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1.
Optimization and Engineering - 相似文献
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The present study was designed to determine if spinal calcium channels, calmodulin, and calcium/calmodulin-dependent protein kinase II were involved in the production of antinociception induced by cold water swimming stress (CWSS). The effects of intrathecal (i.t.) injection of nimodipine, omega-conotoxin GVIA, calmidazolium, or (S)-5-isoquinolinesulfonic acid, 4-[2-[(5-isoquinolinyl-sulfonyl)methylamino]-3-oxo-3-(4-phenyl-1-piperaz inyl)-propyl]phenyl ester (KN-62) on CWSS-induced antinociception were studied in ICR mice. The antinociception was assessed by the tail-flick test. CWSS produced inhibition of the tail-flick response. Various doses of nimodipine (10-40 ng), omega-conotoxin GVIA (5-40 ng), calmidazolium (10-40 ng), or KN-62 (5-40 ng) injected i.t. alone did not show any antinociceptive effect in the tail-flick test. I.t. pretreatment with omega-conotoxin GVIA, calmidazolium, or KN-62 dose dependently attenuated the CWSS-induced inhibition of the tail-flick response. However, i.t. pretreatment with nimodipine did not affect the inhibition of the tail-flick response induced by CWSS. Our results suggest that spinal N-type calcium channel, calmodulin and calcium/calmodulin-dependent protein kinase II may be involved in the production of antinociception induced by CWSS. On the other hand, CWSS-induced antinociception appears not to be mediated via the spinal L-type calcium channel. 相似文献
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E. V. Rumyantseva G. A. Vikhoreva N. R. Kil’deeva A. A. Neborako E. Yu. Saraeva L. S. Gal’braikh 《Fibre Chemistry》2006,38(2):98-102
The features of sorption of Cu2+ ions from aqueous solutions of CuSO4 by granulated chitosan sorbent in static conditions and the different contribution of surface and bulk amino groups in the
sorbent to complexation are discussed. Sorption with freshly formed swollen and maximally amorphized granules with accessible
bulk amino groups can be described by Langmuir’s equation; it attains 5.6 mmole/g of dry sorbent, which is close to the sorption
calculated from the equimolar composition of the amino-copper complex. Sorption of initially dry granules with less accessible
bulk amino groups does not obey Langmuir’s equation due to precipitation of copper hydroxide and hydrosulfate on the surface
of the sorbent.
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Translated from Khimicheskie Volokna, No. 2, pp. 11–14, March–April, 2006. 相似文献
6.
Jonathan Wheeler Ángel Galán-Martín Fernando D. Mele Gonzalo Guillén-Gosálbez 《American Institute of Chemical Engineers》2021,67(4):e17131
The design of sustainable supply chains, which recently emerged as an active area of research in process systems engineering, is vital to ensure sustainable development. Despite past and ongoing efforts, the available methods often overlook impacts beyond climate change or incorporate them via standard life cycle assessment metrics that are hard to interpret from an absolute sustainability viewpoint. We here address the design of biomass supply chains considering critical ecological limits of the Earth—planetary boundaries—which should never be surpassed by anthropogenic activities. Our method relies on a mixed-integer linear program that incorporates a planetary boundaries-based damage model to quantify absolute sustainability precisely. We apply this approach to the sugarcane-to-ethanol industry in Argentina, identifying the optimal combination of technologies and network layout that minimize the impact on these ecological boundaries. Our framework can find applications in a wide range of supply chain problems related to chemicals and fuels production, energy systems, and agriculture planning. 相似文献
7.
A new concept for the geometry of a curved beam bistable micromechanical mechanism is proposed aiming at producing a secondary equilibrium state that is more stable (in terms of transformation force) than the primary, stress-free, configuration. The proposed geometry is simple and compatible with common MEMS mass-production processes. A parametric study is performed by means of a non-linear finite-elements analysis in order to study the post-buckling behavior and performance of the mechanism. Based on this analysis, we show that it is theoretically possible to have a mechanism that exhibits a secondary equilibrium state that is more stable than the stress-free configuration. We also find that the post-buckling response of the proposed design is very sensitive to a particular geometrical feature. Besides this particular weakness, the mechanism is rather robust with respect to geometrical inaccuracies. We report our findings with the hope of inspiring others to propose new ideas for overcoming this geometrical sensitivity. 相似文献
8.
