increasing interest for marine organisms since the enhanced formation of reactive oxygen species (ROS) is a common pathway of toxicity induced by stressful environmental conditions. In polar environments responses of the antioxidant system could be useful as an early detection biomarkers of unforeseen effects of human activities which are progressively increasing in these remote areas. However, the characterization of antioxidant defences in appropriate sentinel species is of particular value also in terms of a possible adaptation to this extreme environment. The scallop, Adamussium colbecki, is a key species for monitoring the Antarctic environment and, besides single antioxidants, the total oxyradical scavenging capacity (TOSC) assay has been recently used for quantifying the overall ability of this organism to neutralize peroxyl radicals (ROO*), hydroxyl radicals (*OH) and peroxynitrite (HOONO). The aim of this work was to obtain a better characterization of these biological responses which can indicate the occurrence of biological disturbance; in this study the total oxyradical scavenging capacity was further analyzed to assess the presence of seasonal fluctuations in the susceptibility to oxidative stress in this species. The capability to neutralize peroxyl radicals and hydroxyl radicals increased at the end of December, while resistance towards peroxynitrite did not show any significant variations during the Antarctic summer. These results suggest the occurrence of metabolic changes which mainly influence intracellular formation of ROO* and *OH, with more limited effects on HOONO. Despite the limited time window analyzed, as a typical constraint in Antarctic research at Terra Nova Bay, an increased resistance to these specific oxyradicals might be related to the period of highest feeding activity, or to other intrinsic factors in the animals' physiology such as the phase of reproductive cycle. 相似文献
7.
The breakdown (BD) kinetics of dielectrics represent a crucial issue for the reliability of microelectronics devices. In this paper, we report on an innovative and practical approach based on Conductive Atomic Force Microscopy (C-AFM) for the determination of the BD kinetics on a bare insulator surface. This technique has been applied to Pr2O3 films grown by Metal-Organic Chemical Vapour Deposition (MOCVD) on Si(0 0 1) and to thermally grown SiO2 on 4H-SiC substrates. C-AFM clearly visualizes single breakdown spots under constant voltage stresses. The stress time on the C-AFM tip was varied from 1 × 10−3 to 1 × 10−1 s. The density of BD spots, upon increasing the stress time, exhibits in both cases an exponential trend. The Weibull slope of the dielectric BD statistics has been determined by direct measurements at nanometer scale on different dielectrics having different physical thicknesses. The comparison of the Weibull slopes obtained for different dielectric thicknesses with literature data points out intrinsic and extrinsic BD events in the SiO2/SiC system and Pr2O3 based layers, respectively. In the case of the SiO2/SiC system, BD kinetics have been demonstrated to follow the percolation model, while the role of extrinsic phenomena in the BD of Pr2O3 films has been proved. 相似文献
8.
In this article, we address detectability for the class of linear switching systems. We focus on some hybrid state-space decompositions of the original switching system based on hybrid invariant subspaces, which yield a complexity reduction in checking detectability. We show that the reduced system extracted from the original system is the minimal bisimilar switching system associated with it. An example is also included which shows the applicability and benefits of the proposed approach. 相似文献
9.
This paper proposes a novel approach centered on multimedia internetworking for the development of Distributed Virtual Instruments (DVI). Multimedia internetworking refers to network infrastructures, protocols, models, applications and techniques being currently deployed over the Internet to support multimedia applications, e.g., videoconferencing, video-on-demand, shared workspaces. It is applied to broaden the concept of virtual instrument and enable new measurement patterns leveraging efficiency and interactivity. A DVI is a virtual instrument split into possibly multiple and independent parts, sender and receiver, which are linked by real-time continuous media and control streams. Senders and receivers are built by using open, composable and modular components based on a time sensitive actor framework and glued by multimedia middleware. A prototype is described to demonstrate the potential and the benefits of the proposed approach. 相似文献
10.
Sergio R. Idelsohn Monica Mier-Torrecilla Norberto Nigro Eugenio Oñate 《Computational Mechanics》2010,46(1):115-124
Heterogeneous incompressible fluid flows with jumps in the viscous properties are solved with the particle finite element
method using continuous and discontinuous pressure fields. We show the importance of using discontinuous pressure fields to
avoid errors in the incompressibility condition near the interface. 相似文献