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S-wave contributions to ■→(D^0,■)π^+π^- in the perturbative QCD framework

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Chinese Physics C 2019年第7期43卷 22-30页

作者： Ye xing Zhi-peng xing INPAC SKLPPC MOE Key Laboratory for Particle Physics School of Physics and AstronomyShanghai Jiao Tong University

■→（D0,■）π+π-is induced by the b→c■s/b→u■s transitions,which can interfere if a CP-eigenstate DCP is *** interference contribution is sensitive to the CKM angle *** this work,we study the S-wave π+π-contributions to the process in the perturbative QCD *** the factorization framework,we adopt twomeson light-cone distribution amplitudes,whose normalization is parametrized by the S-wave time-like two-pion form factor with resonance contributions from f0（500）,f0（980）,f0（1500）,f0（1790）.We find that the branching ratio of ■→（D0,■）（π+π-）S is of the order of 10-6,and that significant interference exists in ■→DCP（π+π-）*** measurement could not only provide useful constraints on the CKM angle y,but would also be helpful for exploring the multi-body decay mechanism of heavy mesons.

关键词： PQCD three bodys decays γ angle

Validity of Nonlinear Thermodynamic Models in Ferroelectric-Paraelectric Bilayers and Superlattices

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Chinese Physics Letters 2012年第5期29卷 221-224页

作者： LIU Yang peng xing-Ping Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou UniversityLanzhou 730000

We examine the validity of nonlinear thermodynamic models which incorporate the contribution of electrostatic coupling and interfacial space charge in ferroelectric-paraelectric *** of the directions between build-in polarization and field is *** of ferroelectricity does not follow the variation in coupling strength between different *** addition,we observe that the field-induced polarization in the paraelectric layer deviates from the polarization derived by thermodynamic *** findings indicate that the current versions of thermodynamic models need to be modified.

关键词： theory. thermodynamic ferroelectric

Strain Effects of the Structural Characteristics of Ferroelectric Transition in Single-Domain Epitaxial BiFeO_(3) Films

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Chinese Physics Letters 2011年第6期28卷 283-286页

作者： LIU Yang peng xing-Ping The Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou UniversityLanzhou 730000

Structural characteristics of phase transition in single-domain epitaxial BiFeO_(3)films are studied by the Landau–Devonshire *** is predicted that remanent polarization shows strong strain dependence for different temperatures while spontaneous polarization is almost independent of strain over a wide temperature(0–500°C).We also obtain the thickness dependence of the c−axis lattice parameter and Curie temperature,and make a comparison between the polarization rotation angle and the angle attributed to the structural evolution in epitaxial(001)p BiFeO_(3)films grown on SrTiO_(3)*** theoretical results are in agreement with recent experimental and theoretical *** calculations show that the clamping effect should also be taken into account in order to depict the mechanism of the polarization rotation completely.

关键词： theory rotation Transition

Synthesis of a novel calix[4]arene-based fluorescent ionophore and its metal ions recognition properties

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Chinese Chemical Letters 2009年第1期20卷 13-16页

作者： Qiang peng xing Hua Tang College of Environmental and Chemical Engineering Nanchang Hangkong University Nanchang 330063 People's Republic of China

A novel fluorescent ionophore derived from calix[4]arene and pyrazoline was designed and *** molecular structure was confirmed by ^1H NMR and element *** resulting material shows specific fluorescent behavior toward the Zn^2＋ion among the other divalent metal ions,such as Co^2＋,Ni^2＋,Cu^2＋.The primary results indicate this ionophore material is a potential material for developing efficient fluorescent Zn^2＋ chemosensors.

关键词： Calixarene Pyrazoline Recognition Metal ions

Risk-based Optimal Investment and Proportional Reinsurance of an Insurer with Hidden Regime Switching

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Acta Mathematicae Applicatae Sinica 2016年第3期32卷 755-770页

作者： xing-chun peng Yi-jun HU School of Science Wuhan University of Technology School of Mathematics and Statistics Wuhan University

In this paper, we study the optimal investment and proportional reinsurance strategy for an insurer in a hidden Markov regime-switching environment. A risk-based approach is considered, where the insurer aims at selecting an optimal strategy with a view to minimizing the risk described by a convex risk measure of its terminal wealth. We solve the problem in two steps. First, we employ the filtering theory to turn the optimization problem with partial observations into one with complete observations. Second, by using BSDEs with jumps, we solve the problem with complete observations.

