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Wiener-Hopf Factorization of a Class of Matrix Functions and Corona Theorem 被引量:1
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作者 GUO Guoan DU Jinyuan 《Wuhan University Journal of Natural Sciences》 CAS 2009年第1期1-5,共5页
By using the Riemann-Hilbert method and the Corona theorem, Wiener-Hopf factorization for a class of matrix functions is studied. Under appropriate assumption, a sufficient and neces- sary condition for the existence ... By using the Riemann-Hilbert method and the Corona theorem, Wiener-Hopf factorization for a class of matrix functions is studied. Under appropriate assumption, a sufficient and neces- sary condition for the existence of the matrix function admitting canonical factorization is obtained and the solution to a class of non-linear Riemann-Hilbert problems is also given. Furthermore, by means of non-standard Corona theorem partial estimation of the general factorization can be obtained. 展开更多
关键词 Riemann-Hilbert problem Hardy space Corona theorem canonical factorization projector operator
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Herglotz type Noether theorems of nonholonomic systems with generalized fractional derivatives 被引量:1
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作者 Yuan-Yuan Deng Yi Zhang 《Theoretical & Applied Mechanics Letters》 2025年第2期179-187,共9页
Fractional calculus is widely used to deal with nonconservative dynamics because of its memorability and non-local properties.In this paper,the Herglotz principle with generalized operators is discussed,and the Herglo... Fractional calculus is widely used to deal with nonconservative dynamics because of its memorability and non-local properties.In this paper,the Herglotz principle with generalized operators is discussed,and the Herglotz type equations for nonholonomic systems are established.Then,the Noether symmetries are studied,and the conserved quantities are obtained.The results are extended to nonholonomic canonical systems,and the Herglotz type canonical equations and the Noether theorems are obtained.Two examples are provided to demonstrate the validity of the methods and results. 展开更多
关键词 Nonholonomic system Herglotz principle Noether theorem Generalized operators
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The Paley-Wiener Theorem for General Weighted Hardy Spaces on Tube Domains
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作者 HUANG Yun ZHANG Dawei 《应用数学》 北大核心 2025年第3期841-849,共9页
In this paper,the Paley-Wiener theorem is extended to the analytic function spaces with general weights.We first generalize the theorem to weighted Hardy spaces Hp(0<p<∞)on tube domains by constructing a sequen... In this paper,the Paley-Wiener theorem is extended to the analytic function spaces with general weights.We first generalize the theorem to weighted Hardy spaces Hp(0<p<∞)on tube domains by constructing a sequence of L^(1)functions converging to the given function and verifying their representation in the form of Fourier transform to establish the desired result of the given function.Applying this main result,we further generalize the Paley-Wiener theorem for band-limited functions to the analytic function spaces L^(p)(0<p<∞)with general weights. 展开更多
关键词 Paley-Wiener theorem Fourier transform Weighted Hardy space Tube domain
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Source apportionment of PM_(2.5) using dispersion normalized positive matrix factorization(DN-PMF)in Beijing and Baoding,China 被引量:1
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作者 Ilhan Ryoo Taeyeon Kim +6 位作者 Jiwon Ryu Yeonseung Cheong Kwang-joo Moon Kwon-ho Jeon Philip K.Hopke Seung-Muk Yi Jieun Park 《Journal of Environmental Sciences》 2025年第9期395-408,共14页
