Directly calculating the topolo gi cal and geometric complexity from the STEP (standard for the exchange of product model data, ISO 10303) file is a huge task. So, a case-based reasoning approac h is presented, which...Directly calculating the topolo gi cal and geometric complexity from the STEP (standard for the exchange of product model data, ISO 10303) file is a huge task. So, a case-based reasoning approac h is presented, which is based on the similarity between the new component and t he old one, to calculate the topological and geometric complexity of new compone nts. In order to index, retrieve in historical component database, a new way of component representation is brought forth. And then an algorithm is given to ext ract topological graph from its STEP files. A mathematical model, which describe s how to compare the similarity, is discussed. Finally, an example is given to s how the result.展开更多
The dynamical system on T^2 which is a group extension over an irrational rotation on T^1 is investigated. The criterion when the extension is minimal, a system of order 2 and when the maximal equicontinuous factor is...The dynamical system on T^2 which is a group extension over an irrational rotation on T^1 is investigated. The criterion when the extension is minimal, a system of order 2 and when the maximal equicontinuous factor is the irrational rotation is given. The topological complexity of the extension is computed, and a negative answer to the latter part of an open question raised by Host et al.(2014) is obtained.展开更多
In our efforts to construct new metal-organic frameworks （MOFs） by template-directing method, a new cadmium oxalate, [Co（NH3）612[Cds（C204）ll（H20）4].8H20 （denoted HNU-1 ）, has been synthesized under hydrother...In our efforts to construct new metal-organic frameworks （MOFs） by template-directing method, a new cadmium oxalate, [Co（NH3）612[Cds（C204）ll（H20）4].8H20 （denoted HNU-1 ）, has been synthesized under hydrothermal condition in the presence of C0（NH3）6C13, The crystal structure of HNU-1 was determined by single-crystal X-ray diffraction （monoclinic, C2/c）, a = 11.126（2）A, b = 17.361 （4）,A, c = 16.119（3）A, fi = 102.40（3）, V = 3040.8（10） A and Z = 8. The open framework of HNU-1 contains 12-ring channels and exhibits a 5-connected sqp topological network with dinuclear Cd（ll） clusters acting as nodes. The Co（NH3）63＋ cations and unusual hydrogen-bonded （H20）4 clusters are found in the 12-ring channels with an alternative arrangement. It is believed that the （H20）4 clusters play a co-templating role in the crystallization of HNU-1.展开更多
As a matter of fact,most natural structures are complex topology structures with intricate holes or irregular surface morphology.These structures can be used as lightweight infill,porous scaffold,energy absorber or mi...As a matter of fact,most natural structures are complex topology structures with intricate holes or irregular surface morphology.These structures can be used as lightweight infill,porous scaffold,energy absorber or micro-reactor.With the rapid advancement of 3D printing,the complex topology structures can now be efficiently and accurately fabricated by stacking layered materials.The novel manufacturing technology and application background put forward new demands and challenges to the current design methodologies of complex topology structures.In this paper,a brief review on the development of recent complex topology structure design methods was provided;meanwhile,the limitations of existing methods and future work are also discussed in the end.展开更多
As the topology of DeviceNet in industrial automation systems grows more complex and the reliability requirement for industrial equipment and processes becomes more stringent,the importance of network troubleshooting ...As the topology of DeviceNet in industrial automation systems grows more complex and the reliability requirement for industrial equipment and processes becomes more stringent,the importance of network troubleshooting is increasingly evident.Intermittent connection(IC)faults frequently occur in DeviceNet systems,impairing production performance and even operational safety.However,existing IC troubleshooting methods for DeviceNet,especially those with complex topologies,cannot directly handle multi-fault scenarios,which require human intervention for a full diagnosis.In this paper,a novel data-driven IC fault diagnosis method based on Bayesian inference is proposed for DeviceNet with complex topologies,which can accurately and efficiently localize all IC faults in the network without interrupting the normal system operation.First,the observation symptoms are defined by analyzing the data frames interrupted by IC faults,and the suspected IC faults are derived by integrating the observation symptoms and the network topology information.Second,a Bayesian inference-based estimation approach for the posterior probability of each suspected fault occurring in the network is proposed using the quantity of observation symptoms and their causal relationships regarding the suspected faults.Finally,a maximum likelihood-based fast diagnosis algorithm is developed to rapidly identify the IC fault locations in various complex scenarios.A laboratory testbed is constructed and case studies are conducted under various topologies and fault scenarios to demonstrate the effectiveness and advantages of the proposed method.Experimental results show that the IC fault locations diagnosed by the proposed method agree well with the experimental setup.展开更多
