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排序方式: 共有1217条查询结果,搜索用时 34 毫秒
1.
Dariusz Marek Adam Domaski Joanna Domaska Jakub Szygua Tadeusz Czachrski Jerzy Klamka 《Entropy (Basel, Switzerland)》2021,23(5)
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 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.
Computational Management Science - In this paper, a new approximation method for a characterization of (weak) Pareto solutions in some class of nonconvex differentiable multiobjective programming... 相似文献
3.
4OR - In this paper, the class of differentiable semi-infinite multiobjective programming problems with vanishing constraints is considered. Both Karush–Kuhn–Tucker necessary optimality... 相似文献
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5.
Dr. Mateusz Janeta Prof. Tadeusz Lis Prof. Sławomir Szafert 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(60):13686-13697
In the present research, the synthesis, spectroscopic characterization, and structural investigations of a unique ZnII complex of imine-functionalized polyhedral oligomeric silsesquioxane (POSS) is designed, and hereby described, as a catalyst for the synthesis of cyclic carbonates from epoxides and CO2. The uncommon features of the designed catalytic system is the elimination of the need for a high pressure of CO2 and the significant shortening of reaction times commonly associated with such difficult transformations like that of styrene oxide to styrene carbonate. Our studies have shown that imine-POSS is able to chelate metal ions like ZnII to form a unique coordination complex. The silsesquioxane core and the hindrance of the side arms (their steric effect) influence the construction process of the homoleptic Zn4@POSS-1 complex. The compound was characterized in solution by NMR (1H, 13C, 29Si), ESI-MS, UV/Vis spectroscopy and in the solid state by thermogravimetric/differential thermal analysis (TG-DTA), elemental analysis, diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), cross-polarization magic angle spinning (CP MAS) NMR (13C, 29Si) spectroscopy, and X-ray crystallography. 相似文献
6.
Martowicz Adam Bryła Jakub Staszewski Wieslaw J. Ruzzene Massimo Uhl Tadeusz 《Nonlinear dynamics》2019,97(3):1911-1935
Nonlinear Dynamics - The work is primarily devoted to the peridynamic model elaborated for a solid body made of shape memory alloys (SMAs). The superelasticity effect is taken into consideration as... 相似文献
7.
JPC – Journal of Planar Chromatography – Modern TLC - 相似文献
8.
Roksana Kordala-Markiewicz Hubert Rodak Bartosz Markiewicz Filip Walkiewicz Agata Sznajdrowska Katarzyna Materna Katarzyna Marcinkowska Tadeusz Praczyk Juliusz Pernak 《Tetrahedron》2014
Ammonium ionic liquids with the 4-chloro-2-methylphenoxyacetate anion were synthesized and characterized. Physicochemical properties, such as thermal stability, phase transition temperatures, viscosity, density, refractive index, as well as surface activity and herbicidal activity were determined. Improved physicochemical properties suggest a reduced environmental impact of newly formed group of herbicidal ionic liquids (HILs). HILs with a longer substituent can be characterized with better herbicidal activity in comparison with commercial products. 相似文献
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10.
Tomasz Rojek Tadeusz Lis Ewa Matczak‐Jon 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(7):593-597
The asymmetric unit of the title salt, C12H24N+·C2H2BrO2−, contains a dicyclohexylammonium cation connected to a bromoacetate anion by means of an N—H...O hydrogen bond. In the crystal, the ion pairs assemble via N—H...O interactions, forming zigzag infinite chains parallel to the c axis with the (...H—N—H...O—C—O...)n motif that is considered to be a prerequisite for ensuring gelation properties of secondary ammonium monocarboxylate salts. The title salt was characterized by FT–IR, X‐ray powder diffraction (XRPD), TG–DTA and 1H NMR spectroscopy in solution. Gelation experiments revealed that dicyclohexylammonium bromoacetate forms molecular gels with dimethylformamide and dimethyl sulfoxide. Scanning electron microscopy (SEM) was used to reveal morphological features of dried gels. 相似文献