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Dimension.xpand.plus与日立7600生化分析仪检测结果的可比性研究 被引量:2
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作者 曾宇娟 黄子初 +1 位作者 刘光金 陈苑芬 《国际检验医学杂志》 CAS 2013年第20期2754-2755,共2页
目的探讨美国西门子Dimension.xpand.plus自动生化分析仪与日立7600自动生化仪检测结果之间是否具有可比性。方法按照EP9-A文件的要求选取实验标本,将Dimension.xpand.plus自动生化分析仪作为比对仪器,日立7600作为参考仪器,观察二者之... 目的探讨美国西门子Dimension.xpand.plus自动生化分析仪与日立7600自动生化仪检测结果之间是否具有可比性。方法按照EP9-A文件的要求选取实验标本,将Dimension.xpand.plus自动生化分析仪作为比对仪器,日立7600作为参考仪器,观察二者之间在尿素(Urea)、血清总蛋白(TP)、天门冬氨酸氨基转移酶(AST)和血糖(GLU)等4个检测项目上面的检测结果,并使用SPSS 13.0软件对之进行计算、分析,得出相关系数(r)和回归方程Y=bX+a。结果日立7600检测Urea、TP、AST和GLU的结果分别为(12.2±6.1)mmol/L、(46.58±12)mmol/L、(144.9±70.8)U/L、(16.9±8.5)mmol/L;Dimension.xpand.plus检测Urea、TP、AST和GLU的结果分别为(12.1±6.2)mmol/L、(47.62±12)mmol/L、(145.1±71.1)U/L、(17.1±8.6)mmol/L。2台生化仪检测结果比较差异无统计学意义(P>0.05)。结论 Dimension.xpand.plus与日立7600全自动生化仪检测结果具有可比性,在临床上具有相同的效果。 展开更多
关键词 dimension xpand PLUS 日立7600生化分析仪 比对试验 可比性
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A Note on Sufficient Dimension Folding for Regression Mean Function with Categorical Predictors
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作者 ZENG Bilin ADEKPEDJOU Akim WEN Xuerong Meggie 《Journal of Systems Science & Complexity》 2026年第1期158-179,共22页
Multi-dimensional arrays are referred to as tensors.Tensor-valued predictors are commonly encountered in modern biomedical applications,such as electroencephalogram(EEG),magnetic resonance imaging(MRI),functional MRI(... Multi-dimensional arrays are referred to as tensors.Tensor-valued predictors are commonly encountered in modern biomedical applications,such as electroencephalogram(EEG),magnetic resonance imaging(MRI),functional MRI(fMRI),diffusion-weighted MRI,and longitudinal health data.In survival analysis,it is both important and challenging to integrate clinically relevant information,such as gender,age,and disease state along with medical imaging tensor data or longitudinal health data to predict disease outcomes.Most existing higher-order sufficient dimension reduction regressions for matrix-or array-valued data focus solely on tensor data,often neglecting established clinical covariates that are readily available and known to have predictive value.Based on the idea of Folded-Minimum Average Variance Estimation(Folded-MAVE:Xue and Yin,2014),the authors propose a new method,Partial Dimension Folded-MAVE(PF-MAVE),to address regression mean functions with tensor-valued covariates while simultaneously incorporating clinical covariates,which are typically categorical variables.Theorems and simulation studies demonstrate the importance of incorporating these categorical clinical predictors.A survival analysis of a longitudinal study of primary biliary cirrhosis(PBC)data is included for illustration of the proposed method. 展开更多
关键词 Mean dimension folding subspace minimum average variance estimation sufficient dimension folding subspace survival analysis tensor data
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Special Issue“Recent Developments in Dimension Reduction and Model Checking”——In Honor of Professor Lixing Zhu's Outstanding Contributions in Statistics
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作者 ZHU Liping XU Wangli LI Yingxing 《Journal of Systems Science & Complexity》 2026年第1期1-2,共2页
The proliferation of high-dimensional data and the widespread use of complex models present central challenges in contemporary statistics and data science.Dimension reduction and model checking,as two foundational pil... The proliferation of high-dimensional data and the widespread use of complex models present central challenges in contemporary statistics and data science.Dimension reduction and model checking,as two foundational pillars supporting scientific inference and data-driven decisionmaking,have evolved through the collective wisdom of generations of statisticians.This special issue,titled"Recent Developments in Dimension Reduction and Model Checking for regressions",not only aims to showcase cutting-edge advances in the field but also carries a distinct sense of academic homage to honor the groundbreaking and enduring contributions of Professor Lixing Zhu,a leading scholar whose work has profoundly shaped both areas. 展开更多
关键词 scientific inference model checking model checkingas complex models dimension reduction high dimensional data
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Envelope Inverse Regression for Dimension Reduction:A Review and New Perspectives
