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Ti_(3)C_(2)T_(x) MXene-mediating near-and long-range electronic effect on atomically dispersed Co for efficient lithium-sulfur batteries
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作者 Haiyan Wang Hucheng Zhang +6 位作者 Lijing Wang Yonghui Li Tianhao Zhang Zhansheng Lu Hao Jiang Chunzhong Li Jianji Wang 《Chinese Chemical Letters》 2025年第10期599-606,共8页
Sluggish sulfur conversion kinetics pose an ongoing challenge in lithium-sulfur batteries(LSBs).Here,we present a solution through far-reaching long-range electronic regulation(LRER)on single-atom active sites.N-doped... Sluggish sulfur conversion kinetics pose an ongoing challenge in lithium-sulfur batteries(LSBs).Here,we present a solution through far-reaching long-range electronic regulation(LRER)on single-atom active sites.N-doped carbons(Co-NC)are implanted with densely-distributed Co single atoms,and supported on Ti_(3)C_(2)T_(x)MXene substrates to assemble 3D Co-NC/MXene catalyst.MXene effectively mediates interlayer charge transfer(~0.70|e|)contrasted with popular carbon materials(~0.06|e|)to produce LRER through surrounding carbon atoms.The synergy of LRER with near-range electronic regulation(NRER)tunes electronic structures,and enhances heterostructural stability,thus provoking desirous catalytic kinetics of Co single atoms in sulfur reduction.Thereby,the Co-NC/MXene/S cathodes exhibit impressive rate performance and excellent cycling stability(only 0.015%capacity decay per cycle over 600 cycles at 4 C)in LSBs,surpassing state-of-the-art sulfur cathodes.This work reveals the importance of LRER for improved catalysis,and provides new guidance to tailor heterostructures to achieve high-efficient catalysts in various process. 展开更多
关键词 Single-atom sites MXene HETEROSTRUCTURE long-range electronic regulation Lithium-sulfur batteries
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New insights into the long-range interaction mechanism of nitrogen reduction
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作者 Yumeng Cheng Wei Chen +1 位作者 Cheng He Wenxue Zhang 《Journal of Energy Chemistry》 2025年第7期842-851,共10页
Catalysts with asymmetric coordination exhibit excellent electrocatalytic activity due to changes in the active sites,which affect the arrangement of reactants and catalytic activity/selectivity.Hence,the exploration ... Catalysts with asymmetric coordination exhibit excellent electrocatalytic activity due to changes in the active sites,which affect the arrangement of reactants and catalytic activity/selectivity.Hence,the exploration of the inherent characteristics of active sites within diverse coordination environments holds great significance for the experimental design of catalytic structures.Single-atom catalysts(SACs)characterized by high coordination with four carbons(26 candidates)and low coordination with dinitrogen(27candidates)are constructed using nitrogen-doped graphdiyne derivatives(NGDY)as the substrate.Additionally,5 species of dual-atom catalysts(DACs)with coexistence of both high and low coordination sites are also developed and their nitrogen reduction reaction(NRR)activities are systematically investigated by density functional theory.The results indicate that metals with low coordination exhibit superior catalytic performance,such as Mo^(L)-NGDY(U_(L)=-0.30 V)and Nb^(L)-NGDY(U_(L)=-0.32 V).Furthermore,machine learning(ML)methods have deeply analyzed and elucidated the primary intrinsic characteristics that influence catalytic performance.These results not only unveil the underlying mechanisms behind the exceptional catalytic performance exhibited by low-coordination metal atoms,but also provide relevant and significant descriptors.More importantly,based on an investigation of the catalytic activity of a series of DACs,the“buffer and low-coordination accumulate”asymmetric coordination mechanism is proposed to unveil the long-range interactions between low and high coordination atoms.Due to this remote communication,MoNb-NGDY(U_(L)=-0.09/-0.37 V)exhibits the best NRR activity.This mechanism provides valuable insights into the origin of long-range bipartite interactions and inspires the design and synthesis of NRR catalysts with different coordination environments. 展开更多
关键词 Nitrogen reduction Asymmetric coordination DAC Machine learning long-range interactions
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Long-Range Admixture Linkage Disequilibrium and Allelic Responses of Sub1 and TPP7 under Consecutive Stress in Rice Validated Through Mendelian Randomization
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作者 Sabarinathan SELVARAJ Parameswaran CHIDAMBARANATHAN +8 位作者 Goutam Kumar DASH Priyadarsini SANGHAMITRA Kishor Pundlik JEUGHALE Cayalvizhi BALASUBRAMANIASAI Devraj LENKA Basavantraya Navadagi DEVANNA Seenichamy Rathinam PRABHUKARTHIKEYAN Sanghamitra SAMANTARAY Amaresh Kumar NAYAK 《Rice science》 2025年第5期704-716,I0095-I0117,共36页
