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Signifying quantum uncertainty relations by optimal observable sets and the tightest uncertainty constants

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 43-50页

作者： Xiao-Bin liang Bo Li Shao-Ming fei School of Mathematics and Computer Science Shangrao Normal UniversityShangrao 334001China Quantum Information Research Center Shangrao Normal UniversityShangrao 334001China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

Quantum uncertainty relations constrain the precision of measurements across multiple non-commuting quantum mechanical ***,we introduce the concept of optimal observable sets and define the tightest uncertainty constants to accurately describe these measurement *** any quantum state,we establish optimal sets of three observables for both product and summation forms of uncertainty relations,and analytically derive the corresponding tightest uncertainty *** demonstrate that the optimality of these sets remains consistent regardless of the uncertainty relation ***,the existence of the tightest constants excludes the validity of standard real quantum mechanics,underscoring the essential role of complex numbers in this ***,our findings resolve the conjecture posed in[***.118,180402(2017)],offering novel insights and potential applications in understanding preparation uncertainties.

关键词： uncertainty relation the tightest uncertainty constants optimal observable sets

Insights into the provenance implication of leaf wax n-alkanes along the lower Yellow River

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Science China Earth Sciences 2024年第6期67卷 2001-2018页

作者： liang ZHANG Jinzhao LIU Chong JIANG fei ZHANG Zhisheng AN School of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710054China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China National Observation and Research Station of Earth Critical Zone on the Loess Plateau of Shaanxi Xi’an 710061China

Serving as one of the largest rivers in terms of both sediment and organic carbon transport fluxes in the world,the Yellow River plays a crucial role in regional biogeochemical process as well as in the global carbon ***,although a large number of studies have been carried out on the flux,composition,source and seasonal variation of total particulate organic carbon in the Yellow River so far,studies on molecular biomarkers at different spatial and temporal scales are still *** this study,we focus on the molecular and hydrogen isotopic properties of leaf wax n-alkanes among different types of samples which obtained from different seasons(flood ***-flood)along the lower Yellow *** molecular distribution of n-alkanes show that the riparian topsoils are subject to inputs from the overlying vegetation,while the suspended sediments from the flood season are characterized by the mixing of soil materials which originate from various stratigraphy with different ages on the Chinese Loess *** to the contrasting hydrodynamic conditions,the n-alkanes in suspended sediments also show distinct molecular composition between flood and non-flood ***,considering the effect of climatic factors,the proportion of monocots in flood-season suspended sediments is calculated from a semi-quantitative perspective using δ^(2)H_(wax).Our findings may bring to light new considerations for the interpretation of leaf wax proxies in studies of organic matter sources of Yellow River.

关键词： Molecular distribution Hydrogen isotopic composition Leaf wax n-alkanes Suspended sediments Lower Yellow River

IHVFL: a privacy-enhanced intention-hiding vertical federated learning framework for medical data

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Cybersecurity 2024年第2期7卷 96-112页

作者： fei Tang Shikai liang Guowei Ling Jinyong Shan College of Computer Science and Technology Chongqing University of Posts and TelecommunicationsNo.2Chongwen RoadNan'an DistrictChongqing 400065China School of Cyber Security and Information Law Chongqing University of Posts and TelecommunicationsChongqing 400065China sudo Technology Co. LTD.Beijing 100083China

Vertical Federated Learning(VFL)has many applications in the field of smart healthcare with excellent ***,current VFL systems usually primarily focus on the privacy protection during model training,while the preparation of training data receives little *** real-world applications,like smart healthcare,the process of the training data preparation may involve some participant's intention which could be privacy information for this *** protect the privacy of the model training intention,we describe the idea of Intention-Hiding Vertical Feder-ated Learning(IHVFL)and illustrate a framework to achieve this privacy-preserving ***,we construct two secure screening protocols to enhance the privacy protection in feature ***,we implement the work of sample alignment bases on a novel private set intersection ***,we use the logistic regression algorithm to demonstrate the process of *** show that our model can perform better efficiency(less than 5min)and accuracy(97%)on Breast Cancer medical dataset while maintaining the intention-hiding goal.

关键词： Medical data Vertical federated learning Privacy-presserving Intention-hiding Logistic regression

Three-dimensional numerical manifold method for heat conduction problems with a simplex integral on the boundary

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Science China(Technological Sciences) 2024年第4期67卷 1007-1022页

作者： TONG DeFu YI XiongWei TAN fei JIAO YuYong liang JiaWei Faculty of Engineering China University of GeoscienceWuhan 430074China Department of Civil Engineering Monash UniversityMelbourne VIC 3800Australia Badong National Observation and Research Station of Geohazards China University of GeoscienceWuhan 430074China

The three-dimensional numerical manifold method(3D-NMM),which is based on the derivation of Galerkin's variation,is a powerful calculation tool that uses two cover *** 3D-NMM can be used to handle continue-discontinue problems and extend to THM *** this study,we extended the 3D-NMM to simulate both steady-state and transient heat conduction *** modelling was carried out using the raster methods(RSM).For the system equation,a variational method was employed to drive the discrete equations,and the crucial boundary conditions were solved using the penalty *** solve the boundary integral problem,the face integral of scalar fields and two-dimensional simplex integration were used to accurately describe the integral on polygonal *** numerical examples were used to verify the results of 3D steady-state and transient heat-conduction *** numerical results indicated that the 3D-NMM is effective for handling 3D both steadystate and transient heat conduction problems with high solution accuracy.

