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Journal of Rare Earths 2024年第2期42卷 256-262,I0001页

作者： Tianqi Cao Yuxin Liu Qi Jia Xiaolu Wang Shouqiang Zhang Jing Zhou Department of Chemistry Capital Normal UniversityBeijing100048China

Chemotherapy,the use of antitumor drugs to kill cancer cells,is currently one of the most effective treatments for ***,serious toxic side effects caused by long-term drug accumulation can cause significant damage to the body,which limits the clinical application of antitumor *** this study,a novel RENPs@DOX-Fe nanoprobe(NP) was constructed by coating the surface of rare earth nanomaterials(NaLuF_(4):Yb,Er) with a complex formed by doxorubicin(DOX) and iron ion(Ⅲ).Due to the low toxicity of anthracycline-metal complexes,the damage to normal cells is *** unique acidic microenvironment in tumor cells facilitates the decomposition and gradual release of DOX from the DOX-Fe *** addition,the DOX-Fe complex can convert near-infrared(NIR) light into heat energy,which promotes the decomposition of the complex,further enhancing the release of DOX in the tumor *** change of ratio fluorescence of rare earth nanomaterials at 660 and 1550 nm after DOX release enables visual monitoring of drug release,which can potentially improve the chemotherapeutic *** vitro experiments established that RENPs@DOX-Fe NPs with NIR illumination had good therapeutic efficacy in *** work provides new insights into designing tumor microenvironment-responsive nanoprobes for chemotherapy with minimal side effects.

关键词： Rare earth nanoprobes Fluorescence Ratiometric imaging DOX Chemotherapy

Identification of rural courtyards’utilization status using deep learning and machine learning methods on unmanned aerial vehicle images in north China

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Building Simulation 2024年第5期17卷 799-818页

作者： Maojun Wang Wenyu Xu Guangzhong Cao Tao Liu College of Resource Environment and Tourism Capital Normal UniversityBeijing 100048China College of Urban and Environmental Sciences Peking UniversityBeijing 100871China

The issue of unoccupied or abandoned homesteads(courtyards)in China emerges given the increasing aging population,rapid urbanization and massive rural-urban *** the aspect of rural vitalization,land-use planning,and policy making,determining the number of unoccupied courtyards is *** and questionnaire-based surveys were currently the main approaches,but these traditional methods were often expensive and laborious.A new workflow is explored using deep learning and machine learning algorithms on unmanned aerial vehicle(UAV)***,features of the built environment were extracted using deep learning to evaluate the courtyard management,including extracting complete or collapsed farmhouses by Alexnet,detecting solar water heaters by YOLOv5s,calculating green looking ratio(GLR)by *** precisions exceeded 98%.Then,seven machine learning algorithms(Adaboost,binomial logistic regression,neural network,random forest,support vector machine,decision trees,and XGBoost algorithms)were applied to identify the rural courtyards’utilization *** Adaboost algorithm showed the best performance with the comprehensive consideration of most metrics(Accuracy:0.933,Precision:0.932,Recall:0.984,F1-score:0.957).Results showed that identifying the courtyards’utilization statuses based on the courtyard built environment is *** is transferable and cost-effective for large-scale village surveys,and may contribute to the intensive and sustainable approach to rural land use.

关键词： unoccupied homesteads courtyard built environment inner courtyard management GLR solar water heaters machine learning algorithms

Factor Structure and Longitudinal Invariance of the CES-D across Diverse Residential Backgrounds in Chinese Adolescents

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International Journal of Mental Health Promotion 2024年第4期26卷 261-269页

作者： Yanjing Cao Chenchen Xu Qi Li Shan Lu Jing Xiao beijing Key Laboratory of Learning and Cognition and Department of Psychology Capital Normal UniversityBeijing100048China Center for Child Development Capital Normal UniversityBeijing100048China

Background:Valid and reliable measures of depressive symptoms are crucial for understanding risk factors,outcomes,and interventions across rural and urban *** this need,the longitudinal invariance of these measures over time remains *** research explores the structural components of the Center for Epidemiological Studies Depression Scale(CES-D)and examines its consistency across various living environments and temporal stability in a cohort of Chinese ***:In the initial phase,1,042 adolescents furnished demographic details and undertook the CES-D *** a three-month interval,967 of these participants repeated the CES-D *** study employed Confirmatory factor analysis(CFA)to scrutinize the scale’s structural *** investigated factorial invariance by conducting a twopronged CFA:one comparing urban *** backgrounds,and another contrasting the results from the initial assessment with those from the ***:The CES-D demonstrated adequate reliability in both rural and urban high school student *** preliminary four-factor model applied to the CES-D demonstrated a good fit with the collected *** tests,including multigroup analyses comparing rural and urban samples and longitudinal assessments,confirmed the scale’s ***:The results suggest that the CES-D serves as a reliable instrument for evaluating depressive symptoms among Chinese *** applicability is consistent across different living environments and remains stable over time.

