Optical transport networks are now the basic infrastructure of modern communications systems, including the SDH and WDM backbone network of local network operators, in the case of Cameroon. Given the colossal investme...Optical transport networks are now the basic infrastructure of modern communications systems, including the SDH and WDM backbone network of local network operators, in the case of Cameroon. Given the colossal investments required to deploy these networks, particularly related to the cost of equipment (optical fibers, transponders and multiplexers), the optimization of bandwidth and dynamic allocation of resources is essential to control operating costs and ensure continuity of service. Automatic switching technology for optical networks brings intelligence to the control plane to fully facilitate bandwidth utilization, traffic redirection, and automatic configuration of end-to-end services. This paper considers a local network operator’s WDM network without the implementation of the automatic switching technology, develops a network modeling software platform called Graphic Networks and using graph theory integrates a particularity of the automatic switching technology, which is the automatic rerouting of traffic in case of incident in the network. The incidents considered here are those links or route failures and node failures.展开更多
In this paper,different kinds of enzymes,immune factors and regulatory factors of the immune system of crustaceans are summarized and then combed systematically and thoroughly. According to the mutual influence and ef...In this paper,different kinds of enzymes,immune factors and regulatory factors of the immune system of crustaceans are summarized and then combed systematically and thoroughly. According to the mutual influence and effects of these factors,different symbolic forms are introduced to express the effects,and ultimately the whole node graph of the system is obtained. The graph theory can be used for further researches on the immune system of crustacean.展开更多
It is difficult to rescue people from outside, and emergency evacuation is still a main measure to decrease casualties in high-rise building fires. To improve evacuation efficiency, a valid and easily manipulated grou...It is difficult to rescue people from outside, and emergency evacuation is still a main measure to decrease casualties in high-rise building fires. To improve evacuation efficiency, a valid and easily manipulated grouping evacuation strategy is proposed. Occupants escape in groups according to the shortest evacuation route is determined by graph theory. In order to evaluate and find the optimal grouping, computational experiments are performed to design and simulate the evacuation processes. A case study shown the application in detail and quantitative research conclusions is obtained. The thoughts and approaches of this study can be used to guide actual high-rise building evacuation processes in future.展开更多
Wireless sensor networks are suffering from serious frequency interference.In this paper,we propose a channel assignment algorithm based on graph theory in wireless sensor networks.We first model the conflict infectio...Wireless sensor networks are suffering from serious frequency interference.In this paper,we propose a channel assignment algorithm based on graph theory in wireless sensor networks.We first model the conflict infection graph for channel assignment with the goal of global optimization minimizing the total interferences in wireless sensor networks.The channel assignment problem is equivalent to the generalized graph-coloring problem which is a NP-complete problem.We further present a meta-heuristic Wireless Sensor Network Parallel Tabu Search(WSN-PTS) algorithm,which can optimize global networks with small numbers of iterations.The results from a simulation experiment reveal that the novel algorithm can effectively solve the channel assignment problem.展开更多
This paper describes a broad perspective of the application of graph theory to establishment of GPS control networks whereby the GPS network is considered as a connected and directed graph with three components.In thi...This paper describes a broad perspective of the application of graph theory to establishment of GPS control networks whereby the GPS network is considered as a connected and directed graph with three components.In this algorithm the gross error detection is undertaken through loops of different spanning trees using the "Loop Law" in which the individual components Δ X, Δ Y and Δ Z sum up to zero.If the sum of the respective vector components ∑X,∑Y and ∑Z in a loop is not zero and if the error is beyond the tolerable limit (ε>w),it indicates the existence of gross errors in one of the baselines in the loop and therefore the baseline must be removed or re_observed.After successful screening of errors by graph theory,network adjustment can be carried out.In this paper,the GPS data from the control network established as reference system for the HP Dam at Baishan county in Liaoning province is presented to illustrate the algorithm.展开更多
Multi-body dynamics,relative coordinates and graph theory are combined to analyze the structure of a vehicle suspension.The dynamic equations of the left front suspension system are derived for modeling.First,The pure...Multi-body dynamics,relative coordinates and graph theory are combined to analyze the structure of a vehicle suspension.The dynamic equations of the left front suspension system are derived for modeling.First,The pure tire theory model is used as the input criteria of the suspension multibody system dynamic model in order to simulate the suspension K&C characteristics test.Then,it is important to verify the accuracy of this model by comparing and analyzing the experimental data and simulation results.The results show that the model has high precision and can predict the performance of the vehicle.It also provides a new solution for the vehicle dynamic modeling.展开更多
This paper studies an interference coordination method by means of spectrum allocation in Long-Term Evolution (LTE) multi-cell scenario that comprises of macrocells and femtocells. The purpose is to maximize the total...This paper studies an interference coordination method by means of spectrum allocation in Long-Term Evolution (LTE) multi-cell scenario that comprises of macrocells and femtocells. The purpose is to maximize the total throughput of femtocells while ensuring the Signal-to-Interference plus Noise Ratio (SINR) of the edge macro mobile stations (mMSs) and the edge femtocell Mobile Stations (fMSs). A new spectrum allocation algorithm based on graph theory is proposed to reduce the interference. Firstly, the ratio of Resource Blocks (RBs) that mMSs occupy is obtained by genetic algorithm. Then, after considering the impact of the macro Base Stations (mBSs) and small scale fading to the fMS on different RBs, multi-interference graphs are established and the spectrum is allocated dynamically. The simulation results show that the proposed algorithm can meet the Quality of Service (QoS) requirements of the mMSs. It can strike a balance between the edge fMSs' throughput and the whole fMSs' throughput.展开更多