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作者 ZENG Jing WANG Ning ZHANG Xin 《Journal of Systems Science & Complexity》 2026年第1期284-308,共25页
In this note,the authors revisit the envelope dimension reduction,which was first introduced for estimating a sufficient dimension reduction subspace without inverting the sample covariance.Motivated by the recent dev... In this note,the authors revisit the envelope dimension reduction,which was first introduced for estimating a sufficient dimension reduction subspace without inverting the sample covariance.Motivated by the recent developments in envelope methods and algorithms,the authors refresh the envelope inverse regression as a flexible alternative to the existing inverse regression methods in dimension reduction.The authors discuss the versatility of the envelope approach and demonstrate the advantages of the envelope dimension reduction through simulation studies. 展开更多
关键词 dimension selection envelope model subspace estimation sufficient dimension reduction
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Cooperative Metaheuristics with Dynamic Dimension Reduction for High-Dimensional Optimization Problems
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作者 Junxiang Li Zhipeng Dong +2 位作者 Ben Han Jianqiao Chen Xinxin Zhang 《Computers, Materials & Continua》 2026年第1期1484-1502,共19页
Owing to their global search capabilities and gradient-free operation,metaheuristic algorithms are widely applied to a wide range of optimization problems.However,their computational demands become prohibitive when ta... Owing to their global search capabilities and gradient-free operation,metaheuristic algorithms are widely applied to a wide range of optimization problems.However,their computational demands become prohibitive when tackling high-dimensional optimization challenges.To effectively address these challenges,this study introduces cooperative metaheuristics integrating dynamic dimension reduction(DR).Building upon particle swarm optimization(PSO)and differential evolution(DE),the proposed cooperative methods C-PSO and C-DE are developed.In the proposed methods,the modified principal components analysis(PCA)is utilized to reduce the dimension of design variables,thereby decreasing computational costs.The dynamic DR strategy implements periodic execution of modified PCA after a fixed number of iterations,resulting in the important dimensions being dynamically identified.Compared with the static one,the dynamic DR strategy can achieve precise identification of important dimensions,thereby enabling accelerated convergence toward optimal solutions.Furthermore,the influence of cumulative contribution rate thresholds on optimization problems with different dimensions is investigated.Metaheuristic algorithms(PSO,DE)and cooperative metaheuristics(C-PSO,C-DE)are examined by 15 benchmark functions and two engineering design problems(speed reducer and composite pressure vessel).Comparative results demonstrate that the cooperative methods achieve significantly superior performance compared to standard methods in both solution accuracy and computational efficiency.Compared to standard metaheuristic algorithms,cooperative metaheuristics achieve a reduction in computational cost of at least 40%.The cooperative metaheuristics can be effectively used to tackle both high-dimensional unconstrained and constrained optimization problems. 展开更多
关键词 dimension reduction modified principal components analysis high-dimensional optimization problems cooperative metaheuristics metaheuristic algorithms
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THE VARIATIONAL PRINCIPLE FOR A BS DIMENSION OF SUBSETS FOR NON-AUTONOMOUS DYNAMICAL SYSTEMS
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作者 Zhongxuan YANG Xiaojun HUANG 《Acta Mathematica Scientia》 2026年第1期311-329,共19页
In this manuscript,we consider a non-autonomous dynamical system.Using the Carathéodory structure,we define a BS dimension on an arbitrary subset and obtain a Bowen’s equation that illustrates the relation of th... In this manuscript,we consider a non-autonomous dynamical system.Using the Carathéodory structure,we define a BS dimension on an arbitrary subset and obtain a Bowen’s equation that illustrates the relation of the BS dimension to the Pesin-Pitskel topological pressure given by Nazarian[24].Moreover,we establish a variational principle and an inverse variational principle for the BS dimension of non-autonomous dynamical systems.Finally,we also get an analogue of Billingsley’s theorem for the BS dimension of non-autonomous dynamical systems. 展开更多
