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Power Splitting Based SWIPT in Network-Coded Two-Way Networks with Data Rate Fairness:An Information-Theoretic Perspective 被引量:2
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作者 Ke Xiong Yu Zhang +1 位作者 Yueyun Chen Xiaofei Di 《China Communications》 SCIE CSCD 2016年第12期107-119,共13页
This paper investigates the simultaneous wireless information and powertransfer(SWIPT) for network-coded two-way relay network from an information-theoretic perspective, where two sources exchange information via an S... This paper investigates the simultaneous wireless information and powertransfer(SWIPT) for network-coded two-way relay network from an information-theoretic perspective, where two sources exchange information via an SWIPT-aware energy harvesting(EH) relay. We present a power splitting(PS)-based two-way relaying(PS-TWR) protocol by employing the PS receiver architecture. To explore the system sum rate limit with data rate fairness, an optimization problem under total power constraint is formulated. Then, some explicit solutions are derived for the problem. Numerical results show that due to the path loss effect on energy transfer, with the same total available power, PS-TWR losses some system performance compared with traditional non-EH two-way relaying, where at relatively low and relatively high signalto-noise ratio(SNR), the performance loss is relatively small. Another observation is that, in relatively high SNR regime, PS-TWR outperforms time switching-based two-way relaying(TS-TWR) while in relatively low SNR regime TS-TWR outperforms PS-TWR. It is also shown that with individual available power at the two sources, PS-TWR outperforms TS-TWR in both relatively low and high SNR regimes. 展开更多
关键词 two-way relay energy harvesting wireless power transfer data rate fairness network coding
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Performance analysis of a class of networked control systems under data rate constraints
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作者 李力雄 费敏锐 丁瑾 《Journal of Shanghai University(English Edition)》 2009年第5期356-358,共3页
In networked control system (NCS) where control loop is closed over communication network, limited data rate may deteriorate control performance even destabilize the control system. In this paper, performance analysis... In networked control system (NCS) where control loop is closed over communication network, limited data rate may deteriorate control performance even destabilize the control system. In this paper, performance analysis of a typical second-order control system with data rate constraints is conducted, and the concept of critical data rate (CDR) is presented. In order to find the CDR in NCS, an approximate searching method is proposed to guarantee acceptable control performance. 展开更多
关键词 networked control system (NCS) data rate network-induced delay performance of control
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A joint resource allocation strategy in a radar-communication coexistence network for target tracking and user serving
