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An Extrapolated Parallel Subgradient Projection Algorithm with Centering Technique for the Convex Feasibility Problem 被引量:1
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作者 DANG Ya-zheng HAN Xue-feng GAO Yan 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第1期22-29,共8页
In this paper,we present an extrapolated parallel subgradient projection method with the centering technique for the convex feasibility problem,the algorithm improves the convergence by reason of using centering techn... In this paper,we present an extrapolated parallel subgradient projection method with the centering technique for the convex feasibility problem,the algorithm improves the convergence by reason of using centering techniques which reduce the oscillation of the corresponding sequence.To prove the convergence in a simply way,we transmit the parallel algorithm in the original space to a sequential one in a newly constructed product space.Thus,the convergence of the parallel algorithm is derived with the help of the sequential one under some suitable conditions.Numerical results show that the new algorithm has better convergence than the existing algorithms. 展开更多
关键词 convex feasibility problem SUBGRADIENT centering technique product space CONVERGENCE
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Could Sequential Residual Centering Resolve Low Sensitivity in Moderated Regression? Simulations and Cancer Symptom Clusters
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作者 Richard B. Francoeur 《Open Journal of Statistics》 2013年第6期24-44,共21页
Multicollinearity constitutes shared variation among predictors that inflates standard errors of regression coefficients. Several years ago, it was proven that the common practice of mean centering in moderated regres... Multicollinearity constitutes shared variation among predictors that inflates standard errors of regression coefficients. Several years ago, it was proven that the common practice of mean centering in moderated regression cannot alleviate multicollinearity among variables comprising an interaction, but merely masks it. Residual centering (orthogonalizing) is unacceptable because it biases parameters for predictors from which the interaction derives, thus precluding interpretation of moderator effects. I propose and validate residual centering in sequential re-estimations of a moderated regression—sequential residual centering (SRC)—by revealing unbiased multicollinearity conditioning across the interaction and its related terms. Across simulations, SRC reduces variance inflation factors (VIF) regardless of distribution shape or pattern of regression coefficients across predictors. For any predictor, the reduced VIF is used to derive a lower standard error of its regression coefficient. A cancer sample illustrates SRC, which allows unbiased interpretations of symptom clusters. SRC can be applied efficiently to alleviate multicollinearity after data collection and shows promise for advancing synergistic frontiers of research. 展开更多
关键词 Mean centering MULTICOLLINEARITY Moderated Regression Statistical Interaction Effect Modifier RESIDUAL centering Symptom Cluster SICKNESS Behavior MALAISE CANCER
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GRAPHICAL COMPUTING METHOD ON FOUR-BAR LINKAGE(1)——Inflexion Circle,Focal Axis,Ball's Point,Centering-point Curve and Circling-point Curve For Four ISPs,Coupler Curves Based on Ball's Points——
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作者 周晋康 《苏州大学学报(工科版)》 CAS 1992年第S2期27-34,共8页
By means of programs GTMPAC based- on generalized triangle method,analysis and synthesis of mechanism design in accordance with absolutely graphicalmethod( absolutely germetrical method) are developed.In this paper,we... By means of programs GTMPAC based- on generalized triangle method,analysis and synthesis of mechanism design in accordance with absolutely graphicalmethod( absolutely germetrical method) are developed.In this paper,we make aspecial study about centering- point curve and circling- point curve and couplercurves based on Ball’s points. 展开更多
关键词 Ball’s POINT centering - POINT CURVE and CIRCLING CURVE four ISPS Coupler curves based on BALLS Points
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Resilient performance of self-centering hybrid rocking walls with curved interface under pseudo-static loading
