Noise-induced phase transition in the Vicsek model through eigen microstate methodology

This paper presents a comprehensive framework for analyzing phase transitions in collective models such as theVicsek model under various noise types. The Vicsek model, focusing on understanding the collective behaviors of socialanimals, is known due to its discontinuous phase transitions under vector noise. However, its behavior under scalar noiseremains less conclusive. Renowned for its efficacy in the analysis of complex systems under both equilibrium and nonequilibriumstates, the eigen microstate method is employed here for a quantitative examination of the phase transitions inthe Vicsek model under both vector and scalar noises. The study finds that the Vicsek model exhibits discontinuous phasetransitions regardless of noise type. Furthermore, the dichotomy method is utilized to identify the critical points for thesephase transitions. A significant finding is the observed increase in the critical point for discontinuous phase transitions withescalation of population density.

Exploring Motor Imagery EEG: Enhanced EEG Microstate Analysis with GMD-Driven Density Canopy Method

The analysis of microstates in EEG signals is a crucial technique for understanding the spatiotemporal dynamics of brain electrical activity.Traditional methods such as Atomic Agglomerative Hierarchical Clustering(AAHC),K-means clustering,Principal Component Analysis(PCA),and Independent Component Analysis(ICA)are limited by a fixed number of microstate maps and insufficient capability in cross-task feature extraction.Tackling these limitations,this study introduces a Global Map Dissimilarity(GMD)-driven density canopy K-means clustering algorithm.This innovative approach autonomously determines the optimal number of EEG microstate topographies and employs Gaussian kernel density estimation alongside the GMD index for dynamic modeling of EEG data.Utilizing this advanced algorithm,the study analyzes the Motor Imagery(MI)dataset from the GigaScience database,GigaDB.The findings reveal six distinct microstates during actual right-hand movement and five microstates across other task conditions,with microstate C showing superior performance in all task states.During imagined movement,microstate A was significantly enhanced.Comparison with existing algorithms indicates a significant improvement in clustering performance by the refined method,with an average Calinski-Harabasz Index(CHI)of 35517.29 and a Davis-Bouldin Index(DBI)average of 2.57.Furthermore,an information-theoretical analysis of the microstate sequences suggests that imagined movement exhibits higher complexity and disorder than actual movement.By utilizing the extracted microstate sequence parameters as features,the improved algorithm achieved a classification accuracy of 98.41%in EEG signal categorization for motor imagery.A performance of 78.183%accuracy was achieved in a four-class motor imagery task on the BCI-IV-2a dataset.These results demonstrate the potential of the advanced algorithm in microstate analysis,offering a more effective tool for a deeper understanding of the spatiotemporal features of EEG signals.

Abnormalities of electroencephalography microstates in patients with depression and their association with cognitive function

BACKGROUND A growing number of recent studies have explored underlying activity in the brain by measuring electroencephalography(EEG)in people with depression.However,the consistency of findings on EEG microstates in patients with depression is poor,and few studies have reported the relationship between EEG microstates,cognitive scales,and depression severity scales.AIM To investigate the EEG microstate characteristics of patients with depression and their association with cognitive functions.METHODS A total of 24 patients diagnosed with depression and 32 healthy controls were included in this study using the Structured Clinical Interview for Disease for The Diagnostic and Statistical Manual of Mental Disorders,Fifth Edition.We collected information relating to demographic and clinical characteristics,as well as data from the Repeatable Battery for the Assessment of Neuropsychological Status(RBANS;Chinese version)and EEG.RESULTS Compared with the controls,the duration,occurrence,and contribution of microstate C were significantly higher[depression(DEP):Duration 84.58±24.35,occurrence 3.72±0.56,contribution 30.39±8.59;CON:Duration 72.77±10.23,occurrence 3.41±0.36,contribution 24.46±4.66;Duration F=6.02,P=0.049;Occurrence F=6.19,P=0.049;Contribution F=10.82,P=0.011]while the duration,occurrence,and contribution of microstate D were significantly lower(DEP:Duration 70.00±15.92,occurrence 3.18±0.71,contribution 22.48±8.12;CON:Duration 85.46±10.23,occurrence 3.54±0.41,contribution 28.25±5.85;Duration F=19.18,P<0.001;Occurrence F=5.79,P=0.050;Contribution F=9.41,P=0.013)in patients with depression.A positive correlation was observed between the visuospatial/constructional scores of the RBANS scale and the transition probability of microstate class C to B(r=0.405,P=0.049).CONCLUSION EEG microstate,especially C and D,is a possible biomarker in depression.Patients with depression had a more frequent transition from microstate C to B,which may relate to more negative rumination and visual processing.

