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61.
62.
Jili Wang Linshan Wang 《Annals of Differential Equations》2014,(2):184-190
In this paper, the stability in Lagrange sense of a class of stochastic static neural networks with mixed time delays is studied. Based on the Lyapunov stability theory and with the help of stochastic analysis technique, the criteria for the stability in Lagrange sense of stochastic static neural networks with mixed time delays is obtained. One example is given to verify the advantage and applicability of the proposed results. 相似文献
63.
研究了一类具有比率和单调功能反应的中立型捕食系统.通过利用重合度理论获得了其正周期解存在性的充分条件,推广和改进了已有文献的相关结果. 相似文献
64.
静冰压力是指冰层在升温膨胀受到约束的条件下,对约束体产生的压力.它是高寒地区水工建筑物的一种特殊载荷,也是冰科学和冰工程研究中最关键的物理指标之一.主要介绍了几种测量与确定静冰压力的方法及其存在的问题,并着重研究了适合测量静冰压力的光纤光栅传感器的工作原理和结构设计,提出了静冰压力在线检测系统的设计方法,解决了光纤光栅压力传感器的温度补偿问题.通过初步的研究表明,基于光纤光栅的静冰压力传感器具有尺寸小、分布式绝对测量、抗腐蚀能力强、抗干扰、适合于定点连续自动监测等优点. 相似文献
65.
利用不同煤种的煤和生物油制备了不同浓度的生物油煤浆,考察了生物油煤浆的成浆浓度、表观黏度、流变特性和稳定性。结果表明,生物油煤浆是具有一定屈服应力的非牛顿流体,其流变特性可用宾汉姆方程来描述;生物油煤浆的屈服应力和表观黏度都随着固体浓度的增加而增大;随着剪切速率的增加,生物油煤浆的表观黏度减小;四种煤中,无烟煤的成浆浓度最高,可达42%,其含碳量高达49%,相当于同种煤制成的74%的水煤浆含量。烟煤次之,褐煤最低;生物油与煤粉之间能够形成絮凝性的大分子网络结构,使得生物油煤浆存在屈服应力并能够保持良好的静态稳定性,4.0~5.0 d天没有软沉淀产生,数月没有硬沉淀产生。 相似文献
66.
V. Chandra Z. Huang W. Qiu R. Kumar 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(3):255-280
Interaction of multiple discrete event systems (DESs) represented as automata are carried out using composition operations. These operations on automata enforce concurrency, wherein an event exists in the composed automaton if it exists in the participating states of the interacting automata possessing the event in their event set. Heymann generalized this by introducing event priorities, wherein an event exists in the composed automaton if it exists in the participating state of the interacting automata having priority over the event. For two interacting automata P and Q, while prioritized composition can model the P, Q, AND, and OR boolean interactions, it cannot model boolean interactions which require exclusivity of participation, namely, “exclusive P”, “exclusive Q”, “exclusive P or exclusive Q”, “exclusive P and exclusive Q”. In order to also model these additional interactions we propose a generalization of prioritized composition by introducing an exclusivity set besides the existing priority sets. The resulting composition is called prioritized composition with exclusion. We also introduce prioritized composition with exclusion and generation that allows for all sixteen boolean modes of interaction possible when two automata interact. This is done by the further introduction of a nor-generative set. This event set together with the two priority sets and an exclusivity set makes it possible to model eight additional boolean interactions which do not require either of the interacting automata to participate for the event to be enabled in the composed automaton. The applicability of these interactions to decentralized supervisory decision fusion and in composing the rules based model of systems has been illustrated. 相似文献
67.
A nearly half-filled two-dimensional Heisenberg model is investigated. A slave-fermion method with fermions as the charge carriers and bosons as the spin carriers is proposed. The ground state shows antiferromagnetic long range order at T = 0. The spin-spin correlation and static susceptibility are also obtained. 相似文献
68.
冯志刚 《中国惯性技术学报》2007,(8)
全球定位系统为公路勘测设计工作者提供了一个可靠的提高外业测量精度及进度的工具,随着GPS越来越多地出现在人们的生产、生活中,这一先进的测量手段会被更广泛地应用到公路勘测工作中,从而可提高作业效率,缩短设计周期,推动交通事业的发展和公路的建设。 相似文献
69.
The performance of three-colour HgCdTe photovoltaic heterostructure detector is examined theoretically. In comparison with
two-colour detectors with two back-to-back junctions, three-colour structure contains an absorber of intermediate wavelength
placed between two junctions and electronic barriers are used to isolate this intermediate region. This structure was first
proposed by British workers.
Three-detector structures with different localizations of separating barriers are analyzed. The calculation results are presented
in the form of spatial distributions of bandgap energy and quantum efficiency.
Enhanced original computer programs are applied to solve the system of non-linear continuity equations for carriers and Poisson
equations. In addition, the numerical analysis includes the dependence of absorption coefficient on Burstein effect as well
as interference effects in heterostructure with metallic electrical contacts.
It is shown that the performance of the detector is critically dependent on the barrier’s doping level and position in relation
to the junction. This behaviour is serious disadvantage of the considered three-colour detector. A small shift of the barrier
location and doping level causes serious changes in spectral responsivity. 相似文献