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Prediction of Pediatric Sepsis Using a Deep Encoding Network with Cross Features
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作者 陈潇 张瑞 +1 位作者 汤心溢 钱娟 《Journal of Shanghai Jiaotong university(Science)》 EI 2024年第1期131-140,共10页
Sepsis poses a serious threat to health of children in pediatric intensive care unit.The mortality from pediatric sepsis can be effectively reduced through in-time diagnosis and therapeutic intervention.The bacillicul... Sepsis poses a serious threat to health of children in pediatric intensive care unit.The mortality from pediatric sepsis can be effectively reduced through in-time diagnosis and therapeutic intervention.The bacilliculture detection method is too time-consuming to receive timely treatment.In this research,we propose a new framework:a deep encoding network with cross features(CF-DEN)that enables accurate early detection of sepsis.Cross features are automatically constructed via the gradient boosting decision tree and distilled into the deep encoding network(DEN)we designed.The DEN is aimed at learning sufficiently effective representation from clinical test data.Each layer of the DEN fltrates the features involved in computation at current layer via attention mechanism and outputs the current prediction which is additive layer by layer to obtain the embedding feature at last layer.The framework takes the advantage of tree-based method and neural network method to extract effective representation from small clinical dataset and obtain accurate prediction in order to prompt patient to get timely treatment.We evaluate the performance of the framework on the dataset collected from Shanghai Children's Medical Center.Compared with common machine learning methods,our method achieves the increase on F1-score by 16.06%on the test set. 展开更多
关键词 pediatric sepsis gradient boosting decision tree cross feature neural network deep encoding network with cross features(CF-DEN)
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基于RIME优化VMD与TCN-Crossformer多尺度融合的短期电力负荷预测
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作者 黄宇 胡怡然 +3 位作者 马金杰 梁博彦 崔玉雷 张浩 《电力科学与工程》 2025年第8期48-57,共10页
针对电力负荷序列的多尺度非平稳性与跨维度动态关联特征导致的协同建模难题,提出了一种基于霜冰优化算法(Rime optimization algorithm,RIME)改进的变分模态分解(Variational mode decomposition,VMD)与时间卷积网络(Temporal convolut... 针对电力负荷序列的多尺度非平稳性与跨维度动态关联特征导致的协同建模难题,提出了一种基于霜冰优化算法(Rime optimization algorithm,RIME)改进的变分模态分解(Variational mode decomposition,VMD)与时间卷积网络(Temporal convolutional network,TCN)-Crossformer多尺度融合的预测模型。首先,利用RIME算法以样本熵均值为适应度函数,自适应优化VMD的惩罚系数与模态数,抑制模态混叠并提升分解质量;其次,通过TCN的因果卷积与膨胀卷积结构提取各模态分量的局部时序波动特征,捕捉短期波动规律;最后,采用结合Crossformer的跨维度注意力机制,显式建模时间与特征维度的动态关联性,实现局部时序特征与全局依赖关系的多尺度协同融合。在南方某城市半小时级电力负荷数据集上的实验验证结果表明,相较于Informer等模型,所提模型的决定系数提升2.49%,平均绝对误差降低73.07%,且在四季预测中均表现出强鲁棒性。 展开更多
关键词 变分模态分解 跨维度注意力 RIME优化算法 时间卷积网络 crossformer
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Pattern dynamics of network-organized system with cross-diffusion
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作者 Qianqian Zheng Zhijie Wang Jianwei Shen 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第2期80-85,共6页
Cross-diffusion is a ubiquitous phenomenon in complex networks, but it is often neglected in the study of reaction–diffusion networks. In fact, network connections are often random. In this paper, we investigate patt... Cross-diffusion is a ubiquitous phenomenon in complex networks, but it is often neglected in the study of reaction–diffusion networks. In fact, network connections are often random. In this paper, we investigate pattern dynamics of random networks with cross-diffusion by using the method of network analysis and obtain a condition under which the network loses stability and Turing bifurcation occurs. In addition, we also derive the amplitude equation for the network and prove the stability of the amplitude equation which is also an effective tool to investigate pattern dynamics of the random network with cross diffusion. In the meantime, the pattern formation consistently matches the stability of the system and the amplitude equation is verified by simulations. A novel approach to the investigation of specific real systems was presented in this paper. Finally, the example and simulation used in this paper validate our theoretical results. 展开更多