Consecutive stresses,such as initial submergence during germination followed by water deficit during the seedling stage,pose significant challenges to direct-seeded rice cultivation.By Linkage disequilibrium analysis,... Consecutive stresses,such as initial submergence during germination followed by water deficit during the seedling stage,pose significant challenges to direct-seeded rice cultivation.By Linkage disequilibrium analysis,Sub1 and Dro1(Δbp:10 Mb),as well as Sub1 and TPP7(Δbp:6 Mb)were identified to exhibit long-range linkage disequilibrium(LRLD).Meta-QTL analysis further revealed that Sub1 and TPP7 co-segregated for tolerance to submergence at the germination and seedling stages.Based on this,we hypothesized that LRLD might influence plant responses to consecutive stresses.To test this hypothesis,we developed a structured recombinant inbred line population from a cross between Bhalum 2 and Nagina 22,with alleles(Sub1 and TPP7)in linkage equilibrium.Mendelian randomization analysis validated that the parental alleles,rather than the recombinant alleles of Sub1 and TPP7,significantly influenced 13 out of 41 traits under consecutive stress conditions.Additionally,16 minor additive effect QTLs were detected between the genomic regions,spanning Sub1 and TPP7 for various traits.A single allele difference between these genomic regions enhanced crown root number,root dry weight,and specific root area by 11.45%,15.69%,and 33.15%,respectively,under flooded germination conditions.Candidate gene analysis identified WAK79 and MRLK59 as regulators of stress responses during flooded germination,recovery,and subsequent water deficit conditions.These findings highlight the critical role of parental allele combinations and genomic regions between Sub1 and TPP7 in regulating the stress responses under consecutive stresses.Favourable haplotypes derived from these alleles can be utilized to improve stress resilience in direct-seeded rice. 展开更多
关键词 anaerobic germination consecutive stress long-range linkage disequilibrium RICE water deficit Mendelian randomization
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The Relationship between Mobile Phone Dependency and Academic Burnout in Middle and High School Students
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作者 Miao Wang Meng lin Zhao +3 位作者 Dangyang Ma Xinyu Ji Donghe Li Zhansheng Xu 《International Journal of Mental Health Promotion》 2025年第8期1165-1180,共16页
Background:With the proliferation of smartphones,adolescent mobile phone dependency has intensified,potentially precipitating academic burnout and other adverse outcomes among students.Contemporary study mostly examin... Background:With the proliferation of smartphones,adolescent mobile phone dependency has intensified,potentially precipitating academic burnout and other adverse outcomes among students.Contemporary study mostly examines college populations,resulting in a lack of exploration on the internal mechanisms connecting mobile phone dependency to academic burnout.In addition to analysing the chain-mediated effects of sleep quality and cognitive flexibility,this study sought to provide theoretical insights for prevention by applying the Conservation of Resources theory to examine the relationship between academic burnout and mobile phone dependency among middle and high school students.Methods:A cluster convenience sampling approach was adopted.Data were collected from 811 middle and high school students in Tianjin,China,using a paper-based questionnaire battery comprising the Mobile Phone Addiction Index,the Pittsburgh Sleep Quality Index,the Cognitive Flexibility Scale,and the Adolescent Academic Burnout Scale.Descriptive statistics and correlation analyses were conducted using SPSS 25.0.Chain mediation effects were examined via the PROCESS macro,with significance assessed using bias-corrected bootstrap 95%confidence intervals.Results:A statistically significant positive link exists between mobile phone dependency and academic burnout among middle and high school students(r=0.575,p<0.001).Dependence on mobile phones had a substantial direct impact on academic burnout(β=0.303,p<0.001).Chain mediation analysis revealed that mobile phone dependency had a substantial direct impact on academic burnout(β=0.303,p<0.001).Sleep quality and cognitive flexibility mediated the link between mobile phone dependency and academic burnout.These indirect pathways represent 44.18%of the total effect.Conclusions:Mobile phone dependency contributes to academic burnout amongmiddle and high school students,mediated sequentially by sleep quality and cognitive flexibility.These findings suggest a potential intervention strategy to mitigate academic burnout by targeting excessive mobile phone use,enhancing sleep hygiene,and implementing cognitive flexibility training. 展开更多
关键词 Academic burnout cognitive flexibility mobile phone dependency student development sleep quality
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STDNet:Improved lip reading via short-term temporal dependency modeling
