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951.
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IAMMAC: an interference‐aware multichannel MAC protocol for wireless sensor–actor networks
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Jagadeesh Kakarla Banshidhar Majhi Ramesh Babu Battula 《International Journal of Communication Systems》2016,29(4):801-822
In this paper, we discuss an interference aware multichannel MAC (IAMMAC) protocol assign channels for communication in wireless sensor‐actor networks. An actor acts as a cluster head for k‐hop sensors and computes the shortest path for all the sensors. Then, the actor partitions the cluster into multiple subtrees and assigns a noninterference channel to each subtree. The actor 1‐hop sensors are represented as relay nodes. The actor selects a relay node as a backup cluster head (BCH) based on the residual energy and node degree. After selecting a BCH from the relay nodes, the actor broadcast this information to the remaining relay nodes using the common control channel. The relay sensors use the same channel of BCH to communicate with it. However, the other cluster members do not change their data channel. Further, interference‐aware and throughput‐aware multichannel MAC protocol is also proposed for actor–actor coordination. The performance of the proposed IAMMAC protocol is analyzed using standard network parameters such as packet delivery ratio, goodput, end‐to‐end delay, and energy dissipation in the network. The obtained simulation results indicate that the IAMMAC protocol has superior performance as compared with the existing MAC protocols. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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In this work, two-channel perfect reconstruction quadrature mirror filter (QMF) bank has been proposed based on the prototype filter using windowing method. A novel window function based on logarithmic function along with the spline function is utilized for the design of prototype filter. The proposed window has a variable parameter ‘\(\alpha \)’, which varies the peak side lobe level and rate of fall-off side lobe level which in turn affects the peak reconstruction error (PRE) and amplitude distortion (\(e_{am}\)) of the QMF bank . The transition width of the prototype is controlled by the spline function using the parameter ‘\(\mu \)’. The perfect reconstruction condition is satisfied by setting the cutoff frequency (\(\omega _{c}\)) of the prototype low-pass filter at ‘\(\pi /2\)’. The performance of the proposed design method has been evaluated in terms of mean square error in the pass band, mean square error in the stop band, first side lobe attenuation (\(A_{1}\)), peak reconstruction error (PRE) and amplitude error (\(e_{am}\)) for different values of ‘\(\alpha \)’ and ‘\(\mu \)’. The results are provided and compared with the existing methods. 相似文献
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The study of electromagnetohydrodynamics (EMHD) of non-Newtonian fluid plays a significant role for optical design, thermal management of electronic components, and various operations of microfluidic devices. The use of parallel geometry is seen in the circulatory system, extrusion process, and respiratory system. By considering various practical applications, in the current study, the Poiseuille flow of an incompressible Casson liquid between the plates is investigated. The effects of MHD, Joule heating, thermal radiation, modified Darcy's law, and chemical reaction have been taken into account. The dimensional governing equations have been converted into dimensionless equations with pertinent nondimensional quantities. The resulting system of nondimensional system of equations has been analytically solved with nondimensional slip boundary conditions. The graphical results have been displayed with various fluid flow parameters. From the current study, it is concluded that the influence of Darcy number and Casson fluid parameter enhances the velocity profile, but the concentration declines with the enhancement of Casson fluid parameter. The radiation parameter and Prandtl number suppress the temperature profile. 相似文献
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Multimedia Tools and Applications - In theaters and the filmmaking industry, video streams, images, audio streams and scalar data are commonly used. In these fields, one of the most important... 相似文献
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Vallée Till Rakesh Hossahalli Ramesh Tannert Thomas 《Holz als Roh- und Werkstoff》2022,80(5):1041-1055
European Journal of Wood and Wood Products - Timber engineering is currently crossing new frontiers in terms of performance, as illustrated by the increasing number of high-rise buildings. This has... 相似文献
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Le Zhang Prashanthi Ramesh Maxime Steinmetz Jan Paul Medema 《International journal of molecular sciences》2021,22(8)
Colorectal cancer (CRC) is a heterogeneous disease, which in part explains the differential response to chemotherapy observed in the clinic. BH3 mimetics, which target anti-apoptotic BCL-2 family members, have shown potential in the treatment of hematological malignancies and offer promise for the treatment of solid tumors as well. To gain a comprehensive understanding of the response to BH3 mimetics in CRC and the underlying molecular factors predicting sensitivity, we screened a panel of CRC cell lines with four BH3 mimetics targeting distinct anti-apoptotic BCL-2 proteins. Treatment with compounds alone and in combination revealed potent efficacy of combined MCL-1 and BCL-XL inhibition in inducing CRC cell death, irrespective of molecular features. Importantly, expression of the anti-apoptotic protein target of BH3 mimetics on its own did not predict sensitivity. However, the analysis did identify consensus molecular subtype (CMS) specific response patterns, such as higher resistance to single and combined BCL-2 and MCL-1 inhibition in CMS2 cell lines. Furthermore, analysis of mutation status revealed that KRAS mutant cell lines were more resistant to MCL-1 inhibition. Conclusively, we find that CRC cell lines presented with distinct responses to BH3 mimetics that can in part be predicted by their CMS profile and KRAS/BRAF mutations. Overall, almost all CRC lines share sensitivity in the nanomolar range to combined MCL-1 and BCL-XL targeting suggesting that this would be the preferred approach to target these cancers. 相似文献