关键词 cross diffusion random network Turing instability amplitude equation
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Novel Contiguous Cross Propagation Neural Network Built CAD for Lung Cancer
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作者 A.Alice Blessie P.Ramesh 《Computer Systems Science & Engineering》 SCIE EI 2023年第2期1467-1484,共18页
The present progress of visual-based detection of the diseased area of a malady plays an essential part in the medicalfield.In that case,the image proces-sing is performed to improve the image data,wherein it inhibits ... The present progress of visual-based detection of the diseased area of a malady plays an essential part in the medicalfield.In that case,the image proces-sing is performed to improve the image data,wherein it inhibits unintended dis-tortion of image features or it enhances further processing in various applications andfields.This helps to show better results especially for diagnosing diseases.Of late the early prediction of cancer is necessary to prevent disease-causing pro-blems.This work is proposed to identify lung cancer using lung computed tomo-graphy(CT)scan images.It helps to identify cancer cells’affected areas.In the present work,the original input image from Lung Image Database Consortium(LIDC)typically suffers from noise problems.To overcome this,the Gaborfilter used for image processing is highly enhanced.In the next stage,the Spherical Iterative Refinement Clustering(SIRC)algorithm identifies cancer-suspected areas on the CT scan image.This approach can help radiologists and medical experts recognize cancer diseases and syndromes so that serious progress can be avoided in the early stages.These new methods help to remove unwanted por-tions of the CT image and better utilization the image.The subspace extraction of features approach is beneficial for evaluating lung cancer.This paper introduces a novel approach called Contiguous Cross Propagation Neural Network that tends to locate regions afflicted by lung cancer using CT scan pictures(CCPNN).By using the feature values from the fourth step of the procedure,the proposed CCPNN tends to categorize the lesion in the lung nodular site.The efficiency of the suggested CCPNN approach is evaluated using classification metrics such as recall(%),precision(%),F-measure(percent),and accuracy(%).Finally,the incorrect classification ratios are determined to compare the trained networks’effectiveness,through these parameters of CCPNN,it obtains the outstanding per-formance of 98.06%and it has provided the lowest false ratio of 1.8%. 展开更多
关键词 Contiguous cross propagation neural network(CCPNN) Gaborfilter
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Formal Description of the Crossing Social Network System Architecture Based on Temporal Logic
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作者 XIAO Ruliang NI Youcong +1 位作者 DU xin GONG Ping 《Wuhan University Journal of Natural Sciences》 CAS 2011年第6期525-534,共10页
How to organize crossing social network resources on a higher level of integration and address them to users' desktops is an important difficult problem. Especially, there is a lack of efficient approaches to softwar... How to organize crossing social network resources on a higher level of integration and address them to users' desktops is an important difficult problem. Especially, there is a lack of efficient approaches to software architecture to build reusable system over the crossing social network, From the viewpoint of temporal logic XYZ/E, this paper proposes a kind of Architecture Descrip- tion Language about the Crossing Social Network system (CSN_ADL), which can be used to depict the main key processes over the cross-social network system, and formally defines some key concepts, such as relation component, corelation component, override corelation connector, interaction connector, corelation network-oriented architecture, as well as system correctness, system activity, and system safety. Furthermore, some properties of correctness, activity, and safety under the flame CSN_ADL is discussed and depicted formally, which provides a formally theo- retical instruction for architecture reuses. 展开更多
