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Classification of knowledge graph completeness measurement techniques

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Journal of Systems Engineering and Electronics 2024年第1期35卷 154-162页

作者： ZHANG ying XIAO Gang Institute of Systems Engineering Academy of Military SciencesBeijing 100107China

At present,although knowledge graphs have been widely used in various fields such as recommendation systems,question and answer systems,and intelligent search,there are always quality problems such as knowledge omissions and *** assessment and control,as an important means to ensure the quality of knowledge,can make the applications based on knowledge graphs more complete and more accurate by reasonably assessing the knowledge graphs and fixing and improving the quality problems at the same ***,as an indispensable part of the knowledge graph construction process,the results of quality assessment and control determine the usefulness of the knowledge *** them,the assessment and enhancement of completeness,as an important part of the assessment and control phase,determine whether the knowledge graph can fully reflect objective phenomena and reveal potential connections among *** this paper,we review specific techniques of completeness assessment and classify completeness assessment techniques in terms of closed world assumptions,open world assumptions,and partial completeness *** purpose of this paper is to further promote the development of knowledge graph quality control and to lay the foundation for subsequent research on the completeness assessment of knowledge graphs by reviewing and classifying completeness assessment techniques.

关键词： quality assessment completeness assessment closed world assumptions open world assumption partial completeness assumption

Total Focusing Method Damage Imaging in Frequency Domain Using Laser-Ultrasonic Lamb Wave Based on Time-domain Filtering in Multi-band

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Acta Mechanica Solida Sinica 2021年第3期34卷 404-424页

作者： Fengzhong Li ying Luo National Center for International Research on Structural Health Management of Critical Components Jiangsu UniversityZhenjiang 212013China

A fully non-contact experimental platform for ultrasonic Lamb wave damage detection was constructed,where laser exciting and the scanning laser Doppler vibrometer were used to realize the high-resolution pickup of the Lamb wave field in the structure,which has overcome the disadvantages of low spatial resolution caused by the conventional contact Lamb wave *** order to suppress the dispersion effect of broadband laser-ultrasonic signal,we proposed time-domain filtering in multi-band method based on wavelet analysis to decompose the broadband signal into multiple narrowband ones and separate the scattering signals effectively without reference *** this basis,the total focusing method(TFM)was used for damage ***,when the traditional TFM was applied to image based on ultrasonic Lamb wave,the inherent dispersion characteristic of ultrasonic Lamb wave could lead to the miscalculation of time delay,thus reducing the imaging ***,the frequency-domain TFM was developed by applying phase delay in the frequency *** logical AND was introduced to synthesize the damage imaging results of multiple narrowband signals to obtain high-precision damage *** study has shown that the method of time-domain filtering in multi-band combining with frequency-domain TFM can realize non-contact and accurate damage detection in isotropic plate structures,and it is a potential effective method for application in engineering practice.

关键词： Laser ultrasound Lamb wave Multi-band Wavelet analysis Dispersion Total focusing method

An Improved Gravitational Search Algorithm for Dynamic Neural Network Identification

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International Journal of Automation and computing 2014年第4期11卷 434-440页

作者： Bao-Chang Xu ying-ying Zhang Department of Automation China University of Petroleum (Beijing)

Gravitational search algorithm(GSA) is a newly developed and promising algorithm based on the law of gravity and interaction between masses. This paper proposes an improved gravitational search algorithm(IGSA) to improve the performance of the GSA, and first applies it to the field of dynamic neural network identification. The IGSA uses trial-and-error method to update the optimal agent during the whole search process. And in the late period of the search, it changes the orbit of the poor agent and searches the optimal agent s position further using the coordinate descent method. For the experimental verification of the proposed algorithm,both GSA and IGSA are testified on a suite of four well-known benchmark functions and their complexities are compared. It is shown that IGSA has much better efficiency, optimization precision, convergence rate and robustness than GSA. Thereafter, the IGSA is applied to the nonlinear autoregressive exogenous(NARX) recurrent neural network identification for a magnetic levitation *** with the system identification based on gravitational search algorithm neural network(GSANN) and other conventional methods like BPNN and GANN, the proposed algorithm shows the best performance.

关键词： Gravitational search algorithm orbital change optimization neural network system identification

Quantifying the Research Diversification of Physicists

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Journal of Systems Science and Systems Engineering 2021年第6期30卷 712-727页

作者： Jianlin Zhou ying Fan School of Economics and Management China University of Geosciences(Beijing)Beijing 100083China School of Systems Science Beijing Normal UniversityBeijing 100875China

Scientists may shift research interests and span multiple research areas in their careers,reflecting the research diversification of *** the scientists,research diversity can help to understand the research patterns of *** this paper,we study the research diversification of scientists in Physics based on the Physics and Astronomy Classification Scheme(PACS)which can well reflect the research topics of physics *** each scientist,we first build a PACS codes co-occurrence network and reveal the research diversity by analyzing the connectivity and community structure of this *** we use diversity indicators to measure the research diversification of scientists and analyze the distribution of each ***,we investigate the relationship between scientists7 diversity indicators and their scientific impact using multiple regression *** results show that the numbers of connected components of most PACS codes co-occurrence networks are less than 5,and some networks have significant community *** diversity indicators show the heterogeneity of the research diversity of *** also find that some diversity indicators are weakly correlated with scientific impact *** on our findings,we suggest that physicists should focus on their main research fields and span multiple research fields over their entire careers which could promote their scientific impact.