关键词 non-autonomous dynamical systems BS dimension Bowen’s equation variational principle
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Nonlinear Sufficient Dimension Reduction for Metric Space Objects
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作者 HUANG Xueyan LI Yunchen +1 位作者 YING Chao YU Zhou 《Journal of Systems Science & Complexity》 2026年第1期230-254,共25页
In this paper,the authors propose a nonlinear dimension reduction technique based on Fréchet inverse regression to achieve sufficient dimension reduction for responses in metric spaces and predictors in Riemannia... In this paper,the authors propose a nonlinear dimension reduction technique based on Fréchet inverse regression to achieve sufficient dimension reduction for responses in metric spaces and predictors in Riemannian manifolds.The authors rigorously establish statistical properties of the estimators,providing formal proofs of their consistency and asymptotic behaviors.The effectiveness of our method is demonstrated through extensive simulations and applications to real-world datasets which highlight its practical utility for complex data with non-Euclidean structures. 展开更多
关键词 Fréchet sufficient dimension reduction inverse regression metric space nonlinear model
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Envelope Dimension Reduction with Application to Binary Classification
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作者 SOALE Abdul-Nasah DONG Yuexiao 《Journal of Systems Science & Complexity》 2026年第1期79-87,共9页
Classical linear discriminant analysis(LDA)(Fisher,1936)implicitly assumes the classification boundary depends on only one linear combination of the predictors.This restriction can lead to poor classification in appli... Classical linear discriminant analysis(LDA)(Fisher,1936)implicitly assumes the classification boundary depends on only one linear combination of the predictors.This restriction can lead to poor classification in applications where the decision boundary depends on multiple linear combinations of the predictors.To overcome this challenge,the authors first project the predictors onto an envelope central space and then perform LDA based on the sufficient predictor.The performance of the proposed method in improving classification accuracy is demonstrated in both synthetic data and real applications. 展开更多
关键词 Envelope linear regression linear discriminant analysis sliced inverse regression sufficient dimension reduction
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On the Ding Injective Dimensions of Complexes
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作者 Chiyu LONG Sixin ZHAO Bo LU 《Journal of Mathematical Research with Applications》 2026年第2期175-196,共22页
In this paper,we study two types of the Ding injective dimensions of complexes.First,we provide some equivalent characterizations of the dimension related to the special Ding injec-tive preenvelopes.Furthermore,we con... In this paper,we study two types of the Ding injective dimensions of complexes.First,we provide some equivalent characterizations of the dimension related to the special Ding injec-tive preenvelopes.Furthermore,we consider the relationship between the dimensions Dipd(Y)and Did(Y)of the complex Y,where Dipd(Y)denotes the dimension associated with special Ding injective preenvelopes,and Did(Y)denotes the dimension associated with DG-injective resolutions.It is demonstrated that Dipd(Y)=Did(Y)for any bounded complex Y. 展开更多
关键词 Ding injective dimension special Ding injective preenvelope relative cohomology group
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Exponential Synchronization of Infinite-Dimensional Stochastic Systems With Poisson Jumps Under Aperiodically Intermittent Impulse Control
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作者 Lili Chen Yiqun Liu +1 位作者 Yanfeng Zhao Zhen Wang 《IEEE/CAA Journal of Automatica Sinica》 2026年第2期383-393,共11页
