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排序方式: 共有693条查询结果,搜索用时 15 毫秒
1.
An optimal control approach to continuous-time aggregate production planning problems is presented. The proposed approach describes the production and capacity evolution (expansion, sell and deterioration) processes in the form of differential equations with regular production, subcontracting and capacity change rates controllable on one hierarchical level. In this way, the traditional disadvantages of the two-level problem consideration (one level for strategic capacity planning and the other for production smoothing) are avoided. Analytical properties for optimal production and capacity control regimes and conditions for their changeover are derived by the maximum principle. Based on these results, an insight into the optimal behaviour of the production system is gained and a fast numerical method is developed to identify and sequence the optimal regimes for arbitrary demand profiles. A computational example illustrates the effectiveness of the approach. 相似文献
2.
Alsu Z. Malikova Anastasia S. Shcherbakova Konstantin A. Konduktorov Anastasia S. Zemskaya Alexandra A. Dalina Vladimir I. Popenko Olga G. Leonova Alexei V. Morozov Nikolay N. Kurochkin Olga A. Smirnova Sergey N. Kochetkov Maxim V. Kozlov 《International journal of molecular sciences》2021,22(9)
Recent evidence suggests that fibrotic liver injury in patients with chronic hepatitis C correlates with cellular senescence in damaged liver tissue. However, it is still unclear how senescence can affect replication of the hepatitis C virus (HCV). In this work, we report that an inhibitor of cyclin-dependent kinases 4/6, palbociclib, not only induced in hepatoma cells a pre-senescent cellular phenotype, including G1 arrest in the cell cycle, but also accelerated viral replicon multiplication. Importantly, suppression of HCV replication by direct acting antivirals (DAAs) was barely affected by pre-senescence induction, and vice versa, the antiviral activities of host-targeting agents (HTAs), such as inhibitors of human histone deacetylases (HDACi), produced a wide range of reactions—from a dramatic reduction to a noticeable increase. It is very likely that under conditions of the G1 arrest in the cell cycle, HDACi exhibit their actual antiviral potency, since their inherent anticancer activity that complicates the interpretation of test results is minimized. 相似文献
3.
The processes occurring in aprotic electrolyte on a lithium electrode in the steady state conditions and under polarization
are studied using the method of electrochemical noise characterization. The evidence of the electro-chemical noise measurements
on polarized lithium electrodes indicates that the discharge of lithium ions under cathodic polarization, as well as lithium
anodic dissolution, is localized under the passive film rather than on its surface. An increase in the polarizing current
results in local breakdown of the film; in this case, the electrochemical process emerges on the electrode surface affecting
the character of potential fluctuations. The intensity of electrochemical noise significantly increases in the course of cathodic
polarization with high currents. The reason is that lithium metal crystals, which are formed under the passive film, perforate
the film, and dendrites grow on its surface. The method shows the dependence of electrochemical noise intensity on the nature
of the electrolyte and establishes the correlation between the stability of the lithium electrode in the course of cycling
and the intensity of fluctuations. This offers an opportunity of using the method of electrochemical noise for screening organic
electrolytes for lithium batteries. 相似文献
4.
Tomaschek Fabian Arnold Denis Sering Konstantin Strauss Friedolin 《Language Resources and Evaluation》2021,55(4):1127-1140
Language Resources and Evaluation - This report presents a corpus of articulations recorded with Schlieren photography, a recording technique to visualize aeroflow dynamics for two purposes. First,... 相似文献
5.
The Differential Evolution Entirely Parallel (DEEP) method is applied to the biological data fitting problem. We introduce
a new migration scheme, in which the best member of the branch substitutes the oldest member of the next branch that provides
a high speed of the algorithm convergence. We analyze the performance and efficiency of the developed algorithm on a test
problem of finding the regulatory interactions within the network of gap genes that control the development of early Drosophila
embryo. The parameters of a set of nonlinear differential equations are determined by minimizing the total error between the
model behavior and experimental observations. The age of the individuum is defined by the number of iterations this individuum
survived without changes. We used a ring topology for the network of computational nodes. The computer codes are available
upon request. 相似文献
6.