Fine particulatematter(PM_(2.5))samples were collected in two neighboring cities,Beijing and Baoding,China.High-concentration events of PM_(2.5) in which the average mass concentration exceeded 75μg/m^(3) were freque... Fine particulatematter(PM_(2.5))samples were collected in two neighboring cities,Beijing and Baoding,China.High-concentration events of PM_(2.5) in which the average mass concentration exceeded 75μg/m^(3) were frequently observed during the heating season.Dispersion Normalized Positive Matrix Factorization was applied for the source apportionment of PM_(2.5) as minimize the dilution effects of meteorology and better reflect the source strengths in these two cities.Secondary nitrate had the highest contribution for Beijing(37.3%),and residential heating/biomass burning was the largest for Baoding(27.1%).Secondary nitrate,mobile,biomass burning,district heating,oil combustion,aged sea salt sources showed significant differences between the heating and non-heating seasons in Beijing for same period(2019.01.10–2019.08.22)(Mann-Whitney Rank Sum Test P<0.05).In case of Baoding,soil,residential heating/biomass burning,incinerator,coal combustion,oil combustion sources showed significant differences.The results of Pearson correlation analysis for the common sources between the two cities showed that long-range transported sources and some sources with seasonal patterns such as oil combustion and soil had high correlation coefficients.Conditional Bivariate Probability Function(CBPF)was used to identify the inflow directions for the sources,and joint-PSCF(Potential Source Contribution Function)was performed to determine the common potential source areas for sources affecting both cities.These models facilitated a more precise verification of city-specific influences on PM_(2.5) sources.The results of this study will aid in prioritizing air pollution mitigation strategies during the heating season and strengthening air quality management to reduce the impact of downwind neighboring cities. 展开更多
关键词 Source apportionment Dispersion normalized positive matrix factorization Adjacent cities Inter-city impact Source location Heating season Air quality management
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A Metamodeling Approach to Enforcing the No-Cloning Theorem in Quantum Software Engineering
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作者 Dae-Kyoo Kim 《Computers, Materials & Continua》 2025年第8期2549-2572,共24页
Quantum software development utilizes quantum phenomena such as superposition and entanglement to address problems that are challenging for classical systems.However,it must also adhere to critical quantum constraints... Quantum software development utilizes quantum phenomena such as superposition and entanglement to address problems that are challenging for classical systems.However,it must also adhere to critical quantum constraints,notably the no-cloning theorem,which prohibits the exact duplication of unknown quantum states and has profound implications for cryptography,secure communication,and error correction.While existing quantum circuit representations implicitly honor such constraints,they lack formal mechanisms for early-stage verification in software design.Addressing this constraint at the design phase is essential to ensure the correctness and reliability of quantum software.This paper presents a formal metamodeling framework using UML-style notation and and Object Constraint Language(OCL)to systematically capture and enforce the no-cloning theorem within quantum software models.The proposed metamodel formalizes key quantum concepts—such as entanglement and teleportation—and encodes enforceable invariants that reflect core quantum mechanical laws.The framework’s effectiveness is validated by analyzing two critical edge cases—conditional copying with CNOT gates and quantum teleportation—through instance model evaluations.These cases demonstrate that the metamodel can capture nuanced scenarios that are often mistaken as violations of the no-cloning theorem but are proven compliant under formal analysis.Thus,these serve as constructive validations that demonstrate the metamodel’s expressiveness and correctness in representing operations that may appear to challenge the no-cloning theorem but,upon rigorous analysis,are shown to comply with it.The approach supports early detection of conceptual design errors,promoting correctness prior to implementation.The framework’s extensibility is also demonstrated by modeling projective measurement,further reinforcing its applicability to broader quantum software engineering tasks.By integrating the rigor of metamodeling with fundamental quantum mechanical principles,this work provides a structured,model-driven approach that enables traditional software engineers to address quantum computing challenges.It offers practical insights into embedding quantum correctness at the modeling level and advances the development of reliable,error-resilient quantum software systems. 展开更多