A novel aperiodically intermittent impulse control(AIIC)method is proposed to investigate the exponential synchronization in mean square(ESMS)of a class of impulsive stochastic infinite-dimensional systems with Poisso... A novel aperiodically intermittent impulse control(AIIC)method is proposed to investigate the exponential synchronization in mean square(ESMS)of a class of impulsive stochastic infinite-dimensional systems with Poisson jumps(ISIDSP).The AIIC control strategy inherits the flexibility of aperiodically intermittent control,including the variable control period,adjustable control interval length,and the discretization of impulsive control.In addition,this article introduces a novel mild Itô's formula.By leveraging semigroup theory,the contraction mapping principle,and graph theory,along with constructing the Lyapunov function,the criterion for the existence and uniqueness of a mild solution of ISIDSP is thereby established.Furthermore,the mean-square exponential synchronization problem of the above systems is resolved,and the constraints within the mild solution domain are alleviated.These criteria clarify the impact of control parameters,control intervals and network topology on ESMS.The theoretical results are subsequently applied to a class of neural networks with reaction-diffusion processes,and the validity of the results is verified using numerical simulations. 展开更多
关键词 Complex network exponential synchronization impulse control infinite dimensional system intermittent control
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Hydrogenation and Doping Induced One-Dimensional High-Temperature Superconductivity in carbon Nanotube
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作者 Hao Wang Bao-Tong Liu +5 位作者 Shu-Xiang Qiao Na Jiao Guili Yu Ping Zhang C.S.Ting Hong-Yan Lu 《Chinese Physics Letters》 2026年第1期198-210,共13页
In recent years,the research on superconductivity in one-dimensional(1D)materials has been attracting increasing attention due to its potential applications in low-dimensional nanodevices.However,the critical temperat... In recent years,the research on superconductivity in one-dimensional(1D)materials has been attracting increasing attention due to its potential applications in low-dimensional nanodevices.However,the critical temperature(T_(c))of 1D superconductors is low.In this work,we theoretically investigate the possible high T_(c) superconductivity of(5,5)carbon nanotube(CNT).The pristine(5,5)CNT is a Dirac semimetal and can be modulated into a semiconductor by full hydrogenation.Interestingly,by further hole doping,it can be regulated into a metallic state with the sp^(3)-hybridized σ electrons metalized,and a giant Kohn anomaly appears in the optical phonons.The two factors together enhance the electron–phonon coupling,and lead to high-T_(c) superconductivity.When the hole doping concentration of hydrogenated-(5,5)CNT is 2.5 hole/cell,the calculated T_(c) is 82.3 K,exceeding the boiling point of liquid nitrogen.Therefore,the predicted hole-doped hydrogenated-(5,5)CNT provides a new platform for 1D high-T_(c) superconductivity and may have potential applications in 1D nanodevices. 展开更多
关键词 high temperature superconductivity DOPING critical temperature dirac semimetal one dimensional materials HYDROGENATION full hydrogenationinterestinglyby hole dopingit
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CDA-Net:Cross dimensional attention network for wetland bird detection
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作者 Jia'nan Lv Changchun Zhang +1 位作者 Jiangjian Xie Junguo Zhang 《Avian Research》 2026年第1期216-227,共12页
Monitoring waterbirds is vital for evaluating the ecological health of wetlands,and object detection offers an automated solution for identifying birds in monitoring imagery.However,conventional detection methods ofte... Monitoring waterbirds is vital for evaluating the ecological health of wetlands,and object detection offers an automated solution for identifying birds in monitoring imagery.However,conventional detection methods often overlook the multi-scale nature of bird targets,limiting their ability to capture rich contextual information across different scales.To address this,we propose a cross-dimensional attention network(CDA-Net)for bird detection that integrates spatial and channel information to improve species recognition.The proposed CDA-Net partitions feature maps into multiple channel wise sub-features.Spatial and channel attention are applied to each subfeature,and the resulting features are fused using the Hadamard product.The fused features are then forwarded to the detection head to generate the final detection results.This approach effectively captures and integrates information across spatial and channel dimensions.Experiments on our self-constructed Nanhai Wetland Waterbird Dataset and the public CUB-200-2011 dataset yield precision scores of 91.32%and 81.99%,respectively,outperforming existing methods.Our approach effectively handles scale variation in bird detection and provides a valuable tool for advancing automated wetland waterbird monitoring. 展开更多