Multi-Class Segmentation with Relative Location Prior 总被引:2,自引:0,他引:2
Stephen Gould Jim Rodgers David Cohen Gal Elidan Daphne Koller 《International Journal of Computer Vision》2008,80(3):300-316
Multi-class image segmentation has made significant advances in recent years through the combination of local and global features.
One important type of global feature is that of inter-class spatial relationships. For example, identifying “tree” pixels
indicates that pixels above and to the sides are more likely to be “sky” whereas pixels below are more likely to be “grass.”
Incorporating such global information across the entire image and between all classes is a computational challenge as it is
image-dependent, and hence, cannot be precomputed.
In this work we propose a method for capturing global information from inter-class spatial relationships and encoding it as
a local feature. We employ a two-stage classification process to label all image pixels. First, we generate predictions which
are used to compute a local relative location feature from learned relative location maps. In the second stage, we combine
this with appearance-based features to provide a final segmentation. We compare our results to recent published results on
several multi-class image segmentation databases and show that the incorporation of relative location information allows us
to significantly outperform the current state-of-the-art. 相似文献
9.
Computer systems increasingly carry out tasks in mixed networks, that is in group settings in which they interact both with other computer systems and with people. Participants in these heterogeneous human-computer groups vary in their capabilities, goals, and strategies; they may cooperate, collaborate, or compete. The presence of people in mixed networks raises challenges for the design and the evaluation of decision-making strategies for computer agents. This paper describes several new decision-making models that represent, learn and adapt to various social attributes that influence people's decision-making and presents a novel approach to evaluating such models. It identifies a range of social attributes in an open-network setting that influence people's decision-making and thus affect the performance of computer-agent strategies, and establishes the importance of learning and adaptation to the success of such strategies. The settings vary in the capabilities, goals, and strategies that people bring into their interactions. The studies deploy a configurable system called Colored Trails (CT) that generates a family of games. CT is an abstract, conceptually simple but highly versatile game in which players negotiate and exchange resources to enable them to achieve their individual or group goals. It provides a realistic analogue to multi-agent task domains, while not requiring extensive domain modeling. It is less abstract than payoff matrices, and people exhibit less strategic and more helpful behavior in CT than in the identical payoff matrix decision-making context. By not requiring extensive domain modeling, CT enables agent researchers to focus their attention on strategy design, and it provides an environment in which the influence of social factors can be better isolated and studied. 相似文献
10.
Meir Kalech Sarit Kraus Gal A. Kaminka Claudia V. Goldman 《Autonomous Agents and Multi-Agent Systems》2011,22(1):151-182
Voting is an essential mechanism that allows multiple agents to reach a joint decision. The joint decision, representing a
function over the preferences of all agents, is the winner among all possible (candidate) decisions. To compute the winning
candidate, previous work has typically assumed that voters send their complete set of preferences for computation, and in
fact this has been shown to be required in the worst case. However, in practice, it may be infeasible for all agents to send
a complete set of preferences due to communication limitations and willingness to keep as much information private as possible.
The goal of this paper is to empirically evaluate algorithms to reduce communication on various sets of experiments. Accordingly,
we propose an iterative algorithm that allows the agents to send only part of their preferences, incrementally. Experiments
with simulated and real-world data show that this algorithm results in an average of 35% savings in communications, while
guaranteeing that the actual winning candidate is revealed. A second algorithm applies a greedy heuristic to save up to 90%
of communications. While this heuristic algorithm cannot guarantee that a true winning candidate is found, we show that in
practice, close approximations are obtained. 相似文献