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
As an essential tool for quantitative analysis of lower limb coordination,optical motion capture systems with marker-based encoding still suffer from inefficiency,high costs,spatial constraints,and the requirement for...As an essential tool for quantitative analysis of lower limb coordination,optical motion capture systems with marker-based encoding still suffer from inefficiency,high costs,spatial constraints,and the requirement for multiple markers.While 3D pose estimation algorithms combined with ordinary cameras offer an alternative,their accuracy often deteriorates under significant body occlusion.To address the challenge of insufficient 3D pose estimation precision in occluded scenarios—which hinders the quantitative analysis of athletes’lower-limb coordination—this paper proposes a multimodal training framework integrating spatiotemporal dependency networks with text-semantic guidance.Compared to traditional optical motion capture systems,this work achieves low-cost,high-precision motion parameter acquisition through the following innovations:(1)spatiotemporal dependency attention module is designed to establish dynamic spatiotemporal correlation graphs via cross-frame joint semantic matching,effectively resolving the feature fragmentation issue in existing methods.(2)noise-suppressed multi-scale temporal module is proposed,leveraging KL divergence-based information gain analysis for progressive feature filtering in long-range dependencies,reducing errors by 1.91 mm compared to conventional temporal convolutions.(3)text-pose contrastive learning paradigm is introduced for the first time,where BERT-generated action descriptions align semantic-geometric features via the BERT encoder,significantly enhancing robustness under severe occlusion(50%joint invisibility).On the Human3.6M dataset,the proposed method achieves an MPJPE of 56.21 mm under Protocol 1,outperforming the state-of-the-art baseline MHFormer by 3.3%.Extensive ablation studies on Human3.6M demonstrate the individual contributions of the core modules:the spatiotemporal dependency module and noise-suppressed multi-scale temporal module reduce MPJPE by 0.30 and 0.34 mm,respectively,while the multimodal training strategy further decreases MPJPE by 0.6 mm through text-skeleton contrastive learning.Comparative experiments involving 16 athletes show that the sagittal plane coupling angle measurements of hip-ankle joints differ by less than 1.2°from those obtained via traditional optical systems(two one-sided t-tests,p<0.05),validating real-world reliability.This study provides an AI-powered analytical solution for competitive sports training,serving as a viable alternative to specialized equipment.展开更多
This paper addresses a coordinated control problem for Spacecraft Formation Flying(SFF). The distributed followers are required to track and synchronize with the leader spacecraft.By using the feature points in the tw...This paper addresses a coordinated control problem for Spacecraft Formation Flying(SFF). The distributed followers are required to track and synchronize with the leader spacecraft.By using the feature points in the two-dimensional image space, an integrated 6-degree-of-freedom dynamic model is formulated for spacecraft relative motion. Without sophisticated threedimensional reconstruction, image features are directly utilized for the controller design. The proposed image-based controller can drive the follower spacecraft in the desired configuration with respect to the leader when the real-time captured images match their reference counterparts. To improve the precision of the formation configuration, the proposed controller employs a coordinated term to reduce the relative distance errors between followers. The uncertainties in the system dynamics are handled by integrating the adaptive technique into the controller, which increases the robustness of the SFF system. The closed-loop system stability is analyzed using the Lyapunov method and algebraic graph theory. A numerical simulation for a given SFF scenario is performed to evaluate the performance of the controller.展开更多
Femtocell is a promising technology for improving indoor coverage and offloading the macrocell.Femtocells tend to be densely deployed in populated areas such as the dormitories.However,the inter-tier interference seri...Femtocell is a promising technology for improving indoor coverage and offloading the macrocell.Femtocells tend to be densely deployed in populated areas such as the dormitories.However,the inter-tier interference seriously exists in the co-channel Densely Deployed Femtocell Network(DDFN).Since the Femtocell Access Points(FAPs) are randomly deployed by their customers,the interference cannot be predicted in advance.Meanwhile,new characteristics such as the short radius of femtocell and the small number of users lead to the inefficiency of the traditional frequency reuse algorithms such as Fractional Frequency Reuse(FFR).Aiming for the downlink interference coordination in the DDFN,in this paper,we propose a User-oriented Graph based Frequency Allocation(UGFA)algorithm.Firstly,we construct the interference graph for users in the network.Secondly,we study the conventional graph based resources allocation algorithm.Then an improved two steps graph based frequency allocation mechanism is proposed.Simulation results show that UGFA has a high frequency reuse ratio mean while guarantees a better throughput.展开更多
