A noise immunity controlled quantum teleportation protocol

Quantum Information Processing - With the advent of the Internet and information and communication technology, quantum teleportation has become an important field in information security and its...     

基于案例分析金字塔模型的主动运维案例体系建设

针对传统运维案例在经验共享和处置效率方面的不足及运维领域同类事件重复发生概率高、处置差异大的情况,提出一种案例分析金字塔模型,使用基于向量化解析和知识分层提取的素材库构建方法,实现由生产运维操作标准库、生产运行异常事件库到案例素材库再到案例教学库的自动生成转变,并以金字塔模型为基础,通过引入改进的趋势预测分析方法、案例推理"5R"模型和"4S"案例教学模式完善预警预测、辅助决策、案例教学相关应用,建立主动运维案例体系。实践结果表明,通过整个体系的推行,改变了企业信息系统运维被动应付的局面,同类事件占比逐年降低,事件响应时间和处置时间明显缩短,运维服务质量大幅提升。     

A secure and high-performance multi-controller architecture for software-defined networking

Controllers play a critical role in software-defined networking (SDN). However, existing single-controller SDN architectures are vulnerable to single-point failures, where a controller’s capacity can be saturated by flooded flow requests. In addition, due to the complicated interactions between applications and controllers, the flow setup latency is relatively large. To address the above security and performance issues of current SDN controllers, we propose distributed rule store (DRS), a new multi-controller architecture for SDNs. In DRS, the controller caches the flow rules calculated by applications, and distributes these rules to multiple controller instances. Each controller instance holds only a subset of all rules, and periodically checks the consistency of flow rules with each other. Requests from switches are distributed among multiple controllers, in order to mitigate controller capacity saturation attack. At the same time, when rules at one controller are maliciously modified, they can be detected and recovered in time. We implement DRS based on Floodlight and evaluate it with extensive emulation. The results show that DRS can effectively maintain a consistently distributed rule store, and at the same time can achieve a shorter flow setup time and a higher processing throughput, compared with ONOS and Floodlight.     

A virtual service placement approach based on improved quantum genetic algorithm

Despite the critical role that middleboxes play in introducing new network functionality, management and innovation of them are still severe challenges for network operators, since traditional middleboxes based on hardware lack service flexibility and scalability. Recently, though new networking technologies, such as network function virtualization (NFV) and software-defined networking (SDN), are considered as very promising drivers to design cost-efficient middlebox service architectures, how to guarantee transmission efficiency has drawn little attention under the condition of adding virtual service process for traffic. Therefore, we focus on the service deployment problem to reduce the transport delay in the network with a combination of NFV and SDN. First, a framework is designed for service placement decision, and an integer linear programming model is proposed to resolve the service placement and minimize the network transport delay. Then a heuristic solution is designed based on the improved quantum genetic algorithm. Experimental results show that our proposed method can calculate automatically the optimal placement schemes. Our scheme can achieve lower overall transport delay for a network compared with other schemes and reduce 30% of the average traffic transport delay compared with the random placement scheme.     

势能增氧生态净化工艺在高浓度有机废水处理中的应用

比较污水处理好氧工艺生物转盘法和滴滤池法的优缺点,并结合两种废水处理方法的优点,设计新的工艺——势能增氧生态净化工艺,对南京市腊梅食品厂高浓度有机废水进行处理。结果表明,势能增氧生态净化工艺设计简单,不需鼓风曝气,污水进入废水处理系统后出水即达到所要求的水质标准,且全部自控管理,具有废水处理效果佳、运行费用低的特点。     

基于网络环境下计算机文件信息安全的研究

计算机文件已经成为人们日常办公、学习的主要应用手段。如何加强计算机文件信息安全已经成为当前IT行业研究的趋势和热点。本文针对网络环境下计算机文件进行研究,首先描述了计算机文件信息安全的含义及意义;其次分析网络环境下影响计算机文件信息安全的因素;最后针对影响因素给出了相应的防范措施。     

VMPlanner: Optimizing virtual machine placement and traffic flow routing to reduce network power costs in cloud data centers

In recent years, the power costs of cloud data centers have become a practical concern and have attracted significant attention from both industry and academia. Most of the early works on data center energy efficiency have focused on the biggest power consumers (i.e., computer servers and cooling systems), yet without taking the networking part into consideration. However, recent studies have revealed that the network elements consume 10–20% of the total power in the data center, which poses a great challenge to effectively reducing network power cost without adversely affecting overall network performance. Based on the analysis on topology characteristics and traffic patterns of data centers, this paper presents a novel approach, called VMPlanner, for network power reduction in the virtualization-based data centers. The basic idea of VMPlanner is to optimize both virtual machine placement and traffic flow routing so as to turn off as many unneeded network elements as possible for power saving. We formulate the optimization problem, analyze its hardness, and solve it by designing VMPlanner as a stepwise optimization approach with three approximation algorithms. VMPlanner is implemented and evaluated in a simulated environment with traffic traces collected from a data center test-bed, and the experiment results illustrate the efficacy and efficiency of this approach.     

水轮机过流部件空蚀分析及预防

在检查、分析宝珠寺水电站水轮机过流部件数年来的空蚀情况的基础上,探索出了一些处理和预防在水质较清洁河流中运行的水轮机空蚀的有效方法,使其水轮机的运行状况得到持续的改善.这些方法可供同类型水电站水轮机空蚀的处理和预防借鉴.     

地震待载作用下地下韵筋混凝土结构 报伤破杯模拟研究

综合运用钢筋混凝土和土体两种材料非线性本构模型,对某工程实例进行地震破坏的模拟研 究。分析结果表明,结构内部在强震作用下产生了混凝土开裂、钢筋屈服等损伤和破坏,通过与采用 弹性结构模型的计算结果进行对比,发现采用弹性结构模型虽然可以得到与非线性模型相近的结构位 移,但是会显著低估结构内发生的变形,并且无法准确指示结构内部发生损伤的部位。因此,采用非 线性结构模型分析地下结构的抗震安全性是非常必要的。