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作者 Haowei ZHANG Weijian LIU +3 位作者 Qun ZHANG Taiyong FEI Tao SONG Weike FENG 《Chinese Journal of Aeronautics》 2025年第5期350-376,共27页
With the rapid development of commercial communications,the research on Radar-Communication Coexistence(RCC)systems is becoming a hot spot.The resource allocation techniques play a crucial role in the RCC systems.A pe... With the rapid development of commercial communications,the research on Radar-Communication Coexistence(RCC)systems is becoming a hot spot.The resource allocation techniques play a crucial role in the RCC systems.A performance-driven Joint Radar-target and Communication-user Assignment,along with Power and Subchannel Allocation(JRCAPSA)strategy,is proposed for an RCC network.The optimization model aims to minimize the sum of weighted Bayesian Cramer-Rao Lower Bounds(BCRLBs)of target state estimates for radar purpose.This is subject to constraints such as the Communication Data Rate(CDR)for communication purpose,the total power budget in each RCC system,assignment relationships,and the number of available subchannels.Considering that such a problem falls into the realm of Mixed Integer Programming(MIP),a Three-stage Iteratively Augment-based Optimization Method(TIAOM)is developed.The Communication-User Assignment(CUA),Communication Subchannel Allocation(SCA),and Radar-Target Assignment(RTA)feasible solution domains are iteratively expanded based on their importance,leading to the efficient acquisition of a suboptimal solution.Simulation results show the outperformance of the proposed JRCAPSA strategy,compared to the other benchmarks and the OPTI toolbox.The results also imply that the Bayesian Cramer-Rao Lower Bound(BCRLB)is a more stringent optimization metric for the achieved Mean Square Error(MSE),compared to Mutual Information(MI)and Signal-to-Interference-Noise Ratio(SINR). 展开更多
关键词 Radar-communication coexistence Resource allocation Bayesian Cramer-Rao Lower Bound(BCRLB) Communication data rate(CDR) Convex optimization
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Low Data Overlab Rate Graph-Based SLAM with Distributed Submap Strategy 被引量:3
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作者 XIANGjiawei ZHANG Jinyi +1 位作者 WANG Bin MA Yongbin 《Journal of Shanghai Jiaotong university(Science)》 EI 2020年第5期650-658,共9页
Simultaneous localization and mapping(SLAM)is widely used in many robot applications to acquire the unknown environment's map and the robots location.Graph-based SLAM is demonstrated to be effective in large-scale... Simultaneous localization and mapping(SLAM)is widely used in many robot applications to acquire the unknown environment's map and the robots location.Graph-based SLAM is demonstrated to be effective in large-scale scenarios,and it intuitively performs the SLAM as a pose graph.But because of the high data overlap rate,traditional graph-based SLAM is not efficient in some respects,such as real time performance and memory usage.To reduce1 data overlap rate,a graph-based SLAM with distributed submap strategy(DSS)is presented.In its front-end,submap based scan matching is processed and loop closing detection is conducted.Moreover in its back-end,pose graph is updated for global optimization and submap merging.From a series of experiments,it is demonstrated that graph-based SLAM with DSS reduces 51.79%data overlap rate,decreases 39.70%runtime and 24.60%memory usage.The advantages over other low overlap rate method is also proved in runtime,memory usage,accuracy and robustness performance. 展开更多
