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Quality of primary total knee arthroplasty operative reports in a tertiary teaching hospital
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作者 Sulaiman A Almousa 《World Journal of Orthopedics》 2025年第5期61-71,共11页
BACKGROUND Operative reports(OP-Rs)are essential for communication among healthcare providers.They require accuracy and completeness to serve as a quality indicator of patient care.Objective assessment of primary tota... BACKGROUND Operative reports(OP-Rs)are essential for communication among healthcare providers.They require accuracy and completeness to serve as a quality indicator of patient care.Objective assessment of primary total knee replacement(TKR)OP-Rs has never been reported.Therefore,a standardized benchmark for assessment and factors affecting the completeness of TKR OP-Rs needs to be evaluated.AIM To evaluate the completeness rate of primary TKR OP-Rs in a teaching hospital and to assess the factors affecting completeness.METHODS A retrospective review of 58 consecutive primary TKR OP-Rs in a tertiary te-aching hospital were included in this study.We used document analysis to review the OP-Rs against a standardized list of six subsets of mandatory variables.The correlation between the percentage of completeness and the specific variables was determined.RESULTS After analyzing 58 cases,we found that the time to documentation was 1.5 hours.Out of the 52 mandatory variables,a median of 30 variables were documented yielding a completeness of 58%.Administrative,procedural,exposure,and im-plant variables were documented the most often,whereas clinical and process variables were most frequently left uncompleted.The documentation of the operative maneuver was variable.There was no association between the com-pleteness of the reports and the time to documentation,documenter level,com-plication rate,operative duration,or length of hospital stay.CONCLUSION Multiple variables were left undocumented on the unstructured primary TKR OP-Rs.The completeness percentage will likely improve after the implementation of a standardized structured OP-R. 展开更多
关键词 operative report documentation operative report quality Total knee replacement operative documentation Completeness of operative reports operative reporting training
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Hyponormal Block Toeplitz Operators on the Weighted Bergman Space with Circulant Symbols
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作者 FU Guangyang ZHOU Jiang 《数学进展》 北大核心 2026年第1期183-191,共9页
In this paper,we present a necessary and sufficient condition for hyponormal block Toeplitz operators T on the vector-valued weighted Bergman space with symbolsΦ(z)=G^(*)(z)+F(z),where F(z)=∑^(N)_(i)=1 A_(i)z^(i)and... In this paper,we present a necessary and sufficient condition for hyponormal block Toeplitz operators T on the vector-valued weighted Bergman space with symbolsΦ(z)=G^(*)(z)+F(z),where F(z)=∑^(N)_(i)=1 A_(i)z^(i)and G(z)=∑^(N)_(i)=1 A_(−i)z^(i),A_(i)ae culants. 展开更多
关键词 block Toeplitz operator hyponormal weighted Bergman space CIRCULANT COMMUTATOR
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Cooperative robust parallel operation of multiple actuators
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作者 XU Liang XU Xiang LIU Tao 《控制理论与应用》 北大核心 2026年第1期3-11,共9页
This paper studies cooperative robust parallel operation of multiple actuators over an undirected communication graph.The plant is modeled as an uncertain linear system,and the actuators are linear and identical.Based... This paper studies cooperative robust parallel operation of multiple actuators over an undirected communication graph.The plant is modeled as an uncertain linear system,and the actuators are linear and identical.Based on the internal model principle,a distributed dynamic output feedback control law is proposed to achieve both robust output regulation of the closed-loop system and plant input sharing among the actuators.A practical example of five motors cooperatively driving an uncertain shaft under an external load torque is presented to show the effectiveness of the proposed control law. 展开更多
关键词 cooperative parallel operation multiple actuators robust output regulation CONSENSUS
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A GENERALIZED HILBERT OPERATOR ACTING ON HARDY SPACES
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作者 Huiling CHEN Shanli YE 《Acta Mathematica Scientia》 2026年第1期145-163,共19页
