光网络中关键性光子集成器件的研究进展

从高速率大容量光纤网络体系基本功能构架(即信息的超大容量传输、灵活的上下载路分插复用、快速的交换共享和高效经济的路由选择)的需求出发, 指出光子集成是实现上述功能构架的关键硬件, 包括高速响应的集成激光源、波导光栅阵列密集波分复用器、窄带响应集成光电探测器、路由选择的波长变换器、快速响应光开关矩阵以及低损耗多址波导分束器等, 并对发展趋向作出评论.     

区域性UDDI的节点间数据同步技术研究

目前区域性UDDI大多为单节点,有些虽为多节点但节点之间不是采用数据同步而是使用统一的数据库。这导致整个系统的安全性不高、扩展性不好和效率低下等问题。因此本文采用P2P技术和报文技术实现了区域性UDDI系统中各节点的数据同步,很好地解决了以上问题,实现了“一次注册,到处发布”的功能,提高了系统的安全性、可扩展性和效率。     

快速Hermite径向基函数曲面重构

在这篇论文中,我们提出了一个使用局部支撑径向基函数对三维散乱点进行Hermite插值或逼近的快速曲面重构方法.通过构造给定数据点集的一个层次结构,采用逐层精化的方式实现了全局曲面重构的效果,解决了因使用局部支撑径向基函数导致的问题.另外,设计一个基于逼近误差导向的径向基函数中心点选择策略,减少每层进行插值的数据点,从而使Hermite径向基函数曲面重构方法能处理百万以上规模的点云数据.实验结果显示,我们的方法还适用于极度非均匀分布或带噪声的点云数据的曲面重构.     

无需随机预言机的自适应攻陷模型下选择密文安全的单向代理重加密方案

如何构建一个在自适应攻陷模型下满足选择密文安全的单向代理重加密方案,目前尚属有待解决的重要问题.针对这一现状,文中提出了一个新的单向代理重加密方案,并在不依赖随机预言机模型的前提下,证明了方案在自适应攻陷模型下的选择密文安全性.与目前存在的不依赖随机预言机模型的Libert-Vergnaud单向代理重加密方案相比,该方案除了具有更强的安全性之外,在效率方面也具有较明显的优势.     

基于安全性价值的含大风电的电力系统扩展规划

以大规模风电中接入为背景,建立了计系统态和动态安全性价值电源、电网统一规模型.在安全性价值评估中,以日前组组合为工具,以预测规水平年时序负荷和风电出力数据为础,通过全年逐时段仿真,评估对可能发生预事故进行预防控制和紧控制带来发电燃料成本、环成本以切、切负荷成本,同时计入负荷和风电出力不确定性引起控制措施无效时社会损失,从而为规方案安全性评估提供了一个系统方法,也将电力系统规视角从传统技术经济评估拓宽为社会价值评估.预防控制与紧控制中对连事故考虑为规方案安全性评估中嵌入连事故影提供了有力工具,也使系统安全性评估更为全面、合理.通过于新英格兰1039节点系统图两个规方案评估验证了本文提模型与方法,并表明了在规中计安全性价值和对规水平年时序逐小时地模拟系统运行重要影.     

冲击荷载作用下CRTSⅢ型板式轨道-路基系统动力特性研究

应用ABAQUS有限元软件建立CRTSⅢ型板式轨道-路基动力分析模型,计算了在落轴冲击荷载作用下CRTSⅢ型板式轨道-路基系统的动力响应,并将仿真计算结果与试验结果进行了对比,验证了模型的可靠性.在此基础上,研究了扣件刚度、路基基床弹性模量、自密实混凝土弹性模量以及长期服役状态下混凝土弹性模量的降低对轨道-路基系统动力特性的影响规律.结果表明:扣件刚度对各部件振动加速度影响较大,路基基床弹性模量对其影响较小;轨道结构在服役过程中混凝土弹性模量的降低会引起轨道板加速度有较大的增幅,应引起重视.     

层状单轴各向异性介质并矢Green函数的递推算法及精确计算

采用递推算法计算任意数目三维层状单轴各向异性介质的并矢Green函数．根据层界面处电场和磁场的连续性条件得到3个确定Sommerfeld积分待定系数的线性方程组，分别对应于垂向单位电偶极子产生的TM波、水平方向单位电偶极子产生的TE波和TM波，这些方程组均可通过递推算法求解．只需改变3个线性方程组中源项元素的位置，就可以方便地得到当源点和场点在任意层时的并矢Green函数．通过将积分路径在复平面变形，有效地解决了出现在Sommerfeld积分中的奇异点问题．所给出的并矢Green函数表达式形式简洁、易于编程，且计算时无溢出现象．理论分析和数值计算举例说明了该算法的准确性和有效性．     

碳基储氢材料的研究进展

氢能是二十一世纪解决化石能源危机和缓解环境污染问题的绿色能源.实现氢能的利用,氢的储运是目前要解决的关键问题.储氢材料研究较多,碳基储氢材料是储氢材料中的一个重要分支.本文综述了碳纳米管、碳纤维、石墨、活性炭以及C<,60>等碳基材料的储氢性能及研究进展,讨论了各种碳基储氢材料目前存在的问题,并对其进一步研究进行了展望.     