关键词 cross-social network architecture description language corelation ACTIVITY
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Coupled Cross-correlation Neural Network Algorithm for Principal Singular Triplet Extraction of a Cross-covariance Matrix 被引量:2
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作者 Xiaowei Feng Xiangyu Kong Hongguang Ma 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第2期149-156,共8页
This paper proposes a novel coupled neural network learning algorithm to extract the principal singular triplet (PST) of a cross-correlation matrix between two high-dimensional data streams. We firstly introduce a nov... This paper proposes a novel coupled neural network learning algorithm to extract the principal singular triplet (PST) of a cross-correlation matrix between two high-dimensional data streams. We firstly introduce a novel information criterion (NIC), in which the stationary points are singular triplet of the crosscorrelation matrix. Then, based on Newton's method, we obtain a coupled system of ordinary differential equations (ODEs) from the NIC. The ODEs have the same equilibria as the gradient of NIC, however, only the first PST of the system is stable (which is also the desired solution), and all others are (unstable) saddle points. Based on the system, we finally obtain a fast and stable algorithm for PST extraction. The proposed algorithm can solve the speed-stability problem that plagues most noncoupled learning rules. Moreover, the proposed algorithm can also be used to extract multiple PSTs effectively by using sequential method. © 2014 Chinese Association of Automation. 展开更多
关键词 Clustering algorithms Covariance matrix Data mining Differential equations EXTRACTION Learning algorithms Negative impedance converters Newton Raphson method Ordinary differential equations Singular value decomposition
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A CROSS-LAYER STRATEGY FOR COOPERATIVE DIVERSITY IN WIRELESS SENSOR NETWORKS 被引量:1
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作者 ChenYongrui YangYang YiWeidong 《Journal of Electronics(China)》 2012年第1期33-38,共6页
We investigate the problem of how to minimize the energy consumption in multi-hop Wireless Sensor Network (WSN),under the constraint of end-to-end reliability Quality of Seervice (QoS) requirement.Based on the investi... We investigate the problem of how to minimize the energy consumption in multi-hop Wireless Sensor Network (WSN),under the constraint of end-to-end reliability Quality of Seervice (QoS) requirement.Based on the investigation,we jointly consider the routing,relay selection and power allocation algorithm,and present a novel distributed cross-layer strategy using opportunistic relaying scheme for cooperative communication.The results show that under the same QoS requirement,the proposed cross-layer strategy performs better than other cross-layer cooperative communication algorithms in energy efficiency.We also investigated the impact of several parameters on the energy efficiency of the cooperative communication in WSNs,thus can be used to provide guidelines to decide when and how to apply cooperation for a given setup. 展开更多
关键词 Wireless Sensor network (WSN) cross-layer design Cooperative diversity Opportun-istic relaying
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Cross-layer Enhancement to Multi-hop Routing in Sensor Networks: an Empirical Study
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作者 SHANG Zhi-Jun WANG Jun YU Hai-Bin 《自动化学报》 EI CSCD 北大核心 2006年第6期875-880,共6页