关键词 graph-based SLAM distributed submap strategy data overlap rate
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Maximum Data Generation Rate Routing Protocol Based on Data Flow Controlling Technology for Rechargeable Wireless Sensor Networks 被引量:2
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作者 Demin Gao Shuo Zhang +2 位作者 Fuquan Zhang Xijian Fan Jinchi Zhang 《Computers, Materials & Continua》 SCIE EI 2019年第5期649-667,共19页
For rechargeable wireless sensor networks,limited energy storage capacity,dynamic energy supply,low and dynamic duty cycles cause that it is unpractical to maintain a fixed routing path for packets delivery permanentl... For rechargeable wireless sensor networks,limited energy storage capacity,dynamic energy supply,low and dynamic duty cycles cause that it is unpractical to maintain a fixed routing path for packets delivery permanently from a source to destination in a distributed scenario.Therefore,before data delivery,a sensor has to update its waking schedule continuously and share them to its neighbors,which lead to high energy expenditure for reestablishing path links frequently and low efficiency of energy utilization for collecting packets.In this work,we propose the maximum data generation rate routing protocol based on data flow controlling technology.For a sensor,it does not share its waking schedule to its neighbors and cache any waking schedules of other sensors.Hence,the energy consumption for time synchronization,location information and waking schedule shared will be reduced significantly.The saving energy can be used for improving data collection rate.Simulation shows our scheme is efficient to improve packets generation rate in rechargeable wireless sensor networks. 展开更多
关键词 Wireless sensor networks maximum data generation rate rechargeable-WSNs
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A new method for improving the inductively coupled data transmission rate of mooring buoy based on carrier signal frequency selection 被引量:1
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作者 Rong Du Xingfei Li +1 位作者 Shaobo Yang Hongyu Li 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2020年第2期96-103,共8页
In the inductively coupled data transmission system of the mooring buoy, the carrier signal frequency of the transmission channel is limited due to the inherent characteristics of the system, resulting in limited chan... In the inductively coupled data transmission system of the mooring buoy, the carrier signal frequency of the transmission channel is limited due to the inherent characteristics of the system, resulting in limited channel bandwidth. The limited channel bandwidth limits the increase in inductively coupled data transmission rate.In order to improve the inductively coupled data transmission rate of mooring