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《Journal of The Franklin Institute》2023,360(12):9180-9197
The distributed estimation has important research significance in unmanned systems. This paper investigates the distributed estimation of unmanned surface vessel (USV) via multi-sensor collaboration and 3D object recognition, in which a Knowledge Graph (KG) is constructed to store and represent the estimation results. Kalman-consensus Filter (KCF) and convolutional neural network (CNN) are used to estimate the optimal states of objects, and recognise multiple classes of objects without designing detectors for each class of objects, respectively. The recognition efficiency is improved by dividing the data into pixel blocks whose value is the number of detection points, and a point cloud dataset in different locations and rotations is also provided. Experiments are proposed to show that our method can help the USV accurately perceive entities in the environment, which validates the effectiveness of the proposed algorithm. 相似文献
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为了解决云计算环境下,数字图书馆云数据中心虚拟机集群资源负载不平衡的问题,本文提出了一种云计算环境下,基于负载平衡的数字图书馆虚拟机集群资源调度策略。该策略可减少云计算环境下数字图书馆虚拟机的迁移数量,并改善云数字图书馆的用户服务质量。 相似文献
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以运行Hadoop云计算软件平台的异构机群中服务器的硬件指标作为模糊输入,设计了一种自动配置本地服务器的工具.该工具改变了传统云计算平台下的配置方法,以服务器运行历史数据作为参考,引入异构配置方法,通过对异构机群特性的分析,实现对机群的自动配置.仿真实验证明,在保证机群高效的基础上,该工具降低了云计算异构机群的维护成本,具有较高的通用性和可扩展性,对一般的云计算平台也具有参考价值. 相似文献
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基于改进特征提取及聚类的网络评论挖掘研究 总被引：1，自引：0，他引：1
[目的/意义]针对信息过载条件下中文网络产品评论中特征提取性能低以及特征聚类中初始中心点的选取问题。[方法/过程]本研究提出采用基于权重的改进Apriori算法产生候选产品特征集合,再根据独立支持度、频繁项名词非特征规则及基于网络搜索引擎的PMI算法对候选产品特征集合进行过滤。并以基于HowNet的语义相似度和特征观点共现作为衡量产品特征之间关联程度的特征,提出一种改进K-means聚类算法对产品特征进行聚类。[结果/结论]实验结果表明,在特征提取阶段,查准率为69%,查全率为92.64%,综合值达到79.07%。在特征聚类阶段,本文提出的改进K-means算法相对传统算法具有更优的挖掘性能。 相似文献
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The presence of significant multipath propagation and heavy clutter in indoor environments imposes severe limitations on imaging through walls, rendering through-the-wall radar imaging a difficult and complex proposition. It is highly desirable to properly interpret the radar images and determine the contents of the indoor scene with a high level of confidence. Data collected from multiple vantage points around a structure can be used to improve imaging visibility into the indoor scene, which, in turn, enhances indoor target detection and localization. In this paper, we consider multi-location radar imaging. Image fusion techniques for combining synthetic aperture radar images acquired from multiple locations along two sides of an enclosed structure are presented. Supporting results, based on real-data collected in a semi-controlled laboratory environment, are provided which demonstrate the improved performance of the multiple location scheme compared to operation from a single vantage point. 相似文献
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Liang Jia Junguo Zhang Shuyue Chen Zhenjie Hou 《Journal of The Franklin Institute》2018,355(15):7764-7798
Automated fabric inspection is a challenging task due to the unpredictable visual forms of the fabric defects and their scarcity compared with the tremendous amount of defect-free fabric products. This paper proposes a novel method based on lattice segmentation and lattice templates which automatically identifies the defects of fabric images. With the proposed method, a fabric image is segmented to lattices by inferring the placement rule of the texture primitives categorized to distinct texture classes. Each texture class is modeled by multiple templates inferred from the defect-free samples based on some metrics determined a priori according to their inspection efficiencies. For a lattice segmented from a given image, the most similar template is identified through a template matching process which compensates the local deformations around the lattice, and the distances between the lattice and the identified template are estimated based on the selected metrics. The lattices of distances exceeding the learnt distance range are identified as defective. The performance of the proposed method is evaluated based on two databases respectively providing pixel-level and image-level evaluations. For both databases, the receiver operating characteristic curves are plotted and the average areas under curves are 0.86 and 0.95, respectively, for pixel-level and image-level databases. The proposed method is further tested on the blurred and noisy version of images from pixel-level database and the resulting area is 0.81 on average. The proposed method outperforms the state-of-the-art methods by comparing corresponding areas. 相似文献