Lossy link is one of the unique characteristics in random-deployed sensor networks. We envision that robustness and reliability of routing cannot be ensured purely in network layer. Our idea is to enhance the performa... Lossy link is one of the unique characteristics in random-deployed sensor networks. We envision that robustness and reliability of routing cannot be ensured purely in network layer. Our idea is to enhance the performance of routing protocol by cross-layer interaction. We modified mint protocol, a routing protocol in TinyOS and proposed an enhanced version of mint called PA-mint. A transmission power control interface is added to network layer in PA-mint. When routing performance of the current network is not satisfied, PA-mint monotonically increases the transmission power via the interface we added. PA-mint is able to connect orphan nodes and robust to node mobility or key nodes failure. In the case that automatic request retransmission is employed, the number of retransmissions can be reduced by PA-mint. Results from experiments show that PA-mint increases the reliability and robustness of routing protocol by cross-layer interaction. 展开更多
关键词 Sensor networks ROUTING cross-layer design
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An Energy-Efficient Access Control Algorithm with Cross-Layer Optimization in Wireless Sensor Networks 被引量:1
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作者 Zhi Chen Shaoqian Li 《Wireless Sensor Network》 2010年第2期168-172,共5页
This paper presents a wireless sensor network (WSN) access control algorithm designed to minimize WSN node energy consumption. Based on slotted ALOHA protocol, this algorithm incorporates the power control of physical... This paper presents a wireless sensor network (WSN) access control algorithm designed to minimize WSN node energy consumption. Based on slotted ALOHA protocol, this algorithm incorporates the power control of physical layer, the transmitting probability of medium access control (MAC) layer, and the automatic repeat request (ARQ) of link layer. In this algorithm, a cross-layer optimization is preformed to minimizing the energy consuming per bit. Through theory deducing, the transmitting probability and transmitting power level is determined, and the relationship between energy consuming per bit and throughput per node is provided. Analytical results show that the cross-layer algorithm results in a significant energy savings relative to layered design subject to the same throughput per node, and the energy saving is extraordinary in the low throughput region. 展开更多
关键词 Wireless Sensor network (WSN) cross-LAYER Design ENERGY Efficient ENERGY CONSUMPTION per Bit THROUGHPUT
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Cross Layer Design for Cooperative Transmission in Wireless Sensor Networks
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作者 Kanojia Sindhuben Babulal Rajiv Ranjan Tewari 《Wireless Sensor Network》 2011年第6期209-214,共6页
Several protocols and schemes have been proposed to reduce energy consumption in Wireless Sensor Net-works (WSNs). In this paper we employ farcoopt, a cross layer design approach with the concept of coop-eration among... Several protocols and schemes have been proposed to reduce energy consumption in Wireless Sensor Net-works (WSNs). In this paper we employ farcoopt, a cross layer design approach with the concept of coop-eration among the nodes with best farthest neighbor scheme to increase the Quality of Service (QoS), reduce energy consumption, increases performance and end-to-end throughput. We present cooperative transmission to connect previously disconnect parts of a network thus overcoming the separation problem of multi-hop network. We show that this approach improves connectivity over 50% compared to multi-hop approaches and reduces the number of nodes necessary to provide full coverage of an area up to 35%. Simulation results show that on increase of data rates i.e. packet the network life time increases in farcoopt as compared to tra-ditional multi hop approach. The result of this analysis is presented in this work. 展开更多
关键词 COOPERATIVE network cross Layer Design WIRELESS Sensor networks Energy SAVING Communication PROTOCOL ROUTING
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Microporous Organic Nanotube Networks from Hyper Cross-linking Core-shell Bottlebrush Copolymers for Selective Adsorption Study 被引量:2
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作者 Tian-Qi Wang Yang Xu +2 位作者 Zi-Dong He Ming-Hong Zhou Kun Huang 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2018年第1期98-105,共8页