We develop a new geometric approach to deal with qubit information systems using colored graph theory. More precisely, we present a one to one correspondence between graph theory, and qubit systems, which may be explo...We develop a new geometric approach to deal with qubit information systems using colored graph theory. More precisely, we present a one to one correspondence between graph theory, and qubit systems, which may be explored to attack qubit information problems using torie geometry considered as a powerful tool to understand modern physics including string theory. Concretely, we examine in some details the cases of one, two, and three qubits, and we find that they are associated with CP1, CP1×CP1 and CP1×CP1× CP1 toric varieties respectively. Using a geometric procedure referred to as a colored toric geometry, we show that the qubit physics can be converted into a scenario handling toric data of such manifolds by help of hypercube graph theory. Operations on toric information can produce universal quantum gates.展开更多
Limit equilibrium method （LEM） and strength reduction method （SRM） are the most widely used methods for slope stability analysis. However, it can be noted that they both have some limitations in practical applicat...Limit equilibrium method （LEM） and strength reduction method （SRM） are the most widely used methods for slope stability analysis. However, it can be noted that they both have some limitations in practical application. In the LEM, the constitutive model cannot be considered and many assumptions are needed between slices of soil/rock. The SRM requires iterative calculations and does not give the slip surface directly. A method for slope stability analysis based on the graph theory is recently developed to directly calculate the minimum safety factor and potential critical slip surface according to the stress results of numerical simulation. The method is based on current stress state and can overcome the disadvantages mentioned above in the two traditional methods. The influences of edge generation and mesh geometry on the position of slip surface and the safety factor of slope are studied, in which a new method for edge generation is proposed, and reasonable mesh size is suggested. The results of benchmark examples and a rock slope show good accuracy and efficiency of the presented method.展开更多
Material exchange frequently occurs in gullies,and thus the relationship between a gullynetwork structure and sediment transport potential has attracted considerable interest.However,previous researches ignored the di...Material exchange frequently occurs in gullies,and thus the relationship between a gullynetwork structure and sediment transport potential has attracted considerable interest.However,previous researches ignored the difficulty of material transport from sources to sinks,and did not quantify the connectivity of a network structure.In this study,we used a graph model structure to model gully networks of six typical sample areas in the Loess Plateau of China and quantified gully network connectivity using four indexes:average node strength,accessibility from sources to sinks,potential flow,and network structural connectivity index.Results show that:(1)Reflected by different quantitative indexes,the trends of gully network connectivity in different regions are similar.From north to south,the connectivity of a sample area first increases and then decreases.(2)The more mature gullies have stronger network connectivity.Small resistance is conducive to material transport in the gullies.(3)The node connectivity index of the gully network shows a significant aggregation distribution in space,and node connectivity on the main channel is often stronger than that on the branch trench.These results not only deepen the understanding of the process and mechanism of loess gully geomorphic development and evolution but also provide a reference for geomorphic studies.展开更多
One of the hot research topics in propagation dynamics is identifying a set of critical nodes that can influence maximization in a complex network.The importance and dispersion of critical nodes among them are both vi...One of the hot research topics in propagation dynamics is identifying a set of critical nodes that can influence maximization in a complex network.The importance and dispersion of critical nodes among them are both vital factors that can influence maximization.We therefore propose a multiple influential spreaders identification algorithm based on spectral graph theory.This algorithm first quantifies the role played by the local structure of nodes in the propagation process,then classifies the nodes based on the eigenvectors of the Laplace matrix,and finally selects a set of critical nodes by the constraint that nodes in the same class are not adjacent to each other while different classes of nodes can be adjacent to each other.Experimental results on real and synthetic networks show that our algorithm outperforms the state-of-the-art and classical algorithms in the SIR model.展开更多
Attacks on the cyber space is getting exponential in recent times.Illegal penetrations and breaches are real threats to the individuals and organizations.Conventional security systems are good enough to detect the kno...Attacks on the cyber space is getting exponential in recent times.Illegal penetrations and breaches are real threats to the individuals and organizations.Conventional security systems are good enough to detect the known threats but when it comes to Advanced Persistent Threats(APTs)they fails.These APTs are targeted,more sophisticated and very persistent and incorporates lot of evasive techniques to bypass the existing defenses.Hence,there is a need for an effective defense system that can achieve a complete reliance of security.To address the above-mentioned issues,this paper proposes a novel honeypot system that tracks the anonymous behavior of the APT threats.The key idea of honeypot leverages the concepts of graph theory to detect such targeted attacks.The proposed honey-pot is self-realizing,strategic assisted which withholds the APTs actionable tech-niques and observes the behavior for analysis and modelling.The proposed graph theory based self learning honeypot using the resultsγ(C(n,1)),γc(C(n,1)),γsc(C(n,1))outperforms traditional techniques by detecting APTs behavioral with detection rate of 96%.展开更多
