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排序方式: 共有192条查询结果,搜索用时 15 毫秒
31.
A general multiscroll Lorenz system family and its realization via digital signal processors 总被引:1,自引:0,他引:1
This paper proposes a general multiscroll Lorenz system family by introducing a novel parameterized nth-order polynomial transformation. Some basic dynamical behaviors of this general multiscroll Lorenz system family are then investigated, including bifurcations, maximum Lyapunov exponents, and parameters regions. Furthermore, the general multiscroll Lorenz attractors are physically verified by using digital signal processors. 相似文献
32.
软件Agent遇到语义二义性时无法正确地为用户解决矛盾问题.利用本体支持语义互操作的特点,在软件Agent策略生成机制中引入复合元本体,加入Agent智能引导的人机交互方法,实现了具有语义歧义消除能力的可拓策略生成系统.当用户输入的问题信息语义模糊时,Agent根据本体中的知识与用户交互,逐步理解用户的信息语义,直到能为用户生成解决矛盾问题的策略.以旅游与购物问题为例进行了实验,结果表明了软件Agent策略生成的语义互操作能力得到了提高. 相似文献
33.
2,4-Bis(3,5-dimethylpyrazol-1-yl)-6-methoxyl-1,3,5-triazine(bpt) has been synthesized by using a new, simple and general method
with high yields. Reactions of bpt with Ni(ClO4)2·6H2O and Zn(ClO4)2·6H2O in methanol gave mononuclear complex [Ni(bpt)2]· (ClO4)2·H2O and ternary complex [Zn(mpt)2(dmp)](ClO4)2 respectively, where mpt (2,4-dimethoxy-6-(3,5-dimethyl- pyrazol-1-yl)-1,3,5-triazine) and dmp(3,5-dimethylpyrazole) are the
alcoholysis products of bpt in the presence of Zn2+ ion. A possible mechanism for this catalytic reaction was proposed. X-ray crystal structure for ligand bpt, Ni and Zn complexes
are reported. The protonated form of the ligand bpt crystallizes as its perchlorate salt including one molecule of water,
[Hbpt·H2O·ClO4]. The proton is located on one pyrazole N-atom. [Hbpt·H2O·ClO4], in which [Hbpt]+ is in cis-cis conformation, are packed in slipped stacks of approximately parallel layers. The Π -Π overlap interactions
between the non-protonized pyrazoles of the adjacent layers give a zigzag arrangement of the planar aromatic [Hbpt]+ molecules. In [Ni(bpt)2](ClO4)2·H2O, bpt are meridionally three-coordinated with Ni2+. The coordination sphere around Ni2+ is a slightly distorted square bipyramid, where four pyrazole nitrogen atoms occupy the basal positions and two triazine
nitrogen atoms the apical one. In [Zn(mpt)2(dmp)](ClO4)2, the Zn atom is coordinated with a pair of bidentate mpt ligands and one monodentate dmp ligand, forming a distorted trigonal
bipyramid, where the two triazine nitrogen atoms of mpt and one nitrogen atom of dmp occupy the basal positions, and the two
pyrazole nitrogen atoms of mpt the apical one. 相似文献
34.
Chunhua ZHANG Fugen WU Chunyan WU Fa OU Department of Physics Guangdong University of Technology Guangzhou China Department of Applied Physics South China University of Technology Guangzhou China 《Communications in Nonlinear Science & Numerical Simulation》2000,5(1):36-43
IntroductionThe multistability in chemical reaction has been paid much attention to at all timesll--3].As chemical multistability acts at the non-linear area, and its critical phenomenon is part ofnon-equilibrium statistical mechanics of non-linearity, we usually take the critical phenomenaand phase transition in the equilibrium thermodynamic for -reference when we discuss the critical phenomena and phase transition in non-linear systemsl'--6]. As we all know, Ehrenfest (see,for example, [7]) … 相似文献
35.
阵列相关系数比对法在中药鉴别中的应用研究 总被引:2,自引:0,他引:2
中药材红外光谱具有“指纹”性,通过对红外特征吸收谱图的比对可达到区分和鉴别药材的目的。该研究用Visual Basic 6.0设计了中药材红外光谱阵列相关系数比对软件,建立了300多种中药药材的红外光谱数据库,将未知药材的红外光谱与数据库中药材的红外光谱进行比对,它能依11个波段两光谱相关系数的大小自动找到与库中最相似的光谱的药材,从而达到鉴别未知药材的目的。研究结果表明:在光谱数据库所包含的药材范围内,指定阵列相关系数的阈值,抓住特征波段光谱的比对,可避开CO2和H2O等外界因素对谱图的干扰,使比对结果准确可靠。该法有望成为中药材快速鉴别的一种常规手段。 相似文献
36.
1 IntroductionThe problem of periodic solutions of nonlineax dtherential equations has been one Of thecenter problem to the tI1eory of differelltial equatiol1, it 11as wide application baCkground(8uchas fOrce oscillatioll of telecomnmnication, periodic euvironment in econondc system, etc.), soit has been a popular subject in the research work. In this paperl we discuss the problem ofperiodic solutions of the fOllowing nolllinear lleutral functional differential equatiollsd,dtD(ft xt) = f(f, … 相似文献
37.
A three-fernion system with their spin aligned is examined to reveal that the quantum mechanical symmetry plays a decisive role in determining microscopic structures. 相似文献
38.
该文研究一个反应扩散方程组的自由边界问题,它来源于描述抑制物作用下无坏死核肿瘤生长的数学模型.作者运用抛物型方程的Lp理论和压缩映照原理,证明了这个问题局部解的存在唯一性,然后用延拓方法得到了整体解的存在唯一性. 相似文献
39.
《Physics letters. A》2005,339(6):478-487
In this Letter, the localized defect modes of water waves over two-dimensional periodic bottoms with a point defect are investigated by supercell calculations and plane-wave expansion method. Two kinds of defects are introduced, one is a radius defect created by changing radius of cylinder, and another is a depth defect created by changing its depth. The results indicate that both can create defect modes, and the amplitude distributions of the defect modes are well localized in the vicinity of the defects with various patterns. The influences of radius and depth of defect cylinder on the defect modes are investigated in detail. 相似文献
40.
利用生成函数解决了从n个元素的集合中任意重复选取r个元素且这r个元素中含有不同元素的个数一定时,所构成的不同r-序列的方法数. 相似文献