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基于BIM表达的Laplace变换求解桩土地基动力相互作用
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作者 熊辉 赵铭 《铁道科学与工程学报》 北大核心 2026年第4期1675-1688,共14页
为高效研究分析群桩-土动力相互作用,结合数值计算和三维可视化,本文基于Laplace变换与建筑信息模型(BIM)技术的深度融合,构建了桩土地基动力相互作用数值计算-三维可视化协同分析框架。基于连续介质动力学理论,建立桩-土黏弹性耦合效... 为高效研究分析群桩-土动力相互作用,结合数值计算和三维可视化,本文基于Laplace变换与建筑信息模型(BIM)技术的深度融合,构建了桩土地基动力相互作用数值计算-三维可视化协同分析框架。基于连续介质动力学理论,建立桩-土黏弹性耦合效应的运动微分方程体系;通过引入Laplace变换,将时域微分方程转换为频域代数方程,有效规避了时域积分步长限制导致的累积误差问题,推导了考虑土体分层特性与桩端约束条件的位移解析解,采用Revit平台开发参数化建模插件,建立包含土层弹阻、群桩体空间、几何参数及材料属性等的频域三维信息模型。通过C#编程语言二次开发,实现了与Revit模型的数据交互,将求得的桩身位移场转化为NURBS曲线控制点坐标,利用SweptBlend方法生成了具有物理真实性的桩体振型曲面,并通过对具体工程实例的应用研究,验证了该方法的可行性。研究结果表明:该方法不仅能够描述群桩在不同工况下的振动特性,还利用BIM的可视化表达结合Laplace变换,使复杂的振型信息更易于理解,并显著提升了群桩-土相互作用分析的效率和精度。研究结果可为桩土地基动力相互作用分析提供具有前瞻性的数字化、可视化与智能化可行方案,并有助于更准确地进行安全评估和降低工程风险。 展开更多
关键词 桩承结构 群桩-土动力反应 群桩阻抗 LAPLACE变换 BIM(building information model)
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The gap between principle and practice of lossy image coding
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作者 Haotian Zhang Dong Liu 《Journal of University of Science and Technology of China》 北大核心 2026年第1期1-12,I0001,共13页
Lossy image coding is the art of computing that is principally bounded by the image’s rate-distortion function.This bound,though never accurately characterized,has been approached practically via deep learning techno... Lossy image coding is the art of computing that is principally bounded by the image’s rate-distortion function.This bound,though never accurately characterized,has been approached practically via deep learning technologies in recent years.Indeed,learned image coding schemes allow direct optimization of the joint rate-distortion cost,thereby outperforming the handcrafted image coding schemes by a large margin.Still,it is observed that there is room for further improvement in the rate-distortion performance of learned image coding.In this article,we identify the gap between the ideal rate-distortion function forecasted by Shannon’s information theory and the empirical rate-distortion function achieved by the state-of-the-art learned image coding schemes,revealing that the gap is incurred by five different effects:modeling effect,approximation effect,amortization effect,digitization effect,and asymptotic effect.We design simulations and experiments to quantitatively evaluate the last three effects,which demonstrates the high potential of future lossy image coding technologies. 展开更多
关键词 information theory learned image coding lossy image coding rate-distortion function
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Millimeter wave imaging of Range Migration Algorithm with adaptive background filtering
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作者 CHENG Zhi-Hua ZHOU Ran +3 位作者 WANG Meng YU Tao WANG Yu-Lan YAO Jian-Quan 《红外与毫米波学报》 北大核心 2026年第2期279-284,共6页
This paper proposes a novel Range Migration Algorithm(RMA)integrated with an adaptive background filtering method specifically designed for near-field millimeter-wave imaging scenarios where targets are in close proxi... This paper proposes a novel Range Migration Algorithm(RMA)integrated with an adaptive background filtering method specifically designed for near-field millimeter-wave imaging scenarios where targets are in close proximity to background structures.This method simulates the attention distribution mode of the human visual system which is used in Artificial Intelligence(AI)and called the Attention Mechanism.Based on the concept of static clutter filtering,the frequency-domain signals of the scanning aperture are divided into grid cells.Background scattering functions are established by analyzing the motion processes within each cell,and the background interference is linearly filtered out.An analysis of the manifestation of background scattering interference within the algorithm is carried out,and the impact of the grid cell dimension on the imaging quality is investigated.Experimental results show that the proposed method exhibits the capability to enhance the signal-to-noise ratio of both the target and the background.It effectively suppresses the background interference,leading to a more prominent image,meanwhile without imposing the excessive computational load.The method offers a novel solution for improving the performance of millimeter-wave imaging technology in practical applications. 展开更多