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《Journal of The Franklin Institute》2017,354(11):4457-4480
Due to the hopeful application of gathering information from unreachable position, wireless sensor network creates an immense challenge for data routing to maximize the communication with more energy efficiency. In order to design the energy efficient routing, the optimization based clustering protocols are more preferred in wireless sensor network. In this paper, we have proposed competent optimization based algorithm called Fractional lion (FLION) clustering algorithm for creating the energy efficient routing path. Here, the proposed clustering algorithm is used to increase the energy and lifetime of the network nodes by selecting the rapid cluster head. In addition, we have proposed multi-objective FLION clustering algorithm to develop the new fitness function based on the five objectives like intra-cluster distance, inter-cluster distance, cluster head energy, normal nodes energy and delay. Here, the proposed fitness function is used to find the rapid cluster centroid for an efficient routing path. Finally, the performance of the proposed clustering algorithm is compared with the existing clustering algorithms such as low energy adaptive clustering hierarchy (LEACH), particle swarm optimization (PSO), artificial bee colony (ABC) and Fractional ABC clustering algorithm. The results proved that the lifetime of the wireless sensor nodes is maximized by the proposed FLION based multi-objective clustering algorithm as compared with existing protocols. 相似文献
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《Information processing & management》2005,41(2):177-194
In this paper, we propose a re-ranking algorithm using post-retrieval clustering for content-based image retrieval (CBIR). In conventional CBIR systems, it is often observed that images visually dissimilar to a query image are ranked high in retrieval results. To remedy this problem, we utilize the similarity relationship of the retrieved results via post-retrieval clustering. In the first step of our method, images are retrieved using visual features such as color histogram. Next, the retrieved images are analyzed using hierarchical agglomerative clustering methods (HACM) and the rank of the results is adjusted according to the distance of a cluster from a query. In addition, we analyze the effects of clustering methods, query-cluster similarity functions, and weighting factors in the proposed method. We conducted a number of experiments using several clustering methods and cluster parameters. Experimental results show that the proposed method achieves an improvement of retrieval effectiveness of over 10% on average in the average normalized modified retrieval rank (ANMRR) measure. 相似文献
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技术创新中的供需对接加权k-平均聚类 总被引：1，自引：0，他引：1
以加权k-平均聚类方法为工具,对技术创新中的供需对接进行聚类,促进技术转化.由实际应用环境,构造抽象空间中两点的加权距离函数,通过计算空间中每个点与k个簇中心距离进行聚类,并且讨论了不同参数组合对聚类结果的影响.仿真实验表明,所建模型具有合理性和求解过程的可行性. 相似文献
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鉴于传统方法对科研成果关键词研究存在较强主观影响和较少考虑时间因素等问题,提出基于时间序列聚类的科研成果关键词分析方法。该方法通过统计分析方法验证关键词出现顺序在一定程度上反映了关键词反映主题思想的重要性,将关键词的重要度转化为时间序列数据,分别从重要度的数值和趋势两个角度出发,使用动态时间弯曲方法度量关键词重要度时间序列数据之间的相似性,结合近邻传播方法对关键词时间序列数据之间的相似性矩阵进行聚类分析,实现科研成果的关键词分析研究。通过对某科研管理类重要期刊2008—2017年期间刊发的科研成果论文关键词研究发现：新方法不仅可以对科研成果中关键词的关注热度和趋势进行聚类划分,自适应地找到中心关键词作为相应类别的特征代表对象,还能为科研成果关键词的主题分析提供理论方法和决策支持。 相似文献
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《Information processing & management》2023,60(3):103271
Because of the rapid increase of data in the cloud of Amazon Web Service (AWS), the traditional methods for analyzing this data are not good and inappropriate, so unconventional methods of analysis have been proposed by many data scientists such as concurrent/ parallel techniques to meeting the requirements of performance and scalability entailed in such big data analyses. In this paper we are used Hadoop Map Reduce system that contains Hadoop Distributed File System (HDFS) and Hadoop cluster. We optimized it by combining it with five efficient Data Mining (DM) algorithms such as Support Vector Machine (SVM), Decision Tree (DT), Random Forest (RF), Correlative Naïve Bayes classifier (CNB), and Fuzzy CNB (FCNB) for strong analytics of cloud big data. The proposed system applied on product review data that taken form the cloud of AWS. The Evaluation of Hadoop Map Reduce done with important benchmarks as Mean Absolute Percentage Error (MPAE), Root Mean Square Error (RMSE), and runtime for word count, sort, inverted index. Also, the evaluation of DM models with Hadoop Map Reduce system done by using accuracy, sensitivity, specificity, memory, and running time. Experiments have shown that FCNB is effective in addressing the problem of big data. 相似文献
