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Model-free conditional independence feature screening for ultrahigh dimensional data

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Science China Mathematics 2017年第3期60卷 551-568页

作者： wang luheng LIU JingYuan LI Yong LI RunZe School of Mathematics Beijing Normal University Beijing 100875 China Department of Statistics School of Economics Wang Yanan Institute for Studies in Economics and Fujian Key Laboratory of Statistical Science Xiamen University Xiamen 361005 China School of Statistics Beijing Normal University Beijing 100875 China Department of Statistics and the Methodology Center Pennsylvania State University University Park PA 16802-2111 USA

Feature screening plays an important role in ultrahigh dimensional data *** paper is concerned with conditional feature screening when one is interested in detecting the association between the response and ultrahigh dimensional predictors(e.g.,genetic makers)given a low-dimensional exposure variable(such as clinical variables or environmental variables).To this end,we first propose a new index to measure conditional independence,and further develop a conditional screening procedure based on the newly proposed *** systematically study the theoretical property of the proposed procedure and establish the sure screening and ranking consistency properties under some very mild *** newly proposed screening procedure enjoys some appealing properties.(a)It is model-free in that its implementation does not require a specification on the model structure;(b)it is robust to heavy-tailed distributions or outliers in both directions of response and predictors;and(c)it can deal with both feature screening and the conditional screening in a unified *** study the finite sample performance of the proposed procedure by Monte Carlo simulations and further illustrate the proposed method through two real data examples.

关键词： feature screening conditional feature screening high-dimensional data variable selection

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一种结合各类同化算法的一般方法

北京师范大学学报（自然科学版） 2016年第2期52卷 127-133页

作者：王禄恒李勇北京师范大学数学科学学院北京100875 北京师范大学统计学院北京100875

提出了一个将不同滤波方法的估计结果相结合的一般框架,进而得到一个更加稳健的估计结果.首先,将不同方法的预报集合(粒子)结合,并通过相应的统计方法去掉集合中对状态估计贡献非常小的粒子.然后,我们使用处理过的集合样本,利用核密度估... 详细信息

提出了一个将不同滤波方法的估计结果相结合的一般框架,进而得到一个更加稳健的估计结果.首先,将不同方法的预报集合(粒子)结合,并通过相应的统计方法去掉集合中对状态估计贡献非常小的粒子.然后,我们使用处理过的集合样本,利用核密度估计(KDE)得到相应的试验密度(proposal distribution),并从该密度中重新抽样,最后利用贝叶斯滤波方法得到新的估计值.由于不同数据同化方法都有相应的适用范围,新方法的估计结果可以结合各类方法的优点,进而得到一个更加稳健的估计结果。在模拟试验中,我们用集合Kalman滤波(EnKF)与粒子滤波(PF)的集合样本来估计试验分布,从模拟结果可以看出,新方法可以较大的提高原有方法的估计精度,并有效的预防了滤波发散.

关键词：状态空间模型数据同化集合Kalman滤波粒子滤波

“出圈”与“出海”:在线视频产业发展动态与功能性转变

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艺术评论 2021年第12期 54-64页

作者：王立新王璐珩重庆大学美视电影学院重庆大学城市化与区域创新极发展研究中心学术团队重庆大学文化创意产业研究院

自新型冠状病毒肺炎疫情在全球爆发以来,疫情波及地区线下文化产业遭受很大冲击,但线上数字文化产业因其技术特性反而呈现旺盛增势,在线视频产业的增速发展表现更为突出。在迅速增长的线上消费业态助力下,在线视频产业平台目标消费人群... 详细信息

自新型冠状病毒肺炎疫情在全球爆发以来,疫情波及地区线下文化产业遭受很大冲击,但线上数字文化产业因其技术特性反而呈现旺盛增势,在线视频产业的增速发展表现更为突出。在迅速增长的线上消费业态助力下,在线视频产业平台目标消费人群、社会影响力辐射人群从以青少年为主,扩大至不同代际的年龄圈层。在线视频产业开始关注传统线下转线上的新用户群体的文化消费倾向。更为明晰的功能性分区、去同质化与在地化的内容生产和营销策略成为各头部在线视频平台不约而同的着力方向。本文尝试以在线视频产业[1]的传统网剧视频头部平台,新型流量品牌视频平台和短视频[2]平台的突出代表为例,梳理、探讨在线视频产业的功能性转变与未来文化消费业态发展趋势。