基于形式化测试的实时系统变更后安全性验证

变更后系统实现的安全性验证是安全攸关系统维护过程中必不可少的环节,也是其面临的主要挑战之一.软件模型检测和程序验证是目前常用的作用于代码层面的自动化安全性验证技术.本文站在系统行为角度,基于形式化方法,提出了一种将变更后系统实现的安全性验证问题归结为一致性测试的方法,尝试通过自动生成的一致性测试用例在系统行为级别上判定系统实现是否安全.为此,首先以时间输入输出自动机及其语义模型为基础,构建了该方法的证明体系,证明了该方法的正确性;其次,建立了变更后系统实现安全性验证的回归测试生成框架.相对于其它实时系统测试方法,这种测试方法不仅可以发现实时系统中常规的不一致性缺陷,而且为变更后系统实现在运行时是否满足指定的安全性属性提供了依据.最后,以轨道交通系统中的列车自动防护功能的变更情景为案例研究,说明了方法的具体应用.     

环境污染应急系统中决策方案设计研究

环境污染已严重威胁着人民生命和财产的安全,制约了国家经济可持续发展能力.鉴于此问题,给出了环境污染应急系统的组织机构及其主要职责;详细分析了环境污染应急处理系统信息流向及其各环节中的信息处理事务;给出了环境污染的各种类型方式;探讨了应急系统中专家成员库、物资资源库、地理信息库、污染类型库及其它相关数据库的设计规范,解决了应急决策中数据支持问题;研究了影响制订工程抢险、人员调度、物资调度、污染治理、伤亡救助、交通线路选择、治安保卫等决策方案的各种因素,为形成正确的决策方案提供了理论上的支持,进一步地为应急系统提供了技术保障.     

实用化光纤量子加密电话网络和高速数据传输系统——现场应用与安全管理

本文以如何应用量子通信技术满足现场应用和安全管理需求为出发点,以国内最近完成的一个在现场光纤网络上搭建的多节点量子加密电话网络和高速数据传输系统为实例,具体分析了为满足现场应用和安全管理的需求,实用化光纤量子通信系统所采用设计方案,并简单介绍了该系统实施和长期运行情况.该系统满足了重要事务对于不同应用形式及高安全等级通信的需求,并验证了实际应用环境下的可靠性和易用性,具有很好的代表性.本文也对量子通信系统应用于公共管理提出了建议.     

精密测量中的量子极限

给定一个物理装置,对于一个物理可观察量能够得到的测量精度是什么?为了回答这一问题,本文以最近量子精密测量的发展为主线,量子参数估值方法为核心,介绍单粒子(线性耦合)体系和多粒子(非线性耦合)体系物理量测量精度的量子限制.作为例子,对光学量子精密测量中如何突破标准量子极限,甚至海森堡极限做了简明阐述.特别总结了非线性精密测量在突破海森堡极限方面的最新进展.最后,探讨了量子精密测量未来发展的可能趋势.     

基于经典Goppa码的非对称量子稳定子码构造

自从Calderbank等人建立了从经典纠错码构造量子纠错码的CRSS构造法以来,人们利用经典纠错码构造了大量的性能良好的量子纠错码,称为量子稳定子码．最近的物理实验表明,大多数量子力学系统中发生量子比特翻转错误的概率远小于量子相位翻转错误的概率,针对这一情况所构造的纠错码称为非对称量子纠错码．本文分别基于嵌套包含Goppa码与对偶包含Goppa码构造了一系列新的非对称量子稳定子码．在基于嵌套包含Goppa码构造非对称量子码时,首先对Goppa码的选取做一定的限制．以便解析构造量子码．对于一般情况下的构造,则是借助于数学软件Matlab计算Goppa码对偶码的最小距离进行的．在基于对偶包含Goppa码的构造中,所构造量子码的纠错能力主要体现在纠正Z类型错误上．     

