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41.
Amanda Baker Michael Lanagan Clive Randall Elena Semouchkina George Semouchkin Khalid Z. Rajab Richard Eitel Khalid Z. Rajab Raj Mittra Sorah Rhee Peter Geggier Claus Duschl Günter Fuhr 《International Journal of Applied Ceramic Technology》2005,2(6):514-520
At the Keck Smart Materials Integration Laboratory at Penn State University, low-temperature co-fired ceramic (LTCC) material systems have been used to fabricate a number of devices for a variety of applications. This article presents an overview of the integration of the concepts and materials that we have used to achieve miniaturization and unique device function. Examples of microwave filters, metamaterial antennas, and a dielectrophoretic cell sorter will be presented, with emphasis on device modeling and design, prototype construction methods, and test results. 相似文献
42.
Alberto Doretto Francesca Bona Elisa Falasco Daniele Morandini Elena Piano Stefano Fenoglio 《河流研究与利用》2020,36(1):91-101
Droughts are affecting an increasing number of lotic ecosystems worldwide due to the combined effects of climatic and anthropogenic pressures. Unlike naturally intermittent rivers, where the drying phase is a part of the annual flow regime, water scarcity in Alpine rivers represents a relatively recent phenomenon and, therefore, a major threat for the biodiversity of these lotic ecosystems. However, Alpine stream community response to drought is still poorly investigated. Here, we assess the recovery of macroinvertebrates in two Alpine streams after a supraseasonal drought. As water returned, a total of 10 sampling sessions were carried out, and temporal patterns in diversity, density, and taxonomic composition of benthic communities, as well as in the percentage of functional feeding groups, were investigated. We found that the resistance of invertebrate communities in Alpine streams is generally low: drought markedly reduced the diversity and density of macroinvertebrates. Conversely, our results suggest that the passive dispersal by drift from the upstream river sections seems the most probable mechanism promoting the post‐drought recovery. Nevertheless, this resilience ability appears to be stream specific and influenced by intrinsic stream characteristics, including the flow permanence and distance from the nearest upstream perennial reach. This work sheds light on the ecological consequences of droughts on macroinvertebrate communities. As flow intermittency in Alpine areas is expected to intensify under current global change scenarios, results of this study provide important information to predict changes in the taxonomic composition and diversity of macroinvertebrate communities. 相似文献
43.
Adel Al Rai Elena Stojanovska Yasin Akgul Mohammad Mansoob Khan Ali Kilic Safak Yilmaz 《应用聚合物科学杂志》2021,138(7):49835
Highly porous free-standing co-poly(vinylidene fluoride)/modacrylic/SiO2 nanofibrous membrane was developed using electrically-assisted solution blow spinning method. The performance and the potential of the membrane as a lithium-ion battery separator were investigated. The addition of modacrylic enhanced the solution spinnability that resulted in defect-free membranes. Moreover, the presence of modacrylic enhanced the dimensional and thermal stabilities, while the addition of hydrophilic SiO2 nanoparticle enhanced both mechanical property and ionic conductivity. Combustion test results illustrated that the presence of modacrylic provide flame retarding property over a set of different polymeric-based membranes. Electrochemical performance results showed that the developed membrane can increase the battery capacity compared with the commercial separator. 相似文献
44.
Robustness of ISS systems to inputs with limited moving average: Application to spacecraft formations
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Esten Ingar Grøtli Elena Panteley Antoine Chaillet Jan Tommy Gravdahl 《国际强度与非线性控制杂志
》2016,26(4):816-833
》2016,26(4):816-833
We provide a theoretical framework that fits realistic challenges related to spacecraft formation with disturbances. We show that the input‐to‐state stability of such systems guarantees some robustness with respect to a class of signals with bounded average‐energy, which encompasses the typical disturbances acting on spacecraft formations. Solutions are shown to converge to the desired formation, up to an offset, which is somewhat proportional to the considered moving average of disturbances. In the presence of fast peaking perturbations, the approach provides a tighter evaluation of the disturbances' influence, which allows for the use of more parsimonious control gains. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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46.