关键词 information processing technology millimeter-wave imaging Range Migration Algorithm(RMA) attention mechanism adaptive background filtering
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上海交通大学医学院医学技术学院李文杰发表医学人工智能领域研究成果
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《上海交通大学学报(医学版)》 北大核心 2026年第2期187-187,共1页
2025年12月22日,上海交通大学医学院医学技术学院李文杰在人工智能与信息融合领域国际顶级期刊Information Fusion发表了一项研究成果“CX-Mind:a pioneering multimodal large language model for interleaved reasoning in chest X-ra... 2025年12月22日,上海交通大学医学院医学技术学院李文杰在人工智能与信息融合领域国际顶级期刊Information Fusion发表了一项研究成果“CX-Mind:a pioneering multimodal large language model for interleaved reasoning in chest X-ray via curriculum-guided reinforcement learning”。 展开更多
关键词 医学人工智能 Information Fusion
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BIM技术赋能在役桥梁安全与高效运维 被引量:2
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作者 张丽萍 王广 +2 位作者 王力 陈云峰 李子奇 《中国安全生产科学技术》 北大核心 2025年第1期101-108,共8页
为了保证运维阶段桥梁结构安全,提升桥梁运维工作的效率,开展公路混凝土梁式桥运维阶段建筑信息模型(building information modeling,BIM)技术应用研究。在对公路桥梁现行编码体系进行扩展的基础上,提出1种参数化快速建模方法,以快速完... 为了保证运维阶段桥梁结构安全,提升桥梁运维工作的效率,开展公路混凝土梁式桥运维阶段建筑信息模型(building information modeling,BIM)技术应用研究。在对公路桥梁现行编码体系进行扩展的基础上,提出1种参数化快速建模方法,以快速完成桥梁构件族的创建与整体模型的集成。借助Autodesk Revit软件应用程序编程接口(application programming interface,API),采用C#语言,开发公路混凝土梁式桥智慧运维状态评估系统,以实际工程应用进行验证分析。研究结果表明:全面统一的桥梁信息编码体系,能够提高桥梁信息统计与检索效率;提出的快速建模方法能够显著减少建模工作量,建模时间较传统建模方法可减少60%,并保证模型的准确性与规范性;运维状态评估系统能够实现养护数据的充分利用与桥梁评定工作的自动化,通过对桥梁运维信息的有效组织,实现服役性能的长期追踪,从而确保运营期桥梁结构状态安全稳定。研究结果可为公路混凝土梁式桥运维管理提供技术支撑,提升桥梁运维的数字化水平。 展开更多
关键词 桥梁工程 运维状态评估系统 Building Information Modeling 公路混凝土梁式桥
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A review of current studies on the unmanned aerial vehicle-based moving target tracking methods 被引量:3
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作者 Binbin Yan Yuxin Wei +3 位作者 Shuangxi Liu Wei Huang Ruizhe Feng Xiaoqian Chen 《Defence Technology(防务技术)》 2025年第9期201-219,共19页
Unmanned aerial vehicles(UAVs)have become crucial tools in moving target tracking due to their agility and ability to operate in complex,dynamic environments.UAVs must meet several requirements to achieve stable track... Unmanned aerial vehicles(UAVs)have become crucial tools in moving target tracking due to their agility and ability to operate in complex,dynamic environments.UAVs must meet several requirements to achieve stable tracking,including maintaining continuous target visibility amidst occlusions,ensuring flight safety,and achieving smooth trajectory planning.This paper reviews the latest advancements in UAV-based target tracking,highlighting information prediction,tracking strategies,and swarm cooperation.To address challenges including target visibility and occlusion,real-time prediction and tracking in dynamic environments,flight safety and coordination,resource management and energy efficiency,the paper identifies future research directions aimed at improving the performance,reliability,and scalability of UAV tracking system. 展开更多
关键词 Unmanned aerial vehicle(UAV) Tracking methods Moving targets Information prediction Tracking strategies Swarm cooperation
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Three-dimensional finite-time optimal cooperative guidance with integrated information fusion observer 被引量:1
