中国联通接入网浅析

1 接入网概述 接入网(AN)是泛指用户网络接口(UNI)与业务节点接口(SNI)间实现传送承载功能的实体网络。其目标是建立一种标准化的接口方式,以一个可监控的接入网络,使用户能够获得话音、租用线业务、数据多媒体、有线电视等综合业务。     

Finite-Key Analysis for a Practical High-Dimensional Quantum Key Distribution System Based on Time-Phase States

High-dimensional quantum states key distribution(HD-QKD) can enable more than one bit per photon and tolerate more noise. Recently, a practical HD-QKD system based on time-phase states has provided a secret key at Mbps over metropolitan distances. For the purposes of further improving the secret key rate of a practical HD-QKD system, we make two main contributions in this work. Firstly, we present an improved parameter estimation for this system in the finite-key scenario based on the Chernoff bound and the improved Chernoff bound. Secondly, we analyze how the dimension d affects the performance of the practical HD-QKD system.We present numerical simulations about the secret key rate of the practical HD-QKD system based on different parameter estimation methods. It is found that using the improved Chernoff bound can improve the secret key rate and maximum channel loss of the practical HD-QKD system. In addition, a mixture of the 4-level and 8-level practical HD-QKD system can provide better performance in terms of the key generation rate over metropolitan distances.     

Round-robin differential quadrature phase-shift quantum key distribution

Recently,a round-robin differential phase-shift(RRDPS) protocol was proposed[Nature 509,475(2014)],in which the amount of leakage is bounded without monitoring the signal disturbance.Introducing states of the phase-encoded Bennett-Brassard 1984 protocol(PE-BB84) to the RRDPS,this paper presents another quantum key distribution protocol called round-robin differential quadrature phase-shift(RRDQPS) quantum key distribution.Regarding a train of many pulses as a single packet,the sender modulates the phase of each pulse by one of {0,π/2,π,3π/2},then the receiver measures each packet with a Mach-Zehnder interferometer having a phase basis of 0 or π/2.The RRDQPS protocol can be implemented with essential similar hardware to the PE-BB84,so it has great compatibility with the current quantum system.Here we analyze the security of the RRDQPS protocol against the intercept-resend attack and the beam-splitting attack.Results show that the proposed protocol inherits the advantages arising from the simplicity of the RRDPS protocol and is more robust against these attacks than the original protocol.     

半绝对偏差投资组合模型构建及其应用

通过对模糊隶属函数以及基金投资组合基本模型的适当变形,构建了带交易费及流动性约束的极大极小-半绝对偏差投资组合模型.选取5支证券,依据2008年全年的数据作为样本数据,按投资者的不同偏好得出不同的最优投资策略,并对几种情形进行了对比,结果显示此模型能很好地反映出投资者的主观意愿,具有很好的灵活性.     

浅谈两台IC分选机并行测试方法

随着半导体行业测试技术不断提高,IC分选机技术不断升级,昂贵的集成电路测试设备是导致集成电路测试成本偏高的主要因素。如何最有效地使用好现有设备,充分利用设备资源,降低测试成本,提高测试效率,是工程技术人员需要探索的问题。从如何实现两台IC分选机并行测试展开具体的说明,详细介绍两台IC分选机与测试系统并行测试的通信原理,以及实际工作中的一些注意事项,避免出现质量事故,并通过试验说明并行测试的优越性。     

嵌入式组件技术的研究及应用

嵌入式系统不断增大的复杂度和市场实效性的要求推动了基于组件的开发技术(Componet-based Development,CBD)向嵌入式软件领域的转移.通过深入分析通用组件的设计原则和嵌入式系统的特性要求,提出了符合嵌入式系统的组件设计原则,并且根据嵌入式组件的特点.提出了一种基于"组件树"的嵌入式软件开发方法,使组件技术的优点在嵌入式系统中得到了很好的体现,为CBD技术向嵌入式领域的转移提供了一种有效的途径.     

Quantum hacking of two-way continuous-variable quantum key distribution using Trojan-horse attack

We present a Trojan-horse attack on the practical two-way continuous-variable quantum key distribution system. Our attack mainly focuses on the imperfection of the practical system that the modulator has a redundancy of modulation pulsewidth, which leaves a loophole for the eavesdropper inserting a Trojan-horse pulse. Utilizing the unique characteristics of two-way continuous-variable quantum key distribution that Alice only takes modulation operation on the received mode without any measurement, this attack allows the eavesdropper to render all of the final keys shared between the legitimate parties insecure without being detected. After analyzing the feasibility of the attack, the corresponding countermeasures are put forward.     

具有高概率的整数分解量子算法

本文基于量子Fourier变换给出了一个新的整数分解量子算法,通过利用多次量子Fourier变换和变量代换,使得r变成相位因子(r是从模N整数环中所选元素的阶),进而可使非零的非目标态的几率幅变为零,算法成功的概率大于3/4,高于Shor整数分解量子算法,且不再依赖于,的大小(Shor算法成功的概率依赖于r的大小),同...     

基于密集编码的多方与多方量子秘密共享

该文针对多方与多方之间的秘密共享问题,通过对Bell态的两个粒子分别进行相位旋转局域操作,以及Pauli变换与Hadamard变换、I变换之一复合的局域操作,基于密集编码思想提出一种新的多方与多方量子秘密共享协议。该协议不仅可以抵抗现有的攻击策略如密集编码攻击、纠缠交换攻击等,还可以抵抗代理成员的欺骗攻击,即具备可验证功能。同时,该协议还具有高效率、可动态更新子秘密和增减代理成员等特点。