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作者 Su Xing Yan Shi +1 位作者 Sun Xianglei Wang Tao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期65-85,共21页
Frame and rocking wall(FRW)structures have excellent resilient performance during earthquakes.However,the concrete at interfacial corners of rocking walls(RWs)is easily crushed due to local extreme compression during ... Frame and rocking wall(FRW)structures have excellent resilient performance during earthquakes.However,the concrete at interfacial corners of rocking walls(RWs)is easily crushed due to local extreme compression during the rocking process.An innovative RW with a curved interface is proposed to prevent interfacial corners from producing local damage,enhancing its earthquake resilient performance(ERP).The precast wall panel with a curved interface is assembled into an integral self-centering hybrid rocking wall(SCRW)by two post-tensioned unbonded prestressed tendons.Moreover,two ordinary energy dissipation steel rebars and two shear reinforcements are arranged to increase the energy dissipation capacity and lateral resistance.Two SCRW specimens and one monolithic reinforced concrete(RC)shear wall(SW)were tested under pseudo-static loading to compare the ERPs of the proposed SCRW and the SW,focusing on studying the effect of the curved interface on the SCRW.The key resilient performance of rocking effects,failure modes,and hysteretic properties of the SCRW were explored.The results show that nonlinear deformations of the SCRW are concentrated along the interface between the SCRW and the foundation,avoiding damage within the SCRW.The restoring force provided by the prestressed tendons can effectively realize self-centering capacity with small residual deformation,and the resilient performance of the SCRW is better than that of monolithic SW.In addition,the curved interface of the SCRW makes the rocking center change and move inward,partially relieving the stress concentration and crush of concrete.The rocking range of the rocking center is about 41.4%of the width of the SCRW. 展开更多
关键词 self-centering hybrid rocking wall(SCRW) monolithic shear wall(SW) earthquake resilient performance(ERP) curved interface rocking center
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Local Curvature and Centering Effects in Nonlinear Regression Models
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作者 Michael Brimacombe 《Open Journal of Statistics》 2016年第1期76-84,共9页
The effects of centering response and explanatory variables as a way of simplifying fitted linear models in the presence of correlation are reviewed and extended to include nonlinear models, common in many biological ... The effects of centering response and explanatory variables as a way of simplifying fitted linear models in the presence of correlation are reviewed and extended to include nonlinear models, common in many biological and economic applications. In a nonlinear model, the use of a local approximation can modify the effect of centering. Even in the presence of uncorrelated explanatory variables, centering may affect linear approximations and related test statistics. An approach to assessing this effect in relation to intrinsic curvature is developed and applied. Mis-specification bias of linear versus nonlinear models also reflects this centering effect. 展开更多
关键词 Nonlinear Regression centering Data Model Mis-Specification BIAS CURVATURE
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怡化全面启动Call Centering服务系统
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《中国金融电脑》 2011年第8期94-94,共1页
本刊讯日前,怡化启动了自主研发的Call Center服务系统,致力让银行更好地了解设备运行状况,提供一站式怏捷的技术支持和售后服务,实现准确高效运营。该系统在YH—CRM客户关系管理信息平台的基础上,
关键词 服务系统 CENTER 设备运行状况 管理信息平台 自主研发 售后服务 技术支持 客户关系
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A self-centering and stiffness-controlled MEMS accelerometer
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作者 Yiming Jin Zhipeng Ma +3 位作者 Ziyi Ye Mingkang Li Xudong Zheng Zhonghe Jin 《Microsystems & Nanoengineering》 SCIE EI CSCD 2024年第1期27-40,共14页