关键词 METAMODELING no-cloning theorem quantum software software engineering
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Scaling Rule,Energy Distribution and Energy Level Analysis for Morse Oscillator by Virtue of Hermann-Feynman Theorem
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作者 Zhi-Long Wan Jun-Hua Chen Hong-Yi Fan 《Chinese Journal of Chemical Physics》 2025年第3期368-372,I0109,共6页
We propose the scaling rule of Morse oscillator,based on this rule and by virtue of the Her-mann-Feymann theorem,we respectively obtain the distribution of potential and kinetic ener-gy of the Morse Hamiltonian.Also,w... We propose the scaling rule of Morse oscillator,based on this rule and by virtue of the Her-mann-Feymann theorem,we respectively obtain the distribution of potential and kinetic ener-gy of the Morse Hamiltonian.Also,we derive the exact upper limit of physical energy level.Further,we derive some recursive relations for energy matrix elements of the potential and other similar operators in the context of Morse oscillator theory. 展开更多
关键词 Morse oscillator Scaling rule Hermann-Feynman theorem
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Neural Tucker Factorization
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作者 Peng Tang Xin Luo 《IEEE/CAA Journal of Automatica Sinica》 2025年第2期475-477,共3页
Dear Editor,This letter presents a novel latent factorization model for high dimensional and incomplete (HDI) tensor, namely the neural Tucker factorization (Neu Tuc F), which is a generic neural network-based latent-... Dear Editor,This letter presents a novel latent factorization model for high dimensional and incomplete (HDI) tensor, namely the neural Tucker factorization (Neu Tuc F), which is a generic neural network-based latent-factorization-of-tensors model under the Tucker decomposition framework. 展开更多
关键词 neu tuc f neural tucker factorization latent factorization model high dimensional tensor tucker decomposition framework neural network incomplete tensor latent factorization
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ECHOS OF THE STEINER-LEHMUS EQUAL BISECTORS THEOREM
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作者 Christoph BÖRGERS Eric L.GRINBERG +1 位作者 Mehmet ORHON Junhao SHEN 《Acta Mathematica Scientia》 2025年第1期257-263,共7页
The Steiner-Lehmus equal bisectors theorem originated in the mid 19th century.Despite its age,it would have been accessible to Euclid and his contemporaries.The theorem remains evergreen,with new proofs continuing to ... The Steiner-Lehmus equal bisectors theorem originated in the mid 19th century.Despite its age,it would have been accessible to Euclid and his contemporaries.The theorem remains evergreen,with new proofs continuing to appear steadily.The theorem has fostered discussion about the nature of proof itself,direct and indirect.Here we continue the momentum by providing a trigonometric proof,relatively short,based on an analytic estimate that leverages algebraic trigonometric identities.Many proofs of the theorem exist in the literature.Some of these contain key ideas that already appeared in C.L.Lehmus’1850 proofs,not always with citation.In the aim of increasing awareness of and making more accessible Lehmus’proofs,we provide an annotated translation.We conclude with remarks on different proofs and relations among them. 展开更多
关键词 Steiner-Lehmus theorem equal bisectors
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SZEG TYPE FACTORIZATION THEOREM FOR NONCOMMUTATIVE HARDY-LORENTZ SPACES 被引量:5
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作者 邵晶晶 韩亚洲 《Acta Mathematica Scientia》 SCIE CSCD 2013年第6期1675-1684,共10页
We introduce noncommutative Hardy-Lorentz spaces and give the Szegō and inner-outer type factorizations of these spaces.
关键词 subdiagonal algebras noncommutative Hardy-Lorentz spaces Szegō factor-ization outer operators
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Changes in factor profiles deriving from photochemical losses of volatile organic compounds:Insight from daytime and nighttime positive matrix factorization ana
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作者 Baoshuang Liu Tao Yang +9 位作者 Sicong Kang Fuquan Wang Haixu Zhang Man Xu Wei Wang Jinrui Bai Shaojie Song Qili Dai Yinchang Feng Philip K.Hopke 《Journal of Environmental Sciences》 2025年第5期627-639,共13页
