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High Voltage 2016年第2期1卷 86-89页

作者： Yangyang Fu Shuo Yang Xiaobing Zou Haiyun Luo Xinxin Wang Department of Electrical Engineering Tsinghua UniversityBeijingPeople’s Republic of China

The similarity of gas discharge in low-pressure argon gaps between two plane-parallel electrodes was investigated by experiments,numerical simulations and theoretical analysis.It was found by the experiments that the breakdown voltages depend not only on the product of gas pressure and gap length,but also on the aspect ratio of the gap,i.e.U_(b)=f(pd,d/r).It was theoretically proved that U_(b)=f(pd,d/r)is also a special case,the non-uniform electric field between plane-parallel electrodes,of similarity theorem of gas discharge.It was found by the experiments that there exist similar glow discharges only in two gaps with a limited scaled-down factor k.By theoretical analysis,it was explained that the forbidden processes such as the stepwise ionisation and the inelastic collision of the second kind violate the similarity of discharge as k increases,which was verified by the numerical simulations of the discharges with or without these two forbidden processes taken into account.

关键词： similarity plane forbidden

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High Technology Letters 2017年第2期23卷 179-184页

作者：李文法 Wang Gongming Li Ke Huang Su Beijing Key Laboratory of Information Service Engineering Beijing Union University National Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of Sciences

The performance of conventional similarity measurement methods is affected seriously by the curse of dimensionality of high-dimensional data.The reason is that data difference between sparse and noisy dimensionalities occupies a large proportion of the similarity,leading to the dissimilarities between any results.A similarity measurement method of high-dimensional data based on normalized net lattice subspace is proposed.The data range of each dimension is divided into several intervals,and the components in different dimensions are mapped onto the corresponding interval.Only the component in the same or adjacent interval is used to calculate the similarity.To validate this method,three data types are used,and seven common similarity measurement methods are compared.The experimental result indicates that the relative difference of the method is increasing with the dimensionality and is approximately two or three orders of magnitude higher than the conventional method.In addition,the similarity range of this method in different dimensions is [0,1],which is fit for similarity analysis after dimensionality reduction.

关键词： high-dimensional data the curse of dimensionality similarity normalization subspace NPsim

Publisher Correction: Finding the semantic similarity in single-particle diffraction images using self-supervised contrastive projection learning

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npj Computational Materials 2023年第1期9卷 1732-1733页

作者： Julian Zimmermann Fabien Beguet Daniel Guthruf Bruno Langbehn Daniela Rupp ETH Zürich Zürich Switzerland Max-Born-Institut Berlin Germany Technische Universität Berlin Berlin Germany

Correction to:npj Computational Materials https://***/10.1038/s41524-023-00966-0,published online 16 February 2023 The original version of this Article contained several typographical errors in both the PDF and the HTML versions.In the first paragraph of‘Introduction’,the sentence‘(The phrase was coined by Nobel laureate Francis Crick in his book What Mad Pursuit:A personal view of scientific discovery)’duplicated reference 1.The sentence and brackets have been removed in the corrected version.

关键词： semantic similarity projection

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Acta Mathematica Sinica,English Series 2013年第4期29卷 789-800页

作者： Kui JI Rui SHI Department of Mathematics Hebei Normal University School of Mathematical Sciences Dalian University of Technology

Abstract In this paper, we give a similarity classification for the multiplication operator Mg on the Sobolev disk algebra R（D） with g analytic on the closure of the unit disk D.

关键词： Sobolev spaces Sobolev disk algebra multiplication operator similarity

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Geoscience Frontiers 2022年第1期13卷 217-229页

作者： Liang Han Lin Wang Xuanming Ding Haijia Wen Xingzhong Yuan Wengang Zhang School of Civil Engineering Chongqing UniversityChongqing 400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing 400045China National Joint Engineering Research Center of Geohazards Prevention in the Reservoir Areas Chongqing UniversityChongqing 400045China

This paper presents a confidence ellipse-based method to evaluate the similarity of soil parametric data using the database from the site investigation reports.Then,the obtained similarity assessment results of parametric data are used to further estimate the site similarity via two proposed strategies,namely the mean and weighted mean approaches.The former referred to the average of parametric data similarity degrees,while the latter was the weighted average,and the weight was calculated using the coefficient of variation(COV)of each parameter.For illustration,the liquidity index(LI)dataset was firstly used to explore the performance of the presented method in the evaluation of parametric data similarity.Subsequently,the site similarity was assessed and the effects of numbers and weights of selected parameters for study were systematically studied.Lastly,the transformation models about the relationships between Cc and x as well as between Cc and e0 were constructed to illustrate the application of the similarity analysis in reduction of transformation uncertainty.Results show that the greatest site similarity degree is at about 0.76 in this study,and the maximum decrease of transformation uncertainty can reach up to 18%and 25.5%as union parametric data similarity degree increases.Moreover,the site similarity degree represents the whole similarity between two different sites,and the presented union parameter similarity degree maintains a good agreement with transformation uncertainty.