This paper presents a high-performance MEMS accelerometer with a DC/AC electrostatic stiffness tuning capability based on double-sided parallel plates(DSPPs).DC and AC electrostatic tuning enable the adjustment of the... This paper presents a high-performance MEMS accelerometer with a DC/AC electrostatic stiffness tuning capability based on double-sided parallel plates(DSPPs).DC and AC electrostatic tuning enable the adjustment of the effective stiffness and the calibration of the geometric offset of the proof mass,respectively.A dynamical model of the proposed accelerometer was developed considering both DC/AC electrostatic tuning and the temperature effect.Based on the dynamical model,a self-centering closed loop is proposed for pulling the reference position of the forceto-rebalance(FTR)to the geometric center of DSPP.The self-centering accelerometer operates at the optimal reference position by eliminating the temperature drift of the readout circuit and nulling the net electrostatic tuning forces.The stiffness closed-loop is also incorporated to prevent the pull-in instability of the tuned low-stiffness accelerometer under a dramatic temperature variation.Real-time adjustments of the reference position and the DC tuning voltage are utilized to compensate for the residue temperature drift of the proposed accelerometer.As a result,a novel controlling approach composed of a self-centering closed loop,stiffness-closed loop,and temperature drift compensation is achieved for the accelerometer,realizing a temperature drift coefficient(TDC)of approximately 7μg/℃ and an Allan bias instability of less than 1μg. 展开更多
关键词 STIFFNESS ELECTROSTATIC centering
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High-entropy materials for photocatalysis
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作者 Rui Huang Heng Zhao Zhangxing Chen 《Nano Materials Science》 2026年第2期264-283,共20页
High-entropy materials(HEMs),characterized by their unique compositional diversity and configurational entropy,have emerged as promising candidates in the field of photocatalysis.These materials,typically composed of ... High-entropy materials(HEMs),characterized by their unique compositional diversity and configurational entropy,have emerged as promising candidates in the field of photocatalysis.These materials,typically composed of five or more principal elements,exhibit remarkable structural stability,enhanced electronic properties,and superior resistance to corrosion and oxidation.In the realm of photocatalysis,HEMs offer several advantages,including broad spectral absorption,efficient charge separation,and robust catalytic activity under various environmental conditions.This review summarizes recent advancements in the synthesis,characterization,and application of HEMs for photocatalytic processes,such as H_(2)evolution,CO_(2)conversion,organic pollutant degradation,and organic conversion.By exploring the intrinsic properties of HEMs and their synergistic effects,we aim to highlight their potential to revolutionize the design and development of next-generation photocatalysts.The integration of HEMs into photocatalytic systems not only paves the way for more efficient and sustainable energy conversion technologies but also opens new avenues for environmental remediation. 展开更多
关键词 High-entropy PHOTOCATALYSIS Heterogeneous catalysis Active centers Lattice distortion
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Towards energy-efficient data centers:A comprehensive review of passive and active cooling strategies
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作者 Senhong Cai Zhonghua Gou 《Energy and Built Environment》 2026年第1期206-226,共21页
With the rapid growth of cloud computing,the number of data centers(DCs)continuously increases,leading to a high-energy consumption dilemma.Cooling,apart from IT equipment,represents the largest energy consumption in ... With the rapid growth of cloud computing,the number of data centers(DCs)continuously increases,leading to a high-energy consumption dilemma.Cooling,apart from IT equipment,represents the largest energy consumption in DCs.Passive design(PD)and active design(AD)are two important approaches in architectural design to reduce energy consumption.However,for DC cooling,few studies have summarized AD,and there are almost no studies on PD.Based on existing international research(2005-2024),this paper summarizes the current state of cooling strategies for DCs.PD encompasses floors,ceilings,and layout and zoning of racks.Additionally,other passive strategies not yet studied in DCs are critically examined.AD includes