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61.
Andrea Bettidi Antonio Cetronio Walter Ciccognani Marco De Dominicis Claudio Lanzieri Ernesto Limiti Antonio Manna Marco Peroni Claudio Proietti Paolo Romanini 《国际射频与微波计算机辅助工程杂志》2009,19(5):598-606
In this article, the design, fabrication, and on‐wafer test of X‐Band and 2–18 GHz wideband high‐power SPDT MMIC switches in AlGaN/GaN technology are presented. The switches have demonstrated state‐of‐the‐art performance and RF fabrication yield better than 65%. Linear and power measurements for different control voltages have been reported and an explanation of the dependence of the power performances on the control voltage is given. In particular, the X‐band switch exhibits a 0.4 dB compression level at 10 GHz when driven by a 38 dBm input signal. The wideband switch shows a compression level of 1 dB at an input drive higher than 38 dBm across the entire bandwidth. © 2009 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2009. 相似文献
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This paper describes the development of a system for measuring surface coordinates (commonly known as "shape measurements") which is able to give the temporal evolution of the position of the tire sidewall in transient conditions (such as during braking, when there are potholes or when the road surface is uneven) which may or may not be reproducible. The system is based on the well-known technique of projecting and observing structured light using a digital camera with an optical axis which is slanted with respect to the axis of the projector. The transient nature of the phenomenon has led to the development of specific innovative solutions as regards image processing algorithms. This paper briefly describes the components which make up the measuring system and presents the results of the measurements carried out on the drum bench. It then analyses the performance of the measuring system and the sources of uncertainty which led to the development of the system for a specific dynamic application: impact with an obstacle (cleat test). The measuring system guaranteed a measurement uncertainty of 0.28 mm along the Z axis (the axial direction of the tire) with a measurement range of 250(X) x 80(Y) x 25(Z) mm(3), with the tire rolling at a speed of up to 30 km/h. 相似文献
63.
Influence of religiosity and spiritual coping on health‐related quality of life in Saudi haemodialysis patients 下载免费PDF全文
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Unraveling Unprecedented Charge Carrier Mobility through Structure Property Relationship of Four Isomers of Didodecyl[1]benzothieno[3,2‐b][1]benzothiophene 下载免费PDF全文
Yusuke Tsutsui Guillaume Schweicher Basab Chattopadhyay Tsuneaki Sakurai Jean‐Baptiste Arlin Christian Ruzié Almaz Aliev Artur Ciesielski Alan R. Kennedy Vincent Lemaur Yoann Olivier Rachid Hadji Lionel Sanguinet Frédéric Castet Silvio Osella Dmytro Dudenko David Beljonne Jérôme Cornil Paolo Samorì Shu Seki Yves H. Geerts 《Advanced materials (Deerfield Beach, Fla.)》2016,28(33):7106-7114
68.
Romain Carron Enrico Avancini Thomas Feurer Benjamin Bissig Paolo A. Losio Renato Figi 《Science and Technology of Advanced Materials》2018,19(1):396-410
Cu(In,Ga)Se2-based solar cells have reached efficiencies close to 23%. Further knowledge-driven improvements require accurate determination of the material properties. Here, we present refractive indices for all layers in Cu(In,Ga)Se2 solar cells with high efficiency. The optical bandgap of Cu(In,Ga)Se2 does not depend on the Cu content in the explored composition range, while the absorption coefficient value is primarily determined by the Cu content. An expression for the absorption spectrum is proposed, with Ga and Cu compositions as parameters. This set of parameters allows accurate device simulations to understand remaining absorption and carrier collection losses and develop strategies to improve performances. 相似文献
69.
Paolo Fortugno Claudia-Francisca López-Cámara Jan Patrick Kruse Mohaned Hammad Hartmut Wiggers 《Advanced Engineering Materials》2023,25(20):2300679
This study introduces a novel gas-phase method for the synthesis of mesoporous silica nanoparticles (MSNs). The method is a two-step templating approach by first forming silicon-coated carbon structures in a hybrid microwave-plasma/hot-wall reactor followed by an annealing step to produce mesoporous silica with distinct nanostructure and porosity. Two different (sacrificial) carbonaceous templates have been prepared (plasma reactor) and coated (hot-wall reactor), 2D few-layer graphene (FLG) flakes and soot-like fractal aggregates. Results show that the wall thickness of the porous silica structures can be adjusted by changing the concentration of the silicon precursor (monosilane). High monosilane concentrations, however, result in solid silica particles after annealing. Using soot-like particle templates permitted to control of the shell thickness of the hollow porous particles, while the FLG template results in ultrathin silica sheets after heat treatment. The pore volume and specific surface area increase up to 263 m2 g−1 and 0.6 cm3 g−1, respectively, by the formation of hollow porous particles. An adsorption study on carbamazepine reveals up to ≈86% removal. The gas-phase aerosol-based template method presented here offers scalability and versatility, and it is capable of producing MSNs with a controlled structure and porosity by modifying the carbonaceous templates. 相似文献
70.
In thedynamic dictionary matchingproblem, a dictionaryDcontains a set of patterns that can change over time under insertion and deletion of individual patterns. Given an arbitrary textT, we must efficiently list all the dictionary patterns that occur at each text position. We investigate the I/O complexity of this problem for a large dictionary that must be stored in external storage devices. By following a completely new approach, we devise an efficient solution which is based upon the SB-tree data structure (P. Ferragina and R. Grossi, 1995,in“Proc. ACM Symposium on Theory of Computing,” pp. 693–702), and a novel notion of certificate for the dictionary matching problem. Our data structure can be adapted to efficiently work in main memory and to solve other problems, thus providing a new insight into the nature of the dictionary matching problem. 相似文献