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作者 Yiao Zhan Linwei Wang Di Zhou 《Defence Technology(防务技术)》 2025年第4期12-28,共17页
Intercepting high-maneuverability hypersonic targets in near-space environments poses significant challenges due to their extreme speeds and evasive capabilities.To address these challenges,this study presents an inte... Intercepting high-maneuverability hypersonic targets in near-space environments poses significant challenges due to their extreme speeds and evasive capabilities.To address these challenges,this study presents an integrated approach that combines a Three-Dimensional Finite-Time Optimal Cooperative Guidance Law(FTOC)with an Information Fusion Anti-saturation Predefined-time Observer(IFAPO).The proposed FTOC guidance law employs a nonlinear,non-quadratic finite-time optimal control strategy designed for rapid convergence within the limited timeframes of near-space interceptions,avoiding the need for remaining flight time estimation or linear decoupling inherent in traditional methods.To complement the guidance strategy,the IFAPO leverages multi-source information fusion theory and incorporates anti-saturation mechanisms to enhance target maneuver estimation.This method ensures accurate and real-time prediction of target acceleration while maintaining predefined convergence performance,even under complex interception conditions.By integrating the FTOC guidance law and IFAPO,the approach optimizes cooperative missile positioning,improves interception success rates,and minimizes fuel consumption,addressing practical constraints in military applications.Simulation results and comparative analyses confirm the effectiveness of the integrated approach,demonstrating its capability to achieve cooperative interception of highly maneuvering targets with enhanced efficiency and reduced economic costs,aligning with realistic combat scenarios. 展开更多
关键词 Anti-saturation predefined-time observer Nonlinear finite-time optimal control Three-dimensional guidance Information fusion
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Target intention prediction of air combat based on Mog-GRU-D network under incomplete information 被引量:1
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作者 CHEN Jun SUN Xiang +1 位作者 XUE Zhe ZHANG Xinyu 《Journal of Systems Engineering and Electronics》 2025年第4期972-984,共13页
High complexity and uncertainty of air combat pose significant challenges to target intention prediction.Current interpolation methods for data pre-processing and wrangling have limitations in capturing interrelations... High complexity and uncertainty of air combat pose significant challenges to target intention prediction.Current interpolation methods for data pre-processing and wrangling have limitations in capturing interrelationships among intricate variable patterns.Accordingly,this study proposes a Mogrifier gate recurrent unit-D(Mog-GRU-D)model to address the com-bat target intention prediction issue under the incomplete infor-mation condition.The proposed model directly processes miss-ing data while reducing the independence between inputs and output states.A total of 1200 samples from twelve continuous moments are captured through the combat simulation system,each of which consists of seven dimensional features.To bench-mark the experiment,a missing valued dataset has been gener-ated by randomly removing 20%of the original data.Extensive experiments demonstrate that the proposed model obtains the state-of-the-art performance with an accuracy of 73.25%when dealing with incomplete information.This study provides possi-ble interpretations for the principle of target interactive mecha-nism,highlighting the model’s effectiveness in potential air war-fare implementation. 展开更多
关键词 intention prediction incomplete information gate recurrent unit(GRU) Mogrifier interaction mechanism.
