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1.
The difficulties in the transmission of streaming media are analyzed, the packet scheduling on the streaming media server is studied. A Markov model is proposed under the effect of the complex dependency among the streaming media packets and the parameters of the transmission channel. On the basis of the Markov model,a policy is made to queue the streaming media packets in the sending buffer by using the iteration method, which can optimize the playback quality under the lack of the channel bandwidth.  相似文献   

2.
A real time mixing module for high definition television (HDTV) data of SMPTE 274M and PC video data is designed. The hardware implementation, algorithm and simulation of the mixing module are given. In order to improve the capability of data processing, an anti-fuse FPGA chip and a mechanism of pipelining and modularization are adopted. With 6 parallel LUTs and a fast algorithm, it can mix 4:2:2 component signals in luminance and chrominance space respectively in real time. According to the simulation, the module has the ability to mix the uncompressed HDTV data with PC video data in real time, which can not be fulfilled by current ASIC chips. Furthermore, it can be extended to multi-stage mixing with the thoughts implied by the design. The mixing module can be widely used in HDTV production systems.  相似文献   

3.
In order to realize the explorer autonomy, the software architecture of autonomous mission management system (AMMS) is given for the deep space explorer, and the autonomous mission planning system, the kernel part of this architecture, is designed in detail. In order to describe the parallel activity, the state timeline is introduced to build the formal model of the planning system and based on this model, the temporal constraint satisfaction planning algorithm is proposed to produce the explorer‘ s activity sequence. With some key subsystems of the deep space explorer as examples, the autonomous mission planning simulation system is designed.The results show that this system can calculate the executable activity sequence with the given mission goals and initial state of the explorer.  相似文献   

4.
A large number of spatial and attribute data are involved in coal resource evaluation. Database is a relatively advanced data management technology, but its Major defects are the poor graphic and spatial data functions, from which it is difficult to realize scientific management of evaluation data with spatial characteristics and evaluation result maps. On account of these deficiencies, the evaluation of degree of complexity of mining fault network, based on GIS, is proposed, which integrates management of spatial and attribute data. Fractal is an index which can reflect the comprehensive information of faults' number, density, size, composition and dynamics mechanism. Fractal dimension is used as the quantitative evaluation index. Evaluation software has been developed based on a component GIS-MapX, with which the degree of complexity of fault network is evaluated quantitatively using the quantitative index of fractal dimensions in Liuqiao No.2 coal mine as an example. Results show that it is effective in acquiring model parameters and enhancing the definition of data and evaluation results with the application of GIS technology. The fault network is a system with fractal structure and its complexity can be described reasonably and accurately by fractal dimension, which provides an effective method for coal resource evaluation.  相似文献   

5.
With the continuous development of cloud manufacturing technology,in order to solve more complex manufacturing problem and conduct large-scale networked manufacturing,combining with the characteristic of discrete manufacturing enterprise's demands and RFID( Radio Frequency Identification),a kind of RFIDbased cloud manufacturing resource-aware and access technology is proposed. Firstly,the architecture of the cloud manufacturing system and RFID system is briefly introduced. Then,the key technologies of manufacturing resource-aware and access technology are analyzed,including anti-collision technology,reader management technology and so on. Finally,taking the manufacturing of the key components in discrete manufacturing enterprise as an example,the practicality and feasibility of the technology is verified. The results show that the application of this technology provides a strong guarantee for the sharing and collaboration of manufacturing resources and capacity in the discrete manufacturing industry.  相似文献   

6.
An object segment similarity function is taken into account from the continuous media frames to measure the individual streaming profit of certain segment versions of a media object.Therefore,a new segment version-based transcoding (SVT) mechanism is derived for a quality of service (QoS) of client-centric media streaming in wireless mobile networks.The derived function utilizes the fuzzy similarity of certain segment versions of an object.This mechanism provides the effectiveness of reduction of the stream startup latency among segment versions,and the average access of each version.Thus,the proposed segment version transcoding mechanism reduces packet loss which in turn increases streaming performance and throughput.The performance of the partitioned segment versions is simulated and some segment versions are completed.The simulation results show that the proposed mechanism outperforms the other mechanisms in average cache hit ratio and in average startup latency ratio.  相似文献   