buoy as much as possible without damaging the data transmission performance, a new method was proposed in this paper. The method is proposed to improve the data transmission rate by selecting the appropriate carrier signal frequencies based on the principle of maximizing the amplitude value of amplitude-frequency characteristic curve of the system. Research has been done according to this method as follows. Firstly, according to the inductively coupled transmission mooring buoy structure, the inductively coupled data transmission circuit model was established. The binary frequency shift keying(2FSK) digital signal modulation mode was selected. Through theoretical analysis, the relation between the carrier signal frequency and the data transmission performance, the relation between the carrier signal frequency and the 2FSK signal bandwidth were obtained. Secondly, the performance and the bandwidth of the signal transmission were studied for the inherent characteristics of the actual inductively coupled data transmission system. The amplitude-frequency characteristic of the system was analyzed by experiments. By selecting the appropriate carrier signal frequency parameters, an excellent data transmission performance was guaranteed and a large 2FSK signal bandwidth was obtained. Finally, an inductively coupled data transmission rate optimization experiment and a bit error rate analysis experiment were designed and carried out. The results show that the high-speed and reliable data transmission of the system was realized and the rate can reach 100 kbps. 展开更多
关键词 Mooring buoy Inherent characteristics Inductively coupled data transmission rate Carrier signal frequency data transmission performance Amplitude-frequency characteristic
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Enhanced Data Transmission Rate of XCTD Profiler Based on OFDM 被引量:1
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作者 LI Hongzhi ZHANG Sai +2 位作者 QIN Xiaocong ZHANG Xiaoyang ZHENG Yu 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第5期1079-1085,共7页
An expendable conductivity-temperature-depth profiler(XCTD)is one of the most important instruments used to obtain hydrological data,such as temperature and conductivity,and detect ocean depth in a large area.However,... An expendable conductivity-temperature-depth profiler(XCTD)is one of the most important instruments used to obtain hydrological data,such as temperature and conductivity,and detect ocean depth in a large area.However,the XCTD channel provides poor time-varying performance,narrowband,and low signal-to-noise ratio(SNR),which severely restricts the data transmission rate.In contrast to conventional single-carrier modulation techniques,such as amplitude-shift keying and differential phase-shift keying,this article provides a new method,based on orthogonal frequency division multiplexing(OFDM)to enhance the data transmission rate of deep-sea abandoned profilers.We apply the OFDM to enhance the SNR of the XCTD,which is achieved by reducing the data transmission rate of each sub-channel.Moreover,the bandwidth utilization may be improved by increasing the number of subcarriers in a given bandwidth,which enhances the data transmission rate.Based on analysis of the XCTD channel model,OFDM with different parameters such as constellation mapping,number of subcarriers,subcarrier spacing,signal period and cyclic prefix are achieved.To verify the effectiveness of the OFDM,this study investigates the influence of different parameters on the data transmission rate at different noise levels,i.e.,-20 dB and-40 d B. 展开更多
