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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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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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医院感染监测数据真实性评估:基于随机抽样的发病与漏报研究
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作者 周芸 向天新 +4 位作者 罗亭 康秀华 刘珉玉 庞水子 肖声平 《中国感染控制杂志》 北大核心 2026年第3期402-406,共5页
目的分析医院感染病例漏报现状,识别高漏报科室与感染类型。方法基于分阶段随机抽样设计,回顾性调查江西省某三级甲等综合医院分院区所有临床科室2024年2月1日—12月31日的出院患者。由医院感染管理专职人员判定医院感染与漏报病例,比... 目的分析医院感染病例漏报现状,识别高漏报科室与感染类型。方法基于分阶段随机抽样设计,回顾性调查江西省某三级甲等综合医院分院区所有临床科室2024年2月1日—12月31日的出院患者。由医院感染管理专职人员判定医院感染与漏报病例,比较分析医院感染与漏报病例特征。结果共调查12106例患者,覆盖全院33个临床科室。确诊医院感染病例157例,发病率为1.30%;其中漏报病例77例,漏报率为49.04%。不同科室医院感染发病率比较,差异有统计学意义(P<0.001),ICU发病率最高(20.56%)。不同科室医院感染漏报率比较,差异有统计学意义(P<0.001),外科漏报率最高(82.05%)。157例医院感染病例中,主要感染部位为下呼吸道(76例,48.41%)、血液(24例,15.29%)、泌尿道(14例,8.92%)等。不同感染部位漏报率比较,差异无统计学意义(P=0.173)。手术部位感染漏报率为83.33%,皮肤软组织感染漏报率为66.67%。结论医院感染漏报问题突出,亟需强化医生对医院感染的定义、诊断及上报的认知,优化监测流程,协调疾病诊断相关分组绩效管理与上报激励,提升医院感染监测数据真实性。 展开更多
关键词 医院感染 漏报率 随机抽样 数据质量 真实性 监测
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中国智能制造业数据资产折旧率和存量测算
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作者 曹景林 郭熠倩 +1 位作者 解鑫垚 谢瑾 《统计学报》 2026年第1期12-23,共12页
为厘清数据资产在智能制造业中价值累积和折旧损耗的内在规律,依据利润最大化原则推导资产折旧率方程,分别采用三种生产函数构建测算模型并进行模拟分析,以此估测我国智能制造业的数据资产折旧率。同时,借鉴Griliches思想改进永续盘存法... 为厘清数据资产在智能制造业中价值累积和折旧损耗的内在规律,依据利润最大化原则推导资产折旧率方程,分别采用三种生产函数构建测算模型并进行模拟分析,以此估测我国智能制造业的数据资产折旧率。同时,借鉴Griliches思想改进永续盘存法,测算智能制造业的数据资产存量。结果表明:改进的CES生产函数测算结果具备理论适配性;基于该模型得到的数据资产折旧率为10.70%,这一数值既反映了技术迭代引发的数据时效性衰减效应,也体现了数据资产特有的网络外部性和增值效应;我国智能制造业的数据资产存量呈指数型增长趋势,自1995年起先后经历了萌芽期、驱动期、引领期与协同期,2018年以来存量增长率逐渐趋于稳定。 展开更多
关键词 智能制造 数据资产 折旧率 存量 CES生产函数 超越对数生产函数 知识资本 价格指数
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地震动大数据降维及其特征母波频谱分析
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作者 王晨 俞瑞芳 +1 位作者 杨千里 杨柳青 《振动工程学报》 北大核心 2026年第2期413-423,共11页