air,liquid,free,and two-phase cooling.This paper systematically compares the performance of different AD technologies on various KPIs,including energy,economic,and environmental indicators.This paper also explores the application of different cooling design strategies through best-practice examples and presents advanced algorithms for energy management in operational DCs.This study reveals that free cooling is widely employed,with Artificial Neural Networks emerging as the most popular algorithm for managing cooling energy.Finally,this paper suggests four future directions for reducing cooling energy in DCs,with a focus on the development of passive strategies.This paper provides an overview and guide to DC energy-consumption issues,emphasizes the importance of implementing passive and active design strategies to reduce DC cooling energy consumption,and provides directions and references for future energy-efficient DC designs. 展开更多
关键词 Data center Passive design Active design Cooling load Energy efficiency
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Breaking ORR kinetic barriers in acid:Synergistic catalysis on PtPd dendrites featuring tailored asymmetry and high-index facets
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作者 Juan Luo Qing Li +6 位作者 Feng Liu Jingjing Huang Hao Cui Yuke Gu Meihuan Liu Pengfei Tan Jun Pan 《Journal of Energy Chemistry》 2026年第3期511-519,共9页
Overcoming kinetic limitations in the acidic oxygen reduction reaction(ORR)demands Pt-based catalysts with optimized surface adsorption.Herein,we engineer hierarchical PtPd dendrite nanocrystals(PtPd NDs)featuring pre... Overcoming kinetic limitations in the acidic oxygen reduction reaction(ORR)demands Pt-based catalysts with optimized surface adsorption.Herein,we engineer hierarchical PtPd dendrite nanocrystals(PtPd NDs)featuring precisely tailored asymmetric sites and high-index facets(HIFs)to overcome the kinetic limitations in acidic media.Controlled Pd incorporation disrupts symmetry of the single-oriented crystal plane,generating inhomogeneous strain and promoting HIFs exposure.This synergistic structural engineering optimizes the adsorption/desorption of oxygen-containing intermediates,significantly accelerating ORR kinetics.Consequently,PtPd NDs deliver exceptional mass activity(MA=1.37 A mg_(Pt)^(-1),11.42 times higher than Pt/C)and remarkable stability(83.9%MA retention after durability testing).In H_(2)-Air fuel cells,PtPd NDs also achieve higher peak power density versus Pt/C cathodes.In situ synchrotron radiation infrared spectroscopy and theoretical studies reveal that the synergistic effect between asymmetric sites and HIFs stimulates the strain field and causes a downward shift in the d-band center,thereby lowering the*OOH formation barrier and weakening intermediate adsorption,directly boosting the ORR performance.This work underscores the critical role of facet and site engineering in designing high-performance fuel cell electrocatalysts. 展开更多
关键词 Self-assembly strategy Asymmetric sites High-index facets d-band center Oxygen reduction reaction
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Mountain Science Data Center in IMHE
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《Journal of Mountain Science》 2026年第3期F0002-F0002,共1页
The Mountain Science Data Center(MSDC),founded in 2021 under the Institute of Mountain Hazards and Environment(IMHE),Chinese Academy of Sciences,manages the entire lifecycle of mountain science data.It integrates data... The Mountain Science Data Center(MSDC),founded in 2021 under the Institute of Mountain Hazards and Environment(IMHE),Chinese Academy of Sciences,manages the entire lifecycle of mountain science data.It integrates data from diverse sources,including debris flows,landslides,soils,ecology,geology,natural resources,basic geographic information,and socio-economic data.The center provides comprehensive services,including data collection,processing,analysis tools,modeling,and application support,offering reliable data backing for numerous research projects within the institute.Data management and services are accessible via the Mountain Science Data Center Portal(https://www.msdc.ac.cn/),ensuring long-term,stable,and trustworthy access to facilitate scientific research and institutional development. 展开更多
