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Training of Multi-layered Neural Network for Data Enlargement Processing Using an Activity Function 被引量:1
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作者 Betere Job Isaac Hiroshi Kinjo +1 位作者 Kunihiko Nakazono Naoki Oshiro 《Journal of Electrical Engineering》 2019年第1期1-7,共7页
In this paper, we present a study on activity functions for an MLNN (multi-layered neural network) and propose a suitable activity function for data enlargement processing. We have carefully studied the training perfo... In this paper, we present a study on activity functions for an MLNN (multi-layered neural network) and propose a suitable activity function for data enlargement processing. We have carefully studied the training performance of Sigmoid, ReLu, Leaky-ReLu and L & exp. activity functions for few inputs to multiple output training patterns. Our MLNNs model has L hidden layers with two or three inputs to four or six outputs data variations by BP (backpropagation) NN (neural network) training. We focused on the multi teacher training signals to investigate and evaluate the training performance in MLNNs to select the best and good activity function for data enlargement and hence could be applicable for image and signal processing (synaptic divergence) along with the proposed methods with convolution networks. We specifically used four activity functions from which we found out that L & exp. activity function can suite DENN (data enlargement neural network) training since it could give the highest percentage training abilities compared to the other activity functions of Sigmoid, ReLu and Leaky-ReLu during simulation and training of data in the network. And finally, we recommend L & exp. function to be good for MLNNs and may be applicable for signal processing of data and information enlargement because of its performance training characteristics with multiple teacher training patterns using original generated data and hence can be tried with CNN (convolution neural networks) of image processing. 展开更多
关键词 data ENLARGEMENT processing MLNN ACTIVITY FUNCTION multi teacher TRAINING signals BP NN CNN
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Multi-dimensional database design and implementation of dam safety monitoring system 被引量:1
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作者 Zhao Erfeng Wang Yachao +2 位作者 Jiang Yufeng Zhang Lei Yu Hong 《Water Science and Engineering》 EI CAS 2008年第3期112-120,共9页
To improve the effectiveness of dam safety monitoring database systems, the development process of a multi-dimensional conceptual data model was analyzed and a logic design wasachieved in multi-dimensional database mo... To improve the effectiveness of dam safety monitoring database systems, the development process of a multi-dimensional conceptual data model was analyzed and a logic design wasachieved in multi-dimensional database mode. The optimal data model was confirmed by identifying data objects, defining relations and reviewing entities. The conversion of relations among entities to external keys and entities and physical attributes to tables and fields was interpreted completely. On this basis, a multi-dimensional database that reflects the management and analysis of a dam safety monitoring system on monitoring data information has been established, for which factual tables and dimensional tables have been designed. Finally, based on service design and user interface design, the dam safety monitoring system has been developed with Delphi as the development tool. This development project shows that the multi-dimensional database can simplify the development process and minimize hidden dangers in the database structure design. It is superior to other dam safety monitoring system development models and can provide a new research direction for system developers. 展开更多
关键词 dam safety multi-dimensional database conceptual data model database mode monitoring system
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Goodness-of-fit tests for multi-dimensional copulas:Expanding application to historical drought data 被引量:2
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作者 Ming-wei MA Li-liang REN +2 位作者 Song-bai SONG Jia-li SONG Shan-hu JIANG 《Water Science and Engineering》 EI CAS CSCD 2013年第1期18-30,共13页