关键词 XCTD OFDM SUBCARRIER BANDWIDTH UTILIZATION data transmission rate
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Fast Rate Fault Detection Filter for Multirate Sampled-data Systems 被引量:3
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作者 ZHONG Mai-Ying MA Chuan-Feng LIU Yun-Xia 《自动化学报》 EI CSCD 北大核心 2006年第3期433-437,共5页
This paper focuses on the fast rate fault detection filter (FDF) problem for a class of multirate sampled-data (MSD) systems. A lifting technique is used to convert such an MSD system into a linear time-invariant disc... This paper focuses on the fast rate fault detection filter (FDF) problem for a class of multirate sampled-data (MSD) systems. A lifting technique is used to convert such an MSD system into a linear time-invariant discrete-time one and an unknown input observer (UIO) is considered as FDF to generate residual. The design of FDF is formulated as an H∞ optimization problem and a solvable condition as well as an optimal solution are derived. The causality of the residual generator can be guaranteed so that the fast rate residual can be implemented via inverse lifting. A numerical example is included to demonstrate the feasibility of the obtained results. 展开更多
关键词 故障检测 滤波器 FDF 残差 MSD系统
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智能超表面辅助多用户系统的通用低复杂度波束成形设计 被引量:1
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作者 陈晓 施建锋 +1 位作者 朱建月 潘存华 《电子与信息学报》 北大核心 2025年第1期128-137,共10页
针对可重构智能超表面(RIS)辅助多用户系统中基站和RIS联合波束成形设计问题,该文提出通用低复杂度联合波束成形设计方案。首先,分析RIS辅助多用户系统以最大化和数据速率为目标的联合波束成形非凸优化问题。其次,利用波束导向矢量近似... 针对可重构智能超表面(RIS)辅助多用户系统中基站和RIS联合波束成形设计问题,该文提出通用低复杂度联合波束成形设计方案。首先,分析RIS辅助多用户系统以最大化和数据速率为目标的联合波束成形非凸优化问题。其次,利用波束导向矢量近似正交性设计RIS反射矩阵,进一步利用迫零方法设计基站发射波束成形,并对多用户进行功率分配优化。最后,讨论该方案适用性并对比该方案的计算复杂度相比现有方案降低了一个数量级。仿真结果表明,所提通用低复杂度波束成形设计可以获得较高和数据速率,并且采用最优功率分配可以进一步提高和数据速率。此外,仿真结果和理论分析都表明系统和数据速率随RIS位置的变化而变化,该结论为RIS位置的选择提供参考依据。 展开更多
关键词 智能超表面 波束成形 和数据速率 低复杂度
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基于擦除编码和副本复制的分布式混合存储研究 被引量:1
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作者 付雄 宋朝阳 +1 位作者 王俊昌 邓松 《计算机科学》 北大核心 2025年第2期42-47,共6页
随着大数据技术、云计算、计算机技术和网络技术的迅猛发展,互联网数据呈爆炸性增长,海量数据的高效存储成为当前互联网技术亟待解决的问题。然而,传统的多副本冗余机制导致了巨大的存储成本,引起了研究者们对新型存储解决方案的关注。... 随着大数据技术、云计算、计算机技术和网络技术的迅猛发展,互联网数据呈爆炸性增长,海量数据的高效存储成为当前互联网技术亟待解决的问题。然而,传统的多副本冗余机制导致了巨大的存储成本,引起了研究者们对新型存储解决方案的关注。在这一背景下,提出了一种基于擦除编码和副本复制的分布式混合存储策略。该策略根据数据特性,对热数据采用副本复制以确保高可靠性和性能,而对冷数据则采用擦除编码以提高存储利用率。基于牛顿冷却定律将数据文件划分为热文件和冷文件,并引入一种自适应的数据温度识别及冷热数据自适应动态分配算法,使系统能够在运行时自动调整冷热数据的比例,然后根据实时数据冷热情况智能调整数据的存储策略,体现了系统在动态环境下的自适应性。其不仅增强了系统对动态工作负载的适应能力,也为提高分布式存储系统在实际应用中的效率和灵活性提供了新的范式。这一创新点在学术和实践层面都具有重要的推动意义。同时,通过仿真实验验证了该策略的有效性和可用性,其为分布式存储系统的优化提供了新的思路。 展开更多
关键词 大数据 副本复制 擦除编码 冷热数据 存储利用率
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基于区块链的车联网数据共享综述 被引量:1