Spatio-temporal heterogeneous data is the database for decisionmaking in many fields,and checking its accuracy can provide data support for making decisions.Due to the randomness,complexity,global and local correlatio...Spatio-temporal heterogeneous data is the database for decisionmaking in many fields,and checking its accuracy can provide data support for making decisions.Due to the randomness,complexity,global and local correlation of spatiotemporal heterogeneous data in the temporal and spatial dimensions,traditional detection methods can not guarantee both detection speed and accuracy.Therefore,this article proposes a method for detecting the accuracy of spatiotemporal heterogeneous data by fusing graph convolution and temporal convolution networks.Firstly,the geographic weighting function is introduced and improved to quantify the degree of association between nodes and calculate the weighted adjacency value to simplify the complex topology.Secondly,design spatiotemporal convolutional units based on graph convolutional neural networks and temporal convolutional networks to improve detection speed and accuracy.Finally,the proposed method is compared with three methods,ARIMA,T-GCN,and STGCN,in real scenarios to verify its effectiveness in terms of detection speed,detection accuracy and stability.The experimental results show that the RMSE,MAE,and MAPE of this method are the smallest in the cases of simple connectivity and complex connectivity degree,which are 13.82/12.08,2.77/2.41,and 16.70/14.73,respectively.Also,it detects the shortest time of 672.31/887.36,respectively.In addition,the evaluation results are the same under different time periods of processing and complex topology environment,which indicates that the detection accuracy of this method is the highest and has good research value and application prospects.展开更多
CONSPECTUS:Nature presents us with numerous complex topological structures,among which ordered bicontinuous structures are widely found in biological systems and exhibit numerous functions,as exemplified by the vibran...CONSPECTUS:Nature presents us with numerous complex topological structures,among which ordered bicontinuous structures are widely found in biological systems and exhibit numerous functions,as exemplified by the vibrant wings of butterflies and the robust skeletons of knobby starfish.In recent decades,significant strides have been made in preparing functional materials with bicontinuous porous structures,e.g.,cubosomes�spherical colloidal particles,which encompass continuous pores and frameworks arranged in a cubic crystal lattice.These cubosomes exhibit many remarkable advantages due to their unique periodic topological structure.(1)The three-dimensional(3D)interconnected pores facilitate the smooth transport of substances throughout the material,resulting in at least a three times higher utilization ratio of internal active sites compared to that of their unconnected pore or nonporous counterparts.Their complex,tortuous,and periodic porous configuration can enhance energy capture,such as solar/electric energy.(2)The 3D continuous pore channels and frameworks provide“highways”for ion and electron transport,leading to an order-of-magnitude reduction in charge-transfer resistance and an over 3-fold increase in the ion diffusion coefficient compared to those of nonporous analogues,thereby improving the electrochemical kinetics of electrodes.(3)Cubosomes have emerged as unique mechanical metamaterials,exhibiting a remarkable capability to alleviate mechanical stress and strain.(4)Their negative-Gaussian-curvature surfaces facilitate the adsorption/desorption of reaction intermediates,thereby lowering the reaction free energy in catalytic reaction processes.Additionally,this distinctive surface structure can enhance the electric field intensity at material interfaces,significantly promoting ion adsorption.With these advantages,functional cubosomes show potential for application in the field of energy storage and conversion.However,due to the big challenges in their preparation,there have been limited studies on their structure−activity relationships in energy-related applications.Therefore,there has not yet been a review regarding functional cubosomes.In this Account,we summarize mainly our latest progress in the study of functional cubosomes.First,we introduce the preparation of polymer cubosomes(PCs)through the self-assembly of block copolymers in solution,along with plotting their morphological