关键词 application supportoffering SOILS natural resources debris flows GEOLOGY debris flowslandslidessoilsecologygeologynatural mountain science data center LANDSLIDES
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Reconstruction of the"Reader Centered"Paradigm in the Teaching of High School English Literary Text Reading from the Perspective of Reception Aesthetics
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作者 Zhuohao Fei 《Research on Educational Theory》 2026年第1期1-6,共6页
This study focuses on reconstructing the"reader-centered"paradigm in the teaching of high school English literary text reading,supported by Reception Aesthetics as its theoretical foundation.High school Engl... This study focuses on reconstructing the"reader-centered"paradigm in the teaching of high school English literary text reading,supported by Reception Aesthetics as its theoretical foundation.High school English literary text reading plays a significant role in cultivating students'language proficiency,cultural awareness,and aesthetic literacy.However,the current teaching practice in this area remains dominated by the traditional"teacher-centered"approach,which restricts students'active participation and the realization of the pluralistic value of literary texts.By integrating core concepts of Reception Aesthetics-such as"horizon of expectations,""structure of appeal,"and"interpretive community"-this research addresses the gap in existing studies,which have largely focused on the application of Reception Aesthetics in Chinese language teaching or college English instruction.Using literature research and classroom practice analysis,the study reconstructs the"reader-centered"paradigm across three dimensions:teaching objectives,teaching process,and evaluation methods.It also identifies practical challenges,including uneven student participation,time constraints,and difficulties in the teacher's role adaptation,and proposes corresponding optimization strategies.Practical results demonstrate that this paradigm effectively enhances students'reading engagement,text interpretation skills,and critical thinking.Future research may further expand text types and integrate information technology to continuously improve teaching effectiveness. 展开更多
关键词 Reception Aesthetics Reader Centered English teaching
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CULTURE
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《China Today》 2026年第2期14-15,共2页
NCPA Drama Commission:Suspect Sherlock Holmes Date:February 5-14,2026 Venue:National Center for the Performing Arts As the first suspense drama commission to be produced by the NCPA,Suspect Holmes is derived from a le... NCPA Drama Commission:Suspect Sherlock Holmes Date:February 5-14,2026 Venue:National Center for the Performing Arts As the first suspense drama commission to be produced by the NCPA,Suspect Holmes is derived from a legendary detective story,featuring iconic characters including Sherlock Holmes,John Watson,Professor Moriarty,Mycroft Holmes,policeman Lestrade,and Mrs.Hudson. 展开更多
关键词 FEBRUARY Suspect Sherlock Holmes National Center Performing Arts sherlock holmes Drama Commission John Watson suspense drama
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Modulation of Trichromatic Emission Centers in Organic-Inorganic Hybrids for Optoelectronic Applications
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作者 Weidong Cai Chongyuan Li +3 位作者 Qiang Guo Fuxiang Ji Muyi Zhang Yiqiang Zhan 《Nano-Micro Letters》 2026年第4期831-845,共15页
Organic-inorganic metal halides(OIMHs)have emerged as highly promising novel multifunctional optoelectronic materials,owing to their easily adjustable properties from a variety of combinations of different components.... Organic-inorganic metal halides(OIMHs)have emerged as highly promising novel multifunctional optoelectronic materials,owing to their easily adjustable properties from a variety of combinations of different components.But it is still difficult and rare to realize highly tunable multicolor luminescence within the same material.In this work,we successfully incorporated three adjustable emission centers in OIMHs to synthesize a novel OIMH(NEA)_(2)MnBr_(4),with each emission center capable of emitting one of the primary colors—red,green,and blue.The green and red emissions originate from the tetrahedron and octahedron structures in the Mn-based frame,while the blue