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作者 Xiaoer WU Zhenhua TAN +1 位作者 Ziwei CHENG Yuran RU 《虚拟现实与智能硬件(中英文)》 2025年第2期173-187,共15页
Background Lip reading uses lip images for visual speech recognition.Deep-learning-based lip reading has greatly improved performance in current datasets;however,most existing research ignores the significance of shor... Background Lip reading uses lip images for visual speech recognition.Deep-learning-based lip reading has greatly improved performance in current datasets;however,most existing research ignores the significance of short-term temporal dependencies of lip-shape variations between adjacent frames,which leaves space for further improvement in feature extraction.Methods This article presents a spatiotemporal feature fusion network(STDNet)that compensates for the deficiencies of current lip-reading approaches in short-term temporal dependency modeling.Specifically,to distinguish more similar and intricate content,STDNet adds a temporal feature extraction branch based on a 3D-CNN,which enhances the learning of dynamic lip movements in adjacent frames while not affecting spatial feature extraction.In particular,we designed a local–temporal block,which aggregates interframe differences,strengthening the relationship between various local lip regions through multiscale convolution.We incorporated the squeeze-and-excitation mechanism into the Global-Temporal Block,which processes a single frame as an independent unitto learn temporal variations across the entire lip region more effectively.Furthermore,attention pooling was introduced to highlight meaningful frames containing key semantic information for the target word.Results Experimental results demonstrated STDNet's superior performance on the LRW and LRW-1000,achieving word-level recognition accuracies of 90.2% and 53.56%,respectively.Extensive ablation experiments verified the rationality and effectiveness of its modules.Conclusions The proposed model effectively addresses short-term temporal dependency limitations in lip reading,and improves the temporal robustness of the model against variable-length sequences.These advancements validate the importance of explicit short-term dynamics modeling for practical lip-reading systems. 展开更多
关键词 Lip reading Spatio-temporal feature fusion Short-term temporal dependency modeling
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DockDepend:一种Dockerfile指令行依赖关系抽取方法
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作者 陈铁明 钟云锦 +2 位作者 朱志凌 王婷 宋琪杰 《小型微型计算机系统》 北大核心 2025年第10期2478-2486,共9页
针对Dockerfile指令行间依赖关系判断精度差、效率低的问题,提出了Dockerfile指令行依赖关系抽取方法DockDepend.通过数据处理模块抽取各指令行的特征信息,转换为统一的Meta特征结构,结合覆盖全指令组合的依赖判定规则,DockDepend可实... 针对Dockerfile指令行间依赖关系判断精度差、效率低的问题,提出了Dockerfile指令行依赖关系抽取方法DockDepend.通过数据处理模块抽取各指令行的特征信息,转换为统一的Meta特征结构,结合覆盖全指令组合的依赖判定规则,DockDepend可实现精准高效的依赖关系判断.实验结果表明,DockDepend的精准度显著优于基于关键词匹配方法和基于大语言模型的方法,平均准确率提升64.02%和44.17%.同时,DockDepend在处理效率方面明显优于人工手动标注和大语言模型,对于不同长度的Dockerfile解析速度均稳定在秒级.DockDepend实现了精准高效的Dockerfile指令行间依赖关系抽取,为Docker构建过程的优化和自动化提供了有力的技术支持. 展开更多
关键词 Dockerfile 依赖判断 语义补充 AST分析 特征提取
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Evolution of the rare earth trade network:A perspective of dependency and competition 被引量:1
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作者 Jilan Xu Jiahao Li +1 位作者 Vincent Charles Xin Zhao 《Geoscience Frontiers》 SCIE CAS CSCD 2024年第3期183-191,共9页
As a global strategic reserve resource,rare earth has been widely used in important industries,such as military equipment and biomedicine.However,existing analyses based solely on the total volume of rare earth trade ... As a global strategic reserve resource,rare earth has been widely used in important industries,such as military equipment and biomedicine.However,existing analyses based solely on the total volume of rare earth trade fail to uncover the underlying competition and dependency dynamics.To address this gap,this paper employs the principles of trade preference and import similarity to construct dependency and competition networks.Complex network analysis is then employed to study the evolution of the global rare earth trade network from 2002 to 2018.The main conclusions are as follows.The global rare earth trade follows the Pareto principle,and the trade network shows a scale-free distribution.China has emerged as the world’s largest importer and exporter of rare earth since 2017.In the dependency network,China has become the most dependent country since 2006.The result of community division shows that China has separated from the American community and formed new communities with the Association of Southeast Asian Nations(ASEAN)countries.The United States of America has formed a super-strong community with European and Asian countries.In the competition network,the distribution of competition intensity follows a scale-free distribution.Most countries face low-intensity competition,but there are numerous competing countries.The competition related to China has increased significantly.Lastly,the competition source for the United States of America has shifted from Mexico to China,resulting in China,the USA,and Japan becoming the core participants in the competition network. 展开更多
