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1.
Summary The synthesis is reported of copolymers of styrene with methacrylic acid and of methyl methacrylate with methacrylic acid by radical copolymerization, of copolymers of methyl methacrylate with methacrylic acid by partial alkaline hydrolysis of poly(methyl methacrylate), and of block copolymers of styrene with methacrylic acid. Modified titration curves of all these copolymers were recorded in water and water-ethanol solutions. In a solution containing 50 mass.% ethanol, only small differences could be observed between the potentiometric behaviour of the individual copolymers and polymethacrylic acid. Also, there were no essential differences in any of the solvents used between the potentiometric behaviour of block copolymers of styrene with methacrylic acid, on the one hand, and polymethacrylic acid, on the other. On the contrary, maxima and minima were always observed on the modified titration curves of statistical copolymers with a higher content of the hydrophobic comonomer in solutions with a high water content. Thus, using the modified titration curves, it is possible to decide whether a given copolymer is of the block or statistical type. 相似文献
2.
André Stork Clemens-August Thole Stanislav Klimenko Igor Nikitin Lialia Nikitina Yuri Astakhov 《The Visual computer》2008,24(11):947-953
One of the important tasks in Mechanical Engineering is to increase the safety of the vehicle and decrease its production
costs. This task is typically solved by means of Multiobjective Optimization, which formulates the problem as a mapping from
the space of design variables to the space of target criteria and tries to find an optimal region in these multidimensional
spaces. Due to high computational costs of numerical simulations, the sampling of this mapping is usually very sparse and
scattered. Combining design of experiments methods, metamodeling, new interpolation schemes and innovative graphics methods,
we enable the user to interact with simulation parameters, optimization criteria, and come to a new interpolated crash result
within seconds. We denote this approach as Simulated Reality, a new concept for the interplay between simulation, optimization
and interactive visualization. In this paper we show the application of Simulated Reality for solution of real life car design
optimization problems.
相似文献
Lialia NikitinaEmail: |
3.
4.
Microstructure,Phase Composition,and Thermal Stability of Two Zirconium Alloys Subjected to High‐Pressure Torsion at Different Temperatures 下载免费PDF全文
Stanislav. O. Rogachev Sergey A. Nikulin Andrey B. Rozhnov Mikhail V. Gorshenkov 《Advanced Engineering Materials》2018,20(9)
5.
Matej Perše Author Vitae Matej Kristan Author Vitae Author Vitae Gašper Muši? Author Vitae Author Vitae Stanislav Kova?i? Author Vitae 《Pattern recognition》2010,43(4):1491-1501
This paper presents the use of place/transition petri nets (PNs) for the recognition and evaluation of complex multi-agent activities. The PNs were built automatically from the activity templates that are routinely used by experts to encode domain-specific knowledge. The PNs were built in such a way that they encoded the complex temporal relations between the individual activity actions. We extended the original PN formalism to handle the propagation of evidence using net tokens. The evaluation of the spatial and temporal properties of the actions was carried out using trajectory-based action detectors and probabilistic models of the action durations. The presented approach was evaluated using several examples of real basketball activities. The obtained experimental results suggest that this approach can be used to determine the type of activity that a team has performed as well as the stage at which the activity ended. 相似文献
6.
We study dynamic routing in store-and-forward packet networks where each network link has bounded buffer capacity for receiving
incoming packets and is capable of transmitting a fixed number of packets per unit of time. At any moment in time, packets
are injected at various network nodes with each packet specifying its destination node. The goal is to maximize the throughput, defined as the number of packets delivered to their destinations.