The question of how to choose a copula model that best fits a given dataset is a predominant limitation of the copula approach, and the present study aims to investigate the techniques of goodness-of-fit tests for mul... The question of how to choose a copula model that best fits a given dataset is a predominant limitation of the copula approach, and the present study aims to investigate the techniques of goodness-of-fit tests for multi-dimensional copulas. A goodness-of-fit test based on Rosenblatt's transformation was mathematically expanded from two dimensions to three dimensions and procedures of a bootstrap version of the test were provided. Through stochastic copula simulation, an empirical application of historical drought data at the Lintong Gauge Station shows that the goodness-of-fit tests perform well, revealing that both trivariate Gaussian and Student t copulas are acceptable for modeling the dependence structures of the observed drought duration, severity, and peak. The goodness-of-fit tests for multi-dimensional copulas can provide further support and help a lot in the potential applications of a wider range of copulas to describe the associations of correlated hydrological variables. However, for the application of copulas with the number of dimensions larger than three, more complicated computational efforts as well as exploration and parameterization of corresponding copulas are required. 展开更多
关键词 goodness-of-fit test multi-dimensional copulas stochastic simulation Rosenblatt'stransformation bootstrap approach drought data
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Multidimensional Data Querying on Tree-Structured Overlay
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作者 XU Lizhen WANG Shiyuan 《Wuhan University Journal of Natural Sciences》 CAS 2006年第5期1367-1372,共6页
Multidimensional data query has been gaining much interest in database research communities in recent years, yet many of the existing studies focus mainly on ten tralized systems. A solution to querying in Peer-to-Pee... Multidimensional data query has been gaining much interest in database research communities in recent years, yet many of the existing studies focus mainly on ten tralized systems. A solution to querying in Peer-to-Peer(P2P) environment was proposed to achieve both low processing cost in terms of the number of peers accessed and search messages and balanced query loads among peers. The system is based on a balanced tree structured P2P network. By partitioning the query space intelligently, the amount of query forwarding is effectively controlled, and the number of peers involved and search messages are also limited. Dynamic load balancing can be achieved during space partitioning and query resolving. Extensive experiments confirm the effectiveness and scalability of our algorithms on P2P networks. 展开更多
关键词 range query skyline query P2P indexing multi-dimensional data partition
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Image Processing on Geological Data in Vector Format and Multi-Source Spatial Data Fusion
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作者 Liu Xing Hu Guangdao Qiu Yubao Faculty of Earth Resources, China University of Geosciences, Wuhan 430074 《Journal of China University of Geosciences》 SCIE CSCD 2003年第3期278-282,共5页
The geological data are constructed in vector format in geographical information system (GIS) while other data such as remote sensing images, geographical data and geochemical data are saved in raster ones. This paper... The geological data are constructed in vector format in geographical information system (GIS) while other data such as remote sensing images, geographical data and geochemical data are saved in raster ones. This paper converts the vector data into 8 bit images according to their importance to mineralization each by programming. We can communicate the geological meaning with the raster images by this method. The paper also fuses geographical data and geochemical data with the programmed strata data. The result shows that image fusion can express different intensities effectively and visualize the structure characters in 2 dimensions. Furthermore, it also can produce optimized information from multi-source data and express them more directly. 展开更多
关键词 geological data GIS-based vector data conversion image processing multi-source data fusion
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Dimensionality Reduction of High-Dimensional Highly Correlated Multivariate Grapevine Dataset
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作者 Uday Kant Jha Peter Bajorski +3 位作者 Ernest Fokoue Justine Vanden Heuvel Jan van Aardt Grant Anderson 《Open Journal of Statistics》 2017年第4期702-717,共16页
