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Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： song He li li Sai Wang Shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

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紫外光空分复用自组织网络路由协议

中国激光 2017年第10期44卷 187-196页

作者：宋晓梅宋菲宋鹏李云红西安工程大学电子信息学院陕西西安710048 陕西省复杂系统控制与智能信息处理重点实验室陕西西安710048

为了改善紫外光(UV)点对点通信中传输距离有限、覆盖范围小的问题,组建了UV自组织(Ad Hoc)网络。结合UV通信的信道特性,提出了一种UV组网通信收发装置设计方案。基于该方案,给出了UV Ad Hoc网络节点定位算法,该算法利用节点间的通信距... 详细信息

为了改善紫外光(UV)点对点通信中传输距离有限、覆盖范围小的问题,组建了UV自组织(Ad Hoc)网络。结合UV通信的信道特性,提出了一种UV组网通信收发装置设计方案。基于该方案,给出了UV Ad Hoc网络节点定位算法,该算法利用节点间的通信距离和扇区信息求得节点间的相对位置。以无线Ad Hoc网络多播按需距离矢量路由协议为基础,提出了一种UV空分复用Ad Hoc网络路由协议,并对该路由协议进行了仿真,给出了不同节点数和运动区域下的仿真结果。结果表明:在满足发包数、时延和丢包率等通信要求的前提下,在一定运动区域内,应选择较少的节点;当节点数一定时,应选择较小的运动区域。

关键词：光通信紫外光通信自组织网络空分复用节点定位路由

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感潮河段水位过程预报探讨

水科学进展 2000年第3期11卷 302-306页

作者：宋立松魏高峰浙江省钱塘江管理局浙江杭州310016 浙江省水利疏浚工程处浙江湖州313000

感潮河段水位过程同时受径流、潮流影响 ,其预报较为困难。将水位过程视为时间序列 ,用不同的模型进行了预报比较 ,认为以潮汐作用为主的水位预报可采用神经网络模型 ,对高水位预报可采用 ARMA(2 ,1)模型 ,而对洪水作用为主的河道。

关键词：神经网络时间序列感潮河段水位预报

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曹娥江低潮位序列突变成份分析

泥沙研究 2000年第1期25卷 69-72页

作者：宋立松浙江省钱塘江管理局浙江杭州310016

本文提出了动态分维数的计算方法，并应用此方法对曹娥江低潮位序列中的突变成份进行了分析。结果表明，文中所用的方法对识别人为或自然因素引起的潮位时间序列中的突变成份是有效的，具有一定的实用价值。

关键词：动态分维数时间序列河床演变曹娥江低潮位

An efficient quantum proactive incremental learning algorithm

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 49-57页

作者： lingxiao li Jing li Yanqi song Sujuan Qin Qiaoyan Wen Fei Gao State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications School of Cyberspace Security Beijing University of Posts and Telecommunications

In scenarios where a large amount of data needs to be learned, incremental learning can make full use of old knowledge, significantly reduce the computational cost of the overall learning process, and maintain high performance. In this paper, taking the MaxCut problem as our example, we introduce the idea of incremental learning into quantum computing, and propose a Quantum Proactive Incremental Learning algorithm(QPIL). Instead of a one-off training of quantum circuit, QPIL contains a multi-phase training on gradually-increased subgraphs of all vertices, proactively reducing large-scale problems to smaller ones to solve in steps, providing an efficient solution for MaxCut. Specifically, some vertices and corresponding edges are randomly selected for training to obtain optimized parameters of the quantum circuit at first. Then, in each incremental phase, the remaining vertices and corresponding edges are gradually added and the parameters obtained from the previous phase are reused in the parameter initialization of the current phase. We perform experiments on 120 different small-scale graphs, and it shows that QPIL performs superior to prevalent quantum and classical baselines in terms of approximation ratio(AR), time cost, anti-forgetting, and solving stability. In particular, QPIL's AR surpasses 20% of mainstream quantum baselines, and the time cost is less than 1/5 of them. The idea of QPIL is expected to inspire efficient and high-quality solutions in large-scale Max Cut and other combinatorial optimization problems.

关键词： variational quantum algorithm incremental learning multi-phase training MaxCut quantum computing

Passive activity enhances residual control ability in patients with complete spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2337-2347页

作者： Yanqing Xiao Mingming Gao Zejia He Jia Zheng Hongming Bai Jia-Sheng Rao Guiyun song Wei song Xiaoguang li Beijing Key Laboratory for Biomaterials and Neural Regeneration Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijingChina Department of Rehabilitation Evaluation China Rehabilitation Research CenterBeijingChina Cardiac Center Beijing Children’s HospitalCapital Medical UniversityBeijingChina The State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijingChina Department of Rehabilitation Engineering China Rehabilitation Science InstituteBeijingChina

Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury ***,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface *** this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord *** patients with chronic complete thoracic spinal cord injury were *** electromyography data from eight major leg muscles were acquired and compared before and after the passive activity *** results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of *** the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically *** findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury.