Macrostate and Microstate of EEG Spatio-Temporal Nonlinear Dynamics in Zen Meditation

Macrostate and microstate characteristics of interregional nonlinear interdependence of brain dynamics are investigated for Zen-meditation and normal resting EEG. Evaluation of nonlinear interdependence based on nonlinear dynamic theory and phase space reconstruction is employed in the 30-channel electroencephalographic (EEG) signals to characterize the functioning interactions among different local neuronal networks. This paper presents a new scheme for exploring the microstate and macrostate of interregional brain neural network interactivity. Nonlinear interdependence quantified by similarity index is applied to the phase trajectory reconstructed from multi-channel EEG. The microstate similarity-index matrix (miSIM) is evaluated every 5 millisecond. The miSIMs are classified by K-means clustering. The cluster center corresponds to the macrostate SIM (maSIM) evaluated by conventional scheme. Zen-meditation EEG exhibits rather stationary and stronger interconnectivity among frontal midline regional neural oscillators, whereas resting EEG appears to drift away more often from the midline and extend to the inferior brain regions.

Using Atomic Microstates and Atomic Number Parity in Support of Lutetium and Lawrencium Classification as Transition Metals

Unlike other groups of elements, Group 3 constituency remains unsettled. This article argues that ground level microstates and atomic number parity suggest Sc-Y-Lu-Lr Group 3 membership.

Eigen microstates and their evolutions in complex systems

Emergence refers to the existence or formation of collective behaviors in complex systems.Here,we develop a theoretical framework based on the eigen microstate theory to analyze the emerging phenomena and dynamic evolution of complex system.In this framework,the statistical ensemble composed of M microstates of a complex system with N agents is defined by the normalized N×M matrix A,whose columns represent microstates and order of row is consist with the time.The ensemble matrix A can be decomposed as■,where r=min(N,M),eigenvalueσIbehaves as the probability amplitude of the eigen microstate U_I so that■and U_I evolves following V_I.In a disorder complex system,there is no dominant eigenvalue and eigen microstate.When a probability amplitudeσIbecomes finite in the thermodynamic limit,there is a condensation of the eigen microstate UIin analogy to the Bose–Einstein condensation of Bose gases.This indicates the emergence of U_I and a phase transition in complex system.Our framework has been applied successfully to equilibrium threedimensional Ising model,climate system and stock markets.We anticipate that our eigen microstate method can be used to study non-equilibrium complex systems with unknown orderparameters,such as phase transitions of collective motion and tipping points in climate systems and ecosystems.

Condensation of eigen microstate in statistical ensemble and phase transition

In a statistical ensemble with M microstates, we introduce an M × M correlation matrix with correlations among microstates as its elements. Eigen microstates of ensemble can be defined using eigenvectors of the correlation matrix. The eigenvalue normalized by M represents weight factor in the ensemble of the corresponding eigen microstate. In the limit M →∞, weight factors drop to zero in the ensemble without localization of the microstate. The finite limit of the weight factor when M →∞ indicates a condensation of the corresponding eigen microstate. This finding indicates a transition into a new phase characterized by the condensed eigen microstate. We propose a finite-size scaling relation of weight factors near critical point, which can be used to identify the phase transition and its universality class of general complex systems. The condensation of eigen microstate and the finite-size scaling relation of weight factors are confirmed using Monte Carlo data of one-dimensional and two-dimensional Ising models.

Revealing the Local Microstates of Fe–Mn–Al Medium Entropy Alloy:A Comprehensive First-principles Study

Entropy-stabilized multi-component alloys have been considered to be prospective structural materials attributing to their impressive mechanical and functional properties.The local chemical complexions,microstates and configurational transformations are essential to reveal the structure–property relationship,thus,to promote the development of advanced multicomponent alloys.In the present work,effects of local lattice distortion(LLD)and microstates of various configurations on the equilibrium volume(V0),total energy,Fermi energy,magnetic moment(μMag)and electron work function(Φ)and bonding structures of the Fe–Mn–Al medium entropy alloy(MEA)have been investigated comprehensively by first-principles calculations.It is found that theΦandμMag of those MEA are proportional to the V 0,which is dominated by lattice distortion.In terms of bonding charge density,both the strengthened clusters or the so-called short-range order structures and the weakly bonded spots or weak spots are characterized.While the presence of weakly bonded Al atoms implies a large LLD/mismatch,the Fe–Mn bonding pairs result in the formation of strengthened clusters,which dominate the local microstates and the configurational transitions.The variations ofμMag are associated with the enhancement of the nearest neighbor magnetic Fe and Mn atoms,attributing to the LLD caused by Al atoms,the local changes in the electronic structures.This work provides an atomic and electronic insight into the microstate-dominated solid-solution strengthening mechanism of Fe–Mn–Al MEA.

