Collective bounce-off phenomenon in139La+Ag(Br) reaction at 1.1 A GeV energy

Out of a total statistics of 896¹³⁹La+Ag(Br) interactions, 128 interactions having multiplicity of target fragments (Z⩾1)⩾8 and projectile fragments (Z⩾2)⩾4 have been selected. They correspond to quasi-peripheral interactions. Azimuthal angle correlation between sources of target fragments (TFs) and projectile fragments (PFs) shows the existence of bounce-off effect. Using data of La+Ag(Br) and⁸⁴Kr+Ag(Br) reactions it is shown that individual helium [Z=2, PFs] and heavier fragment [Z⩾3, PFs] show different emission characteristics. Further, a two prong correlation functionT(Φ _ij ) plotted for heavier fragments and helium fragments separately, indicates the possibility of existence of different physical conditions. This observation is supported by the different momentum widths of helium fragments and heavier fragments. From the momentum width data of Kr+Ag(Br) reactions normalized density comes out to be ≈4.7. Using quasi-elastic kinematics for the bounce-off nuclei, the excitation energy has been computed from the experimental data of flow angles. The strength of bounce-off seems to decrease with the increase of excitation energy or temperature.     

税企博弈模型──防止出口骗税的一个对策

本文初步探讨了现行出口骗税行为处罚所产生的负效应，进而建立了税企博弈模型．在国家税收期望损失为零的情况下，首次提出了出口骗税罚款系数公式（L）．该公式揭示了罚款系数与检查概率之间的关系，为税务决策部门制定罚款系数及税务操作部门安排检查力量提供了理论依据．公式（L）可操作性强，具有一定的实用价值．     

传统节会的声誉溢出效应:基于Kreps-Milgrom-Roberts-Wilson声誉模型

中国经济繁荣带来传统节会复苏,但是传统节会市场的鱼龙混杂导致传统节会声誉参差不齐,该现象引起了政府部门的重视和学术界的关注.现有文献侧重于对节会概念、意义、文化层面的讨论,缺乏对节会声誉问题的研究,因此本文参考Kreps-Milgrom-Roberts-Wilson声誉模型,在四个基本假设基础上建立了传统节会的声誉模型,分析了传统节会的声誉溢出效应及均衡条件.研究发现:第一,参与者认为传统节会承办方的声誉越好,承办方选择不欺骗参与者的概率就越大,承办方建立声誉的积极性也就越高;第二,一旦承办方出现欺骗参与者的行为,参与者就会认为其是弱承办方,在下一期承办方会失去参与者的信任,从而失去长期获利的机会;第三,无论是强承办方还是弱承办方,不去欺骗参与者才是最优选择,此时承办方和参与者可以实现合作共赢,这是一种更有效率的文化旅游发展模式.因此,文章提出了建立传统节会声誉评价制度与信息公开制度、加强对传统节会的监管以及完善相关法律法规的政策建议.     

Charged Multiplicity Density and Number of Participant Nucleons in Relativistic Nuclear Collisions

The energy and centrality dependencies of charged particle pseudorapidity density in relativistic nuclearcollisions were studied using a hadron and string cascade model, JPCIAE. Both the relativistic p+p experimental dataand the PHOBOS and PHENIX Au+Au data at RHIC energy could be fairly reproduced within the framework ofJPCIAE model and without retuning the model parameters. The predictions for Pb + Pb collisions at the LHC energywere also given. We computed the participant nucleon distributions using different methods. It was found that thenumber of participant nucleons is not a well defined variable both experimentally and theoretically. Thus it may beinappropriate to use the charged particle pseudorapidity density per participant pair .as a function of the number ofparticipant nucleons for distinguishing various theoretical models.     

BOT项目运营外包时的各参与方决策分析

在BOT项目采用运营外包模式的前提下,通过建立政府、项目公司和运营商这三个参与方之间的三方博弈模型,求得了博弈的均衡解,在此基础上对他们的决策行为,以及这些行为之间的相互影响进行了探讨.另外,还分析了需求对项目产品性能的敏感性和运营商努力对项目产品性能的边际贡献率这两个因素对他们决策行为的影响.     

出口退税中的博奕

本文初步探讨了现行出口退税中,国家与企业及法人的博奕模型．它给出了对以出口骗取退税的企业的几个罚款系数（下限）公式,使企业在博奕中只能采取不骗税的策略,从而使国家税收不受损失     

事件故障状态量子博弈过程的参与者收益研究

为了解事件故障状态量子博弈过程中参与者收益随各影响因素的变化情况,提出在空间故障树(Space Fault Tree, SFT)框架内,以事件故障状态为对象,对参与者收益进行研究。事件故障状态使用量子态表示,管理者和操作者的不同行为对事件故障状态的作用使用博弈表示。考虑因素包括安全产出价值、安全收益分配系数、安全措施成本。研究了事件故障状态与量子博弈的关系;纠缠与非纠缠态下的参与者收益;参与者收益受到各因素影响的特征等。研究得到了管理者和操作者考虑纠缠和非纠缠态的收益函数。结合SFT理论方法,提出了针对收益的因素重要度、因素联合重要度、收益风险区和安全区、因素区域重要度。理论上SFT可用于量子博弈参与者收益的分析。也论述了使用因素空间理论解决该问题的可能性。     

在RHIC的极限碎裂和Φ介子产生(英文)

利用强子和串级联模型LUCIAE研究了PHOBOS的极限碎裂等以及在PHIC进行的Au+Au碰撞中带电粒子多重性的经验标度规律. 对Φ介子的产生机制也通过与带电粒子多重性的比较进行类似的研究. 结果似乎表明在串级碎裂模型中带电粒子和Φ介子有共同的产生机制. 还讨论了PHOBOS经验标度规律的模型依赖性.The PHOBOS’s limiting fragmentation etc. three empirical scaling rules for charged multiplicity in Au+Au collisions at RHIC are investigated by ahadron and string cascade model LUCIAE. Similar studies are performed for the meson exploring its production mechanism via comparing with the charged multiplicity. The LUCIAE results for charged multiplicity are compatible with PHOBOS observations. However, for the  meson the three empirical scaling rules are either kept only or kept better in the LUCIAE calculations without reduction mechanism of the s quark suppression extra introduced for the strangeness in LUCIAE model. These results seem indicating a universal production mechanism for charged particle and  meson in string fragmentation regime. It is discussed that the PHOBOS’s empirical scaling rules are model dependent indeed.     

Excitation Functions of Tsallis-Like Parameters in High-Energy Nucleus–Nucleus Collisions

The transverse momentum spectra of charged pions, kaons, and protons produced at mid-rapidity in central nucleus–nucleus (AA) collisions at high energies are analyzed by considering particles to be created from two participant partons, which are assumed to be contributors from the collision system. Each participant (contributor) parton is assumed to contribute to the transverse momentum by a Tsallis-like function. The contributions of the two participant partons are regarded as the two components of transverse momentum of the identified particle. The experimental data measured in high-energy AA collisions by international collaborations are studied. The excitation functions of kinetic freeze-out temperature and transverse flow velocity are extracted. The two parameters increase quickly from ≈3 to ≈10 GeV (exactly from 2.7 to 7.7 GeV) and then slowly at above 10 GeV with the increase of collision energy. In particular, there is a plateau from near 10 GeV to 200 GeV in the excitation function of kinetic freeze-out temperature.