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1.
A microscopic cluster model with a fully correlated Gaussian basis is developed. In the model, the stochastic variational method is used in order to calculate the ground-energy and the mean-square radius conveniently. Based on this model, the ground-energy level and radius of the neutron halo nucleus, 6He, are calculated as a α+n+n three-cluster model. The results are in good agreement with the experimental data.  相似文献   
2.
We present a novel cluster-seven-core photonic crystal fiber which possesses high nonlinearity and supports the high-power pumping. Its nonlinearity coefficient and effective mode area are calculated by the full vector multipole method. Compared with the single core PCF, the cluster-seven-core photonic crystal fiber can support high-power beam transmitting in the core, and simultaneously has high nonlinearity. This kind of photonic crystal fiber can be applied to the photoelectron-device field.  相似文献   
3.
群集的研究是理解生物复杂性,研究智能人工多自主系统的重要方面。基于经典VICSEK模型,提出异质的自适应速度模型,并研究其涌现行为,从而帮助建立能有效提高离散群集系统的涌现行为发生即收敛概率的机制。  相似文献   
4.
集值映射向量优化问题的ε—超有效解   总被引:5,自引:1,他引:4  
凌晨 《运筹学学报》2001,5(3):51-56
本文引进了集值映射向量优化问题的ε-超有效解概念,并在集值映射为近似广义锥次似凸的假设下,建立了关于ε-超有效解的标量化定理和Lagrange乘子定理。  相似文献   
5.
We introduce a two-species symbiosis-driven growth model, in which two species can mutually benefit for their monomer birth and the self-death of each species simultaneously occurs. By means of the generalized rate equation, we investigate the dynamic evolution of the system under the monodisperse initial condition. It is found that the kinetic behaviour of the system depends crucially on the details of the rate kernels as well as the initial concentration distributions. The cluster size distribution of either species cannot be scaled in most cases; while in some special cases, they both consistently take the universal scaling form. Moreover, in some cases the system may undergo a gelation transition and the pre-gelation behaviour of the cluster size distributions satisfies the scaling form in the vicinity of the gelation point. On the other hand, the two species always live and die together.  相似文献   
6.
<正> 本文将讨论非结合环的推广—群集的F-根。在非结合环中,两个元素的和不依赖加法的顺序。如果除去这条限制,便得到一个新的代数系统,我们称它为群集。(Cluster)  相似文献   
7.
提出了一种测定奶品中群集成分的非线性化学方法,并将其用于为测定掺杂在羊奶中的牛奶和马奶的含量.首先,在不同温度下测定不同掺杂比的混合奶标样与纯羊奶的非线性化学指纹图谱诱导时间之差,利用该差值与混合奶中各原奶含量的多元线性关系,通过最小二乘法建立测定混合奶中各原奶含量的系统模型;然后,用此模型及相同条件下测得的混合奶试样与纯羊奶指纹图谱的诱导时间之差,计算出该试样中各原奶含量,并据此来鉴别奶品种类及掺杂程度.结果表明,测定值与真实值之间相关系数为0.9991,RSD为0.77%~4.3%,回收率为93.2%~105.5%,掺杂牛奶和马奶含量的检出限分别为1.93%和2.81%;该方法重现性好、准确度高,可同时测定多元混合奶中各原奶的含量,也能准确鉴别出奶品种类;其原理具有通用性,可供其它复杂样品定量分析借鉴和应用.  相似文献   
8.
The evolutionary prisoner's dilemma game is investigated under different initial distributions for cooperators and defectors on scale-free networks with a tunable clustering coefficient. It is found that, on the one hand, cooperation can be enhanced with the increasing clustering coefficient when only the most connected nodes are occupied by cooperators initially. On the other hand, if cooperators just occupy the lowest-degree nodes at the beginning, then the higher the value of the clustering coefficient, the more unfavorable the environment for cooperators to survive for the increment of temptation to defect. Thereafter, we analytically argue these nontrivial phenomena by calculating the cooperation probability of the nodes with different degrees in the steady state, and obtain the critical values of initial frequency of cooperators below which cooperators would vanish finally for the two initial distributions.  相似文献   
9.
We introduce a modification of reflectron time-of-flight mass spectrometer for laser photodissociation of mass-selected ions. In our apparatus, the ions of interests were selected by a mass gate near the first space focus point and decelerated right after the mass gate, were then crossed by a laser beam for dissociation. The daughter ions and surviving parent ions were re-accelerated and analyzed by the reflectron time-of-flight mass spectrometer. Compared to the designs reported by other research groups, our selection-deceleration-dissociation-reacceleration approach has better daughter-parent-ions-separation, easier laser timing, and better overlapping between the ion beam and laser beam. We also conducted detailed cal- culations on the parent ion and daughter ion flight times, and provided a simplified formula for the calibration of daughter ion mass.  相似文献   
10.
针对多无人机群三维空间运动的复杂群集控制问题,提出了基于生物群集行为、依据Reynolds规则描述的三维群集控制算法。已有的研究大多将无人机群集运动简化为二维平面运动,但这不符合实际控制需求。为此,将群集控制算法和人工势场算法推广到三维无人机群集控制中,建立了三维无人机群空间运动模型,通过多种不同条件下的仿真,研究了两种算法在三维群集控制中的有效性。结果显示两种算法用于三维群集控制均具有一定效果,但相对二维所需要的条件更为苛刻。同时,注意到智能算法具有更好的群体聚集效果,而人工势场算法则避碰效果更迅速明显。据此,对人工势场算法和智能算法进行了改进,通过在距离大于平衡点时采用智能算法聚集,在距离小于平衡点时采用人工势场算法避碰,得到能同时获得更好的聚集、避碰效果的新的群集控制算法。  相似文献   
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