Substantial effects of photochemical reaction losses of volatile organic compounds(VOCs)on factor profiles can be investigated by comparing the differences between daytime and nighttime dispersion-normalized VOC data ... Substantial effects of photochemical reaction losses of volatile organic compounds(VOCs)on factor profiles can be investigated by comparing the differences between daytime and nighttime dispersion-normalized VOC data resolved profiles.Hourly speciated VOC data measured in Shijiazhuang,China from May to September 2021 were used to conduct study.The mean VOC concentration in the daytime and at nighttime were 32.8 and 36.0 ppbv,respectively.Alkanes and aromatics concentrations in the daytime(12.9 and 3.08 ppbv)were lower than nighttime(15.5 and 3.63 ppbv),whereas that of alkenes showed the opposite tendency.The concentration differences between daytime and nighttime for alkynes and halogenated hydrocarbonswere uniformly small.The reactivities of the dominant species in factor profiles for gasoline emissions,natural gas and diesel vehicles,and liquefied petroleum gas were relatively low and their profiles were less affected by photochemical losses.Photochemical losses produced a substantial impact on the profiles of solvent use,petrochemical industry emissions,combustion sources,and biogenic emissions where the dominant species in these factor profiles had high reactivities.Although the profile of biogenic emissions was substantially affected by photochemical loss of isoprene,the low emissions at nighttime also had an important impact on its profile.Chemical losses of highly active VOC species substantially reduced their concentrations in apportioned factor profiles.This study results were consistent with the analytical results obtained through initial concentration estimation,suggesting that the initial concentration estimation could be the most effective currently availablemethod for the source analyses of active VOCs although with uncertainty. 展开更多
关键词 Volatile organic compounds Dispersion normalization Photochemical loss Factor profile Positive matrix factorization
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LIOUVILLE THEOREM FOR 3D STATIONARY Q-TENSOR SYSTEM OF LIQUID CRYSTAL
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作者 HU Li-li ZHOU Yan-ping BIE Qun-yi 《数学杂志》 2025年第4期283-292,共10页
In this paper,we study Liouville theorem for the 3D stationary Q-tensor system of liquid crystal in Lorentz and Morrey spaces.Under some additional hypotheses,stated in terms of Lorentz and Morrey spaces,using energy ... In this paper,we study Liouville theorem for the 3D stationary Q-tensor system of liquid crystal in Lorentz and Morrey spaces.Under some additional hypotheses,stated in terms of Lorentz and Morrey spaces,using energy estimation,we obtain that the trivial solution u=Q=0 is the unique solution.Our theorems correspond to improvements of some recent results and contain some known results as particular cases. 展开更多
关键词 Lorentz spaces Morrey spaces Q-tensor liquid crystal Liouville theorem
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VANISHING THEOREMS OF THE BASIC P-HARMONIC FORMS ON COMPLETE FOLIATED RIEMANNIAN MANIFOLDS
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作者 NIE Yan-ci SHEN Zheng-han 《数学杂志》 2025年第3期195-204,共10页
In this paper,we study the basic p-harmonic forms on the complete foliated Riemannian manifolds.By using the method in[1],we show that if the basic mean curvature form is bounded and co-closed,and the transversal curv... In this paper,we study the basic p-harmonic forms on the complete foliated Riemannian manifolds.By using the method in[1],we show that if the basic mean curvature form is bounded and co-closed,and the transversal curvature operator is nonnegative and positive at least one point,then we obtain a vanishing theorem for L^(p)-integrably p-harmonic r-forms. 展开更多
关键词 basic p-harmonic form vanishing theorem foliated Riemannian manifold
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A VECTOR BUNDLE VALUED MIXED HARD LEFSCHETZ THEOREM
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作者 Zeng CHEN Guanxiang WANG 《Acta Mathematica Scientia》 2025年第2期514-524,共11页
In this paper,we obtain a vector bundle valued mixed hard Lefschetz theorem.The argument is mainly based on the works of Tien-Cuong Dinh and Viet-Anh Nguyen.
