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951.
Dingde Jiang Lei Shi Peng Zhang Xiongzi Ge 《Multimedia Tools and Applications》2016,75(22):14307-14328
For many applications of multimedia medical devices in clinical and medical issues, cloud computing becomes a very useful way. However, high energy consumption of cloud computing networks for these applications brings forth a large challenge. This paper studies the energy-efficient problem with QoS constraints in large-scale cloud computing networks. We use the sleeping and rate scaling mechanism to propose a link energy consumption model to characterize the network energy consumption. If there is no traffic on a link, we will let it be sleeping. Otherwise, it is activated and we divide its energy consumption into base energy consumption and traffic energy consumption. The former describes the constant energy consumption that exists when the link runs, while the later, which is a quadratic function with respect to the traffic, indicates the relations between link energy consumption and the traffic on the link. Then considering the relation among network energy consumption, number of active links, and QoS constraints, we build the multi-constrained energy efficient model to overcome the high energy consumption in large-scale cloud computing networks. Finally, we exploit the NSF and GEANT network topology to validate our model. Simulation results show that our approach can significantly improve energy efficiency of cloud computing networks. 相似文献
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953.
The original measurement device-independent quantum key distribution is reviewed, and a modified protocol using heralded pair coherent state (HPCS) is proposed to overcome the quantum bit error rate associated with the dark count rate of the detectors in long-distance quantum key distribution. Our simulation indicates that the secure transmission distance can be improved evidently with HPCS owing to the lower probability of vacuum events when compared with weak coherent source scenario, while the secure key rate can be increased with HPCS due to the higher probability of single-photon events when compared with heralded single-photon source scenario. Furthermore, we apply the finite key analysis to the decoy state MDI-QKD with HPCS and obtain a practical key rate. 相似文献
954.
Cheng-Hua?Bai Dong-Yang?Wang Shi?Hu Wen-Xue?Cui Xin-Xin?Jiang Hong-Fu?WangEmail author 《Quantum Information Processing》2016,15(4):1485-1498
We propose a deterministic scheme to implement the multiqubit controlled-NOT gate of photons and multiqubit controlled-phase gate of electron spins with one control qubit and multiple target qubits using quantum dots in double-sided optical cavities. The scheme is based on spin selective photon reflection from the cavity and can be achieved in a nondestructive way. We assess the feasibility of the scheme and show that the gates can be implemented with high average fidelities by choosing the realistic system parameters appropriately. The scheme is useful in quantum information processing such as entanglement preparation, quantum error correction, and quantum algorithms. 相似文献
955.
Yu-Guang?YangEmail author Zhi-Chao?Liu Xiu-Bo?Chen Wei-Feng?Cao Yi-Hua?Zhou Wei-Min?Shi 《Quantum Information Processing》2016,15(9):3833-3840
Existing classical post-processing (CPP) schemes for quantum key distribution (QKD)-based quantum private queries (QPQs) including the \(kN\rightarrow N\), \(N\rightarrow N\), and \(rM\rightarrow N\) ones have been found imperfect in terms of communication efficiency and security. In this paper, we propose a novel CPP scheme for QKD-based QPQs. The proposed CPP scheme reduces the communication complexity and improves the security of QKD-based QPQ protocols largely. Furthermore, the proposed CPP scheme can provide a multi-bit query efficiently. 相似文献
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957.
为了满足航电系统中前端传感器捕获的图形图像数据实时传输的需求,设计并实现了基于PCIe总线的双路1394B接口模块。该模块通过PCIe接口与主机交互,采用S400β传输模式,软件设计符合标准OHCI规范,支持AS5643协议,异步流包数据收发采用链式队列管理,主机与1394B控制器之间通过DMA操作,实现大数据块的并行处理,两路1394B相互独立,显著提升数据传输性能。测试验证结果表明,该模块具备带宽高、可靠性高、CPU资源占用率低等特点,已在某项目获得成功应用,实现了图形图像数据的实时传输,满足系统设计要求,表现出了良好的稳定性和适应性,具有实践应用价值。 相似文献
958.
基于特征映射的微博用户标签兴趣聚类方法 总被引:1,自引:1,他引:0
针对现有的用户兴趣聚类方法没有考虑用户标签之间存在的语义相关性问题,提出了一种基于特征映射的微博用户标签兴趣聚类方法。首先,获取待分析用户及其所关注用户的用户标签,选取出现频数高于设定阈值的标签构建模糊矩阵的特征维;然后,考虑标签之间的语义相关性,利用特征映射的思想将用户标签根
据其与特征维标签之间的语义相似度映射到每个特征维下,计算每个特征维所对应的特征值;最后,利用模糊聚类得到了不同阈值下的用户兴趣聚类结果。实验结果表明,本文提出的基于特征映射的微博用户标签兴趣聚类方法有效地改善了用户兴趣聚类效果。 相似文献
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