A graph theory model of the human nature structure( GMH) for machine vision and image/graphics processing is described in this paper. Independent from the motion and deformation of contours,the human nature structure(...A graph theory model of the human nature structure( GMH) for machine vision and image/graphics processing is described in this paper. Independent from the motion and deformation of contours,the human nature structure( HNS) embodies the most basic movement characteristics of the body. The human body can be divided into basic units like head,torso,and limbs. Using these basic units,a graph theory model for the HNS can be constructed. GMH provides a basic model for human posture processing,and the outline in the perspective projection plane is the body contour of an image. In addition,the GMH can be applied to articulated motion and deformable objects,e. g.,in the design and analysis of body posture,by modifying mapping parameters of the GMH.展开更多
Total Knee Replacement(TKR)is the increasing trend now a day,in revision surgery which is associated with aseptic loosening,which is a challenging research for the TKR component.The selection of optimal material loose...Total Knee Replacement(TKR)is the increasing trend now a day,in revision surgery which is associated with aseptic loosening,which is a challenging research for the TKR component.The selection of optimal material loosening can be controlled at some limits.This paper is going to consider the best material selected among a number of alternative materials for the femoral component(FC)by using Graph Theory.Here GTMA process used for optimization of material and a systematic technique introduced through sensitivity analysis to find out the more reliable result.Obtained ranking suggests the use of optimized material over the other existing material.By following GTMA Co_Cr-alloys(wrought-Co-Ni-Cr-Mo)and Co_Cr-alloys(cast-able-Co-Cr-Mo)are on the 1st and 2nd position respectively.展开更多
The primary purpose of this study is to present mathematical modeling methods inspired by graph theory operations and logic as a tool to structurally analyze the socio-economic composition of a city based on the geogr...The primary purpose of this study is to present mathematical modeling methods inspired by graph theory operations and logic as a tool to structurally analyze the socio-economic composition of a city based on the geographical lo-cation of the investigated areas.We’ve incorporated graph theory concepts like connectivity,subgraph,degree,tree,complete graph,and dual graph as our model’s main components.We applied these methods to study the geo-graphical distribution of food hardship in New York City,as well as housing prices in Boise,Idaho,and Miami,Florida.We conducted a structural analysis of our models and concluded several notable properties within the model results.We’ve also included the ocean’s current direction and location for the New York City model to speculate on the mechanism behind our results fur-ther.Graphs and quantitative data regarding each one of these factors are simulated and created through Gephi and R Studio,where the combination of these factors will be concluded and presented as the result of the study.In this way,the result of our model brings a step-by-step demonstration of how the graph theory and analysis techniques we’ve developed can be applied to any city with proper quantitative or qualitative data.The report in our pro-totype model focuses on population poverty and socio-economic conditions,emphasized and indicated through food hardship and the housing market within the area.We also discussed several plausible applications of our meth-ods,including topics like climate change and the real estate market.Consid-ering that our model is a skeletal position-based map exhibiting the func-tionality of the analysis techniques we’ve developed,the graph is a prototype for environmental science and mathematics researchers to examine,where they can further improve and optimize it for more accurate and informative results.展开更多
Origami mechanisms are extensively employed in various engineering applications due to their exceptional folding performance and deformability.The key to designing origami mechanisms lies in the design of the creases....Origami mechanisms are extensively employed in various engineering applications due to their exceptional folding performance and deformability.The key to designing origami mechanisms lies in the design of the creases.The crease design is often derived from experience and inspiration,so it is crucial to have a systematic approach to crease design.In this paper,a novel synthesis approach based on graph theory is proposed,which effectively addresses the challenge of designing the creases in origami mechanisms.The essence of this method lies in the acquisition of the double symmetrical crease pattern through the directed graph product operation of two subgraphs.The crease pattern can be simplified by employing a technique that eliminates certain creases while preserving the non-isomorphism and symmetry of the pattern.An improved mixed-integer linear programming model is developed to achieve an automatic distribution of the peak_valley creases of the origami.The proposed method ultimately generates 12 unique double symmetrical crease patterns.The new method proposed in this paper,through systematic design,significantly improves the efficiency of mechanism design while opening up broad prospects for exploring new mechanism structures,thereby greatly expanding its application potential in cutting-edge fields such as aerospace engineering and intelligent robots.展开更多
Graph theory has emerged as a valuable tool in liver research,aiding in the assessment of complex interactions underlying liver diseases at different organizational levels.This has allowed significant advancements in ...Graph theory has emerged as a valuable tool in liver research,aiding in the assessment of complex interactions underlying liver diseases at different organizational levels.This has allowed significant advancements in the detection,treatment,and control of liver disorders.Particularly,graph theory is useful in identifying different liver diseases.Graph theory can be used to analyze liver networks and identify altered nodes and edges,which may serve as potential noninvasive biomarkers for disease detection.Furthermore,graph-based techniques,including graph neural networks and graph knowledge,have been employed to construct interaction networks,providing insights into the communication involved in focal liver diseases and related conditions such as coronavirus disease 2019(COVID-19),hepatic muscular atrophy,and hepatic necrosis.Functional networks for the liver have also been developed with graphbased methods,providing insights into the metabolic processes occurring in the liver and the functional organization of the liver.Graph theory is also useful for image analysis,with applications such as image segmentation,registration,synthesis,and object identification.By representing images as graphs,it is possible to analyze and process them with graphbased algorithms,handling complex relationships among pixels and making them useful in boundary extraction and texture analysis.Overall,graph theory is an essential research tool for liver research,providing valuable insights into the complex interactions underlying liver diseases as well as innovative approaches for diagnosis and treatment.展开更多