can be attributed to the contribution of organic components.Additionally,to achieve comparable emission intensity among the three primary colors,we enhanced the blue emission performance by optimizing the ratio of organic structure components and incorporating chirality in the OIMHs.The resulting high-quality films can be obtained by spin-coating method with a photoluminescence quantum yields of up to 96%.More interestingly,by the dual manipulation of excitation wavelength and temperature,the sample can be emitted at least seven distinct colors including a standard white luminescence at(0.33,0.33),opening up promising prospects for multicolor luminescence applications such as high-end anti-counterfeiting technology,light-emitting diodes,X-ray imaging,latent fingerprints,humidity detection,and so on.Therefore,based on application scenarios and requirements,our research on this highly tunable luminescent OIMH material lays a solid foundation for further development of various functional properties of related materials. 展开更多
关键词 Trichromatic emission centers Multicolor tuning Chiral organic and inorganic halides X-ray imaging Latent fingerprints
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Thermoeconomic assessment of the air-cooled tropical data center through energy-saving strategies
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作者 Jing Zhou Baris Burak Kanbur +2 位作者 Duc Van Le Rui Tan Fei Duan 《Energy and Built Environment》 2026年第1期115-127,共13页
Rapid developments in the electronic information industry drive the increased energy usage and carbon emission of data center buildings,prompting the focus on the energy efficiency and environmental sustainability.Exp... Rapid developments in the electronic information industry drive the increased energy usage and carbon emission of data center buildings,prompting the focus on the energy efficiency and environmental sustainability.Expanded operation envelopes of tropical data centers is assessed to analyze the potential for the building energy savings and carbon emission reduction through collaborative analysis of operation modes(OMs),supply air temperature(SAT),and outdoor air temperature(OAT).The OMs of compression vary with the setpoints of SAT,in which the average exergy efficiency of compressors at alternate operation mode is 6.8%and 8.0%lower than that of double and single compression operations.As SAT rises from 20℃to 32℃,the system exergoeconomic factor increases from 5.4%to 8.0%,and the average carbon cost decreases by 36.5%.Additionally,with just an 8.5%increase in exergy cost(i.e.,Case 8)at OAT rising from 30 to 34℃,the high SAT and low refrigerant charges provide considerable exergy cost advantages versus resisting the OAT fluctuations.Dynamic operation strategies are also proposed and compared to cope with the impacts of tropical environments.Compared to the 26℃SAT baseline,the average energy savings are 9.1-14.7%,indicating the ability to fully utilize outdoor and indoor conditions. 展开更多
关键词 Tropical data center cooling Energy-saving strategies Thermoeconomic assessments Supply air temperature assessment Outdoor air temperature effect
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Hainan’s“Clean Energy Island”Vision
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作者 WEI HONGCHEN 《China Today》 2026年第3期40-43,共4页
Siemens and Yangpu Economic Development Zone in Hainan have forged a close partnership in a journey towards green energy transition.SIEMENS Energy,one of the world’s leading energy technology companies,became the fir... Siemens and Yangpu Economic Development Zone in Hainan have forged a close partnership in a journey towards green energy transition.SIEMENS Energy,one of the world’s leading energy technology companies,became the first foreign-funded manufacturer to establish a branch and began construction of a gas turbine assembly base and service center in Hainan on December 18,2025. 展开更多
关键词 gas turbine establish branch clean energy island Siemens Energy service center Yangpu Economic Development Zone green energy green energy transition
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A BLUEPRINT FOR PEOPLE-CENTERED DEVELOPMENT
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作者 Carlos Martinez 《China Report ASEAN》 2026年第1期64-64,共1页