Viticulturists traditionally have a keen interest in studying the relationship between the biochemistry of grapevines’ leaves/petioles and their associated spectral reflectance in order to understand the fruit ripeni... Viticulturists traditionally have a keen interest in studying the relationship between the biochemistry of grapevines’ leaves/petioles and their associated spectral reflectance in order to understand the fruit ripening rate, water status, nutrient levels, and disease risk. In this paper, we implement imaging spectroscopy (hyperspectral) reflectance data, for the reflective 330 - 2510 nm wavelength region (986 total spectral bands), to assess vineyard nutrient status;this constitutes a high dimensional dataset with a covariance matrix that is ill-conditioned. The identification of the variables (wavelength bands) that contribute useful information for nutrient assessment and prediction, plays a pivotal role in multivariate statistical modeling. In recent years, researchers have successfully developed many continuous, nearly unbiased, sparse and accurate variable selection methods to overcome this problem. This paper compares four regularized and one functional regression methods: Elastic Net, Multi-Step Adaptive Elastic Net, Minimax Concave Penalty, iterative Sure Independence Screening, and Functional Data Analysis for wavelength variable selection. Thereafter, the predictive performance of these regularized sparse models is enhanced using the stepwise regression. This comparative study of regression methods using a high-dimensional and highly correlated grapevine hyperspectral dataset revealed that the performance of Elastic Net for variable selection yields the best predictive ability. 展开更多
关键词 HIGH-dimensional data multi-STEP Adaptive Elastic Net MINIMAX CONCAVE Penalty Sure Independence Screening Functional data Analysis
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Research of a New Multi-dimensional Dataset Search Framework on Unstructured P2P
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作者 DENG Hui-min ZENG Bi-qing XIA Xu 《通讯和计算机(中英文版)》 2007年第1期1-7,共7页
关键词 复合型数据 数据挖掘 P2P系统 数据询问
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Finding Main Causes of Elevator Accidents via Multi-Dimensional Association Rule in Edge Computing Environment 被引量:2
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作者 Hongman Wang Mengqi Zeng +1 位作者 Zijie Xiong Fangchun Yang 《China Communications》 SCIE CSCD 2017年第11期39-47,共9页
In order to discover the main causes of elevator group accidents in edge computing environment, a multi-dimensional data model of elevator accident data is established by using data cube technology, proposing and impl... In order to discover the main causes of elevator group accidents in edge computing environment, a multi-dimensional data model of elevator accident data is established by using data cube technology, proposing and implementing a method by combining classical Apriori algorithm with the model, digging out frequent items of elevator accident data to explore the main reasons for the occurrence of elevator accidents. In addition, a collaborative edge model of elevator accidents is set to achieve data sharing, making it possible to check the detail of each cause to confirm the causes of elevator accidents. Lastly the association rules are applied to find the law of elevator Accidents. 展开更多
关键词 elevator group accidents APRIORI multi-dimensional association rules data cube edge computing
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Augmented Industrial Data-Driven Modeling Under the Curse of Dimensionality
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作者 Xiaoyu Jiang Xiangyin Kong Zhiqiang Ge 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第6期1445-1461,共17页
The curse of dimensionality refers to the problem o increased sparsity and computational complexity when dealing with high-dimensional data.In recent years,the types and vari ables of industrial data have increased si... The curse of dimensionality refers to the problem o increased sparsity and computational complexity when dealing with high-dimensional data.In recent years,the types and vari ables of industrial data have increased significantly,making data driven models more challenging to develop.To address this prob lem,data augmentation technology has been introduced as an effective tool to solve the sparsity problem of high-dimensiona industrial data.This paper systematically explores and discusses the necessity,feasibility,and effectiveness of augmented indus trial data-driven modeling in the context of the curse of dimen sionality and virtual big data.Then,the process of data augmen tation modeling is analyzed,and the concept of data boosting augmentation is proposed.The data boosting augmentation involves designing the reliability weight and actual-virtual weigh functions,and developing a double weighted partial least squares model to optimize the three stages of data generation,data fusion and modeling.This approach significantly improves the inter pretability,effectiveness,and practicality of data augmentation in the industrial modeling.Finally,the proposed method is verified using practical examples of fault diagnosis systems and virtua measurement systems in the industry.The results demonstrate the effectiveness of the proposed approach in improving the accu racy and robustness of data-driven models,making them more suitable for real-world industrial applications. 展开更多