7.
A modularized,network,reconfigurable architecture and design method of embedded control module is proposed.This control module uses a TMS320F2812 chip as the core,and introduces modularization,network,reconfigurable theory to the design of control module to better meet the flexible and reconfigurable control need of assembly line.The design method of the control module is verified by constructing a control experiment based on controlling of precision x-y displacement platform through a CAN bus.Experimental results show that the controlling repeat position accuracy of precision x-y platform by control module is 0.5μm and the position error is less than 1μm which meet the needs of micro-adjustment pose of assembly line.  相似文献   

8.
With the development of information technology, DSS can be used to resolve the complex process of the feasible reasoning and scientific decision-making of projects. This paper offers 7 exploiting principles for the computer support system on feasible reasoning and scientific decision-making of projects, that is, the principles of standardization, procedure, specification, agility, currency, practicability and development. On the basis of analysis on systematic procedure, the computer support system on feasible reasoning and scientific decisionmaking of projects is formed based on WEB, and its general structure, system function and the methods to be realized are introduced. The data composition of this system is analyzed following the principles of integrality,development, perspicuity and consistency. Also, the model-base management system is designed for the management of model storage and management of model operation.  相似文献   

9.
With the development of knowledge economy, the competition between high teehnology enterprises has gradually evolved into the competition of core competence based on knowledge, because high technology enterprises are typical knowledge-based enterprises. Few enterprises, especially for high technology firms, have all of the knowledge they need to compete effectively in the marketplace both at home and abroad, so more and more high technology companies are taking the advantage of strategic alliances to get their complementary knowledge. Since knowledge is the source of an enterprise' s competitiveness, knowledge management has become the most important means for enterprises to gain competitive advantage. There has been an increased growth in the literature on strategic alliances in recent decades. But what is less discussed in the existing literature on strategic alliances is the issue of knowledge management of strategic alliances in high technology enterprises. Based on the characteristics of strategic alliances in high technology enterprises, and in line with the implication and the goal of knowledge management, this study tries to delve into this issue. The paper analyzes the key factors relevant to the knowledge management of strategic alliances in high technology enterprises and proposes guidelines on the process and measures that should be taken in the knowledge management of strategic alliances in high technology enterprises.  相似文献   

10.
The Daya Bay Reactor Neutrino Experiment is to measure the smallest mixing angle θ13.The experiment contains three major experiment halls,Daya Bay near site,Linao near site and far site,and two major kinds of detectors,antineutrino detector which is to detect the antineutrinos by the inverse beta-decay reaction in Gd-LS,and muon detector which is to study and reject cosmogenic backgrounds.The goal of the detector control system(DCS)is to operate and detect the detectors and keep them running in safety.In consideration of the limited fund of this system and manpower of working on this system,the LabVIEW is chosen to develop the detector control system.The architecture of DCS adopts the distributed data management which is based on client-server model.The server part is to detect and operate parameters from hardware,save data to database and release data to clients,the client is to receive data from the server.The detector control system contains three parts:the hardware part,the local control system and the global control part.The local control system includes high voltage supply system,low voltage supply system,VME crate system,temperature and humidity system,gas pressure system,and so on.  相似文献   

11.
多媒体系统中影响流媒体的QoS有多种因素,将多媒体系统应用建立在RT-CORBA中间件实体上可以较好的保证流媒体QoS.本文采用扩展RT-CORBA的A/V流服务框架,在实时分布式多媒体应用中为流媒体提供QoS的管理功能,解决实时A/V流缓冲问题,并提供相应机制支持RT-CORBA环境下的流媒体QoS.实验结果表明基于RT-CORBA的实时多媒体系统较好地实现了分布式网络环境下的流媒体播放及刷新功能,保证了A/V流的QoS.将RT-CORBA规范应用于流媒体技术中能较好实现对流的管理和控制,从而保证实时流媒体传输质量.  相似文献   

12.
基于FMS2的在线视频录制系统设计与实现   总被引:1,自引:0,他引:1  
基于网络教学作业系统对多媒体表征的支持性不好,利用FMS2和流媒体技术设计实现了可在线录制视频的作业系统,详细探讨了系统架构、配置环境的设计,对实现在线录制视频作业要解决的关键技术进行了研究。  相似文献   