关键词 Rare earth Trade network dependency COMPETITION Complex network analysis
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Existence of long-range magnetic order in Heisenberg spin nanoribbons with edge modification
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作者 Da-cheng Ma Ling-yi Cui +3 位作者 Chu-xiao Sun Xiao-dan Chi Zheng-Nan XianYu An Du 《Communications in Theoretical Physics》 SCIE CAS CSCD 2024年第7期134-144,共11页
Long-range magnetic order appears on a side decorated Heisenberg spin nanoribbon at nonzero temperature,although no spontaneous magnetization exists in a one-or two-dimensional isotropic Heisenberg model at any nonzer... Long-range magnetic order appears on a side decorated Heisenberg spin nanoribbon at nonzero temperature,although no spontaneous magnetization exists in a one-or two-dimensional isotropic Heisenberg model at any nonzero temperature according to the Mermin-Wagner theorem.By use of the spin Green's function method,we calculated the magnetizations of Heisenberg nanoribbons decorated by side spins with single-ion anisotropy and found that the system exhibits a nonzero transition temperature,whether the decorated edge spins of the system link together or separate from each other.When the width of the nanoribbon achieves infinite limit,the transition temperatures of the system tend to the same finite constant eventually whether one edge or both edges are decorated by side spins in the nanoribbon.The results reveal that the magnetism of a low-dimensional spin system is different from that of a threedimensional spin system.When the single-ion anisotropy of edge spins in a Heisenberg spin nanoribbon can be modulated by an electric field experimentally,various useful long-range magnetic orders of the system can be obtained.This work can provide a detailed theoretical basis for designing and fabricating next-generation low-dimensional magnetic random-access memory. 展开更多
关键词 NANORIBBON magnetic anisotropy long-range magnetic order Heisenberg model transition temperature
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Molecular dynamics simulations investigate the long-range effects on TrpR(tryptophan repressor protein)
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作者 FENG Xianli LIU Jia 《分子科学学报》 CAS 2024年第2期174-181,共8页
Molecular dynamics(MD)simulations and anisotropic thermal diffusion dynamics(ATD)simulations were performed on the wild TrpR and its 75 residue mutant(mTrpR)to investigate TrpR longrange effects.The ATD result shows t... Molecular dynamics(MD)simulations and anisotropic thermal diffusion dynamics(ATD)simulations were performed on the wild TrpR and its 75 residue mutant(mTrpR)to investigate TrpR longrange effects.The ATD result shows that the mTrpR has higher fluctuation than the wild TrpR,and its helix chainⅡF has particular disorder.It is obvious that the 75 residue of wild TrpR and mTrpR affects the protein dynamics flexibilities by the long-range effects.The ATD and MD both confirm that the differences in the size of side-chain and three-dimensional structures of two different 75 residues in the wild TrpR and mTrpR will spread to the entire protein by way of the long-range effects.Long-range effect affects the protein side chain interaction,conformational changes,flexibilities and secondary structures.Further,the ATD result also shows that each 75 residue of the symmetric homodimer has the same effect,and the two 75 residues have a positive correlation in long-range regulating processes.The residues 48,50,71,79 in chainⅠof wild TrpR and residues 45,72,80 in chainⅡof mTrpR play important roles in long-range interaction processes. 展开更多
关键词 MD ATD TrpR long-range effect
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Improved YOLOv7 Algorithm for Floating Waste Detection Based on GFPN and Long-Range Attention Mechanism
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作者 PENG Cheng HE Bing +1 位作者 XI Wenqiang LIN Guancheng 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2024年第4期338-348,共11页