关键词： Soil parameters Site Confidence ellipse similarity

Optimization and verification of free flight separation similarity law in high-speed wind tunnel

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Chinese Journal of Aeronautics 2020年第2期33卷 501-507页

作者： Fei XUE Xin JIN Peihua FENG Han QIN Zenghui JIANG Yuchao WANG Peng BAI China Academy of Aerospace Aerodynamics Beijing 100074China AVIC Chengdu Aircraft Design&Research Institute Chengdu 610091China Beijing Machinery and Electronics Engineering Institute Beijing 100074China

Based on the similarity of separation time,a similarity law optimization method for high-speed weapon delivery test is derived.The typical separation state under wind load is simulated by the numerical method.The real separation data of aircraft,separation data of previous test methods,separation data of ideal wind tunnel test of previous methods,and simulation data of the proposed optimization method are obtained.A comparison of the data shows that the method proposed can improve the performance of tracking.similarity law optimization starts with the development of motion equations and dynamic equations in the windless state to address the problems of mismatching between vertical and horizontal displacement,and to address the problems of separation trajectory distortion caused by insufficient gravity acceleration of the scaling model of existing light model.The ejection velocity of the model is taken as a factor/vector,and is adjusted reasonably to compensate the linear displacement insufficiency caused by the insufficient vertical acceleration of the light model method,so as to ensure the matching of the vertical and horizontal displacement of the projectile,and to improve the consistency between the test results of high-speed projection and the actual separation trajectory.The optimized similarity law is applicable to many existing free-throwing modes of high-speed wind tunnels.The optimized similarity law is not affected by the ejection velocity and hanging mode of the projectile.The optimized similarity law is suitable not only for the launching of the buried ammunition compartment and external stores,but also for the test design of projectile launching and gravity separation.

关键词： Carrier and missile interference Ejection separation Gravity separation High-speed weapon delivery Multi-body separation similarity law optimization

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Chinese Physics Letters 2021年第2期38卷 62-68页

作者：袁伟伦阴帅钟凡 State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSun Yat-sen UniversityGuangzhou 510275China

Symmetry breaking plays a pivotal role in modern physics.Although self-similarity is also a symmetry,and appears ubiquitously in nature,a fundamental question arises as to whether self-similarity breaking makes sense or not.Here,by identifying an important type of critical fluctuation,dubbed‘phases fluctuations’,and comparing the numerical results for those with self-similarity and those lacking self-similarity with respect to phases fluctuations,we show that self-similarity can indeed be broken,with significant consequences,at least in nonequilibrium situations.We find that the breaking of self-similarity results in new critical exponents,giving rise to a violation of the well-known finite-size scaling,or the less well-known finite-time scaling,and different leading exponents in either the ordered or the disordered phases of the paradigmatic Ising model on two-or three-dimensional finite lattices,when subject to the simplest nonequilibrium driving of linear heating or cooling through its critical point.This is in stark contrast to identical exponents and different amplitudes in usual critical phenomena.Our results demonstrate how surprising driven nonequilibrium critical phenomena can be.The application of this theory to other classical and quantum phase transitions is also anticipated.

关键词： similarity breaking critical

Finding the semantic similarity in single-particle diffraction images using self-supervised contrastive projection learning

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npj Computational Materials 2023年第1期9卷 2118-2126页

作者： Julian Zimmermann Fabien Beguet Daniel Guthruf Bruno Langbehn Daniela Rupp ETH Zürich ZürichSwitzerland Technische Universität Berlin BerlinGermany Max-Born-Institut BerlinGermany

Single-shot coherent diffraction imaging of isolated nanosized particles has seen remarkable success in recent years,yielding in-situ measurements with ultra-high spatial and temporal resolution.The progress of high-repetition-rate sources for intense X-ray pulses has further enabled recording datasets containing millions of diffraction images,which are needed for the structure determination of specimens with greater structural variety and dynamic experiments.The size of the datasets,however,represents a monumental problem for their analysis.Here,we present an automatized approach for finding semantic similarities in coherent diffraction images without relying on human expert labeling.By introducing the concept of projection learning,we extend self-supervised contrastive learning to the context of coherent diffraction imaging and achieve a dimensionality reduction producing semantically meaningful embeddings that align with physical intuition.The method yields substantial improvements compared to previous approaches,paving the way toward real-time and large-scale analysis of coherent diffraction experiments at X-ray free-electron lasers.

关键词： projection coherent similarity

Complex neutrosophic generalised dice similarity measures and their application to decision making

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CAAI Transactions on Intelligence Technology 2020年第2期5卷 78-87页

作者： Zeeshan Ali Tahir Mahmood Department of Mathematics and Statistics International Islamic UniversityIslamabadPakistan

Complex neutrosophic set(CNS)is a modified version of the complex fuzzy set,to cope with complicated and inconsistent information in the environment of fuzzy set theory.The CNS is characterised by three functions expressing the degree of complex-valued membership,complex-valued abstinence and degree of complex-valued non-membership.The aim of this manuscript is to initiate the novel dice similarity measures and generalised dice similarity using CNS.The special cases of the investigated measures are discussed with the help of some remarks.Moreover,some distance measures based on CNS are also proposed in this manuscript.Then,the authors applied the generalised dice similarity measures and weighted generalised dice similarity measures using CNS to the pattern recognition model to examine the reliability and superiority of the established approaches.The advantages and comparative analysis of the proposed measures with existing measures are also discussed in detail.At last,a numerical example is provided to illustrate the validity and applicability of the presented measures.

关键词： theory. similarity valued