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981.
982.
Wireless Networks - In this paper, we propose two cooperative spectrum sharing protocols for cognitive radio networks which consist of an automatic repeat request based primary user with a primary... 相似文献
983.
The effect of suspended CuO nanoparticles on the mass transfer to a rotating disc electrode was investigated experimentally, using the electrochemical limiting diffusion current technique. The particle volume fraction was from 0.39% to 1.94%. The rotating speed ranged from 100 to 1000 rpm, which yielded the Reynolds number between 10 and 110, based on the electrochemically active disc radius. The results showed that the addition of the suspended particles increased the limiting current and the plot of log I vs. log ω resulted in linear lines, of which slopes decreased with increasing particle volume fraction. The ratio of Sh/Sho ranged from 1 to 1.5. The Sherwood number correlation as function of the Reynolds number and the particle volume fraction was also given. 相似文献
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985.
Teodoro Sara Silva Adão Dinis Rui Gameiro Atílio 《Wireless Personal Communications》2017,96(1):799-812
Wireless Personal Communications - Channel state information at the transmitter side is an important issue for wireless communications systems, namely when precoding techniques are employed. Recent... 相似文献
986.
987.
Bahnasse Ayoub Talea Mohamed Badri Abdelmajid Louhab Fatima Ezzahraa Laafar Sara 《Telecommunication Systems》2020,73(2):155-169
Telecommunication Systems - MPLS VPN is growing in front of the other network layer tunneling technologies of the OSI model. The trend related to this technology is justified mainly by the... 相似文献
988.
Dr. Sara Morales-Reina Dr. Chandan Giri Maxime Leclercq Dr. Sonia Vela-Gallego Isabel de la Torre Dr. José R. Castón Dr. Mathieu Surin Dr. Andrés de la Escosura 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(5):1082-1090
One of the major goals in systems chemistry is to create molecular assemblies with emergent properties that are characteristic of life. An interesting approach toward this goal is based on merging different biological building blocks into synthetic systems with properties arising from the combination of their molecular components. The covalent linkage of nucleic acids (or their constituents: nucleotides, nucleosides and nucleobases) with lipids in the same hybrid molecule leads, for example, to the so-called nucleolipids. Herein, we describe nucleolipids with a very short sequence of two nucleobases per lipid, which, in combination with hydrophobic effects promoted by the lipophilic chain, allow control of the self-assembly of lipidic amphiphiles to be achieved. The present work describes a spectroscopic and microscopy study of the structural features and dynamic self-assembly of dinucleolipids that contain adenine or thymine moieties, either pure or in mixtures. This approach leads to different self-assembled nanostructures, which include spherical, rectangular and fibrillar assemblies, as a function of the sequence of nucleobases and chiral effects of the nucleolipids involved. We also show evidence that the resulting architectures can encapsulate hydrophobic molecules, revealing their potential as drug delivery vehicles or as compartments to host interesting chemistries in their interior. 相似文献
989.
A highly accurate method for simulating surfactant-covered droplets in two-dimensional Stokes flow with solid boundaries is presented. The method handles both periodic channel flows of arbitrary shape and stationary solid constrictions. A boundary integral method together with a special quadrature scheme is applied to solve the Stokes equations to high accuracy, also for closely interacting droplets. The problem is considered in a periodic setting and Ewald decompositions for the Stokeslet and stresslet are derived. Computations are accelerated using the spectral Ewald method. The time evolution is handled with a fourth-order, adaptive, implicit-explicit time-stepping scheme. The numerical method is tested through several convergence studies and other challenging examples and is shown to handle drops in close proximity both to other drops and solid objects to high accuracy. 相似文献
990.
Positivity - In this paper, we study the local ordered $$*$$ -vector spaces and their representations. We prove that each Archimedean local ordered $$*$$ -vector space, can be represented as a... 相似文献