Letα>0 and letμbe a positive Borel measure on the interval[0,1).The Hankel matrix■with entries■induces,formally,the generalized-Hilbert operator■where f(z)■is an analytic function in D.This article is devoted... Letα>0 and letμbe a positive Borel measure on the interval[0,1).The Hankel matrix■with entries■induces,formally,the generalized-Hilbert operator■where f(z)■is an analytic function in D.This article is devoted to study the measuresμfor which Hμ,αis a bounded(resp.,compact)operator from Hp(0<p≤1)into H^(p)(1≤q<∞).We also study the analogous problem in the Hardy spaces H^(p)(1≤p≤2).Finally,we obtain the essential norm of H_(μ,α)from H^(p)(0<p≤1)into H^(p)(1≤q<∞). 展开更多
关键词 Hilbert operator Hardy space Carleson measure essential norm
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A Q-Learning Improved Particle Swarm Optimization for Aircraft Pulsating Assembly Line Scheduling Problem Considering Skilled Operator Allocation
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作者 Xiaoyu Wen Haohao Liu +6 位作者 Xinyu Zhang Haoqi Wang Yuyan Zhang Guoyong Ye Hongwen Xing Siren Liu Hao Li 《Computers, Materials & Continua》 2026年第1期1503-1529,共27页
Aircraft assembly is characterized by stringent precedence constraints,limited resource availability,spatial restrictions,and a high degree of manual intervention.These factors lead to considerable variability in oper... Aircraft assembly is characterized by stringent precedence constraints,limited resource availability,spatial restrictions,and a high degree of manual intervention.These factors lead to considerable variability in operator workloads and significantly increase the complexity of scheduling.To address this challenge,this study investigates the Aircraft Pulsating Assembly Line Scheduling Problem(APALSP)under skilled operator allocation,with the objective of minimizing assembly completion time.A mathematical model considering skilled operator allocation is developed,and a Q-Learning improved Particle Swarm Optimization algorithm(QLPSO)is proposed.In the algorithm design,a reverse scheduling strategy is adopted to effectively manage large-scale precedence constraints.Moreover,a reverse sequence encoding method is introduced to generate operation sequences,while a time decoding mechanism is employed to determine completion times.The problem is further reformulated as a Markov Decision Process(MDP)with explicitly defined state and action spaces.Within QLPSO,the Q-learning mechanism adaptively adjusts inertia weights and learning factors,thereby achieving a balance between exploration capability and convergence performance.To validate the effectiveness of the proposed approach,extensive computational experiments are conducted on benchmark instances of different scales,including small,medium,large,and ultra-large cases.The results demonstrate that QLPSO consistently delivers stable and high-quality solutions across all scenarios.In ultra-large-scale instances,it improves the best solution by 25.2%compared with the Genetic Algorithm(GA)and enhances the average solution by 16.9%over the Q-learning algorithm,showing clear advantages over the comparative methods.These findings not only confirm the effectiveness of the proposed algorithm but also provide valuable theoretical references and practical guidance for the intelligent scheduling optimization of aircraft pulsating assembly lines. 展开更多
关键词 Aircraft pulsating assembly lines skilled operator reinforcement learning PSO reverse scheduling
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Splitting of Operations for Di-Associative Algebras and Tri-Associative Algebras
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作者 Wen TENG Xiansheng DAI 《Journal of Mathematical Research with Applications》 2026年第1期21-32,共12页
Loday introduced di-associative algebras and tri-associative algebras motivated by periodicity phenomena in algebraic K-theory.The purpose of this paper is to study the splittings of operations on di-associative algeb... Loday introduced di-associative algebras and tri-associative algebras motivated by periodicity phenomena in algebraic K-theory.The purpose of this paper is to study the splittings of operations on di-associative algebras and tri-associative algebras.We introduce the notion of a quad-dendriform algebra,which is a splitting of a di-associative algebra.We show that a relative averaging operator on dendriform algebras gives rise to a quad-dendriform algebra.Furthermore,we introduce the notion of six-dendriform algebras,which are splittings of the tri-associative algebras,and demonstrate that homomorphic relative averaging operators induce six-dendriform algebras. 展开更多
关键词 dendriform algebra di-associative algebra quad-dendriform algebra tri-associative algebra six-dendriform algebra relative averaging operator
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Research on Operation Strategies of Trade Publishing Knowledge Service Platform Based on the SICAS Model:A Case Study of CITIC Academy