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作者 范艳芳 张哲 +2 位作者 秦天琦 陈若愚 孙英伦 《计算机应用研究》 北大核心 2025年第6期1611-1623,共13页
车联网数据共享,即不同车辆之间或车辆与基础设施之间交换和共享交通数据,可以有效提升驾驶体验、提高驾驶安全性。区块链凭借去中心化、防窜改、可追溯等特性,被广泛应用于车联网环境下的数据共享,为构造一个可信的数据共享环境提供了... 车联网数据共享,即不同车辆之间或车辆与基础设施之间交换和共享交通数据,可以有效提升驾驶体验、提高驾驶安全性。区块链凭借去中心化、防窜改、可追溯等特性,被广泛应用于车联网环境下的数据共享,为构造一个可信的数据共享环境提供了前所未有的机遇。然而将传统区块链应用于车联网数据共享存在不容忽视的挑战,对此已有大量研究工作提出针对性解决方案。结合现有研究对基于区块链的车联网数据共享展开综述,首先介绍了区块链及车联网数据共享的相关背景知识;其次分析基于区块链的车联网数据共享方案的研究现状,总结方案中存在的主要挑战,其中,首次针对其中吞吐率低下及存储开销过大两种主要挑战的现有解决方案进行分析与对比;最后根据车联网及区块链的发展趋势,提出未来可能的研究方向。 展开更多
关键词 车联网 区块链 数据共享 吞吐率 存储开销
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一种用于高性能FPGA的多功能I/O电路
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作者 罗旸 刘波 +3 位作者 曹正州 谢达 张艳飞 单悦尔 《半导体技术》 北大核心 2025年第3期265-272,共8页
为了满足等效系统门数为亿门级现场可编程门阵列(FPGA)的高速率、多功能数据传输需求,设计了一种用于高性能FPGA的多功能输入输出(I/O)电路,工作电压为0.95 V,单个I/O电路的最高数据传输速率为2 Gbit/s。通过在输入逻辑电路中设计同一... 为了满足等效系统门数为亿门级现场可编程门阵列(FPGA)的高速率、多功能数据传输需求,设计了一种用于高性能FPGA的多功能输入输出(I/O)电路,工作电压为0.95 V,单个I/O电路的最高数据传输速率为2 Gbit/s。通过在输入逻辑电路中设计同一边沿流水技术的双倍数据速率(DDR)电路,可以使数据不仅能在相同的时钟沿输出,而且能在同一个时钟周期输出。通过分级采样结合时钟分频和偏移技术,仅需4个时钟周期即可完成8∶1数据的转换。另外,该I/O电路还可以对数据输入输出的延时进行调节,采用粗调和细调相结合的方式,共提供512个延时抽头,并且延时的分辨率达到4 ps。仿真和实测结果表明,该多功能I/O电路能为高性能FPGA提供灵活、多协议的高速数据传输功能。 展开更多
关键词 现场可编程门阵列(FPGA) 输入输出(I/O)电路 多电平标准 双倍数据速率(DDR) 串并转换器(SerDes)
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铁路供电集群监测的VCRS热点缓存替换策略
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作者 屈志坚 李迪 邓芳明 《铁道工程学报》 北大核心 2025年第9期86-91,112,共7页
研究目的:铁路供电集群监测数据中心数据量急剧增加,容易使得监测系统产生延迟,对铁路供电安全造成巨大威胁。针对海量电力数据的处理问题,行业内普遍采用数据库技术缓存热点数据,但现有的缓存替换策略命中率不高,难以有效应对复杂多变... 研究目的:铁路供电集群监测数据中心数据量急剧增加,容易使得监测系统产生延迟,对铁路供电安全造成巨大威胁。针对海量电力数据的处理问题,行业内普遍采用数据库技术缓存热点数据,但现有的缓存替换策略命中率不高,难以有效应对复杂多变的数据访问模式。本文在现有缓存替换策略的基础上设计一种新的VCRS缓存替换策略,通过与传统缓存算法对比,验证方法的高效性。研究结论:(1)提出的VCRS缓存替换策略,在以“时间”为淘汰指标的LRU算法和以“频率”为淘汰指标的LFU算法的基础上进行改进,可充分利用缓存资源,改善整个系统的访问性能;(2)VCRS缓存替换方法在不同的数据访问场景下,可以获得比LRU算法和LFU算法更高的缓存命中率,且耗时与现有缓存替换方法相当;(3)本研究成果可应用于铁路供电集群监测领域,为提高监控系统的快速响应提供新思路。 展开更多
关键词 缓存替换策略 分布式缓存 数据中心 海量数据 缓存命中率
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Call for Papers
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《Digital Communications and Networks》 2025年第4期1304-1304,共1页
SI:Agentic AI for 6G Networks.Introduction.6G networks are poised to provide full coverage across air,land,and sea,deliver terabit-per-second data rates,and achieve microsecond-level latency.They promise comprehensive... SI:Agentic AI for 6G Networks.Introduction.6G networks are poised to provide full coverage across air,land,and sea,deliver terabit-per-second data rates,and achieve microsecond-level latency.They promise comprehensive upgrades across industries through embedded intelligence,ushering in an era of intelligent interconnection of all things.However,managing real-time interactions among devices,infrastructure,and services in 6G networks is much more complex than in previous generations.Massive data streams from terrestrial nodes(e.g.,edge devices,sensors,distributed computing)and non-terrestrial nodes(LEO/MEO/GEO satellites)demand more intelligent and efficient processing. 展开更多