关键词 Bird detection Channel and spatial attention Cross dimensional network Feature integration Multi sizes object
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Erratum:Bone Regeneration Eff cacy and Applicability of Defect-Fitting 4D Scaffolds Based on Shape Conformity in Three-dimensional Curved Bone Defects
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作者 Min-Soo Ghim Se-Jin Jang +3 位作者 Eun-Yong Choi Meiling Quan Young-Yul Kim Young-Sam Cho 《Journal of Bionic Engineering》 2026年第1期550-550,共1页
The original online version of this article was revised:The layout update for Article 758 has impacted the page range in the published issue,but did not affect the scholarly content.To ensure consistency with the orig... The original online version of this article was revised:The layout update for Article 758 has impacted the page range in the published issue,but did not affect the scholarly content.To ensure consistency with the originally assigned pages(2595-2614),we will need to publish an erratum to correct the article and restore the original page range.The original article has been corrected. 展开更多
关键词 defect fitting D scaffolds layout update shape conformity three dimensional curved bone defects bone regeneration
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Three-dimensional patient-derived cell models represent an emerging frontier in the study of neurodegenerative diseases
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作者 Rachel J.Boyd Vasiliki Mahairaki 《Neural Regeneration Research》 2026年第6期2327-2328,共2页
Neurodegenerative disorders represent an increasingly pertinent public health crisis.As a greater proportion of the population ages,neurodegenerative disorders and other diseases of aging place undue burdens on patien... Neurodegenerative disorders represent an increasingly pertinent public health crisis.As a greater proportion of the population ages,neurodegenerative disorders and other diseases of aging place undue burdens on patients,caregivers,and healthcare workers.Alzheimer’s disease(AD)and Parkinson’s disease represent the two most common neurodegenerative disorders in the population,affecting over 65 million people,worldwide. 展开更多
关键词 Alzheimer s disease public health crisis neurodegenerative diseases neurodegenerative disorders parkinson s disease aging three dimensional patient derived cell models
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Enabling Intrinsic Antiferroelectricity in Two-dimensional NbOCl_(2):Molecular Dynamics Simulations based on Deep Learning Interatomic Potential
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作者 Jiawei Mao Yinglu Jia +2 位作者 Gaoyang Gou Shi Liu Xiao Cheng Zeng 《Chinese Physics Letters》 2026年第1期156-178,共23页
Compared to the well-studied two-dimensional(2D)ferroelectricity,the appearance of 2D antiferroelectricity is much rarer,where local dipoles from the nonequivalent sublattices within 2D monolayers are oppositely orien... Compared to the well-studied two-dimensional(2D)ferroelectricity,the appearance of 2D antiferroelectricity is much rarer,where local dipoles from the nonequivalent sublattices within 2D monolayers are oppositely oriented.Using NbOCl_(2) monolayer with competing ferroelectric(FE)and antiferroelectric(AFE)phases as a 2D material platform,we demonstrate the emergence of intrinsic antiferroelectricity in NbOCl_(2) monolayer under experimentally accessible shear strain,along with new functionality associated with electric field-induced AFE-to-FE phase transition.Specifically,the complex configuration space accommodating FE and AFE phases,polarization switching kinetics,and finite temperature thermodynamic properties of 2D NbOCl_(2) are all accurately predicted by large-scale molecular dynamics simulations based on deep learning interatomic potential model.Moreover,room temperature stable antiferroelectricity with low polarization switching barrier and one-dimensional collinear polarization arrangement is predicted in shear-deformed NbOCl_(2) monolayer.The transition from AFE to FE phase in 2D NbOCl_(2) can be triggered by a low critical electric field,leading to a double polarization–electric(P–E)loop with small hysteresis.A new type of optoelectronic device composed of AFE-NbOCl_(2) is proposed,enabling electric“writing”and nonlinear optical“reading”logical operation with fast operation speed and low power consumption. 展开更多