关键词： complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task

Repetitive traumatic brain injury–induced complement C1–related inflammation impairs long-term hippocampal neurogenesis

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Neural Regeneration Research 2025年第3期20卷 821-835页

作者： Jing Wang Bing Zhang Lanfang li Xiaomei Tang Jinyu Zeng Yige song Chao Xu Kai Zhao Guoqiang liu Youming Lu Xinyan li Kai Shu Department of Neurosurgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Neurosurgery Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Pathophysiology School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Institute for Brain Research Wuhan Center of Brain ScienceHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Graduate Student Chongqing Medical UniversityChongqingChina Department of Basic Medicine School of Medical ScienceHubei University for NationalitiesEnshiHubei ProvinceChina Department of Anatomy School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Repetitive traumatic brain injury impacts adult neurogenesis in the hippocampal dentate gyrus,leading to long-term cognitive ***,the mechanism underlying this neurogenesis impairment remains *** this study,we established a male mouse model of repetitive traumatic brain injury and performed long-term evaluation of neurogenesis of the hippocampal dentate gyrus after repetitive traumatic brain *** results showed that repetitive traumatic brain injury inhibited neural stem cell proliferation and development,delayed neuronal maturation,and reduced the complexity of neuronal dendrites and *** with repetitive traumatic brain injuryalso showed deficits in spatial memory ***,following repetitive traumatic brain injury,neuroinflammation was enhanced in the neurogenesis microenvironment where C1q levels were increased,C1q binding protein levels were decreased,and canonical Wnt/β-catenin signaling was *** inhibitor of C1 reversed the long-term impairment of neurogenesis induced by repetitive traumatic brain injury and improved neurological *** findings suggest that repetitive traumatic brain injury–induced C1-related inflammation impairs long-term neurogenesis in the dentate gyrus and contributes to spatial memory retrieval dysfunction.

关键词： complement C1 dendrite dentate gyrus hippocampus neural stem cell neurogenesis neuroinflammation neurological function neuron traumatic brain injury

Approximate Strong Equilibrium in Load Balancing Games

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Approximate Strong Equilibrium in Load Balancing Games

中国企业运筹学第七届学术年会暨山东省运筹学会学术会议

作者： song-song li Yu-Zhong Zhang School of Management,Qufu Normal University,Rizhao 276826,Shandong,China

In this paper,we consider approximate strong equilibrium in the load balancing games with identical *** load balancing games,every job chooses one of the servers,and each job wishes to minimize its cost,given by the workload of the server it is assigned to.A Nash equilibrium（NE） is a strategy profile that is resilient to unilateral *** an NE in this game is ***,NE-configurations are not stable against coordinated deviations of several jobs.A strong Nash equilibrium（SE） is one that is stable against coordinated deviations of any *** will evaluate how well a NE-configuration approximates *** any job assignment in a load balancing game,the improvement ratio（IR） of a deviation of a job is defined as the ratio between the pre-and post-deviation *** NE is said to be a ρ-approximate SE（ρ≥1） if there is no coalition of jobs such that each job of the coalition will have an IR more than ρ from coordinated deviations of the *** this paper,we prove,for load balancing games of up to 8 servers,any NE assignment is a 5/4 approximate SE,and the bound is ***,it is a（3 2 - 2m-3 2（m-1） 2）-approximate SE if the game has m（m≥9） servers.

关键词： Nash equilibrium load balancing approximation

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杭州湾悬浮泥沙浓度垂向分布规律分析与模拟

浙江大学学报（工学版） 2008年第11期42卷 2028-2032页

作者：王繁周斌徐建明宋立松王新浙江大学环境与资源学院浙江杭州310029 杭州师范大学生命与环境科学学院浙江杭州310012 浙江省水利河口研究院浙江杭州310020

从遥感监测应用的角度考虑,针对杭州湾的复杂水动力特点,把影响泥沙再悬浮的水流紊动扩散机理概化为宏观上容易表达的潮动力因素,在分析垂向各层悬浮泥沙浓度(SSC)相关性的基础上,选取水体近表层(0.2H)处SSC和水深、流速、潮情、潮时作... 详细信息

从遥感监测应用的角度考虑,针对杭州湾的复杂水动力特点,把影响泥沙再悬浮的水流紊动扩散机理概化为宏观上容易表达的潮动力因素,在分析垂向各层悬浮泥沙浓度(SSC)相关性的基础上,选取水体近表层(0.2H)处SSC和水深、流速、潮情、潮时作为模型输入因子,垂向平均SSC作为模型输出因子,运用Levenberg-Marguardt优化算法对输入因子进行优化,建立了反向传播(BP)神经网络模型,对杭州湾澉浦断面的SSC垂向分布规律进行了模拟.结果表明,潮动力变化对水体各层SSC影响显著,各层SSC与平均SSC均出现对应的涨落波动规律;在不同潮情下SSC垂向分布均表现出比较明显的相关性,相邻各层SSC相关性显著,其中表层SSC与垂向平均SSC相关系数均达到0.8以上;BP神经网络模型应用于SSC垂向分布规律预测的性能指数(PI)为0.04,分别低于两类线性模型的0.06和0.07,其预测性能高于线性模型.

关键词：神经网络悬浮泥沙浓度垂向分布杭州湾