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Exploration of augmented prompting methods for information extraction using large language models
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作者 Yishuo Fu Benfeng Xu +2 位作者 Mingxuan Du Quan Wang Zhendong Mao 《中国科学技术大学学报》 北大核心 2025年第7期15-24,14,I0001,共12页
Information extraction(IE)aims to automatically identify and extract information about specific interests from raw texts.Despite the abundance of solutions based on fine-tuning pretrained language models,IE in the con... Information extraction(IE)aims to automatically identify and extract information about specific interests from raw texts.Despite the abundance of solutions based on fine-tuning pretrained language models,IE in the context of fewshot and zero-shot scenarios remains highly challenging due to the scarcity of training data.Large language models(LLMs),on the other hand,can generalize well to unseen tasks with few-shot demonstrations or even zero-shot instructions and have demonstrated impressive ability for a wide range of natural language understanding or generation tasks.Nevertheless,it is unclear,whether such effectiveness can be replicated in the task of IE,where the target tasks involve specialized schema and quite abstractive entity or relation concepts.In this paper,we first examine the validity of LLMs in executing IE tasks with an established prompting strategy and further propose multiple types of augmented prompting methods,including the structured fundamental prompt(SFP),the structured interactive reasoning prompt(SIRP),and the voting-enabled structured interactive reasoning prompt(VESIRP).The experimental results demonstrate that while directly promotes inferior performance,the proposed augmented prompt methods significantly improve the extraction accuracy,achieving comparable or even better performance(e.g.,zero-shot FewNERD,FewNERD-INTRA)than state-of-theart methods that require large-scale training samples.This study represents a systematic exploration of employing instruction-following LLM for the task of IE.It not only establishes a performance benchmark for this novel paradigm but,more importantly,validates a practical technical pathway through the proposed prompt enhancement method,offering a viable solution for efficient IE in low-resource settings. 展开更多
关键词 prompt learning natural language processing few-shot information extraction zero-shot information extraction
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An empirical study of user’s online electric vehicle car-hailing behavior based on the HSM model in the context of coordinated carbon and electricity markets
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作者 Yuan Zhang Jun Li +1 位作者 Linlin Fan Ao Zhang 《Journal of University of Science and Technology of China》 北大核心 2025年第11期12-24,I0001,共14页