关键词：数字文化产业在线视频产业去同质化在地化代际文化圈层

基于萨道夫斯基回归模型的爆破质点振动速度分析方法

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红水河 2023年第3期42卷 114-118页

作者：徐洋王路恒中国电建集团贵阳勘测设计研究院有限公司贵州贵阳550081

笔者基于萨道夫斯基回归模型,对某水电站生态供水洞爆破开挖过程中的质点振动监测数据进行分析。通过对数据的处理和建模,得出影响质点振动速度的主要因素,建立准确的振动预测模型。经实际监测数据验证,证明了模型的可靠性和适用性。该... 详细信息

笔者基于萨道夫斯基回归模型,对某水电站生态供水洞爆破开挖过程中的质点振动监测数据进行分析。通过对数据的处理和建模,得出影响质点振动速度的主要因素,建立准确的振动预测模型。经实际监测数据验证,证明了模型的可靠性和适用性。该研究成果对于爆破开挖工程的安全控制及爆破振动判据有着重要意义,可为爆破开挖施工提供理论依据。

关键词：萨道夫斯基回归模型爆破开挖爆破振动质点振动速度

基于大气CO2浓度和生态碳通量模型的土壤碳库优化方法

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科学通报 2015年第13期60卷 1227-1234页

作者：黄文贤李勇陈镜明王禄恒郑珩崔艳宽北京师范大学统计学院北京100875 南京大学国际地球系统科学研究所南京210093 Department of Geography and Program in Planning University of Toronto Toronto M5S 3G3Canada

在碳循环过程中,土壤有机碳库的大小和分布对于基于过程的生态系统模型至关重要.由于全球地表土壤有机碳含量直接观测数据分辨率极为稀疏,基于这些数据所得的区域土壤有机碳库分布存在极大的误差.大气二氧化碳(CO2)浓度和土壤有机碳库... 详细信息

在碳循环过程中,土壤有机碳库的大小和分布对于基于过程的生态系统模型至关重要.由于全球地表土壤有机碳含量直接观测数据分辨率极为稀疏,基于这些数据所得的区域土壤有机碳库分布存在极大的误差.大气二氧化碳(CO2)浓度和土壤有机碳库是生态碳循环的重要组成部分,利用CO2浓度和生态碳循环模型修正土壤有机碳库,是改进碳库估计的新途径.本文通过大气CO2传输模型和陆地生态碳通量模型,建立CO2浓度和土壤有机碳库之间的关系,获得了修正土壤有机碳库的方法.应用实例分析结果表明:该方法可以有效修正土壤有机碳库,明显改进陆地生态通量模型模拟效果.

关键词：土壤有机碳库 CO2浓度大气传输模型生态碳通量模型双优化方法

An Iterated Greedy Algorithm with Memory and Learning Mechanisms for the Distributed Permutation Flow Shop Scheduling Problem

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Computers, Materials & Continua 2025年第1期82卷 371-388页

作者： Binhui wang Hongfeng wang College of Information Science and Engineering Northeastern UniversityShenyang110819China

The distributed permutation flow shop scheduling problem(DPFSP)has received increasing attention in recent *** iterated greedy algorithm(IGA)serves as a powerful optimizer for addressing such a problem because of its straightforward,single-solution evolution ***,a potential draw-back of IGA is the lack of utilization of historical information,which could lead to an imbalance between exploration and exploitation,especially in large-scale *** a consequence,this paper develops an IGA with memory and learning mechanisms(MLIGA)to efficiently solve the DPFSP targeted at the ***,we incorporate a memory mechanism to make a more informed selection of the initial solution at each stage of the search,by extending,reconstructing,and reinforcing the information from previous *** addition,we design a twolayer cooperative reinforcement learning approach to intelligently determine the key parameters of IGA and the operations of the memory ***,to ensure that the experience generated by each perturbation operator is fully learned and to reduce the prior parameters of MLIGA,a probability curve-based acceptance criterion is proposed by combining a cube root function with custom *** last,a discrete adaptive learning rate is employed to enhance the stability of the memory and *** ablation experiments are utilized to verify the effectiveness of the memory mechanism,and the results show that this mechanism is capable of improving the performance of IGA to a large ***,through comparative experiments involving MLIGA and five state-of-the-art algorithms on 720 benchmarks,we have discovered that MLI-GA demonstrates significant potential for solving large-scale *** indicates that MLIGA is well-suited for real-world distributed flow shop scheduling.

