三级对称叛徒追踪新方案

提出了一种新的对称叛徒追踪方案。基于加密广播技术和Hash函数理论,构造了密钥方案、加密方案、解密方案和叛徒追踪算法,利用Chernoff界确定了系统参数值。新方案可以有效对抗加密广播业务中的共谋密钥攻击。相对于已有的CFN对称方案,新方案具有更低的个人密钥存储复杂度、用户计算复杂度和更少的数据冗余。     

一种适合大型动态多播的密钥管理方案

分析了已有基于两层结构的密钥管理方案的优缺点，在此基础上综合了上述方案和PE方案的特点，提出了一个新的密钥管理方案，并给出了相应的更新算法。通过对本方案和其他方案的密钥存储量、加密计算量、网络通信量等性能的分析结果表明，该方案在组控制器和子组控制器方面都具有良好的通信效率、较低的计算开销和可扩展性，适用于大型的动态多播环境。     

一个新的理想的多秘密共享方案

Hsu、Cheng、Tang和Zeng基于单调张成方案设计了一个理想的多秘密共享方案（HCTZ方案）,但该方案不具有可验证性。基于单调张成方案和双变量单向函数,提出了一个新的理想的多秘密共享方案。新方案通过增加每个密钥的维数,在保留HCTZ方案原有性质的同时实现了可验证性。该方案的安全性得到证明,且具有较强的实用价值。     

一个新的代理盲签名方案

通过引入消息拥有者的私钥和公钥对Schnorr型盲签名方案进行了改进，构造了一个新的盲签名方案，基于新的盲签名方案构造了一个代理盲签名方案。分析表明新方案不仅同时拥有代理签名和盲签名的特点，具有不可伪造性、可区分性、不可抵赖性、可注销性等性质，而且和Tan等人的方案以及Lal等人的方案相比减少了求幂运算的次数，避免了求逆运算，使签名速度有了较大提高。     

基于光子技术的微波频率测量研究进展

微波频率测量及分析在军用、民用领域中有着重要战略地位和重大需求,并随着通信、雷达、电子对抗中工作频率的不断攀升而面临着前所未有的挑战。近年来以微波光子学为基础的光子型微波频率测量技术应运而生,因其在瞬时带宽、抗电磁干扰方面有着显著优势,得到了长足发展,并具有重要的理论意义和实用价值。针对目前主要研究的光子型微波频率测量方案,如微波光子扫频方案、频率 幅度映射方案、频率 空间映射方案、频率 时间映射方案、光子压缩感知方案、以及数字化测频方案等,介绍了其基本原理及实验方案,并对各种方案的研究现状与进展进行了梳理、分析和总结。最后,对光子型微波频率测量的趋势和前景进行了简要探讨和展望。     

构建安全可靠的大亚湾核电站管理计算机网络

本文主要阐述了大亚湾核电站网络改造实施的过程和技术方案的特点，并着重介绍了方案在系统可靠性方面的考虑。主要从背景、需求、技术选型、方案技术特点和测试方案几个方面来进行描述。     

基于FOO投票协议的无收据电子投票方案

安全且实用的电子投票协议是信息安全领域的热点问题之一。引入了盲签名、投票编号、申诉标识等工具,提出了一种新的无收据的电子投票方案,该方案进一步完善了FOO投票协议,可保证选票的匿名性、可验证性和无收据性,并且允许投票者中途弃权。该方案不仅保持了原方案的各种优点,而且增强了系统的安全性和灵活性。因此,与其他类似方案相比较,该方案具有更好的通用性和实用性。     

压制式毫米波干扰模拟器设计

压制式毫米波干扰模拟器能够真实模拟引信所面临的干扰环境,为实验提供阻塞噪声、瞄准噪声、扫频噪声。本文分析了压制式噪声产生原理,阻塞噪声、瞄准噪声采用噪声调频的方式得到,扫频噪声采用函数扫频的方式得到。提出了三种可行的毫米波干扰模拟器的实现方案:上变频方案、滤波方案和倍频方案。对以上三种方案进行了分析和比较,最终设计采用了倍频方案,并给出了实验结果。     

