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1.
先说明市内接入网的单位用户和住家用户两大类使用通信和电视、交互型和分配型业务的要求不相同,相应地对光纤传输的应用须作不同的考虑,文中认为;光纤从市内交换局直连办公大楼是合乎现实需要的,而对于居民住家,宜选用光纤连至路边或光纤与同轴结合和适当利用无源光网络等方案,俟将来时机成熟才实行光纤连至每一家,文末有概括总结,说明接入网不同于长途网,接入网的光纤系统可以使用常规单模光纤,工作于波长1.3μm,而光放大器和波分多路系统不是普遍需要,但光电子集成在光端机中是必要的。  相似文献   
2.
Interactive key frame selection model   总被引:1,自引:0,他引:1  
Video summarization can provide a fine representation of the content of video stream and reduce a large amount of data involved in video indexing, browsing, and retrieval. Moreover, Key frame selection is an important step in the research of content-based video analysis and retrieval. Although there exist a variety of methods for key frame selection, they are heuristic and closed systems, which cannot dynamically generate video summary with user’s preference. In this paper, an M-estimator and epipolar line distance constraint camera motion estimation algorithm is introduced as camera parameters is an important motion feature for key frame selection, and Broyden-Fletcher-Goldfarb-Shanno (BFGS) method is applied to optimize estimated parameters. Moreover, since Interactive Computing is a novel-computing model that represents the transition of algorithm to interaction, an interactive model of key frame selection (IKFS) is presented as a result of improving the model of key frame selection (KFS). The model of KFS and IKFS are proved to satisfy the criterion of induction and coinduction, respectively. Experimental results show that the processing scheme generates flexible and desirable summarizations whose distortion rate is lower than current method. Above all, IKFS is an extension to KFS.  相似文献   
3.
新型彩电最能集中反映显示技术的突破性进展。本文介绍全球彩电市场概况、交互式彩电、数字式彩电、数字式有线彩电及近年来不断涌现的彩电新品,如眼控式彩电、声控式彩电、声控式彩电、多媒体彩电、三维立体彩电及无荧屏彩电等。  相似文献   
4.
We prove the existence of an invariant measure for a large class of random processes with discrete time without assuming their linearity. Our main examples are “processes with variable length”, in which components may appear and disappear in the course of functioning. One of these examples displays non-uniqueness of invariant measure in a 1-D process.  相似文献   
5.
钱川 《电子测试》2014,(22):125-126,124
随着信息技术的快速发展,给教育事业的改革和发展注入了新的动力。以互联网、计算机、多媒体系统等为主的现代教学技术的应用,弥补了以往简单枯燥的灌输式教学模式,增强师生互动,有助于提升教学质量。因此,本文对美术教育中交互式电子白板的设计与实现进行深入分析。  相似文献   
6.
This paper describes progress towards developing a platform for rapid prototyping of interactive data visualizations, using R, GGobi, rggobi and RGtk2. GGobi is a software tool for multivariate interactive graphics. At the core of GGobi is a data pipeline that incrementally transforms data through a series of stages into a plot and maps user interaction with the plot back to the data. The GGobi pipeline is extensible and mutable at runtime. The rggobi package, an interface from the R language to GGobi, has been augmented with a low-level interface that supports the customization of interactive data visualizations through the extension and manipulation of the GGobi pipeline. The large size of the GGobi API has motivated the use of the RGtk2 code generation system to create the low-level interface between R and GGobi. The software is demonstrated through an application to interactive network visualization.  相似文献   
7.
Jun Wu  Ming‐Yu Lu 《ETRI Journal》2010,32(5):766-773
Support vector machine (SVM) active learning plays a key role in the interactive content‐based image retrieval (CBIR) community. However, the regular SVM active learning is challenged by what we call “the small example problem” and “the asymmetric distribution problem.” This paper attempts to integrate the merits of semi‐supervised learning, ensemble learning, and active learning into the interactive CBIR. Concretely, unlabeled images are exploited to facilitate boosting by helping augment the diversity among base SVM classifiers, and then the learned ensemble model is used to identify the most informative images for active learning. In particular, a bias‐weighting mechanism is developed to guide the ensemble model to pay more attention on positive images than negative images. Experiments on 5000 Corel images show that the proposed method yields better retrieval performance by an amount of 0.16 in mean average precision compared to regular SVM active learning, which is more effective than some existing improved variants of SVM active learning.  相似文献   
8.
Unity3d产品虚拟展示技术的研究与应用   总被引:4,自引:0,他引:4  
本文是在介绍虚拟现实技术的基础上,阐述应用专业引擎Unity3D为工具,实现虚拟产品模型展示的设计流程以及各个环节,最终开发出基于网络的,数据精准.表现力强,交互性强的工业产品虚拟展示应用系统。通过搭建一个跨越时空局限性的交流互动平台,实现企业与消费者之间更加方便快捷的产品信息交流,满足信息化时代人们对高速高效电子商务的需求。  相似文献   
9.
A multiobjective binary integer programming model for R&D project portfolio selection with competing objectives is developed when problem coefficients in both objective functions and constraints are uncertain. Robust optimization is used in dealing with uncertainty while an interactive procedure is used in making tradeoffs among the multiple objectives. Robust nondominated solutions are generated by solving the linearized counterpart of the robust augmented weighted Tchebycheff programs. A decision maker’s most preferred solution is identified in the interactive robust weighted Tchebycheff procedure by progressively eliciting and incorporating the decision maker’s preference information into the solution process. An example is presented to illustrate the solution approach and performance. The developed approach can also be applied to general multiobjective mixed integer programming problems.  相似文献   
10.
有线电视交互式自动点播系统   总被引:1,自引:0,他引:1  
介绍在现有普通有线电视基础上,增加交互式自动节目点播系统的构成方法。  相似文献   
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