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1.
特征间互补性结合使用的3D模型检索技术   总被引:1,自引:0,他引:1       下载免费PDF全文
三维(3D)模型检索是多媒体信息检索的热点研究问题之一。针对基于单一形状特征的3D模型检索存在 的不足,提出了结合多种形状特征进行模型检索的方法。把模型的面积分布和纬度方向平均半径2种特征被应用 于模型检索。实验结果表明,由于不同形状特征的互补性,采用多种形状特征可以得到更好的检索准确率。  相似文献   

2.
三维(3D)模型检索是多媒体信息检索的热点研究问题之一。针对基于单一形状特征的3D模型检索存在的不足,提出了结合多种形状特征进行模型检索的方法。把模型的面积分布和纬度方向平均半径2种特征被应用于模型检索。实验结果表明,由于不同形状特征的互补性,采用多种形状特征可以得到更好的检索准确率。  相似文献   

3.
基于内容的图像特征相关性检索方法   总被引:4,自引:0,他引:4  
针对目前基于内容的图像检索系统在模型优化及通用性设计等方面的局限性,以图像单一特征描述和提取方法为基础,根据人机交互的相关反馈原理,分析图像组合特征归一化权值系数,提出一套图像特征相关性检索新方案,并在着重对基于内容的图像特征相关性检索算法研究基础上,参照国际标准MPEG-7所提供的通用性系统设计规范,对新方案下的图像检索通用模型进行概念设计,为解决基于内容的图像检索技术在Internet上实用化的瓶颈问题,提供一条新的思路,实验结果验证了新方案的合理性。  相似文献   

4.
针对一般基于案例属性相似度的案例检索方法在实际应用时存在相似性度量的定义等难点而无法保证两效、准确检索的问题。提出了一种新的案例检索方法。根据粗糙集理论对冷轧负荷分配决策表进行简约以及从简约的决策表数据中发现规则,在此基础上利用发现的规则建立隐层节点数更合理的神经网络模型。以此神经网络模型实现相似案例检索,经在线实验证明,应用该方法可实现快速高效的案例检索。提高了整体智能推理建模的效率和质量。  相似文献   

5.
通过分析3D交互式网购体验系统的体系架构与功能模块,利用Flash3D、RIA、web即时通信、基于图像的3D模型检索等技术实现Web环境下的3D交互式网购体验系统,并对系统的性能、应用效果、应用成本及其影响因素进行讨论.  相似文献   

6.
为提高三维(Three dimensional, 3D)打印机械零件生产方式的生产效率和产品质量,研究提出一个改进的光固化立体造型术(Stereolithography, STL)模型分层算法,该算法采用层厚关联方式对STL模型进行同步分块处理,并结合三角网格面片的顶点信息与法向量信息重构邻接拓扑关系,形成切片平面的网格面片环,并以此为基础对STL模型进行优化分层切片。实验结果显示,该算法在分层厚度为0.30mm条件下的分层算法轮廓算术平均偏差均值为0.77,平均计算耗时为2.45s,均明显优于目前行业内常用的分层算法。实验结果证明,此次设计的改进STL模型分层算法在复杂机械零件3D打印生产中具有一定的应用前景,并能起到加快零件生产速度、提高打印产品表面光滑度的作用。  相似文献   

7.
为了捕捉自传体记忆,提出了一种针对自传体记忆的计算AM模型.模型为3层网络结构.底层由5W1H构成的特定事件知识进行编码,提供检索线索;中间层通过关联特定事件知识对事件进行编码;顶层通过关联相关事件对事件集进行编码.按照自下而上的记忆搜索过程,AM模型可以分别在中间层和顶层识别相应的事件和事件集,同时,还能通过规则记忆检索过程模仿人在回忆中漫游的现象.基于一组数据集的实验结果表明,模型不仅具有鲁棒的、灵活的记忆检索,而且相较于普遍采用的基于关键字的查询方法记忆检索模型,对含噪记忆检索线索有更好的响应性能,还能够模仿回忆中的漫游现象.  相似文献   

8.
为解决程序调试过程中的错误定位问题, 将程序执行轨迹和动态切片技术应用于错误定位。程序执行轨迹中包含与错误无关语句, 影响错误定位的准确度。在执行轨迹的基础上, 通过使用动态切片技术降低不相关语句在错误定位时的影响。建立基于程序执行轨迹和动态切片的语句怀疑度计算模型, 使用该模型计算每条语句的怀疑度, 并根据怀疑度对每条语句进行排序, 给出查错的推荐方案。通过实验对比其他算法, 证明了基于程序执行轨迹与动态切片的错误定位方法是有效的。  相似文献   

9.
为了解决基于内容的图像检索(content-Based Image Retrieval,CBIR)中存在的“语义鸿沟”问题,本文提出了一种CBIR检索模型,在模型中使用了基于近邻传播的半监督聚类算法和语义传播的算法,通过近邻半监督算法对图像库中的图像进行聚类,根据示例图像的视觉特征相似度在对应的聚类图像中进行相似度检索,在检索的结果中根据用户提供的关键字进行关键字标注检索,最后根据用户的反馈,通过语义传播算法对图像库中的图像进行自动语义标注.实验表明丈中的模型是可行的,其检索效果受到反馈次数的影响.  相似文献   

10.
针对传统自整合信息检索方法在对图书自整合信息进行检索时, 存在检索结果不准确和效率低的问题, 提出一种基于Top-k查询算法的图书自整合信息快速检索方法. 首先利用Top-k查询算法对去噪后的自整合信息进行匹配, 然后建立自整合信息快速检索模型, 根据词意的重要性对图书自整合信息进行快速检索. 仿真实验结果表明, 该方法检索性能较好, 缩短了整体运行所需时间, 提升了检索效率, 且检索结果更准确.  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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