关键词： investment reinsurance hidden Markov chain convex risk measure backward stochastic differential equation

高校图书馆数字资源违规使用对策设计及其仿真校验

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现代情报 2025年第1期45卷 18-32页

作者：李英群裴雷朱静娴李亚菲彭星张晶南京大学信息管理学院江苏南京210023 南京大学数据智能与交叉创新实验室江苏南京210023 中国移动研究院北京100053

[目的/意义]高校图书馆数字资源违规使用治理政策涉及多方利益主体博弈,单一维度的分析视角无法从系统层面有效调和并解决这一矛盾冲突。[方法/过程]本文采用演化博弈理论框架,构建数据供应商、高校图书馆和用户的三方演化博弈模型,探... 详细信息

[目的/意义]高校图书馆数字资源违规使用治理政策涉及多方利益主体博弈,单一维度的分析视角无法从系统层面有效调和并解决这一矛盾冲突。[方法/过程]本文采用演化博弈理论框架,构建数据供应商、高校图书馆和用户的三方演化博弈模型,探究各主体的行为模式及其均衡稳定策略。通过构建层次结构模型对参数赋值,以提升仿真分析结果的可靠性和真实性。随后通过MATLAB仿真实验,剖析了各类因素对于演化博弈的影响机制与作用路径,厘清利益对象间的动态交互关系和关联结构。[结果/结论]研究结果显示,该博弈模型呈现出两种不同的演化稳定策略状态,并基于数据资源违规使用的现状,分别从三方博弈主体提出针对性的意见。

关键词：高校图书馆供应商用户数字资源合规使用违规使用政策设计演化博弈仿真分析

A pipelined Reed-Solomon decoder based on a modified step-by-step algorithm

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Frontiers of Information Technology & Electronic Engineering 2016年第9期17卷 954-961页

作者： xing-ru peng Wei ZHANG Yan-yan LIU School of Electronic and Information Engineering Tianjin UniversityTianjin 300072China College of Electronic Information and Optical Engineering Nankai UniversityTianjin 300071China

We propose a pipelined Reed-Solomon(RS) decoder for an ultra-wideband system using a modified stepby-step algorithm. To reduce the complexity, the modified step-by-step algorithm merges two cases of the original algorithm. The pipelined structure allows the decoder to work at high rates with minimum delay. Consequently, for RS(23,17) codes, the proposed architecture requires 42.5% and 24.4% less area compared with a modified Euclidean architecture and a pipelined degree-computationless modified Euclidean architecture, respectively. The area of the proposed decoder is 11.3% less than that of the previous step-by-step decoder with a lower critical path delay.

关键词： Reed-Solomon codes Step-by-step algorithm Ultra-wideband Pipelined structure

An experimental study on the impact behavior of cavitation inside tip clearance of a hydrofoil

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Journal of Hydrodynamics 2023年第6期35卷 1208-1214页

作者： Yan-tao Cao Liang-hao Xu Xiao-xing peng National Key Laboratory on Ship Vibration and Noise China Ship Scientific Research CenterWuxi214082China Taihu Laboratory of Deepsea Technological Science Wuxi214082China

Tip clearance cavitation is one of the most common cavitation phenomena exist on duct propellers,pumps and some hydraulic turbines,which may lead to erosion of the *** to the influence of the nearby wall,cavitation inside the tip clearance is more complicated than other cases without *** far,the understanding about the impact mechanism of tip clearance cavitation is still *** this paper,to obtain the impact behavior of tip clearance cavitation,a high-speed camera was used to capture the cavitation behavior inside the tip clearance of a hydrofoil,and surface paint coating peeling method was applied to show the impact *** indicated that cavitation around the tip of the hydrofoil was composed of a tip separation cavity and a tip leakage vortex cavity,and the one with contribution to impact was the tip separation *** the comprehensive analysis of the paint peeling region and dynamic behavior of tip separation cavity,the impact was found to be related to the local collapse and rebound of the cloud cavitation shed from the attached *** addition,the influence of tip clearance size on the behavior of tip clearance cavitation was also *** the tip clearance size increased,the tip separation cavity tended to transfer from sheet cavitation to vortex *** findings can provide a sound basis for evaluating the erosion risk arising from the tip clearance cavitation.

关键词： Tip clearance cavitation impact region impact behavior tip clearance size

基于PSM-DID方法的地方数字经济政策实施成效评估

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现代情报 2025年第1期45卷 33-45页

作者：李亚菲何文芊刘晓宇裴雷陈烨彭星南京大学信息管理学院江苏南京210023 南京大学数据智能与交叉创新实验室江苏南京210023 湖南省工业互联网发展研究中心湖南长沙410000 中国移动研究院北京100053

[目的/意义]数字经济政策已成为政府促进经济发展的重要政策工具,实证分析我国地方数字经济政策的实施成效,有助于推动地方经济实现高质量发展。[方法/过程]本文利用2010—2021年中国337个地级及以上城市的面板数据,采用PSM-DID方法检... 详细信息

[目的/意义]数字经济政策已成为政府促进经济发展的重要政策工具,实证分析我国地方数字经济政策的实施成效,有助于推动地方经济实现高质量发展。[方法/过程]本文利用2010—2021年中国337个地级及以上城市的面板数据,采用PSM-DID方法检验了地方数字经济政策对地区经济发展的影响。[结果/结论]地方数字经济政策能够显著促进地区经济增长,但其促进作用存在两年时滞;人口规模较大或行政等级较高的城市数字经济政策实施成效更显著;中西部地区数字经济政策对地区经济发展的促进作用超过了东部地区。

关键词：数字经济政策政策评估双重差分法倾向得分匹配地区经济增长