关键词： three-dimensional numerical manifold method transient analysis heat conduction problem Galerkin variation simplex integration

Hybrid effect on mechanical properties and high-temperature performance of copper matrix composite reinforced with micro-nano dual-scale particles

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Journal of Materials Science & Technology 2024年第5期172卷 94-103页

作者： Xingde Zhang Yihui Jiang fei Cao Tian Yang Fan Gao Shuhua liang School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China Engineering Research Center of Conducting Materials and Composite Technology Ministry of EducationXi’an University of TechnologyXi’an 710048China Shaanxi Province Key Laboratory of Electrical Materials and Infiltration Technology Xi’an University of TechnologyXi’an 710048China

A dual-scale hybrid HfB_(2)/Cu-Hf composite with HfB_(2) microparticles and Cu_(5) Hf nanoprecipitates was designed and *** contribution of the hybrid effect to the mechanical properties and high-temperature performances was studied from macro and micro perspectives,*** hybrid of dual-scale particles can make the strain distribution of the composite at the early deformation stage more uniform and delay the strain concentration caused by the HfB_(2) *** dislocation pinning of HfB_(2) particles and the coherent strengthening of Cu_(5) Hf nanoprecipitates simultaneously play a strengthening role,but the strength of the hybrid composite is not a simple superposition of two strengthening *** addition,both Cu_(5) Hf nanoprecipitates and HfB_(2) microparticles contribute to the high-temperature performance of the composite,the growth and phase transition of nanoprecipitates at high temperature will reduce their contribution to strength,while the stable HfB_(2) particles can inhibit the coarsening of matrix grains and maintain the high-density geometrically necessary dislocations(GNDs)in the matrix,which ensures more excellent high-temperature resistance of the hybrid *** a result,the hy-brid structure can simultaneously possess the advantages of multiple reinforcements and make up for the shortcomings of each ***,a copper matrix composite with high strength,high conductivity,and excellent high-temperature performance is displayed.

关键词： Copper matrix composite HfB 2 particles Hybrid effect High strength and high conductivity High-temperature performance

Critical roles of control engineering in the development of intelligent and connected vehicles

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Journal of Intelligent and Connected Vehicles

Journal of Intelligent and Connected Vehicles 2024年第2期7卷 79-85页

作者： Yang fei Peng Shi Yang Liu liang Wang School of Vehicle and Mobility Tsinghua UniversityBeijing 100084China School of Electrical and Mechanical Engineering The University of AdelaideAdelaide SA 5005Australia Research and Innovation Centre Obuda UniversityBudapest 1034Hungary Department of Architecture and Civil Engineering Chalmers University of TechnologyGothenburg SE-41296Sweden

1 Introduction In recent years,advancements in onboard computing hardware and wireless communication technology have remarkably stimulated the development of intelligent and connected vehicles(ICVs).Specifically,some researchers have investigated the issue of employing various advanced control techniques to optimize the performance of autonomous vehicles in practice(Sun et al.,2023;Zhang et al.,2023a,2023b).Therefore,this article aims to discuss why and how control engineering plays an essential role in the development of ICVs.

关键词： connected hardware intelligent

Highly selective and eco-friendly dihydroisoquinoline synthesis via Cu/Co synergistic catalysis in Cu NPs@MOFs catalyst under mild conditions

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Science China Chemistry 2024年第5期67卷 1561-1568页

作者： Peng-fei Guo Ze-Long liang Yue-E Jiao Hang Xu Bin Zhao Key Laboratory of Advanced Energy Material Chemistry Renewable Energy Conversion and Storage CenterDepartment of ChemistryNankai UniversityTianjin 300071China