关键词 d monolayers local dipoles nonequivalent sublattices intrinsic antiferroelectricity two dimensional nbocl d antiferroelectricity experimentally accessible shear strainalong molecular dynamics simulations
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Single-Dimensional Encryption Against Stealthy Attacks on Stochastic Event-Based Estimation
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作者 Jun Shang Di Zhao +1 位作者 Hanwen Zhang Dawei Shi 《IEEE/CAA Journal of Automatica Sinica》 2026年第1期233-235,共3页
Dear Editor,This letter studies the problem of stealthy attacks targeting stochastic event-based estimation,alongside proposing measures for their mitigation.A general attack framework is introduced,and the correspond... Dear Editor,This letter studies the problem of stealthy attacks targeting stochastic event-based estimation,alongside proposing measures for their mitigation.A general attack framework is introduced,and the corresponding stealthiness condition is analyzed.To enhance system security,we advocate for a single-dimensional encryption method,showing that securing a singular data element is sufficient to shield the system from the perils of stealthy attacks. 展开更多
关键词 enhance system securitywe securing singular data element single dimensional encryption stochastic event based estimation stealthiness condition security mitigation attack framework stealthy attacks
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Managing Multidimensional International World With Spatial Grasp Model 被引量:1
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作者 Peter Simon Sapaty 《International Relations and Diplomacy》 2025年第5期257-269,共13页
“Multidimensional international world”refers to understanding the world through multiple dimensions beyond traditional economic or political measures,fostering cross-cultural collaboration,and creating systems that ... “Multidimensional international world”refers to understanding the world through multiple dimensions beyond traditional economic or political measures,fostering cross-cultural collaboration,and creating systems that balance global integration with local needs.This also includes management of global business operations across diverse cultures in a multipolar international landscape.The paper briefs the developed and already tested in numerous applications high-level Spatial Grasp Model and Technology(SGT),which can help investigate and manage complex systems with a holistic spatial approach effectively covering various physical and virtual dimensions,their interrelations,and integration as a whole.Different areas will be investigated with examples of practical solutions in them and their combinations in a high-level Spatial Grasp Language(SGL),the key element of SGT.This allows for the creation and distributed management of very large spatial networks with different orientation which can be self-spreading,self-analyzing,self-modifying,and self-recovering in complex terrestrial and celestial environments,and also organize dynamic multi-networking solutions supporting global evolution and integrity. 展开更多
关键词 multidimensional world Spatial Grasp Technology Spatial Grasp Language distributed network operations dimensions investigation and management collective spatial solutions global integrity
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The Institutional Dimension of Global Human Rights Governance--And on the Institutional Contributions of the Four Global Initiatives
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作者 MENG Qingtao LIU Yu 《The Journal of Human Rights》 2025年第6期1439-1449,共11页
At a time when global crises continue to intensify,UN Secretary-General António Guterres stated at this year’s high-level plenary meeting to commemorate the 80th anniversary of the establishment of the United Na... At a time when global crises continue to intensify,UN Secretary-General António Guterres stated at this year’s high-level plenary meeting to commemorate the 80th anniversary of the establishment of the United Nations that the core of the 2030 Agenda for Sustainable Development,the Pact for the Future,and the UN 80 Initiative lies in renewing the foundations of international cooperation. 展开更多
关键词 sustainable development institutional dimension AGENDA renewing foundations international cooperation sustainable developmentthe global initiatives united nations un
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Influence of Fractal Dimension on Gas-Driven Two-Phase Flow in Fractal Porous Media:A VOF Model-Based Simulation
