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The character of Thurston's circle packings

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Science China Mathematics 2024年第7期67卷 1623-1640页

作者： Huabin ge Aijin Lin School of Mathematics Renmin University of ChinaBeijing100872China Department of Mathematics National University of Defense TechnologyChangsha410073China

We introduce the character of Thurston's circle packings in the hyperbolic background ***, some quite simple criteria are obtained for the existence of hyperbolic circle packings. For example,if a closed surface X admits a circle packing with all the vertex degrees d_(i)≥7, then it admits a unique complete hyperbolic metric so that the triangulation graph of the circle packing is isotopic to a geometric decomposition of X. This criterion is sharp due to the fact that any closed hyperbolic surface admits no triangulations with all d_(i)≤6. As a corollary, we obtain a new proof of the uniformization theorem for closed surfaces with genus g≥2;moreover, any hyperbolic closed surface has a geometric decomposition. To obtain our results, we use Chow-Luo's combinatorial Ricci flow as a fundamental tool.

关键词： character circle packings combinatorial Ricci flow

Family resilience of cancer patients:a concept analysis

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Frontiers of Nursing 2024年第2期11卷 153-158页

作者： ge-ge Han Department of Neurosurgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan 450001China

Objective:The concept of family resilience of cancer patients was discussed through literature review,which provided reference for nursing of cancer ***:China National Knowledge Infrastructure(CNKI),Wanfang Database,SinoMed,PubMed,Web of Science,and Embase were systematically searched,and the concept analysis method proposed by Walker and Avant was ***:In this study,we defined the concept of family resilience,identified attributes,and analyzed the antecedents and *** proposed operational definition of family resilience was:After a family member is diagnosed with cancer,the whole family can actively explore its own unique internal and external resources and advantages,strengthen self-regulation,jointly cope with the crisis by establishing close family relationships,providing mutual support to family members,and interacting with the outside ***:The definition of family resilience of cancer patients is conducive to the development of measurement tools and the improvement of family outcomes of adult cancer patients by intervening family resilience factors.

关键词： cancer patients concept analysis family resilience literature review nursing care

Essential Players in Cooperative Games with Graph Communication Structure

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Journal of the Operations Research Society of China 2024年第1期12卷 93-108页

作者： Guang Zhang Jing-Yi ge Business School University of Shanghai for Science and TechnologyShanghai200093China

A class of cooperative games with graph communication structure is studied in this paper by considering some important players,namely essential *** the assumption that only connected coalitions containing essential players are able to cooperate and obtain their worths,the class of graph games with essential players is proposed as well as an allocation *** proposed value follows the spirit of the Myerson value defined by applying the Shapley value on a modified *** properties,feasible component efficiency,the inessential component property,and fairness,are provided to fully characterize this value,where feasible component efficiency and fairness follows the same ideas of component efficiency and fairness for classical graph games,and the inessential component property says that the total payoffs of the players in a non-feasible component is ***,some computational aspects of the proposed value and comparisons with disjunctive permission value for games with permission structure are also studied,respectively.

关键词： Cooperative game Graph structure Essential player Myerson value Computation Permission structure

Constraint Learning-based Optimal Power Dispatch for Active Distribution Networks with Extremely Imbalanced Data

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 51-65页

作者： Yonghua Song ge Chen Hongcai Zhang State Key Laboratory of Internet of Things for Smart City and Department of Electrical and Computer Engineering University of MacaoMacao 999078China School of Electrical and Computer Engineering Purdue UniversityWest LafayetteIN 47907 USA

Transition towards carbon-neutral power systems has necessitated optimization of power dispatch in active distribution networks(ADNs)to facilitate integration of distributed renewable *** to unavailability of network topology and line impedance in many distribution networks,physical model-based methods may not be applicable to their *** tackle this challenge,some studies have proposed constraint learning,which replicates physical models by training a neural network to evaluate feasibility of a decision(i.e.,whether a decision satisfies all critical constraints or not).To ensure accuracy of this trained neural network,training set should contain sufficient feasible and infeasible ***,since ADNs are mostly operated in a normal status,only very few historical samples are ***,the historical dataset is highly imbalanced,which poses a significant obstacle to neural network *** address this issue,we propose an enhanced constraint learning ***,it leverages constraint learning to train a neural network as surrogate of ADN's ***,it introduces Synthetic Minority Oversampling Technique to generate infeasible samples to mitigate imbalance of historical *** incorporating historical and synthetic samples into the training set,we can significantly improve accuracy of neural ***,we establish a trust region to constrain and thereafter enhance reliability of the *** confirm the benefits of the proposed method in achieving desirable optimality and feasibility while maintaining low computational complexity.