The structure of water and proton transfer under nanoscale confinement has garnered significant attention due to its crucial role in elucidating various phenomena across multiple scientific disciplines.However,there r...The structure of water and proton transfer under nanoscale confinement has garnered significant attention due to its crucial role in elucidating various phenomena across multiple scientific disciplines.However,there remains a lack of consensus on fundamental properties such as diffusion behavior and the nature of hydrogen bonding in confined environments.In this work,we investigated the influence of confinement on proton transfer in water confined within graphene sheets at various spacings by ab initio molecule dynamic and multiscale analysis with time evolution of structural properties,graph theory and persistent homology.We found that reducing the graphene interlayer distance while maintaining water density close to that of bulk water leads to a decrease in proton transfer frequency.In contrast,reducing the interlayer distance without maintaining bulk-like water density results in an increase in proton transfer frequency.This difference is mainly due to the confinement conditions:when density is unchanged,the hydrogen bond network remains similar with significant layering,while compressive stress that increases density leads to a more planar hydrogen bond network,promoting faster proton transfer.Our findings elucidate the complex relationship between confinement and proton transfer dynamics,with implications for understanding proton transport in confined environments,relevant to energy storage and material design.展开更多
It is a challenge to determine the dominant topological characteristics of mechanical properties of adhesive interfaces.In this paper,we used graph theory and molecular dynamics simulation to investigate the influence...It is a challenge to determine the dominant topological characteristics of mechanical properties of adhesive interfaces.In this paper,we used graph theory and molecular dynamics simulation to investigate the influence of topological characteristics on the strength and toughness of highly cross-linked polymer interface systems.Based on the microstructure of the adhesive system,we extracted the dominant topological characteristics,including the connectivity degree(D)that determines the yield strength,and the average node-path(P)and the simple cycles proportions(R)that determine the deformability and load-bearing capacity during the void propagation respectively,which co-determine the toughness.The influence of the wall-effect on the dominant topological characteristics was also analyzed.The results showed that the interfacial yield strength increases with the increase of D,while the toughness increases with the increase of P and R.The wall-effect has a significant influence on D,P,and R.The strong wall-effect causes the enrichment of amino groups near the wall and insufficient cross-linking away from the wall,leading to the lower D and R,i.e.,the lower yield strength and load-bearing capacity during the void propagation.With the attenuation of the wall-effect,the D increases gradually,while the P and the R first increase and then decrease,showing an optimized wall-effect for the toughness of the adhesive interface.This paper reveals the dominant topological characteristics of adhesive interfacial strength and toughness,providing a new way to modulate the mechanical properties of polymer adhesive interface systems.展开更多
The theoretical challenges in understanding the nature of glass and glass transition raise significant questions in statistical and condensed matter physics.As a prototypical example of complex physical systems,glasse...The theoretical challenges in understanding the nature of glass and glass transition raise significant questions in statistical and condensed matter physics.As a prototypical example of complex physical systems,glasses and the vitrification process have been central research topics,consistently attracting broad scientific interest.This focus has driven extensive studies on phenomena such as aging,non-exponential relaxation,dynamic anomalies,glass-forming ability,and the mechanical response of glasses under stress.Recent advances in computational and experimental techniques have enabled rigorous testing of theoretical models,shedding new light on glass behavior.However,the intrinsic complexity of glass and the glass transition that lies in their physics,which spans multiple length and time scales,makes the system challenging to characterize.In this review,we emphasize the need to move beyond conventional approaches and propose a topological perspective as a promising alternative to address these challenges.Specifically,our findings reveal that the diversity in particle relaxation behavior is statistically linked to a global topological feature of the transient network structures formed by the particles in a given liquid.This direction offers opportunities to uncover novel phenomena that could fundamentally reshape our understanding of glassy materials.展开更多
文摘Optical transport networks are now the basic infrastructure of modern communications systems, including the SDH and WDM backbone network of local network operators, in the case of Cameroon. Given the colossal investments required to deploy these networks, particularly related to the cost of equipment (optical fibers, transponders and multiplexers), the optimization of bandwidth and dynamic allocation of resources is essential to control operating costs and ensure continuity of service. Automatic switching technology for optical networks brings intelligence to the control plane to fully facilitate bandwidth utilization, traffic redirection, and automatic configuration of end-to-end services. This paper considers a local network operator’s WDM network without the implementation of the automatic switching technology, develops a network modeling software platform called Graphic Networks and using graph theory integrates a particularity of the automatic switching technology, which is the automatic rerouting of traffic in case of incident in the network. The incidents considered here are those links or route failures and node failures.