一个叛逆者追踪方案分析和改进

最近,王青龙等人提出了一种新的基于双线性映射的公钥叛逆者追踪方案,并称该方案具有完全抗共谋性、完全撤销性、完全恢复性和黑盒追踪性等优点.分析了王青龙等人的方案,指出该方案不能实现完全撤销功能,并对王青龙等人的方案进行了改进,提出了一个新的基于双线性映射的叛逆者追踪方案.为了减少存储、计算和通信开销,提出的方案使用多项式和过滤函数构建追踪方案.当发现叛逆者时,提出的方案能够在不更新合法用户密钥的前提下,同时安全撤销多个叛逆者,实现了完全撤销,克服了王青龙等人方案的缺陷.方案的安全性基于离散对数问题和判定Diffie-Hellma问题为困难问题.安全性证明和性能分析表明提出的方案是安全的,能满足完全抗共谋性、完全可恢复性、黑盒追踪性和完会撤销性.同时,就存储、计算和通信开销而言,提出的方案比王青龙等人的方案低.     

面向多服务的可灵活撤销的非对称公钥叛逆者追踪方案

Matsushita等人提出了一个可灵活撤销用户的公钥叛逆者追踪方案，但其方案是对称方案，并且没有提供多服务的功能。利用不经意多项式估值协议(OPE)和服务参数提出了一个改进的Matsushita方案。改进方案在保持了原Matsushita方案可灵活撤销用户、黑盒子追踪、安全性不变的基础上，增加了提供多种服务、防止叛逆者抵赖（非对称）等优点，整体性能好于Matsushita方案。     

Integrated control design for driver assistance systems based on LPV methods

The paper proposes a control design method for a driver assistance system. In the operation of the system, a predefined trajectory required by the driver with a steering command is followed. During manoeuvres the control system generates differential brake moment and the auxiliary front-wheel steering angle and changes the camber angles of the wheels in order to improve the tracking of the road trajectory. The performance specifications are guaranteed by the local controllers, i.e. the brake, the steering, and the suspension systems, while the coordination of these components is provided by the supervisor. The advantage of this architecture is that local controllers are designed independently, which is ensured by the fact that the monitoring signals are taken into consideration in the formalisation of their performance specifications. The fault-tolerant control can be achieved by incorporating the detected fault signals in their performance specifications. The control system also uses a driver model, with which the reference signal can be generated. In the control design, the parameter-dependent linear parameter-varyingmethod, which meets the performance specifications, is used. The operation of the control system is illustrated through different normal and emergency vehicle manoeuvres with a high-accuracy simulation software.     

Nonblocking supervisory control of nondeterministic systems viaprioritized synchronization

Shayman and Kumar (1995) showed that supervisory control of nondeterministic discrete-event systems, in the presence of driven events, can be achieved using prioritized synchronous composition as a mechanism of control, and trajectory models as a modeling formalism, first introduced by Heymann (1990). The specifications considered in this earlier work were given by prefix-closed languages. In this paper, we extend this work to include markings so that nonclosed specifications and issues such as blocking can be addressed. It is shown that the usual notion of nonblocking, called language model nonblocking, may not be adequate in the setting of nondeterministic systems, and a stronger notion, called trajectory model nonblocking, is introduced. Necessary and sufficient conditions for the existence of language model nonblocking as well as trajectory model nonblocking supervisors are obtained for nondeterministic systems in the presence of driven events in terms of extended controllability and relative-closure conditions and a new condition called the trajectory-closure condition     