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作者 WANG Jun ZHOU Xiaoyi 《Cultural and Religious Studies》 2026年第1期13-21,共9页
Amidst evolving user behavior driven by the development of the internet,enhancing the operational quality of trade publishing knowledge service platforms has become a significant challenge for publishing institutions.... Amidst evolving user behavior driven by the development of the internet,enhancing the operational quality of trade publishing knowledge service platforms has become a significant challenge for publishing institutions.To address this issue,this paper employs a combined approach of theoretical analysis and case study,introducing the SICAS(Sense-Interest-Connection-Action-Share)user consumption behavior analysis model and selecting“CITIC Academy”as the case study subject.It systematically examines and summarizes the platform’s operational practices and specific strategies,aiming to offer strategic insights and practical references for the operational improvement and sustainable,high-quality development of trade publishing knowledge service platforms. 展开更多
关键词 trade publishing knowledge service platform SICAS model operation strategy CITIC Academy
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Deep reinforcement learning-based adaptive collision avoidance method for UAV in joint operational airspace
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作者 Yan Shen Xuejun Zhang +1 位作者 Yan Li Weidong Zhang 《Defence Technology(防务技术)》 2026年第2期142-159,共18页
As joint operations have become a key trend in modern military development,unmanned aerial vehicles(UAVs)play an increasingly important role in enhancing the intelligence and responsiveness of combat systems.However,t... As joint operations have become a key trend in modern military development,unmanned aerial vehicles(UAVs)play an increasingly important role in enhancing the intelligence and responsiveness of combat systems.However,the heterogeneity of aircraft,partial observability,and dynamic uncertainty in operational airspace pose significant challenges to autonomous collision avoidance using traditional methods.To address these issues,this paper proposes an adaptive collision avoidance approach for UAVs based on deep reinforcement learning.First,a unified uncertainty model incorporating dynamic wind fields is constructed to capture the complexity of joint operational environments.Then,to effectively handle the heterogeneity between manned and unmanned aircraft and the limitations of dynamic observations,a sector-based partial observation mechanism is designed.A Dynamic Threat Prioritization Assessment algorithm is also proposed to evaluate potential collision threats from multiple dimensions,including time to closest approach,minimum separation distance,and aircraft type.Furthermore,a Hierarchical Prioritized Experience Replay(HPER)mechanism is introduced,which classifies experience samples into high,medium,and low priority levels to preferentially sample critical experiences,thereby improving learning efficiency and accelerating policy convergence.Simulation results show that the proposed HPER-D3QN algorithm outperforms existing methods in terms of learning speed,environmental adaptability,and robustness,significantly enhancing collision avoidance performance and convergence rate.Finally,transfer experiments on a high-fidelity battlefield airspace simulation platform validate the proposed method's deployment potential and practical applicability in complex,real-world joint operational scenarios. 展开更多
关键词 Unmanned aerial vehicle Collision avoidance Deep reinforcement learning Joint operational airspace Hierarchical prioritized experience replay
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THE BOUNDEDNESS OF INHOMOGENEOUS CALDERÓN-ZYGMUND CONVOLUTION OPERATORS ON LOCAL PRODUCT HARDY SPACES
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作者 Shaoyong HE Jiecheng CHEN 《Acta Mathematica Scientia》 2026年第1期99-111,共13页
It is well known that the inhomogeneous Calderón-Zygmund convolution operators are bounded on the local Hardy spaces.In this paper,we prove that these operators are bounded on the local product Hardy spaces and t... It is well known that the inhomogeneous Calderón-Zygmund convolution operators are bounded on the local Hardy spaces.In this paper,we prove that these operators are bounded on the local product Hardy spaces and the Lipschitz spaces.The key ideas used here are the discrete local Calderón identity and a density argument for the inhomogeneous product Lipschitz spaces in the weak sense. 展开更多
关键词 local Hardy space Lipschitz space inhomogeneous Calderón-Zygmund operator discrete Calderón identity
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What do Hainan’s Island-Wide Special Customs Operations Mean for the World?