关键词 Index Terms—Curse of dimensionality data augmentation data-driven modeling industrial processes machine learning
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Outlier detection based on multi-dimensional clustering and local density
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作者 SHOU Zhao-yu LI Meng-ya LI Si-min 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第6期1299-1306,共8页
Outlier detection is an important task in data mining. In fact, it is difficult to find the clustering centers in some sophisticated multidimensional datasets and to measure the deviation degree of each potential outl... Outlier detection is an important task in data mining. In fact, it is difficult to find the clustering centers in some sophisticated multidimensional datasets and to measure the deviation degree of each potential outlier. In this work, an effective outlier detection method based on multi-dimensional clustering and local density(ODBMCLD) is proposed. ODBMCLD firstly identifies the center objects by the local density peak of data objects, and clusters the whole dataset based on the center objects. Then, outlier objects belonging to different clusters will be marked as candidates of abnormal data. Finally, the top N points among these abnormal candidates are chosen as final anomaly objects with high outlier factors. The feasibility and effectiveness of the method are verified by experiments. 展开更多
关键词 data MINING OUTLIER DETECTION OUTLIER DETECTION method based on multi-dimensional CLUSTERING and local density (ODBMCLD) algorithm deviation DEGREE
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MULTI-DIMENSIONAL MARKOV CHAIN–BASED ANALYSIS OF CONFLICT PROBABILITY FOR SPECTRUM RESOURCE SHARING
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作者 张轶 喻莉 张利维 《Acta Mathematica Scientia》 SCIE CSCD 2015年第1期207-215,共9页
In this paper, we consider the optimal problem of channels sharing with het-erogeneous traffic (real-time service and non-real-time service) to reduce the data conflict probability of users. Moreover, a multi-dimens... In this paper, we consider the optimal problem of channels sharing with het-erogeneous traffic (real-time service and non-real-time service) to reduce the data conflict probability of users. Moreover, a multi-dimensional Markov chain model is developed to analyze the performance of the proposed scheme. Meanwhile, performance metrics are derived. Numerical results show that the proposed scheme can effectively reduce the forced termination probability, blocking probability and spectrum utilization. 展开更多
关键词 multi-dimensional Markov chain model independent Poisson process negative exponential distribution forced termination probability blocking probability
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Multi-relaxation-time lattice Boltzmann simulations of lid driven flows using graphics processing unit
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作者 Chenggong LI J.P.Y.MAA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第5期707-722,共16页
Large eddy simulation (LES) using the Smagorinsky eddy viscosity model is added to the two-dimensional nine velocity components (D2Q9) lattice Boltzmann equation (LBE) with multi-relaxation-time (MRT) to simul... Large eddy simulation (LES) using the Smagorinsky eddy viscosity model is added to the two-dimensional nine velocity components (D2Q9) lattice Boltzmann equation (LBE) with multi-relaxation-time (MRT) to simulate incompressible turbulent cavity flows with the Reynolds numbers up to 1 × 10^7. To improve the computation efficiency of LBM on the numerical simulations of turbulent flows, the massively parallel computing power from a graphic processing unit (GPU) with a computing unified device architecture (CUDA) is introduced into the MRT-LBE-LES model. The model performs well, compared with the results from others, with an increase of 76 times in computation efficiency. It appears that the higher the Reynolds numbers is, the smaller the Smagorinsky constant should be, if the lattice number is fixed. Also, for a selected high Reynolds number and a selected proper Smagorinsky constant, there is a minimum requirement for the lattice number so that the Smagorinsky eddy viscosity will not be excessively large. 展开更多