phase diagram.Then,the Account describes nanocasting approaches in which polymer cubosomes are employed as templates to prepare a variety of functional cubosomes,including polymers,covalent organic frameworks(COFs),metal−organic frameworks(MOFs),metal−phenolic networks,carbons,inorganic metal compounds,and metals.Finally,to elucidate the application prospects of the functional cubosomes,this Account discusses their advantages in different energy storage and conversion applications,highlighting efficient material and energy utilization,fast mass and electron transport,negative-Gaussian-curvature surfaces,and excellent mechanical stability.We anticipate that this Account will demystify functional cubosomes with bicontinuous porous structures and stimulate their broad interest in the fields of materials science,chemistry,and energy,among others.展开更多
In this paper, we investigate by numerical simulations the Bak-Sneppenmodel (BSM) for biological evolution on scale-free networks (SFNs) with various degree exponents γ. We find that the punctuated equilibrium is rat...In this paper, we investigate by numerical simulations the Bak-Sneppenmodel (BSM) for biological evolution on scale-free networks (SFNs) with various degree exponents γ. We find that the punctuated equilibrium is rather robust with respect to the network topology. Furthermore, we analyze the evolution of the criticalaverage fitness h fi ∗ and the exponent τ of h fi 0 avalanche as a function of α (i.e., the degree exponent γ). Our observations indicate the dependence of evolutionary dynamicsof BSM on the complex biosystem topology.展开更多
Link prediction is an important task that estimates the probability of there being a link between two disconnected nodes. The similarity-based algorithm is a very popular method that employs the node similarities to f...Link prediction is an important task that estimates the probability of there being a link between two disconnected nodes. The similarity-based algorithm is a very popular method that employs the node similarities to find links. Most of these types of algorithms focus only on the contribution of common neighborhoods between two nodes. In sociological theory relationships within three degrees are the strong ties that can trigger social behaviors.Thus, strong ties can provide more connection opportunities for unconnected nodes in the networks. As critical topological properties in networks, nodes degrees and node clustering coefficients are well-suited for describing the tightness of connections between nodes. In this paper, we characterize node similarity by utilizing the strong ties of the ego network（i.e., paths within three degrees） and its close connections（node degrees and node clustering coefficients）. We propose a link prediction algorithm that combines topological properties with strong ties, which we called the TPSR algorithm. This algorithm includes TPSR2, TPSR3, and the TPSR4 indices. We evaluate the performance of the proposed algorithm using the metrics of precision and the Area Under the Curve（AUC）. Our experimental results show the TPSR algorithm to perform remarkably better than others.展开更多
The analysis of software system evolution is highly significant in software research as the evolution runs throughout the lifecycle of a software system. Considering a software system as an algebraic engineering syste...The analysis of software system evolution is highly significant in software research as the evolution runs throughout the lifecycle of a software system. Considering a software system as an algebraic engineering system, we propose a software system evolution analysis method based on algebraic topology. First, from a complex network perspective, we abstract a software system into the software structural topology diagram. Then, based on the algebraic topology principle, we abstract each node in the software structural topology diagram into an algebraic component represented by a 6-tuple. We propose three kinds of operation relationships between two algebraic components, so that the software system can be abstracted into an algebraic expression of components. In addition, we propose three forms of software system evolution, which help to analyze the structure and evolution of system software and facilitate its maintenance and reconfiguration.展开更多
文摘Directly calculating the topolo gi cal and geometric complexity from the STEP (standard for the exchange of product model data, ISO 10303) file is a huge task. So, a case-based reasoning approac h is presented, which is based on the similarity between the new component and t he old one, to calculate the topological and geometric complexity of new compone nts. In order to index, retrieve in historical component database, a new way of component representation is brought forth. And then an algorithm is given to ext ract topological graph from its STEP files. A mathematical model, which describe s how to compare the similarity, is discussed. Finally, an example is given to s how the result.