3,4-Dihydroisoquinoline(DHIQ)is an important precursor used in the production of drugs for treating cancer,HIV,Alzheimer's disease,*** studies on DHIQ synthesis show low catalytic selectivity due to the susceptible over-oxidation feedstock of1,2,3,4-tetrahydroisoquinoline(THIQ),which often requires alkali ***,it is desirable yet challenging to explore a highly selective and efficient oxydehydrogenation capacity for DHIQ synthesis under eco-friendly reaction ***,a novel framework 1 was synthesized,exhibiting 1D channels with the size of 4.6 A×9.6 A and high solvent/p H/thermal stability.A stable framework allows it to encapsulate Cu nanoparticles(NPs)to form Cu NPs@1-x(x=1,2,3,and 4)with varying loading amounts of Cu NPs at 2.0 wt%,3.0 wt%,4.0 wt%,and 6.0 wt%,*** NPs@1-3 could selectively catalyze the reaction from THIQ to DHIQ with a high selectivity of 98%and a recorded turnover frequency(TOF)of 22.1 h-1under eco-friendly mild *** corresponding catalytic activity can maintain at least five recyclings and can be further applied to gram-scale ***,the efficient preparation of DHIQ catalyzed by Cu NPs@1-3 could be realized even under air ***,the anticancer molecule precursor synthesis of 6,7-dimethoxy-3,4-dihydroisoquinoline was also selectively catalyzed by Cu NPs@*** investigations revealed that high catalytic performance can be attributed to the stable framework and the synergistic catalytic effect of the loaded Cu NPs and Co metal *** importantly,this work represents the first example of MOF catalysts for selectively thermo-catalytic DHIQ synthesis and demonstrates a simple approach to obtain efficient catalysts for selective oxydehydrogenation in the production of unsaturated compounds.

关键词： metal-organic frameworks Cu NPs@MOFs 3 4-dihydroisoquinoline selective oxydehydrogenation synergistic catalysis

Could the EU carbon border adjustment mechanism promote climate mitigation?An economy-wide analysis

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Advances in Climate Change Research 2024年第3期15卷 557-571页

作者： Kun ZHANG Yun-fei YAO Xiang-Yan QIAN Yu-fei ZHANG Qiao-Mei liang Yi-Ming WEI College of Economics and Management Beijing University of TechnologyBeijing 100124China Center for Energy and Environmental Policy Research Beijing Institute of TechnologyBeijing 100081China School of Management and Economics Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Energy Economics and Environmental Management Beijing 100081China Sinopec Research Institute of Petroleum Engineering SinopecBeijing 100101China College of Economics and Management Nanjing Agricultural UniversityNanjing 210095China

Due to concerns about carbon leakage and sectoral competitiveness,the European Union(EU)proposed implementing the carbon border adjustment mechanism(CBAM).The effectiveness and potential negative consequences of CBAM have aroused extensive *** the perspective of the economy-wide analysis,this study uses a global computable general equilibrium model to explore the rationality of CBAM from the aspects of socioeconomic impact and the effects of promoting climate ***,the potential alternative mechanism of CBAM is *** results show that CBAM can reduce the EU's gross domestic product(GDP)loss;however,the GDP loss in all other regions ***,CBAM raises household welfare losses in most regions,including the ***,although CBAM can reduce the marginal abatement cost in eight regions,it comes at the cost of greater economic ***,the economic and household welfare cost of raising emissions reduction targets in regions like the USA and Japan is substantially higher than the impact of passively accepting the CBAM;therefore,CBAM's ability to drive ambitious emission reduction initiatives may be ***,for the potential alternative mechanism,from the perspective of reducing economic cost and household welfare losses,the EU could implement domestic tax cuts in the short-term and promote global unified carbon pricing in the long-term.

关键词： Border adjustment mechanism Computable general equilibrium model Carbon price Climate policy Global carbon pricing

Mid-infrared computational temporal ghost imaging

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Light(Science & Applications) 2024年第6期13卷 1088-1097页

作者： Han Wu Bo Hu Lu Chen fei Peng Zinan Wang Goery Genty Houkun liang College of Electronics and Information Engineering Sichuan UniversityChengduSichuan610064China College of Electrical Engineering Sichuan UniversityChengduSichuan610064China Key Lab of Optical Fiber Sensing&Communications University of Electronic Science&Technology of ChinaChengduSichuan611731China Laboratory of Photonics Tampere UniversityFI-33014TampereFinland

Ghost imaging in the time domain allows for reconstructing fast temporal objects using a slow *** technique involves correlating random or pre-programmed probing temporal intensity patterns with the integrated signal measured after modulation by the temporal ***,the implementation of temporal ghost imaging necessitates ultrafast detectors or modulators for measuring or pre-programming the probing intensity patterns,which are not available in all spectral regions especially in the mid-infrared ***,we demonstrate a frequency downconversion temporal ghost imaging scheme that enables to extend the operation regime to arbitrary wavelengths regions where fast modulators and detectors are not *** approach modulates a signal with temporal intensity patterns in the near-infrared and transfers the patterns to an idler via difference-frequency generation in a nonlinear crystal at a wavelength where the temporal object can be *** a proof-of-concept,we demonstrate computational temporal ghost imaging in the mid-infrared with operating wavelength that can be tuned from 3.2 to 4.3μ*** scheme is flexible and can be extended to other *** results introduce new possibilities for scan-free pump-probe imaging and the study of ultrafast dynamics in spectral regions where ultrafast modulation or detection is challenging such as the mid-infrared and THz regions.

关键词： ghost Ghost scheme