关键词 large eddy simulation (LES) multi-relaxation-time (MRT) lattice Boltzmann equation (LBE) two-dimensional nine velocity components (D2Q9) Smagorinskymodel graphic processing unit (GPU) computing unified device architecture (CUDA)
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Design and Realization of Block Level Augmented Reality Three-Dimensional Map
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作者 Dashuai Shang Chenguang Dai +1 位作者 Ying Yu Yabing Fan 《Journal of Computer and Communications》 2023年第6期113-121,共9页
In response to the construction needs of “Real 3D China”, the system structure, functional framework, application direction and product form of block level augmented reality three-dimensional map is designed. Those ... In response to the construction needs of “Real 3D China”, the system structure, functional framework, application direction and product form of block level augmented reality three-dimensional map is designed. Those provide references and ideas for the later large-scale production of augmented reality three-dimensional map. The augmented reality three-dimensional map is produced based on skyline software. Including the map browsing, measurement and analysis and so on, the basic function of three-dimensional map is realized. The special functional module including housing management, pipeline management and so on is developed combining the need of residential quarters development, that expands the application fields of augmented reality three-dimensional map. Those lay the groundwork for the application of augmented reality three-dimensional map. . 展开更多
关键词 Augmented Reality Three-dimensional Map multi-Source data Fusion Three-dimensional Analysis Three-dimensional Scene SKYLINE
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基于Multi-agent技术的Web文本挖掘模型及应用 被引量:3
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作者 姜丽华 黄敏 +1 位作者 马永光 佟振声 《计算机工程》 EI CAS CSCD 北大核心 2005年第1期217-218,221,共3页
介绍了一个基于Multi-agent技术的Web文本挖掘模型,该模型利用多智能体技术,将文本挖掘和多维文件分析技术结合起来实现了文档收集、预处理、分类、聚类等功能。最后给出了根据该模型设计和实现的某企业人才素质评价系统的实例,系统运... 介绍了一个基于Multi-agent技术的Web文本挖掘模型,该模型利用多智能体技术,将文本挖掘和多维文件分析技术结合起来实现了文档收集、预处理、分类、聚类等功能。最后给出了根据该模型设计和实现的某企业人才素质评价系统的实例,系统运行结果证明了模型的有效性和科学性。 展开更多
关键词 multi-AGENT 自然语言处理 数据挖掘 文本挖掘
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基于OpenMP的遥感影像并行ISODATA聚类研究 被引量:11
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作者 刘扬 王鹏 +4 位作者 杨瑞 左宪禹 张周威 吴晓洋 渠涧涛 《计算机工程》 CAS CSCD 北大核心 2016年第7期238-243,250,共7页
针对传统影像分类算法执行效率较低,无法满足海量高分辨率遥感数据实时处理需求的问题,对资源三号卫星专题产品中遥感影像的迭代自组织数据分析算法进行分析与研究,设计一种基于OpenMP的并行ISODATA聚类算法(PIsodata Omp)。采用OpenMP... 针对传统影像分类算法执行效率较低,无法满足海量高分辨率遥感数据实时处理需求的问题,对资源三号卫星专题产品中遥感影像的迭代自组织数据分析算法进行分析与研究,设计一种基于OpenMP的并行ISODATA聚类算法(PIsodata Omp)。采用OpenMP技术优化ISODATA算法中的样本点聚类、聚类样本中心标准差计算,实现基于共享内存的单机多核并行化处理。实验结果表明,PIsodata Omp算法能在保证分类精度不变的情况下,明显提高资源三号卫星影像数据的处理速度。 展开更多
关键词 并行聚类 迭代自组织数据分析算法 OpenMP技术 遥感影像分类 多核处理
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基于Multi-Agent的数字化矿山配电网保护方法 被引量:2
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作者 王波 赵涛 李梦超 《陕西煤炭》 2016年第4期101-103,共3页
给出一种基于Multi-Agent的数字化矿山配电网保护方法。将数字化矿山配电终端IDT和控制中心分别作为一个Agent,通过通信网络使得所有Agent组成Multi-Agent系统。各Agent通过信息交互,实现数字化矿山配电网的继电保护、故障定位,故障隔离... 给出一种基于Multi-Agent的数字化矿山配电网保护方法。将数字化矿山配电终端IDT和控制中心分别作为一个Agent,通过通信网络使得所有Agent组成Multi-Agent系统。各Agent通过信息交互,实现数字化矿山配电网的继电保护、故障定位,故障隔离,故障诊断等功能。保护方法采用数据并行处理方式来节省数据所需带宽同时提高了数据的处理速度。 展开更多
关键词 数字化矿山 multi-AGENT 线路保护 数据并行处理
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FAAD:an unsupervised fast and accurate anomaly detection method for a multi-dimensional sequence over data stream 被引量:1
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作者 Bin LI Yi-jie WANG +2 位作者 Dong-sheng YANG Yong-mou LI Xing-kong MA 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2019年第3期388-404,共17页
