随机相互作用的原子核等多体系统的性质

讨论了随机相互作用下原子核等多体系统的基态和低激发态性质研究方面的进展情况。

随机相互作用下原子核的非集体转动行为研究

随机相互作用下原子核基带能级呈现的非集体转动行为是鲁棒性的现象,即基带能级的数学期望值与角动量的平方呈正相关关系。本文在sd壳和pf壳模型空间下计算了包括^(24)Mg、^(28)Si、^(46)Ca、^(46)Ti的偶偶核以及包括^(21)Ne、^(43)Sc的奇质量数原子核在随机相互作用下基带的能级结构,验证了非集体转动行为在基态非零自旋以及奇质量数原子核下的鲁棒性,同时指出了数学期望值与角动量的平方的线性相关性非常好,而对于最小角动量能级大于最大角动量能级的样本,“逆”非集体转动行为也较为普遍。同时比较和讨论了偶偶核基态是否为零自旋对激发态的能级结构的影响,结果表明,当偶偶核基态自旋不为零时,基带低激发态能级顺序呈现出更多随机性。

随机相互作用下基态零自旋几率的两体矩阵元相关性

原子核在随机相互作用下呈现出偶偶核基态零自旋占优的现象。过去的研究表明这一现象与两体矩阵元相关。在此基础上,通过改变随机两体系综的每一个两体矩阵元的分布宽度,增强该两体矩阵元的影响,同时保留其他两体矩阵元的分布,分析偶偶核在此系综下的基态零自旋几率。本文发现了基态零自旋几率对某些两体矩阵元不敏感。在此基础上以真实剩余两体相互作用作为随机两体矩阵元分布的中心值,发现了基态零自旋几率与两体矩阵元分布的中心值相关度很大。

随机相互作用系综内的镉同位素电磁矩线性演化

在随机相互作用系综内,镉同位素11/2-同质异能态的电四极矩与磁偶极矩总是倾向于随中子数的增加呈线性演化,这与近年来的实验观测是一致的。除了对力对磁矩线性演化的决定性影响之外,特定形式的质子-中子相互作用被认为是这种线性演化的主要驱动力:电矩的线性演化要求质子中子之间的四极相互作用;磁矩则要求质子中子之间的短程相互作用,并且这种相互作用应具有与真实核相互作用一致的相对强度与正负性。

A novel refined dynamic model of high-speed maglev train-bridge coupled system for random vibration and running safety assessment

Running safety assessment and tracking irregularity parametric sensitivity analysis of high-speed maglev train-bridge system are of great concern,especially need perfect refinement models in which all properties can be well characterized based on various stochastic excitations.A three-dimensional refined spatial random vibration analysis model of high-speed maglev train-bridge coupled system is established in this paper,in which multi-source uncertainty excitation can be considered simultaneously,and the probability density evolution method(PDEM)is adopted to reveal the system-specific uncertainty dynamic characteristic.The motion equation of the maglev vehicle model is composed of multi-rigid bodies with a total 210-degrees of freedom for each vehicle,and a refined electromagnetic force-air gap model is used to account for the interaction and coupling effect between the moving train and track beam bridges,which are directly established by using finite element method.The model is proven to be applicable by comparing with Monte Carlo simulation.By applying the proposed stochastic framework to the high maglev line,the random dynamic responses of maglev vehicles running on the bridges are studied for running safety and stability assessment.Moreover,the effects of track irregularity wavelength range under different amplitude and running speeds on the coupled system are investigated.The results show that the augmentation of train speed will move backward the sensitive wavelength interval,and track irregularity amplitude influences the response remarkably in the sensitive interval.

Relativistic Continuum Random Phase Approximation and Applications Ⅱ. Applications

The fully consistent relativistic continuum random phase approximation （RCRPA） has been constructed in the momentum representation in the first part of this paper. In this part we describe the numerical details for solving the Bethe-Salpeter equation. The numerical results are checked by the inverse energy weighted sum rules in the isoscalar giant monopole resonance, which are obtained from the constraint relativistic mean field theory and also calculated with the integration of the RCRPA strengths. Good agreement between them is achieved. We study the effects of the self-consistency violation, particularly the currents and Coulomb interaction to various collective multipole excitations. Using the fully consistent RCRPA method, we investigate the properties of isoscalar and isovector collective multipole excitations for some stable and exotic from light to heavy nuclei. The properties of the resonances, such as the centroid energies and strength distributions are compared with the experimental data as well as with results calculated in other models.

Dynamic Evolution with Limited Learning Information on a Small-World Network

This paper investigates the dynamic evolution with limited learning information on a small-world network.In the system, the information among the interaction players is not very lucid, and the players are not allowed to inspectthe profit collected by its neighbors, thus the focal player cannot choose randomly a neighbor or the wealthiest one andcompare its payoff to copy its strategy.It is assumed that the information acquainted by the player declines in theform of the exponential with the geographical distance between the players, and a parameter V is introduced to denotethe inspect-ability about the players.It is found that under the hospitable conditions, cooperation increases with therandomness and is inhibited by the large connectivity for the prisoner's dilemma; however, cooperation is maximal atthe moderate rewiring probability and is chaos with the connectivity for the snowdrift game.For the two games, theacuminous sight is in favor of the cooperation under the hospitable conditions; whereas, the myopic eyes are advantageousto cooperation and cooperation increases with the randomness under the hostile condition.