关键词 microsecond level latency embedded intelligenceushering G networks agentic AI intelligent interconnection terabit per second data rates comprehensive upgrades real time interactions
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A Software Reliability Model for OSS Including Various Fault Data Based on Proportional Hazard-Rate Model
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作者 Taku Yanagisawa Yoshinobu Tamura +1 位作者 Adarsh Anand Shigeru Yamada 《American Journal of Operations Research》 2022年第1期1-10,共10页
The </span></span><span><span><span style="font-family:"">software reliability model is the stochastic model to measure the software <span>reliability quantitatively.... The </span></span><span><span><span style="font-family:"">software reliability model is the stochastic model to measure the software <span>reliability quantitatively. A Hazard-Rate Model is </span></span></span></span><span><span><span style="font-family:"">the </span></span></span><span><span><span style="font-family:"">well</span></span></span><span><span><span style="font-family:"">-</span></span></span><span><span><span style="font-family:"">known one as the</span></span></span><span><span><span style="font-family:""> typical software reliability model. We propose Hazard-Rate Models Consider<span>ing Fault Severity Levels (CFSL) for Open Source Software (OSS). The purpose of </span><span>this research is to </span></span></span></span><span><span><span style="font-family:"">make </span></span></span><span><span><span style="font-family:"">the Hazard-Rate Model considering CFSL adapt to</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:"">baseline hazard function and 2 kinds of faults data in Bug Tracking System <span>(BTS)</span></span></span></span><span><span><span style="font-family:"">,</span></span></span><span><span><span style="font-family:""> <i>i.e.</i>, we use the covariate vectors in Cox proportional Hazard-Rate</span></span></span><span><span><span style="font-family:""> Model. Also, <span>we show the numerical examples by evaluating the performance of our pro</span><span>posed model. As the result, we compare the performance of our model with the</span> Hazard-Rate Model CFSL. 展开更多
关键词 Open Source Software Fault data Software Reliability Cox Proportional Hazard-rate Model
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风电机组SCADA“风速-功率”数据处理方法研究 被引量:1
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作者 柳源 李忠虎 +2 位作者 王金明 杨立清 张鑫宇 《太阳能学报》 北大核心 2025年第7期353-360,共8页
在风电机组数据采集与监视控制(SCADA)系统数据中,若噪声数据密度过高,则会在预处理过程中误清洗额定功率数据。使用基于密度的噪声应用空间聚类(DBSCAN)算法剔除额定功率数据附近的噪声数据点,确保仅保留正常的额定功率数据,然后在“风... 在风电机组数据采集与监视控制(SCADA)系统数据中,若噪声数据密度过高,则会在预处理过程中误清洗额定功率数据。使用基于密度的噪声应用空间聚类(DBSCAN)算法剔除额定功率数据附近的噪声数据点,确保仅保留正常的额定功率数据,然后在“风速-功率”曲线上找到额定功率数据与其他数据的分界线,将上半部分暂存,对下半部分采用肖维勒准则与Box_Cox变换相结合的方式处理,最后将两部分数据合并,可有效减少风电机组SCADA数据预处理时,因噪声数据密度过高而误清洗额定功率数据的问题。 展开更多
关键词 风电机组 SCADA系统 数据处理 额定功率数据 DBSCAN聚类算法 肖维勒准则
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基于肿瘤生长率的LI-RADS阈值增长对肝细胞癌(≤3.0 cm)的诊断价值
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作者 邢飞 朱文静 +3 位作者 姜吉锋 陆健 张涛 邢伟 《临床放射学杂志》 北大核心 2025年第1期95-101,共7页