文摘In this paper,different kinds of enzymes,immune factors and regulatory factors of the immune system of crustaceans are summarized and then combed systematically and thoroughly. According to the mutual influence and effects of these factors,different symbolic forms are introduced to express the effects,and ultimately the whole node graph of the system is obtained. The graph theory can be used for further researches on the immune system of crustacean.
基金supported by Beijing University of Civil Engineering and Architecture Nature Science(ZF16078,X18067)
文摘It is difficult to rescue people from outside, and emergency evacuation is still a main measure to decrease casualties in high-rise building fires. To improve evacuation efficiency, a valid and easily manipulated grouping evacuation strategy is proposed. Occupants escape in groups according to the shortest evacuation route is determined by graph theory. In order to evaluate and find the optimal grouping, computational experiments are performed to design and simulate the evacuation processes. A case study shown the application in detail and quantitative research conclusions is obtained. The thoughts and approaches of this study can be used to guide actual high-rise building evacuation processes in future.
基金supported by National Key Basic Research Program of China(973 program) under Grant No. 2007CB307101National Natural Science Foundation of China under Grant No.60833002,No.60802016,No.60972010+1 种基金Next Generation Internet of China under Grant No.CNGI-0903-05the Fundamental Research Funds for the Central Universities under Grant No.2009YJS011
文摘Wireless sensor networks are suffering from serious frequency interference.In this paper,we propose a channel assignment algorithm based on graph theory in wireless sensor networks.We first model the conflict infection graph for channel assignment with the goal of global optimization minimizing the total interferences in wireless sensor networks.The channel assignment problem is equivalent to the generalized graph-coloring problem which is a NP-complete problem.We further present a meta-heuristic Wireless Sensor Network Parallel Tabu Search(WSN-PTS) algorithm,which can optimize global networks with small numbers of iterations.The results from a simulation experiment reveal that the novel algorithm can effectively solve the channel assignment problem.
文摘This paper describes a broad perspective of the application of graph theory to establishment of GPS control networks whereby the GPS network is considered as a connected and directed graph with three components.In this algorithm the gross error detection is undertaken through loops of different spanning trees using the "Loop Law" in which the individual components Δ X, Δ Y and Δ Z sum up to zero.If the sum of the respective vector components ∑X,∑Y and ∑Z in a loop is not zero and if the error is beyond the tolerable limit (ε>w),it indicates the existence of gross errors in one of the baselines in the loop and therefore the baseline must be removed or re_observed.After successful screening of errors by graph theory,network adjustment can be carried out.In this paper,the GPS data from the control network established as reference system for the HP Dam at Baishan county in Liaoning province is presented to illustrate the algorithm.
基金Supported by the National Key Research and Development Program of China(2017YFB0103801)
文摘Multi-body dynamics,relative coordinates and graph theory are combined to analyze the structure of a vehicle suspension.The dynamic equations of the left front suspension system are derived for modeling.First,The pure tire theory model is used as the input criteria of the suspension multibody system dynamic model in order to simulate the suspension K&C characteristics test.Then,it is important to verify the accuracy of this model by comparing and analyzing the experimental data and simulation results.The results show that the model has high precision and can predict the performance of the vehicle.It also provides a new solution for the vehicle dynamic modeling.