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作者 ZHANG JUAN 《China Today》 2026年第3期26-31,共6页
THE Hainan Free Trade Port(FTP)officially launched island-wide special customs operations on December 18,2025.One month in,a reporting team from China International Communications Group(CICG)conducted an exclusive int... THE Hainan Free Trade Port(FTP)officially launched island-wide special customs operations on December 18,2025.One month in,a reporting team from China International Communications Group(CICG)conducted an exclusive interview with Feng Fei,secretary of the Hainan Provincial Committee of the Communist Party of China(CPC)and chairman of the Standing Committee of the Hainan Provincial People’s Congress. 展开更多
关键词 Trade Liberalization Customs Efficiency Economic Development Free Trade Port Policy Hainan Free Trade Port Customs Reform free trade port ftp officially Island wide Special Customs operations
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A Review and Outlook of Bilateral Eco-nomic and Trade Cooperation Against the Backdrop of the 20th Anniversary of the China-Chile Free Trade Agreement
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作者 Gao Shujun Lu Yao 《China's Foreign Trade》 2025年第5期44-52,共9页
Chile,a pioneer and benchmark partner for China's free trade.cooperation in Latin America,holds a special position in China-Latin America economic and trade relations.It was the first Latin American country to sig... Chile,a pioneer and benchmark partner for China's free trade.cooperation in Latin America,holds a special position in China-Latin America economic and trade relations.It was the first Latin American country to sign a bilateral free trade agreement with China and the first to reach an upgraded protocol.Chile also established mutual recognition of Authorized Economic Operators(AEO)with China,the first country in South America to do so. 展开更多
关键词 mutual recognition authorized economic operators aeo bilateral free trade agreement Latin America AEO authorized economic operators bilateral economic cooperation trade agreement China Chile FTA
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Great Prospect for Agricultural Cooperation Between China and Belarus
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作者 Zhao Huirong 《China's Foreign Trade》 2025年第6期25-27,共3页
Belarus is China's all-weather strategic cooperative partner,and agricultural cooperation is a dynamic and important area of bilateral relations.Despite the limited economic scale with a GDP of USD 75.96 billion i... Belarus is China's all-weather strategic cooperative partner,and agricultural cooperation is a dynamic and important area of bilateral relations.Despite the limited economic scale with a GDP of USD 75.96 billion in 2024,Belarus has significant agricultural advantages.It has natural resources and policy support suitable for agriculture,a strong agricultural foundation,and widespread mechanized operations. 展开更多
关键词 strategic cooperative partner BELARUS natural resources agricultural foundation mechanized operations China agricultural cooperation policy support
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Holder’s inequalities for a class of analytic functions connected with a certain hybrid-type convolution operator
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作者 H.M.Srivastava Sheza M.El-Deeb 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第2期443-457,共15页
By using a certain hybrid-type convolution operator,we first introduce a new subclass of normalized analytic functions in the open unit disk.For members of this analytic function class,we then derive several propertie... By using a certain hybrid-type convolution operator,we first introduce a new subclass of normalized analytic functions in the open unit disk.For members of this analytic function class,we then derive several properties and characteristics including(for example)the modified Hadamard products,Holder's inequalities and convolution properties as well as some closure properties under a general family of integral transforms. 展开更多
关键词 analytic functions univalent functions binomial series:hybrid-type convolution operator Holder's inequalities modi ed Hadamard product convolution properties closure properties under integral transforms
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Clinical observation on prognosis of mixed hemorrhoids treated with polidocanol injection combined with automatic elastic thread ligation operation 被引量:3
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作者 Yan-Mei Huang Dong Ouyang 《World Journal of Gastrointestinal Surgery》 2025年第1期209-216,共8页
