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多层网络中的联合资源配置方案   总被引:3,自引:3,他引:0       下载免费PDF全文
在多层网络的资源配置中,为了实现备份资源在各网络层的最大共享,在综合考虑网络各层的资源使用信息和拓扑信息的基础上,提出了一种联合的资源配置方案.在建立资源分配方案的整数线性规划模型的同时,提出了适合解决大规模网络的遗传算法.数值结果表明:联合资源配置方案可以更好地共享各网络层的备份资源,从而使多层网络具有更高的带宽利用率和更低的运营成本.由于引入了各网络层的协调,从而防止了回路问题.  相似文献
2.
Performance improvement for optical packet switch with shared buffers   总被引:2,自引:0,他引:2  
In this paper, an inner wavelength method is proposed to enlarge buffering capacity of shared fiber delay line buffers. In addition, an optical packet switch called extended shared buffer type optical packet switch (extended SB-OPS) is proposed to realize the inner wavelength method. In order to further improve performance of extended SB-OPS, a greedy algorithm based on inner wavelength method is introduced. The performance of extended SB-OPS is evaluated by simulation experiments.  相似文献
3.
In this paper, a novel concept of multi-granularity p-cycle is proposed. In conventional p-cycle concept, all on-cycle spans have the same capacity. However, in multi-granularity p-cycle, each on-cycle span could have different capacity. Resnlts show that multi-granularity p-cycles are much more capacity-efficient and cost-effective than conventional p-cycles. We also propose two protection switching schemes for all types of p-cycle networks. One is wrapping protection, in which only two end nodes do real-time switching when a span failure happens. The other is steering protection, in which at most four nodes do real-time switching when a span fails. In steering protection switching scheme, the restoration path for the failure traffic demand has the least hops.  相似文献
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水声数字遥控系统   总被引:2,自引:0,他引:2       下载免费PDF全文
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不确定性边缘表示与提取的认知物理学方法   总被引:1,自引:0,他引:1       下载免费PDF全文
吴涛  金义富  侯睿  杨俊杰 《物理学报》2013,62(6):64201-064201
图像边缘检测是图像处理的一种重要技术, 其中不确定性表示与提取是关键问题之一. 在现有模拟物理学思想的相关方法基础之上, 提出了基于认知物理学的不确定性边缘表示与提取方法. 该方法利用数据场发现图像全局灰度认知, 构建图像灰度值空间到数据场势值空间的映射关系, 从场论的角度建立了可扩展的理论框架、统一了现有相关方法; 另一方面, 构造半升云模型建立云模型确定度的变化幅度与边缘像素表示与提取的内在关联关系, 最终在认知物理学核心理论的支持下实现图像不确定性边缘表示与提取. 所提出的方法时间耗费近似与图像尺寸成线性关系. 定性和定量的实验结果及分析表明, 该方法的分割效果较好, 性能稳定, 具有合理性和有效性. 关键词: 边缘检测 图像分割 云模型 数据场  相似文献
6.
This paper investigates the problem of dynamic protected lightpath services provisioning in optical mesh networks employing wavelength division multiplexing (WDM). A variety of schemes for dynamic protected services provisioning have been proposed, supporting a range of tradeoffs among restoration speed, capacity efficiency, and scalability. In this paper, we propose a novel scheme, called p-cycles-based maximum protected working capacity envelope (PC-MPWCE), which can offer an attractive combination of features: ring-like speed, mesh-like capacity efficiency, and good scalability. To evaluate the performance of PC-MPWCE, we compare it via simulation with 1 + 1 automatic protection switching (APS) and two well-known shared backup path protection (SBPP) on NSFNET. Our simulation results show that PC-MPWCE can achieve much better blocking performance than 1 + 1 APS, and perform the similar blocking performance and capacity efficiency as SBPP.  相似文献
7.
In this paper,a novel concept of multi-granularity p-cycle is proposed.In conventional p-cycle concept,all on-cycle spans have the same capacity.However,in multi-granularity p-cycle,each on-cycle span could have different capacity.Results show that multi-granularity p-cycles are much more capacity-efficient and cost-effective than conventional p-cycles.We also propose two protection switching schemes for all types of p-cycle networks. One is wrapping protection, in which only two end nodes do real-time switching when a span failure happens.The other is steering protection,in which at most four nodes do real-time switching when a span fails.In steering protection switching scheme,the restoration path for the failure traffic demand has the least hops.  相似文献
8.
本文给出了一种完整的供水声通信、数传、遥测、遥控以及水声传播研究用的水声发射系统,包括可编程信号源,高效功率放大器和宽带高效发射换能器等部分,具有良好的功能和实用价值。  相似文献
9.
测试了Er/Yb:KY(WO4)2晶体在室温下3个轴Ng,Np,Nm方向上的吸收光谱,分析比较光谱特性,并计算出各能级跃迁的吸收截面,其中沿Np轴方向有最强的吸收和较大的吸收截面,这有利于激光上能级的粒子数堆积,增大跃迁几率,加强荧光输出.由于掺入Yb3+离子,晶体在980 nm附近有很强的吸收和较大的半峰宽.该晶体在980 nm激光泵浦下有上转换绿光和红光,3个晶轴NP,Ng,Nm轴方向的上转换荧光,波峰位置相差甚微,强弱区别明显,且呈现的各向异性,其中Np方向最强.  相似文献
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