BIM模型三维出图关键技术研究与应用

为解决BIM模型三维正向设计出图问题,基于MicroStation三维设计平台,通过二次开发方式系统研究成图及标注关键技术。通过提取剖切位置处模型切面、剖视范围内三维模型,实现剖面图底图绘制;通过将材料属性信息和剖面图关联,并配合预定义填充符号库,实现剖面图自动填充;通过将自定义数据结构在模型和图纸之间关联,实现图纸与模型联动更新;通过修改剖视图中前视范围内不可见边显示样式,实现二维剖视图中不可见边虚线显示;研发二、三维图面高程、坡比、桩号等快速标注、图框快速调用工具,实现快速成图。实例应用结果表明,该方法可明显提升基于BIM模型的二维图纸生成效率,适用直线型、折线型等不同剖面位置线图纸批量剖切,满足结构模型、地形模型、地质模型等同时剖切需求、不同出图比例图纸剖切要求、模型修改后图纸批量更新需求,研究方法和软件开发思路可为同类项目提供参考。

基于Microstation平台土石坝三维模型创建方法研究与应用

为解决土石坝三维正向设计中模型创建、工程算量、模型交付等问题,以MicroStation平台为基础采用基于.Net的Addins二次开发方式研究设计解决方案。模型创建方法采用求取土石坝分区横断面沿坝轴线拉伸或旋转形成的实体Mesh1、坝轴线沿分区横断面边界偏移构成的水平面与三维地形模型之间的竖向投影体Mesh2之间的相交体,并通过对Mesh1、Mesh2生成的控制,解决坝轴线转折位置处可能存在的模型自相交问题;工程量提取采用分区横断面材料属性和对应横断面生成的坝体分区模型关联的方式,在分区模型生成过程中同步提取工程量。研究成果适用直线型及折线型等多种类型坝轴线,适用各种复杂分区横断面的土石坝三维分区模型创建,解决了折线型坝轴线情况下因转折位置处可能存在模型自相交现象导致分区模型创建失败问题,解决了坝体分区工程量精确提取的问题,多个实际工程项目应用显示可明显提升土石坝三维正向设计的效率。研究方法及成果可为类似工程应用及软件研发提供参考借鉴。

基于BIM软件二次开发的桥梁参数化建模研究

建筑信息模型(BIM)是实现桥梁信息化的一项重要技术,但一些BIM软件难以满足桥梁设计的实际需求,需要进行二次开发实现桥梁参数化建模。本文基于BIM软件进行二次开发,结合设计人员的设计思路,从基础的钢桁梁系统线自动生成开始,到杆件截面的定义,再到系统线与杆件截面的匹配关联,最后生成钢桁梁模型,实现了设计参数到钢桁梁参数化模型的闭环。同时,对特大桥的特殊桩基础中变径不等长的群桩基础的参数化进行了研究,实现了特殊桩基础的参数化设计。通过二次开发提高了桥梁三维设计的建模效率和准确性,为桥梁在特大桥的钢桁梁和特殊桩基础的BIM参数化设计中的运用及发展提供参考。

预制箱梁结构参数优化模型构建及工程量智能统计

针对Bentley平台的三维建模基础软件Microstation无法进行桥梁结构参数化建模配筋及钢筋工程量统计问题,利用MICROSTATION SDK软件开发工具、WPF界面、选用主流开发语言C#,辅以C++/CLI,以Vi⁃sual Studio 2019为开发平台,进行二次开发。开发出了适用于该类桥梁的快速配筋插件以及钢筋工程量统计插件。以某桥梁工程中的30 m长等截面预制箱梁为例,应用箱梁建模配筋及工程量统计插件程序,高效准确地完成了30 m长等截面预制箱梁的三维建模配筋及钢筋工程量统计,验证了该二次开发建模及配筋插件程序的可用性和高效性,大大提高了设计人员的配筋及工作效率。

