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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   
2.
Journal of Radioanalytical and Nuclear Chemistry - This paper presents results of the development process of low-background, digital gamma-rays spectrometer equipped with Broad Energy Germanium...  相似文献   
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Nonlinear Dynamics - This paper examines the oscillations of a spherical pendulum with horizontal Lissajous excitation. The pendulum has two degrees of freedom: a rotational angle defined in the...  相似文献   
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For wide classes of locally convex spaces, in particular, for the space C p ( X ) of continuous real‐valued functions on a Tychonoff space X equipped with the pointwise topology, we characterize the existence of a fundamental bounded resolution (i.e., an increasing family of bounded sets indexed by the irrationals which swallows the bounded sets). These facts together with some results from Grothendieck's theory of ( D F ) ‐spaces have led us to introduce quasi‐ ( D F ) ‐spaces, a class of locally convex spaces containing ( D F ) ‐spaces that preserves subspaces, countable direct sums and countable products. Regular ( L M ) ‐spaces as well as their strong duals are quasi‐ ( D F ) ‐spaces. Hence the space of distributions D ( Ω ) provides a concrete example of a quasi‐ ( D F ) ‐space not being a ( D F ) ‐space. We show that C p ( X ) has a fundamental bounded resolution if and only if C p ( X ) is a quasi‐ ( D F ) ‐space if and only if the strong dual of C p ( X ) is a quasi‐ ( D F ) ‐space if and only if X is countable. If X is metrizable, then C k ( X ) is a quasi‐ ( D F ) ‐space if and only if X is a σ‐compact Polish space.  相似文献   
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Cisplatin is a drug frequently used in chemotherapy of various types of tumors due to its strong cytostatic activity against cancer cells. However, this therapy is not free from severe side effects related to the nonselective action of the drug. The solution to this problem could be the application of drug-targeted delivery systems (DTDSs). Gold nanoparticles can be used in such systems as selective drug carriers, ensuring its transportation through the bloodstream to destination tissue. The method of DTDSs analysis providing qualitative and quantitative information about the formation of this conjugation is crucial to establish the kinetics of reaction and stoichiometry of reagents, which ensures the best drug binding rate. Moreover, the status of so far proposed techniques/methods dedicated to elaborating the course of DTDSs formation is preliminary and in majority guarantee only the confirmation of drug‒carrier conjugate formation. In this paper, we demonstrate the procedures of reagents’ preparation and cisplatin‒gold nanoparticles DTDS formation, which have a significant influence on the rate and stoichiometry of the reaction. We also present the novel application of CE-ICP-MS hyphenation for effective separation and online monitoring of all components of the reaction mixture.  相似文献   
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Molecular Diversity - After the 1918 Spanish Flu pandemic caused by the H1N1 virus, the recent coronavirus disease 2019 (COVID-19) brought us to the time of serious global health catastrophe....  相似文献   
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We show for which (d,n) ∈ Z×N there exists a smooth self-map f:S2S2 so that deg(f)=d and Fix(fn) is a point.  相似文献   
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