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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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The trends of the future electronic devices should be miniaturized,flexible,stable,portable,light,and highly integrated.Although flexible electronic products(i.e.,flexible display products[1-3],batteries[4,5],cell phones[6])have been commercially available recently,which represents the starting of a new era in electronics,these progresses are still in their infancy and more efforts are required to boom their multifunction and speed up their marketization from lab.Considering their low-cost and mass-productive synthesis technologies,rich species,high performances,and especially,the excellent flexibility and stability,organic materials(insulating,conductive and semiconducting)have triggered the tide of the development of"plastic electronics",especially in transistors,an indispensable logic device in these logic-control based devices(i.e.,intelligent electronics).  相似文献   
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Annals of the Institute of Statistical Mathematics - In this paper, a model averaging approach is developed for the linear regression models with response missing at random. It is shown that the...  相似文献   
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Zhan  Yang  Dang  Chuangyin 《Mathematical Programming》2021,190(1-2):585-613
Mathematical Programming - In the general equilibrium with incomplete asset markets (GEI) model, the excess demand functions are typically not continuous at the prices for which the assets have...  相似文献   
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Cheung  Yun Kuen  Cole  Richard  Tao  Yixin 《Mathematical Programming》2021,190(1-2):615-677
Mathematical Programming - We seek tight bounds on the viable parallelism in asynchronous implementations of coordinate descent that achieves linear speedup. We focus on asynchronous coordinate...  相似文献   
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In this work, we studied the magnetic properties of a regularly tetrahedral molecule made of four spin-½, interconnected by exchange. For this purpose, we used the Heisenberg model and performed an exact resolution. In the case of a ferromagnetic coupling among the spins, the system orders itself under a magnetic field without displaying any net spontaneous magnetization. It behaves as a high spin-2 unique magnet.Under antiferromagnetic exchange, some exotic behaviour has been revealed due to the frustration governing the spin edifice. Thus, the magnetization is quantized into plateaus, which are separated by quantum phase transitions. In particular, we have argued the possibility of a quantum spin liquid (QSL) state that can occur at low temperature.This contribution intends mainly to bring single-molecular magnets to the front line of innovative nanoscale applications.  相似文献   
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