A basic goal in property testing is to identify a minimal set of features that make a property testable. For the case when the property to be tested is membership in a binary linear error-correcting code, Alon et al. (Trans Inf Theory, 51(11):4032–4039, 2005) had conjectured that the presence of a single low-weight codeword in the dual, and “2-transitivity” of the code (i.e., the code being invariant under a 2-transitive group of permutations on the coordinates of the code) suffice to get local testability. We refute this conjecture by giving a family of error-correcting codes where the coordinates of the codewords form a large field of characteristic two, and the code is invariant under affine transformations of the domain. This class of properties was introduced by Kaufman & Sudan (STOC, 2008) as a setting where many results in algebraic property testing generalize. Our result shows a complementary virtue: This family also can be useful in producing counterexamples to natural conjectures. 相似文献
47.
Elena Baralis Andrea Bianco Tania Cerquitelli Luca Chiaraviglio Marco Mellia 《Computer Networks》2013,57(17):3300-3315
Internet measured data collected via passive measurement are analyzed to obtain localization information on nodes by clustering (i.e., grouping together) nodes that exhibit similar network path properties. Since traditional clustering algorithms fail to correctly identify clusters of homogeneous nodes, we propose the NetCluster novel framework, suited to analyze Internet measurement datasets. We show that the proposed framework correctly analyzes synthetically generated traces. Finally, we apply it to real traces collected at the access link of Politecnico di Torino campus LAN and discuss the network characteristics as seen at the vantage point. 相似文献
48.
Elena Molina Mercedes Ramos Pedro J. Martin-álvarez 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1995,201(4):331-335
Stepwise multiple linear regression (SMLR) and principal components regression (PCR) have been used to predict the percentages of cows', goats' and ewes' milk in Iberico cheese, using the results obtained by electrophoretic analysis (PAGE and IEF) of whey proteins, using standard cheeses. Similar predictions of the percentages of milks from the three species were obtained when either SMLR or PCR were applied to the electrophoretic data, i.e. the optical intensity of the electrophoretic bands (PAGE or IEF) of the whey proteins. The root mean square error of prediction in cross-validation (RMSEPCV) was lower than 4% in all cases. 相似文献
49.
Mónica Giménez‐Marqués Elena Bellido Thomas Berthelot Teresa Simón‐Yarza Tania Hidalgo Rosana Simón‐Vázquez África González‐Fernández José Avila Maria Carmen Asensio Ruxandra Gref Patrick Couvreur Christian Serre Patricia Horcajada 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(40)
Controlling the outer surface of nanometric metal–organic frameworks (nanoMOFs) and further understanding the in vivo effect of the coated material are crucial for the convenient biomedical applications of MOFs. However, in most studies, the surface modification protocol is often associated with significant toxicity and/or lack of selectivity. As an alternative, how the highly selective and general grafting GraftFast method leads, through a green and simple process, to the successful attachment of multifunctional biopolymers (polyethylene glycol (PEG) and hyaluronic acid) on the external surface of nanoMOFs is reported. In particular, effectively PEGylated iron trimesate MIL‐100(Fe) nanoparticles (NPs) exhibit suitable grafting stability and superior chemical and colloidal stability in different biofluids, while conserving full porosity and allowing the adsorption of bioactive molecules (cosmetic and antitumor agents). Furthermore, the nature of the MOF–PEG interaction is deeply investigated using high‐resolution soft X‐ray spectroscopy. Finally, a cell penetration study using the radio‐labeled antitumor agent gemcitabine monophosphate (3H‐GMP)‐loaded MIL‐100(Fe)@PEG NPs shows reduced macrophage phagocytosis, confirming a significant in vitro PEG furtiveness. 相似文献
50.
Elena Baralis Stefano Ceri Piero Fraternali Stefano Paraboschi 《Journal of Intelligent Information Systems》1996,7(2):129-149
The lack of tools for rule generation, analysis, and run-time monitoring appears one of the main obstacles to the widespreading of active database applications. This paper describes a complete tool environment for assisting the design of active rules applications; the tools were developed at Politecnico di Milano in the context of the IDEA Project, a 4-years Esprit project sponsored by the European Commission which was launched in June 1992. We describe tools for active rule generation, analysis, debugging, and browsing; rules are defined in Chimera, a conceptual design model and language for the specification of active rules applications. We also introduce a tool for mapping from Chimera into Oracle, a relational product supporting triggers.Most of the tools described in this paper are fully implemented and currently in operation (beta-testing) within the companies participating to the IDEA Project, with the exception of two of them (called Argonaut-V and Pandora), which will be completed by the end of 1996.Research presented in this paper is supported by Esprit project P6333 IDEA, and by ENEL contract VDS 1/94: Integrity Constraint Management 相似文献