面向多路径传输中数据隐私性分析的安全模型

In order to investigate the enhancement of data privacy by distributing data packets via multiple paths, this paper formulates a security model and analyzes the privacy problem in multipath scenarios leveraging information theoretic concept. Based on proposed model, a privacy function related to the path number is discussed. We heuristically recommend the optimal path number and analyze the tradeoff among the performance, resource consumption and privacy. For reducing the information leakage, the data schedule algorithms are also proposed. The analytical model can provide guidelines for the multipath protocol design.     

一种混合范数整形分辨率可调的波束形成器

针对实际应用中需要调节分辨率的现象,提出一种混合范数整形分辨率可调的波束形成器。该方法利用信号的稀疏特性与子空间方法使零陷和旁瓣降低的同时,根据l₂范数具有促进稠密解的特性,加入了对主瓣的l₂范数约束,从而增大主瓣的阵列增益强度,使主瓣宽度变窄。仿真结果表明,调节加权系数可以调节波束图的主瓣宽度、旁瓣高度和零陷深度,实现了分辨率可调的目的。也可以根据实际需要通过调节加权系数实现各性能参数间良好折衷。     

Analytical IMC-PID design in terms of performance/robustness tradeoff for integrating processes: From 2-Dof to 1-Dof

This communication addresses the analytical PID tuning rules for integrating processes. First, this paper provides an analytical tuning method of two-degree-of-freedom (2-Dof) PID controller using an enhanced internal model control (IMC) principle. On the basis of the robustness analyses, the presented method can easily achieve the performance/robustness tradeoff by specifying a desired robustness degree. Second, an analytical tuning method of one-degree-of-freedom (1-Dof) PID also is proposed in terms of performance/robustness and servo/regulator tradeoffs, which are not commonly considered for 1-Dof controller design. The servo/regulator tradeoff is formulated as a constrained optimization problem to provide output responses as similar as possible to those produced by the 2-Dof PID controller. The presented PID settings are applicable for a wide range of integrating processes. Simulation studies show the effectiveness and merits of the proposed method.     

多变量权衡覆盖网络拓扑建模

针对建立覆盖网络时资源和定位开销较大的问题, 以一种多目标权衡的方式, 使新节点加入网络时在多个因素之间进行权衡：与候选节点之间的距离代价以及从候选节点查询成功的代价, 建立非结构化覆盖网络拓扑模型。理论分析表明, 通过调节多个因素之间的比例, 即调节α、β的值可以获得不同类型的拓扑结构, 引导网络朝着预期的方向发展。仿真分析表明, 建立的覆盖网络不仅表现出较短的平均最短路径长度、节点平均度以及较大的簇系数, 具有小世界特性, 且节点度分布与真实网络模型相一致。     

Rate-adaptive weighted fair queueing for energy-aware scheduling

In this paper we study energy-aware scheduling that trades energy consumption against a traditional performance measure of delay. We use the power-rate function f(x)=c+x^α$f(x)=c+x^{\alpha }$ for x>0$x>0$ and f(0)=0$f(0)=0$ to model the power consumption, where c>0$c>0$ represents the base power. We give a definition of a rate-adaptive version of the Weighted Fair Queueing scheduling algorithm, and prove its energy consumption is within a bounded factor of the best possible when the algorithm guarantees the classic end-to-end delay for every connection.     

A bi-population based scheme for an explicit exploration/exploitation trade-off in dynamic environments

Optimisation in changing environments is a challenging research topic since many real-world problems are inherently dynamic. Inspired by the natural evolution process, evolutionary algorithms (EAs) are among the most successful and promising approaches that have addressed dynamic optimisation problems. However, managing the exploration/exploitation trade-off in EAs is still a prevalent issue, and this is due to the difficulties associated with the control and measurement of such a behaviour. The proposal of this paper is to achieve a balance between exploration and exploitation in an explicit manner. The idea is to use two equally sized populations: the first one performs exploration while the second one is responsible for exploitation. These tasks are alternated from one generation to the next one in a regular pattern, so as to obtain a balanced search engine. Besides, we reinforce the ability of our algorithm to quickly adapt after cnhanges by means of a memory of past solutions. Such a combination aims to restrain the premature convergence, to broaden the search area, and to speed up the optimisation. We show through computational experiments, and based on a series of dynamic problems and many performance measures, that our approach improves the performance of EAs and outperforms competing algorithms.     

光学相关识别在飞行器精确定点着陆中的应用

提出将光学相关识别应用于着陆点的选择中,以解决飞行器精确定点着陆问题.用"嫦娥一号"探测卫星传回的第一幅月球表面照片建立着陆点模型,通过尺度缩放模拟着陆过程中目标的尺度变化.利用优化折中综合鉴别函数(OTSDF)合成匹配滤波器,对尺度变化范围为2.5:1的目标区域进行实时识别与定位,并根据相关识别结果计算了定位精度.仿真实验结果表明,光学相关的识别率高,定位误差远小于传统导航模式的定位误差,可应用于飞行器精确定点着陆中.     

一种求解背包问题的自适应算法

针对二表算法和动态二表算法求解背包问题,提出一个并行自适应算法,能用 个处理机、 的时间、 的空间求解背包问题 ,根据处理机的数目以及存储器的容量来选择参数,充分利用已有的硬件资源,以求得最快的求解速度。实验结果证明了该算法的有效性。     

Health vs. privacy? The risk-risk tradeoff in using COVID-19 contact-tracing apps

In the midst of the COVID-19 pandemic, contact-tracing apps have emerged as reliable tools for public health communication and the promotion of preventative health. However, to function properly, contact-tracing apps require users to provide sensitive information, which has raised concerns about data disclosure, misuse and social surveillance. Little is known about how different types of risk perception simultaneously hinder and motivate individuals' engagement in mobile health apps, particularly in the context of a pandemic. Based on the privacy calculus theory and the risk-risk tradeoff concept, this study examined the risk-risk tradeoff model to enhance the understanding of COVID-19 contact-tracing app users’ decision from the perspective of risk minimization. Findings from PLS-SEM and fsQCA revealed that users engage in health risk-privacy risk tradeoff when evaluating and deciding to use the apps. The focal study therefore contributes to the research on privacy calculus theory and calls for a balanced managerial solution to mitigate this tradeoff dilemma.