BACKGROUND A total of 100 patients diagnosed with mixed hemorrhoids from October 2022 to September 2023 in our hospital were randomly divided into groups by dice rolling and compared with the efficacy of different tre... BACKGROUND A total of 100 patients diagnosed with mixed hemorrhoids from October 2022 to September 2023 in our hospital were randomly divided into groups by dice rolling and compared with the efficacy of different treatment options.AIM To analyze the clinical effect and prognosis of mixed hemorrhoids treated with polidocanol injection combined with automatic elastic thread ligation operation(RPH).METHODS A total of 100 patients with mixed hemorrhoids who visited our hospital from October 2022 to September 2023 were selected and randomly divided into the control group(n=50)and the treatment group(n=50)by rolling the dice.The procedure for prolapse and hemorrhoids(PPH)was adopted in the control group,while polidocanol foam injection+RPH was adopted in the treatment group.The therapeutic effects,operation time,wound healing time,hospital stay,pain situation(24 hours post-operative pain score,first defecation pain score),quality of life(QOL),incidence of complications(post-operative hemorrhage,edema,infection),incidence of anal stenosis 3 months post-operatively and recurrence rate 1 year post-operatively of the two groups were compared.RESULTS Compared with the control group,the total effective rate of treatment group was higher,and the difference was significant(P<0.05).The operation time/wound healing time/hospital stay in the treatment group were shorter than those in the control group(P<0.05).The pain scores at 24 hours after operation/first defecation pain score of the treatment group was significantly lower than those in the control group(P<0.05).After surgery,the QOL scores of the two groups decreased,with the treatment group having higher scores than that of the control group(P<0.05).Compared with the control group,the incidence of postoperative complications in the treatment group was lower,and the difference was significant(P<0.05);However,there was no significant difference in the incidence of postoperative bleeding between the two groups(P>0.05);There was no significant difference in the incidence of anal stenosis 3 months after operation and the recurrence rate 1 year after operation between the two groups(P>0.05).CONCLUSION For patients with mixed hemorrhoids,the therapeutic effect achieved by using polidocanol injection combined with RPH was better.The wounds of the patients healed faster,the postoperative pain was milder,QOL improved,and the incidence of complications was lower,and the short-term and long-term prognosis was good. 展开更多
关键词 Mixed hemorrhoids Polidocanol injection Automatic elastic thread ligation operation Postoperative hemorrhage The degree of pain Recurrent rate
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Technical development and future prospects of cooperative terminal guidance based on knowledge graph analysis:a review 被引量:2
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作者 Shuangxi LIU Zehuai LIN +1 位作者 Wei HUANG Binbin YAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第7期605-634,共30页
Cooperative guidance is a method for achieving combat objectives through information sharing and cooperative effects,and has emerged as a significant research area in the fields of missile guidance and systematic warf... Cooperative guidance is a method for achieving combat objectives through information sharing and cooperative effects,and has emerged as a significant research area in the fields of missile guidance and systematic warfare.This study presents a systematic review and analysis of current research on cooperative guidance.First,a bibliometric analysis is conducted on 513 articles using the Scopus database and CiteSpace software to assess keyword clustering,keyword cooccurrence,and keyword burst,and to later visualize the results.Second,fundamental theories of cooperative guidance,including relative motion modeling methods,algebraic graph theory,and multi-agent consensus theory,are summarized.Subsequently,an overview of current cooperative laws and corresponding analysis methods is provided,with categorization based on the cooperative structure and convergence performance.Finally,we summarize current research developments based on five perspectives and propose a developmental framework based on five layers(cyber,physical,decision,information,and system),discussing potential future advancements in cooperative terminal guidance.This framework emphasizes five key areas of research:networked,heterogeneous,integrated,intelligent,and group cooperations,with the goal of offering trends and insights for futurework. 展开更多
关键词 Cooperative guidance Guidance law Multiple missiles Cooperative operations Guidance and control Impact time control Impact angle control Consensus theory CiteSpace analysis
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2-complex Symmetric Weighted Composition Operators on Fock Space of C^(N)
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作者 JIANG Zhijie 《数学进展》 北大核心 2025年第1期37-49,共13页
The aim of the present paper is to study 2-complex symmetric bounded weighted composition operators on the Fock space of C^(N) with the conjugations J and J_(t,A,b) defined by ■ respectively,where k(z_(1),...,z_N)=(... The aim of the present paper is to study 2-complex symmetric bounded weighted composition operators on the Fock space of C^(N) with the conjugations J and J_(t,A,b) defined by ■ respectively,where k(z_(1),...,z_N)=(■,...,■),t∈C,b∈C^(N) and A is a linear operator on C^(N).An example of 2-complex symmetric bounded weighted composition operator with the conjugation J_(t,A,b) is given. 展开更多
关键词 Fock space weighted composition operator 2-complex symmetric operator reproducing kernel function