Quantum jumps,superpositions, and the continuous evolution of quantum states

The apparent dichotomy between quantum jumps on the one hand, and continuous time evolution according to wave equations on the other hand, provided a challenge to Bohr's proposal of quantum jumps in atoms. Furthermore, Schrödinger's time-dependent equation also seemed to require a modification of the explanation for the origin of line spectra due to the apparent possibility of superpositions of energy eigenstates for different energy levels. Indeed, Schrödinger himself proposed a quantum beat mechanism for the generation of discrete line spectra from superpositions of eigenstates with different energies.However, these issues between old quantum theory and Schrödinger's wave mechanics were correctly resolved only after the development and full implementation of photon quantization. The second quantized scattering matrix formalism reconciles quantum jumps with continuous time evolution through the identification of quantum jumps with transitions between different sectors of Fock space. The continuous evolution of quantum states is then recognized as a sum over continually evolving jump amplitudes between different sectors in Fock space.In today's terminology, this suggests that linear combinations of scattering matrix elements are epistemic sums over ontic states. Insights from the resolution of the dichotomy between quantum jumps and continuous time evolution therefore hold important lessons for modern research both on interpretations of quantum mechanics and on the foundations of quantum computing. They demonstrate that discussions of interpretations of quantum theory necessarily need to take into account field quantization. They also demonstrate the limitations of the role of wave equations in quantum theory, and caution us that superpositions of quantum states for the formation of qubits may be more limited than usually expected.     

The best of many worlds,or, is quantum decoherence the manifestation of a disposition?

In this paper I investigate whether the phenomenon of quantum decoherence, the vanishing of interference and detectable entanglement on quantum systems in virtue of interactions with the environment, can be understood as the manifestation of a disposition. I will highlight the advantages of this approach as a realist interpretation of the quantum formalism, and demonstrate how such an approach can benefit from advances in the metaphysics of dispositions. I will also confront some commonalities with and differences to the many worlds interpretation, and address the difficulties induced by quantum non-locality. I conclude that there are ways to deal with these issues and that the proposal hence is an avenue worth pursuing.     

An axiomatic formulation of the Montevideo interpretation of quantum mechanics

We make a first attempt to axiomatically formulate the Montevideo interpretation of quantum mechanics. In this interpretation environmental decoherence is supplemented with loss of coherence due to the use of realistic clocks to measure time to solve the measurement problem. The resulting formulation is framed entirely in terms of quantum objects. Unlike in ordinary quantum mechanics, classical time only plays the role of an unobservable parameter. The formulation eliminates any privileged role of the measurement process giving an objective definition of when an event occurs in a system.     

Three principles for canonical quantum gravity

We outline three principles that should guide us in the construction of a theory of canonical quantum gravity: (1) diffeomorphism invariance, (2) implementing the proper dynamics and related constraint algebra, (3) local Lorentz invariance. We illustrate each of them with its role in model calculations in loop quantum gravity.     

Causality and chance in relativistic quantum field theories

Bell appealed to the theory of relativity in formulating his principle of local causality. But he maintained that quantum field theories do not conform to that principle, even when their field equations are relativistically covariant and their observable algebras satisfy a relativistically motivated microcausality condition. A pragmatist view of quantum theory and an interventionist approach to causation prompt the reevaluation of local causality and microcausality. Local causality cannot be understood as a reasonable requirement on relativistic quantum field theories: it is unmotivated even if applicable to them. But microcausality emerges as a sufficient condition for the consistent application of a relativistic quantum field theory.     

Interpretation neutrality in the classical domain of quantum theory

I show explicitly how concerns about wave function collapse and ontology can be decoupled from the bulk of technical analysis necessary to recover localized, approximately Newtonian trajectories from quantum theory. In doing so, I demonstrate that the account of classical behavior provided by decoherence theory can be straightforwardly tailored to give accounts of classical behavior on multiple interpretations of quantum theory, including the Everett, de Broglie–Bohm and GRW interpretations. I further show that this interpretation-neutral, decoherence-based account conforms to a general view of inter-theoretic reduction in physics that I have elaborated elsewhere, which differs from the oversimplified picture that treats reduction as a matter of simply taking limits. This interpretation-neutral account rests on a general three-pronged strategy for reduction between quantum and classical theories that combines decoherence, an appropriate form of Ehrenfest׳s Theorem, and a decoherence-compatible mechanism for collapse. It also incorporates a novel argument as to why branch-relative trajectories should be approximately Newtonian, which is based on a little-discussed extension of Ehrenfest׳s Theorem to open systems, rather than on the more commonly cited but less germane closed-systems version. In the Conclusion, I briefly suggest how the strategy for quantum-classical reduction described here might be extended to reduction between other classical and quantum theories, including classical and quantum field theory and classical and quantum gravity.     

混合量子遗传算法在软硬件协同综合中的应用研究

针对多处理器嵌入式系统,结合拟 Newton算法,提出了混合量子遗传算法(MQGA)在系统设计中的解决方案,并引入了模拟退火技术.实验结果表明,MQGA能有效解决软硬件划分问题,提高了求解质量和算法的收敛速度,降低了计算代价,保证了算法的自适应性和全局最优性