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现有研究对集群企业非本地创新是否受空间距离束缚持有不同观点。立足于多维接近性视角,采用南京、西安和佛山等地114家集群企业数据,通过层次回归实证检验了地理接近性对集群企业非本地创新的影响及社会接近性的调节效应。结果显示即使考虑社会接近性,地理接近性对集群企业非本地创新绩效与创新性仍具有显著正向影响,提供了“地理未死”的直接证据。另外,表征社会接近性的四个指标中只有部分能显著调节地理接近性效应,说明社会接近性并不能完全“缓解”空间距离对集群企业非本地创新的影响,进而提供了“地理未死”的间接证据。最后,探讨了实证结果与既有理论相“冲突”的深层次原因,分析了既有研究分歧在接近性整合框架下的统一性。 相似文献
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模糊C均值(FCM)算法广泛地应用于模式识别、图像分割等领域。根据FCM算法存在对初始解敏感且迭代过程中计算量大的问题,本文提出了一种改进的算法:先通过精简数据集,减少算法迭代的时间;再使用密度函数法得到FCM算法的初始聚类中心,以减少FCM算法收敛所需的迭代次数。实验结果表明,改进后的算法较好地解决了类中心的初值化问题,提高了算法的收敛速度和运行效率。 相似文献
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In this work, the cruise control problem of high-speed trains’ movements is investigated. Both cases of a single high-speed train and multiple high-speed trains are under consideration. Different with most existing studies where the centralized control or the decentralized control methods are adopted based on a single point mass model of the train, in this paper, a distributed control mechanism is proposed by virtue of the graph theory, and the high-speed train’s model is built as a cascade of point masses connected by flexible couplers. For a single high-speed train, the neighboring cars interact through the coupling force with each other, which can be described by a connected topological graph by regarding each car as a node. Besides, the speed information communication among the cars is considered to be described by another directed topological graph. A distributed control strategy is then developed, with which all the cars of a train track a desired speed asymptotically and the neighboring cars keep a safety distance from each other. For the multiple high-speed trains running on a railway line, the in-train force interaction topology and the speed information communication topology of all the trains are more complex than those of a single train. A new cluster consensus technique is developed, by which a distributed control law is designed. Under the control law, the trains can track the desired speeds asymptotically, the headway distance between adjacent trains and the distance between the neighboring cars of a train can be kept in appropriate ranges. Finally, simulations are provided to illustrate the effectiveness of the obtained theoretical results. 相似文献
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Goktug T. Cinar Pedro M.N. Sequeira Jose C. Principe 《Journal of The Franklin Institute》2018,355(4):1638-1662
In this paper we develop a new framework for time series segmentation based on a Hierarchical Linear Dynamical System (HLDS), and test its performance on monophonic and polyphonic musical note recognition. The center piece of our approach is the inclusion of constraints in the filter topology, instead of on the cost function as normally done in machine learning. Just by slowing down the dynamics of the top layer of an augmented (multilayer) state model, which is still compatible with the recursive update equation proposed originally by Kalman, the system learns directly from data all the musical notes, without labels, effectively creating a time series clustering algorithm that does not require segmentation. We analyze the HLDS properties and show that it provides better classification accuracy compared to current state-of-the-art approaches. 相似文献
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1991-2011年南海周边国家及地区经济重心及经济发展重心演变分析 总被引：2，自引：0，他引：2
运用重心模型,计算出1991-2011年间南海周边国家及地区经济重心及经济发展重心坐标,揭示南海周边国家及地区经济特征演变过程。研究结果表明:①总体上看,以区域几何中心为参照,经济重心大体呈南北狭长型分布,全部落于区域东北部位置,经济发展重心大体呈团聚状分布,有11个落入东北部,10个落入西北部;②在整体移动轨迹方面,经济重心比经济发展重心表现出更为简洁的特征,2000年后经济重心稳定向西南方向移动,经济发展重心在短时间内会呈现急剧的变化,这说明经济重心存在来自于区域特定方向上的力的强烈作用,而经济发展重心来自于经度和纬度方向上的力都较为均衡;③1999年以后,来自区域西部方向的力持续稳定地拉动经济重心的移动,区域南部的力对经济重心移动极为显著。同时,对经济发展重心而言,1999年后东西方向上的力对其移动作用不显著,在南北方向上有悄然北移的态势;④从区域经济总量和经济发展水平均衡性来看,经济重心在总体上趋于稳定态势,经济发展重心的不均衡性逐渐加强并稳定,且来自于南北方向上的力是造成这种结果的主要原因。 相似文献