7.
Marko Hassinen Konstantin Hyppnen Elena Trichina 《Electronic Commerce Research and Applications》2008,7(2):214-231
Payments are the locomotive behind any business domain. It has been predicted that mobile payments will become one of the most successful mobile services, and the security of payments is an important requirement. However, it is difficult to strongly authenticate mobile users remotely and provide an adequate level of non-repudiation of transactions. In this article, we argue that a nationwide public-key infrastructure supported by governmental bodies can be used in a mobile payment system. Not only does it provide strong security, but it also makes the system open to any mobile user, merchant, or financial service provider. Two payment protocols are described: one for virtual point-of-sale payments, and one for vending machine payments. We argue that such a system can be implemented using open development platforms, and its performance is adequate for enabling swift transactions. A prototype of a system which accepts virtual point-of-sale payments is implemented, and its performance and usability are evaluated. 相似文献
8.
Konstantin L. Metlov 《Journal of Low Temperature Physics》2005,139(1):207-219
No Heading Cross-tie domain wall is a complex two dimensional magnetic domain wall structure, often found experimentally in thin soft ferromagnetic films with thicknesses of about several exchange lengths. The structure of such a wall can roughly be imagined as a sequence of magnetic vortices and anti-vortices, arranged along a straight line. In this work, equilibrium energies of different one-dimensional magnetic domain wall configurations, existing in thin soft ferromagnetic films, are calculated (fully taking into account the exchange and long range dipolar interaction), based on the various classical Ritz models. They are compared to the energy of two-dimensional cross-tie domain wall, thus, estimating the region of the film thicknesses, where the cross-tie structure is the lowest energy domain wall configuration. The upper boundary of this region is estimated here for the first time. Convenient approximate analytical energy expressions in terms of elementary functions are given here both for classical and for cross-tie domain walls.PACS numbers: 75.75.+a, 75.25.+z, 75.60.–d. 相似文献
9.
Ferroelectric Materials for Microwave Tunable Applications 总被引:4,自引:0,他引:4
A.K. Tagantsev V.O. Sherman K.F. Astafiev J. Venkatesh N. Setter 《Journal of Electroceramics》2003,11(1-2):5-66
A review of the properties of ferroelectric materials that are relevant to microwave tunable devices is presented: we discuss the theory of dielectric response of tunable bulk materials and thin films; the experimental results from the literature and from own work are reviewed; the correspondence between the theoretical results and the measured properties of tunable materials is critically analyzed; nominally pure, real (defected), and composite bulk materials and thin films are addressed. In addition, techniques for characterization of tunable ferroelectrics and applications of these materials are briefly presented. 相似文献
10.
Aleksandra Ochneva Yana Zorkina Olga Abramova Olga Pavlova Valeriya Ushakova Anna Morozova Eugene Zubkov Konstantin Pavlov Olga Gurina Vladimir Chekhonin 《International journal of molecular sciences》2022,23(22)
Mental disorders represent common brain diseases characterized by substantial impairments of social and cognitive functions. The neurobiological causes and mechanisms of psychopathologies still have not been definitively determined. Various forms of brain proteinopathies, which include a disruption of protein conformations and the formation of protein aggregates in brain tissues, may be a possible cause behind the development of psychiatric disorders. Proteinopathies are known to be the main cause of neurodegeneration, but much less attention is given to the role of protein impairments in psychiatric disorders’ pathogenesis, such as depression and schizophrenia. For this reason, the aim of this review was to discuss the potential contribution of protein illnesses in the development of psychopathologies. The first part of the review describes the possible mechanisms of disruption to protein folding and aggregation in the cell: endoplasmic reticulum stress, dysfunction of chaperone proteins, altered mitochondrial function, and impaired autophagy processes. The second part of the review addresses the known proteins whose aggregation in brain tissue has been observed in psychiatric disorders (amyloid, tau protein, α-synuclein, DISC-1, disbindin-1, CRMP1, SNAP25, TRIOBP, NPAS3, GluA1, FABP, and ankyrin-G). 相似文献