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Minimum Parametrization of the Cauchy Stress Operator 被引量:2
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作者 J.-F. Pommaret 《Journal of Modern Physics》 2021年第4期453-482,共30页
When D: <span style="white-space:nowrap;"><span style="white-space:nowrap;"><em><span style="white-space:nowrap;"><span style="white-space:nowrap;">... When D: <span style="white-space:nowrap;"><span style="white-space:nowrap;"><em><span style="white-space:nowrap;"><span style="white-space:nowrap;">&xi;</span></span></em><span style="white-space:nowrap;"><span style="white-space:nowrap;">&rarr;</span></span><em><span style="white-space:nowrap;"><span style="white-space:nowrap;">&eta;</span></span></em><em><span style="white-space:nowrap;"></span></em><em></em></span> </span>is a linear differential operator, a “direct problem” is to find the generating compatibility conditions (CC) in the form of an operator D<sub>1</sub>: <span style="white-space:nowrap;"><span style="white-space:nowrap;"><em><span style="white-space:nowrap;"><span style="white-space:nowrap;">&eta;</span></span></em><span style="white-space:nowrap;"><span style="white-space:nowrap;">&rarr;</span></span><em><span style="white-space:nowrap;"><span style="white-space:nowrap;">&xi;</span> </span></em></span></span>such that <span style="white-space:nowrap;">D<span style="white-space:nowrap;"><em><span style="white-space:nowrap;"><span style="white-space:nowrap;">&xi;</span></span></em></span>=<span style="white-space:nowrap;"><em><span style="white-space:nowrap;"><span style="white-space:nowrap;">&eta;</span></span></em></span></span> implies <span style="white-space:nowrap;">D<sub>1</sub><span style="white-space:nowrap;"><em><span style="white-space:nowrap;"><span style="white-space:nowrap;">&eta;</span></span></em></span>=0</span>. When D is involutive, the procedure provides successive first order involutive operators D1, ..., D<sub>n</sub>, when the ground manifold has dimension <em>n</em>, a result first found by M. Janet as early as in 1920, in a footnote. However, the link between this “Janet sequence” and the “Spencer sequence” first found by the author of this paper in 1978 is still not acknowledged. Conversely, when D<sub>1</sub> is given, a more difficult “inverse problem” is to look for an operator D: <span style="white-space:nowrap;"><span style="white-space:nowrap;"><em><em><span style="white-space:nowrap;">&xi;</span></em></em><span style="white-space:nowrap;">&rarr;</span><em><em><span style="white-space:nowrap;">&eta;</span></em><em></em><em></em> </em><em></em></span> </span>having the generating CC <span style="white-space:nowrap;">D<sub>1</sub><span style="white-space:nowrap;"><em><span style="white-space:nowrap;"><span style="white-space:nowrap;">&eta;</span></span></em></span><em></em>=0</span>. If this is possible, that is when the differential module defined by D<sub>1</sub> is torsion-free, one shall say that the operator D<sub>1</sub> is parametrized by D and there is no relation in general between D and D<sub>2</sub>. The parametrization is said to be “minimum” if the differential module defined by D has a vanishing differential rank and is thus a torsion module. The solution of this problem, first found by the author of this paper in 1995, is still not acknowledged. As for the applications of the “differential double duality” theory to standard equations of physics (<em>Cauchy</em> and Maxwell equations can be parametrized while <em>Einstein</em> equations cannot), we do not know other references. When <span style="font-size:10.0pt;font-family:;" "="">erator in arbitrary dimension</span>=1 as in control theory, the fact that controllability is a “built in” property of a control system, amounting to the existence of a parametrization and thus not depending on the choice of inputs and outputs, even with variable coefficients, is still not acknowledged by engineers. The parametrization of the <em>Cauchy</em> stress operator in arbitrary dimension <em>n</em> has nevertheless attracted, “separately” and without any general “guiding line”, many famous scientists (G.B. Airy in 1863 for <em>n </em>= 2, J.C. Maxwell in 1863, G. Morera and E. Beltrami in 1892 for <em style="white-space:normal;">n </em><span style="white-space:normal;">= 3</span> , A. Einstein in 1915 for <em style="white-space:normal;">n </em><span style="white-space:normal;">= 4</span> ). The aim of this paper is to solve the minimum parametrization problem in arbitrary dimension and to apply it through effective methods that could even be achieved by using computer algebra. Meanwhile, we prove that all these works are using the <em>Einstein</em> operator which is self-adjoint and not the <em>Ricci</em> operator, a fact showing that the <em>Einstein</em> operator, which cannot be parametrized, has already been exhibited by Beltrami more than 20 years before <em>Einstein</em>. As a byproduct, they are all based on the same confusion between the so-called <em>div</em> operator induced from the <em>Bianchi </em>operator D<sub>2</sub> and the <em>Cauchy</em> operator which is the formal adjoint of the Killing operator D parametrizing the Riemann operator D<sub>1</sub> for an arbitrary <em>n</em>. We prove that this purely mathematical result deeply questions the origin and existence of gravitational waves. We also present the similar motivating situation met in the study of contact structures when <em>n</em> = 3. Like the Michelson and Morley experiment, it is thus an open historical problem to know whether <em>Einstein</em> was aware of these previous works or not, but the comparison needs no comment. 展开更多