13.
概述了多媒体数据压缩编码技术和压缩标准,指出了多媒体数据压缩算法在流媒体技术中的重要性。  相似文献   

14.
基于双目立体视觉的医用三维电子内窥镜系统   总被引:1,自引:0,他引:1  
为了施行较为复杂的微创外科手术,设计了医用三维电子内窥镜系统,对系统的工作原理、显示方式等进行了分析。该系统基于双目立体视觉原理,采用双CCD摄像机模拟人眼实现了机器立体视觉;利用Zemax软件辅助设计了双光路内窥镜光学系统;通过比较几种立体显示方式的优缺点,选择了无源偏振眼镜立体显示方法,该方法采用基于FPGA的时分制立体显示技术,左右图像以100Hz帧频交替显示,并与液晶调制屏同步,观察者佩戴偏振眼镜即可观察到清晰无闪烁立体图像。经临床试验表明:简化了的光学系统的电子内窥镜图像质量得到显著提高;图像帧频达到100Hz,无闪烁感,且无停顿、拖尾、扭曲和停滞等现象。该系统可广泛应用于微创外科手术中,并可作为腹腔手术机器人的显示系统使用。  相似文献   

15.
随着互联网的普及,网络已经成为人们获取信息的重要渠道,各种各样的多媒体应用层出不穷,但网络带宽却影响着信息传输的速度,因此流媒体技术应运而生,并不断发展,进而得到广泛应用。本文在介绍流媒体技术基本概念的基础上,分析了流媒体技术的基本现状,并提出了相应的策略。  相似文献   

16.
网络地形漫游的数据传输与缓存方法   总被引:1,自引:1,他引:0  
为了解决网络地形漫游时的连续性问题,缓解网络数据拥塞时的数据供应压力,通过分析地形几何数据与流媒体数据在组织方式及漫游时数据预取方向的不同,结合基于GPU的绘制技术,设计了新的地形数据传输及缓存方法.该方法根据客户端处理能力及网络性能划分地块的粒度,由客户端生成多分辨率地形并缓存部分数据,降低绘制数据对网络性能的依赖.在运行时刻根据视点位置确定周围地块的传输规则,使各地块数据的传输量根据运动方向进行自适应调整,保证了漫游时绘制的连续性,大大提升了网络地形绘制的性能和效果.  相似文献   

17.
介绍了网格技术及流媒体技术。针对目前网络流媒体应用在网络带宽、服务器性能和节目来源等方面的局限性,给出相应的流技术解决方案。选择利用网格技术改善运行平台,并阐述了网格平台的体系结构及网格流媒体的发展趋势。  相似文献   

18.
随着计算机技术和网络通讯技术的发展以及计算机使用的普及,改变了人们的生活和学习方式。如何有效利用网络流媒体应用平台与以往固定场馆的结合来进行展览教育、科技培训、科技报告,成为了计算机应用领域重要的研究课题。交互式视频点播系统(VOD)具有多层次的分布式体系结构,采用了独有的计算机网络技术,支持多种教学终端和教学手段,是能够实现跨地域的复杂网络环境和大规模的并发学习访问的多媒体信息系统。  相似文献   

19.
流媒体服务的瓶颈是磁盘带宽,而不同用户请求的数据长相关,区间缓存策略可以减少磁盘I/O。用户的交互请求改变了服务器的状态,影响缓存算法。针对交互引入了惰性替换的优化,并用竞争分析从理论上讨论了帧分类存储模式对缓存算法的影响。在最坏情况下,分类存储模式和顺序存储模式下缓存算法的磁盘I/O竞争比是常数。  相似文献   

20.
超媒体又称媒体穿越,是超文本和多媒体在信息浏览环境下的结合,除了具有超文本的全部功能以外,还能够处理多媒体和流媒体信息。它是以多媒体方式呈现的相关文件信息,这种艺术与技术层面上的超媒体,在市场与服务的多元化的整体竞争中迅速演变与不断完善着,这一新兴的商业思维模式也不断地应用至现代企业连锁信息标准化管理之中。  相似文献   

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