The transportation sector’s reliance on petroleum fuels exacerbates environmental issues,emphasizing the need for sustainable development.Online electric vehicle(EV)car-hailing services present a key opportunity for ... The transportation sector’s reliance on petroleum fuels exacerbates environmental issues,emphasizing the need for sustainable development.Online electric vehicle(EV)car-hailing services present a key opportunity for EV adoption.This study develops a model based on heuristic and systematic information processing,examining the impacts of factors such as perceived risk,information need,and experience and knowledge on users’utilization of online electric vehicle carhailing services.The results indicate that users’experience and knowledge increase their information need and promote both heuristic and systematic processing,leading to positive attitude change,although they don’t significantly affect perceived risk.Perceived risk increases information need and supports supports systematic processing but negatively impacts attitude change.Greater information enhances systematic processing and attitude change.Perceived risk and information need do not affect attitude change via heuristic processing.Finally,the paper concludes with implications and directions for future research. 展开更多
关键词 online electric vehicle car-hailing service car-hailing crisis perceived risk attitude change heuristic and systematic information processing
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Factor graph method for target state estimation in bearing-only sensor network
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作者 CHEN Zhan FANG Yangwang +1 位作者 ZHANG Ruitao FU Wenxing 《Journal of Systems Engineering and Electronics》 2025年第2期380-396,共17页
For target tracking and localization in bearing-only sensor network,it is an essential and significant challenge to solve the problem of plug-and-play expansion while stably enhancing the accuracy of state estimation.... For target tracking and localization in bearing-only sensor network,it is an essential and significant challenge to solve the problem of plug-and-play expansion while stably enhancing the accuracy of state estimation.This paper pro-poses a distributed state estimation method based on two-layer factor graph.Firstly,the measurement model of the bearing-only sensor network is constructed,and by investigating the observ-ability and the Cramer-Rao lower bound of the system model,the preconditions are analyzed.Subsequently,the location fac-tor graph and cubature information filtering algorithm of sensor node pairs are proposed for localized estimation.Building upon this foundation,the mechanism for propagating confidence mes-sages within the fusion factor graph is designed,and is extended to the entire sensor network to achieve global state estimation.Finally,groups of simulation experiments are con-ducted to compare and analyze the results,which verifies the rationality,effectiveness,and superiority of the proposed method. 展开更多
关键词 factor graph cubature information filtering bearing-only sensor network state estimation
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Feature selection for determining input parameters in antenna modeling
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作者 LIU Zhixian SHAO Wei +2 位作者 CHENG Xi OU Haiyan DING Xiao 《Journal of Systems Engineering and Electronics》 2025年第1期15-23,共9页