基金Supported by National Natural Science Foundation of China (61171094, 61071092)National Science & Technology Key Project (2011ZX03001-006-02, 2011ZX03005-004-03)Key Project of Jiangsu Provincial Natural Science Foundation (BK2011027)
文摘This paper studies an interference coordination method by means of spectrum allocation in Long-Term Evolution (LTE) multi-cell scenario that comprises of macrocells and femtocells. The purpose is to maximize the total throughput of femtocells while ensuring the Signal-to-Interference plus Noise Ratio (SINR) of the edge macro mobile stations (mMSs) and the edge femtocell Mobile Stations (fMSs). A new spectrum allocation algorithm based on graph theory is proposed to reduce the interference. Firstly, the ratio of Resource Blocks (RBs) that mMSs occupy is obtained by genetic algorithm. Then, after considering the impact of the macro Base Stations (mBSs) and small scale fading to the fMS on different RBs, multi-interference graphs are established and the spectrum is allocated dynamically. The simulation results show that the proposed algorithm can meet the Quality of Service (QoS) requirements of the mMSs. It can strike a balance between the edge fMSs' throughput and the whole fMSs' throughput.
文摘We develop a new geometric approach to deal with qubit information systems using colored graph theory. More precisely, we present a one to one correspondence between graph theory, and qubit systems, which may be explored to attack qubit information problems using torie geometry considered as a powerful tool to understand modern physics including string theory. Concretely, we examine in some details the cases of one, two, and three qubits, and we find that they are associated with CP1, CP1×CP1 and CP1×CP1× CP1 toric varieties respectively. Using a geometric procedure referred to as a colored toric geometry, we show that the qubit physics can be converted into a scenario handling toric data of such manifolds by help of hypercube graph theory. Operations on toric information can produce universal quantum gates.
基金support of the National Natural Science Foundation of China (Grant No. 41130751)China Scholarship Council, Research Program for Western China Communication (Grant No. 2011ZB04)China Central University Funding
文摘Limit equilibrium method （LEM） and strength reduction method （SRM） are the most widely used methods for slope stability analysis. However, it can be noted that they both have some limitations in practical application. In the LEM, the constitutive model cannot be considered and many assumptions are needed between slices of soil/rock. The SRM requires iterative calculations and does not give the slip surface directly. A method for slope stability analysis based on the graph theory is recently developed to directly calculate the minimum safety factor and potential critical slip surface according to the stress results of numerical simulation. The method is based on current stress state and can overcome the disadvantages mentioned above in the two traditional methods. The influences of edge generation and mesh geometry on the position of slip surface and the safety factor of slope are studied, in which a new method for edge generation is proposed, and reasonable mesh size is suggested. The results of benchmark examples and a rock slope show good accuracy and efficiency of the presented method.
基金supported by the National Natural Science Foundation of China(Grant Nos.42271421 and 41930102)。
文摘Material exchange frequently occurs in gullies,and thus the relationship between a gullynetwork structure and sediment transport potential has attracted considerable interest.However,previous researches ignored the difficulty of material transport from sources to sinks,and did not quantify the connectivity of a network structure.In this study,we used a graph model structure to model gully networks of six typical sample areas in the Loess Plateau of China and quantified gully network connectivity using four indexes:average node strength,accessibility from sources to sinks,potential flow,and network structural connectivity index.Results show that:(1)Reflected by different quantitative indexes,the trends of gully network connectivity in different regions are similar.From north to south,the connectivity of a sample area first increases and then decreases.(2)The more mature gullies have stronger network connectivity.Small resistance is conducive to material transport in the gullies.(3)The node connectivity index of the gully network shows a significant aggregation distribution in space,and node connectivity on the main channel is often stronger than that on the branch trench.These results not only deepen the understanding of the process and mechanism of loess gully geomorphic development and evolution but also provide a reference for geomorphic studies.
基金the National Natural Science Foundation of China(Grant No.62176217)the Program from the Sichuan Provincial Science and Technology,China(Grant No.2018RZ0081)the Fundamental Research Funds of China West Normal University(Grant No.17E063)。
文摘One of the hot research topics in propagation dynamics is identifying a set of critical nodes that can influence maximization in a complex network.The importance and dispersion of critical nodes among them are both vital factors that can influence maximization.We therefore propose a multiple influential spreaders identification algorithm based on spectral graph theory.This algorithm first quantifies the role played by the local structure of nodes in the propagation process,then classifies the nodes based on the eigenvectors of the Laplace matrix,and finally selects a set of critical nodes by the constraint that nodes in the same class are not adjacent to each other while different classes of nodes can be adjacent to each other.Experimental results on real and synthetic networks show that our algorithm outperforms the state-of-the-art and classical algorithms in the SIR model.
文摘Attacks on the cyber space is getting exponential in recent times.Illegal penetrations and breaches are real threats to the individuals and organizations.Conventional security systems are good enough to detect the known threats but when it comes to Advanced Persistent Threats(APTs)they fails.These APTs are targeted,more sophisticated and very persistent and incorporates lot of evasive techniques to bypass the existing defenses.Hence,there is a need for an effective defense system that can achieve a complete reliance of security.To address the above-mentioned issues,this paper proposes a novel honeypot system that tracks the anonymous behavior of the APT threats.The key idea of honeypot leverages the concepts of graph theory to detect such targeted attacks.The proposed honey-pot is self-realizing,strategic assisted which withholds the APTs actionable tech-niques and observes the behavior for analysis and modelling.The proposed graph theory based self learning honeypot using the resultsγ(C(n,1)),γc(C(n,1)),γsc(C(n,1))outperforms traditional techniques by detecting APTs behavioral with detection rate of 96%.