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作者 Xiaolin Wang Richeng Liu +3 位作者 Kai Qiu Zhongzhong Liu Shisen Zhao Shuchen Li 《Computer Modeling in Engineering & Sciences》 2025年第7期289-307,共19页
Gas-liquid two-phase flow in fractal porous media is pivotal for engineering applications,yet it remains challenging to be accurately characterized due to complex microstructure-flow interactions.This study establishe... Gas-liquid two-phase flow in fractal porous media is pivotal for engineering applications,yet it remains challenging to be accurately characterized due to complex microstructure-flow interactions.This study establishes a pore-scale numerical framework integratingMonte Carlo-generated fractal porousmedia with Volume of Fluid(VOF)simulations to unravel the coupling among pore distribution characterized by fractal dimension(Df),flow dynamics,and displacement efficiency.A pore-scale model based on the computed tomography(CT)microstructure of Berea sandstone is established,and the simulation results are compared with experimental data.Good agreement is found in phase distribution,breakthrough behavior,and flow path morphology,confirming the reliability of the numerical simulation method.Ten fractal porous media models with Df ranging from 1.25~1.7 were constructed using a Monte-Carlo approach.The gas-liquid two-phase flow dynamics was characterized using the VOF solver across gas injection rates of 0.05-5m/s,inwhich the time-resolved two-phase distribution patternswere systematically recorded.The results reveal that smaller fractal dimensions(Df=1.25~1.45)accelerate fingering breakthrough(peak velocity is 1.73 m/s at Df=1.45)due to a bimodal pore size distribution dominated by narrow channels.Increasing Df amplifies vorticity generation by about 3 times(eddy viscosity is 0.033 Pa⋅s at Df=1.7)through reduced interfacial curvature,while tortuosity-driven pressure differentials transition from sharp increases(0.4~6.3 Pa at Df=1.25~1.3)to inertial plateaus(4.8 Pa at Df=1.7).A nonlinear increase in equilibrium gas volume fraction(fav=0.692 at Df=1.7)emerges from residual gas saturation and turbulence-enhanced dispersion.This behavior is further modulated by flow velocity,with fav peaking at 0.72 under capillary-dominated conditions(0.05 m/s),but decreasing to 0.65 in the inertial regime(0.5 m/s).The work quantitatively links fractal topology to multiphase flow regimes,demonstrating the critical role of Df in governing preferential pathways,energy dissipation,and phase distribution. 展开更多
关键词 Fractal porous media gas-liquid two-phase flow fractal dimension vortex evolution VOF model displacement efficiency
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Research on Dimension Analysis of Spectative Buildings Based on Fractal Theory
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作者 Yunyang Zheng Jiayao Zhu +1 位作者 Jingjing Guo Hao Hu 《Journal of Architectural Research and Development》 2025年第4期71-76,共6页
Based on the fractal theory,this paper takes the form of performing architecture as the research object,and systematically discusses the application value of fractal dimension in architectural design.By expounding the... Based on the fractal theory,this paper takes the form of performing architecture as the research object,and systematically discusses the application value of fractal dimension in architectural design.By expounding the self-affine,self-similarity,and iterative generation characteristics of fractal geometry,the Box-Counting Dimension method is introduced as a quantitative tool to measure the dimensions of the roof plane,facade,and spatial shape of Wuzhen Grand Theatre and Harbin Grand Theatre.The research shows that the geometric complexity of Wuzhen Grand Theater in the“fifth façade”and multi-faceted façade is significantly higher than that of Harbin Grand Theater,and its morphological design is more inclined to echo the texture of the surrounding water towns.The Harbin Grand Theater realizes the dialogue with the natural environment with simple nonlinear lines.The research proves that fractal dimension can effectively quantify the complexity of architectural form,provide a scientific basis for the form design,environmental integration,and form interpretation of performance architecture,and expand the mathematical analysis dimension of architectural form design. 展开更多
关键词 Fractal dimension Fractal geometry Performing architecture Architectural form Architectural design
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