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An assignment walk through 3D NMR spectrum
2009 IEEE Symposium on Computational Intelligence in Bioinformatics and Computational Biology, 2009Nuclear Magnetic Resonance spectroscopy is an important technique to study structures of biomolecules. While it is possible to use two-dimensional experiments to determine RNA structures, multi-dimensional experiments ensure a better distribution of signals providing a clearer view of the intra- as well as inter-molecular correlations.
Marta Szachniuk +3 more
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Assignments in the electronic spectrum of UF6
The Journal of Chemical Physics, 1976The absorption spectrum of gaseous UF6 was recorded from 1200–4200 Å (83 300–23 800 cm−1). Eight electronic transitions were observed with intensities ranging from 8–20 000 1/mole⋅cm. Based on correlations between this spectrum and those of UF6−, UCl6−, MoF6, and WF6 and the photoelectron spectrum of UF6, the experimental spectrum was assigned.
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Routing and Spectrum Assignment in Spectrum Flexible Transparent Optical Networks
2014In this paper the heuristic algorithm for the selection lightpaths in flexible transparent optical networks has been presented. The considered problem of routing and spectrum assignment (RSA) takes into consideration minimizing the length of the transmission distance under spectrum continuity constraints and relationship between the traffic bitrates ...
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Fragmentation aware routing and spectrum assignment algorithm
2014 IEEE International Conference on Communications (ICC), 2014In flex-grid (elastic) networks, the spectrum can be allocated at a much finer granularity than it can be allocated in WDM networks. However, the dynamic establishment and tear down of lightpaths yields to the fragmentation of the spectrum with consequent increase in blocking of requests for connection establishment.
Pedro M. Moura +2 more
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Impact of Constraints on the Complexity of Dynamic Spectrum Assignment
IEEE GLOBECOM 2008 - 2008 IEEE Global Telecommunications Conference, 2008In this paper we study the complexity of spectrum assignment problems in cognitive radio networks (CRNs) in the presence of several constraints. Although optimal spectrum assignment for secondary transmissions in CRNs is generally believed to be NP complete, the impact of fairness and link quality constraints on the hardness of the problem is not well ...
Chetan Nanjunda Mathur +3 more
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Frequency Assignment and Spectrum Conservation
2009This chapter contains sections titled: Introduction Frequency Allocation and Frequency Assignment Modulation Techniques Spectrum Conservation Spectrum Conservation: Concluding Comments References ...
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On the Distance Spectrum Assignment in Elastic Optical Networks
IEEE/ACM Transactions on Networking, 2017In elastic optical networks, two lightpaths sharing common fiber links might have to be isolated in the spectrum domain with a proper guard-band to prevent crosstalk and/or reduce physical-layer security threats. Meanwhile, the actual requirements on guard-band sizes can vary for different lightpath pairs, because of various reasons. Therefore, in this
Haitao Wu +3 more
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Cognitive radio spectrum assignment and handoff decision
2013 IEEE 24th Annual International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC), 2013Spectrum management task is difficult to achieve in a dynamic and distributed network where cognitive radio users may only make local decision and have to react to the environment changes. In this paper, we describe a novel spectrum management approach for a cognitive radio ad-hoc network.
Trigui, Emna +2 more
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Autonomous Spectrum Assignment of White Space Devices
2018White-space spectrum has temporal and spatial variations, and fragmentation, making the spectrum assignment for devices in this space challenging. In this paper, we propose an autonomous agent model for spectrum assignment of white space devices at a given location.
Chaitali Diwan +2 more
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