关键词 Differential operator Differential Sequence Killing operator Riemann operator Bianchi operator Cauchy operator Electromagnetism Elasticity General Relativity Gravitational Waves
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COMPACT LINEAR COMBINATIONS OF COMPOSITION OPERATORS ON THE UNIT BALL
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作者 Chunyu DONG Xin GUO Qijian KANG 《Acta Mathematica Scientia》 2025年第3期809-824,共16页
Recently,Choe-Koo-Wang(J Funct Anal,2020,278)demonstrated the rigid phenomenon:The compact linear combination of composition operators under the Coefficient Non-cancellation Condition(CNC),implies that each difference... Recently,Choe-Koo-Wang(J Funct Anal,2020,278)demonstrated the rigid phenomenon:The compact linear combination of composition operators under the Coefficient Non-cancellation Condition(CNC),implies that each difference is compact on the weighted Bergman space in the unit disk.Motivated by the subtle connection of composition operator theory on the weighted Bergman spaces,Korenblum spaces and bounded holomorphic function spaces,we first explore the rigid phenomenon which also holds on the Korenblum space over the unit ball.Furthermore,we discuss which difference of composition operators is compact when the compact combination of composition operators does not satisfy the condition(CNC)on Korenblum spaces and bounded holomorphic function spaces over the unit ball setting. 展开更多
关键词 composition operator linear combination compact operator weighted Bergman space Korenblum space
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ASYMPTOTIC PROPERTIES OF THE INTEGRATED DENSITY OF STATES FOR RANDOM SCHRÖDINGER OPERATORS
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作者 Longteng ZHANG Jin CHEN 《Acta Mathematica Scientia》 2025年第5期2251-2263,共13页
Explicit asymptotic properties of the integrated density of states N(λ)with respect to the spectrum for the random Schrödinger operator H^(ω)=(-△)^(α/2)+V^(ω)are established,whereα∈(0,2]and V^(ω)(X)=∑_(I... Explicit asymptotic properties of the integrated density of states N(λ)with respect to the spectrum for the random Schrödinger operator H^(ω)=(-△)^(α/2)+V^(ω)are established,whereα∈(0,2]and V^(ω)(X)=∑_(I∈Z^(d))ξ(i)(ω)W(x-i)is a random potential term generated by a sequence of independent and identically distributed random variables{ξ(i)}_(i)∈Z^(d)and a non-negative measurable function W(x).In particular,the exact order of asymptotic properties of N(λ)depends on the decay properties of the reference function W(x)and the spectrum properties of the first Dirichlet eigenvalue of(-△)^(α/2). 展开更多
关键词 ntegrated density of states random Schrodinger operator fractional Laplace operator potential Dirichlet eigenvalue
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Recognition of carrier-based aircraft flight deck operations based on dynamic graph
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作者 Xingyu GUO Jiaxin LI +3 位作者 Hua WANG Junnan LIU Yafei LI Mingliang XU 《Chinese Journal of Aeronautics》 2025年第3期474-490,共17页
Accurate recognition of flight deck operations for carrier-based aircraft, based on operation trajectories, is critical for optimizing carrier-based aircraft performance. This recognition involves understanding short-... Accurate recognition of flight deck operations for carrier-based aircraft, based on operation trajectories, is critical for optimizing carrier-based aircraft performance. This recognition involves understanding short-term and long-term spatial collaborative relationships among support agents and positions from long spatial–temporal trajectories. While the existing methods excel at recognizing collaborative behaviors from short trajectories, they often struggle with long spatial–temporal trajectories. To address this challenge, this paper introduces a dynamic graph method to enhance flight deck operation recognition. First, spatial–temporal collaborative relationships are modeled as a dynamic graph. Second, a discretized and compressed method is proposed to assign values to the states of this dynamic graph. To extract features that represent diverse collaborative relationships among agents and account for the duration of these relationships, a biased random walk is then conducted. Subsequently, the Swin Transformer is employed to comprehend spatial–temporal collaborative relationships, and a fully connected layer is applied to deck operation recognition. Finally, to address the scarcity of real datasets, a simulation pipeline is introduced to generate deck operations in virtual flight deck scenarios. Experimental results on the simulation dataset demonstrate the superior performance of the proposed method. 展开更多
关键词 Carrier-based aircraft Flight deck operation operation recognition Long spatial-temporal trajectories Dynamic graph Biased random walk Graph embeddings
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