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11.
Xiang-dong Hou 《Journal of Combinatorial Theory, Series A》2007,114(3):522-544
Let Ψn be the number of inequivalent self-dual codes in . We prove that , where . Let Δn be the number of inequivalent doubly even self-dual codes in . We also prove that . 相似文献
14.
Matthew Elder 《Discrete Mathematics》2008,308(16):3479-3490
A path bundle is a set of 2a paths in an n-cube, denoted Qn, such that every path has the same length, the paths partition the vertices of Qn, the endpoints of the paths induce two subcubes of Qn, and the endpoints of each path are complements. This paper shows that a path bundle exists if and only if n>0 is odd and 0?a?n-⌈log2(n+1)⌉. 相似文献
15.
在中高能质子诱发散裂反应相关核工程设计中,可靠的蒙特卡罗模拟程序结合核反应理论模型具有较好的理论指导意义。本工作中,利用GEANT4耦合INCL4和ABLA理论模型以及FLUKA耦合PEANUT模型模拟计算了几百MeV至几个GeV质子轰击Be,Al,Fe,W,U等靶后30°,60°,120°,150°出射角产生的散裂中子双微分截面,并与现有实验数据进行了比较。结果发现,FLUKA和GEANT4模拟计算较好地再现了Al,Fe,W,U等靶实验测量数据。然而,模拟结果明显低估了Be靶出射中子能量小于10 MeV能区的实验数据。For the design of nuclear engineering related with medium-high energy proton induced spallation reaction,the reliable Monte Carlo simulation codes coupled with nuclear reaction models have a good theoretical guidance.In this work,the production spallation neutron double differential cross sections at 30°,60°,120°,150°emission angle for Be,Al,Fe,W,U target materials at incident proton energies between several hundred MeV and GeV are theoretically calculated by using the GEANT4 coupled INCL4 and ABLA,and the FLUKA coupled PEANUT.The calculated results were compared with the available experimental data.It is found that the GEANT4 and FLUKA calculations well reproduced the experimental measurement of Al,Fe,W,U target materials.However,calculations obviously underestimated the emission neutrons of Be target for lower than 10 MeV energy range. 相似文献
16.
汉明码编译码的FPGA设计与实现 总被引:2,自引:0,他引:2
利用ALTERA公司的FLEX10K系列芯片设计和实现了汉明码的编译码,详细地阐述了设计的方法和实现的过程。首先进行电路设计,然后在MAX PLUSII编辑环境下,采用自顶向下的层次设计方法,以及VHDL文本输入的输入方法编制程序,经编译正确后进行波形仿真,经过仿真、调试,验证了功能和时序正确性后,将编辑的程序烧写到FPGA。 相似文献
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18.
An ultrasensitive aptamer-based bio bar code immunomagnetic separation and electrochemiluminescence (IM-ECL) method for the detection of protein is developed. The target protein is captured by biotin-labeled aptamer (biotin probe) and [Ru(bpy)3]2+ (TBR)-Au bio bar code-labeled aptamer (ECL nanoprobe), to form a double aptamer–protein sandwich complex. The complex is then immobilized on the streptavidin microbeads through biotin–streptavidin linkage and detected by ECL assay. The ECL signal of the target protein is amplified by the TBR-bio bar code DNAs. As an example, platelet-derived growth factor B-chain homodimer (PDGF-BB) was detected by the method. Experimental results show that the detection limit of the assay is 1 pM of PDGF-BB. A calibration curve with a linearity range from 1 pM to 10 nM is established, thus, make quantitative analysis possible. The method has been used to detect PDGF-BB in fetal calf serum with minimum background interference. Due to the wide availability of aptamer for numerous proteins, this aptamer-based bio bar code IM-ECL method holds great promise in protein detection. 相似文献
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20.
Kholmirzo Kholmurodov William Smith Kenji Yasuoka Tom Darden Toshikazu Ebisuzaki 《Journal of computational chemistry》2000,21(13):1187-1191
An N⋅ log (N) smooth‐particle mesh Ewald method has been incorporated into the DL_POLY molecular dynamics simulation package. The performance of the new code has been tested on a Fujitsu VPP700 for several DL_POLY‐specific benchmark systems. The new method is highly vectorizable, and makes use of the extremely efficient Fast Fourier Transforms on the Fujitsu vector machine. In calculations of the coulombic forces in periodic systems requiring large reciprocal space vectors, the new code was found to be considerably faster than the conventional Ewald method. © 2000 John Wiley & Sons, Inc. J Comput Chem 21: 1187–1191, 2000 相似文献