Recently, sequence anomaly detection has been widely used in many fields. Sequence data in these fields are usually multi-dimensional over the data stream. It is a challenge to design an anomaly detection method for a... Recently, sequence anomaly detection has been widely used in many fields. Sequence data in these fields are usually multi-dimensional over the data stream. It is a challenge to design an anomaly detection method for a multi-dimensional sequence over the data stream to satisfy the requirements of accuracy and high speed. It is because:(1) Redundant dimensions in sequence data and large state space lead to a poor ability for sequence modeling;(2) Anomaly detection cannot adapt to the high-speed nature of the data stream, especially when concept drift occurs, and it will reduce the detection rate. On one hand, most existing methods of sequence anomaly detection focus on the single-dimension sequence. On the other hand, some studies concerning multi-dimensional sequence concentrate mainly on the static database rather than the data stream. To improve the performance of anomaly detection for a multi-dimensional sequence over the data stream, we propose a novel unsupervised fast and accurate anomaly detection(FAAD) method which includes three algorithms. First, a method called "information calculation and minimum spanning tree cluster" is adopted to reduce redundant dimensions. Second, to speed up model construction and ensure the detection rate for the sequence over the data stream, we propose a method called"random sampling and subsequence partitioning based on the index probabilistic suffix tree." Last, the method called "anomaly buffer based on model dynamic adjustment" dramatically reduces the effects of concept drift in the data stream. FAAD is implemented on the streaming platform Storm to detect multi-dimensional log audit data.Compared with the existing anomaly detection methods, FAAD has a good performance in detection rate and speed without being affected by concept drift. 展开更多
关键词 data STREAM multi-dimensional SEQUENCE ANOMALY detection Concept DRIFT Feature selection
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Algorithm for Multi-laser-target Tracking Based on Clustering Fusion
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作者 张立群 李言俊 张科 《Defence Technology(防务技术)》 SCIE EI CAS 2007年第1期28-32,共5页
Multi-laser-target tracking is an important subject in the field of signal processing of laser warners. A clustering method is applied to the measurement of laser warner, and the space-time fusion for measurements in ... Multi-laser-target tracking is an important subject in the field of signal processing of laser warners. A clustering method is applied to the measurement of laser warner, and the space-time fusion for measurements in the same cluster is accomplished. Real-time tracking of multi-laser-target and real-time picking of multi-laser-signal are introduced using data fusion of the measurements. A prototype device of the algorithm is built up. The results of experiments show that the algorithm is very effective. 展开更多
关键词 激光报警器 多目标跟踪 算法 聚类融合 信息处理
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On Numerical methods for determination of Earth gravity field model using mass satellite gravity gradiometry data
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作者 Zhu Guangbin Chang Xiaotao +2 位作者 Li Xinfa Zhang Xinhang Li Yuxing 《Geodesy and Geodynamics》 2012年第1期57-62,共6页
On the basis of Space-Wise Least Square method, three numerical methods including Cholesky de- composition, pre-conditioned conjugate gradient and Open Multi-Processing parallel algorithm are applied into the determin... On the basis of Space-Wise Least Square method, three numerical methods including Cholesky de- composition, pre-conditioned conjugate gradient and Open Multi-Processing parallel algorithm are applied into the determination of gravity field with satellite gravity gradiometry data. The results show that, Cholesky de- composition method has been unable to meet the requirements of computation efficiency when the computer hardware is limited. Pre-conditioned conjugate gradient method can improve the computation efficiency of huge matrix inversion, but it also brings a certain loss of precision. The application of Open Multi-Processing parallel algorithm could achieve a good compromise between accuracy and computation efficiency. 展开更多
关键词 satellite gravity gradiometry Cholesky decomposition pre-conditioned conjugate gradient open multi-processing parallel algorithm data processing
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基于OBE的数据结构多维融合教学模式实践 被引量:1
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作者 李征 乔保军 +2 位作者 杨伟 袁彩虹 刘成 《软件导刊》 2024年第2期162-166,共5页
在工程教育专业认证背景下,为了开展“以学生为中心、以产出为导向”的数据结构教学,借助现代信息技术构建线上线下、课内课外以及理论实践多维融合的教学模式。该教学模式以OBE理念为指导进行混合式教学及考核评价方法设计,并基于翻转... 在工程教育专业认证背景下,为了开展“以学生为中心、以产出为导向”的数据结构教学,借助现代信息技术构建线上线下、课内课外以及理论实践多维融合的教学模式。该教学模式以OBE理念为指导进行混合式教学及考核评价方法设计,并基于翻转课堂有效整合不同维度的学习活动,激发学生自主学习的积极性,拓展学生的知识体系。目前,该教学模式已面向河南大学计算机科学与技术专业进行了3个学期的教学实践,从学生、专家的反馈情况及课程目标达成情况来看,教学效果明显,多维融合教学模式有效提升了学生的自主学习能力、分析与解决实际问题能力以及拓展创新能力。 展开更多
关键词 OBE 数据结构 混合式教学 多维度考核
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