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Katalin Balla Galina A. Kurina Roswitha März 《Journal of Dynamical and Control Systems》2006,12(3):289-311
The index of DAE systems arising from linear quadratic optimal control problems is considered. Necessary and sufficient conditions
ensuring regularity with tractability index one are proved. Then, it is shown that if the control problem DAE is regular with
index one and if the leading term of the DAE to be controlled is given by one full-column-rank and one full-row-rank matrix,
then it has a Hamiltonian inherent explicit ODE. For problems with regular index zero or index one DAEs to be controlled,
the DAE of the control problem is shown to be regular with tractability index one or three, depending on whether the control
coefficient R is singular.
2000 Mathematics Subject Classification.
49N10, 49J15, 34A09.
Supported by the DFG research center MATHEON in Berlin. This work was partially
supported by the Russian Fundamental Research Foundation Project Nos. 02-01-00351
and 06-01-00296. 相似文献
75.
Some of the modern electronic and optoelectronic devices exploit ferrofluids contained in narrow gaps between two material plates. When the width of the gap becomes below a micrometer, the boundary plates are subjected to the Casimir force arising from the zero-point and thermal fluctuations of the electromagnetic field. These forces should be taken into account in microdevices with the dimensions decreased to below a micrometer. In this paper, we review recently performed calculations of the attractive Casimir pressure in three-layer systems containing a ferrofluid. We also find the ferrofluidic system where the Casimir pressure is repulsive. This result is obtained in the framework of the fundamental Lifshitz theory of van der Waals and Casimir forces. The conclusion is made that enhanced repulsion due to the presence of a ferrofluid may prevent from sticking of closely spaced elements of a microdevice. 相似文献
76.
Anastasiya N. Mikhailova Galina P. Kayukova Igor P. Kosachev Irina I. Vandyukova Alexey V. Vakhin Georgy A. Batalin 《Petroleum Science and Technology》2018,36(17):1382-1388
Character of conversion of organic matter from Domanic rocks of Pervomaiskoye field (Tatarstan) of Semiluki horizon of upper Devonian deposits in the hydrothermal-catalytic system at temperature of 300?°C in carbon dioxide medium was studied with the application of complex of oil-soluble precursors of catalysts containing Fe, Co, and Cu. In presence of catalysts complex, content of organic extract increases, in which content of hydrocarbon fractions, saturated and aromatic hydrocarbons, increases 1.5 times, while resins content decreases by two times. As result of kerogen destruction in products of experiments, the content of asphaltenes and carbonaceous substances such as carbenes and carboides increase. 相似文献
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78.
Alexander A. Khassin Anatoly G. Sipatrov Galina K. Chermashetseva Tamara M. Yurieva Valentin N. Parmon 《Topics in Catalysis》2005,32(1-2):39-46
The Fischer–Tropsch synthesis using a contactor membrane reactor was studied varying pore size distribution parameters and membrane geometry. These parameters are responsible for the magnitude of the diffusion constrains and, therefore, correlate with the FTS process productivity and selectivity. The nature of the observed correlations is discussed. 相似文献
79.
E.?A.?Erin V.?N.?MomotovEmail author A.?A.?Baranov L.?V.?Nagaitseva Yu.?S.?Konovalova Yu.?A.?Galina 《Radiochemistry》2017,59(1):58-64
Extraction-chromatographic properties of LN-B200-S sorbent based on di-2-ethylhexyl hydrogen phosphate were studied. The equilibrium distribution coefficients of Am in the sorbent–HNO3 system, the total exchange capacity, and the capacity to breakthrough were determined. The influence of the absorbed dose on the above parameters was examined. The suggested extraction-chromatographic system was tested with a real solution of spent nuclear fuel from an RBMK-1000 reactor as applied to the recovery of the Am–Cm–Nd fraction. 相似文献
80.
Poly(hydroxybutyrate‐co‐hydroxyvalerate) and bovine serum albumin blend prepared by electrospinning 下载免费PDF全文
Elizaveta R. Pavlova Dmitry V. Bagrov Maria N. Kopitsyna Dmitry A. Shchelokov Anton P. Bonartsev Irina I. Zharkova Tatiana K. Mahina Vera L. Myshkina Galina A. Bonartseva Konstantin V. Shaitan Dmitry V. Klinov 《应用聚合物科学杂志》2017,134(29)
Electrospinning is a method for the preparation of nanosized polymer fibers. Here, electrospinning is used to prepare a blend of a polyester, poly(hydroxybutyrate‐co‐hydroxyvalerate) (PHBV), and a globular protein, bovine serum albumin (BSA). The electrospun blend film is compared with a solution‐cast blend film and with single‐component electrospun films made of PHBV and BSA. In the electrospun blend films, BSA manifests itself as flat ribbons and a fine network formed from fibers less than 50 nm in diameter. The dissolution rate of BSA from the electrospun blended film is lower than from the solution‐cast one. The films are characterized using scanning electron microscopy, differential scanning calorimetry, and contact‐angle measurements. The obtained PHBV+BSA blend films have several emergent properties: a slow BSA dissolution rate, a fine BSA network, and unusual thermal behavior. Thus, the PHBV+BSA blend films introduce a new class of polymer–protein blends. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45090. 相似文献