关键词： Depression factor structure measurement invariance Chinese adolescent longitudinal invariance

A New High-Precision and Lightweight Detection Model for Illegal Construction Objects Based on Deep Learning

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Tsinghua Science and Technology 2024年第4期29卷 1002-1022页

作者： Wenjin Liu Lijuan Zhou Shudong Zhang Ning Luo Min Xu School of Cyberspace Security(School of Cryptology) Hainan UniversityHaikou 570228China School of Information Engineering Capital Normal UniversityBeijing 100048China

Illegal construction has caused serious harm around the world. However, current methods are difficult to detect illegal construction activities in time, and the calculation complexity and the parameters of them are large. To solve these challenges, a new and unique detection method is proposed, which detects objects related to illegal buildings in time to discover illegal construction activities. Meanwhile, a new dataset and a high-precision and lightweight detector are proposed. The proposed detector is based on the algorithm You Only Look Once (YOLOv4). The use of DenseNet as the backbone of YDHNet enables better feature transfer and reuse, improves detection accuracy, and reduces computational costs. Meanwhile, depthwise separable convolution is employed to lightweight the neck and head to further reduce computational costs. Furthermore, H-swish is utilized to enhance non-linear feature extraction and improve detection accuracy. Experimental results illustrate that YDHNet realizes a mean average precision of 89.60% on the proposed dataset, which is 3.78% higher than YOLOv4. The computational cost and parameter count of YDHNet are 26.22 GFLOPs and 16.18 MB, respectively. Compared to YOLOv4 and other detectors, YDHNet not only has lower computational costs and higher detection accuracy, but also timely identifies illegal construction objects and automatically detects illegal construction activities.

关键词： object detection lightweight illegal buildings illegal construction objects high-precision

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

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The symmetric space,strong isotropy irreducibility and equigeodesic properties

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Science China Mathematics 2024年第1期67卷 129-148页

作者： Ming Xu Ju Tan School of Mathematical Sciences Capital Normal UniversityBeijing 100048China School of Microelectronics and Data Science Anhui University of TechnologyMa'anshan 243032China

A smooth curve on a homogeneous manifold G/H is called a Riemannian equigeodesic if it is a homogeneous geodesic for any G-invariant Riemannian *** homogeneous manifold G/H is called Riemannian equigeodesic,if for any x∈G/H and any nonzero y∈Tx(G/H),there exists a Riemannian equigeodesic c(t) with c(0)=x and ■(0)=*** two notions can be naturally transferred to the Finsler setting,which provides the definitions for Finsler equigeodesics and Finsler equigeodesic *** prove two classification theorems for Riemannian equigeodesic spaces and Finsler equigeodesic spaces,***,a homogeneous manifold G/H with a connected simply connected quasi compact G and a connected H is Riemannian equigeodesic if and only if it can be decomposed as a product of Euclidean factors and compact strongly isotropy irreducible ***,a homogeneous manifold G/H with a compact semisimple G is Finsler equigeodesic if and only if it can be locally decomposed as a product,in which each factor is Spin(7)/G2,G2/SU (3) or a symmetric space of compact *** results imply that the symmetric space and the strongly isotropy irreducible space of compact type can be interpreted by equigeodesic *** an application,we classify the homogeneous manifold G/H with a compact semisimple G such that all the G-invariant Finsler metrics on G/H are *** suggests a new project in homogeneous Finsler geometry,i.e.,to systematically study the homogeneous manifold G/H on which all the G-invariant Finsler metrics satisfy a certain geometric property.

关键词： equigeodesic equigeodesic space flag manifold orbit type stratification symmetric space strongly isotropy irreducible space

Designing simple non-fused terthiophene-based electron acceptors for efficient organic solar cells

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Journal of Energy Chemistry 2024年第9期96卷 501-508页

作者： Jiayu Li Kun Li Zhe Mei Yu Chen Qian Xie Chenxu Yu Xuefeng Liu Yanqi Wang Yishi Wu Qing Liao Cunbin An Hongbing Fu beijing Key Laboratory for Optical Materials and Photonic Devices Department of ChemistryCapital Normal UniversityBeijing 100048China beijing Synchrotron Radiation Laboratory Institute of High Energy PhysicsChinese Academy of Sciences(CAS)Beijing 100049China