目的探讨基于肿瘤生长率的肝脏影像报告和数据系统(LI-RADS)阈值增长(TG)对肝细胞癌(HCC)(≤3.0 cm)的诊断价值。方法回顾性分析基线、随访均行MRI检查的肝脏局灶性病变(≤3.0 cm),阅片者记录每个病灶随访期间的大小及LR分类调整变化。... 目的探讨基于肿瘤生长率的肝脏影像报告和数据系统(LI-RADS)阈值增长(TG)对肝细胞癌(HCC)(≤3.0 cm)的诊断价值。方法回顾性分析基线、随访均行MRI检查的肝脏局灶性病变(≤3.0 cm),阅片者记录每个病灶随访期间的大小及LR分类调整变化。肿瘤生长率定义为每月病灶增长百分比,包括增长≥10%/月(TG-10%)、≥20%/月(TG-20%)、≥30%/月(TG-30%),并作为改良版TG(mTG)。通过计算诊断优势比(DOR)来确定TG与HCC诊断的相关性。以LR-5为诊断HCC的标准,分别计算基于LI-RADS TG(-,不作为主要征象)、LI-RADS TG(+,作为主要征象)、LI-RADS mTG(+)标准对HCC的诊断效能,包括敏感度、特异度及准确率,两者的比较采用McNemar检验或Fisher’s确切概率法。结果217例患者251个病灶,HCC 159个、非HCC恶性肿瘤23个、良性病变67个。相较于LI-RADS TG(-)标准,基于LI-RADS TG(+)标准可导致14个HCC分类调整,其中,9个由LR-3上调至LR-5[≤19 mm+非环状动脉期高强化(APHE)+TG],5个由LR-4上调至LR-5[(≤19 mm+非环状APHE+强化包膜+TG),n=1;(≥20 mm+非环状APHE+TG),n=5]。TG与HCC显著相关,DOR值为3.65(95%CI:1.63~8.18,P<0.001)。基于LI-RADS TG(+)标准诊断HCC的敏感度(66.7%vs.57.9%,P<0.001)、准确率(82.2%vs.78.4%,P=0.002)高于LI-RADS TG(-),并保持相似特异度(97.8%vs.98.9%,P=0.317)。相较于LI-RADS TG(+)标准,基于LI-RADS mTG-10%标准诊断HCC的准确率显著提高(87.9%vs.82.2%,P<0.001),而mTG-20%(81.2%vs.82.2%,P=0.440)和mTG-30%(78.7%vs.82.2%,P=0.003)的准确率相当或降低。基于LI-RADS mTG-10%标准诊断HCC的敏感度高于LI-RADSTG(+)(78.0%vs.66.7%,P<0.001),而其特异度差异不大(97.8%vs.97.8%,P>0.999)。结论TG作为LI-RADS v2018中的主要征象之一,与HCC显著相关,基于LI-RADS TG(+)标准提高了HCC(尤其表现为非环状APHE+TG)诊断的敏感度、准确率。同时,基于LI-RADS mTG-10%标准进一步提高HCC的诊断效能。 展开更多
关键词 肝细胞癌 肝脏影像报告和数据系统 阈值增长 肿瘤生长率
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轨迹数据驱动的新能源汽车充电站选址模型研究
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作者 曹慕昆 王逸诚 +1 位作者 刘新龙 戴维 《控制与决策》 北大核心 2025年第9期2739-2747,共9页
首先,基于排队论模型,提出充电桩利用率作为充电站选址规划中的重要考虑因素,以用户的充电拒绝率、充电桩利用率以及运营商投资总成本为3个目标建立多目标充电站选址优化模型;然后,通过真实的车辆运动轨迹数据进行实验分析,通过研究车... 首先,基于排队论模型,提出充电桩利用率作为充电站选址规划中的重要考虑因素,以用户的充电拒绝率、充电桩利用率以及运营商投资总成本为3个目标建立多目标充电站选址优化模型;然后,通过真实的车辆运动轨迹数据进行实验分析,通过研究车辆在行驶过程中的驻留行为,分析用户的实际充电需求,在候选点的选取规划中,引入ArcGIS软件,利用其优秀的空间计算能力,在地图中选取合适的候选充电站点;接着,为求解模型,提出一种改进多目标粒子群算法,并与其他智能优化算法进行对比分析,验证所提出改进算法的合理性和有效性;最后,通过仿真实验,进一步分析不同充电站数量以及充电桩功率对于充电站规划过程中各指标的影响.实验结果表明:当充电站数量达到一定规模时,一味地建设充电站并不会使得服务效率得到提升;不同充电功率对于充电站拒绝率影响较小,但是会显著影响到充电桩的利用率. 展开更多
关键词 充电站选址 粒子群算法 ARCGIS 轨迹数据 排队论 充电桩利用率
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基于多重信息融合分析的图书动态自组织分类算法
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作者 窦淑庆 刘思豆 《现代电子技术》 北大核心 2025年第11期169-173,共5页
为提高图书资源管理的智能化水平以及个性化服务的精准度,文中提出一种基于深度学习和多重信息融合分析的图书馆动态自组织分类算法。在构建数据感知与处理基本架构的基础上,引入深度学习算法对各类数据中的海量信息进行快速分析与感知... 为提高图书资源管理的智能化水平以及个性化服务的精准度,文中提出一种基于深度学习和多重信息融合分析的图书馆动态自组织分类算法。在构建数据感知与处理基本架构的基础上,引入深度学习算法对各类数据中的海量信息进行快速分析与感知,同时对感知后的数据进行动态分类,从而实现大规模数据的智能化处理。基于深度学习算法,引入多重信息融合技术,对各类数据的多种信息进行有效识别与融合,实现对读者行为和偏好的精准捕捉,为图书资源的优化管理提供了技术解决方案。为了验证所提方法的正确性和有效性,设计了数值实验进行测试。实验结果表明,所提方法的数据分类准确率可达99.10%,能够满足大型图书馆的智能化数据管理与分类需求。 展开更多
关键词 图书资源管理 智能化水平 个性化服务 深度学习 多重信息融合分析 动态自组织分类算法 数据分类准确率
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相邻价格相关的在线单向交易问题的数据驱动型策略设计
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作者 张文明 杜玉禄 《中国管理科学》 北大核心 2025年第5期26-33,共8页
本文首先将竞争比准则和竞争差准则相结合提出了λ-竞争率准则,并基于λ-竞争率准则提出了能够发挥历史数据作用的数据驱动型在线策略的设计框架,然后将该框架应用到了相邻价格相关的在线单向交易问题的在线策略设计中。把所设计的基于... 本文首先将竞争比准则和竞争差准则相结合提出了λ-竞争率准则,并基于λ-竞争率准则提出了能够发挥历史数据作用的数据驱动型在线策略的设计框架,然后将该框架应用到了相邻价格相关的在线单向交易问题的在线策略设计中。把所设计的基于λ-竞争率准则的数据驱动型在线策略应用到湖北、上海、广州和深圳碳排放权交易所的交易数据中发现,该策略能够获得比基于竞争比准则和竞争差准则的最优在线策略更高的平均收益,表明基于λ-竞争率准则的数据驱动型在线策略在价格序列波动频繁和难以预测的情况下更具稳健性。 展开更多
关键词 单向交易 数据驱动型策略 λ-竞争率 竞争比 竞争差
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