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1.
In this article, a way to employ the diffusion approximation to model interplay between TCP and UDP flows is presented. In order to control traffic congestion, an environment of IP routers applying AQM (Active Queue Management) algorithms has been introduced. Furthermore, the impact of the fractional controller PIγ and its parameters on the transport protocols is investigated. The controller has been elaborated in accordance with the control theory. The TCP and UDP flows are transmitted simultaneously and are mutually independent. Only the TCP is controlled by the AQM algorithm. Our diffusion model allows a single TCP or UDP flow to start or end at any time, which distinguishes it from those previously described in the literature.  相似文献   
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Journal of Optimization Theory and Applications - We consider a distributionally robust formulation of stochastic optimization problems arising in statistical learning, where robustness is with...  相似文献   
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Journal of Solid State Electrochemistry - A methodology for electrochemical preparation of nickel layers intended to be used as targets for charged particle accelerators is proposed. The goal is to...  相似文献   
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Journal of Thermal Analysis and Calorimetry - The results of studies of physiological fluids by differential scanning calorimetry (DSC) for the purpose of diagnosis and monitoring of diseases are...  相似文献   
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Photostability of an antidepressant agomelatine under the simulated solar radiation was studied. Quantitative and qualitative analysis of this process was performed with the use of UHPLC-DAD system coupled with a high resolution hybrid ESI-Q-TOF mass spectrometer. In contrast to the foregoing studies agomelatine turned out to be relatively photolabile compound. During the experiment six transformation products were formed, and their structures were elucidated on the basis of MS/MS fragmentation spectra. Four of these photoproducts were found to be a result of aromatic and aliphatic hydroxylation. Additionally, identified products were submitted to the in silico toxicity evaluation, which showed that some of them could be more mutagenic or toxic to rodents than the parent compound.  相似文献   
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The mechanism of lithium insertion that occurs in an iron oxyfluoride sample with a hexagonal–tungsten–bronze (HTB)-type structure was investigated by the pair distribution function. This study reveals that upon lithiation, the HTB framework collapses to yield disordered rutile and rock salt phases followed by a conversion reaction of the fluoride phase toward lithium fluoride and nanometer-sized metallic iron. The occurrence of anionic vacancies in the pristine framework was shown to strongly impact the electrochemical activity, that is, the reversible capacity scales with the content of anionic vacancies. Similar to FeOF-type electrodes, upon de-lithiation, a disordered rutile phase forms, showing that the anionic chemistry dictates the atomic arrangement of the re-oxidized phase. Finally, it was shown that the nanoscaling and structural rearrangement induced by the conversion reaction allow the in situ formation of new electrode materials with enhanced electrochemical properties.  相似文献   
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