基金National Natural Science Foundation of China (Grant Nos. 11225105 and 11371339)
文摘The dynamical system on T^2 which is a group extension over an irrational rotation on T^1 is investigated. The criterion when the extension is minimal, a system of order 2 and when the maximal equicontinuous factor is the irrational rotation is given. The topological complexity of the extension is computed, and a negative answer to the latter part of an open question raised by Host et al.(2014) is obtained.
基金supported by the National Natural Science Foundation of China (No. 21101047)the Program for New Century Excellent Talents in University (No. NCET-11-0929)+1 种基金the Natural Science Foundation of Hainan Province (No. 211010)the Priming Scientifc Research Foundation of Hainan University (No. kyqd1051)
文摘In our efforts to construct new metal-organic frameworks （MOFs） by template-directing method, a new cadmium oxalate, [Co（NH3）612[Cds（C204）ll（H20）4].8H20 （denoted HNU-1 ）, has been synthesized under hydrothermal condition in the presence of C0（NH3）6C13, The crystal structure of HNU-1 was determined by single-crystal X-ray diffraction （monoclinic, C2/c）, a = 11.126（2）A, b = 17.361 （4）,A, c = 16.119（3）A, fi = 102.40（3）, V = 3040.8（10） A and Z = 8. The open framework of HNU-1 contains 12-ring channels and exhibits a 5-connected sqp topological network with dinuclear Cd（ll） clusters acting as nodes. The Co（NH3）63＋ cations and unusual hydrogen-bonded （H20）4 clusters are found in the 12-ring channels with an alternative arrangement. It is believed that the （H20）4 clusters play a co-templating role in the crystallization of HNU-1.
基金supported by Science Fund for Creative Research Groups of National Natural Science Foundation of China(No.51521064)the National Nature Science Foundation of China(No.51575483).
文摘As a matter of fact,most natural structures are complex topology structures with intricate holes or irregular surface morphology.These structures can be used as lightweight infill,porous scaffold,energy absorber or micro-reactor.With the rapid advancement of 3D printing,the complex topology structures can now be efficiently and accurately fabricated by stacking layered materials.The novel manufacturing technology and application background put forward new demands and challenges to the current design methodologies of complex topology structures.In this paper,a brief review on the development of recent complex topology structure design methods was provided;meanwhile,the limitations of existing methods and future work are also discussed in the end.
基金supported by the National Natural Science Foundation of China(No.52072341)。
文摘As the topology of DeviceNet in industrial automation systems grows more complex and the reliability requirement for industrial equipment and processes becomes more stringent,the importance of network troubleshooting is increasingly evident.Intermittent connection(IC)faults frequently occur in DeviceNet systems,impairing production performance and even operational safety.However,existing IC troubleshooting methods for DeviceNet,especially those with complex topologies,cannot directly handle multi-fault scenarios,which require human intervention for a full diagnosis.In this paper,a novel data-driven IC fault diagnosis method based on Bayesian inference is proposed for DeviceNet with complex topologies,which can accurately and efficiently localize all IC faults in the network without interrupting the normal system operation.First,the observation symptoms are defined by analyzing the data frames interrupted by IC faults,and the suspected IC faults are derived by integrating the observation symptoms and the network topology information.Second,a Bayesian inference-based estimation approach for the posterior probability of each suspected fault occurring in the network is proposed using the quantity of observation symptoms and their causal relationships regarding the suspected faults.Finally,a maximum likelihood-based fast diagnosis algorithm is developed to rapidly identify the IC fault locations in various complex scenarios.A laboratory testbed is constructed and case studies are conducted under various topologies and fault scenarios to demonstrate the effectiveness and advantages of the proposed method.Experimental results show that the IC fault locations diagnosed by the proposed method agree well with the experimental setup.