Floating wastes in rivers have specific characteristics such as small scale,low pixel density and complex backgrounds.These characteristics make it prone to false and missed detection during image analysis,thus result... Floating wastes in rivers have specific characteristics such as small scale,low pixel density and complex backgrounds.These characteristics make it prone to false and missed detection during image analysis,thus resulting in a degradation of detection performance.In order to tackle these challenges,a floating waste detection algorithm based on YOLOv7 is proposed,which combines the improved GFPN(Generalized Feature Pyramid Network)and a long-range attention mechanism.Firstly,we import the improved GFPN to replace the Neck of YOLOv7,thus providing more effective information transmission that can scale into deeper networks.Secondly,the convolution-based and hardware-friendly long-range attention mechanism is introduced,allowing the algorithm to rapidly generate an attention map with a global receptive field.Finally,the algorithm adopts the WiseIoU optimization loss function to achieve adaptive gradient gain allocation and alleviate the negative impact of low-quality samples on the gradient.The simulation results reveal that the proposed algorithm has achieved a favorable average accuracy of 86.3%in real-time scene detection tasks.This marks a significant enhancement of approximately 6.3%compared with the baseline,indicating the algorithm's good performance in floating waste detection. 展开更多
关键词 floating waste detection YOLOv7 GFPN(Generalized Feature Pyramid Network) long-range attention
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Admission control with long-range dependence traffic input
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作者 饶云华 邹雪城 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第4期396-399,共4页
The admission control scheme is investigated for a FIFO self-similar queuing system with Quality of Service (QoS) performance guarantees. Since the self-similar queuing system performance analysis is often carried out... The admission control scheme is investigated for a FIFO self-similar queuing system with Quality of Service (QoS) performance guarantees. Since the self-similar queuing system performance analysis is often carried out under the condition of infinite buffer, it is difficult to deduce the upper boundary of buffer overflow probability. To overcome this shortcoming, a simple overflow condition is proposed, which defines a buffer overflow occurrence whenever the arrival rate exceeds the service rate. The analytic formula for the buffer overflow probability upper boundary is easily obtained under this condition. The required bandwidth upper boundary with long-range dependence input and determined overflow probability is then derived from this formula. Based on the above analytic formulas, the upper boundaries of the admission control regions for homogeneous and heterogeneous long-range dependence traffic sources are separately obtained. Finally, an effective admission control scheme for long-range dependence input is proposed. Simulation studies with real traffic have confirmed the validity of these results. 展开更多
关键词 long-range dependence queuing system overflow probability admission control
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The laser-intensity dependence of the photoassociation spectrum of the ultracold Cs_2(6S_(1/2) + 6P_(1/2))0_u^+ long-range molecular state
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作者 金丽 冯国胜 +4 位作者 武寄洲 马杰 汪丽蓉 肖连团 贾锁堂 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第8期732-737,共6页
The high-resolution photoassociation spectrum of the ultracold cesium molecular 0+ state below the 6S1/2 + 6PI/2 limit is presented in this paper. The saturation of the photoassociation scattering probability is obs... The high-resolution photoassociation spectrum of the ultracold cesium molecular 0+ state below the 6S1/2 + 6PI/2 limit is presented in this paper. The saturation of the photoassociation scattering probability is observed from the depen dence of the trap-loss probability on the photoassociation laser intensity. The corresponding resonant line width is also demonstrated to increase linearly with increasing photoassociation laser intensity. Our experimental data have good con sistency with the theoretical saturation model of Bohn and Julienne [Bohn J L and Julienne P S 1999 Phys. Rev. A 60 1]. 展开更多
关键词 photoassociation spectrum intensity dependence high resolution
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Effect of Brisk Walking on Self-Care Agency or Care Dependency among Colorectal Cancer Patients with Permanent Stoma
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作者 Zhen Zhang Anabella G.Javier 《Journal of Clinical and Nursing Research》 2024年第5期68-82,共15页
Objective:The purpose of this study was to determine the effectiveness of brisk walking as an intervention for self-care agency and care dependency in patients with permanent colorectal cancer stoma.Method:This study ... Objective:The purpose of this study was to determine the effectiveness of brisk walking as an intervention for self-care agency and care dependency in patients with permanent colorectal cancer stoma.Method:This study adopted a quasi-experimental research design,specifically a non-equivalent control group pre-test and post-test design.Utilizing the Exercise of Self-Care Agency Scale(ESCA)and Care Dependency Scale(CDS),a survey was administered to 64 patients from a hospital in Shandong Province.The statistical methods used for analyzing data included frequency,mean,standard deviation(SD),independent t-test,P-value calculation,and dependent t-test.Result:After two months of a brisk walking exercise program,participants in the experimental group had a higher level of self-care agency than before the experiment(P<0.05),and their level of care dependency was significantly reduced(P<0.05).Participants in the control group also showed higher levels of self-care agency(P<0.05)and lower levels of care dependency(P<0.05)after two months compared to their levels before the two months.Conclusion:The brisk walking program had a positive impact on patients’self-care agency and reduced their care dependency. 展开更多