MicroStation矢量数据坐标转换软件实现与分析

为加速2000国家大地坐标系在石油、规划、勘测等领域的推广应用,满足MicroStation矢量数据坐标转换需求,通过分析DGN格式数据特点,确定图形元素坐标转换方法,开发了可调灵活用四参数、高精度高分辨率格网改正量的MicroStation矢量数据坐标转换软件。以陕西省中部某地作为实验区,对该区域重合点和矢量数据进行坐标转换。应用结果表明:坐标转换内符合精度达毫米级,外符合精度达厘米级,满足国家基本比例尺精度要求;转后数据接边情况、数据内容和属性与源数据保持一致,图廓整饰内容正确、完整,转换质量良好;转换效率满足实际生产需求。

MicroStation平台的参数化构件生成、修改方法研究

文章旨在MicroStation平台上开发一种新的参数化构件生成与修改方法,解决了现有技术中参数属性数据丢失及单元打散问题。通过在Model中为每个参数化构件创建一个非图形数据元素,采用序列化/反序列化算法在元素上存储或读取参数属性数据。研究通过具体步骤展示了如何利用数据结构对象和二进制数据包管理构件参数,以及如何实现构件的动态生成与修改,确保修改后构件子元素在文件中保持正确的坐标位置。此外,文章支持在MicroStation平台上存储复杂数据类型,如C++标准库中的字符串和向量,从而扩展了平台的数据处理能力。研究结果提高了三维模型的创建和修改效率,对于需要高效率和高准确性三维设计的工程项目具有重要的应用价值。

基于Bentley的重力坝三维参数化设计系统研究

基于Bentley平台的设计软件MicroStation进行二次开发,研究重力坝三维参数化设计系统。建立“模板”“骨架”概念,实现在一个集成系统中完成断面设计、抗滑稳定计算、坝体应力计算、极限状态计算、有限元分析、拦河坝布置、参数化建模、工程量自动统计和三维辅助出图等功能。对转变工程传统的设计模式、提升设计质量与效率、推动工程设计数字化进程具有重要的借鉴意义和实用价值。

融合影像的机载激光扫描点云建筑物三维重建系统设计与实现

设计了一套基于MicroStation V8i SS2的融合影像的机载激光扫描点云建筑物模型重建系统,研究若干关键技术,开发实现了从建筑物外轮廓获取到建筑物三维模型重建的一系列功能。

数字地图制图中地形图整饰的自动实现

地图整饰是数字地图制图的基本要求,能帮助地图使用者迅速、准确地判读地理信息。以中小比例尺地形图为例,阐述建立地形图数学基础的基本原理,介绍地图整饰中辅助要素的实现方法,总结实现地图整饰的技术思路。通过利用MicroStation软件所提供的二次开发功能,提高地图整饰模块开发的效率。

海图出版数据的通告改正更新技术研究

基于目前海图出版数据缺乏通告改正更新、无法实现对其再利用的现状,提出了一种利用M icroStation自动化编程技术实现通告改正更新的新方法,并解决了数字航海通告格式建立和通告改正数据分层存储等关键技术问题,在此基础上开发了海图出版数据的通告改正更新系统。

GeoStation地质三维系统图件自动编绘方法研究

GeoStation是华东院基于MicroStation软件平台二次开发的地质三维勘察设计系统。该系统有效融合了地质三维建模流程,可以通过地质数据库和地质三维模型自动编绘地质图件。使用EC Framework技术为CAD元素添加GIS属性,解决了出图数据自动提取与绘制、自动标注、图件辅助要素自动绘制等关键问题。目前,该系统已应用于多个大型水电工程中,实践表明采用GeoStation系统自动绘制地质图件,可以大幅提高地质图件的编绘效率和出图质量,经济效益显著。

CAD软件用于一体化地图制图信息系统建立与应用研究

首先对计算机地图制图与出版一体化的状况进行了概要论述。在对目前国内常用的两种一体化地图制图信息系统讨论后 ,重点对通用 CAD软件应用于彩色地图编制与出版进行了研究 ,总结出用一般 CAD软件 (非专用出版软件 )进行彩色地图编制与出版应解决的 3个关键性的共性问题 :层控制、颜色模式及 PS输出。并以通用 CAD软件—— Micro Station95为例详细说明用该软件进行彩色地图编制与出版的 3个共性问题的解决 ,并用实例加以说明。