关键词： Deep learning demand response distribution networks imbalanced data optimal power flow

STABLE RECOVERY OF SPARSELY CORRUPTED SIGNALS THROUGH JUSTICE PURSUIT DE-NOISING

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Journal of Computational Mathematics 2024年第1期42卷 271-288页

作者： Ningning Li Wengu Chen Huanmin ge Institute of Applied Physics and Computational Mathematics Beijing 100088China Beijing Sport University Beijing 100084China

This paper considers a corrupted compressed sensing problem and is devoted to recover signals that are approximately sparse in some general dictionary but corrupted by a combination of interference having a sparse representation in a second general dictionary and measurement *** provide new restricted isometry property(RIP)analysis to achieve stable recovery of sparsely corrupted signals through Justice Pursuit De-Noising(JPDN)with an additional *** main tool is to adapt a crucial sparse decomposition technique to the analysis of the Justice Pursuit *** proposed RIP condition improves the existing representative *** simulations are provided to verify the reliability of the JPDN model.

关键词： Justice Pursuit De-Noising Restricted isometry property Corrupted compressed sensing Signal recovery

Machine learning with active pharmaceutical ingredient/polymer interaction mechanism:Prediction for complex phase behaviors of pharmaceuticals and formulations

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Chinese Journal of Chemical Engineering 2024年第2期66卷 263-272页

作者： Kai ge Yiping Huang Yuanhui Ji Jiangsu Province Hi-Tech Key Laboratory for Biomedical Research School of Chemistry and Chemical EngineeringSoutheast UniversityNanjing 211189China

The high throughput prediction of the thermodynamic phase behavior of active pharmaceutical ingredients(APIs)with pharmaceutically relevant excipients remains a major scientific challenge in the screening of pharmaceutical *** this work,a developed machine-learning model efficiently predicts the solubility of APIs in polymers by learning the phase equilibrium principle and using a few molecular *** the few-shot learning framework,thermodynamic theory(perturbed-chain statistical associating fluid theory)was used for data augmentation,and computational chemistry was applied for molecular descriptors'*** results showed that the developed machine-learning model can predict the API-polymer phase diagram accurately,broaden the solubility data of APIs in polymers,and reproduce the relationship between API solubility and the interaction mechanisms between API and polymer successfully,which provided efficient guidance for the development of pharmaceutical formulations.

关键词： Multi-task machine learning Density functional theory Hydrogen bond interaction Miscibility Solubility

MULTIRATE TIME ITERATIVE SCHEME WITH MULTIPHYSICS FINITE ELEMENT METHOD FOR A NONLINEAR POROELASTICITY

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Journal of Computational Mathematics 2024年第2期42卷 597-616页

作者： Zhihao ge Hairun Li Tingting Li School of Mathematics and Statistics Henan UniversityKaifengHenan 475004China

In this paper,a multirate time iterative scheme with multiphysics finite element method is proposed and analyzed for the nonlinear poroelasticity *** original problem is reformulated into a generalized nonlinear Stokes problem coupled with a diffusion problem of a pseudo pressure field by a new multiphysics approach.A multiphysics finite element method is adopted for the spatial discretization,and the generalized nonlinear Stokes problem is solved in a coarse time step and the diffusion problem is solved in a finer time *** proposed algorithm is a decoupled algorithm,which is easily implemented in computation and reduces greatly computation *** stability analysis and the convergence analysis for the multirate iterative scheme with multiphysics finite element method are *** numerical tests are shown to demonstrate and validate the analysis results.