关键词 Permanent stoma Colorectal cancer Brisk walking Self-care agency Care dependency
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Long-Range Dependencies Learning Based on Nonlocal 1D-Convolutional Neural Network for Rolling Bearing Fault Diagnosis
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作者 Huan Wang Zhiliang Liu Ting Ai 《Journal of Dynamics, Monitoring and Diagnostics》 2022年第3期148-159,共12页
In the field of data-driven bearing fault diagnosis,convolutional neural network(CNN)has been widely researched and applied due to its superior feature extraction and classification ability.However,the convolutional o... In the field of data-driven bearing fault diagnosis,convolutional neural network(CNN)has been widely researched and applied due to its superior feature extraction and classification ability.However,the convolutional operation could only process a local neighborhood at a time and thus lack the ability of capturing long-range dependencies.Therefore,building an efficient learning method for long-range dependencies is crucial to comprehend and express signal features considering that the vibration signals obtained in a real industrial environment always have strong instability,periodicity,and temporal correlation.This paper introduces nonlocal mean to the CNN and presents a 1D nonlocal block(1D-NLB)to extract long-range dependencies.The 1D-NLB computes the response at a position as a weighted average value of the features at all positions.Based on it,we propose a nonlocal 1D convolutional neural network(NL-1DCNN)aiming at rolling bearing fault diagnosis.Furthermore,the 1D-NLB could be simply plugged into most existing deep learning architecture to improve their fault diagnosis ability.Under multiple noise conditions,the 1D-NLB improves the performance of the CNN on the wheelset bearing data set of high-speed train and the Case Western Reserve University bearing data set.The experiment results show that the NL-1DCNN exhibits superior results compared with six state-of-the-art fault diagnosis methods. 展开更多
关键词 convolutional neural network fault diagnosis long-range dependencies learning rolling bearing
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Long-range Dependence Characteristics of Forest Biological Disasters in China against the Background of Climate Change
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作者 Benyang WANG Shiqing CHEN Shixiao YU 《Asian Agricultural Research》 2017年第4期85-91,共7页
Forest biological disasters(FBD) seriously impact energy flow and material cycling in forest ecosystems,while the underlying causes of FBD are complex. These disasters involve large areas and cause tremendous losses. ... Forest biological disasters(FBD) seriously impact energy flow and material cycling in forest ecosystems,while the underlying causes of FBD are complex. These disasters involve large areas and cause tremendous losses. As a result,the occurrence of FBDs in China( CFBD) threatens the country's ability to realize its strategic target of increasing both forested area(40 million ha) and forest volume(1.3 billion m^3) from 2005 to 2020. Collectively,China has officially named this effort to increase forest area and volume the "Two Increases" as national goals related to forestry. Based on Hurst index analysis from fractal theory,we analyzed the time series of the occurrence area and related data of FBDs from 1950 to 2007 to quantitatively determine the patterns of the macro occurrence of FBDs in China. Results indicates that,the time series of( CFBD) areas is fractal( self-affinity fractal dimension D = 1. 3548),the fluctuation of( CFBD) areas is positively correlated( auto-correlation coefficient C = 0. 2170),and the occurrence of the time series of( CFBD) is long-range dependent( Hurst index H =0. 6416),showing considerably strong trend of increases in FBDC area. Three different methods were further carried out on the original time series,and its two surrogate series generated by function surrogate in library t series,and function Surrogate Data in library in Wavelet software R,so as to analyze the reliability of Hurst indexes. The results showed that the Hurst indices calculated using different estimation methods were greater than 0. 5,ranging from 0. 64 to 0. 97,which indicated that the change of occurrence area data of FBDs was positively autocorrelated.The long-range dependence in forest biological disasters in China is obvious,and the spatial extent of FBDs tended to increase during this study period indicating this trend should be expected to persistent and worsen in the future. 展开更多