We report a synthesis of microporous organic nanotube networks(MONNs) by a combination of hyper cross-linking and molecular templating of core-shell bottlebrush copolymers. The intrabrush and interbrush cross-linkin... We report a synthesis of microporous organic nanotube networks(MONNs) by a combination of hyper cross-linking and molecular templating of core-shell bottlebrush copolymers. The intrabrush and interbrush cross-linking of polystyrene(PS) shell layer in the core-shell bottlebrush copolymers led to the formation of micropores and large-sized nanopores(meso/macrospores) in MONNs, respectively, while selective removal of polylactide(PLA) core layer generated mesoporous tubular structure. The size of PLA-templated mesoporous cores and porous structure both at micro-and meso-scale could be controlled by simple tuning of the ratio of core/shell or the PLA core fraction in the bottlebrush precursors. Moreover, the resultant MONNs showed a highly selective adsorption capacity for the positively charged dyes on the basis of multi-porosity and carboxylate group-rich structure. In addition, MONNs also exhibited effective performance in size-selective adsorption of biomacromolecules. This work represents a new avenue for the preparation of MONNs and also provides a new application for molecular bottlebrushes in nanotechnology. 展开更多
关键词 Microporous organic nanotube networks Hyper cross-linking Core-shell bottlebrush copolymers Meso/Macrospores Selective adsorption capacity
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A Cross-System Invocation Platform Based on Distributed Network Performance Measurement System
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作者 Zhenwen Xue Yuehui Jin Tan Yang 《International Journal of Communications, Network and System Sciences》 2016年第5期152-159,共8页
The Distributed Network Performance Measurement Sys-tem provides functions to derive performance indices of networks and services, which are significant for Network Management System. To make these two systems coopera... The Distributed Network Performance Measurement Sys-tem provides functions to derive performance indices of networks and services, which are significant for Network Management System. To make these two systems cooperate, we realize this cross-system invocation platform, using Web Service, a mechanism which allows two systems to exchange data over the internet through publishing interfaces [1]. There are several mature Web Service frameworks, Apache Axis2, Apache CXF etc. In this paper we choose Apache Axis2 to achieve the objective that the Network Management System can invocate the net-work performance measurement functions via the Web Services. 展开更多
关键词 network Measurement cross-System Web Service Apache Axis2
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新兴技术跨界融合下多层网络形成及演化研究 被引量:4
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作者 曹兴 赵凤雅 赵倩可 《科学学研究》 北大核心 2025年第4期751-762,共12页
新一轮科技革命呈现出多领域、跨学科和群体性突破等新的特征,创新主体通过跨越技术、组织等边界,吸收、整合异质性创新资源,实现技术间的融合,并在技术领域交叉处涌现出创新点,推动了新兴技术跨界创新的形成。通过分析技术跨界融合和... 新一轮科技革命呈现出多领域、跨学科和群体性突破等新的特征,创新主体通过跨越技术、组织等边界,吸收、整合异质性创新资源,实现技术间的融合,并在技术领域交叉处涌现出创新点,推动了新兴技术跨界创新的形成。通过分析技术跨界融合和创新主体跨界合作,构建了合作子网络、技术子网络及辅助子网络的新兴技术跨界融合网络,深入分析新兴技术跨界融合机理,以5G技术和人工智能(AI)技术的跨界融合为研究对象,运用专利数据对新兴技术跨界融合网络进行了实证分析。研究发现:随着5G技术和AI技术的跨界融合,创新主体和技术领域的数量增加,创新主体间的合作关系趋于稳定;技术领域间的融合程度增加,创新主体跨界合作、技术跨界融合的广度和深度增加;高校和科技型企业是推动5G技术和AI技术跨界融合的主力军;5G技术和AI技术跨界融合主要集中在电通信和计算等领域,加速推动了智能汽车等技术应用的发展。 展开更多
关键词 新兴技术 多层网络 跨界融合 网络演化
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双边市场网约车平台聚合策略选择研究 被引量:2
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作者 曹裕 李想 李青松 《中国管理科学》 北大核心 2025年第4期142-153,共12页
以网约车双边市场为背景,结合双边市场理论以及Hotelling模型构建双寡头平台竞争模型,分析一个由聚合平台中的小平台集合(A)与一个大平台(B)的竞争均衡,研究不同网络外部性强度与用户旅行成本的大平台聚合策略选择问题。理论推导了不聚... 以网约车双边市场为背景,结合双边市场理论以及Hotelling模型构建双寡头平台竞争模型,分析一个由聚合平台中的小平台集合(A)与一个大平台(B)的竞争均衡,研究不同网络外部性强度与用户旅行成本的大平台聚合策略选择问题。理论推导了不聚合策略(N)、跟随策略(F)与开放策略(O)下的双边市场规模决策、定价决策以及定价对用户转移的影响。进一步,通过数值模拟比较不同聚合策略下的大平台利润,发现交叉网络外部性与用户旅行成本是影响大平台聚合策略选择的重要因素。当用户端和司机端交叉网络外部性均低时,大平台不参与聚合,随着外部性上升,其选择会从跟随策略转变为开放策略,其中用户端网络外部性对跟随策略、司机端网络外部性对开放策略作用更为显著;当用户旅行成本低于阈值时,大平台采取跟随策略,否则不参与聚合。有趣的是,司机旅行成本和聚合平台抽成比例均不会影响大平台聚合策略选择,可为现实中聚合平台前期的免抽成策略做出解释。 展开更多