Low-cost photovoltaic materials are essential for realizing large-scale commercial applications of organic solar cells(OSCs).However,highly efficient OSCs based on low-cost photovoltaic materials are scarce due to a deficiency in understanding the structure-property ***,we investigated two low-cost terthiophene-based electron acceptors,namely,3TC8 and 3TEH,with 3,4-bis(octan-3-yloxy)thiophene,differing only in the alkylated *** acceptors exhibit low optical gaps(∼1.43 eV)and possess deep highest occupied molecular orbital(HOMO)levels(∼−5.8 eV).Notably,the single-crystal structure of 3TEH demonstrates highly planar conjugated backbone and strongπ-πstacking between intermolecular terminal groups,attributed to the presence of the bulky alkylated noncovalently conformational *** utilizing both acceptors to fabricate OSCs,the 3TC8-based device exhibited a power conversion efficiency(PCE)of 11.1%,while the 3TEH-based OSC demonstrated an excellent PCE of 14.4%.This PCE is the highest among OSCs based on terthiophene-containing electron *** results offer a new strategy for designing low-cost electron acceptors for highly efficient OSCs.

关键词： Organic solarcells Low cost Terthiophene Non-fused electron acceptor

Event-triggered H_(∞) consensus control for input-constrained multi-agent systems via reinforcement learning

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Control Theory and Technology 2024年第1期22卷 25-38页

作者： Jinxuan Zhang Chang-E Ren College of Information Engineering Capital Normal UniversityBeijing100089China

This article presents an event-triggered H_(∞) consensus control scheme using reinforcement learning (RL) for nonlinear second-order multi-agent systems (MASs) with control constraints. First, considering control constraints, the constrained H_(∞) consensus problem is transformed into a multi-player zero-sum game with non-quadratic performance functions. Then, an event-triggered control method is presented to conserve communication resources and a new triggering condition is developed for each agent to make the triggering threshold independent of the disturbance attenuation level. To derive the optimal controller that can minimize the cost function in the case of worst disturbance, a constrained Hamilton–Jacobi–Bellman (HJB) equation is defined. Since it is difficult to solve analytically due to its strongly non-linearity, reinforcement learning (RL) is implemented to obtain the optimal controller. In specific, the optimal performance function and the worst-case disturbance are approximated by a time-triggered critic network;meanwhile, the optimal controller is approximated by event-triggered actor network. After that, Lyapunov analysis is utilized to prove the uniformly ultimately bounded (UUB) stability of the system and that the network weight errors are UUB. Finally, a simulation example is utilized to demonstrate the effectiveness of the control strategy provided.

关键词： H_(∞)optimal control Input constrains Multi-agent systems(MASs) Reinforcement learning(RL)

Magneto-optic Kerr Effect Measurement of TbMn_(6)Sn_(6) at mK Temperature

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Chinese Physics Letters 2024年第4期41卷 159-163页

作者：黄代强汪洋王贺王健刘阳 International Center for Quantum Materials Peking UniversityBeijing 100871China Department of Physics Capital Normal UniversityBeijing 100048China Collaborative Innovation Center of Quantum Matter Beijing 100871China Hefei National Laboratory Hefei 230088China

Novel electron states stabilized by Coulomb interactions attract tremendous interests in condensed matter *** states are studied by corresponding phase transitions occurring at extreme conditions such as mK temperatures and high magnetic *** this work,we introduce a magneto-optical Kerr effect measurement system to comprehensively explore these phases in addition to conventional transport *** system,composed of an all-fiber zero-loop Sagnac interferometer and in situ piezo-scanner inside a dilution refrigerator,operates below 100 m K,with a maximum field of 12 Tesla and has a resolution as small as 0.2μ*** a demonstration,we investigate TbMn_(6)Sn_(6),where the manganese atoms form Kagome lattice that hosts topological non-trivial Dirac *** observed two types of Kerr signals,stemming from its fully polarized ferromagnetic ground state and positive charged carriers within the Dirac-like dispersion.

关键词： interferometer scanner system

Tighter sum uncertainty relations via(α,β,γ)weighted Wigner–Yanase–Dyson skew information

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Communications in Theoretical Physics 2024年第3期76卷 91-99页

作者： Cong Xu Zhaoqi Wu Shao-Ming Fei School of Mathematical Sciences Capital Normal UniversityBeijing 100048China Department of Mathematics Nanchang UniversityNanchang 330031China Max-Planck-Institute for Mathematics in the Sciences 04103 LeipzigGermany

We establish tighter uncertainty relations for arbitrary finite observables via(α,β,γ)weighted Wigner–Yanase–Dyson((α,β,γ)WWYD)skew *** results are also applicable to the(α,γ)weighted Wigner–Yanase–Dyson((α,γ)WWYD)skew information and the weighted Wigner–Yanase–Dyson(WWYD)skew *** also present tighter lower bounds for quantum channels and unitary channels via(α,β,γ)modified weighted Wigner–Yanase–Dyson((α,β,γ)MWWYD)skew *** examples are provided to illustrate the tightness of our uncertainty relations.

关键词： quantum channels (α,β,γ)WWYD skew information (α,β,γ)MWWYD skew information uncertainty relations