In this paper,a feature selection method for determining input parameters in antenna modeling is proposed.In antenna modeling,the input feature of artificial neural network(ANN)is geometric parameters.The selection cr... In this paper,a feature selection method for determining input parameters in antenna modeling is proposed.In antenna modeling,the input feature of artificial neural network(ANN)is geometric parameters.The selection criteria contain correlation and sensitivity between the geometric parameter and the electromagnetic(EM)response.Maximal information coefficient(MIC),an exploratory data mining tool,is introduced to evaluate both linear and nonlinear correlations.The EM response range is utilized to evaluate the sensitivity.The wide response range corresponding to varying values of a parameter implies the parameter is highly sensitive and the narrow response range suggests the parameter is insensitive.Only the parameter which is highly correlative and sensitive is selected as the input of ANN,and the sampling space of the model is highly reduced.The modeling of a wideband and circularly polarized antenna is studied as an example to verify the effectiveness of the proposed method.The number of input parameters decreases from8 to 4.The testing errors of|S_(11)|and axis ratio are reduced by8.74%and 8.95%,respectively,compared with the ANN with no feature selection. 展开更多
关键词 antenna modeling artificial neural network(ANN) feature selection maximal information coefficient(MIC)
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起伏地形下重庆降水精细的空间分布 被引量:25
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作者 陆忠艳 马力 +2 位作者 缪启龙 代强 王扬锋 《南京气象学院学报》 CSCD 北大核心 2006年第3期408-412,共5页
采用重庆地区34个气象观测站1971—2000年30 a平均月降水总量资料,以及重庆地区100 m×100 m DEM(D igital E levation Model)数据,对重庆地区降水空间分布进行研究。根据山地气候学原理,利用GIS(Geographical Information Systems... 采用重庆地区34个气象观测站1971—2000年30 a平均月降水总量资料,以及重庆地区100 m×100 m DEM(D igital E levation Model)数据,对重庆地区降水空间分布进行研究。根据山地气候学原理,利用GIS(Geographical Information Systems)软件,分析降水空间分布的影响因子,建立平均月降水量空间估算模型,计算了平均月降水量的空间分布。结果表明:随着海拔高度的增加,降水量逐渐增加;各月降水量的最大值出现在东北山区;降水量的季节变化明显。 展开更多
关键词 降水 GIS(Geographical INFORMATION Systems) 空间分布 重庆
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AIC与BIC在亲体-补充量模型选择中的应用及比较 被引量:12
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作者 王艳君 刘群 任一平 《中国海洋大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第3期397-403,共7页
由于渔业资源评估中补充量的剧烈变动、亲体量的测量误差以及时间序列的偏差常常使亲体 补充量(SR)关系模型的确定存在很大偏差问题。本文以7种SR(Stock Recruitment)模型的模拟数据作为观测数据,研究了AIC(AkaikeInfor mationCriterion... 由于渔业资源评估中补充量的剧烈变动、亲体量的测量误差以及时间序列的偏差常常使亲体 补充量(SR)关系模型的确定存在很大偏差问题。本文以7种SR(Stock Recruitment)模型的模拟数据作为观测数据,研究了AIC(AkaikeInfor mationCriterion)与BIC(BayesianInformationCriterion)在SR模型选择中的应用。作为例证,文中采用AIC和BIC对8组实际的SR数据进行了SR模型的选择,并对其结果进行了比较。参数的估计方法为最大似然法(Maximumlikelihoodmethod)。结果表明,AIC和BIC在SR模型选择中是有效的。但是,对于嵌套模型,BIC可能比AIC更有效。 展开更多
关键词 亲体-补充量模型 最大似然法 AIC(Akaike INFORMATION Criterion) BIC(Bayesian INFORMATION Criterion)
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基于信息化的高校实验室管理创新研究 被引量:49
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作者 陈海泉 林自葵 《实验技术与管理》 CAS 北大核心 2016年第11期250-253,共4页
企业信息化的实践证明,信息化是促进管理创新、提升管理效率的有效途径。这一理论同样适用于以知识创造、人才培养为目标的高校实验室。在研究信息化与管理创新理论的基础上,分析了高校实验室面临的主要管理问题,提出了构建与实验室管... 企业信息化的实践证明,信息化是促进管理创新、提升管理效率的有效途径。这一理论同样适用于以知识创造、人才培养为目标的高校实验室。在研究信息化与管理创新理论的基础上,分析了高校实验室面临的主要管理问题,提出了构建与实验室管理创新相结合的信息化体系的解决路径,最后用北京交通大学经济管理实验中心的信息化实践结果检验了理论的有效性。 展开更多
关键词 信息化 管理创新 高校实验室 经济管理
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基于GIS的高频地波雷达回波信号的表达处理与显示 被引量:9