In this paper, we make some progress on throughput maximization in various network topologies. Let n and m denote the number of nodes and links in the network, respectively. For line networks, we show that Nearest-to-Go (NTG), a
natural distributed greedy algorithm, is
-competitive, essentially matching a known
lower bound on the performance of any greedy algorithm. We also show that if we allow the online routing algorithm to make centralized decisions, there is a randomized
polylog(n)-competitive algorithm for line networks as well as for rooted tree networks, where each packet is destined for the root
of the tree. For grid graphs, we show that NTG has a competitive ratio of
while no greedy algorithm can achieve a ratio better than
. Finally, for arbitrary network topologies, we show that NTG is
-competitive, improving upon an earlier bound of O(mn).
An extended abstract appeared in the Proceedings of the 8th Workshop on Approximation Algorithms for Combinatorial Optimization Problems, APPROX 2005, Berkeley, CA, USA, pp. 1–13, Lecture Notes in Computer Science, vol. 1741, Springer, Berlin.
S. Angelov is supported in part by NSF Career Award CCR-0093117, NSF Award ITR 0205456 and NIGMS Award 1-P20-GM-6912-1.
S. Khanna is supported in part by an NSF Career Award CCR-0093117, NSF Award CCF-0429836, and a US-Israel Binational Science
Foundation Grant.
K. Kunal is supported in part by an NSF Career Award CCR-0093117 and NSF Award CCF-0429836. 相似文献
7.
Stanislav S. Lazarev Ulyana V. Shevchenko Vyacheslav A. Dyachuk Ilya G. Vyatchin 《International journal of molecular sciences》2022,23(14)
We describe the development of a preparative method to isolate molluscan catch muscle, calponin. This method is based on the ability of calponin to interact with actin in a temperature-dependent manner. After extracting thin filaments, as previously described, the extract was ultracentrifuged at 2 °C. While other surface proteins of thin filaments co-precipitated with actin, calponin, along with some minor contaminants, remained in the supernatant. Calponin was purified through cation-exchange chromatography. The yield of pure protein was four-fold higher than that achieved through high-temperature extraction. To evaluate functionally isolated proteins, we determined the effect of calponin on Mg2+-ATPase activity of hybrid and non-hybrid actomyosin. The degree of ATPase inhibition was consistent with previously published data but strongly dependent on the environmental conditions and source of actin and myosin used. Furthermore, at low concentrations, calponin could induce the ATPase activity of hybrid actomyosin. This result was consistent with data indicating that calponin can modulate actin conformation to increase the relative content of “switched on” actin monomers in thin filaments. We assume that calponin obtained by the isolation method proposed herein is a fully functional protein that can both inhibit and induce the ATPase activity. 相似文献
8.
Henrik Peisker Lars Heepe Alexander E. Kovalev Stanislav N. Gorb 《Journal of the Royal Society Interface》2014,11(99)
Wet adhesive systems of insects strongly rely for their function on the formation of capillary bridges with the substrate. Studies on the chemical composition and evaporation dynamics of tarsal secretions strongly suggest a difference in chemistry of secretion in beetles and flies, both possessing hairy attachment devices. This difference is assumed to influence the viscosity of the secretion. Here, we applied a microrheological technique, based on the immersion of nanometric beads in the collected tarsal footprints, to estimate secretion viscosity in a beetle (Coccinella septempunctata) and a fly (Calliphora vicina). Both species studied possess distinct differences in viscosity, the median of which was calculated as 21.8 and 10.9 mPa s, respectively. We further present an approximate theoretical model to calculate the contact formation time of spatula-like terminal contact elements using the viscosity data of the covering fluid. The estimated contact formation time is proportional to the tarsal secretion viscosity and to the square of the contact radius of the contact element. 相似文献
9.
The exhibit 10 Short Films About Fog, which was part of the Data & Matter Exhibition at Palazzo Bembo during the Venice Architecture Biennale in 2018, documents and expands experiments into the relationship between fog, textiles, and air. The project sought to probe whether the otherwise formless phenomena of fog could be explicitly formed, and how it might assume structures and textures. By revealing the characteristics of fog that fascinate us, yet are latent, the short films also transform the phenomena through magnification, thereby amplifying inherent behaviors and qualities. 相似文献