关键词 Forest pests and diseases Hurst index long-range correlation R/S analysis
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Complete f-Moment Convergence for Sung’s Type Weighted Sums of Negatively Superadditive Dependent Random Variables
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作者 HU Xueping WANG Liuliu +1 位作者 HU Ke XU Zhonghao 《应用概率统计》 北大核心 2025年第4期585-601,共17页
In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergen... In this paper,by utilizing the Marcinkiewicz-Zygmund inequality and Rosenthal-type inequality of negatively superadditive dependent(NSD)random arrays and truncated method,we investigate the complete f-moment convergence of NSD random variables.We establish and improve a general result on the complete f-moment convergence for Sung’s type randomly weighted sums of NSD random variables under some general assumptions.As an application,we show the complete consistency for the randomly weighted estimator in a nonparametric regression model based on NSD errors. 展开更多
关键词 Marcinkiewicz-Zygmund inequality Rosenthal-type inequality Sung’s type randomly weighted sums negatively superadditive dependent random variables complete f-moment convergence
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Exploring the multiplicity dependence of the flavor hierarchy for hadron production in high-energy pp collisions
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作者 Ao-Gui Zhang Xin-Ye Peng Liang Zheng 《Nuclear Science and Techniques》 2025年第8期126-137,共12页
In this study,we performed a systematic analysis of the multiplicity dependence of hadron production at mid-rapidity(|y|<0.5),ranging from the light to the charm sector in proton-proton(pp)collisions at√s=13 TeV.T... In this study,we performed a systematic analysis of the multiplicity dependence of hadron production at mid-rapidity(|y|<0.5),ranging from the light to the charm sector in proton-proton(pp)collisions at√s=13 TeV.This study used a multi-phase transport(AMPT)model coupled with PYTHIA8 initial conditions.We investigated the baryon-to-meson and the strange-to-non-strange meson ratios varying with the charged particle density.By tuning the coalescence parameters,the AMPT model provides a reasonable description of the experimental data for the inclusive production of both light and charm hadrons,comparable to the string fragmentation model calculations with color reconnection effects.Additionally,we analyzed the relative production of hadrons by examining the self-normalized particle ratios as a function of the charged hadron density.Our findings suggest that parton evolution effects and the coalescence hadronization process in the AMPT model result in a strong flavor hierarchy in the multiplicity dependence of the baryon-to-meson ratio.Furthermore,our investigation of the p_(T) differential double ratio of the baryon-to-meson fraction between high-and low-multiplicity events revealed distinct modifications to the flavor associated baryon-to-meson ratio p_(T) shape in high-multiplicity events when comparing the coalescence hadronization model to the color reconnection model.These observations highlight the importance of understanding the hadronization process in high-energy pp collisions through comprehensive multiplicity-dependent multi-flavor analysis. 展开更多
关键词 Heavy flavor Multiplicity dependence Small system AMPT
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Layer-dependent exciton dynamics in InSe/WS_(2)heterostructures
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作者 Siyao Li Yufan Wang +9 位作者 Zhiqiang Ming Yong Liu Lanyu Huang Siman Liu Jialong Li Yulin Chen Zhoujuan Xu Zeyu Liu Danliang Zhang Xiao Wang 《Chinese Physics B》 2025年第9期622-628,共7页
Understanding interlayer charge transfer is crucial for elucidating interface interactions in heterostructures.As the layer number can significantly influence the interface coupling and band alignment,the charge trans... Understanding interlayer charge transfer is crucial for elucidating interface interactions in heterostructures.As the layer number can significantly influence the interface coupling and band alignment,the charge transfer behaviors can be largely regulated.Here,we constructed two-dimensional(2D)heterostructures consisting of monolayer WS_(2)and few-layer InSe to investigate the impact of InSe thickness on exciton dynamics.We performed photoluminescence(PL)spectroscopy and lifetime measurements on pristine few-layer InSe and the heterostructures with different InSe thicknesses.For pristine InSe layers,we found a non-monotonic layer dependence on PL lifetime,which can be attributed to the interplay between the indirect-to-direct bandgap transition and surface recombination effects.For heterostructures,we demonstrated that the type I band alignment of the heterostructure facilitates electron and hole transfer from monolayer WS_(2)to InSe.As the InSe layer number increases,the reduction in conduction band minimum(CBM)enhances the driving force for charge transfer,thereby improving the transfer efficiency.Furthermore,we fabricated and characterized a WS_(2)/InSe optoelectronic device.By analyzing bias voltage dependent PL spectra,we further demonstrated that the trions in WS_(2)within the heterostructure are positively charged(X^(+)),and their emission intensity can be efficiently modulated by applying different biases.This study not only reveals the layer-dependent characteristics of band alignment and interlayer charge transfer in heterostructures but also provides valuable insights for the applications of 2D semiconductors in optoelectronic devices. 展开更多