关键词： Research diversification co-occurrence network community structure scientific impact

The K°-relation on the Congruence Lattice of a Regular Semigroup with an Inverse Transversal

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Acta Mathematica Sinica,English Series 2012年第5期28卷 1061-1074页

作者： ying ying FENG Li Min WANG Department of Information Science and Mathematics Foshan University School of Mathematics South China Normal University

Let S be a regular semigroup with an inverse transversal S° and C（S） the congruence lattice of S. A relation K° on C（S） is introduced as follows： if p, θ∈ C（S）, then we say that p and 0 are K°-related if Ker pO = Ker θ°, where p°= p｜s°. Expressions for the least and the greatest congruences in the same K°-class as p are provided. A number of equivalent conditions for K° being a congruence are given.

关键词： Regular semigroup inverse transversal congruence K°-relation

A Lower Bound for the Algebraic Connectivity of a Graph in Terms of the Domination Number

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Acta Mathematicae Applicatae Sinica 2018年第4期34卷 752-760页

作者： Yi-Zheng FAN ying-ying TAN School of Mathematical Sciences Anhui University Hefei 230601 P. R. China School of Mathematics and Physics Anhui Jianzhu University Hefei 230601 China

We investigate how the algebraic connectivity of a graph changes by relocating a connected branch from one vertex to another vertex, and then minimize the algebraic connectivity among all connected graphs of order n with fixed domination number γ≤（n＋2）/3, and finally present a lower bound for the algebraic connectivity in terms of the domination number. We also characterize the minimum algebraic connectivity of graphs with domination number half their order.

关键词： graph algebraic connectivity domination number

Research and Application of Machine Learning in Automatic Program Generation

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Chinese Journal of Electronics 2020年第6期29卷 1001-1015页

作者： ZHANG Xiaojiang JIANG ying Yunnan Key Laboratory of Computer Technology Application Kunming University of Science and Technology Faculty of Information Engineering and Automation Kunming University of Science and Technology

With the development of artificial intelligence,machine learning has been applied in more and more *** order to improve the quality and efficiency of software,automatic program generation is becoming a research *** recent years,machine learning has also been gradually applied in automatic program *** trees,language models,and cyclic neural networks have been applied in code generation,code completion and code knowledge *** efficiency of software development has been improved to a certain extent using machine *** at the automatic program generation,this paper analyzes and summarizes the models of machine learning,the modifications involved in the models and the application *** research direction is discussed from the aspects of programmer behavior and automatic program generation of machine learning.

关键词： automatic programming data mining decision trees learning (artificial intelligence) neural nets software engineering programmer behavior cyclic neural networks language models decision trees code knowledge mining code completion code generation automatic program generation machine learning Machine learning Code generation Code completion Code knowledge mining Application effect

Recognizing Social Function of Urban Regions by Using Data of Public Bicycle Systems

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Chinese Journal of Electronics 2019年第1期28卷 13-20页

作者： XU Haitao ying Jing College of Computer Science and Technology Zhejiang University

Obtaining the classification of urban functions is an integral part of urban planning. Currently,public bicycle systems are booming in these years. It conveys human mobility and activity information, which can be closely related to the social function of an urban region. This paper discusses the potential use of public bicycle systems for recognizing the social function of urban regions by using one year’s rent/return data of public bicycles. We found that rent/return dynamics, extracted from public bicycle systems, exhibited clear patterns corresponding to the urban function classes of these regions. With seven features designed to characterize the rent/return pattern, our method based on Smooth support vector machine(SSVM) is proposed to recognize social function classes of urban regions. We evaluate our method based on the large-scale real-world dataset collected from the public bicycle system of Hangzhou. The results show that our method can efficiently recognize different types of urban function areas. Classification results using the proposed SSVM achieved the best classification accuracy of 96.15%.

关键词： Urban regions recognition Public bicycle system Social function classification Smooth support vector machine(SSVM)

An Experimental Study on the Phenomena inside the Burning Aviation Kerosene Droplet

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Journal of Thermal Science 2021年第6期30卷 2202-2213页

作者： HE Ming PIAO ying School of Aerospace Engineering Tsinghua UniversityBeijing 100084China

This paper conducted an experimental study of droplet behavior characteristics occurring within a burning aviation kerosene droplet and on the droplet *** droplet combustion was performed in a quiescent high-temperature environment by means of the droplet suspension *** soot particles were used as tracers to visualize the fluid motion in the *** shape variation of droplet,internal flow pattern in the burning droplet,and instabilities at gas-liquid phase interface were recorded by a high speed *** internal fluid flow in the droplet was revealed to be caused by the Marangoni effect,which was generated because of the surface tension gradient induced by the temperature gradient on the droplet *** studies showed that the Marangoni effect has a significant impact on the internal *** amplitude of the capillary waves on the surface of the droplet was non-uniform and presented the amplitude characteristics of *** wavelength of the capillary waves for burning aviation kerosene droplet ranged from 110μm to 120μm.

关键词： droplet combustion internal flow Marangoni effect capillary waves