通过数值拟合得到满足工程需求的设计地震动时程是弥补现有强震记录较少或在区域上分布不均匀的重要方法。由于强震记录中包含着来自震源、传播路径及场地等信息,因此直接采用实际记录进行地震动拟合可以反映工程场地的地震地质环境。... 通过数值拟合得到满足工程需求的设计地震动时程是弥补现有强震记录较少或在区域上分布不均匀的重要方法。由于强震记录中包含着来自震源、传播路径及场地等信息,因此直接采用实际记录进行地震动拟合可以反映工程场地的地震地质环境。现面临的问题是如何从大量的原始地震动记录中提取出数量合理且包含主要特征的地震动。本文考虑影响地震动特性的主要因素,基于震级、距离和场地条件,对强震记录进行分组形成地震动数据集;引入主成分分析(principal component analysis,PCA)算法,分析一个数据集的特征值、特征母波与原始地震动频谱特征之间的相关性;通过探讨影响特征母波频谱特性的因素,提出了实现地震动数据降维的累计方差解释率(cumulative variance explanatory rate,CVE)阈值,并以土耳其地震(Mw7.6)记录为目标进行了地震动拟合,进一步明确了地震动样本数量和CVE阈值的相关性,及其对地震动拟合结果的影响,为实现大量地震动数据的降维提供了可靠的理论依据。 展开更多
关键词 主成分分析 数据降维 累积方差解释率 地震动拟合 土耳其地震
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基于辅助评论的交互注意力推荐方法
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作者 孙清昊 李梓杨 +1 位作者 于炯 陈鹏程 《计算机工程与设计》 北大核心 2026年第1期73-81,共9页
针对基于评论文本的推荐中评论数据稀疏且用户个性化挖掘不足导致的推荐性能不佳的问题,提出一种个性化的神经推荐模型(PNRR)。实现辅助评论算法选择合适的评论作为补充信息,以此缓解数据稀疏导致的用户和项目建模的特征缺失问题;设计... 针对基于评论文本的推荐中评论数据稀疏且用户个性化挖掘不足导致的推荐性能不佳的问题,提出一种个性化的神经推荐模型(PNRR)。实现辅助评论算法选择合适的评论作为补充信息,以此缓解数据稀疏导致的用户和项目建模的特征缺失问题;设计双重个性化交互注意力机制深入挖掘用户个性化,促进用户和项目特征建模过程中的信息交互并对辅助评论中存在的不相关特征进行过滤。在Amazon的多个公开数据集上的实验结果表明,该模型在评分预测任务上优于现有模型,且具有较强的可解释性。 展开更多
关键词 推荐系统 评论文本 辅助评论 注意力机制 个性化建模 数据稀疏 评分预测
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基于BPPM调制的非直视紫外光通信在异步周期脉冲干扰下的性能分析
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作者 曹天 王平 王凯乐 《南京邮电大学学报(自然科学版)》 北大核心 2026年第1期47-55,共9页
随着紫外光通信技术在无人机平台上的应用,对地面非直视紫外光通信系统带来潜在威胁。针对基于二元脉冲位置调制(Binary Pulse-Position Modulation,BPPM)的非直视紫外光通信系统,首先推导了在异步周期脉冲干扰下BPPM符号的两个时隙中... 随着紫外光通信技术在无人机平台上的应用,对地面非直视紫外光通信系统带来潜在威胁。针对基于二元脉冲位置调制(Binary Pulse-Position Modulation,BPPM)的非直视紫外光通信系统,首先推导了在异步周期脉冲干扰下BPPM符号的两个时隙中干扰信号的联合概率质量函数。进一步推导了系统平均误码率和可达速率的理论闭合表达式,并使用蒙特卡洛仿真对理论结果进行了验证。最后,给出了在不同干扰距离、发射端峰值光功率以及干扰脉冲参数下的性能结果。结果表明,相较于开关键控,非直视紫外光通信系统采用BPPM可以获得更加优异的抗干扰性能。 展开更多
关键词 紫外光通信 周期脉冲干扰 抗干扰技术 二元脉冲位置调制 平均误码率 可达速率
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面向电商数据库的用户行为数据挖掘算法研究