基金supported by the National Natural Science Foundation of China under Grants 42172161by the Heilongjiang Provincial Natural Science Foundation of China under Grant LH2020F003+2 种基金by the Heilongjiang Provincial Department of Education Project of China under Grants UNPYSCT-2020144by the Innovation Guidance Fund of Heilongjiang Province of China under Grants 15071202202by the Science and Technology Bureau Project of Qinhuangdao Province of China under Grants 202101A226.
文摘Spatio-temporal heterogeneous data is the database for decisionmaking in many fields,and checking its accuracy can provide data support for making decisions.Due to the randomness,complexity,global and local correlation of spatiotemporal heterogeneous data in the temporal and spatial dimensions,traditional detection methods can not guarantee both detection speed and accuracy.Therefore,this article proposes a method for detecting the accuracy of spatiotemporal heterogeneous data by fusing graph convolution and temporal convolution networks.Firstly,the geographic weighting function is introduced and improved to quantify the degree of association between nodes and calculate the weighted adjacency value to simplify the complex topology.Secondly,design spatiotemporal convolutional units based on graph convolutional neural networks and temporal convolutional networks to improve detection speed and accuracy.Finally,the proposed method is compared with three methods,ARIMA,T-GCN,and STGCN,in real scenarios to verify its effectiveness in terms of detection speed,detection accuracy and stability.The experimental results show that the RMSE,MAE,and MAPE of this method are the smallest in the cases of simple connectivity and complex connectivity degree,which are 13.82/12.08,2.77/2.41,and 16.70/14.73,respectively.Also,it detects the shortest time of 672.31/887.36,respectively.In addition,the evaluation results are the same under different time periods of processing and complex topology environment,which indicates that the detection accuracy of this method is the highest and has good research value and application prospects.
基金supported by the National Natural Science Foundation of China(22225501,W2412102,52421006,22305149,52303275,and 52203268)the Shanghai Municipal Science and Technology Major Project,and SJTU 2030B plan(WH510207202).
文摘CONSPECTUS:Nature presents us with numerous complex topological structures,among which ordered bicontinuous structures are widely found in biological systems and exhibit numerous functions,as exemplified by the vibrant wings of butterflies and the robust skeletons of knobby starfish.In recent decades,significant strides have been made in preparing functional materials with bicontinuous porous structures,e.g.,cubosomes�spherical colloidal particles,which encompass continuous pores and frameworks arranged in a cubic crystal lattice.These cubosomes exhibit many remarkable advantages due to their unique periodic topological structure.(1)The three-dimensional(3D)interconnected pores facilitate the smooth transport of substances throughout the material,resulting in at least a three times higher utilization ratio of internal active sites compared to that of their unconnected pore or nonporous counterparts.Their complex,tortuous,and periodic porous configuration can enhance energy capture,such as solar/electric energy.(2)The 3D continuous pore channels and frameworks provide“highways”for ion and electron transport,leading to an order-of-magnitude reduction in charge-transfer resistance and an over 3-fold increase in the ion diffusion coefficient compared to those of nonporous analogues,thereby improving the electrochemical kinetics of electrodes.(3)Cubosomes have emerged as unique mechanical metamaterials,exhibiting a remarkable capability to alleviate mechanical stress and strain.(4)Their negative-Gaussian-curvature surfaces facilitate the adsorption/desorption of reaction intermediates,thereby lowering the reaction free energy in catalytic reaction processes.Additionally,this distinctive surface structure can enhance the electric field intensity at material interfaces,significantly promoting ion adsorption.With these advantages,functional cubosomes show potential for application in the field of energy storage and conversion.However,due to the big challenges in their preparation,there have been limited studies on their structure−activity relationships in energy-related applications.Therefore,there has not yet been a review regarding functional cubosomes.In this Account,we summarize mainly our latest progress in the study of functional cubosomes.First,we introduce the preparation of polymer cubosomes(PCs)through the self-assembly of block copolymers in solution,along with plotting their morphological phase diagram.Then,the Account describes nanocasting approaches in which polymer cubosomes are employed as templates to prepare a variety of functional cubosomes,including polymers,covalent organic frameworks(COFs),metal−organic frameworks(MOFs),metal−phenolic networks,carbons,inorganic metal compounds,and metals.Finally,to elucidate the application prospects of the functional cubosomes,this Account discusses their advantages in different energy storage and conversion applications,highlighting efficient material and energy utilization,fast mass and electron transport,negative-Gaussian-curvature surfaces,and excellent mechanical stability.We anticipate that this Account will demystify functional cubosomes with bicontinuous porous structures and stimulate their broad interest in the fields of materials science,chemistry,and energy,among others.