基金Supported by the National Natural Science Foundation of China(No.71373023,61372148,61571045)Beijing Advanced Innovation Center for Imaging Technology(No.BAICIT-2016002)+1 种基金the National Key Technology R&D Program(No.2014BAK08B02,2015BAH55F03)the Importation and Development of High-Caliber Talents Project of Beijing Municipal Institutions(No.CIT&TCD201504039)
文摘A graph theory model of the human nature structure( GMH) for machine vision and image/graphics processing is described in this paper. Independent from the motion and deformation of contours,the human nature structure( HNS) embodies the most basic movement characteristics of the body. The human body can be divided into basic units like head,torso,and limbs. Using these basic units,a graph theory model for the HNS can be constructed. GMH provides a basic model for human posture processing,and the outline in the perspective projection plane is the body contour of an image. In addition,the GMH can be applied to articulated motion and deformable objects,e. g.,in the design and analysis of body posture,by modifying mapping parameters of the GMH.
文摘Total Knee Replacement(TKR)is the increasing trend now a day,in revision surgery which is associated with aseptic loosening,which is a challenging research for the TKR component.The selection of optimal material loosening can be controlled at some limits.This paper is going to consider the best material selected among a number of alternative materials for the femoral component(FC)by using Graph Theory.Here GTMA process used for optimization of material and a systematic technique introduced through sensitivity analysis to find out the more reliable result.Obtained ranking suggests the use of optimized material over the other existing material.By following GTMA Co_Cr-alloys(wrought-Co-Ni-Cr-Mo)and Co_Cr-alloys(cast-able-Co-Cr-Mo)are on the 1st and 2nd position respectively.
文摘The primary purpose of this study is to present mathematical modeling methods inspired by graph theory operations and logic as a tool to structurally analyze the socio-economic composition of a city based on the geographical lo-cation of the investigated areas.We’ve incorporated graph theory concepts like connectivity,subgraph,degree,tree,complete graph,and dual graph as our model’s main components.We applied these methods to study the geo-graphical distribution of food hardship in New York City,as well as housing prices in Boise,Idaho,and Miami,Florida.We conducted a structural analysis of our models and concluded several notable properties within the model results.We’ve also included the ocean’s current direction and location for the New York City model to speculate on the mechanism behind our results fur-ther.Graphs and quantitative data regarding each one of these factors are simulated and created through Gephi and R Studio,where the combination of these factors will be concluded and presented as the result of the study.In this way,the result of our model brings a step-by-step demonstration of how the graph theory and analysis techniques we’ve developed can be applied to any city with proper quantitative or qualitative data.The report in our pro-totype model focuses on population poverty and socio-economic conditions,emphasized and indicated through food hardship and the housing market within the area.We also discussed several plausible applications of our meth-ods,including topics like climate change and the real estate market.Consid-ering that our model is a skeletal position-based map exhibiting the func-tionality of the analysis techniques we’ve developed,the graph is a prototype for environmental science and mathematics researchers to examine,where they can further improve and optimize it for more accurate and informative results.
基金Supported by National Natural Science Foundation of China(Grant Nos.52375028,52205040)Hebei Provincial Natural Science Foundation(Grant Nos.E2024203052,E2024203105)Science and Technology Project of Hebei Education Department(Grant No.QN2023206).
文摘Origami mechanisms are extensively employed in various engineering applications due to their exceptional folding performance and deformability.The key to designing origami mechanisms lies in the design of the creases.The crease design is often derived from experience and inspiration,so it is crucial to have a systematic approach to crease design.In this paper,a novel synthesis approach based on graph theory is proposed,which effectively addresses the challenge of designing the creases in origami mechanisms.The essence of this method lies in the acquisition of the double symmetrical crease pattern through the directed graph product operation of two subgraphs.The crease pattern can be simplified by employing a technique that eliminates certain creases while preserving the non-isomorphism and symmetry of the pattern.An improved mixed-integer linear programming model is developed to achieve an automatic distribution of the peak_valley creases of the origami.The proposed method ultimately generates 12 unique double symmetrical crease patterns.The new method proposed in this paper,through systematic design,significantly improves the efficiency of mechanism design while opening up broad prospects for exploring new mechanism structures,thereby greatly expanding its application potential in cutting-edge fields such as aerospace engineering and intelligent robots.
