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961.
In this paper, inspired by the idea that different nodes should play different roles in network synchronization, we bring forward a coupling method where the coupling strength of each node depends on its neighbors' degrees. Compared with the uniform coupled method and the recently proposed Motter-Zhou-Kurths method, the synchronizability of scale-free networks can be remarkably enhanced by using the present coupling method, and the highest network synchronizability is achieved at β=1 which is similar to a method introduced in [AIP Conf. Proc. 776, 201 (2005)].  相似文献   
962.
IfH andG are the transfer function matrix and the free response matrix of a linear finite automaton, thenG is called a free response matrix matched toH. GivenH, letG(H) be the set of all possible free response matrices matched toH. A classification and an enumeration on the setG(H) are given in this paper. Supported by National Natural Science Foundation  相似文献   
963.
Vapor-liquid equilibrium (VLE) data for the system ethyl acetate + ethanol in the presence of 1,2-propanediol at concentrations of 0%, 20%, 30%, and 40% by weight were measured at 101.3 kPa. The experimental VLE data of the ternary system ethyl acetate + ethanol + 1,2-propanediol were correlated by the Margules, Wilson, NRTL, and UNIQUAC liquid models. The relative volativities of ethyl acetate with respect to ethanol were also determined. The results of the investigation indicate the disappearance of the binary azeotrope between ethyl acetate and ethanol at the solvent concentrations studied in this work.  相似文献   
964.
本文给出了一类随机不可微规划的实施方案。数字实验表明,这种实施方案是可行的。  相似文献   
965.
给出了线性方程组Ax=b的反问题在n阶矩阵类中解的一般形式.  相似文献   
966.
针对反作用控制系统(Reaction Control System,RCS)快速响应电磁阀频繁工作的特性,从节能控制的角度出发,设计了一种基于脉宽调制(Pulse Width Modulation,PWM)技术的电磁阀控制驱动方案。建立电磁阀电路模型,通过仿真计算,确定了PWM频率及占空比对电磁阀线圈电流的影响,为电磁阀驱动电路参数的选取提供依据。搭建RCS电磁阀电流测试平台,设定PWM占空比为50%,试验结果表明:流经电磁阀的保持电流仅为开启电流的1/2,既能保证电磁阀正常开启,又避免了电磁阀处于高负载工作状态,有效地验证了该节能控制方案的正确性。  相似文献   
967.
 A promising electrochemical sensor was fabricated by electrodeposition of Pd nanoparticles (PdNPs) on poly(thiophene-3-acetic acid) (PTAA)-modified glassy carbon electrode (GCE), forming a PdNPs/PTAA composites-modified GCE (PdNPs/PTAA/GCE). Scanning electron microscope (SEM) and electrochemical techniques were used for the characterization of these composites. It was found that the PdNPs/PTAA layer was very uniform. Electrochemical experiments showed that this proposed PdNPs/PTAA composites-modified electrode exhibited excellent electrocatalytic activity towards the oxidation of hydrazine. Under the optimum conditions, the proposed sensor can be applied to the quantification of hydrazine with a wide linear range from 8.0?10-9 mol/L to 1.0?10-5 mol/L with a low detection limit of 2.67?10-9 mol/L. The experiment results also showed that the sensor exhibited good reproducibility and long-term stability, as well as high selectivity with no interference from other potential competing species.  相似文献   
968.
Thermal instabilities of de-lithiated materials with organic carbonates were verified by DSC. Transition metal oxides FePO4, NiO2, Mn2O4, and Co3O4 were mixed with DEC, DMC, EC, EMC, and PC then dynamically screened to about 500 °C. Curves were acquired and analyzed to determine exothermic onset temperatures and reaction enthalpies. These data for assessing the thermal hazards of conditions were compared to those data published in literature.  相似文献   
969.
This paper presents a modified ODE-based algorithm for unconstrained optimization problems. It combines the idea of IMPBOT algorithm with nonmonotone and subspace techniques. The main feature of this method is that at each iteration, a lower dimensional system of linear equations is solved to obtain a trial step. Under some standard assumptions, the method is proven to be globally convergent. Numerical results show the efficiency of this proposed method in practical computation.  相似文献   
970.
通过应用广义次微分来研究不可微规划的最优解,得到了适当函数类在强意义下的最优性条件,并给出了广义次微分在稳定性理论和极小化方法中的应用  相似文献   
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