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作者 王瑞富 孔祥超 +3 位作者 纪永刚 徐茂景 刘楠楠 陈丽丽 《海洋科学》 CAS CSCD 北大核心 2015年第7期86-92,共7页
高频地波雷达的"距离-多普勒"(Range-Doppler,R-D)数据与"恒虚警率"(Constant False-AlarmRate,CFAR)检测结果数据存在非直观性的问题,本文针对此问题,分析了地波雷达回波数据特点以及结果形式,研究了采用地理信息... 高频地波雷达的"距离-多普勒"(Range-Doppler,R-D)数据与"恒虚警率"(Constant False-AlarmRate,CFAR)检测结果数据存在非直观性的问题,本文针对此问题,分析了地波雷达回波数据特点以及结果形式,研究了采用地理信息系统(Geographic Information System,GIS)技术对回波数据进行显示分析,对R-D与CFAR检测结果进行表达,实现高频数据在GIS环境下的表达处理与显示。本文采用GIS的栅格表达"距离-多普勒"数据,采用矢量数据结构表达CFAR检测结果,实现了地波雷达检测信息的直观显示;研究了高频地波雷达数据中特定距离一维谱信号的提取,实现了基于距离值的目标CFAR检测查询;针对雷达数据量大、处理时间长的问题,采用多线程处理机制实现了高效实时显示和分析。 展开更多
关键词 高频地波雷达 距离-多普勒 CFAR(Constant False-Alarm-Rate) 地理信息系统(Geographic Information System GIS)
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无线传感器网络中PEGASIS协议的研究与改进 被引量:13
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作者 刘伟强 蒋华 王鑫 《传感技术学报》 CAS CSCD 北大核心 2013年第12期1764-1769,共6页
针对PEGASIS协议中通信时延长、节点与节点之间存在长链、网络维护代价大的缺点,该论文在分析和仿真PEGASIS协议的基础上提出一种改进协议PEGASIS-I(PEGASIS-Improved)。该协议将监测区域看成是以基站为中心的圆形区域,基站生成参数θ... 针对PEGASIS协议中通信时延长、节点与节点之间存在长链、网络维护代价大的缺点,该论文在分析和仿真PEGASIS协议的基础上提出一种改进协议PEGASIS-I(PEGASIS-Improved)。该协议将监测区域看成是以基站为中心的圆形区域,基站生成参数θ并将圆形区域分成2π/θ个子区域,子区域内节点与节点形成通信路由树,数据先从树叶传输至树根,再由树根发送至基站。MATLAB仿真表明:与PEGASIS协议相比PEGASIS-I协议有效降低了数据传输延迟58%、避免了长链、延长了网络生存时间198%。 展开更多
关键词 PEGASIS(Power-Efficient GATHERING in SENSOR INFORMATION Systems)协议 路由树 圆形区域 PEGASIS-I协议
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近50年来广西海岸滩涂变化特征分析 被引量:13
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作者 黄鹄 陈锦辉 胡自宁 《海洋科学》 CAS CSCD 北大核心 2007年第1期37-42,共6页
作者利用不同时段的遥感影像、数字化地形图和历史航空相片,在地理信息系统平台上提取广西海岸滩涂的变化资料,并对其进行分析。结果表明,近50 a来广西海岸滩涂的变化特征为:滩涂面积经历了由加速递减(1955~1977年)、滩涂面积变化基本... 作者利用不同时段的遥感影像、数字化地形图和历史航空相片,在地理信息系统平台上提取广西海岸滩涂的变化资料,并对其进行分析。结果表明,近50 a来广西海岸滩涂的变化特征为:滩涂面积经历了由加速递减(1955~1977年)、滩涂面积变化基本不变(1978~1988年)到滩涂面积再次递减的3个阶段(1988年以来),其中滩涂面积变化最大的是沙砾质滩涂,其次是红树林滩涂,这两类滩涂面积减少最多、递减速率最快。 展开更多
关键词 滩涂 特征分析 广西海岸 遥感和GIS(Geographical INFORMATION System GIS)
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基于对数能量倒谱特征的端点检测算法 被引量:11
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作者 王民 孙广 +1 位作者 沈利荣 刘利 《计算机工程与应用》 CSCD 2014年第16期198-201,215,共5页
端点检测技术是语音识别的关键技术之一,为了克服传统倒谱距离语音端点检测算法在低信噪比下检测效果的不理想,将对数能量(LE)特征和倒谱(C)特征相结合,提出了一种新的对数能量倒谱特征(LEC),采用模糊C均值聚类和贝叶斯信息准则(BIC)方... 端点检测技术是语音识别的关键技术之一,为了克服传统倒谱距离语音端点检测算法在低信噪比下检测效果的不理想,将对数能量(LE)特征和倒谱(C)特征相结合,提出了一种新的对数能量倒谱特征(LEC),采用模糊C均值聚类和贝叶斯信息准则(BIC)方法估计特征门限,得出了正确的语音端点判断,在三种典型噪声下,对信噪比从-5 dB到15 dB的带噪声语音进行仿真,结果表明LEC法的检测错误率仅为20.25%,明显低于倒谱法和对数能量法,能有效地确定语音的端点并改善语音识别效果。 展开更多
关键词 对数能量 倒谱距离 模糊C均值聚类 贝叶斯信息准则(BIC) 端点检测 Bayesian Information Criterions(BIC)
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基于ArcEngine的海域定级系统的设计与实现 被引量:4
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作者 程敏 张秀英 +2 位作者 陈书林 卢学鹤 钟太洋 《海洋科学》 CAS CSCD 北大核心 2015年第6期88-93,共6页
海域定级是采用定性和定量的方法将同一类型用海划分为不同级别,是海域管理最基础性的工作,对于科学合理地开发和利用海岸带资源至关重要。本研究以Visual Studio 2010为开发平台,采用C语言,结合嵌入式ArcEngine组件库,集成设计实现海... 海域定级是采用定性和定量的方法将同一类型用海划分为不同级别,是海域管理最基础性的工作,对于科学合理地开发和利用海岸带资源至关重要。本研究以Visual Studio 2010为开发平台,采用C语言,结合嵌入式ArcEngine组件库,集成设计实现海洋领域具有较高专业性和实用性的海域定级系统。该系统采用海洋公益领域专家制定的指标体系,通过数据的管理、集成和分析,实现了海域定级相关方面的功能。该系统将海域定级原理与地理信息系统(Geographic Information System,GIS)技术相结合,为海域基层部门提高工作效率、实现海岸带资源科学有效管理提供了依据。 展开更多
关键词 海域定级系统 ARCENGINE 地理信息系统(Geographic INFORMATION System GIS)组件
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