基金L.Guo thanks Prof.W.Li for his valuable suggestions and comments.This work was supported by the NSFC(10635020)the programme of Introducing Talents of Discipline to Universities under Grant No.B08033+1 种基金the State Key Development Program of Basic Research of China(2008CB317103)the Key Project of Chinese Ministry of Education(306022 and IRT0624).
文摘In this paper, we investigate by numerical simulations the Bak-Sneppenmodel (BSM) for biological evolution on scale-free networks (SFNs) with various degree exponents γ. We find that the punctuated equilibrium is rather robust with respect to the network topology. Furthermore, we analyze the evolution of the criticalaverage fitness h fi ∗ and the exponent τ of h fi 0 avalanche as a function of α (i.e., the degree exponent γ). Our observations indicate the dependence of evolutionary dynamicsof BSM on the complex biosystem topology.
基金partially supported by the National Natural Science Foundation of China(Nos.61673020,61402006,and 61702003)the National High-Tech Research and Development(863)Program of China(No.2015AA124102)+1 种基金Humanities and Social Science Research on Youth Fund Project,Ministry of Education(No.14YJC860020)Anhui Provincial Natural Science Foundation(No.1708085MF160)
文摘Link prediction is an important task that estimates the probability of there being a link between two disconnected nodes. The similarity-based algorithm is a very popular method that employs the node similarities to find links. Most of these types of algorithms focus only on the contribution of common neighborhoods between two nodes. In sociological theory relationships within three degrees are the strong ties that can trigger social behaviors.Thus, strong ties can provide more connection opportunities for unconnected nodes in the networks. As critical topological properties in networks, nodes degrees and node clustering coefficients are well-suited for describing the tightness of connections between nodes. In this paper, we characterize node similarity by utilizing the strong ties of the ego network（i.e., paths within three degrees） and its close connections（node degrees and node clustering coefficients）. We propose a link prediction algorithm that combines topological properties with strong ties, which we called the TPSR algorithm. This algorithm includes TPSR2, TPSR3, and the TPSR4 indices. We evaluate the performance of the proposed algorithm using the metrics of precision and the Area Under the Curve（AUC）. Our experimental results show the TPSR algorithm to perform remarkably better than others.
基金supported by the National Natural Science Foundation of China (No. U1636115)the National Key R&D Program of China (No. 2016YFB0800700)
文摘The analysis of software system evolution is highly significant in software research as the evolution runs throughout the lifecycle of a software system. Considering a software system as an algebraic engineering system, we propose a software system evolution analysis method based on algebraic topology. First, from a complex network perspective, we abstract a software system into the software structural topology diagram. Then, based on the algebraic topology principle, we abstract each node in the software structural topology diagram into an algebraic component represented by a 6-tuple. We propose three kinds of operation relationships between two algebraic components, so that the software system can be abstracted into an algebraic expression of components. In addition, we propose three forms of software system evolution, which help to analyze the structure and evolution of system software and facilitate its maintenance and reconfiguration.