关键词 双边市场 网约车平台 聚合策略 交叉网络外部性
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Cross Layered MAC Design for RF Energy Harvesting Sensor Network
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作者 Thangavelu Sasikala Veerasamy Jawahar Senthil Kumar 《Circuits and Systems》 2016年第9期2676-2688,共13页
The main research objective in wireless sensor networks (WSN) domain is to develop algorithms and protocols to ensure minimal energy consumption with maximum network lifetime. In this paper, we propose a novel design ... The main research objective in wireless sensor networks (WSN) domain is to develop algorithms and protocols to ensure minimal energy consumption with maximum network lifetime. In this paper, we propose a novel design for energy harvesting sensor node and cross-layered MAC protocol using three adjacent layers (Physical, MAC and Network) to economize energy for WSN. The basic idea behind our protocol is to re-energize the neighboring nodes using the radio frequency (RF) energy transmitted by the active nodes. This can be achieved by designing new energy harvesting sensor node and redesigning the MAC protocol. The results show that the proposed cross layer CL_EHSN improves the life time of the WSN by 40%. 展开更多
关键词 Wireless Sensor network cross Layer Design RF Energy Harvesting Lifetime Enhancement
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Performance Study of a Cross-Layer Based Multipath Routing Protocol for IEEE 802.11e Mobile Ad Hoc Networks
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作者 Hang SHEN Guangwei BAI +2 位作者 Junyuan WANG Yong JIN Jinjing TAO 《International Journal of Communications, Network and System Sciences》 2008年第4期329-338,共10页
Communication over wireless links identifies significant challenges for routing protocols operating. This paper proposes a Cross-layer design based Multipath Routing Protocol (CMRP) for mobile ad hoc networks, by mean... Communication over wireless links identifies significant challenges for routing protocols operating. This paper proposes a Cross-layer design based Multipath Routing Protocol (CMRP) for mobile ad hoc networks, by means of the node energy signal from the physical layer. The purpose is to optimize routing decision and path quality. The nodes’ mobility behavior is predicted using a notion of “Signal Fading Degree, SFD”. Especially, in combination of the IEEE 802.11e standard at the MAC layer, we determine that the IEEE 802.11e makes a significant contribution to performance improvement of CMRP. Performance evaluation of AODV in legacy 802.11 and CMRP in IEEE 802.11e shows that, as a function of speed of node mobility, a tremendous reduction achieved, in metrics such as the average end-to-end delay, route overhead, route discovery frequency, normalized routing load - almost more than 80%, 40%, 40%, and 40%. In the case of varying number of sessions, the reduction for route discovery frequency and normalized routing load are up to 70% and 80%. 展开更多
关键词 Wireless Mobile Ad HOC networks MULTIPATH ROUTING cross-LAYER Design IEEE 802.11e
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海上无人系统跨域集群发展现状及其关键技术 被引量:3
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作者 闫敬 关新平 《自动化学报》 北大核心 2025年第4期744-761,共18页
随着无人系统技术的快速发展,海上无人系统跨域集群凭借其诸多优点已成为当前无人系统领域研究热点.具体来说,海上无人系统跨域集群是指空中、水面、水下无人平台,通过跨域任务规划与信息交互实现高效集群协作,对提升复杂海洋环境下无... 随着无人系统技术的快速发展,海上无人系统跨域集群凭借其诸多优点已成为当前无人系统领域研究热点.具体来说,海上无人系统跨域集群是指空中、水面、水下无人平台,通过跨域任务规划与信息交互实现高效集群协作,对提升复杂海洋环境下无人平台应对能力至关重要.目前,海上无人系统跨域集群理论体系还不完善,相关研究正面临诸多亟待解决的难题.为此,首先梳理跨域集群相关概念及其发展现状,分析其面临的挑战与关键问题;进而,从控制理论和通信技术相结合的角度出发,简述跨域集群任务规划、组网传输、协同控制等关键技术的研究进展;最后,结合实际发展情况和未来发展趋势,对海上无人系统跨域集群未来值得深入研究的方向进行总结与展望. 展开更多
关键词 集群 海上无人系统 跨域 协同控制 组网传输
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MA-CDMR:多域SDWN中一种基于多智能体深度强化学习的智能跨域组播路由方法 被引量:1
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作者 叶苗 胡洪文 +4 位作者 王勇 何倩 王晓丽 文鹏 郑基浩 《计算机学报》 北大核心 2025年第6期1417-1442,共26页