关键词 EXCITON layer dependence charge transfer band alignment
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Acupuncture with different frequencies for tobacco dependence:a randomized controlled trial
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作者 CHEN Shumin LIU Zhenyu +4 位作者 JI Jia CHANG Jin LI Zhihua WANG Yingying YANG Jinsheng 《Journal of Traditional Chinese Medicine》 2025年第3期651-659,共9页
OBJECTIVE:To observe the effect of different acupuncture frequencies on the abstinence rate which could be used as a reference for optimizing acupuncture cessation programs.METHODS:From July 2018 to June 2022,a total ... OBJECTIVE:To observe the effect of different acupuncture frequencies on the abstinence rate which could be used as a reference for optimizing acupuncture cessation programs.METHODS:From July 2018 to June 2022,a total of 220 smokers were recruited based on inclusion criteria and randomly divided into the high-frequency acupuncture group(HF group,n=110):5 times a week from the 1st to the 4th week,from weeks 5 to 8,three times a week and the low-frequency acupuncture group(LF group,n=110):3 times a week from the 1st to the 4th week,from weeks 5 to 8,twice a week,then treated for 8 weeks and followup at 1 month in Beijing.RESULTS:In total,162 subjects completed the whole study with a drop-out rate of 20.45%.The expiratory CO point abstinence rate was HF group 53/110(48.18%)vs LF group 41/110(37.27%)in Week 8(P=0.102)and HF group 46/110(41.82%)vs LF group 45/110(40.91%)in Week 12(P=0.891)and the HF acupuncture and LF acupuncture were nearly equal in the 8-week abstinence rate.In addition,both HF and LF acupuncture significantly reduced Fagerstr?m test for nicotine dependence scale(FTND)scores(P<0.05),Minnesota nicotine withdrawal scale(MNWS)scores(P<0.05),and Brief Questionnaire of Smoking Urges scale(QSU-Brief)scores(P<0.05),but HF acupuncture showed some superiority over LF acupuncture in relieving patients'smoking cravings(P<0.05).CONCLUSIONS:The study initially showed that both high-frequency acupuncture and low-frequency acupuncture treatment were safe and effective on smoking cessation for 8 weeks,but high-frequency acupuncture was advantageous in reducing smoking cravings.More accurate acupuncture frequency needs to be validated through larger clinical studies to optimize acupuncture smoking cessation programs. 展开更多
关键词 ACUPUNCTURE acupuncture frequency tobacco dependence smoking cessation
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Surface element design of nanomaterials considering surface curvature dependence
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作者 Yongchao Zhang Lian Wang +2 位作者 Fangxin Wang Bin Li Xiaofan Gou 《Acta Mechanica Sinica》 2025年第1期42-53,共12页
Nanomaterials have garnered recognition for their notable surface effects and demonstration of superior mechanical properties.Previous studies on the surface effects of nanomaterials,employing the finite element metho... Nanomaterials have garnered recognition for their notable surface effects and demonstration of superior mechanical properties.Previous studies on the surface effects of nanomaterials,employing the finite element method,often relied on simplified twodimensional models due to theoretical complexities.Consequently,these simplified models inadequately represent the mechanical properties of nanomaterials and fail to capture the substantial impact of surface effects,particularly the curvature dependence of nanosurfaces.This study applies the principle of minimum energy and leverages the Steigmann-Ogden surface theory of nanomaterials to formulate a novel finite element surface element that comprehensively accounts for surface effects.We conducted an analysis of the stress distribution and deformation characteristics of four typical 2D and 3D nanomaterial models.The accuracy of the developed surface element and finite element calculation method was verified through comparison with established references.The resulting finite element model provides a robust and compelling scientific approach for accurately predicting the mechanical performance of nanomaterials. 展开更多
关键词 NANOMATERIALS Surface effect Surface element curvature dependence Finite element method
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