基金Shanghai Municipal Science and Technology Major Project,Grant/Award Number:2023SHZD2X02A05Shanghai Rising-Star Program,Grant/Award Number:24QA2703300。
文摘Graph theory has emerged as a valuable tool in liver research,aiding in the assessment of complex interactions underlying liver diseases at different organizational levels.This has allowed significant advancements in the detection,treatment,and control of liver disorders.Particularly,graph theory is useful in identifying different liver diseases.Graph theory can be used to analyze liver networks and identify altered nodes and edges,which may serve as potential noninvasive biomarkers for disease detection.Furthermore,graph-based techniques,including graph neural networks and graph knowledge,have been employed to construct interaction networks,providing insights into the communication involved in focal liver diseases and related conditions such as coronavirus disease 2019(COVID-19),hepatic muscular atrophy,and hepatic necrosis.Functional networks for the liver have also been developed with graphbased methods,providing insights into the metabolic processes occurring in the liver and the functional organization of the liver.Graph theory is also useful for image analysis,with applications such as image segmentation,registration,synthesis,and object identification.By representing images as graphs,it is possible to analyze and process them with graphbased algorithms,handling complex relationships among pixels and making them useful in boundary extraction and texture analysis.Overall,graph theory is an essential research tool for liver research,providing valuable insights into the complex interactions underlying liver diseases as well as innovative approaches for diagnosis and treatment.
基金supported by the Natural Science Foundation of Xiamen,China(3502Z202472001)the National Natural Science Foundation of China(22402163,22021001,21925404,T2293692,and 22361132532).
文摘The structure of water and proton transfer under nanoscale confinement has garnered significant attention due to its crucial role in elucidating various phenomena across multiple scientific disciplines.However,there remains a lack of consensus on fundamental properties such as diffusion behavior and the nature of hydrogen bonding in confined environments.In this work,we investigated the influence of confinement on proton transfer in water confined within graphene sheets at various spacings by ab initio molecule dynamic and multiscale analysis with time evolution of structural properties,graph theory and persistent homology.We found that reducing the graphene interlayer distance while maintaining water density close to that of bulk water leads to a decrease in proton transfer frequency.In contrast,reducing the interlayer distance without maintaining bulk-like water density results in an increase in proton transfer frequency.This difference is mainly due to the confinement conditions:when density is unchanged,the hydrogen bond network remains similar with significant layering,while compressive stress that increases density leads to a more planar hydrogen bond network,promoting faster proton transfer.Our findings elucidate the complex relationship between confinement and proton transfer dynamics,with implications for understanding proton transport in confined environments,relevant to energy storage and material design.
基金supported by the National Key R&D Program of China(Grant No.2021YFA0719200)the National Natural Science Foundation of China(Grant Nos.12272391,12232020,and 11672314)the CAS Project for Young Scientists in Basic Research(Grant No.YSBR-096).
文摘It is a challenge to determine the dominant topological characteristics of mechanical properties of adhesive interfaces.In this paper,we used graph theory and molecular dynamics simulation to investigate the influence of topological characteristics on the strength and toughness of highly cross-linked polymer interface systems.Based on the microstructure of the adhesive system,we extracted the dominant topological characteristics,including the connectivity degree(D)that determines the yield strength,and the average node-path(P)and the simple cycles proportions(R)that determine the deformability and load-bearing capacity during the void propagation respectively,which co-determine the toughness.The influence of the wall-effect on the dominant topological characteristics was also analyzed.The results showed that the interfacial yield strength increases with the increase of D,while the toughness increases with the increase of P and R.The wall-effect has a significant influence on D,P,and R.The strong wall-effect causes the enrichment of amino groups near the wall and insufficient cross-linking away from the wall,leading to the lower D and R,i.e.,the lower yield strength and load-bearing capacity during the void propagation.With the attenuation of the wall-effect,the D increases gradually,while the P and the R first increase and then decrease,showing an optimized wall-effect for the toughness of the adhesive interface.This paper reveals the dominant topological characteristics of adhesive interfacial strength and toughness,providing a new way to modulate the mechanical properties of polymer adhesive interface systems.
基金supported by the National Natural Science Foundation of China(Grant Nos.12474184,52031016,11804027)。
文摘The theoretical challenges in understanding the nature of glass and glass transition raise significant questions in statistical and condensed matter physics.As a prototypical example of complex physical systems,glasses and the vitrification process have been central research topics,consistently attracting broad scientific interest.This focus has driven extensive studies on phenomena such as aging,non-exponential relaxation,dynamic anomalies,glass-forming ability,and the mechanical response of glasses under stress.Recent advances in computational and experimental techniques have enabled rigorous testing of theoretical models,shedding new light on glass behavior.However,the intrinsic complexity of glass and the glass transition that lies in their physics,which spans multiple length and time scales,makes the system challenging to characterize.In this review,we emphasize the need to move beyond conventional approaches and propose a topological perspective as a promising alternative to address these challenges.Specifically,our findings reveal that the diversity in particle relaxation behavior is statistically linked to a global topological feature of the transient network structures formed by the particles in a given liquid.This direction offers opportunities to uncover novel phenomena that could fundamentally reshape our understanding of glassy materials.