This paper reviews some main results and progress in distributed multi-agent coordination from a graph Laplacian perspective.Distributed multi-agent coordination has been a very active subject studied extensively by t...This paper reviews some main results and progress in distributed multi-agent coordination from a graph Laplacian perspective.Distributed multi-agent coordination has been a very active subject studied extensively by the systems and control community in last decades,including distributed consensus,formation control,sensor localization,distributed optimization,etc.The aim of this paper is to provide both a comprehensive survey of existing literature in distributed multi-agent coordination and a new perspective in terms of graph Laplacian to categorize the fundamental mechanisms for distributed coordination.For different types of graph Laplacians,we summarize their inherent coordination features and specific research issues.This paper also highlights several promising research directions along with some open problems that are deemed important for future study.展开更多
Government policy-group integration and policy-chain inference are significant to the execution of strategies in current Chinese society.Specifically,the coordination of hierarchical policies implemented among governm...Government policy-group integration and policy-chain inference are significant to the execution of strategies in current Chinese society.Specifically,the coordination of hierarchical policies implemented among government departments is one of the key challenges to rural revitalization.In recent years,various well-established quantitative methods have been proposed to evaluate policy coordination,but the majority of these relied on manual analysis,which can lead to subjective results.Thus,in this paper,a novel approach called“policy knowledge graph for the coordination among the government departments”(PG-CODE)is proposed,which incorporates topic modeling into policy knowledge graphs.Similar to a knowledge graph,a policy knowledge graph uses a graph-structured data model to integrate policy discourse.With latent Dirichlet allocation embedding,a policy knowledge graph could capture the underlying topics of the policies.Furthermore,coordination strength and topic diffusion among hierarchical departments could be inferred from the PG-CODE,as it can provide a better representation of coordination within the policy space.We implemented and evaluated the PG-CODE in the field of rural innovation and entrepreneurship policy,and the results effectively demonstrate improved coordination among departments.展开更多
We optimized the gradation of cold recycled mixture(CRM)based on low-temperature performance.Firstly,the low-temperature crack resistance of CRM with different gradation and emulsified asphalt content was studied by i...We optimized the gradation of cold recycled mixture(CRM)based on low-temperature performance.Firstly,the low-temperature crack resistance of CRM with different gradation and emulsified asphalt content was studied by indirect tension(IDT)and semi-circular bending(SCB)test.Thereafter,the low-temperature performance evaluation index suitable for CRM was put forward.Then,the triangular coordinate statistical chart was used to analyze the optimal proportion of three grades of aggregate which are 2.36-4.75 mm,0.075-2.36 mm and below 0.075 mm.The results showed that the W_(f) and G_(f) could distinguish the low-temperature performance of CRM with different mixtures and emulsified asphalt dosage.For cold recycled fine aggregate,2.36-4.75 mm,0.075-2.36 mm and less than 0.075 mm account for 20%-25%,74.3%-80%and 5%-8%,respectively.The CRM with lower void fraction,higher W_(f) and G_(f) could be obtained.Based on the reported findings,it was suggested that the sieve passing percentage of 4.75,2.36,and 0.075 mm of CRM is 45%-55%,27%-52%and 1.5%-5%,respectively.展开更多
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.
基金supported by the Major Sports Research Projects of Jiangsu Provincial Sports Bureau in 2022(No.ST221101).
文摘As an essential tool for quantitative analysis of lower limb coordination,optical motion capture systems with marker-based encoding still suffer from inefficiency,high costs,spatial constraints,and the requirement for multiple markers.While 3D pose estimation algorithms combined with ordinary cameras offer an alternative,their accuracy often deteriorates under significant body occlusion.To address the challenge of insufficient 3D pose estimation precision in occluded scenarios—which hinders the quantitative analysis of athletes’lower-limb coordination—this paper proposes a multimodal training framework integrating spatiotemporal dependency networks with text-semantic guidance.Compared to traditional optical motion capture systems,this work achieves low-cost,high-precision motion parameter acquisition through the following innovations:(1)spatiotemporal dependency attention module is designed to establish dynamic spatiotemporal correlation graphs via cross-frame joint semantic matching,effectively resolving the feature fragmentation issue in existing methods.(2)noise-suppressed multi-scale temporal module is proposed,leveraging KL divergence-based information gain analysis for progressive feature filtering in long-range dependencies,reducing errors by 1.91 mm compared to conventional temporal convolutions.(3)text-pose contrastive learning paradigm is introduced for the first time,where BERT-generated action descriptions align semantic-geometric features via the BERT encoder,significantly enhancing robustness under severe occlusion(50%joint invisibility).On the Human3.6M dataset,the proposed method achieves an MPJPE of 56.21 mm under Protocol 1,outperforming the state-of-the-art baseline MHFormer by 3.3%.Extensive ablation studies on Human3.6M demonstrate the individual contributions of the core modules:the spatiotemporal dependency module and noise-suppressed multi-scale temporal module reduce MPJPE by 0.30 and 0.34 mm,respectively,while the multimodal training strategy further decreases MPJPE by 0.6 mm through text-skeleton contrastive learning.Comparative experiments involving 16 athletes show that the sagittal plane coupling angle measurements of hip-ankle joints differ by less than 1.2°from those obtained via traditional optical systems(two one-sided t-tests,p<0.05),validating real-world reliability.This study provides an AI-powered analytical solution for competitive sports training,serving as a viable alternative to specialized equipment.