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作者 刘敏 刘静 《信息与电脑》 2026年第4期49-51,共3页
文章以电商数据库中浏览、加购、下单等用户行为数据为研究对象,采用数据预处理、特征工程结合改进协同过滤算法构建挖掘模型。通过对某电商平台真实数据集的测试,模型在用户偏好预测准确率与商品推荐转化率上较传统算法分别提升12.3%与... 文章以电商数据库中浏览、加购、下单等用户行为数据为研究对象,采用数据预处理、特征工程结合改进协同过滤算法构建挖掘模型。通过对某电商平台真实数据集的测试,模型在用户偏好预测准确率与商品推荐转化率上较传统算法分别提升12.3%与9.7%。研究表明,该挖掘算法可有效提取用户行为数据中的潜在规律,为电商平台优化运营策略提供可靠技术支持。 展开更多
关键词 电商数据库 用户行为数据 数据挖掘 协同过滤算法 推荐转化率
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多数据传输速率SerDes的测试方法研究
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作者 曹睿 张霞 +2 位作者 李智超 王兆辉 侯帅康 《电子与封装》 2026年第1期48-56,共9页
串行器/解串器(SerDes)参数测试是芯片测试中不可缺少的一部分,但是涉及到多数据传输速率SerDes发送端和接收端测试通常需要分别进行,并且测试环境较为复杂,频繁更改测试环境会导致测试流程冗长且可靠性较低。基于一款多数据传输速率交... 串行器/解串器(SerDes)参数测试是芯片测试中不可缺少的一部分,但是涉及到多数据传输速率SerDes发送端和接收端测试通常需要分别进行,并且测试环境较为复杂,频繁更改测试环境会导致测试流程冗长且可靠性较低。基于一款多数据传输速率交换芯片的测试需求,构建出一套可以同时进行多数据传输速率SerDes发送端和接收端测试的环境,并且可以在此基础上进行高低温测试,测试流程中环境不需要进行任何更改。测试结果表明,该测试系统可以满足被测芯片SerDes在4.250~53.125 Gbit/s传输速率下发送端、接收端的三温测试,测试方法便利且测试数据真实可靠。 展开更多
关键词 SerDes测试 多数据传输速率测试 高低温测试 误码率 眼图
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基于深度学习的多模态遥感数据石冰川分类模型研究
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作者 吝路军 张艳妮 +3 位作者 刘磊 冯敏 文雯 尹芳 《地学前缘》 北大核心 2026年第4期187-202,共16页
石冰川可分为活动型、转换型与遗迹型,其在含水量、古气候信息保存能力及灾害风险等级等方面具有显著差异,系统开展石冰川分类对理解气候演变、评估高寒区水资源具有重要意义。目前,基于光学遥感的地貌特征可实现石冰川的类型区分,但缺... 石冰川可分为活动型、转换型与遗迹型,其在含水量、古气候信息保存能力及灾害风险等级等方面具有显著差异,系统开展石冰川分类对理解气候演变、评估高寒区水资源具有重要意义。目前,基于光学遥感的地貌特征可实现石冰川的类型区分,但缺乏量化依据;基于雷达遥感的运动特征虽能实现定量分类,却存在大量未定义类型。融合两类遥感数据,可同时弥补光学数据定量能力不足与雷达数据分类不全的局限。本研究联合Sentinel-2影像与LOS形变速率数据构建代表性样本集,结合深度学习与集成学习策略,建立了高精度石冰川三分类模型及强普适性的分类流程。模型在训练集、测试集与验证集上的F1-score均高于0.90,表现出良好的泛化性能。在青藏高原五个典型区域的分类验证中,模型显示出较强的实用性。特征重要性分析表明,该深度学习框架能有效融合雷达与光学信息,发挥二者在石冰川分类中的互补优势。本方法为青藏高原及其他高山地区石冰川的高精度分类提供了新的技术途径。 展开更多
关键词 石冰川分类 Sentinel-2影像 LOS形变速率数据 深度学习 多模态遥感融合
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基于光响应模型与机器学习的番茄光合速率预测
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作者 王柯如 任妮 +3 位作者 毛晓娟 刘杨 李远 金晶 《中国农机化学报》 北大核心 2026年第1期223-230,共8页