The 20th Communist Party of China(CPC)Central Committee held its fourth plenary session in Beijing on October 20-23.The plenary session's central task was to deliberate on the framework of the country's next n... The 20th Communist Party of China(CPC)Central Committee held its fourth plenary session in Beijing on October 20-23.The plenary session's central task was to deliberate on the framework of the country's next national development roadmap:the 15th Five-Year Plan(2026-2030).Every five-year plan is important but this one arrives at a truly pivotal moment in terms of China's development trajectory and the global environment. 展开更多
关键词 plenary sessions people centered development national development roadmap deliberate framework th CPC Central Committee global environment th five year plan
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基于改进SimCLR框架的航空发动机多类型损伤检测方法研究
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作者 梁桦 尹登峰 +1 位作者 艾兴 刘妍 《长江信息通信》 2025年第10期28-30,共3页
文章提出一种基于改进SimCLR框架的航空发动机多类型损伤检测方法,融合多源时序信号,结合时间与频率域的联合增强策略,模拟复杂工况下的损伤变化特征。通过引入Transformer编码器增强跨通道长依赖建模能力,并结合类别中心引导机制与Cent... 文章提出一种基于改进SimCLR框架的航空发动机多类型损伤检测方法,融合多源时序信号,结合时间与频率域的联合增强策略,模拟复杂工况下的损伤变化特征。通过引入Transformer编码器增强跨通道长依赖建模能力,并结合类别中心引导机制与Center Loss优化对比空间特征分布。实验在典型航空发动机故障数据集上验证了该方法在特征区分性与分类性能上的优势,准确率达91%,显著优于传统方法,为无监督多类损伤检测提供了有效途径。 展开更多
关键词 SimCLR TRANSFORMER 对比学习 Center Loss 无监督故障诊断
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High-entropy alloy nanocrystals boosting photocatalytic hydrogen evolution coupled with selective oxidation of cinnamyl alcohol 被引量:2
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作者 Xianglin Xiang Bei Cheng +2 位作者 Bicheng Zhu Chuanjia Jiang Guijie Liang 《Chinese Journal of Catalysis》 2025年第1期326-335,共10页
Photocatalysis provides a promising solution to the worldwide shortages of energy and industrially important raw materials by utilizing sunlight for coupled hydrogen(H_(2))production with controllable organic transfor... Photocatalysis provides a promising solution to the worldwide shortages of energy and industrially important raw materials by utilizing sunlight for coupled hydrogen(H_(2))production with controllable organic transformation.Herein,we demonstrate that PtFeNiCoCu high-entropy alloy(HEA)nanocrystals can act as efficient cocatalysts for H_(2)evolution coupled with selective oxidation of cinnamyl alcohol to cinnamaldehyde by cubic cadmium sulfide(CdS)quantum dots(QDs)with uniform sizes of 4.0±0.5 nm.HEA nanocrystals were prepared via a simple solvothermal approach,and were successfully integrated with CdS QDs by an electrostatic self-assembly method to construct HEA/CdS composites.The optimized HEA/CdS sample presented an enhanced photocatalytic H_(2)production rate of 7.15 mmol g^(-1)h^(-1),which was 13 times that of pure CdS QDs.Moreover,a cinnamyl alcohol conversion of 96.2%with cinnamaldehyde selectivity of 99.5%was achieved after photoreaction for 3 h.The integration of HEA with CdS QDs extended the optical absorption edge from 475 to 484 nm.From d-band center analysis,Pt atoms in the HEA are the active sites for H_(2)evolution,exhibiting higher catalytic activity than pure Pt.Meanwhile,the band structure of the CdS QDs enables the oxidative transformation of cinnamyl alcohol to cinnamaldehyde with high selectivity.Moreover,femtosecond transient absorption spectroscopy shows that HEA can significantly promote the separation of photogenerated carriers in CdS,which is vital for achieving enhanced photocatalytic activity.This work inspires atomic-level design of photocatalytic materials for coordinated production of green energy carriers and value-added products. 展开更多
关键词 Artificial photosynthesis d-Band center Photocatalytic hydrogen evolution Quantum dots Value-added organic synthesis
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无人机倾斜摄影测量技术在土方测量中的应用研究 被引量:2
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作者 朱言灯 蓝天 吕树辰 《建筑科技》 2025年第10期68-71,共4页
无人机技术的发展,为工程土方测量开辟了新思路。针对传统测量方法的弊端,以上海交通大学医学院浦东校区工程(标段二)为背景,阐述采用无人机倾斜摄影测量技术开展土方测量的应用全过程。利用无人机倾斜摄影测量技术对项目土石方阶段场... 无人机技术的发展,为工程土方测量开辟了新思路。针对传统测量方法的弊端,以上海交通大学医学院浦东校区工程(标段二)为背景,阐述采用无人机倾斜摄影测量技术开展土方测量的应用全过程。利用无人机倾斜摄影测量技术对项目土石方阶段场地数据进行采集,通过Context Capture Center Master软件进行数据处理,生成项目的场地数字表面模型(DSM);对土方量进行测算并与实际开挖量进行对比,通过差值比例验证土方量的测算精度,证实采用无人机倾斜摄影实景三维建模进行土方测量的可行性。 展开更多
关键词 无人机 倾斜摄影 土方测量 Pix4D软件 Context Capture Center Master软件
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