Quantum Monte Carlo Study of Frustrated Spin Chain under External Field

In this paper a stochastic series expansion quantum Monte Carlo algorithm is used to study a frustratedspin chain with diagonal next-nearest-neighbor interactions.The detailed balance conditions are carefully analyzed toimprove the efficiency of simulation process.As an application of this algothrim,the total magnetization,the staticstructure factor and spin-stiffness are calculated for a certain set of system parameters as a function of external fieldstrength.

The Impact of Collaborative Reading on Iranian EFL Learners Development of Reading Comprehension

This research was carried out in Iranian EFL （English as a foreign language） reading comprehension classes in an attempt to answer three research questions： （1） Does collaborative reading lead to greater comprehension of a text than private reading？; （2） If so, what strategies are used by the students during collaborative reading？; and （3） In what ways might these strategies contribute to the higher level of comprehension？. A quasi-experimental design was used to answer the first question. The participants were pre-tested and streamed into two classes of equal reading comprehension abilities. The intervention consisted of four texts of equal length, comprising two rated in a pilot study as conceptually difficult/linguistically easy, and two rated as conceptually easy/linguistically difficult. The subjects in each class were involved in reading the two types of texts collaboratively and privately for four sessions. After reading the text, the subjects were asked to answer in writing 10 comprehension questions. Collaborative reading resulted in consistently and significantly higher scores than private reading for all four texts. Qualitative methods were employed to answer the last two questions. Group interactions during collaborative reading were tape recorded and transcribed, and 10 students selected at random from the two classes were interviewed in depth. Analysis of the group interaction transcripts revealed that the participants were using five major strategies in co-constructing meaning from the texts. These strategies included brainstorming, clarifying the language, summarizing, paraphrasing, and interaction management. Other minor （i.e., infrequent） strategies were also identified, such as making PCU/NCU （positive/negative claim to understand）, eliciting confirmation, and confirming.

A Stochastic Model for Protein Synthesis and Activation through RNA-Protein Interaction in BioAmbients Calculus

Cells use various RNA （Ribonucleic Acid） regulatory mechanisms in order to temporally and coordinately influence the rate of protein synthesis. A deeper understanding of the dynamics of RNA regulation can ultimately bridge the gap between transcriptional control and protein expression. The nonlinear process of RNA-Protein Interaction （RIP）, which can be viewed as the RNA analog of the better-known chromatin immunoprecipitation application （CHIP） plays a crucial role in post-transcriptional regulation of gene expression. While ChIP identifies DNA （Deoxyribonucleic Acid） targets of DNA-binding proteins in their cellular context, RIP can be used to identify specific RNA molecules associated with specific nuclear or cytoplasmic RNA-binding proteins. In this paper, a stochastic model in BioAmbients calculus for the protein synthesis and activation through RIP process is presemed.

Superallowed Fermi transitions in RPA with a relativistic point-coupling energy functional

The self-consistent random phase approximation (RPA) approach with the residual interaction derived from a relativistic pointcoupling energy functional is applied to evaluate the isospin symmetry-breaking corrections δ c for the 0+ → 0+ superallowed Fermi transitions.With these δ c values,together with the available experimental f t values and the improved radiative corrections,the unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) matrix is examined.Even with the consideration of uncertainty,the sum of squared top-row elements has been shown to deviate from the unitarity condition by 0.1% for all the employed relativistic energy functionals.

Convergence Rate of the Asymmetric Deffuant-Weisbuch Dynamics

This paper considers the convergence rate of an asymmetric Deffuant-Weisbuch model.The model is composed by finite n interacting agents.In this model,agent i’s opinion is updated at each time,by first selecting one randomly from n agents,and then combining the selected agent j’s opinion if the distance between j’s opinion and i’s opinion is not larger than the confidence radiusε0.This yields the endogenously changing inter-agent topologies.Based on the previous result that all agents opinions will converge almost surely for any initial states,the authors prove that the expected potential function of the convergence rate is upper bounded by a negative exponential function of time t when opinions reach consensus finally and is upper bounded by a negative power function of time t when opinions converge to several different limits.

Stochastic rules for predator and prey hunting and escape behavior in a lattice-based model

Understanding of ecosystem resilience and stability requires comprehending predator- prey dynamics because ecosystems consist of dynamically interacting subsystems that include predator-prey relationships. This relationship is closely related to the hunting- escaping strategies employed by the predator and prey. Therefore, understanding the effects of hunting and escaping strategies on ecosystems will lead to a better under- standing of these systems. As an approach for describing the predator-prey interaction, lattice-based models have been adopted because this approach has strong advantages for simulating various dynamical processes of individual-individual interaction. In the models, each lattice cell is either considered as an attractive/repulsive cell, or an indi- vidual cell, or else it is empty. The attractive （or repulsive cell） can be interpreted as the prey （or predator） of the individual. These states allow us to incorporate the ecological processes of local antagonistic interactions, namely the spread of disturbances （by the predator） and regrowth or recovery （by the prey）. These processes are directly related to the strategic behavior of individuals, such as hunting and escaping. In this study, we suggest a simple and effective mapping formula as a stochastic rule to describe the hunt- ing and escaping behavior. This formula could be widely used not only in the behavior but also in competitive and cooperative relationships.