构建温室作物光合速率预测模型对理解作物光合作用受环境因素的影响机制,优化作物生长条件,提高设施农业的智能化水平具有重要意义。为实现温室番茄光合速率的精准预测,开展不同温度、光量子通量密度嵌套试验,基于温度修正的直角双曲线... 构建温室作物光合速率预测模型对理解作物光合作用受环境因素的影响机制,优化作物生长条件,提高设施农业的智能化水平具有重要意义。为实现温室番茄光合速率的精准预测,开展不同温度、光量子通量密度嵌套试验,基于温度修正的直角双曲线模型、非直角双曲线模型、指数模型、直角双曲线修正模型、鲸鱼优化支持向量机回归算法和深度森林模型分别建立光合速率预测模型,并对比分析6个模型的预测效果。结果表明,机器学习算法预测精度优于光响应模型,其中鲸鱼优化支持向量机回归算法效果最佳,RMSE、MAE和R^(2)分别为1.9717、1.3943、0.8658μmol/(m^(2)·s);光响应模型中,温度修正直角双曲线模型预测精度最佳,RMSE、MAE和R^(2)分别为2.5934、1.8750、0.7635μmol/(m^(2)·s)。研究表明,机器学习可以实现番茄光合速率精准预测,从而解析光合速率最优下对应的光温最佳参数值,可为设施光温优化调控提供支撑。 展开更多
关键词 番茄 光合速率 机理模型 数据模型 机器学习
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台站级天气雷达数据质量控制方法探索
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作者 邹红 姚朋 罗予 《气象水文海洋仪器》 2026年第1期19-22,25,共5页
文章着力于解决台站级雷达业务工作中出现的疑误数据问题,对南充国家天气雷达站2020-2023年出现的电磁干扰、地物干扰、系统故障等引起的异常回波、空回波对应的疑误数据进行统计和分析,总结了一套基于对地物回波的变化进行监控来探索... 文章着力于解决台站级雷达业务工作中出现的疑误数据问题,对南充国家天气雷达站2020-2023年出现的电磁干扰、地物干扰、系统故障等引起的异常回波、空回波对应的疑误数据进行统计和分析,总结了一套基于对地物回波的变化进行监控来探索台站级天气雷达数据质量控制方法。开发雷达标准格式数据可视化平台,经质控算法能快速识别地物杂波、系统异常回波、同频干扰回波并及时短信告警。便于雷达业务人员及时发现问题,从源头上控制和减少疑误数据,进而提高新一代天气雷达设备稳定运行率和雷达数据质量。 展开更多
关键词 数据疑误 数据可疑 数据质量 同频干扰 设备稳定运行率
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数据驱动思路助力化学反应速率常数测定实验的研究
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作者 黄坚 张明珏 +4 位作者 马尚初 董佳 吴官梓 温爱明 刘卓靓 《大学化学》 2026年第1期213-226,共14页
测定镁条与稀硫酸反应的速率常数是多所高校的基础无机化学实验。然而用一级动力学模型拟合时,容易观察到反应后半段的数据不符合模型。为了验证副反应的猜想,我们引入了pH值数据,设计了规范化自动化的实验过程和数据采集;我们开发了数... 测定镁条与稀硫酸反应的速率常数是多所高校的基础无机化学实验。然而用一级动力学模型拟合时,容易观察到反应后半段的数据不符合模型。为了验证副反应的猜想,我们引入了pH值数据,设计了规范化自动化的实验过程和数据采集;我们开发了数据处理的小程序包,用于深入研究镁条与硫酸之间的反应速率常数。实验发现主反应(Mg与H_(2)SO_(4))为一级反应,其速率常数随温度升高显著增加;副反应(Mg与H_(2)O)符合二级动力学特征,活化能达127.79 kJ‧mol^(‒1)。本论文通过多维度数据协同分析、自动化数据处理流程设计,对主副反应动力学特征进行了交叉验证,解释了电导率数据偏离现象。本论文将传统验证性实验转化为研究型教学载体,实现了“数据驱动研究”范式与实验教学的融合,为理工科非化学专业学生培养创新思维与数字化问题解决能力提供了实践范例。 展开更多
关键词 化学反应速率常数 数字化设计 数据驱动研究 数据处理程序包
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