文摘This paper addresses a coordinated control problem for Spacecraft Formation Flying(SFF). The distributed followers are required to track and synchronize with the leader spacecraft.By using the feature points in the two-dimensional image space, an integrated 6-degree-of-freedom dynamic model is formulated for spacecraft relative motion. Without sophisticated threedimensional reconstruction, image features are directly utilized for the controller design. The proposed image-based controller can drive the follower spacecraft in the desired configuration with respect to the leader when the real-time captured images match their reference counterparts. To improve the precision of the formation configuration, the proposed controller employs a coordinated term to reduce the relative distance errors between followers. The uncertainties in the system dynamics are handled by integrating the adaptive technique into the controller, which increases the robustness of the SFF system. The closed-loop system stability is analyzed using the Lyapunov method and algebraic graph theory. A numerical simulation for a given SFF scenario is performed to evaluate the performance of the controller.
基金supported by the National Natural Science Foundation of China under Grant No.61372092the China National Science and Technology Major Projects on New Generation Broadband Wireless Mobile Communications Network under Grants No.2011ZX03005-004,No.2012ZX03001029-003,No.2012ZX03001008-003
文摘Femtocell is a promising technology for improving indoor coverage and offloading the macrocell.Femtocells tend to be densely deployed in populated areas such as the dormitories.However,the inter-tier interference seriously exists in the co-channel Densely Deployed Femtocell Network(DDFN).Since the Femtocell Access Points(FAPs) are randomly deployed by their customers,the interference cannot be predicted in advance.Meanwhile,new characteristics such as the short radius of femtocell and the small number of users lead to the inefficiency of the traditional frequency reuse algorithms such as Fractional Frequency Reuse(FFR).Aiming for the downlink interference coordination in the DDFN,in this paper,we propose a User-oriented Graph based Frequency Allocation(UGFA)algorithm.Firstly,we construct the interference graph for users in the network.Secondly,we study the conventional graph based resources allocation algorithm.Then an improved two steps graph based frequency allocation mechanism is proposed.Simulation results show that UGFA has a high frequency reuse ratio mean while guarantees a better throughput.
基金Project supported by the National Natural Science Foundation of China(No.61273113)
文摘This paper reviews some main results and progress in distributed multi-agent coordination from a graph Laplacian perspective.Distributed multi-agent coordination has been a very active subject studied extensively by the systems and control community in last decades,including distributed consensus,formation control,sensor localization,distributed optimization,etc.The aim of this paper is to provide both a comprehensive survey of existing literature in distributed multi-agent coordination and a new perspective in terms of graph Laplacian to categorize the fundamental mechanisms for distributed coordination.For different types of graph Laplacians,we summarize their inherent coordination features and specific research issues.This paper also highlights several promising research directions along with some open problems that are deemed important for future study.
基金supported by the National Social Science Fund of China(No.20BGL231)the Natural Science Foundation of Hubei Province(No.2018CFB380)。
文摘Government policy-group integration and policy-chain inference are significant to the execution of strategies in current Chinese society.Specifically,the coordination of hierarchical policies implemented among government departments is one of the key challenges to rural revitalization.In recent years,various well-established quantitative methods have been proposed to evaluate policy coordination,but the majority of these relied on manual analysis,which can lead to subjective results.Thus,in this paper,a novel approach called“policy knowledge graph for the coordination among the government departments”(PG-CODE)is proposed,which incorporates topic modeling into policy knowledge graphs.Similar to a knowledge graph,a policy knowledge graph uses a graph-structured data model to integrate policy discourse.With latent Dirichlet allocation embedding,a policy knowledge graph could capture the underlying topics of the policies.Furthermore,coordination strength and topic diffusion among hierarchical departments could be inferred from the PG-CODE,as it can provide a better representation of coordination within the policy space.We implemented and evaluated the PG-CODE in the field of rural innovation and entrepreneurship policy,and the results effectively demonstrate improved coordination among departments.
基金Funded by the Key Research and Development Plan of Jiangxi Province (No. 20223BBG74002)the Natural Science Foundation of China (Nos. 51778483, 51978521)the Fundamental Research Funds for the Central Universities (No. DUT24RC (3)100)。
文摘We optimized the gradation of cold recycled mixture(CRM)based on low-temperature performance.Firstly,the low-temperature crack resistance of CRM with different gradation and emulsified asphalt content was studied by indirect tension(IDT)and semi-circular bending(SCB)test.Thereafter,the low-temperature performance evaluation index suitable for CRM was put forward.Then,the triangular coordinate statistical chart was used to analyze the optimal proportion of three grades of aggregate which are 2.36-4.75 mm,0.075-2.36 mm and below 0.075 mm.The results showed that the W_(f) and G_(f) could distinguish the low-temperature performance of CRM with different mixtures and emulsified asphalt dosage.For cold recycled fine aggregate,2.36-4.75 mm,0.075-2.36 mm and less than 0.075 mm account for 20%-25%,74.3%-80%and 5%-8%,respectively.The CRM with lower void fraction,higher W_(f) and G_(f) could be obtained.Based on the reported findings,it was suggested that the sieve passing percentage of 4.75,2.36,and 0.075 mm of CRM is 45%-55%,27%-52%and 1.5%-5%,respectively.
