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961.
962.
MIS approach analyzing the controllability of switched boolean networks with higher order 总被引:1,自引:0,他引:1
Lequn Zhang Jun-e Feng Min Meng 《International Journal of Control, Automation and Systems》2014,12(2):450-457
Controllability of higher order switched Boolean control networks (SBCNs) is investigated in this paper. Two algebraic forms of higher order SBCNs are derived. A necessary and sufficient condition of controllability for higher order SBCNs is obtained. An algorithm is derived to calculate the corresponding control and switching-law which drive a point to a given reachable point. Then we talk about the compatibility between our main results and other systems. Finally, two illustrative examples are given to show the validity of the main results. 相似文献
963.
964.
Poly-crystalline In(OH) 3 nanorods have been successfully prepared via a urea-based precipitation using the colloidal carbon spheres as the templates. After calcinations, the resulted In 2 O 3 nanorods with poly-crystalline structure were fabricated. Structure and morphology of the product were characterized by X-ray diffraction (XRD), and transmission electron microscopy (TEM). The possible formation process was schemed. The sensor gas properties towards C 2 H 5 OH and CO were examined. 相似文献
965.
以上海二手房房价指数为实证样本,应用R/S分析法研究上海房价波动的长记忆特性,计算得到Hurst指数及关联尺度函数并进而确定了V统计量曲线的转折点。结果表明,上海二手房房价指数每隔2.5年即出现明显转折,证明了上海二手房房价指数存在显著的长记忆特性,未来房价受到现在房价很大的影响,上海二手房房价的可预测性很强,对于帮助工程投资风险的预测有实际的意义。 相似文献
966.
消防服是消防人员灭火作业时的防护服装。在服用过程中,其性能会受环境因素(强热流、热辐射、日晒、水分等)的影响,功能不断衰退。回顾了国内外对单一环境因素和复合环境因素的研究,阐述了研究现状和研究空白,并预测了这一研究的发展趋势。 相似文献
967.
968.
The synthesis of a new cholesteric monomer ( MLC) containing menthyl groups and a series of cholesteric elastomers ( LCE1−LCE4 ) is described. Their chemical structures and purity were characterized by FTIR, 1H-NMR, and elemental analyses. The phase behavior and thermal stability were investigated by differential scanning calorimetry, polarizing optical microscopy, X-ray diffraction, and thermogravimetric analysis. By inserting a flexible spacer between the mesogenic core and the terminal menthyl groups, mesomorphism of M LC was realized. LCE1−LCE4 with low content of crosslinking unit exhibited cholesteric phase because of the introduction of the nematic crosslinking unit. This indicates that low levels of chemical crosslinking do not significantly affect the phase behavior and mesomorphism of the elastomers, and reversible mesophase transitions can be observed. In addition, with increasing the content of crosslinking unit, the corresponding Tg decreased for LCE1−LCE4 , whereas their Ti did not remarkable change. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
969.
污水厌氧处理系统中溶解性微生物产物的研究进展 总被引:1,自引:0,他引:1
污水厌氧处理系统中产生的溶解性微生物产物(SMP)因其自身的性质、潜在危害性等逐渐引起国内外学者的重视。综述了国内外对厌氧SMP的研究成果,系统阐述了厌氧SMP的性质及影响其产生的运行参数。对其生成与降解数学模型的发展进行了综述。最后对今后厌氧SMP的研究方向作出了展望。 相似文献
970.
Liang HuJie Qin Nan ZhouYi-Fei Meng Yan XuJing-Lin Zuo Xiao-Zeng You 《Dyes and Pigments》2012,92(3):1223-1230
Metal complexes containing a new multi-sulfur atom containing 1,2-dithiolene ligand, [4′,5′:5,6] [1,4] dithiino[2,3-b] quinoxaline-1′,3′-dithiolate, have been synthesized and characterized by electrochemical measurements, IR, UV-NIR and ESR spectroscopies. X-ray structure analysis reveals that the anions of the Ni-complex derived from the new ligand form a zig-zag chain along the b axis, and the anions of Au complex of the ligand stack along the a axis while the cations occupy the holes. The Ni-complex exhibits remarkable absorption at 1082 nm (? = 15?000 dm3 mol−1 cm−1) and good solubility that render this complex as a promising near-IR dye for Q-switching neodymium lasers. The third-order non-linear optical properties of the complexes are measured by the Z-scan technique with a 6.5 ns pulsed laser at 532 nm. The Au complexes exhibit non-linear optical absorptive abilities, while the non-linear absorption of the nickel complex is negligible. All of the complexes show effective self-defocusing performance. The third-order non-linear optical susceptibilities for the Au complexes have been determined to be of the order of 10−13 esu. 相似文献