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排序方式: 共有614条查询结果,搜索用时 15 毫秒
611.
Shubham Bisen Parvez Shaik Justin Jose Jamel Nebhen Ondrej Krejcar Vimal Bhatia 《International Journal of Communication Systems》2023,36(6):e5440
To achieve high data rates expected from beyond 5G communications, higher-order modulation techniques have been explored. The energy-efficient modulation technique with a high data rate has encouraged researches towards an optimum two-dimensional hexagonal-shaped constellation, namely, hexagonal quadrature amplitude modulation (HQAM). Thus, in this work, we analyze the average symbol error rate (ASER) of HQAM schemes by considering a two-user nonorthogonal multiple access (NOMA) pair. Closed-form expressions for ASER of HQAM schemes for users are derived over generalized Nakagami- fading channels. Further, for the HQAM constellation feasibility in two-user downlink NOMA systems, the power allocation criterion for the users is presented. Furthermore, the impact of modulation order of the users over the systems ASER analysis is investigated and valuable insights are drawn. 相似文献
612.
Sandeep Verma Sakshi Bhatia Sherali Zeadally Satnam Kaur 《International Journal of Communication Systems》2023,36(16):e5583
A wireless sensor network (WSN) is a network of tiny sensors deployed to collect data. These sensors are powered with batteries that have limited power. Recharging and/or replacement of these batteries, however, are not always feasible. Over the past few years, WSN applications are being deployed in diverse fields such as military, manufacturing, healthcare, agriculture, and so on. With the ever-increasing applications of WSNs, improving the energy efficiency of the WSNs still remains to be a challenge. Applying fuzzy logic to the problem of clustering exploits the uncertainty associated with the factors that affect the lifetime of these sensors and enables the development of models that would improve their performance in real-world applications. We present a comprehensive review of various fuzzy-based techniques for clustering in WSNs whose main goal is to optimize energy usage in WSNs while simultaneously improving their overall performance. 相似文献
613.
614.
Dr. Anjali Rajwar Gada Payal Vaswani Dr. Ramesh Singh Prof. Dhiraj Bhatia 《Chembiochem : a European journal of chemical biology》2023,24(7):e202200634
DNA nanocages have been explored for abilities to influence cellular behavior and functions. Recent times have seen the development of new emergent functionalities of DNA nanodevices as a class of biomaterials with an immense capacity to interface with biological systems and with vast potential in disease diagnosis and therapeutics. Being chemically robust and biocompatible in nature, DNA nanocages have been surface modified and structurally fine-tuned to find emerging applications in the field of stem-cell therapy and tissue regeneration. DNA nanocages can be used for therapeutic angiogenesis that involves the induction of blood vessel formation and can be used to treat ischemic diseases like stroke or heart failure. This work addresses the effect of DNA nanocages’ structural topology on their capacity to stimulate endothelial cell angiogenesis. We tested a panel of four DNA nanocage geometries and checked their potential on the differentiation of human umbilical vein endothelial cells (HUVECs). While different DNA nanocage geometries showed successful induction of angiogenesis and cell migration in HUVECs, tetrahedral DNA cages showed the maximum uptake and angiogenesis potential, thus indicating that not only the composition of materials, but also the 3D arrangement of ligands might play role in stimulating angiogenesis. 相似文献