关键词 hard Lefschetz theorem holomorphic vector bundle Hermitian fat vector bundle
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Sub-Riemannian Limits,Connections with Torsion and the Gauss-Bonnet Theorem for Four Dimensional Twisted BCV Spaces
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作者 LI Hong-feng LIU Ke-feng WANG Yong 《Chinese Quarterly Journal of Mathematics》 2025年第2期111-134,共24页
In this paper,we compute sub-Riemannian limits of some important curvature variants associated with the connection with torsion for four dimensional twisted BCV spaces and derive a Gauss-Bonnet theorem for four dimens... In this paper,we compute sub-Riemannian limits of some important curvature variants associated with the connection with torsion for four dimensional twisted BCV spaces and derive a Gauss-Bonnet theorem for four dimensional twisted BCV spaces. 展开更多
关键词 Gauss-Bonnet theorem Sub-Riemannian limit Twisted BCV spaces Orthogonal connections with torsion
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Liouville Theorem for 3D Steady Q-Tensor System of Liquid Crystal in Mixed Lorentz Spaces
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作者 WAN Mengru DENG Xuemei BIE Qunyi 《Wuhan University Journal of Natural Sciences》 2025年第3期235-240,共6页
this paper,we study Liouville theorem for 3D steady Q-tensor system of liquid crystal in mixed Lorentz spaces.We obtain u=0,Q=0 on the conditions that μ∈L^(p,∞x_(1)L^(q,∞x_(2)L^(r,∞x_(3)(R^(4)∩H^(1)(R^(3),Q∈H^(... this paper,we study Liouville theorem for 3D steady Q-tensor system of liquid crystal in mixed Lorentz spaces.We obtain u=0,Q=0 on the conditions that μ∈L^(p,∞x_(1)L^(q,∞x_(2)L^(r,∞x_(3)(R^(4)∩H^(1)(R^(3),Q∈H^(2)(R^(3),p,q,r∈(3,∞],and 1/p+1/q+1/r≥2/3, which extends some known results. 展开更多
关键词 mixed Lorentz spaces Q-tensor system of liquid crystal Liouville theorem
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Research on Library Data Governance for Data Factorization
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作者 Yan Jiang 《Journal of Electronic Research and Application》 2025年第6期159-166,共8页
Data factors are becoming the core driving force in the intelligent transformation of libraries.Based on a systematic review of the progress in data governance practices in libraries both domestically and internationa... Data factors are becoming the core driving force in the intelligent transformation of libraries.Based on a systematic review of the progress in data governance practices in libraries both domestically and internationally,this study delves into the mechanism by which data governance promotes data factorization and proposes implementation paths for data governance oriented toward data factorization.The aim is to facilitate the intelligent transformation and high-quality development of libraries. 展开更多
关键词 Data factorization LIBRARIES Data governance Mechanism of action Practical paths
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Predicting CircRNA-Disease Associations via Non-Negative Matrix Factorization Fused with Multiple Similarity Networks
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作者 LU Pengli LI Shiying 《Journal of Shanghai Jiaotong university(Science)》 2025年第4期709-719,共11页
CircRNAs,widely found throughout the human bodies,play a crucial role in regulating various biological processes and are closely linked to complex human diseases.Investigating potential associations between circRNAs a... CircRNAs,widely found throughout the human bodies,play a crucial role in regulating various biological processes and are closely linked to complex human diseases.Investigating potential associations between circRNAs and diseases can enhance our understanding of diseases and provide new strategies and tools for early diagnosis,treatment,and disease prevention.However,existing models have limitations in accurately capturing similarities,handling the sparse and noise attributes of association networks,and fully leveraging bioinformatical aspects from multiple viewpoints.To address these issues,this study introduces a new non-negative matrix factorization-based framework called NMFMSN.First,we incorporate circRNA sequence data and disease semantic information to compute circRNA and disease similarity,respectively.Given the sparse known associations between circRNAs and diseases,we reconstruct the network to complete more associations by imputing missing links based on neighboring circRNA and disease interactions.Finally,we integrate these two similarity networks into a non-negative matrix factorization framework to identify potential circRNA-disease associations.Upon conducting 5-fold cross-validation and leave-one-out cross-validation,the AUC values for NMFMSN reach 0.9712 and 0.9768,respectively,outperforming the currently most advanced models.Case studies on lung cancer and hepatocellular carcinoma show that NMFMSN is a good way to predict new associations between circRNAs and diseases. 展开更多