关键词： Distributed permutation flow shop scheduling makespan iterated greedy algorithm memory mechanism cooperative reinforcement learning

Quickly obtaining densely dispersed coherent particles in steel matrix and its related mechanical property

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 111-118页

作者： Xiaoxiao wang Qingsong Huang School of Chemical Engineering Sichuan UniversityChengdu 610065China

Densely distributed coherent nanoparticles(DCN)in steel matrix can enhance the work-hardening ability and ductility of steel *** the routes to this end can be generally classified into the liquid-solid route and the solid-solid ***,the formation of DCN structures in steel requires long processes and complex *** far,obtaining steel with coherent particle enhancement in a short time remains a bottleneck,and some necessary steps remain ***,we show a high-efficiency liquid-phase refining process reinforced by a dynamic magnetic ***-Y-Mn-O particles had an average size of around(3.53±1.21)nm and can be obtained in just around 180 *** small nanoparticles were coherent with the matrix,implying no accumulated dislocations between the particles and the steel *** findings have a potential application for improving material machining capacity,creep resistance,and radiation resistance.

关键词： ferritic steels coherent particles microstructure compression test work hardening

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

Efficient and Stable Photoassisted Lithium‑Ion Battery Enabled by Photocathode with Synergistically Boosted Carriers Dynamics

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Nano-Micro Letters 2025年第3期17卷 440-454页

作者： Zelin Ma Shiyao wang Zhuangzhuang Ma Juan Li Luomeng Zhao Zhihuan Li Shiyuan wang Yazhou Shuang Jiulong wang Fang wang Weiwei Xia Jie Jian Yibo He Junjie wang Pengfei Guo Hongqiang wang State Key Laboratory of Solidification Processing Center for Nano Energy MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical University and Shaanxi Joint Laboratory of Graphene(NPU)Xi’an 710072People’s Republic of China State Key Laboratory of Solidification Processing School of Materials Science and Engineering DepartmentNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China Research and Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063People’s Republic of China Key Laboratory of Applied Surface and Colloid Chemistry Shaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy TechnologySchool of Materials Science and EngineeringNational Ministry of EducationShaanxi Normal UniversityXi’an 710119People’s Republic of China

Efficient and stable photocathodes with versatility are of significance in photoassisted lithium-ion batteries(PLIBs),while there is always a request on fast carrier transport in electrochemical active *** work proposes a general approach of creating bulk heterojunction to boost the carrier mobility of photocathodes by simply laser assisted embedding of plasmonic *** employed in PLIBs,it was found effective for synchronously enhanced photocharge separation and transport in light charging ***,experimental photon spectroscopy,finite difference time domain method simulation and theoretical analyses demonstrate that the improved carrier dynamics are driven by the plasmonic-induced hot electron injection from metal to TiO_(2),as well as the enhanced conductivity in TiO2 matrix due to the formation of oxygen vacancies after Schottky *** from these merits,several benchmark values in performance of TiO2-based photocathode applied in PLIBs are set,including the capacity of 276 mAh g^(−1)at 0.2 A g^(−1)under illumination,photoconversion efficiency of 1.276%at 3 A g^(−1),less capacity and Columbic efficiency loss even through 200 *** results exemplify the potential of the bulk heterojunction strategy in developing highly efficient and stable photoassisted energy storage systems.

关键词： Photoassisted lithium-ion batteries Bulk heterojunction Carrier dynamics TiO2 nanofiber Plasmonic metal nanocrystals