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1.
Multi-channel and single-channel image denoising are on two important development fronts. Integrating multi-channel and single-channel image denoisers for further improvement is a valuable research direction. A natural assumption is that using more useful information is helpful to the output results. In this paper, a novel multi-channel and single-channel fusion paradigm (MSF) is proposed. The proposed MSF works by fusing the estimates of a multi-channel image denoiser and a single-channel image denoiser. The performance of recent multi-channel image denoising methods involved in the proposed MSF can be further improved at low additional time-consuming cost. Specifically, the validity principle of the proposed MSF is that the fused single-channel image denoiser can produce auxiliary estimate for the involved multi-channel image denoiser in a designed underdetermined transform domain. Based on the underdetermined transformation, we create a corresponding orthogonal transformation for fusion and better restore the multi-channel images. The quantitative and visual comparison results demonstrate that the proposed MSF can be effectively applied to several state-of-the-art multi-channel image denoising methods.  相似文献   
2.
Multi-channel IEEE WAVE 1609.4 protocol has been proposed to guarantee the co-existence of safety and non-safety applications over the same Vehicular Ad hoc NETwork (VANET) scenario. While the usage of multi-channel avoids the risk of collisions between applications allocated on different frequencies, its implementation on a single-radio transceiver poses some major concerns about the effective utilization of the channel resources. In this paper, we study the performance of safety applications over multi-channel single-radio VANETs, and we present three novel contributions in this regard. First, we propose an analytical analysis and a simulation study of IEEE 1609.4. We show the harmful impact of synchronous channel switching on the message delay and delivery ratio. Second, we investigate the problem of dissemination of safety broadcast messages over multi-channel VANETs, where the network is intermittently disconnected, due to the alternation of control and service intervals. Finally, we propose a WAVE-enhanced Safety message Delivery (WSD) scheme to enable fast dissemination of safety messages over multi-channel VANETs, while guaranteeing compatibility with the existing WAVE stack. To this aim, we formulate the dissemination problem as a multi-channel scheduling problem. We further introduce cooperation among vehicles to reduce the dissemination latency. Simulation study shows the ability of the WSD scheme to enhance the performance of IEEE 1609.4 in terms of message delay and delivery ratio under different topologies and various applications.  相似文献   
3.
Wireless infrastructure networks (WINs) provide ubiquitous connectivity to mobile nodes in metro areas. The nodes in such backbone networks are often equipped with multiple transceivers to allow for concurrent transmissions in multiple orthogonal channels. In this study, we develop an analytical model for the estimation of the delay and throughput performance of wireless infrastructure networks employing slotted ALOHA channel access and slotted Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) over multiple channels. The analytical model, which takes into account the correlation due to multi-hop transmissions, approximates the performance observed through simulations accurately.  相似文献   
4.
随着颜色复制精度的提高,含有浅色墨的多通道喷墨打印系统使用范围越来越广,但是含浅色墨的喷墨打印系统墨色维度高,光谱冗余严重,分色数据量较大、灵活性不高,且由于同色油墨间的相关性,映射精度对分色精度影响较大。针对这些问题,本研究在色域划分思想的基础上,基于分区纽介堡方程理论,结合灰成分替代原理以及两种色墨替代原理,建立了CMYKcmk两种色墨喷墨打印系统的分色计算模型。结果表明本方法能够减少分色计算量,提高分色可调整性,较好地实现两种色墨喷墨打印分色。  相似文献   
5.
配电智能终端是智能配电网的重要组成部分,是实现配电网自动化的关键。文章针对集中式智能终端在处理时间、资源需求方面的缺点和传统分布式智能终端相邻保护配合困难的问题,利用最新电子通信技术的发展成果,进行智能控制终端数据传输机制和自适应、自组织、自管理方案的研究,采用分布式智能控制方式,开发设计了多通道分布式智能配电网终端,从而实现了电网保护的快速性和选择性的统一。  相似文献   
6.
为了满足不同网络环境下的用户需求,视频节目往往需要经过多次编码以产生不同码率的多个码流.这种多次独立编码方式存在计算资源消耗大和效率低等问题,利用视频在不同码率编码时存在的编码信息相关性,设计了基于编码信息复用的多路x265视频编码系统,使多个从编码器复用主编码器产生的编码信息,如编码单元(CU)的层次划分信息、预测单元(PU)的模式判别信息以及运动估计参考帧信息等,从而大幅提高多路编码效率.该系统支持单路视频输入,进行基于信息复用的多路编码后,同时输出不同码流的多路码流.实验结果表明,与传统的多次独立x265编码相比,该系统在保证视频质量的前提下,对高清1080p和准高清720p视频分别节省了43.32%和52.79%的编码时间.  相似文献   
7.
Over the last few years, we have encountered an exponential growth in online communication opportunities. Organizations have more and more ways to connect and engage with their current or future customers. The existence of more opportunities in connecting to people can be both an enabler and a burden. Being present at a multitude of different channels requires the effective management of a very large number of adapted contents, formats, and interaction patterns fulfilling the communication and cooperation needs of distributed target groups. In this respect, we integrate existing fragmented communication and monitoring approaches into a full-fledged communication model as a basis for an adequate engagement approach. We describe applications of our approach in both the eTourism and manufacturing domain. In this paper, we introduce an approach that will enable communication, collaboration and value exchange of users through a multitude of online interaction possibilities based on the use of semantic technology. Finally, we also compare our approach with existing solutions with respect to the identified challenges in this subject.  相似文献   
8.
孙建涛  张平 《电子与信息学报》2010,32(10):2371-2376
散射波干扰极大地破坏了合成孔径雷达(Synthetic Aperture Radar,SAR)对地物目标的识别,利用快时间STAP(Space Fast-time Adaptive Processing)可以对散射波干扰进行有效抑制.该文针对多通道SAR, 讨论了互谱测度法在散射波干扰抑制中的应用,分析了干扰加噪声协方差矩阵的互谱,仿真讨论了互谱测度法求解的加权矢量对散射波干扰抑制性能的影响,并和基于主分量分析的散射波干扰抑制算法性能进行了比较.仿真结果表明在同样的自由度下,互谱测度法较主分量分析法可以取得较优的散射波干扰抑制性能.  相似文献   
9.
利用高温超导薄膜材料的低插损特性,实现了具有相位一致性的新型高温超导高性能三通道滤波器组,该器件置于接收机前端系统的低噪声放大器前可以使接收机前端系统同时具有带外抗干扰特性和带内低损耗特性,并具有极高的灵敏度。  相似文献   
10.
We study the problem of disseminating data of time-constrained services through multiple broadcast channels. By time-constrained services, we mean those services whose data must reach clients before a certain constrained time. Otherwise, the data would become useless or substantially less valuable to the clients. We first explore the difficulties of solving the problem and derive the theoretical minimum number of channels required for the task. Then, we propose a transformation-based data allocation (TDA) algorithm that guarantees to fulfill the task (i.e., all requested data reach the clients within the constrained time) by using the minimum number of channels. Finally, we analyze the computation complexity and prove the validity and optimality of the TDA algorithm.  相似文献   
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