关键词 circRNA-disease associations circRNA sequence data disease semantic information non-negative matrix factorization
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Nonlinear Control for Unstable Networked Plants in the Presence of Actuator and Sensor Limitations Using Robust Right Coprime Factorization
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作者 Yuanhong Xu Mingcong Deng 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期516-527,共12页
In this paper,a nonlinear control approach for an unstable networked plant in the presence of actuator and sensor limitations using robust right coprime factorization is proposed.The actuator is limited by upper and l... In this paper,a nonlinear control approach for an unstable networked plant in the presence of actuator and sensor limitations using robust right coprime factorization is proposed.The actuator is limited by upper and lower constraints and the sensor in the feedback loop is subjected to network-induced unknown time-varying delay and noise.With this nonlinear control method,we first employ right coprime factorization based on isomorphism and operator theory to factorize the plant,so that bounded input bounded output(BIBO)stability can be guaranteed.Next,continuous-time generalized predictive control(CGPC)is utilized for the unstable operator of the right coprime factorized plant to guarantee inner stability and enables the closed-loop dynamics of the system with predictive characteristics.Meanwhile,a second-Do F(degrees of freedom)switched controller that satisfies a perturbed Bezout identity and a robustness condition is designed.By using the CGPC controller that possesses predictive behavior and the second-Do F switched stabilizer,the overall stability of the plant subjected to actuator limitations is guaranteed.To address sensor limitations that exist in networked plants in the form of delay and noise which often cause system performance degradation,we implement an identity operator definition in the feedback loop to compensate for these adverse effects.Further,a pre-operator is designed to ensure that the plant output tracks the reference input.Finally,the effectiveness of the proposed design scheme is demonstrated by simulations. 展开更多
关键词 Actuator and sensor limitations identity operator definition network-induced limitations robust right coprime factorization unstable plant
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Latent-Factorization-of-Tensors-Incorporated Battery Cycle Life Prediction
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作者 Minzhi Chen Li Tao +1 位作者 Jungang Lou Xin Luo 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期633-635,共3页
Dear Editor,This letter presents a latent-factorization-of-tensors(LFT)-incorporated battery cycle life prediction framework.Data-driven prognosis and health management(PHM)for battery pack(BP)can boost the safety and... Dear Editor,This letter presents a latent-factorization-of-tensors(LFT)-incorporated battery cycle life prediction framework.Data-driven prognosis and health management(PHM)for battery pack(BP)can boost the safety and sustainability of a battery management system(BMS),which relies heavily on the quality of the measured BP data like the voltage(V),current(I),and temperature(T). 展开更多
关键词 health management battery pack bp can latent factorization tensors battery cycle life prediction health management phm battery cycle battery pack battery management system bms which
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心内科住院患者并发院内感染的危险因素调查
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作者 陈恒 赵登峰 +1 位作者 李杰 苏珊珊 《中国病原生物学杂志》 北大核心 2026年第1期82-85,共4页
目的分析心内科住院患者并发院内感染的危险因素,探讨炎性因子水平在感染发生中的作用。方法选取2023年1月至2024年12月本院心内科住院的152例合并院内感染患者作为研究对象,并纳入90例未感染患者作为对照组。采集感染患者标本进行病原... 目的分析心内科住院患者并发院内感染的危险因素,探讨炎性因子水平在感染发生中的作用。方法选取2023年1月至2024年12月本院心内科住院的152例合并院内感染患者作为研究对象,并纳入90例未感染患者作为对照组。采集感染患者标本进行病原体分离鉴定,检测血清白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)水平。通过单因素χ2检验和多因素Logistic回归分析感染危险因素。结果152例院内感染患者中,医院获得性肺炎(43.42%)和导管相关血流感染(28.95%)为主要感染类型,共检出病原菌163株,以革兰阴性菌为主(57.67%),其中肺炎克雷伯菌(28.83%)最常见。感染组IL-6和TNF-α水平分别为(113.55±10.29)pg/mL和(88.41±8.38)pg/mL,显著高于非感染组(P<0.05),合并糖尿病患者水平显著高于非糖尿病患者(P<0.05)。单因素分析显示,年龄≥65岁、合并糖尿病、慢性肾病、COPD、侵入性操作≥2项、抗菌药物使用≥10 d及PPI使用与感染相关(P<0.05);多因素Logistic回归表明,年龄≥65岁(OR=19.652)、合并糖尿病(OR=11.926)、COPD(OR=6.399)、侵入性操作≥2项(OR=14.035)、抗菌药物使用≥10 d(OR=13.956)为独立危险因素(P<0.05)。结论心内科住院患者院内感染以革兰阴性菌为主,高龄、糖尿病、COPD、侵入性操作及长期抗菌药物使用是重要危险因素,监测炎性因子水平或可辅助感染评估,临床需针对高危因素制定防控策略。 展开更多
关键词 心内科 院内感染 危险因素 病原谱 炎性因子
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