度量区间时序逻辑下四旋翼的集成任务与运动规划

本文采用优化方法解决度量区间时序逻辑下进行四旋翼的集成任务与运动规划问题。传统方法通常将任务约束和运动约束分层处理。由于不同规划层所使用的抽象模型并不完全匹配,任务规划层求解出的高层策略往往无法有效地被低层的运动规划层执行,从而只能找到次优的运动轨迹甚至找不到解。本文摒弃分层规划的策略,采用B样条拟合运动轨迹,将问题转化问一个混合整数线性规划问题,直接在同一层处理带有时序逻辑的任务约束以及运动约束。与其他现有方法对比,我们的方法保证了连续时间下的轨迹也可以完全满足所有约束条件,而非只有离散的轨迹点才可以满足。我们用四旋翼模型进行了一系列仿真验证,仿真结果表明了方法的有效性     

Temporal logic motion planning for dynamic robots

In this paper, we address the temporal logic motion planning problem for mobile robots that are modeled by second order dynamics. Temporal logic specifications can capture the usual control specifications such as reachability and invariance as well as more complex specifications like sequencing and obstacle avoidance. Our approach consists of three basic steps. First, we design a control law that enables the dynamic model to track a simpler kinematic model with a globally bounded error. Second, we built a robust temporal logic specification that takes into account the tracking errors of the first step. Finally, we solve the new robust temporal logic path planning problem for the kinematic model using automata theory and simple local vector fields. The resulting continuous time trajectory is provably guaranteed to satisfy the initial user specification.     

Estimation and model predictive control of non-linear batch processes using linear parameter varying models

In this paper, feedback control is implemented for batch processes using linear models which describe the batch dynamics locally along its optimal trajectory. A Linear Parameter Varying (LPV) model obtained by interpolation between these multiple models is used to emulate the behaviour of the non-linear batch. The interpolation functions and state estimates are computed using a recursive Bayesian technique. The control technique is based on model predictive control (MPC) which is used for regulation and targeting the product specifications at the end of the batch.     

Adaptive control for autonomous ships with uncertain model and unknown propeller dynamics

Motion control is one of the most critical aspects in the design of autonomous ships. During maneuvering, the dynamics of propellers as well as the craft hydrodynamical specifications experience severe uncertainties. In this paper, an adaptive control approach is proposed to control the motion and trajectory tracking of an autonomous vessel by adopting neural networks that is used for estimating the dynamics of the propellers and handling hydrodynamical uncertainties. Considering that the maneuvering model of a vessel resemble a nonlinear non-affine-in-control system, the proposed neural-based adaptive control algorithm is designed to estimate the nonlinear influence of the input function which in this case is the dynamics of propellers and thrusters. It is also shown that the proposed methodology is capable of handling state dependent uncertainties within the ship maneuvering model. A Lyapunov-based technique and Uniform Ultimate Boundedness are used to prove the correctness of the algorithm. To assess the method’s performance, several experiments are considered including trajectory tracking simulations in the port of Rotterdam.     

空间相贯曲线轨迹控制与仿真

针对空间相贯曲线轨迹控制的复杂性和特殊性, 研究一种新型空间相贯曲线插补算法. 通过建立相贯曲线的数学模型, 提出了由直线轴和旋转轴组成的非笛卡尔坐标中的相贯曲线轨迹直接插补和速度控制算法, 并对算法进行仿真. 仿真结果表明, 所提出的相贯曲线轨迹插补算法具有较高的轨迹控制精度和速度稳定性, 具有良好的应用前景.     

基于三步法的机械臂轨迹跟踪控制

考虑机械臂末端轨迹跟踪控制问题,以跟踪逆运动学求解出的末端期望轨迹对应的各关节期望角度为控制目标.设计了一种基于三步法的控制器,该控制器由类稳态控制、可变参考前馈控制和误差反馈控制3部分组成.证明了该控制器可以通过控制机械臂的各关节力矩实现各关节实际角度对期望角度的状态跟踪,进而使得末端轨迹渐近跟踪期望轨迹,并且跟踪误差是输入到状态稳定的.仿真表明基于三步法控制器的空间机械臂末端可以渐近跟踪期望轨迹,并且该算法可以克服系统的末端负载质量变化等不确定性的影响.