多域软件定义无线网络(SDWN)中的跨域组播路由问题不仅是NP难组合优化问题,随着网络规模的增加和组播组成员的动态变化,构建高效的跨域组播路由路径还需要及时灵活获取和维护全局网络状态信息并设计出最优跨域组播树问题的求解算法。针... 多域软件定义无线网络(SDWN)中的跨域组播路由问题不仅是NP难组合优化问题,随着网络规模的增加和组播组成员的动态变化,构建高效的跨域组播路由路径还需要及时灵活获取和维护全局网络状态信息并设计出最优跨域组播树问题的求解算法。针对现有求解方法对网络流量状态感知性能欠缺影响组播业务对QoS方面需求的满足,并且收敛速度慢难以适应网络状态高度动态变化的问题,本文设计和实现了一种基于多智能体深度强化学习的SDWN跨域组播路由方法(MA-CDMR)。首先,设计了组播组管理模块和多控制器之间的通信机制来实现不同域之间网络状态信息的传递和同步,有效管理跨域组播组成员的加入和离开;其次,在通过理论分析和证明最优跨域组播树包括最优的域间组播树和域内组播树两个部分的结论后,本文对每个控制器设计了一个智能体,并设计了这些多智能体之间的协作机制,以保证为跨域组播路由决策提供网络状态信息表示的一致性和有效性;然后,设计一种在线与离线相结合的多智能体强化学习训练方式,以减少对实时环境的依赖并加快多智能体收敛速度;最后,通过系列实验及其结果表明所提方法在不同网络链路信息状态下具有达到了很好的网络性能,平均瓶颈带宽相较于现有KMB、SCTF、DRL-M4MR和MADRL-MR方法分别提升了7.09%、46.01%、9.61%和10.11%;平均时延在与MADRL-MR方法表现相近的同时,相比KMB、SCTF和DRL-M4MR方法有明显提升,而丢包率和组播树平均长度等也均优于这些现有方法。本文工作源代码已提交至开源平台https://github.com/GuetYe/MA-CDMR。 展开更多
关键词 组播树 软件定义无线网络 跨域组播路由 多智能体 深度强化学习
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Performance Comparison of Vision Transformer- and CNN-Based Image Classification Using Cross Entropy: A Preliminary Application to Lung Cancer Discrimination from CT Images
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作者 Eri Matsuyama Haruyuki Watanabe Noriyuki Takahashi 《Journal of Biomedical Science and Engineering》 2024年第9期157-170,共14页
This study evaluates the performance and reliability of a vision transformer (ViT) compared to convolutional neural networks (CNNs) using the ResNet50 model in classifying lung cancer from CT images into four categori... This study evaluates the performance and reliability of a vision transformer (ViT) compared to convolutional neural networks (CNNs) using the ResNet50 model in classifying lung cancer from CT images into four categories: lung adenocarcinoma (LUAD), lung squamous cell carcinoma (LUSC), large cell carcinoma (LULC), and normal. Although CNNs have made significant advancements in medical imaging, their limited capacity to capture long-range dependencies has led to the exploration of ViTs, which leverage self-attention mechanisms for a more comprehensive global understanding of images. The study utilized a dataset of 748 lung CT images to train both models with standardized input sizes, assessing their performance through conventional metrics—accuracy, precision, recall, F1 score, specificity, and AUC—as well as cross entropy, a novel metric for evaluating prediction uncertainty. Both models achieved similar accuracy rates (95%), with ViT demonstrating a slight edge over ResNet50 in precision and F1 scores for specific classes. However, ResNet50 exhibited higher recall for LULC, indicating fewer missed cases. Cross entropy analysis showed that the ViT model had lower average uncertainty, particularly in the LUAD, Normal, and LUSC classes, compared to ResNet50. This finding suggests that ViT predictions are generally more reliable, though ResNet50 performed better for LULC. The study underscores that accuracy alone is insufficient for model comparison, as cross entropy offers deeper insights into the reliability and confidence of model predictions. The results highlight the importance of incorporating cross entropy alongside traditional metrics for a more comprehensive evaluation of deep learning models in medical image classification, providing a nuanced understanding of their performance and reliability. While the ViT outperformed the CNN-based ResNet50 in lung cancer classification based on cross-entropy values, the performance differences were minor and may not hold clinical significance. Therefore, it may be premature to consider replacing CNNs with ViTs in this specific application. 展开更多
关键词 Lung Cancer Classification Vision Transformers Convolutional Neural networks cross Entropy Deep Learning
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基于IDANN的跨工况齿轮箱故障诊断 被引量:1
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作者 赵玲 邹杰 +1 位作者 秦佳继 王航 《振动与冲击》 北大核心 2025年第9期282-289,共8页
迁移学习的方法在解决齿轮箱无监督故障诊断问题上取得了极大的进展。然而,由于齿轮箱数据分布差异、噪声和干扰以及模型的局限性影响,大多方法在面对复杂的齿轮箱数据集迁移效果不佳,同时对于网络输入的可解释性研究仍然很少。提出了... 迁移学习的方法在解决齿轮箱无监督故障诊断问题上取得了极大的进展。然而,由于齿轮箱数据分布差异、噪声和干扰以及模型的局限性影响,大多方法在面对复杂的齿轮箱数据集迁移效果不佳,同时对于网络输入的可解释性研究仍然很少。提出了一种改进的域对抗网络(improve domain-adversarial neural network, IDANN)。首先,使用改进的时频网络作为特征提取器,在信号输入网络的时候提供可解释性和降噪功能;然后,在域对抗网络中添加目标域的类级对齐方法,使用两个分类器来检测靠近决策边界的目标样本,以增强迁移性能。在东南大学齿轮箱和跨座式单轨齿轮箱数据集上验证了IDANN的有效性和可靠性,并在凯斯西储大学轴承数据集上测试IDANN在噪声条件下的性能,试验证明IDANN具有优秀的诊断性能和鲁棒性。 展开更多
关键词 迁移学习 可解释网络 跨工况故障诊断
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