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991.
The changes of parameters and topology in a complex network often lead to unexpected accidents in complex systems, such as diseases in neural systems and unexpected current in circuit system, so the methods of adjusting the abnormal network back to its normal conditions are necessary to avoid these problems. However, it is not easy to detect the structures and information of each network, even if we can find a network which has the same function as the abnormal network, it is still hard to use it as a reference to adjust the abnormal network because a lot of network information is unknown. In this paper, we design a "bridging network" as an information bridge between a normal network and an abnormal network to estimate and control the abnormal network. Through the "bridging network" and some adaptive laws, the abnormal parameters and connections in abnormal network can be adjusted to the same conditions as those of the normal network which is chosen as a reference model. Finally, the "bridging network" and the abnormal network achieve synchronization with the normal network. Besides, the detailed inner information in normal network and abnormal network can be accurately estimated by this "bridging network." Finally, the nodes in the abnormal network will behave normally after the correction. In this paper, we use Hindmarsh-Rose model as an example to describe our method. 相似文献
992.
We report a continuous-wave (CW) green laser emission by sum-frequency mixing in Nd:GdVO4 and Nd:YLF crystals. Using type-I critical phase-matching (CPM) LBO crystal, a green laser at 538 nm is obtained by 912 and
1313 nm intracavity sum-frequency mixing. The maximum output power of 185 mW is obtained when an incident pump laser of 18.2
W is used. At the output power level of 185 mW, the output stability is better than 3.3%. 相似文献
993.
Konstantin Tarasov Patricia Beaunier Michel Che Eric Marceau Yanling Li 《Journal of nanoparticle research》2011,13(5):1873-1887
Following procedures formerly developed for the preparation of supported heterogeneous catalysts, carbon-coated cobalt nanoparticles
dispersed on porous alumina have been prepared by impregnation of γ-Al2O3 with (NH4)2[Co(EDTA)] and thermal decomposition in inert atmosphere. Below 350 °C, Co(II) ions are complexed in a hexa-coordinated way
by the EDTA ligand. The thermal treatment at 400–900 °C leads to the EDTA ligand decomposition and recovering of the support
porosity, initially clogged by the impregnated salt. According to X-ray absorption spectroscopy, and due to in situ redox
reactions between the organic ligand and Co(II), both oxidic and metallic cobalt phases are formed. Characterisation by transmission
electron microscopy, X-ray diffraction and magnetic measurements reveals that an increase in the treatment temperature leads
to an increase of the degree of cobalt reduction as well as to a growth of the cobalt metal particles. As a consequence, the
samples prepared at 400–700 °C exhibit superparamagnetism and a saturation magnetisation of 1.7–6.5 emu g−1 at room temperature, whilst the sample prepared at 900 °C has a weak coercivity (0.1 kOe) and a saturation magnetisation
of 12 emu g−1. Metal particles are homogeneously dispersed on the support and appear to be protected by carbon; its elimination by a heating
in H2 at 400 °C is demonstrated to cause sintering of the metal particles. The route investigated here can be of interest for obtaining
porous magnetic adsorbents or carriers with high magnetic moments and low coercivities, in which the magnetic nanoparticles
are protected from chemical aggression and sintering by their coating. 相似文献
994.
Liu L Bruhn T Guo L Götz DC Brun R Stich A Che Y Bringmann G 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(9):2604-2613
Chloropupukeanolides C–E ( 8 – 10 ), three highly functionalized secondary metabolites featuring a novel spiroketal skeleton derived from the chlorinated tricyclo‐[4.3.1.03, 7]‐decane (pupukeanane) and the 2,6‐dihydroxy‐4‐methylbenzoic acid moieties, were isolated from the scale‐up fermentation extract of the plant endophytic fungus Pestalotiopsis fici. The constitutions of compounds 8 – 10 were elucidated primarily by NMR experiments. Their relative configurations were deduced by analogy to metabolites 4 – 6 , which were previously isolated from the same fungus. The absolute configuration of 8 was assigned by X‐ray crystallography and those of 9 and 10 by quantum‐chemical CD calculations. Biogenetically, chloropupukeanolides C–E ( 8 – 10 ) are presumably derived from the same oxidation‐induced Diels–Alder reaction pathway as compounds 1 and 4 – 7 , via the putative biosynthetic precursors 2 and 3 . The opposite configurations of the complete “Southern parts” of 8 and 9 suggests that this Diels–Alder reaction is stereochemically not very selective. Compounds 8 – 10 showed significant cytotoxicity against a small panel of human tumor cell lines and weak activities against the pathogens of tropical diseases. 相似文献
995.
996.
Shaohui Hong Defu Zhang Hoong Chuin Lau XiangXiang Zeng Yain-Whar Si 《European Journal of Operational Research》2014
In this paper, we consider the two-dimensional variable-sized bin packing problem (2DVSBPP) with guillotine constraint. 2DVSBPP is a well-known NP-hard optimization problem which has several real applications. A mixed bin packing algorithm (MixPacking) which combines a heuristic packing algorithm with the Best Fit algorithm is proposed to solve the single bin problem, and then a backtracking algorithm which embeds MixPacking is developed to solve the 2DVSBPP. A hybrid heuristic algorithm based on iterative simulated annealing and binary search (named HHA) is then developed to further improve the results of our Backtracking algorithm. Computational experiments on the benchmark instances for 2DVSBPP show that HHA has achieved good results and outperforms existing algorithms. 相似文献
997.
998.
Zhiping Liu Jie Pang Lijie Che Liping Pang Chunfang Gan Jianguo Cui Yanmin Huang 《Journal of heterocyclic chemistry》2024,61(3):474-482
A Sc(OTf)3-catalyzed tandem (3 + 3)-annulation/lactonization of donor-acceptor cyclopropane 1,1-dieters with salicylaldehyde nitrones has been reported, affording a wide range of tetrahydrochromeno[4,3-c][1,2]oxazin-5(1H)-ones in moderate yields with excellent diastereoselectivities. Besides, the gram-scale reaction has also been explored to demonstrate the utility of this protocol. Moreover, the mechanism was investigated through control experiments, which show the reaction proceeds via a tandem (3 + 3)-annulation/lactonization reaction. 相似文献
999.
1000.
激光散斑在MTF测试中的应用 总被引:1,自引:0,他引:1
论述激光散斑的产生方法及其数据处理,并给出数据处理部分的简单流程图。 相似文献