关键词： Nonlinear poroelasticity model Multiphysics finite element method Multirate iterative scheme

Establishment of a three-dimensional particle library for graded crushed stone based on a new aggregate morphology characterization method

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 117-130页

作者： Haitao ge Aimin Sha Zhenqiang Han School of Future Transportation Chang'an UniversityXi'an 710064China University of Strasbourg INSA StrasbourgCNRSICubeUMR 7357Strasbourg F-67000France School of Highway Chang'an UniversityXi'an 710064China Key Laboratory for Special Area Highway Engineering of Ministry of Education Chang'an UniversityXi'an 710064China

The morphology of graded crushed stone(GCS)particles has an essential influence on the performance of aggregate *** impact of particle shape is a comprehensive effect that cannot be considered separately,leading to difficulties in establishing the relationship between the mixture properties and the aggregate morphology by using laboratory *** discrete element method(DEM)is an effective way widely adopted to reconstruct the morphology of particles and simulate performance tests of granular ***,selecting limited particles characterizing a real particle-assembly for simulation is still a challenge in current research due to the inherent rich variability of particle *** this study,based on the acquisition of three-dimensional(3D)aggregate shapes by using laser scanning,ellipsoid index(EDI)translating the particle shape as a function of surface area,volume,and contour length is proposed to comprehensively evaluate aggregate ***,a particle library capable of characterizing aggregate morphology distribution is established based on the statistics of the corresponding morphological characteristics of particle *** model reliability is validated by carrying out a series of experimental and numerical penetration tests with nine different *** established particle library can be used to model aggregate mixtures and the proposed simulation framework is promising for optimizing the mixture gradation design numerically.

关键词： Particle library Discrete element method 3D laser scanning Coarse aggregate Morphology characterization Gradation design

Numerical Simulation of the Settling Flux of Biodeposition in a Bay with Cage Culture Through Similarity Theory and a Simplified Pollution Source

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Journal of Ocean University of China 2024年第1期23卷 247-254页

作者： LIU Yao CHEN Yifan ge Changzi Marine College Shandong UniversityWeihai 264209China

The settling flux of biodeposition affects the environmental quality of cage culture areas and determines their environmental carrying *** and effective simulation of the settling flux of biodeposition is extremely important for determining the spatial distribution of ***,biodeposition in cage culture areas without specific emission rules can be simplified as point source *** is a fluid simulation software that can simulate the dispersion of particulate matter simply and *** on the simplification of pollution sources and bays,the settling flux of biodeposition can be easily and effectively simulated by Fluent fluid *** the present work,the feasibility of this method was evaluated by simulation of the settling flux of biodeposition in Maniao Bay,Hainan Province,China,and 20 sampling sites were selected for determining the settling *** sampling sites P1,P2,P3,P4,P5,Z1,Z2,Z3,Z4,A1,A2,A3,A4,B1,B2,C1,C2,C3 and C4,the measured settling fluxes of biodeposition were 26.02,15.78,10.77,58.16,6.57,72.17,12.37,12.11,106.64,150.96,22.59,11.41,18.03,7.90,19.23,7.06,11.84,5.19 and 2.57 g d^(−1)m^(−2),*** simulated settling fluxes of biodeposition at the corresponding sites were 16.03,23.98,8.87,46.90,4.52,104.77,16.03,8.35,180.83,213.06,39.10,17.47,20.98,9.78,23.25,7.84,15.90,6.06 and 1.65 g d^(−1)m^(−2),*** was a positive correlation between the simulated settling fluxes and measured ones(R=0.94,P=2.22×10^(−9)<0.05),which implies that the spatial differentiation of biodeposition flux was well ***,the posterior difference ratio of the simulation was 0.38,and the small error probability was 0.94,which means that the simulated results reached an acceptable level from the perspective of relative ***,if nonpoint source pollution is simplified to point source pollution and open waters are simplified based on similarity theory,the setting flux of biodeposition i

关键词： fluent fluid simulation software pollution source simplification posterior difference ratio similarity theory Spear-man correlation